LEWIS-ACID-MEDIATED AND CATIONIC LITHIUM-MEDIATED DIASTEREOSELECTIVE ALDOL-TYPE REACTION-BASED ON A DOUBLE CHIRAL RECOGNITION MANNER FOR THE ASYMMETRIC-SYNTHESIS OF ALPHA-SUBSTITUTED SERINES

被引：27

作者：

SANO, S

LIU, XK

TAKEBAYASHI, M

KOBAYASHI, Y

TABATA, K

SHIRO, M

NAGAO, Y

机构：

[1] UNIV TOKUSHIMA,FAC PHARMACEUT SCI,TOKUSHIMA 770,JAPAN

[2] RIGAKU CORP,AKISHIMA,TOKYO 196,JAPAN

来源：

TETRAHEDRON LETTERS | 1995年 / 36卷 / 23期

关键词：

D O I：

10.1016/0040-4039(95)00725-R

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Diastereoselective aldol-type reaction of ethyl (5R or 5S)-3,6-diethoxy-2,5-dihydro-5-isopropyl-2-pyrazinecarboxylate (5) with chiral aldehyde 7 was investigated by using Sn(OSO2CF3)(2)-N-ethylpiperizine, MgBr2-Et(3)N, n-butyllithium, and lithium diisopropylamide. The mediation mode with Sn(II) between (5R or 5S)-5 and 7 proved to be quite different from that with Mg(II). The two aldol products were converted to the corresponding gamma-lactonic alpha-substituted serines (2S)- and (2R)-10.

引用

页码：4101 / 4104

页数：4

共 12 条

[1]

Anh N. T., 1980, TOP CURR CHEM, V88, P145

[2] ORIGIN OF PI-FACIAL STEREOSELECTIVITY IN ADDITIONS TO PI-BONDS - GENERALITY OF THE ANTI-PERIPLANAR EFFECT [J].