RING-ENLARGING ANNULATIONS - A ONE-STEP CONVERSION OF CYCLIC SILYL ACYLOINS AND OMEGA-ALKYNYL ACETALS TO POLYCYCLIC ENEDIONES

被引：39

作者：

BALOG, A ^{[1
]}

CURRAN, DP ^{[1
]}

机构：

[1] UNIV PITTSBURGH,DEPT CHEM,PITTSBURGH,PA 15260

来源：

JOURNAL OF ORGANIC CHEMISTRY | 1995年 / 60卷 / 02期

关键词：

D O I：

10.1021/jo00107a011

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

new sequence of cationic reactions that converts cyclic silyl acyloins and omega-alkynyl acetals to polycyclic enediones is reported. For example, treatment of bis-1,2-((trimethylsilyl)oxy)cyclobutene and 2-(ethylenedioxy)-5-heptyne with excess boron trifluoride etherate in methylene chloride for 2 days provides 4-acetyl-3,5,6,6a-tetrahydro-6a-methyl-1-(2H)-pentalenone in 58% yield. This product is formed via a sequence involving a Mukaiyama aldol reaction, a pinacol ring expansion, and a 5-exo-dig alkynyl ketone cyclization. In the case of terminal alkynes, the last cyclization occurs in a 6-endo-dig fashion. The scope and limitations of this process are studied, and a number of bi- and tricyclic ring systems are formed.

引用

页码：337 / 344

页数：8

共 40 条

[1]

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