THE CHEMISTRY OF ORGANOBORATES .9. A REGIOSPECIFIC AND HIGHLY STEREOSELECTIVE CONSTRUCTION OF TRISUBSTITUTED ALPHA-BETA-UNSATURATED KETONES, TETRASUBSTITUTED ALPHA-BETA-UNSATURATED KETONES AND SPECIFICALLY PROTECTED 1,3-DIKETONES FROM ALKYNYLTRIALKYLBORATES

被引：12

作者：

PELTER, A

COLCLOUGH, ME

机构：

[1] Department of Chemistry, University of Wales, Swansea, Swansea, SA2 8PP, Singleton Park

来源：

TETRAHEDRON | 1995年 / 51卷 / 03期

关键词：

D O I：

10.1016/0040-4020(94)00953-R

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Lithium alkynyltrialkylborates react with dioxolanium fluorosulphonates in a highly stereoselective fashion such that the dioxolanium group and the migrating group are on the same side of the new alkene intermediate. Hydrolysis of the intermediate yields Z-trisubstituted alpha beta-unsaturated ketones in which all three substituents have different origins and can be independently varied. Oxidation of the intermediates gives beta-ketoacetals, which are regiospecifically protected 1,3-diketones. If the initial intermediates are allowed to stand, then another migration occurs and tetra-substituted alpha beta-unsaturated ketones result.

引用

页码：811 / 828

页数：18

共 40 条

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