Tetrahedron

Efficient stereodivergent synthesis of erythro-and threo-sphingosines: unprecedented reversal of the stereochemistry in the addition

T Murakami, K Furusawa

Index: Murakami, Teiichi; Furusawa, Kiyotaka Tetrahedron, 2002 , vol. 58, # 45 p. 9257 - 9263

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Citation Number: 47

Abstract

A convenient diastereoselective synthesis of d-erythro-and l-threo-sphingosine derivatives is described. l-Serine-derived aldehyde (Garner's aldehyde)(2) was treated with 1-alkenyl- zirconocene chlorides (3) in the presence of ZnBr2 in THF to give the natural erythro-(anti-) isomers with high diastereoselectivity (anti/syn= 12–20: 1). In contrast, reaction of 2 with 1- alkenyl-ethyl-zinc, prepared from 3 and Et2Zn, in CH2Cl2 gave the unnatural threo-(syn-) ...