Synfacts 2007(7): 0713-0713  
DOI: 10.1055/s-2007-968621
Metal-Catalyzed Asymmetric Synthesis and Stereoselective Reactions
© Georg Thieme Verlag Stuttgart · New York

Copper-Catalyzed Enantioselective N-H Insertion Reactions

Contributor(s): Mark Lautens, Praew Thansandote
B. Liu, S.-F. Zhu, W. Zhang, C. Chen, Q.-L. Zhou*
Nakai University, Tianjin, P. R. of China
Further Information

Publication History

Publication Date:
22 June 2007 (online)

Significance

A highly enantioselective catalytic insertion of α-diazoesters into N-H bonds is reported. The catalyst is prepared from a Cu(I) source, a spiro-bisoxazoline ligand, and a BARF counterion. A wide range of substituted anilines and naphthalenamines could be used for the insertion reaction with complete conversions observed within two hours and high yields and enantio­selectivities were obtained. However, an electron-donating group in the para position of a phenyl-substituted aniline or a halogen at the ortho position resulted in slightly lower enantioselectivities for unknown reasons. The ester group on the diazoester could be changed with negligible effect; however, the diazo substituent is more sensitive and can lead to lower yields or ee values. No enantioselectivity was induced with N-meth­ylaniline and benzamide, and cyclohexylamine was inert under the reported conditions.