Enabling Ligand Screening for Palladium-Catalysed Enantioselective Aza-Michael Addition Reactions
作者:Pim Huat Phua、Andrew J. P. White、Johannes G. de Vries、King Kuok (Mimi) Hii
DOI:10.1002/adsc.200505404
日期:2006.3
palladium(II) precursor for the generation of dicationic palladium(II) catalysts. Parallel ligandscreening is enabled for the first time, and twenty-four chiral ligands were evaluated for the asymmetric aza-Michaeladdition of aromatic amines to α,β-unsaturated N-alkenoylimides and carbamates. Enantioselectivities of >99% can be obtained. Catalytic precursors generated from 1 using the new protocol have