Green Solvents in Organic Synthesis E-Book
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- Herausgeber: Wiley-VCH GmbH
- Kategorie: Wissenschaft und neue Technologien
- Sprache: Englisch
- Veröffentlichungsjahr: 2024
A well-timed book that aims at sustainability in synthesis and production of chemicals. Details the different green solvents, their physiochemical properties, performance, and distinct applications. Presents a greener approach to replacing the conventional solvents by sustainable solvents by finding similarities in their reaction mechanisms. It also includes the technical, economic, and environmental aspects of these solvents showing how to maximize their reuse and recycling.
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Table of Contents
Cover
Table of Contents
Title Page
Copyright
1 Recent Achievements in Organic Reactions in Alcohols
1.1 Introduction
1.2 Alcohols as Green Solvents
1.3 Alcohols as Green Solvents and Catalysts
1.4 Alcohols as Green Solvents and Hydrogen Donors
1.5 Miscellaneous
1.6 Summary and Concluding Remarks
Acknowledgments
References
2 Recent Achievements in Organic Reactions in MeCN
2.1 Introduction
2.2 MeCN in Transition Metal-catalyzed Reactions Without Radicals Involved
2.3 MeCN in Transition Metal-free Catalyzed Reactions Without Radicals Involved
2.4 MeCN in C—X Bonds Formation With Radicals Involved
2.5 Conclusion
References
3 Recent Achievements in Organic Reactions in Bio-based Solvents
3.1 Introduction
3.2 Glycerol
3.3 Polyethylene Glycols (PEGs)
3.4 2-Methyltetrahydrofuran (2-MeTHF)
3.5 Cyclopentyl Methyl Ether (CPME)
3.6 Organic Carbonates
3.7 γ-Valerolactone (GVL)
3.8 Ethyl Lactate (EL)
3.9 Miscellaneous
3.10 Conclusions and Outlook
References
4 Recent Achievements in Organic Reactions in DMSO
4.1 Pummerer-type Activation of DMSO
4.2 Selectfluor-enabled Activation of DMSO
4.3 Activation of DMSO Enabled by Single-electron Transformation
4.4 Electrocatalytic Synthesis Enabled Activation of DMSO
4.5 Photocatalytic Reaction Enabled Activation of DMSO
4.6 DMSO Acts as the Metal Ligand
4.7 Some Special Activation or Usage of DMSO
4.8 Summary and Outlook
References
5 The Use of DMC as Green Solvent in Organic Synthesis
5.1 Introduction
5.2 Organic Reactions in DMC
References
6 Applications of Green Deep Eutectic Solvents (DESs) in Synthetic Transformations
6.1 Introduction
6.2 Cross-coupling Reactions in Deep Eutectic Solvents
6.3 Oxidation Reactions in Deep Eutectic Solvents
6.4 Reduction Reactions in Deep Eutectic Solvents
6.5 Cyclization Reactions in Deep Eutectic Solvents
6.6 Condensation Reactions in Deep Eutectic Solvents
6.7 Multicomponent Reactions in Deep Eutectic Solvents
6.8 Other Organic Reactions in Deep Eutectic Solvents
6.9 Polymerization in DSEs
6.10 Conclusion
References
7 Recent Achievements in Organic Reactions in Ionic Liquids
7.1 Introduction
7.2 Transition Metal-catalyzed Reactions
7.3 Outlook
References
8 Recent Achievements in Organic Reactions in Ketones and Esters
8.1 Introduction
8.2 Organic Reactions in Ketones
8.3 Organic Reactions in Esters
8.4 Conclusion
References
9 Recent Achievements in Organic Reactions in Polyethylene Glycol
9.1 Introduction
9.2 PEG in Pd-catalyzed Coupling Reactions
9.3 PEG in Cu-catalyzed Reactions
9.4 PEG in Ni, Ru, and Pt-catalyzed Reactions
9.5 PEG in Organocatalysis Reactions
9.6 PEG in Multicomponent Reactions
9.7 PEG in Cyclization Reactions
9.8 Conclusion
Acknowledgments
References
10 Recent Advances in Organic Reactions Using Water as Solvent
10.1 Introduction
10.2 Cross-Coupling Reactions
10.3 C–H Functionalization
10.4 C–C Activation
10.5 C–O Cleavage Reactions
10.6 Oxidative and Reductive Reactions
10.7 Substitution Reactions
10.8 Addition Reactions
10.9 Cyclization or Annulation Reactions
10.10 Multicomponent Reaction (MCR)
10.11 Domino/Tandem/Cascade Reactions
10.12 Rearrangement or Insertion Reactions
10.13 Amide Condensation Reactions
10.14 Summary and Conclusions
Acknowledgments
References
Note
Index
End User License Agreement
List of Tables
Chapter 1
Table 1.1 Physical and chemical properties of alcohols [3].
Table 1.2 Guidelines for solvents for common alcohols.
Chapter 3
Table 3.1 Zincate-promoted remote functionalization in 2-MeTHF.
Table 3.2 Peroxodisulfate-assisted benzylation of coumarin with styrene and ...
List of Illustrations
Chapter 1
Scheme 1.1 Structure of alcohols.
Scheme 1.2 Ruthenium-catalyzed asymmetric hydrogenation of chromanone.
Scheme 1.3 Asymmetric hydrogenation of quinoline derivatives catalyzed by a ...
Scheme 1.4
N
-arylhydroxylamine synthesis via transfer hydrogenation reaction...
Scheme 1.5 Proposed mechanism for semi-hydrogenation of nitroarenes-catalyze...
Scheme 1.6 Glycerol as a green solvent in the oxidation of thiols to disulfi...
Scheme 1.7 Selective oxidation of sulfides to sulfoxides in PEG-1000.
Scheme 1.8 Model reaction for aromatic alcohol oxidation to ketone using TiO
Scheme 1.9 Aerobic oxidative iodination of electron-rich aromatics in ethyle...
Scheme 1.10 An efficient system for the synthesis of 2-organylselanyl pyridi...
Scheme 1.11 Room-temperature intramolecular
exo
-hydroamination of
N
-alkenyl ...
Scheme 1.12 Synthesis of azides from chlorinated heteroaromatic compounds in...
Scheme 1.13 Application of PEG-400 in asymmetric organocatalytic Michael add...
Scheme 1.14 Synthesis of aromatic ketones by chemically selective addition o...
Scheme 1.15 Application of polypyrrole/Cu(II) in the synthesis of 4-aryl-NH-...
Scheme 1.16 Base-free Cu(I)-catalyzed 1, 3-dipolar cycloaddition of azides w...
Scheme 1.17 Palladium-catalyzed cycloisomerization of (
Z
)-enynols into furan...
Scheme 1.18 K
2
CO
3
-mediated cyclization and rearrangement to form pyridols.
Scheme 1.19 Application of ethylene glycol in visible-light-promoted aerobic...
Scheme 1.20 Sc(OTf)
3
-catalyzed [4 + 2] annulation reaction of α-hydroxyaceto...
Scheme 1.21 Synthesis of 1-sulfanyl- and 1-selanylindolizines.
Scheme 1.22 Synthesis of octahydroacridine catalyzed by TiCl
3
from substitut...
Scheme 1.23 One-pot synthesis of 2-propylquinolines from anilines through th...
Scheme 1.24 Hiyama-type reaction in neoteric biomass-derived solvents involv...
Scheme 1.25 Symmetrical and unsymmetrical
β
,
β
-diarylation of acry...
Scheme 1.26 Schematic presentation of Suzuki cross-coupling reaction between...
Scheme 1.27 Phenoxycarbonylation of aryl iodides with phenols in PEG.
Scheme 1.28 Copper-catalyzed cross-coupling reactions of diaryl diselenides ...
Scheme 1.29 C—N and C—S bond formation reactions catalyzed by Cu
2
ONP in glyc...
Scheme 1.30 PEG-mediated recyclable borylative coupling of vinyl boronates w...
Scheme 1.31 Synthesis of 2-aminothiazoles in PEG-400.
Scheme 1.32 Synthesis of
N
-arylpyrroles from 2,5-dimethoxytetrahydrofuran in...
Scheme 1.33 Ammonium acetate-promoted one-pot tandem aldol condensation/aza-...
Scheme 1.34 Reductive amination of aldehydes and ketones.
Scheme 1.35 Condensation reaction of benzil, benzaldehyde, and ammonium acet...
Scheme 1.36 Benzimidazole derivatives were synthesized by reaction of
o
-phen...
Scheme 1.37 The synthesis of benzimidazole, benzothiazole, benzoxazole, quin...
Scheme 1.38 Three-component reactions of 1,3-cyclohexanediones and formaldeh...
Scheme 1.39 Two-step sequential reactions of arylhydrazines, HCHO,
β
-ke...
Scheme 1.40 Synthesis of 2,5-dihydropyridine derivatives by gold-catalyzed r...
Scheme 1.41 One-pot three-component reaction of 5-amino-2,3-dihydro-7
H
-thiaz...
Scheme 1.42 Michael reactions of amines, anilines, and indoles with
α,β
...
Scheme 1.43 Synthesis of amino acid-based dithiocarbamate by a three-compone...
Scheme 1.44 Glycerol-mediated synthesis of 5-substituted 1
H
-tetrazole.
Scheme 1.45
N
-arylation of indoles with aryl halides using copper/glycerol....
Scheme 1.46 “Vitamin C/glycerol”-promoted copper (II)-catalyzed
N
-arylation ...
Scheme 1.47 Catalyst-free synthesis of di(indolyl)methanes, xanthene-1,8(
2H
)...
Scheme 1.48 One-pot three-component synthesis of 4
H
-pyrans of carbonyl compo...
Scheme 1.49 Catalyst-free synthesis of 2,4,5-triaryl and 1,2,4,5-tetraaryl i...
Scheme 1.50 The Pictet–Spengler reactions of
L
-tryptophan methyl ester and a...
Scheme 1.51 Condensation of trimethyl phosphite with acetaldehyde and anilin...
Scheme 1.52 Catalyst-free methodology for chemoselective
N
-
tert
-butyloxycarb...
Scheme 1.53 Transfer hydrogenations of representative unsaturated organic co...
Scheme 1.54 Iridium-catalyzed asymmetric transfer hydrogenation of alkynyl k...
Scheme 1.55 Bifunctional
N
-doped Co@C catalysts for base-free transfer hydro...
Scheme 1.56 Reductive
N
-alkylation of nitro compounds with an equivalent num...
Scheme 1.57 Ruthenium-catalyzed reduction of allylic alcohols.
Scheme 1.58 Rh-catalyzed hydroaminomethylation reaction in glycerol.
Scheme 1.59 Glycerol as a chemical selective reductant of sulfoxide.
Scheme 1.60 CO
2
capture and activation by superbase/PEG and its subsequent c...
Scheme 1.61 Equimolar CO
2
capture by
N
-substituted amino acid salts and subs...
Scheme 1.62 PEG-enhanced chemoselective synthesis of organic carbamates from...
Scheme 1.63 Synthesis of cyclic carbonate from vicinal halohydrins and CO
2
i...
Scheme 1.64 Organic reactions involving PEG radicals in compressed carbon di...
Scheme 1.65 PEG radical-initiated oxidation of benzylic alcohols in compress...
Scheme 1.66 PEG radical-initiated benzylic C—H bond oxygenation in compresse...
Scheme 1.67 The structural formulae and proposed pathways of organic reactio...
Scheme 1.68 Ring opening of epoxides with amines.
Scheme 1.69 The synergistic action of PFTB and [EMIM]BF
4
promotes the intern...
Chapter 2
Scheme 2.1 Ni-catalyzed coupling of acetonitrile with aldehydes.
Scheme 2.2 Ni-catalyzed cyanomethylation of aldehydes.
Scheme 2.3 Pd/Cu-catalyzed diboration of propargylic alcohols.
Scheme 2.4 Cu-mediated assisted tandem catalyzed double functionalization.
Scheme 2.5 Iron-catalyzed reductive Strecker reaction.
Scheme 2.6 Cu-catalyzed diamination of styrenes.
Scheme 2.7 Palladium-catalyzed synthesis of tetrahydrofuroindoles.
Scheme 2.8 Copper-bisoxazoline-catalyzed allylic oxidation.
Scheme 2.9 Copper(I)-catalyzed asymmetric allylic oxidation.
Scheme 2.10 Oxidation of alkanes and alcohols via Cu catalyst/TBHP system.
Scheme 2.11 Oxidation of toluene.
Scheme 2.12 Oxidative amination of benzylic C—H bonds.
Scheme 2.13 Oxidation of ethylbenzene.
Scheme 2.14 Epoxidation of olefins by hydrogen peroxide.
Scheme 2.15 Synthesis of
α,β
-unsaturated nitriles.
Scheme 2.16 Synthesis of phenol.
Scheme 2.17 Synthesis of benzoic acids.
Scheme 2.18 Synthesis of
Z
-
α,β
-unsaturated esters.
Scheme 2.19 Cascade aminooxygenation reaction.
Scheme 2.20 Oxidation of MPS.
Scheme 2.21 Pd-catalyzed oxidative cross-trimerization.
Scheme 2.22 Pd-catalyzed synthesis of 1,4-dihydropyridines.
Scheme 2.23 Pd-catalyzed oxidative arylalkylation of alkenes.
Scheme 2.24 Palladium-catalyzed deoxygenation reaction.
Scheme 2.25 Rh-catalyzed hydroformylation and hydrogenation.
Scheme 2.26 Reduction of nitroarenes.
Scheme 2.27 Hydrodehalogenation of aryl chlorides and aryl bromides.
Scheme 2.28 Selective N-methylation or N-formylation. Nakazawa and coworkers...
Scheme 2.29 Double hydrosilylation of acetonitrile.
Scheme 2.30 Benzyne 1,2,4-trisubstitution and dearomatization.
Scheme 2.31 Cobalt(II) bromide-catalyzed allylation of alkyl halides.
Scheme 2.32 CuI/PPBO-catalyzed coupling of (hetero)aryl iodides with phenols...
Scheme 2.33 Allylic substitution.
Scheme 2.34 Cu-catalyzed cyanation of indoles with acetonitrile.
Scheme 2.35 Ni-catalyzed cross-electrophile-coupling.
Scheme 2.36 Ni-catalyzed C3-cyanation of
N
-aryl indoles.
Scheme 2.37 Ni-catalyzed cross-coupling for unsymmetrical thioethers.
Scheme 2.38 Rh/Cu-catalyzed asymmetric allylic alkylation of terminal alkyne...
Scheme 2.39 Copper-catalyzed Chan-Lam cross-coupling.
Scheme 2.40 NiCl
2
/2,2′-bipyridine-catalyzed synthesis of diarylsulfides.
Scheme 2.41 Rh-catalyzed cyclization of benzodihydrofurans.
Scheme 2.42 Pd-catalyzed synthesis of pyridines.
Scheme 2.43 PdI
2
-catalyzed carbonylation.
Scheme 2.44 Cu-catalyzed intermolecular cycloaddition.
Scheme 2.45 Pd/C-catalyzed synthesis of trisubstituted nicotinonitriles.
Scheme 2.46 Pd/Cu-catalyzed synthesis of benzofurans.
Scheme 2.47 Co-catalyzed ring-opening [3+2] annulation.
Scheme 2.48 Synthesis of diamino dihydroquinazolines.
Scheme 2.49 Pd-catalyzed [3+2] cycloaddition of amino esters or amino acids....
Scheme 2.50 Cu-catalyzed synthesis of 3-sulfonyl benzofurans and indoles.
Scheme 2.51 [3+2] Cycloaddition process from nonactivated aziridines.
Scheme 2.52 Iodolactonization of alkylidene-cyclopropyl esters.
Scheme 2.53 Electrophilic deamination reaction of
α,β
-unsaturated ...
Scheme 2.54 Lewis acid-catalyzed [3+2] cycloaddition.
Scheme 2.55 Synthesis of benzotriazoles.
Scheme 2.56 Synthesis of 2-aryl terephthalates via [3+3] cyclization.
Scheme 2.57 Synthesis of
N
-acetylbenzoxazine.
Scheme 2.58 Synthesis of 2-substituted indoles.
Scheme 2.59 Synthesis of polycyclic spiroindolines.
Scheme 2.60 Synthesis of 2,2,2-trichloroethanamines and 2,2-dichloroethenami...
Scheme 2.61 Synthesis of
N
-aryl-
γ
-aminonitriles.
Scheme 2.62 Synthesis of benzo[
g
]- and dihydropyrano[2,3-
g
]chromene derivati...
Scheme 2.63 Synthesis of bis(4
H
-chromene)-and 4
H
-benzo[
g
]chromene-3,4-dicarb...
Scheme 2.64 Synthesis of propargylamines.
Scheme 2.65 Monobromination of phenols and anisoles.
Scheme 2.66 Synthesis of
S
-acyl- and
N
-acylcysteines.
Scheme 2.67 Selective esterification of primary alcohols.
Scheme 2.68 Synthesis of
Z
-thiovinyl sulfone.
Scheme 2.69 Synthesis of mono- and difluoroimines.
Scheme 2.70 Synthesis of florfenicol phosphodiester.
Scheme 2.71 Synthesis of
γ
-ketonitriles.
Scheme 2.72 Mechanism of synthesis of
γ
-ketonitriles.
Scheme 2.73 Synthesis of 1-cyanoethylated 3,4-dihydronaphthalenes.
Scheme 2.74 Silicon heterocycle synthesis.
Scheme 2.75 Synthesis of trifluoromethyl tertiary alcohols.
Scheme 2.76 Photo-induced decarboxylation of silacarboxylic acids.
Scheme 2.77 Copper-catalyzed carboamination of alkenes.
Scheme 2.78 Visible light promoted diazenylation of enol silyl ethers.
Scheme 2.79 Synthesis of benzophosphole oxides.
Scheme 2.80 Synthesis of phosphorylated pyrrolines.
Scheme 2.81 Synthesis of 2-aryloxy phenylacetylenes.
Scheme 2.82 Synthesis of cyanomethylated benzoxazines.
Scheme 2.83 Mechanism for synthesis of benzoxazines.
Scheme 2.84 Synthesis of thiophosphates.
Scheme 2.85 Synthesis of imidazopyridines.
Scheme 2.86 Synthesis of tetrasubstituted
β
-sulfonyl enamines.
Scheme 2.87 Synthesis of (
E
)-
β
-sulfonyl enamines.
Scheme 2.88 Radical fluorination of tertiary alkyl halides.
Scheme 2.89 C—H iodination and nitration of indoles.
Scheme 2.90 Iron(II)-catalyzed functionalization of C—H bonds.
Scheme 2.91 TCCA-induced chlorine radical cascade chlorination.
Scheme 2.92 Ring-opening iodination and bromination.
Chapter 3
Scheme 3.1 Catalyst-free synthesis of 1,8-dioxo-decahydroacridines in glycer...
Scheme 3.2 Ring-opening of glycidyl ethers with amines in glycerol.
Scheme 3.3 The reaction of α-hydroxyacetophenone and
N
-methylpyrrole in glyc...
Scheme 3.4 The three-component reaction of α-hydroxyacetophenone,
N
-methylin...
Scheme 3.5 Synthesis of pyrido[2,3-
d
]pyrimidine under microwave heating in g...
Scheme 3.6 Electrochemical cobalt-catalyzed C–H activation in glycerol.
Scheme 3.7 CuNPs-catalyzed reduction of nitrobenzene in glycerol.
Scheme 3.8 One-pot tandem C1-indolylation and
N
-alkylation of tetrahydroisoq...
Scheme 3.9 The three-component reaction of indole, dimedone, and aromatic al...
Scheme 3.10 Palladium-catalyzed cyclocarbonylation in 2-MeTHF.
Scheme 3.11 Palladium-catalyzed allylative dearomatization in 2-MeTHF.
Scheme 3.12 Effect of 2-MeTHF on both the I/Zn exchange step and the butyl 1...
Scheme 3.13 The ring-opening of epoxide in 2-MeTHF.
Scheme 3.14 Chemoselective reduction-monofluoromethylation of diselenides in...
Scheme 3.15 Flow synthesis of 2
H
-azirines from vinyl azides in CPME.
Scheme 3.16 Heterogeneous manganese-catalyzed C–H oxidation under continuous...
Scheme 3.17 Palladium-catalyzed intramolecular C(sp3)–H α-arylation for the ...
Scheme 3.18 Divergent synthesis of 1,3-dicarbonyl compounds in CPME.
Scheme 3.19 Catalyst-free thioamination of 1,4-naphthoquinone in CPME.
Scheme 3.20 Sonogashira reaction in the CPME–water azeotropic mixture.
Scheme 3.21 Metal-free synthesis of pyrrolo[1,2-
a
]quinoline in DEC.
Scheme 3.22 Visible light-induced synthesis of thiocyanated heterocycles in ...
Scheme 3.23 Visible-light-promoted synthesis of aroylated heterocycles in DM...
Scheme 3.24 C3 substitution of 4-hydroxycoumarins with benzyl alcohols in DM...
Scheme 3.25 DMC as both solvent and reactant in organic reactions.
Scheme 3.26 Continuous flow organocatalyzed methoxycarbonylation of benzyl a...
Scheme 3.27 Palladium-catalyzed oxidative aminocarbonylation in PC.
Scheme 3.28 Palladium-catalyzed C–H alkenylation in GVL.
Scheme 3.29 Hiyama cross-coupling between aryl bromide and triethoxyvinylsil...
Scheme 3.30 C2–H arylation of indoles catalyzed by palladium-containing meta...
Scheme 3.31 MW-assisted coupling of heteroaromatics and aryl halides in GVL....
Scheme 3.32 Rhodium-catalyzed synthesis of isoquinolino[1,2-
b
]quinazolines i...
Scheme 3.33 EL-mediated synthesis of azobenzenes.
Scheme 3.34 EL-participating three-component dehydrogenative reaction for th...
Scheme 3.35 Some novel biomass-derived chemicals proposed as potential solve...
Chapter 4
Scheme 4.1
Scheme 4.2
Scheme 4.3
Scheme 4.4
Scheme 4.5
Scheme 4.6
Scheme 4.7
Scheme 4.8
Scheme 4.9
Scheme 4.10
Scheme 4.11
Scheme 4.12
Scheme 4.13
Scheme 4.14
Scheme 4.15
Scheme 4.16
Scheme 4.17
Scheme 4.18
Scheme 4.19
Scheme 4.20
Scheme 4.21
Scheme 4.22
Scheme 4.23
Scheme 4.24
Scheme 4.25
Scheme 4.26
Scheme 4.27
Scheme 4.28
Scheme 4.29
Scheme 4.30
Scheme 4.31
Scheme 4.32
Scheme 4.33
Scheme 4.34
Scheme 4.35
Scheme 4.36
Scheme 4.37
Scheme 4.38
Scheme 4.39
Scheme 4.40
Scheme 4.41
Scheme 4.42
Scheme 4.43
Scheme 4.44
Scheme 4.45
Scheme 4.46
Scheme 4.47
Scheme 4.48
Scheme 4.49
Scheme 4.50
Scheme 4.51
Scheme 4.52
Scheme 4.53
Scheme 4.54
Scheme 4.55
Chapter 5
Scheme 5.1 Biaryl coupling of aryl iodides and organoboron reagents.
Scheme 5.2 Silica-supported FeCl
3
-catalyzed aminal synthesis.
Scheme 5.3 Copper-catalyzed oxidative coupling reaction of carboxylic acids ...
Scheme 5.4 Intramolecular hydroalkoxylation of double bonds.
Scheme 5.5 NaAlO
2
-catalyzed carboxymethylation of DMC.
Scheme 5.6 Palladium-catalyzed carbonylative transformation of benzyl amines...
Scheme 5.7 Preparation of HMF from
D
-fructose in DMC.
Scheme 5.8 Synthesis of sulfonimidates and sulfonimidamides in DMC.
Scheme 5.9 Asymmetric copper-catalyzed Si–H insertion of 1-aryl-2,2,2-triflu...
Scheme 5.10 Iron-catalyzed insertion reaction of α-diazocarbonyls in DMC.
Scheme 5.11 Iron(III)-catalyzed synthesis of α-substituted homoallylamines....
Scheme 5.12 Iron(II) caffeine-derived ionic salt catalyst in the Diels–Alder...
Scheme 5.13 Palladium-catalyzed aminocarbonylation reaction of 5-iodo-1,2,3-...
Scheme 5.14 Iron-catalyzed hydrosilylation of dicarboxylic acids with amines...
Scheme 5.15 Preparation of 1-aryl-2,2-difluoroalkenes via 1,2-desilylative d...
Scheme 5.16 Synthesis of cyclic carbonates from oxiranes with carbon dioxide...
Scheme 5.17 Cyclization between aliphatic and aromatic 1,4-bifunctional comp...
Scheme 5.18 Synthesis of malonate derivatives from saturated fatty acid meth...
Scheme 5.19 Upgrading of levulinic acid with DMC as solvent/reagent.
Scheme 5.20 Upgrading of levulinic acid with DMC as solvent/reagent.
Scheme 5.21 Iron-catalyzed methylation of secondary amines and imines.
Scheme 5.22 Base-catalyzed cleavage of lignin β-
O
-4 model compounds in DMC....
Scheme 5.23 Palladium-catalyzed coupling of benzyl/allyl alcohols with malon...
Scheme 5.24 Synthesis of
N
-alkyloxaziridines with alkylamines and aldehydes....
Scheme 5.25 Palladium-catalyzed carbonylation of f benzyl alcohols for the s...
Scheme 5.26 NZSM-5 Zeolite catalyzed synthesis of non-symmetrical alkyl carb...
Scheme 5.27 MnCO
3
-300 catalyzed transesterification of alcohols.
Scheme 5.28 Borrowing carbonate-enabled allylic amination reactions in DMC....
Chapter 6
Scheme 6.1 The case of choline chloride + urea DES.
Scheme 6.2 Deep eutectic solvents (DESs) classification.
Scheme 6.3 Representative structures of HBAs and HBDs used for DESs synthesi...
Scheme 6.4 Suzuki–Miyaura reactions performed in melt.
Scheme 6.5 Suzuki–Miyaura reactions performed in melt.
Scheme 6.6 Ligand-based Suzuki–Miyaura coupling with PhB(OH)
2
in DES.
Scheme 6.7 DES-compatible bipyridine palladium for Suzuki–Miyaura reaction....
Scheme 6.8 Suzuki–Miyaura coupling for the synthesis of N-heterocyclics in D...
Scheme 6.9 Suzuki–Miyaura couplings of aryltrifluoroborates in DES.
Scheme 6.10 GO/Fe
3
O
4
@G2/Co for Suzuki coupling reaction in DES.
Scheme 6.11 Mizoroki–Heck reaction performed in melt.
Scheme 6.12 Mizoroki–Heck reaction in DES in the presence of ligand or Pd co...
Scheme 6.13 Mizoroki–Heck reaction in DES in the presence of a Pd–MOF comple...
Scheme 6.14 Mizoroki–Heck coupling in DES for the synthesis of 2-(hetero)ary...
Scheme 6.15 Pd-catalyzed Sonogashira reaction in melt.
Scheme 6.16 Sonogashira reaction in Ph
3
PMeBr/gly.
Scheme 6.17 Sonogashira reaction in AcChCl/urea.
Scheme 6.18 Pd/C-catalyzed ligand-free Sonogashira reaction in DES.
Scheme 6.19 A magnetic Pd-nanocomposite mediated Sonogashira reaction in DES...
Scheme 6.20 A robust NCN–Pd–pincer catalyst for Hiyama reaction in DES.
Scheme 6.21 DES-compatible bipyridine palladium for Hiyama reaction.
Scheme 6.22 Negishi cross-coupling reactions performed in melt.
Scheme 6.23 Stille cross-coupling reaction in DES based on sugar/urea/salt....
Scheme 6.24 Thiophene−aryl coupling
via
direct arylation in DES.
Scheme 6.25 Csp3—H functionalization of ketones with alcohols in DES.
Scheme 6.26 Direct C5 arylation of imidazole derivatives in DES.
Scheme 6.27 Csp3—H arylation and alkynylation of 8-aminoquinoline amides in ...
Scheme 6.28 N-arylation of amines mediated by Cu nanocomposite in DES.
Scheme 6.29 Synthesis of amides
via
aminocarbonylation of (hetero)aryl iodid...
Scheme 6.30 Ullmann amine synthesis in DES.
Scheme 6.31 C—N coupling of aryl iodides with primary/secondary amides in DE...
Scheme 6.32 DES promoted coupling of activated aryl halides with substituted...
Scheme 6.33 Ligand-free Cu(I) or Cu(II)-catalyzed C—O coupling reactions in ...
Scheme 6.34 Fe
3
O
4
@SiO
2
-BT-Cu-catalyzed O-arylation of phenols in DES.
Scheme 6.35 C—S bond formation carried out in DES.
Scheme 6.36 DES mediated C—S coupling of halides with thiols.
Scheme 6.37 Toluene oxidation by hydrogen peroxide in DES.
Scheme 6.38 Cross-dehydrogenation coupling of tetrahydroisoquinoline in DES....
Scheme 6.39 The [3 + 3] tandem annulation–oxidation approach for the synthes...
Scheme 6.40 IBX promoted primary amine oxidative coupling in DES.
Scheme 6.41 The oxidation of benzaldehyde by hydrogen peroxide in DES.
Scheme 6.42 The oxidation of furfural to fumaric acid and maleic acid in DES...
Scheme 6.43 One-pot (two steps) synthesis of 2,5-diarylpyrazines in DES.
Scheme 6.44 Synthesis of α- and β-hydroxyphosphine oxides in a one-pot two-s...
Scheme 6.45 The biomimetic aerobic oxidative desulfurization process in DES....
Scheme 6.46 Rh(I)-catalyzed hydrogenation of methyl
α
-cinnamide in DES....
Scheme 6.47 Reduction of carbonyl compounds and epoxides in DES.
Scheme 6.48 Reductive desulfurization process in DES.
Scheme 6.49 HLADH-catalyzed cinnamaldehyde reduction in DES.
Scheme 6.50 Reduction reaction of nitrobenzene in DES.
Scheme 6.51 The reduction of HAP to (
R
)-PED by K. gibsonii SC0312 in DES.
Scheme 6.52 Paal–Knorr reaction in DES.
Scheme 6.53 Fischer indole synthesis and click reaction in DES.
Scheme 6.54 Synthesis of oxadiazole derivatives in DES.
Scheme 6.55 Diels−Alder Reaction in DES.
Scheme 6.56 Pictet–Spengler dehydrogenative cyclization in DES.
Scheme 6.57 Choline-based DES-mediated Friedlander annulation.
Scheme 6.58 One-pot cyclocondensation for the synthesis of coumarin styryl d...
Scheme 6.59 Knoevenagel condensation in DES.
Scheme 6.60 Synthesis of a library of bis-enol derivatives in DES.
Scheme 6.61 Synthesis of rhodanine derivatives
via
Knoevenagel condensation ...
Scheme 6.62 Self-condensation of
D
-glucosamine to DOF and FZ in DES.
Scheme 6.63 Synthesis of 2-aminoimidazoles
via
condensation in DES.
Scheme 6.64 Distinct stereoselective Michael addition reaction in DES.
Scheme 6.65
L
-proline-catalyzed Knoevenagel condensation in DES.
Scheme 6.66 Acid- and metal-free synthesis of annulated pyrroles in DES.
Scheme 6.67 Synthesis of quinoline derivatives in DES.
Scheme 6.68 Synthesis of sulfonamides in DES.
Scheme 6.69 One-pot synthesis of
α
-amino nitrile derivatives in DES.
Scheme 6.70 Three-component domino reaction in DES.
Scheme 6.71 Three-component synthesis of 1-amidoalkyl naphthols and polyhydr...
Scheme 6.72 Three-component synthesis of 5-alkylidene-thiazolones in DES.
Scheme 6.73 Three-component synthesis of 5-substituted 1
H
-tetrazoles in DES....
Scheme 6.74 Four-component synthesis of functionalized pyrroles in DES.
Scheme 6.75 Multicomponent domino reactions in DES.
Scheme 6.76 Ru-catalyzed isomerization of allylic alcohols into saturated ca...
Scheme 6.77 Cycloisomerization of
γ
-alkynoic acids into cyclic enol-lac...
Scheme 6.78 DES-shifted the equilibrium to the left stabilizing the
trans
-is...
Scheme 6.79 Ring-opening of epoxides with different nucleophiles in DES.
Scheme 6.80 Ring-opening of
o
-tolyl tetrahydrofuran derivatives in DES.
Scheme 6.81 The esterification of acetic acid and alcohol in DES.
Scheme 6.82 Esterification of carboxylic acids in DES without any other addi...
Scheme 6.83 Organolithium promoted anionic polymerization of alkenes in DES....
Scheme 6.84 Glycolysis and polyesterification reactions in DES.
Scheme 6.85 FeCl
3
-catalyzed oxidative polymerization in DES.
Scheme 6.86 RAFT polymerization driven by visible light in DES.
Chapter 7
Figure 7.1 Some commonly used cations and anions for ionic liquids.
Scheme 7.1 Palladium-catalyzed cascade annulation/arylthiolation reaction.
Scheme 7.2 Plausible mechanism for palladium-catalyzed cascade annulation/ar...
Scheme 7.3 Palladium-catalyzed three-component cascade cyclization/alkynylat...
Scheme 7.4 General mechanism for three-component cascade cyclization/alkynyl...
Scheme 7.5 Palladium-catalyzed three-component cascade
S
-transfer reaction....
Scheme 7.6 Plausible mechanism for palladium-catalyzed 4-sulfenylisoxazoles ...
Scheme 7.7 NHC-Pd catalyzed cascade annulation/allylation of acetylenic oxim...
Scheme 7.8 Cascade annulation/alkylation of acetylenic oximes with long-chai...
Scheme 7.9 Palladium-catalyzed cascade cyclization/alkylation of oxime ether...
Scheme 7.10 Palladium-catalyzed ionic liquids-accelerated oxyarylation.
Scheme 7.11 Proposed mechanism for ionic liquids-accelerated oxyarylation.
Scheme 7.12 Palladium-catalyzed cascade of alkynoic acids with unactivated a...
Scheme 7.13 Palladium-catalyzed cascade carboxylative to construct γ-lactone...
Scheme 7.14 The plausible pathway for cascade carboxylative.
Scheme 7.15 Palladium-catalyzed oxidative carbonylation of propargylic amine...
Scheme 7.16 Oxidative carbonylation of aniline to diphenylurea in [Bmim]Br....
Scheme 7.17 Palladium-catalyzed cascade annulation/aminocarbonylation reacti...
Scheme 7.18 Proposed mechanism for cascade annulation/aminocarbonylation rea...
Scheme 7.19 Palladium-catalyzed Sonogashira reaction in two carboxylate-base...
Scheme 7.20 Palladium-catalyzed Sonogashira coupling reaction in [Bmim]PF
6
....
Scheme 7.21 Palladium-catalyzed Sonogashira coupling in
γ
-valerolactone...
Scheme 7.22 Palladium-catalyzed Suzuki reaction in biphasic system.
Scheme 7.23 Pd–NPs@Chitosan-catalyzed Suzuki coupling reaction.
Scheme 7.24 Palladium nanoparticles catalyzed Suzuki coupling reaction.
Scheme 7.25 Pd complex
55
catalyzed Suzuki coupling reaction.
Scheme 7.26 Copper-catalyzed Ullmann-type coupling in Ils.
Scheme 7.27 Copper-catalyzed
N
-arylation of amines in Ils.
Chapter 8
Scheme 8.1 The solvents of Cyrene and NBP.
Scheme 8.2 Production of Cyrene from cellulose.
Scheme 8.3 Sonogashira reaction using Cyrene as the solvent.
Scheme 8.4 Suzuki–Miyaura reaction using Cyrene as the solvent.
Scheme 8.5 Synthesis of urea in Cyrene.
Scheme 8.6 Difluoromethylation of terminal alkynes in Cyrene.
Scheme 8.7 Synthesis of amide in Cyrene.
Scheme 8.8 Menschutkin reaction using Cyrene as a solvent.
Scheme 8.9 (a) Heck reaction and (b) Suzuki reaction in NBP.
Scheme 8.10 Biginelli reaction using NBP as the solvent.
Scheme 8.11 Maitland-Japp reaction using NBP as the solvent.
Scheme 8.12 Linear carbonates and cyclic carbonates.
Scheme 8.13 Pd-catalyzed asymmetric allylic alkylation in different solvents...
Scheme 8.14 Rh-catalyzed asymmetric hydrogenation in different solvents.
Scheme 8.15 PC as a solvent in Rh-catalyzed alkyne hydroacylation reactions....
Scheme 8.16 Organic carbonates as a solvent in Heck reaction.
Scheme 8.17 Visible-light-promoted C—P bond formation in DEC.
Scheme 8.18 Visible-light-promoted cascade cyclization reactions in DMC.
Scheme 8.19 Acid-catalyzed biomass conversions in GVL.
Scheme 8.20 Pd-Catalyzed cross-coupling reactions in GVL.
Scheme 8.21 Pd-Catalyzed C—H arylation of thiophenes with aryl halide in GVL...
Scheme 8.22 Heterogeneous palladium-catalyzed Catellani reaction in GVL.
Scheme 8.23 (a) Suzuki reaction and (b) Glaser reactions in EL.
Scheme 8.24 Synthesis of aryl aldimines in EL or EL/H
2
O system.
Scheme 8.25 Synthesis of 3,4-dihydropyrimidinothiones in EL.
Scheme 8.26 Synthesis of two-substituted benzothiazoles in EL.
Chapter 9
Scheme 9.1 Different organic reactions performed in PEG solvents.
Scheme 9.2 Palladium-catalyzed Heck cross-coupling of aromatic bromides in P...
Scheme 9.3 Intramolecular and intermolecular Heck cross-coupling of aromatic...
Scheme 9.4 Terminal β-arylation of alkyl vinyl ethers and arylation of 1,2,3...
Scheme 9.5 Pd-catalyzed homo- and cross-coupling of aryl halides to synthesi...
Scheme 9.6 NHC–Pd-catalyzed homocoupling in PEG-200.
Scheme 9.7 Microwave-assisted Suzuki–Miyaura coupling in PEG-400.
Scheme 9.8 Suzuki–Miyaura coupling of aromatic halides, carboxylic anhydride...
Scheme 9.9 Pd-catalyzed Suzuki–Miyaura coupling of aromatic chlorides in PEG...
Scheme 9.10 Suzuki–Miyaura coupling of aromatic halides in PEG-400.
Scheme 9.11 Sonogashira reactions in PEG-400.
Scheme 9.12 Carbonylative Sonogashira reactions in PEG-2000.
Scheme 9.13 Cross-coupling of tetraphenylstannane and aromatic halides in PE...
Scheme 9.14 Hiyama cross-coupling in PEG.
Scheme 9.15 Pd-catalyzed hydroalkylation cyclization of alkenyl β-keto ester...
Scheme 9.16 Synthesis of aryl-substituted pyrrole in PEG-200.
Scheme 9.17 Pd-catalyzed C–P bond formation in PEG-600.
Scheme 9.18 Pd-catalyzed oxidation of alkenes and alkynes in PEG.
Scheme 9.19 Pd-catalyzed C—B bond formation in PEG-600.
Scheme 9.20 Cu-catalyzed Suzuki–Miyaura cross-coupling in PEG-400.
Scheme 9.21 Cu-catalyzed Sonogashira couplings in PEG.
Scheme 9.22 Cu-catalyzed C—N bond formation in PEG-400.
Scheme 9.23 Cu-catalyzed
N
-arylation in PEG.
Scheme 9.24 Cu-catalyzed C-N bonds formation in PEG-400.
Scheme 9.25 CuI-catalyzed Click reaction of azides and alkynes in PEG.
Scheme 9.26 CuI-catalyzed thioetherification of aryl halides with alky bromi...
Scheme 9.27 Cu-catalyzed ring-opening arylation of benzazoles with aryl iodi...
Scheme 9.28 Cu-catalyzed C–Se bonds formation in PEG.
Scheme 9.29 Ni-catalyzed reduction and cross-coupling in PEG.
Scheme 9.30 Ru-catalyzed C—H bond activation in PEG-400.
Scheme 9.31 Ru-catalyzed C–H activation/cyclization in PEG-400.
Scheme 9.32 Ru-catalyzed asymmetric hydrogenation of ketones in PEG-400.
Scheme 9.33 Pt-catalyzed reduction and cyclization in PEG.
Scheme 9.34 NHC-catalyzed homocoupling of α-diketones in PEG-400.
Scheme 9.35 Asymmetric organocatalytic Aldol condensation and Michael additi...
Scheme 9.36 Synthesis of 3,4-dihydropyrimidinones in PEG-400.
Scheme 9.37 Multicomponent reactions of hydroxycoumarin in PEG.
Scheme 9.38 CAN-catalyzed Mannich reaction in PEG-400.
Scheme 9.39 Multicomponent reactions 1
H
-benzo[
d
]imidazol-2-amine in PEG-400....
Scheme 9.40 Synthesis of thiazoles in PEG-400.
Scheme 9.41 Synthesis of benzothiazoles and benzimidazoles in PEG.
Scheme 9.42 CAN-catalyzed oxidative cyclization in PEG-300.
Scheme 9.43 Synthesis of six and seven-membered heterocycles in PEG-400.
Chapter 10
Scheme 10.1 Micellar-enhanced ppm Pd-catalyzed Suzuki coupling using EvanPho...
Scheme 10.2 Micellar-enhanced ppm Pd-catalyzed Suzuki coupling using HandaPh...
Scheme 10.3 Ppm Pd-catalyzed Suzuki reaction of electron-poor aryl chlorides...
Scheme 10.4 Ligand-free Suzuki–Miyaura coupling between arylboronic acids an...
Scheme 10.5 DNA-compatible Suzuki–Miyaura coupling.
Scheme 10.6 Pd/NHC-catalyzed Suzuki–Miyaura coupling.
Scheme 10.7 BaryPhos-facilitated asymmetric Suzuki–Miyaura cross-coupling.
Scheme 10.8 Ligand-free Suzuki–Miyaura coupling of amides via C–N cleavage....
Scheme 10.9 Base-free desulfitative coupling of thioethers with arylboronic ...
Scheme 10.10 Murahashi coupling between (hetero)aryl halides and organolithi...
Scheme 10.11 Negishi cross-coupling “on water” or in deep eutectic solvent....
Scheme 10.12 Negishi coupling under micellar catalysis using Fe/ppm Pd NPs....
Scheme 10.13 Ppm-catalyzed Stille coupling in water using triphenylphosphine...
Scheme 10.14 Stille coupling for the synthesis of isoflavones in water.
Scheme 10.15 Additive-free Pd-catalyzed Mizoroki–Heck cross-coupling of aryl...
Scheme 10.16 Cationic alkynyl Heck reaction between aryl triflates and alkyn...
Scheme 10.17 Pd-catalyzed carbonylative Heck coupling of aryl tosylates with...
Scheme 10.18 Ppm Pd-catalyzed Cu-free Sonogashira coupling.
Scheme 10.19 Microwave-assisted multiple Sonogashira couplings of poly-halog...
Scheme 10.20 Microwave-assisted one-pot, two-step Sonogashira-hydroarylation...
Scheme 10.21 Pd-catalyzed deacetonative coupling of aryl propargylic alcohol...
Scheme 10.22 Tsuji–Trost type allylic arylation of cinnamyl acetates with so...
Scheme 10.23 Ppm Pd-catalyzed cyanation of aryl/heteroaryl halides.
Scheme 10.24 Pd/C-catalyzed aminocarbonylation of aryl iodides with anthrani...
Scheme 10.25 Pd-catalyzed carboxylation of 5-bromo-furoic acid.
Scheme 10.26 Cu-catalyzed, Zn-mediated radical reductive arylation of styren...
Scheme 10.27 Fe-catalyzed reductive coupling of terminal (hetero)aryl alkene...
Scheme 10.28 Ir-catalyzed, photoreductive cross-coupling between nonactivate...
Scheme 10.29 Metal-free CDC between 2-aryl pyridines and cyclic or acyclic e...
Scheme 10.30 Pd-catalyzed α-arylation of (hetero)aryl ketones.
Scheme 10.31 Dehydrative cross-coupling of stabilized phosphonium ylides and...
Scheme 10.32 Visible-light photoredox-catalyzed decarboxylative radical coup...
Scheme 10.33 Oxidative decarboxylative coupling of α,α-difluoroarylacetic ac...
Scheme 10.34 Micellar-enabled ppm Pd-catalyzed Buchwald reaction.
Scheme 10.35
N
-arylation of oxetanylamines.
Scheme 10.36 Micelle-enabled
N
-arylation of sulfoximines.
Scheme 10.37 Cu-catalyzed
N
-arylation of amides, carbamates, and azoles.
Scheme 10.38 Cu-catalyzed
N
-1 regioselective arylation of indazoles.
Scheme 10.39 CuI/BMPO-catalyzed coupling of aryl halides with hydrazine hydr...
Scheme 10.40 Cu-catalyzed
N
-arylation of aliphatic amines.
Scheme 10.41 Cu-catalyzed selective
N
-arylation of aminophenols.
Scheme 10.42 Cu-catalyzed amination and hydroxylation of aryl halides.
Scheme 10.43 Room-temperature amination of chloroheteroarenes.
Scheme 10.44 Intramolecular cyclization involving Pd-catalyzed Tsuji–Trost
N
Scheme 10.45 Nickel-catalyzed allylic amination using allylic alcohols.
Scheme 10.46 α-Diimine Pd(II) complex-catalyzed C
–
S cross-coupling.
Scheme 10.47 Chemoselective Pd-protein OAC formation and protein
–
prote...
Scheme 10.48 Cu-catalyzed methylthiolation of aryl halides with dimethyl dis...
Scheme 10.49 Micellar-enabled nickel-catalyzed Migita-like C
–
S cross-c...
Scheme 10.50 Oxidative C
–
S cross-coupling of arylhydrazines with thiol...
Scheme 10.51 Cobalt-catalyzed aerobic cross-dehydrogenative coupling of C
–
...
Scheme 10.52 Reductive C
–
S coupling of (pseudo)halogenated
N
-heteroare...
Scheme 10.53 In(OTf)
3
-catalyzed, temperature-controlled regioselective benzy...
Scheme 10.54 Photoredox-catalyzed coupling of acyl oxime acetates with thiop...
Scheme 10.55 Pd-catalyzed C
–
P cross-coupling for the synthesis of aryl...
Scheme 10.56 Ru(II)-catalyzed microwave-promoted multiple C–H heteroarylatio...
Scheme 10.57 Micellar-enabled Ru(II)-catalyzed thioketone-directed C–H aryla...
Scheme 10.58 “On water” double C–H functionalization of ferrocene derivative...
Scheme 10.59 Ru(II) or Rh(III)-catalyzed C–H arylation of indoles with aryls...
Scheme 10.60 Cu-catalyzed α-(sp
3
)–H indolation of tetrahydroquinolines.
Scheme 10.61 Peptide macrocyclization via PA-directed intramolecular γ-C(sp
3
Scheme 10.62 Silver-catalyzed δ-C(sp
3
)–H heteroarylation of free alcohols vi...
Scheme 10.63 Photocatalyzed chemo-divergent C(sp
3
)–H arylation or
N
-dealkyla...
Scheme 10.64 Transition-metal-controlled selective C(sp
2
)–H mono- or di-olef...
Scheme 10.65 [Cp*RhCl
2
]
2
-catalyzed monoolefination.
Scheme 10.66 Temperature-controlled selective mono- or di-vinylation of 1-ph...
Scheme 10.67 Mn-catalyzed C–H enaminylation of 6-(1
H
-indol-1-yl)-purines wit...
Scheme 10.68 C2-
Z
-selective alkenylation of
N
-pyridyl-/
N
-pyrimidylindoles an...
Scheme 10.69 Oxidative acylation of electron-deficient heteroarenes with alk...
Scheme 10.70 Minisci aroylation of
N
-heterocycles using choline persulfate....
Scheme 10.71 C3–H decarboxylative acylation of quinoxaline-2(1
H
)-ones with α...
Scheme 10.72 Pd-catalyzed C(sp
2
)–H aroylation of Tyr-containing oligopeptide...
Scheme 10.73 Pd-catalyzed, primary amine-directed C2-regioselective C(sp
2
)–H...
Scheme 10.74 CeCl
3
·7H
2
O-catalyzed C(sp
2
)–CN bond construction on water.
Scheme 10.75 Mn(I)-catalyzed decarboxylative C(sp
2
)–H allylation.
Scheme 10.76 Water-enabled, Ni-catalyzed C3-allylation of (NH)-indoles with ...
Scheme 10.77
N
-benzylation/C–H benzylation of 2-morpholinoanilines.
Scheme 10.78 Ru(II)-catalyzed
ortho
-alkylation of benzoic acids via carboxyl...
Scheme 10.79 Enantioselective C(sp
2
)–H alkylation of indoles with α,β-unsatu...
Scheme 10.80 C(sp
2
)–H methylation and alkylation of pyrazinones and quinoxal...
Scheme 10.81 Minisci C–H alkylation of heteroarenes enabled by dual photored...
Scheme 10.82 Visible-light-induced direct C3-alkoxycarbonylmethylation and c...
Scheme 10.83 Micelle-enabled C(sp
3
)–H alkylation of methane and C2-C4 gaseou...
Scheme 10.84 Ni(II)-catalyzed, picolinamide (PA)-directed
ortho
-C(sp
2
)–H tri...
Scheme 10.85 Photocatalytic C(sp
2
)–H trifluoromethylation of a dipeptide.
Scheme 10.86 Rose Bengal/vitamin B
12
co-catalyzed radical C–H perfluoroalkyl...
Scheme 10.87
Ortho
-C–H amination of aryl amines with
O
-benzoylhydroxylamines...
Scheme 10.88 Nickel/photoredox
para
-C–H amination of aryl amines with pyrazo...
Scheme 10.89 Silver-catalyzed
para
-selective amination and aminative dearoma...
Scheme 10.90 Cu/Fe co-catalyzed intramolecular C(sp
2
)–H amination.
Scheme 10.91 Mn(I)-Catalyzed C–H amidation of 2-phenylpyridines and 2-pyrimi...
Scheme 10.92 Ir-catalyzed regioselective C–H sulfonamidation of 1,2,4-thiadi...
Scheme 10.93 Synthesis of quinoxaline-2,3(1
H
,4
H
)-diones via C3-hydroxylation...
Scheme 10.94 Ru-catalyzed tertiary- and benzylic-selective C(sp
3
)–H hydroxyl...
Scheme 10.95 Remote C(sp
3
)–H oxygenation of protonated aliphatic amines.
Scheme 10.96 α-Hydroxylation of β-keto esters and β-keto amides with CHP.
Scheme 10.97 C5–H bromination and iodination of 8-aminoquinoline amides unde...
Scheme 10.98 C(sp
2
)–H monofluorination of indoles and arenes with NFSI.
Scheme 10.99 Rh(III)-catalyzed C–H annulation of benzamides with alkynes.
Scheme 10.100 Ru(II)-catalyzed oxidative annulation of aromatic acids and al...
Scheme 10.101 Rh(III)-catalyzed C–H annulation for isoindolin-1-one synthesi...
Scheme 10.102 Ru(II)-catalyzed intramolecular hydroarylation of
O
-tethered o...
Scheme 10.103 Pd-catalyzed C–H functionalization of tryptamine derivatives w...
Scheme 10.104 C(sp
2
)–H activation/annulation of arenes with sulfoxonium ylid...
Scheme 10.105 Cp*Ir(III)-catalyzed C–H annulation of salicylaldehydes with α...
Scheme 10.106 Pd-catalyzed, Ag
2
O-mediated cyclization of
N
-aryl-2-aminopyrid...
Scheme 10.107 C–C allylation, C–C alkenylation, and C–C alkylation by chelat...
Scheme 10.108 RCM-triggered C–O uncaging reactions.
Scheme 10.109 Rh-catalyzed redox-neutral C–O cleavage of lignin model substr...
Scheme 10.110 Electrochemical oxidation of alcohols in water.
Scheme 10.111 Electro-oxidation of primary amines and selective semi-dehydro...
Scheme 10.112 Electrochemical-induced hydroxylation of aryl halides using ai...
Scheme 10.113 NHC-based iridium catalysts for hydrogenation and dehydrogenat...
Scheme 10.114 Cu-catalyzed chemoselective reduction of
N
-heteroaromatics wit...
Scheme 10.115 Mechanochemical, water-assisted ATH of ketones.
Scheme 10.116 Pd-catalytic
N
-cyclohexylation of α-amino acids/small peptides...
Scheme 10.117 Green synthesis of triaryl phosphates with POCl
3
in water.
Scheme 10.118 Phenolic
O
-glycosylation of small molecules.
Scheme 10.119 Base-promoted selective amination of polyhalogenated pyridines...
Scheme 10.120 Bu
4
NHSO
4
-catalyzed direct
N
-allylation of pyrazole and its der...
Scheme 10.121 DBSA-catalyzed regioselective dehydrative Friedel–Crafts aryla...
Scheme 10.122 Amphiphilic indoles as efficient phase-transfer catalysts for ...
Scheme 10.123 Radical deiodination-deuteration reaction of alkyl and aryl io...
Scheme 10.124 “On water” nitration of tyrosines and phenols.
Scheme 10.125 Nucleophilic additions of organometallic compounds to imines a...
Scheme 10.126 One-pot tandem alcohol oxidation and nucleophilic addition.
Scheme 10.127 Catalyst-free nucleophilic addition of thiols to silyl glyoxyl...
Scheme 10.128 Palladium-catalyzed addition for the synthesis of 3-aroyl coum...
Scheme 10.129 “All-water” synthesis of α,α-difluoro-β-aminoketones, and gem-...
Scheme 10.130 Indium-mediated Reformatsky reaction of iododifluoroketones wi...
Scheme 10.131 Cu-catalyzed enantioselective Henry reaction of β,γ-unsaturate...
Scheme 10.132 Direct conjugate additions using aryl and alkyl halides in air...
Scheme 10.133 Photocatalyzed
C
-terminal decarboxylative conjugation addition...
Scheme 10.134 Metallaphotoredox-catalyzed conjugation addition of aromatic b...
Scheme 10.135 Synthesis of β-aminosulfonyl fluorides via water-accelerated N...
Scheme 10.136 Catalyst- and reagent-free 1,6-hydrophosphonylation of
p
-quino...
Scheme 10.137 Photocatalyzed
Z
-selective radical addition of diaryl phosphin...
Scheme 10.138 Mn(III)-mediated decarboxylative hydroxysulfonylation of arylp...
Scheme 10.139 Micelle-enhanced auto-oxidative radical hydroxysulfenylation o...
Scheme 10.140 Radical dioxygenation of styrenes with molecular oxygen and NH...
Scheme 10.141 Phenylglyoxylic acid-initiated photochemical hydroacylation of...
Scheme 10.142 NBS-mediated one-pot oxyfunctionalization of styrenes.
Scheme 10.143 Eosin Y-catalyzed remote 1,5-trifluoromethylthio-sulfonylation...
Scheme 10.144 Cu(OTf)
2
/SIPHOS-catalyzed hydroboration of internal alkynes.
Scheme 10.145 Pd-catalyzed hydroxycarbonylation of alkynes with CO and H
2
O....
Scheme 10.146 Ligandless Pd-catalyzed direct α,β-homodiarylation of vinyl es...
Scheme 10.147 Micellar- and microwave-facilitated hydroformylation of termin...
Scheme 10.148 NiAAC for the synthesis of 1,5-disubstituted 1,2,3-triazoles....
Scheme 10.149 Regioselective synthesis of
N
2
-carboxyalkylated- and free 2
H
-1...
Scheme 10.150 One-pot three-step “all-water” synthesis of bis(hydroxymethyl)...
Scheme 10.151 Synthesis of spiro(indoline-2,3’-hydropyridazine) via “on-wate...
Scheme 10.152 Photochemical generation of cyclopentadiene and subsequent D–A...
Scheme 10.153 Silver-mediated synthesis of axially chiral vinylallenes and s...
Scheme 10.154 Cu-catalyzed stereoselective [4 + 2] cycloaddition of β,γ-unsa...
Scheme 10.155 Pd
-
catalyzed annulation of
ortho
-halobenzaldehydes with intern...
Scheme 10.156 Ni(II)-catalyzed [5 + 1] annulation of 2-carbonyl-1-propargyli...
Scheme 10.157 Ir-catalyzed enantiospecific hydrogen borrowing annulation.
Scheme 10.158 DEA-catalyzed cyclization of 2-aminobenzonitrile and CO
2
.
Scheme 10.159 Synthesis of monobromo- and multibromobenzoxazines via cycliza...
Scheme 10.160 Radical cyclization of enynes/dienes with alcohols.
Scheme 10.161 Radical cyclization of 1,6-enynes for the selective and switch...
Scheme 10.162 Radical cyclization of 2-arylbenzoimidazoles with unactivated ...
Scheme 10.163 Visible light-induced phosphorylation/cyclization of methylthi...
Scheme 10.164 Photo-induced radical addition–translocation–cyclization react...
Scheme 10.165 Water-promoted visible light-induced iodine atom transfer cycl...
Scheme 10.166 [2 + 2 + 1 + 1] cycloaddition of ketones with NH
4
Cl under CO
2
...
Scheme 10.167 Solvent-controlled selective formation of substituted thiazole...
Scheme 10.168 Four-component condensation between secondary amines, CS
2
, for...
Scheme 10.169 Visible light-promoted three-component reaction between Katrit...
Scheme 10.170 Ultrasound-assisted multicomponent synthesis of 4
H-
pyrans in w...
Scheme 10.171 Ultrasound-promoted one-pot four-component synthesis of 3,5-di...
Scheme 10.172 Catalyst-free one-pot synthesis of 2
H
-furo[3,2-
c
]chromene-2,4(...
Scheme 10.173 Elemental sulfur-based multicomponent synthesis of thioureas....
Scheme 10.174 Photomicellar-catalyzed synthesis of amides from isocyanides....
Scheme 10.175 Cu-catalyzed three-component synthesis of substituted 4-quinol...
Scheme 10.176 Cu(I)-catalyzed 6-
endo-dig
cyclization of terminal alkynes, 2-...
Scheme 10.177 Multicomponent bifunctionalization of methyl ketones enabled b...
Scheme 10.178 Multicomponent organocatalytic allylation.
Scheme 10.179 Pd/C-catalyzed domino synthesis of ureas using chloroform as t...
Scheme 10.180 Pd(II)-catalyzed four-component domino synthesis of aromatic e...
Scheme 10.181 Pd-catalyzed divergent synthesis of furans and pyrroles via ta...
Scheme 10.182 Pd-catalyzed cascade reaction to imidazo[1,2-
a
]pyridazines.
Scheme 10.183 Rh-catalyzed highly branch-selective hydroaminomethylation (HA...
Scheme 10.184 Cu-catalyzed 6-
endo-dig
cyclization and C(sp
2
)–O coupling of 2...
Scheme 10.185 Water-enabled asymmetric cross-reaction of α-keto acids with α...
Scheme 10.186 B
2
(OH)
4
-mediated one-pot synthesis of tetrahydroquinoxalines f...
Scheme 10.187 Catalyst-free cascade synthesis of 3-hydroxyisoindolinones fro...
Scheme 10.188 Comparison of sequential and cooperative (simultaneous) isomer...
Scheme 10.189 Micellar-catalyzed tandem Sonogashira/Heck/1,4-addition/hydrat...
Scheme 10.190 Sequential Ni-catalyzed Suzuki–Miyaura coupling and enzymatic ...
Scheme 10.191 Micellar-enabled one-pot Heck/lipase hydrolysis, RCM/esterase ...
Scheme 10.192 Cooperative chemoenzymatic synthesis of
N
-heterocycles via syn...
Scheme 10.193 Uncatalyzed oxygenative cleavage of inert C–N bond with concom...
Scheme 10.194 Clean preparation of quinolin-2-yl substituted ureas from quin...
Scheme 10.195 Electrochemical bromination/semi-pinacol rearrangement of ally...
Scheme 10.196 Electrocatalytic Achmatowicz reaction for the synthesis of hyd...
Scheme 10.197 Rh-catalyzed synthesis of seleno-ketals via carbene transfer r...
Scheme 10.198 Synthesis of 2,2-disubstituted indolin-3-ones via Rh-carbenoid...
Scheme 10.199 Difluoromethylation of alcohols with TMSCF
2
Br via a difluoroca...
Scheme 10.200 Blue light-induced cyclopropenizations, cyclopropanation, and ...
Scheme 10.201 Synthesis of amides via their acid chlorides in aqueous TPGS-7...
Scheme 10.202 COMU-mediated amide condensation in aqueous micellar solution....
Scheme 10.203 AMP
im1
-mediated amine condensation under surfactant- and base-...
Scheme 10.204 Electrochemical
N
-acylation of amines with carboxylic acids.
Scheme 10.205 Photochemical
N
-acylation of amines with carboxylic acids.
Scheme 10.206 Solvent-controlled selective synthesis of amides and thioureas...
Guide
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Green Solvents in Organic Synthesis
Edited by
Xiao-Feng Wu, Zhiping Yin, Liang-nian He, and Feng Wang
Editors
Prof. Xiao-Feng WuDalian Nat. Laboratory for Clean EnergyDalian Institute of Chemical Physics Chinese Academy of ScienceDalian 116023China
and
Leibniz-Institut Für Katalyse e.V.Albert-Einstein-Straβe 29a18059 RostockGermany
Prof. Dr. Zhiping YinJiangsu UniversitySchool of PharmacyZhenjiang 212013China
Prof. Dr. Liang-Nian HeNankai UniversityCollege of ChemistryInstitute of Elemento-organic ChemistryTianjin 300071China
Prof. Feng WangDalian Nat. Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of ScienceDalian 116023China
Cover Image: © Iana Kunitsa/Getty Images
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Print ISBN: 978-3-527-35200-5ePDF ISBN: 978-3-527-84192-9ePub ISBN: 978-3-527-84193-6oBook ISBN: 978-3-527-84194-3
1Recent Achievements in Organic Reactions in Alcohols
Lan Zhao1, Man Zhao1, Meng-Ge Wei2, Hong-Ru Li2, and Liang-Nian He1
1Nankai University, College of Chemistry, State Key Laboratory and Institute of Elemento-Organic Chemistry, 94 Weijin Road, Nankai District, Tianjin, 300071, China
2Nankai University, College of Pharmacy, No 38 Tongyan Road, Jinnan District, Tianjin, 300353, China
1.1 Introduction
Almost all manufacturing and processing industries now rely on the extensive use of solvents, and conventional synthesis depends heavily on environmentally incompatible organic solvents [1]. Most often, the solvents used in organic synthesis are volatile, so they can be removed from the reaction mixture by simple evaporation. The widespread use of these volatile organic solvents raises environmental concerns due to their intrinsic properties. With the growing awareness of the impact of solvents on environmental pollution, energy use, on-air quality, and climate change, sustainable solvents are a topic of increasing interest to the science community and the chemical industry [2].
Alcohols are a more desirable class of green solvents used in a wide range of organic reactions. In the last 15 years, alcohols have started to attract attention as alternatives to traditional organic solvents. These alcohols are able to work as solvents in general and include monohydric alcohols (methanol, ethanol, isopropanol, etc.), dihydric alcohols (ethylene glycol), tertiary alcohols (glycerol), fluorinated alcohols (2,2,2-trifluoroethanol [TFE], hexafluoroisopropanol [HFIP]), perfluoro tert-butyl alcohol [PFTB]), and polymers (polyethylene glycol [PEG], polypropylene glycol [PPG]), as shown in Scheme 1.1. Alcohols are typical proton-polar solvents and are widely used as inexpensive general solvents. The physical and chemical properties of some alcohols are depicted in Table 1.1[3].
Nowadays, numerous solvent selection guides have emerged from the pharmaceutical industry, such as those from Pfizer [4], GlaxoSmithKline (GSK) [5], and Sanofi [6]. In this regard, Table 1.2 lists several commonly used alcohols evaluated by selected guidelines in Table 1.2[2]. As a consequence, most of the several short-chain aliphatic alcohols appear to be the preferred solvents from a green chemistry perspective. High-boiling alcohols, glycerol, PEG, and PPG are also considered green solvents for various reactions. Furthermore, fluorinated alcohols are frequently used as solvents in chemical reactions due to their unique properties.
Scheme 1.1 Structure of alcohols.
Table 1.1 Physical and chemical properties of alcohols [3].
Alcohol properties
Methanol
Ethanol
2-propanol
Ethylene glycol
PEG-400
Glycerol
TFE
HFIP
Melting point (°C)
−98
−114
−89.5
−13
64–66
18
−44
−4
boiling point (°C)
65.4
78
82.5
197.6
>250
290
73
58
Relative density (g/mL)
0.791
0.789
0.786
1.113
1.27
1.25
1.391
1.596
Dielectric constant
32.7
24.6
19.9
37.7
—
42.5
24.5
16.7
Dipole moment (D)
1.69
1.7
1.65
2.31
—
2.56
0.61
0.61
Viscosity (mpa·s)
0.59 (20 °C)
1.07 (20 °C)
2.43 (20 °C)
25.66 (16 °C)
—
1.41*10
3
(20 °C)
—
—
Flash point (°C)
11.1
12.0
11.7
111.1
270.0
177.0
29.0
4.4
Surface tension (mN/m)
22.7
22.3
22.6
46.5
—
63.4
16.1
14.1
pKa (25 °C)
15.2
15.9
17.1
14.2
—
14.2
12.4
9.3
Polarizability (
π
*)
0.63
0.54
0.48
0.92
0.91
1.04
0.73
0.65
Hydrogen-bond donor (
α
)
0.93
0.83
0.76
0.90
0.31
0.93
1.51
1.96
Hydrogen-bond acceptor (
β
)
0.62
0.77
0.95
0.52
0.75
0.67
0.18
0.03
Polarity
12.3
8.8
6.1
11.0
—
12.1
10.2
11.8
Hydrogen bonding forces
22.3
19.4
16.4
26.0
—
29.3
—
—
Table 1.2 Guidelines for solvents for common alcohols.
Solvent
Pfizer
a)
GSK
b)
Sanofi
c)
Methanol
Preferred
Some issues
Recommended
Ethanol
Preferred
Some issues
Recommended
1-Propanol
Preferred
Some issues
Recommended
2-propanol
Preferred
Some issues
Recommended
1-Butanol
Preferred
Few issues
Recommended
2-Butanol
–
Few issues
Recommended
tert
-Butanol
Preferred
Some issues
Substitution advisable
Ethylene glycol
Usable
–
Substitution advisable
2-Methoxyethanol
–
Major issues
Substitution requested
Benzyl alcohol
–
–
Substitution requested
a) Selection guide by Pfizer.
b) GSK’s solvent selection guide.
c) Sanofi’s solvent selection guide.
Monohydric alcohols are organic compounds containing one hydroxyl group, including methanol, ethanol, and isopropanol. They are the most commonly used solvents in the thermochemical processing of lignocellulose due to their easy recovery and low cost. These alcohols have similar solvent properties, such as solvent strength, dielectric constant, critical point, and hydrogen supply capacity. They are usually soluble in polar solvents such as water, ether, and acetone but not in non-polar solvents such as petroleum ether. The hydroxyl groups in monohydric alcohol molecules give them polarity and can form hydrogen bonds with other polar molecules, resulting in high boiling points, melting points, and surface tension. These alcohols can be obtained from various sources such as fossil fuels, biomass, and waste. Methanol can be used in the production of other chemicals such as formaldehyde, methyl methacrylate, and dicarboxylic acid. Ethanol has wide applications in pharmaceuticals, beverages, coatings, cosmetics, and spices. Ethanol can be used to produce chemicals such as ethyl acetate, vinyl acetate, and acetaldehyde. Isopropanol can be used to produce plastics, paints, coatings, and solvents. It can also be used to prepare other chemicals, such as acetone and methyl isopropanol. They have low toxicity and are important clean fuels that can replace traditional fuels [1].
Ethylene glycol, a colorless, odorless, relatively non-volatile, low hygroscopic, and low-viscosity liquid, is the simplest representative of 1,2-diols. Owing to its unique structure, that is, two hydroxyl groups (OH) at adjacent positions along the hydrocarbon chain, allows it to engage in reactions such as esterification, dehydration, oxidation, and halogenation. In terms of solubility, ethylene glycol is completely miscible with numerous polar solvents (such as water, alcohols, glycol ethers, and acetone), but only slightly soluble in nonpolar solvents such as benzene, toluene, dichloroethane, and chloroform. Other than that, it is difficult to crystallize, but becomes highly viscous supercooled mass that solidifies to deliver a glassy substance upon gradual cooling. With regard to toxicity, ethylene glycol is inherently low in toxicity, but can yield toxic metabolites (Oral-rat LD50: 4700 mg/kg; Oral-mouse LD50: 5500 mg/kg) [7].
Glycerol is a ternary alcohol derived from biomass, which can be obtained from biodiesel production as a coproduct at a low price [8]. It has the same solubility as polar solvents such as water, DMSO, and DMF. In addition, it is immiscible with some common organic solvents such as hydrocarbons, ethers, and esters, which allows the reaction products to be separated by simple liquid–liquid phase extraction when using glycerol as a solvent. Glycerol is nonvolatile at atmospheric pressure and has a high boiling point (290 °C), so the reaction products can be separated using distillation techniques. Compared to most organic solvents, glycerol is a nontoxic (LD50 [rat oral] = 12 600 mg/kg), biodegradable, and nonflammable solvent that does not require special handling precautions or storage [9]. Glycerol has a greater polarity value (π* = 1.04) than other alcohols, as listed in Table 1. Glycerol molecules contain three hydroxyl groups capable of forming hydrogen bonds with reactants or intermediates. The hydrogen bonding force (29.3) is relatively high compared to other alcohols, as shown in Table 1.1. This strong hydrogen bonding network presumably plays a significant role in facilitating organic synthesis. These characteristics of glycerol render it widely used as an environmentally benign solvent in organic chemistry. In this context, glycerol mainly has four applications in organic reactions: (i) working as a promoting medium for organic synthesis, (ii) serving as a solvent to improve the product selectivity, (iii) enhancing the separation of products, and (iv) facilitating catalyst design and the recovery of catalytic systems. However, there also are some limitations of using glycerol as a solvent. First, its high viscosity can cause poor mass diffusion of the reactants in the medium, eventually leading to reduced reactivity. Second, the three hydroxyl groups of glycerol may provide coordination sites that may cause deactivation of specific organometallic complexes [10].
PEGs are also considered suitable alternatives to conventional organic solvents due to their attractive physicochemical properties (e.g. chemically inert, thermally stable, and nontoxic). In particular, PEGs are stable even at high temperatures up to 150–200 °C. [11]. Low-molecular-weight PEGs, such as PEG-300, have a greater polarity value (π* = 0.91) than methanol (0.63) as listed in Table 1.1. The hydrogen bond accepting ability (β = 0.75) is similar to that of methanol (0.62), while the hydrogen bond donating ability (α = 0.31) is less than that of methanol (0.93) [11]. As a hydrophilic oligomer, PEG is readily soluble in water and most organic solvents, such as toluene, methylene chloride, alcohols, and acetone; however, it is insoluble in aliphatic hydrocarbons such as hexane, cyclohexane, or ether. Liquid PEG is proportionally miscible with water, and solid PEG with a higher molecular weight is also extremely soluble in water [12]. For example, PEG-2000 has a solubility of about 20% in water at 60 °C. Water-soluble PEG is considered a cosolvent for organics in water, because it can contribute to a significant reduction in the polarity of aqueous solutions, which can be used as an alternative to other solvents such as ionic liquids, supercritical carbon dioxide, and micellar systems for reactions such as substitution, reduction, oxidation, and conventional or free-phase transfer catalysts (PTCs). PEGs as linear counterparts of crown ethers, are considered “host” solvents with regard to their ability to coordinate with metal cations to form complexes that transfer such cations from the aqueous phase to the organic phase. In order to remain electrically neutral, the PEG–metal complex has to carry the equivalent anion into the organic phase, enabling the anion to react with the organic reactants, so that PEGs can act as PTCs. Several factors influence the catalytic activity such as PEG molecular weight, chain end effects, and the nature of the relevant cations and anions [13].
In coordination with metals, PEGs have a more flexible structure compared to crown ether. Crown ether metal complexation depends on the size of the crown center cavity (fixed size). Whereas PEGs show a more flexible selectivity in the binding of metal cations of different sizes, as a result of the variation in the PEG helical conformation. Hence, PEG can coordinate metal cations with different sizes. Overall, PEG offers a more flexible structure for metal cation complexation. Besides, PEG complexation can also bring significant cost savings in extraction compared to crown ether complexation [14].
PPG is a viscous liquid with negligible vapor pressure, which is stable under normal reaction conditions and is easily recoverable. The majority of commercially available PPG, in contrast to PEG, has a molecular weight ranging from 250 to 4000 Da and is a viscous liquid. While PPG has an inverse relationship with temperature and solubility, low-molecular-weight PPG-250 Da to PPG-425 Da are soluble in water, and such solubility rapidly decreases as the molecular weight increases. These physical characteristics will restrict the use of PPG as a reaction medium because it is considerably more hydrophobic than PEG [15].
The use of fluorinated solvents as chemical reaction media in place of traditional volatile organic solvents has increased significantly. Fluorinated alcohols have unique physicochemical properties, including lower boiling point, higher melting point, high polarity, high hydrogen bond donor capacity, high ionizing power, and solvation capacity [16]. Among several fluorinated alcohols, the most commonly used and cheapest ones are TFE and HFIP, which have reached commercial scale and are often used as cosolvents, catalysts, or additives in addition reactions, condensation reactions, and ring-opening reactions [17]. Reactions in fluorinated solvents are usually highly selective, with no other effluents, so the product is easily separated and the solvent can be recovered by distillation for reuse. Moreover, due to the weak acidity (pKa = 12.4 for TFE, pKa
