First asymmetric nucleophilic displacement reactions on chiral α-substituted aldehyde hydrazones

被引：7

作者：

Enders, D ^{[1
]}

Maassen, R ^{[1
]}

Runsink, J ^{[1
]}

机构：

[1] Rhein Westfal TH Aachen, Inst Organ Chem, D-52074 Aachen, Germany

来源：

TETRAHEDRON-ASYMMETRY | 1998年 / 9卷 / 12期

关键词：

D O I：

10.1016/S0957-4166(98)00205-5

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The first asymmetric nucleophilic substitution reaction on racemic alpha-substituted aldehydes using enantiomerically pure hydrazines as chiral auxiliaries is presented. The diastereoselectivity of the process is achieved by a dynamic kinetic resolution via the 1:1 epimeric mixture of the substrate hydrazones. The a(2)-reactivity (Umpolung) of the alpha-substituted hydrazones is accomplished by complexation with Lewis acids. Several carbon-, sulfur- and oxygen-nucleophiles were shown to readily undergo substitution of the alpha-leaving group under these conditions, affording the substitution products with good to excellent chemical yields and with low to moderate diastereoselectivities. Two methods for the cleavage of the chiral auxiliary are described. (C) 1998 Eisevier Science Ltd. All rights reserved.

引用

页码：2155 / 2180

页数：26

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