Highly stereoselective aldol reactions of titanium enolates from ethyl alpha-silyloxyalkyl ketones

被引：29

作者：

Figueras, S ^{[1
]}

Martin, R ^{[1
]}

Romea, P ^{[1
]}

Urpi, F ^{[1
]}

Vilarrasa, J ^{[1
]}

机构：

[1] UNIV BARCELONA,FAC QUIM,DEPT QUIM ORGAN,E-08028 BARCELONA,CATALONIA,SPAIN

来源：

TETRAHEDRON LETTERS | 1997年 / 38卷 / 09期

关键词：

D O I：

10.1016/S0040-4039(97)00108-1

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Aldol-like reactions of titanium enolates derived from alpha-OH, alpha-OBn, and alpha-OTBS ketones with a series of aldehydes have been studied. In sharp contrast to the O-benzyl derivatives, the TBS-protected ketones lead to excellent yields and selectivities (syn-syn/anti-syn ratios from 30:1 to > 95:1) even for the lactate-derived substrate (2-tert-butyldimethylsilyloxy-3-pentanone). (C) 1997 Elsevier Science Ltd.

引用

页码：1637 / 1640

页数：4

共 21 条

[1]

[Anonymous], COMPREHENSIVE ORGANI

[2] ORIGINS OF STEREOSELECTIVITY IN CHIRAL BORON ENOLATE ALDOL REACTIONS - A COMPUTATIONAL STUDY USING TRANSITION-STATE MODELING [J].

BERNARDI, A ;

CAPELLI, AM ;

COMOTTI, A ;

GENNARI, C ;

GARDNER, M ;

GOODMAN, JM ;

PATERSON, I .

TETRAHEDRON, 1991, 47 (20-21) :3471-3484

[3] ALPHA'-BENZOYLOXY AND ALPHA'-METHOXYMETHOXY LITHIUM ENOLATES GIVING OPPOSITE DIASTEREOFACIAL SELECTIVITIES IN ALDOL REACTIONS - USE OF (PROBABLE) EXTENDED CHELATION FOR REVERSAL OF STEREOSELECTIVITIES [J].

CHOUDHURY, A ;

THORNTON, ER .

TETRAHEDRON LETTERS, 1993, 34 (14) :2221-2224

[4] Double stereodifferentiating aldol reactions of (E) and (Z) lithium enolates, model reactions for polypropionate assemblage [J].

Evans, DA ;

Yang, MG ;

Dart, MJ ;

Duffy, JL .

TETRAHEDRON LETTERS, 1996, 37 (12) :1957-1960

[5] STEREOSELECTIVE ALDOL REACTIONS OF CHLOROTITANIUM ENOLATES - AN EFFICIENT METHOD FOR THE ASSEMBLAGE OF POLYPROPIONATE-RELATED SYNTHONS [J].

EVANS, DA ;

RIEGER, DL ;

BILODEAU, MT ;

URPI, F .

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1991, 113 (03) :1047-1049

[6]

EVANS DA, 1995, J AM CHEM SOC, V117, P9074

[7]

Franklin A. S., 1994, CONTEMP ORG SYNTH, V1, P317

[8]

Gennari C., 1991, COMPREHENSIVE ORGANI, V2, P629, DOI DOI 10.1016/B978-0-08-052349-1.00043-3

[9] THE EFFECT OF PROTECTING GROUPS ON CHELATION CONTROL [J].

KAHN, SD ;

KECK, GE ;

HEHRE, WJ .

TETRAHEDRON LETTERS, 1987, 28 (03) :279-280

[10]

Kim B. M., 1991, COMPREHENSIVE ORGANI, V2, P239, DOI DOI 10.1016/B978-0-08-052349-1.00029-9

← 1 2 3 →