Polyketide synthesis using the boron-mediated, anti-aldol reactions of lactate-derived ketones:: Total synthesis of (-)-ACRL, toxin IIIB

被引：143

作者：

Paterson, I ^{[1
]}

Wallace, DJ ^{[1
]}

Cowden, CJ ^{[1
]}

机构：

[1] Univ Cambridge, Chem Lab, Cambridge CB2 1EW, England

来源：

SYNTHESIS-STUTTGART | 1998年

关键词：

chiral auxiliary; lactate; enol borinate; anti-aldol; (-)-ACRL toxin IIIB;

D O I：

10.1055/s-1998-5929

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The boron-mediated, anti-selective, aldol reactions of ketone 2 (and related derivatives) proceed with high levels of asymmetric induction, diastereoselectivities of up to 200:1 in favour of the aldol adducts 4 are obtained with achiral aldehydes and reagent control operates with chiral aldehydes. These lactate-derived ketones provide a versatile chiral auxiliary for the synthesis of beta-hydroxy carbonyl compounds. Oxidative removal of the auxiliary provides enantiomerically pure aldehydes 5, while reductive deoxygenation gives the corresponding ethyl ketones 6. This practical asymmetric methodology for generating anti-aldols is illustrated by an efficient total synthesis of (-)-ACRL toxin IIIB (7), which proceeds in 15 steps from 2 with 21% overall yield and 88% diastereoselectivity.

引用

页码：639 / 652

页数：14

共 59 条

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