The Wittig olefination reaction and modifications involving phosphoryl-stabilized carbanions.pdf
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1、Subscriber access provided by ADOLOR CORPORATIONChemical Reviews is published by the American Chemical Society.1155 SixteenthStreet N.W.,Washington,DC 20036The Wittig olefination reaction and modifications involvingphosphoryl-stabilized carbanions.Stereochemistry,mechanism,and selected synthetic asp
2、ectsBruce E.Maryanoff,and Allen B.ReitzChem.Rev.,1989,89(4),863-927 DOI:10.1021/cr00094a007Downloaded from http:/pubs.acs.org on January 30,2009More About This ArticleThe permalink http:/dx.doi.org/10.1021/cr00094a007 provides access to:Links to articles and content related to this articleCopyright
3、permission to reproduce figures and/or text from this articleChem.Rev.1989,89,863-927 863 The Wittig Olefination Reaction and Modifications Involving Selected Synthetic Aspects Phosp horyl-Sta bilized Carbanions.Stereochemistry,Mechanism,and BRUCE E.MARYANOFF and ALLEN B.REITZ Chemical Research Depa
4、rtment,Janssen Research Foundation,Spring House,Pennsylvania 19477 Received May 23,1988(Revised Manuscript Received January 17,1989)Contents I.Introduction 11.Phosphonium Ylides A.Stereochemistry and Mechanism 1.1,2-Oxaphosphetanes and Betaines as 2.Nonstabilized Ylides 3.Stabilized and Semistabiliz
5、ed Ylides 4.General Discussion Stereochemistry 1.Wittig Reactions with Anomalous 2.Selected Synthetic Applications Intermediates B.Selected Synthetic Aspects Involving Stereochemistry(1979-1987)111.Phosphoryl-Stabilized Carbanions A.Phosphonate Carbanions 1.Mechanistic Aspects 2.Preparation of Phosp
6、honate Reagents 3.Different Types of Phosphonates in 4.Newer Reaction Technologies 5.Intramolecular Reactions B.Phosphine Oxide Carbanions C.Other Phosphoryl and Thiophosphoryl Synthesis Carbanions IV.Concluding Remarks A.Phosphonium Ylides B.Phosphoryl-Stabilized Carbanions V.Acknowledgments VI.Ref
7、erences and Notes 863 863 864 864 868 874 876 88 1 88 1 896 90 1 902 902 903 904 910 91 1 912 916 916 916 917 917 917 I.Introduction There was a time in organic chemistry when the olefination of ketones and aldehydes was faced with some trepidation.Because of limited synthetic meth-ods,as recently a
8、s 30 years ago,the chemist had to contend with two isomer problems,that of double-bond position and that of double-bond geometry.Landmark paperslia published by Wittig and co-workers in the early 1950s disclosed a means for the preparation of alkenes with unambiguous positioning of the double bond,b
9、ased on the reaction of aldehydes or ketones with phosphonium ylides(eq 1).Because of its effec-tiveness and generality,the Wittig reaction became widely used and thereby changed the course of olefin synthesis for all time.3 Indeed,the development of the Wittig reaction helped to usher in the modern
10、 era of 0009-266518910789-0863$06.50/0 organic synthesis,wherein positional selectivity,ste-reoselectivity,and chemoselectivity are of paramount importance to,and under the sensitive and responsive control of,the synthetic pratitioner.The 1960s witnessed major advances in the Wittig reaction and in
11、Wittig-style olefinations.The stereo-chemistry and mechanism of the Wittig reaction were investigated,and a complementary reaction involving phosphoryl-stabilized carbanions was developed.Al-though several reviews have documented the state of the Wittig and related reactions,up to as recently as 198
12、5,$17 key recent facets,especially in the areas of stereochemistry and mechanism,have inspired us to compose this article.Our emphasis will be placed on information added to this topic from 1978 to the present.Also,we will present new synthetic highlights from this period of time to provide a full,u
13、p-to-date discussion.This review will be limited to reactions of aldehydes and ketones;it will not deal with ester-or amide-type substrates.*I I.Phosphonium Yiides The conventional Wittig reaction entails the reaction of a phosphonium ylide with an aldehyde or a ketone(eq 1).This olefination method
14、has enjoyed wide-R R O+(R73P=C/Y-”X;R+(R73P=0(I)aldehyde phosphorus alkenes phosphlne or ketone gide oxide spread prominence and recognition because of its sim-plicity,convenience,and efficiency.“14 Yet,despite such venerable attributes,the attractiveness of the Wittig reaction in synthesis may ofte
15、n hinge on effective stereocntrol.JJJ High selectivity for(2)-or(E)-alkenes is available,depending on the particular cir-cumstances,such as the type of ylide,type of carbonyl compound,or reaction conditions.8J1 Phosphorus ylides have been loosely classified ac-cording to their general reactivity.“St
16、abilized”ylides have strongly conjugating substituents(e.g.,COOMe,CN,or S0,Ph)on the ylidic carbon and usually favor the production of)-alkenes,“semistabilized”(or“moderated”)ylides bear mildly conjugating substitu-ents(e.g.,Ph or allyl)and often give no great preference one way or the other,and“non
17、stabilized”ylides lack such functionalities and usually favor(2)-alkenes.Of course,there are notable,if not glaring,exceptions to these generalized stereoselectivities,some of which will 0 1989 American Chemical Society 864 Chemical Reviews.1989.Vol.89.No.4 Maryanoff and Rekz persisted with respect
18、to this high preference for con-trathermodynamic(2)-alkenes in,for example,reactions of triphenylphosphorus nonstabilized ylides with al-dehydes.This characteristic has attracted the curiosity of chemists for decades and stimulated attempts to arrive at a truly satisfying mechanistic explanation.The
19、 other two classes of ylides are also interesting from a mechanistic standpoint.For example,one may wonder:Is the strong preference for the(E)-alkenes with many stabilized ylides a consequence of kinetic or thermodynamic control?To define the source of such stereocontrol,organic chemists have resort
20、ed to mech-anistic studies and the pursuit of reaction intermediates.These two subjects will be addressed in section 1I.A.1.1,2-Oxaphosphetanes and Betaines as Intermediates Regarding intermediates in the reaction,Wittig first mentioned a four-membered cyclic phosphorane(a 1.2-oxaphosphetane)early o
21、n$however,he soon came to favor a zwitterionic phosphorus betaine(eq 2)?,21 P Bruce Maryanoff was born in Philadelphia,PA,in 1947 and has reslded in that region for most of his life.He received his B.S.(1969)and Ph.D.(1972,with Professor Robert Hutchins)degrees from Drexei University.Afler postdocto
22、ral studies with Professor K u l Mklow at Princeton University(1972-1974).ha jo4ned the staff of McNeil Laboratories(renamed McNeil aceutical in 1980).Following reorganization of the Johnson 8 Johnson pharmaceutical Sector in 1987.he became part of the Belgium-headquarlered Janssen Research Foundati
23、on(JRF)Worldwue.He now holds the position of Distinguished Research Fellow in the laboratories of JRF-US in Spring House.PA.His major research interests have entailed stereochemistry and mechanisms of organic reactions.conformational analysis.monosaccharide chemistry,heterocyclic chemistry.selective
24、 reduction processes.and drugs for treating disorders of the central nervous system.He has published over 80 scientific papers,is an inventor on 15 US.Patents.and was recipient 01 the 1984 Section Award of the American Chemical Society,Philadelphia Section.He dedicates ais review to his wife Cynthia
25、.f Ailen Reitz was born in Aiameda.CA.in 1956.He received his B.A.degree(1977)from the University of California at Santa Barbara and his Ph.D.degree(1982)from the University of CalC fornia at San Diego,working with Professor Murray Goodman.Afler a 1-year postdoctoral stint with Dr.Maryanoff at McNei
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