Synthesis of the C20-C32 Tetrahydropyran Core of the Phorboxazoles and the C22 Epimer via a Stereodivergent Michael Reaction

被引：13

作者：

Clarke, Paul A. ^{[1
]}

Ermanis, Kristaps ^{[1
]}

机构：

[1] Univ York, Dept Chem, York YO10 5DD, N Yorkshire, England

来源：

ORGANIC LETTERS | 2012年 / 14卷 / 21期

基金：

英国工程与自然科学研究理事会;

关键词：

2ND-GENERATION TOTAL-SYNTHESIS; STEREOSELECTIVE-SYNTHESIS; ASYMMETRIC-SYNTHESIS; CONVERGENT; PRODUCTS; FRAGMENT; AGENT; POT;

D O I：

10.1021/ol3026523

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

A stereoselective synthesis of the C20-C32 tetrahydropyran core of the phorboxazoles has been achieved in only seven steps and in a 31% overall yield. The C22 epimer was also synthesized. The key step was a silyl ether deprotection/oxy-Michael cyclization. When this step was conducted under Bronsted acid conditions, the C20-C32 core was formed with the desired 2,6-cis-stereochemistry. However, when the silyl ether deprotection/oxy-Michael cyclization was conducted under fluoride conditions buffered with acetic acid, the C22 epimer of the core was the sole product.

引用

页码：5550 / 5553

页数：4

共 48 条

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