Enantioselective alkynylation to aldimines catalyzed by chiral 2,2′-di(2-aminoaryloxy)-1,1′-binaphthyl-copper(I) complexes
作者:Manabu Hatano、Takafumi Asai、Kazuaki Ishihara
DOI:10.1016/j.tetlet.2007.11.032
日期:2008.1
The enantioselective alkynylation of aldimines with terminal acetylenes catalyzed by chiral Cu(I) complexes with (R)-2,2'-di(2-aminoaryloxy)-1,1'-binaphthyl ligands (7) was examined. Chiral C-2-symmetric N,N-ligands 7, which have primary aniline moieties, were readily prepared from inexpensive (R)-1,1'-binaphthol (BINOL) as a chiral source. In particular, the reaction of N-benzylidenebenzeneamine 1a with phenylacetylene 2a proceeded smoothly in the presence of 5 mol% of (CuOTf)(2)center dot C6H5CH3 and 10 mol% of (R)-7d at room temperature for 24 h, and the corresponding propargylamine 3a was obtained with up to 82% ee. (C) 2007 Elsevier Ltd. All rights reserved.