Catalytic isomerization of 1,5-enynes to bicyclo[3.1.0]hexenes

Michael R Luzung; Jordan P Markham; F Dean Toste

doi:10.1021/ja046248w

Catalytic isomerization of 1,5-enynes to bicyclo[3.1.0]hexenes

J Am Chem Soc. 2004 Sep 8;126(35):10858-9. doi: 10.1021/ja046248w.

Authors

Michael R Luzung¹, Jordan P Markham, F Dean Toste

Affiliation

¹ Center for New Directions in Organic Synthesis, Department of Chemistry, University of California-Berkeley, Berkeley, CA 94720, USA.

PMID: 15339167
DOI: 10.1021/ja046248w

Abstract

The cycloisomerization of 1,5-enynes catalyzed by cationic triphenylphosphinegold(I) complexes produces bicyclo[3.1.0]hexenes. Substitution at all positions of the 1,5-enyne is tolerated, leading to a wide range of bicyclo[3.1.0]hexane structures, including those containing quaternary carbons. Substrates containing a 1,2-disubstituted olefin undergo stereospecific cycloisomerization (cis-olefin produces cis-cyclopropane, and trans-olefin gives trans-cyclopropane). Additionally, enantioenriched bicyclo[3.1.0]hexenes can be obtained from the gold(I)-catalyzed cycloisomerization of enantioenriched 1,5-enynes with excellent chirality transfer. The preparation of tricyclic systems is accomplished through a gold(I)-catalyzed tandem cycloisomerization-ring enlargement reaction.