Planar chiral [2.2]paracyclophane-based phosphine-Bronsted acid catalysts bearing exceptionally high reactivity for aza-Morita-Baylis-Hillman reaction

Several new planar chiral bifunctional phosphine compounds based on the [2.2]paracyclophane backbone with a pseudo-ortho substitution pattern have been synthesized and applied to the aza-Morita-Baylis-Hillman reaction. An enantiopure phosphine-phenol catalyst bearing an aryl group as a spacer connected to a phosphino group exhibited an exceptionally high reactivity (rt, 2-40 min) and good enantioselectivity (up to 85% ee). (C) 2012 Elsevier Ltd. All rights reserved.