Synfacts 2011(5): 0525-0525  
DOI: 10.1055/s-0030-1259827
Metal-Catalyzed Asymmetric Synthesis and Stereoselective Reactions
© Georg Thieme Verlag Stuttgart ˙ New York

Enantioselective Cyclopropenation of Alkynes

Contributor(s): Mark Lautens, Hasnain A. Malik
X. Cui, X. Xu, H. Lu, S. Zhu, L. Wojtas, X. P. Zhang*
University of South Florida, Tampa, USA
Further Information

Publication History

Publication Date:
15 April 2011 (online)

Significance

Chiral cyclopropenes are highly strained carbocyclic compounds with unique properties that make them desirable synthons for a variety of synthetic transformations. The authors report a chiral metalloradical catalyst for a highly enantioselective cyclopropenation of terminal conjugated alkynes (specifically terminal aromatic or 1,3-enynes) using α-cyanodiazoacetamides and α-cyanodiazoacetates. The authors comment on the radical nature of the reaction mechanism based on the reactivity profile and the chemo­selectivity observed.