Synthesis 2007(16): 2539-2544  
DOI: 10.1055/s-2007-983804
SPECIALTOPIC
© Georg Thieme Verlag Stuttgart · New York

Bulky Thioureas as New Ligands for Gold(I)-Catalyzed Cyclization of Acetylenic 1,3-Dicarbonyl Compounds

Jie-Hui Pan, Min Yang, Qiang Gao, Nian-Yong Zhu, Dan Yang*
Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. of China
e-Mail: yangdan@hku.hk;
Further Information

Publication History

Received 5 May 2007
Publication Date:
24 July 2007 (online)

Abstract

We illustrate the first use of bulky N,N′-disubstituted cyclic thioureas as ligands for gold(I) catalysis. X-ray crystal structures of the thiourea-gold(I) complexes presented important information about the nature of the complexation. These complexes were found to be active catalysts for the cyclization of 1,3-dicarbonyl compounds with alkynes (Conia-ene reaction). Various acetylenic 1,3-dicarbonyl compounds underwent cycloisomerization to give mono- and bicyclic olefinic cyclopentanes in the presence of one mol% of a thiourea-gold(I) chloride complex and silver triflate.