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The latest volume in this series for organic chemists in industry presents critical discussions of widely used organic reactions or particular phases of a reaction. The material is treated from a preparative viewpoint, with emphasis on limitations, interfering influences, effects of structure and the selection of experimental techniques. The work includes tables that contain all possible examples of the reaction under consideration. Detailed procedures illustrate the significant modifications of each method.

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Table of Contents

Cover

Title Page

Copyright

Introduction to the Series Roger Adams, 1942

Introduction to the Series Scott E. Denmark, 2008

Preface to Volume 90

About the Author

Chapter 1: The Catalytic, Enantioselective Michael Reaction

Acknowledgments

Introduction

Mechanism and Stereochemistry

Scope and Limitations

Applications to Synthesis

Comparison with Other Methods

Experimental Conditions

Experimental Procedures

Tabular Survey

References

Supplemental References for Table 1A

Supplemental References for Table 1B

Supplemental References for Table 1C

Supplemental References for Table 1D

Supplemental References for Table 2A

Supplemental References for Table 2B

Supplemental References for Table 2D

Supplemental References for Table 3A

Supplemental References for Table 3B

Supplemental References for Table 3C

Supplemental References for Table 3D

Supplemental References for Table 3E

Supplemental References for Table 4A

Supplemental References for Table 4B

Supplemental References for Table 4C

Supplemental References for Table 4D

Supplemental References for Table 5A

Supplemental References for Table 5B

Supplemental References for Table 5C

Supplemental References for Table 5D

Supplemental References for Table 5E

Cumulative Chapter Titles By Volume

Author Index, Volumes 1–90

Chapter and Topic Index, Volumes 1–90

End User License Agreement

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Guide

Cover

Table of Contents

Preface

Begin Reading

List of Illustrations

Chapter 1: The Catalytic, Enantioselective Michael Reaction

Scheme 1

Scheme 2

Scheme 3

Scheme 4

Scheme 5

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Scheme 10

Scheme 11

Scheme 12

Scheme 13

Scheme 14

Scheme 15

Scheme 16

Scheme 17

Figure 1 Structure of (DHQ)

2

PHAL

Scheme 18

Scheme 19

Scheme 20

Scheme 21

Scheme 22

Scheme 23

Scheme 24

Scheme 25

Scheme 26

Scheme 27

Scheme 28

Scheme 29

Scheme 30

Scheme 31

Scheme 32

Scheme 33

Scheme 34

Scheme 35

Scheme 36

Scheme 37

Scheme 38

Scheme 39

Scheme 40

Scheme 41

Scheme 42

Scheme 43

Scheme 44

Scheme 45

Scheme 46

Scheme 47

Scheme 48

Scheme 49

Scheme 50

Scheme 51

Scheme 52

Scheme 53

Scheme 54

Scheme 55

Scheme 56

Scheme 57

Scheme 58

Scheme 59

Scheme 60

Scheme 61

Scheme 62

Scheme 63

Scheme 64

Scheme 65

Scheme 66

Scheme 67

Scheme 68

Scheme 69

Scheme 70

Scheme 71

Scheme 72

Scheme 73

Scheme 74

Scheme 75

Scheme 76

Scheme 77

Scheme 78

Scheme 79

Scheme 80

Scheme 81

Scheme 82

Scheme 83

Scheme 84

Scheme 85

Scheme 86

Scheme 87

Scheme 88

Scheme 89

Scheme 90

Scheme 91

Scheme 92

Scheme 93

Scheme 94

Scheme 95

Scheme 96

Scheme 97

Scheme 98

Scheme 99

Scheme 100

Scheme 101

Scheme 102

Scheme 103

Scheme 104

Scheme 105

Advisory Board

J

ohn

E. B

aldwin

P

eter

B

eak

D

ale

L. B

oger

André B. C

harette

E

ngelbert

C

iganek

D

ennis

C

urran

S

amuel

D

anishefsky

H

uw

M. L. D

avies

V

ittorio

F

arina

J

ohn

F

ried

J

acquelyn

G

ervay

-H

ague

H

einz

W. G

schwend

S

tephen

H

anessian

L

ouis

H

egedus

R

obert

C. K

elly

A

ndrew

S. K

ende

L

aura

K

iessling

S

teven

V. L

ey

J

ames

A. M

arshall

M

ichael

J. M

artinelli

S

tuart

W. M

c

C

ombie

J

errold

M

einwald

S

cott

J. M

iller

L

arry

E. O

verman

L

eo

A. P

aquette

G

ary

H. P

osner

T. V. R

ajan

B

abu

H

ans

J. R

eich

J

ames

H. R

igby

W

illiam

R. R

oush

T

omislav

R

ovis

S

cott

D. R

ychnovsky

M

artin

S

emmelhack

C

harles

S

ih

A

mos

B. S

mith

, III

B

arry

M. T

rost

J

ames

D. W

hite

P

eter

W

ipf

Former Members of the Board Now Deceased

R

oger

A

dams

H

omer

A

dkins

W

erner

E. B

achmann

A. H. B

latt

R

obert

B

ittman

V

irgil

B

oekelheide

G

eorge

A. B

oswell

, J

r

.

T

heodore

L. C

airns

A

rthur

C. C

ope

D

onald

J. C

ram

D

avid

Y. C

urtin

W

illiam

G. D

auben

R

ichard

F. H

eck

L

ouis

F. F

ieser

R

alph

F. H

irshmann

H

erbert

O. H

ouse

J

ohn

R. J

ohnson

R

obert

M. J

oyce

W

illy

L

eimgruber

F

rank

C. M

c

G

rew

B

laine

C. M

c

K

usick

C

arl

N

iemann

H

arold

R. S

nyder

M

ilán

U

skokovic

B

oris

W

einstein

Organic Reactions

Volume 90

Editorial Board

Scott E. Denmark, Editor-in-Chief

 

Jeffrey Aubé

Carl Busacca

Jin K. Cha

P. Andrew Evans

Paul L. Feldman

Dennis G. Hall

Paul J. Hergenrother

Donna M. Huryn

Jeffrey S. Johnson

Marisa C. Kozlowski

Gary A. Molander

John Montgomery

Steven M. Weinreb

 

Robert M. Coates, Secretary University of Illinois at Urbana-Champaign, Urbana, Illinois

 

Jeffery B. Press, Secretary Press Consulting Partners, Brewster, New York

 

Danielle Soenen, Editorial Coordinator

 

Landy K. Blasdel, Editorial Assistant

 

Dena Lindsay, Editorial Assistant

 

Linda S. Press, Editorial Consultant

 

Engelbert Ciganek, Editorial Advisor

 

Associate Editors

Luisa CarrilloEfraim ReyesUxue UriaJose L. Vicario

 

 

Copyright © 2016 by Organic Reactions, Inc. All rights reserved.

Published by John Wiley & Sons, Inc., Hoboken, New Jersey

Published simultaneously in Canada.

No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning, or otherwise, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA~01923, (978) 750-8400, fax (978) 750-4470, or on the web at www.copyright.com. Requests to the Publisher for permission should be addressed to the Permissions Department, John Wiley & Sons, Inc., 111 River Street, Hoboken, NJ 07030, (201) 748-6011, fax (201) 748-6008, or online at http://www.wiley.com/go/permission.

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Library of Congress Catalog Card Number: 42-20265

ISBN: 978-1-119-28144-3

Introduction to the Series Roger Adams, 1942

In the course of nearly every program of research in organic chemistry, the investigator finds it necessary to use several of the better-known synthetic reactions. To discover the optimum conditions for the application of even the most familiar one to a compound not previously subjected to the reaction often requires an extensive search of the literature; even then a series of experiments may be necessary. When the results of the investigation are published, the synthesis, which may have required months of work, is usually described without comment. The background of knowledge and experience gained in the literature search and experimentation is thus lost to those who subsequently have occasion to apply the general method. The student of preparative organic chemistry faces similar difficulties. The textbooks and laboratory manuals furnish numerous examples of the application of various syntheses, but only rarely do they convey an accurate conception of the scope and usefulness of the processes.

For many years American organic chemists have discussed these problems. The plan of compiling critical discussions of the more important reactions thus was evolved. The volumes of Organic Reactions are collections of chapters each devoted to a single reaction, or a definite phase of a reaction, of wide applicability. The authors have had experience with the processes surveyed. The subjects are presented from the preparative viewpoint, and particular attention is given to limitations, interfering influences, effects of structure, and the selection of experimental techniques. Each chapter includes several detailed procedures illustrating the significant modifications of the method. Most of these procedures have been found satisfactory by the author or one of the editors, but unlike those in Organic Syntheses, they have not been subjected to careful testing in two or more laboratories. Each chapter contains tables that include all the examples of the reaction under consideration that the author has been able to find. It is inevitable, however, that in the search of the literature some examples will be missed, especially when the reaction is used as one step in an extended synthesis. Nevertheless, the investigator will be able to use the tables and their accompanying bibliographies in place of most or all of the literature search so often required. Because of the systematic arrangement of the material in the chapters and the entries in the tables, users of the books will be able to find information desired by reference to the table of contents of the appropriate chapter. In the interest of economy, the entries in the indices have been kept to a minimum, and, in particular, the compounds listed in the tables are not repeated in the indices.

The success of this publication, which will appear periodically, depends upon the cooperation of organic chemists and their willingness to devote time and effort to the preparation of the chapters. They have manifested their interest already by the almost unanimous acceptance of invitations to contribute to the work. The editors will welcome their continued interest and their suggestions for improvements in Organic Reactions.

Introduction to the Series Scott E. Denmark, 2008

In the intervening years since “The Chief” wrote this introduction to the second of his publishing creations, much in the world of chemistry has changed. In particular, the last decade has witnessed a revolution in the generation, dissemination, and availability of the chemical literature with the advent of electronic publication and abstracting services. Although the exponential growth in the chemical literature was one of the motivations for the creation of Organic Reactions, Adams could never have anticipated the impact of electronic access to the literature. Yet, as often happens with visionary advances, the value of this critical resource is now even greater than at its inception.

From 1942 to the 1980's the challenge that Organic Reactions successfully addressed was the difficulty in compiling an authoritative summary of a preparatively useful organic reaction from the primary literature. Practitioners interested in executing such a reaction (or simply learning about the features, advantages, and limitations of this process) would have a valuable resource to guide their experimentation. As abstracting services, in particular Chemical Abstracts and later Beilstein, entered the electronic age, the challenge for the practitioner was no longer to locate all of the literature on the subject. However, Organic Reactions chapters are much more than a surfeit of primary references; they constitute a distillation of this avalanche of information into the knowledge needed to correctly implement a reaction. It is in this capacity, namely to provide focused, scholarly, and comprehensive overviews of a given transformation, that Organic Reactions takes on even greater significance for the practice of chemical experimentation in the 21st century.

Adams' description of the content of the intended chapters is still remarkably relevant today. The development of new chemical reactions over the past decades has greatly accelerated and has embraced more sophisticated reagents derived from elements representing all reaches of the Periodic Table. Accordingly, the successful implementation of these transformations requires more stringent adherence to important experimental details and conditions. The suitability of a given reaction for an unknown application is best judged from the informed vantage point provided by precedent and guidelines offered by a knowledgeable author.

As Adams clearly understood, the ultimate success of the enterprise depends on the willingness of organic chemists to devote their time and efforts to the preparation of chapters. The fact that, at the dawn of the 21st century, the series continues to thrive is fitting testimony to those chemists whose contributions serve as the foundation of this edifice. Chemists who are considering the preparation of a manuscript for submission to Organic Reactions are urged to contact the Editor-in-Chief.

Preface to Volume 90

What's in a name?

W. Shakespeare, Romeo and Juliet, (1595) act 2, sc. 2, l. 43

Name reactions! Organic chemists are obsessed with name reactions. Today one can find many compendia (and of course apps) and even an encyclopedia of name reactions, some of which such as “Strategic Applications of Named Reactions in Organic Synthesis” by László Kürti and Barbara Czakó provide excellent summaries of the genesis, mechanism, and applications of these celebrated transformations. In the preface to Volume 77 I wrote that

“the caché associated with a “name reaction” carries a special significance. Apart from the convenience of being able to identify a given transformation by a simple name and assign credit (whether deserved or not!) to specific individual or individuals, the designation of a name reaction implies a high standard of utility, generality or uniqueness.”

Of the 279 chapters published in the Organic Reactions series, 103 are based on name reactions and many others have since become name reactions such as “Palladium-Catalyzed Vinylation of Organic Halides” in Volume 27 by Richard F. Heck. In addition to the special significance of the transformation, name reactions also raise the obvious question, “Who is/was that individual”? Apart from historians of science, few practicing chemists and certainly most students actually know who these exceptional people are/were. This is certainly the case for Arthur Michael.

“Arthur Michael (1853-1942) was for many years the most versatile and productive American organic chemist, with unrivaled scope and a highly individual view of the theoretical basis of organic chemistry. The son of a prosperous family in Buffalo, New York, he was educated in Germany, Russia, and France and had no college or university degrees except for honorary doctorates. His chemical training abroad resulted in over sixteen papers from Germany starting in 1876 some with S. Gabriel of the University of Berlin faculty and some with other students. His scientific publications numbered 225, appeared over a period of nearly seven decades, and were published from Tufts College, Harvard, or private laboratories which he maintained on the Isle of Wight in 1890s and at Newton Center, Massachusetts, after 1912.”

D. S. Tarbell and A. T. Tarbell, “Essays on the History of Organic Chemistry in the United States, 1875-1955”, Folio Publishers: Nashville; 1986, p. 45.

Michael published his first paper on the eponymous reaction simultaneously in German and English in 1887. Ironically, this reaction had already been reported by Ludwig Claisen in 1883 and Michael acknowledged Claisen's priority but he substantially expanded its scope and generality. It can be argued that the Michael Reaction is the first name reaction to be ascribed exclusively to an American organic chemist.

It is therefore not surprising that two chapters covering the Michael Reaction have already appeared in the Organic Reactions series in Volumes 10 (the basic reaction) and 47 (the intramolecular version). The chapter that comprises the current volume by Efraím Reyes, Uxue Uria, Jose L. Vicario, and Luisa Carrillo represents the most advanced variant of this powerful reaction, namely, the catalytic, enantioselective Michael Reaction. The inherent ability of the Michael Reaction to create up to three contiguous stereogenic centers has clearly been recognized and over the course of the past decades, many investigators have learned to control the relative configurations of these newly formed centers. Moreover, the Michael Reaction, thanks in part to its exothermicity, is highly susceptible to catalysis, which in turn has stimulated an enormous amount of activity in the development of chiral catalysts to control both the relative and absolute configurations of the products.

Prof. Vicario and his team have composed an outstanding summary of the most important catalytic variants now available from metal catalysis to organocatalysis. In addition they have provided a detailed description of those pairwise combinations of Michael donor and Michael acceptor that are best suited for a given catalytic mode. The power of this reaction is beautifully illustrated by selected examples in the total synthesis of complex natural products. As is the hallmark of Organic Reactions chapters, the comprehensive coverage found in the Tabular Survey is organized (by donor and acceptor) so that the practitioner hoping to find analogies or precedent for their own work will be quickly directed to the appropriate needle in this massive haystack.

Volume 90 represents the twelfth single chapter volume to be produced in our 75-year history (the third in a row and fifth in the past eleven volumes!). Such single-chapter volumes represent definitive treatises on extremely important chemical transformations. The organic chemistry community owes an enormous debt of gratitude to the authors of such chapters for the generous contribution of their time, effort, and insights on reactions that we clearly value.

It is appropriate here to acknowledge the expert assistance of the entire editorial board, in particular Jeffrey Johnson and P. Andrew Evans who shepherded this chapter to completion. The contributions of the authors, editors, and the publisher were expertly coordinated by the board secretary, Robert M. Coates. In addition, the Organic Reactions enterprise could not maintain the quality of production without the dedicated efforts of its editorial staff, Dr. Danielle Soenen, Dr. Linda S. Press, Dr. Dena Lindsey, and Dr. Landy Blasdel. Insofar as the essence of Organic Reactions chapters resides in the massive tables of examples, the author's and editorial coordinators' painstaking efforts are highly prized.

Scott E. DenmarkUrbana, Illinois

Milan Radoje UskokovicJuly 14, 1924–May 11, 2015

Milan Uskokovic got much of his early life experiences in the crucible that was World War II in Yugoslavia. He promptly joined and fought with the resistance from 1941 through the balance of the conflicts. During this time he developed his characteristic thousand-yard stare, clearly evident in the picture overleaf from 1946.

About the Author

On Saturdays in the 70's at his home in Montclair, NJ, over glasses of doubly-distilled slivovitz and ice, he recollected about the chaos of the times and remembered “fondly” a short stint in a German POW camp in early 1945 from which he and his colleagues escaped. They told their captors that the resistance was nearby and they would soon be rescued. During the following night, their captors fled. Milan was also involved in rescues of downed American airmen in 1943 and 1944 in resistance-controlled territories. See the published description of “Operation Halyard” in Freeman, G. A., The Forgotten 500, NAL Caliber (Penguin Group), New York, 2007.

With the ending of hostilities and the beginning of rebuilding his country in 1946, Milan returned to the Polytechnic Institute of the University of Belgrade where he obtained his Diplomate degree in Chemical Engineering. During this period Milan met, studied with, and married a fellow chemical engineering graduate, his beloved Nada.

As Yugoslavia was rebuilt, Milan and Nada worked for several small firms supported by United Nations reconstruction funds, and Milan later landed a manufacturing job in chemistry at Pliva Pharmaceuticals in Zagreb.

In 1956 Milan was awarded a chemistry scholarship for doctoral studies at Clark University in Worcester, Massachusetts. Thanks to the efforts of US Senator Leverett Saltonstall (R-Massachusetts) who arranged for Milan and Nada to immigrate to the US for continued studies. Milan carried out his graduate work with Prof. Ralph I. Dorfman on biologically important steroids useful in the amelioration of pain, lowering blood pressure, and inhibiting contraception. He received his Ph. D. degree from both the Worcester Foundation for Biomedical Research and Clark University in 1960.

Nada and Milan then moved to New Jersey when Milan was offered a position at Hoffmann-LaRoche. Early projects included investigations of 9β,10α-retrosteroids related to dydrogesterone, 19-norsteroids, and azasteroids for a variety of uses, as well as heterocycles in the CNS area. The studies on heterocycles followed the legendary CNS discoveries by Roche's Dr. Leo Sternbach of Librium® (chlordiazepoxide) and Valium® (diazepam) fame.

With Drs. Arnold Brossi and Willi Leimgruber, Milan helped create the Department of Natural Products Chemistry, and began work on a number of biologically active alkaloids including isoquinolines and the important anti-malarial alkaloids which also possessed useful cardiovascular properties. Beginning in 1970, Milan and his group announced several partial and total syntheses of racemic and optically active (−)-quinine and (+)-quinidine. In addition, a technical synthesis was created to convert cheap natural (−)-quinine into the antiarrhythmic agent (+)-quinidine which was marketed as the slow-release glutaconate salt Duraquin® / Quinaglute®.

A collaboration between the Walter Reed Army Hospital and Hoffmann-LaRoche led to the introduction of trifluoromethyl derivatives of quinine and quinidine and eventually to mefloquine for chloroquin-resistant strains of malaria. Mefloquine, later marketed as Lariam®, is used for both the treatment and prevention of resistant forms of malaria and is still on the World Health Organization's List of Essential Medicines.

The latter half of Milan's career was dedicated to the biology and chemistry of vitamin D and its potent and active metabolites. He became a leading researcher in vitamin D endocrinology and chemistry and authored or co-authored 71 US patents in this area. Milan helped move 1α,25-dihydroxycholecalciferol (1α,25-DHCC), known as Rocaltrol® (calcitriol), from preclinical synthesis through clinical trials and to the marketplace in less than five years. He and his group carried out the syntheses, and in some cases the structure determinations, of various vitamin D3 metabolites. These and other related analogs were used as experimental treatments of metabolic bone diseases such as osteomalacia, osteopenia, and osteoporosis, as well as therapies for hyperproliferative diseases such as psoriasis, leukemias, and lymphomas. As an outgrowth of treating dialysis-induced hypocalcemia, Rocaltrol® (calcitriol) was also discovered to have synergetic immunosuppressive activity with Neoral® and Sandimmune® (cyclosporin A) in kidney transplant patients.

Other highlights in Milan's career:

Authored or co-authored over 130 US patents

Elected Vice-Chair 1978 and Chair 1979 of the Gordon Research Conference on Natural Products Chemistry

Inducted into the New Jersey Inventors Hall of Fame 1994

Served on six advisory or editorial boards of professional journals including Organic Reactions

Member of the American Chemical Society and the New York Academy of Sciences

Adjunct Professor of Chemistry at Stevens Institute of Technology, Hoboken, NJ

Regents Professor at the University of California, Berkeley, CA

Research Mentor at the Medical School of Brown University - A laboratory at Women & Infants Hospital of Rhode Island, affiliated with the medical school of Brown University, dedicated in honor of his research mentorship

Vice President of Chemistry at Bioxell S.p. A., Milan, Italy, from 2002-2010

Milan formally brought his illustrious career to a close when he retired in 2010.

He was predeceased by his son, Charles Uskokovic, in 2011 and by his wife Nada Uskokovic in 2015, a month before his own death.

Milan is survived by his daughters, Moira Bogrov, M.D., and her husband, Michael Bogrov, M.D.; and Lila Vidger, Ph.D., and her husband, Donald Vidger, M.D.; and by his grandchildren, Samuel and Caroline Bogrov and Madeleine, Linnea, and Nicholas Vidger. He is also survived by his sister, Mrs. Vuka Markovic of Belgrade, Serbia.

Though an émigré from far away and a very different era, Milan always wanted to be known as a member of America's greatest generation. As I look across his entire career – warrior, patriot, scientist, creator of healing medicines - in my opinion, he succeeded.

John J. Partridge, Ph.D., MRSC – Chapel Hill, North Carolina

George A. Boswell, Jr.January 26, 1932 – December 11, 2015

George Boswell was born on January 26, 1932 in Hayward, California. He grew up in near-by Castro Valley, graduated from Hayward High School, and then enrolled in the University of California, Berkeley, where he received both his undergraduate and Ph.D. degrees in chemistry, the latter in 1959.

As an undergraduate he worked full time for Colgate Palmolive. His graduate work was done under the supervision of William G. Dauben, a future Editor-in-Chief of Organic Reactions. He then worked for Shell Development Company in Emeryville, California and in 1961 was hired by DuPont in Wilmington, Delaware to apply the fluorine chemistry developed at DuPont, to the modification of steroids which was the subject of his Ph.D. thesis. This led to a collaboration with Syntex, a California-based drug company that specialized in steroids.

When DuPont entered the pharmaceutical business in 1970 with the purchase of Endo Laboratories of Long Island, New York, George was put in charge of the drug discovery group in the Central Research Department. This group was later transferred to the Medical Products Department, and eventually to the DuPont-Merck Pharmaceutical Company, a newly formed joint venture with Merck in 1991.

George retired in 1993 and moved to the northern Sierra Mountains of California with his wife Syble. There he enjoyed fishing and cross-country skiing. He also was an avid runner. The Boswells later moved to a retirement village in Reno, Nevada. George died on December 11, 2015 of brain cancer. He is survived by Syble, his wife of 63 years, four children, eight grand children, and one great-grand child.

George was an editor of Organic Reactions