Synlett 2011(8): 1109-1112  
DOI: 10.1055/s-0030-1259931
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

Exploiting Guanidine as a Ligand in Cobalt-Catalyzed Alkyne Cyclotrimerizations

Chad C. Eichman, Jason P. Bragdon, James P. Stambuli*
Evans Chemical Laboratories, The Ohio State University, 100 West 18th Avenue, Columbus, OH 43210, USA
e-Mail: stambuli@chemistry.ohio-state.edu;
Further Information

Publication History

Received 19 February 2011
Publication Date:
30 March 2011 (online)

Abstract

The synthesis of polysubstituted arenes is accomplished via the regioselective cyclotrimerization of alkynes utilizing a guanidine-ligated cobalt catalyst.

19

This result further demonstrates the effect of the guanidine ligand on the reaction outcome by providing higher regio-selectivities compared to the ‘ligandless’ system (see results in ref. 11d).