Highly enantioselective syntheses of anti homoaldol products by (-)-sparteine-mediated lithiation/transmetalation/substitution of N-Boc allylic amines

被引：25

作者：

Whisler, MC ^{[1
]}

Vaillancourt, L ^{[1
]}

Beak, P ^{[1
]}

机构：

[1] Univ Illinois, Dept Chem, Urbana, IL 61801 USA

来源：

ORGANIC LETTERS | 2000年 / 2卷 / 17期

关键词：

D O I：

10.1021/ol006186o

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

[GRAPHICS] (-)-Sparteine-mediated lithiation/transmetalation/substitution of N-Boc allylic amines provides anti-configured homoaldol precursors in yields of 38-85% and enantiomeric ratios of 83:17-99:1. Subsequent O-protection and hydrolysis allows access to O-protected homoaldol adducts in good yields. The absolute configurations of the homoaldol products have been assigned by calculation of optical rotations and by X-ray crystallography of derivatives. A stereochemical course of reaction for the lithiation/transmetalation/substitution sequence is proposed.

引用

页码：2655 / 2658

页数：4

共 22 条

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[2]

BASHA A, 1977, TETRAHEDRON LETT, V48, P4171

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