SYNTHESIS OF 12-MEMBERED, 14-MEMBERED, AND 16-MEMBERED PROPARGYLIC ALCOHOLS THROUGH LEWIS ACID-PROMOTED ENE CYCLIZATION

被引：24

作者：

MARSHALL, JA

ANDERSEN, MW

机构：

[1] Department of Chemistry and Biochemistry, University of South Carolina, Columbia

来源：

JOURNAL OF ORGANIC CHEMISTRY | 1993年 / 58卷 / 15期

关键词：

D O I：

10.1021/jo00067a024

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The scope of the Lewis acid-promoted ene cyclization has been expanded to include 12-, 14-, and 16-membered rings. Thus, the ynals 1.8, 2.5, and 3.5 undergo efficient type-I cyclization upon addition to 1.0 equiv of EtAlCl2 in CH2Cl2 at -78-degrees-C. The epoxy ynal 4.3 undergoes pinacol rearrangement under these conditions. However, treatment with a 1:1 mixture of Et2AlCl and EtAlCl2 effects conversion to the cyclic products 4.4/4.5 (92:8) in satisfactory yield. Facile type-II cyclizations readily achieved with ynals 5.7, 6.4, 7.6, and 8.3 with EtAlCl2 as the Lewis acid. In the latter case, a 16-membered propargylic alcohol was produced in 84% yield.

引用

页码：3912 / 3918

页数：7

共 29 条

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