Download PDF
Synfacts 2010(1): 0025-0025  
DOI: 10.1055/s-0029-1218459
Synthesis of Heterocycles
© Georg Thieme Verlag Stuttgart ˙ New York

Rhodium-Catalyzed Synthesis of Pyrroles by [4+1] Cycloaddition

Contributor(s): Victor Snieckus, Emilie David
A. Mizuno, H. Kusama, N. Iwasawa*
Tokyo Institute of Technology, Japan
Further Information

Publication History

Publication Date:
21 December 2009 (online)

    Permissions and Reprints

Significance

Iwasawa and co-workers report the rhodium(I)-catalyzed [4+1] cycloaddition of α,β-unsaturated imines with terminal alkynes to afford pyrrole derivatives. The best results were obtained using [{RhCl(coe)2}2] as catalyst and Cy3P as ligand. A mechanism involving nucleophilic addition of the imine nitrogen to the carbene carbon of the rhodium vinylidene complex A is proposed. In support of this mechanism, the isolated vinylidene complex {RhCl[=C=C(H)n-Hex](PCy3)2} also catalyzed the reaction under similar conditions. Further mechanistic studies have been promised.