The Journal of Organic Chemistry

Synthesis of 12-, 14-, and 16-membered propargylic alcohols through Lewis acid-promoted ene cyclization

JA Marshall, MW Andersen

Index: Marshall, James A.; Andersen, Marc W. Journal of Organic Chemistry, 1993 , vol. 58, # 15 p. 3912 - 3918

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Citation Number: 25

Abstract

The scope of the Lewis acid-promoted ene cyclization has been expanded to include 12-, 14- , and 16-membered rings. Thus, the pals 1.8, 2.5, and 3.5 undergo efficient type-I cyclization upon addition to 1.0 equiv of EtAlClz in CHzClz at-78" C. The epoxy yna14. 3 undergoes pinacol rearrangement under these conditions. However, treatment with a 1: l mixture of EhAlCl and EtAlC12 effects conversion to the cyclic products 4.4/4.5 (92: 8) in satisfactory ...