Synfacts 2006(1): 0048-0048  
DOI: 10.1055/s-2005-921680
Metal-Catalyzed Asymmetric Synthesis and Stereoselective Reactions
© Georg Thieme Verlag Stuttgart · New York

Enantioselective [2+2+2] Cycloaddition of 1,6-Enynes and Alkynes

Contributor(s): Mark Lautens, Josephine Yuen
T. Shibata*, Y. Arai, Y-K. Tahara
Waseda University, Tokyo, Japan
Further Information

Publication History

Publication Date:
16 December 2005 (online)

Significance

Enantioselective [2+2+2] cycloaddition of 1,6-enynes and alkynes using chiral rhodium catalysts gave cycloadducts containing a chiral quaternary center. In all cases, the enantio­selectivity was high and yields were moderate to good. A range of alkynes was tolerated, including acetylene and also an unprotected diol. Use of unsymmetrical alkynes resulted in a mixture of regioisomers (4:1 to 7:1). O, N and C-bridged enynes were also applied to the reaction.