structured aliphaticketones and electron‐deficient cyclic 1‐azadienes was developed by cascade enamine–enamine catalysis of a cinchona‐based primary amine. This sequence involved a domino Michael addition–Mannich reaction to afford spirocyclic architectures in excellent diastereo‐ and enantioselectivity. Importantly, high regioselectivity was realized for a number of unsymmetrical aliphaticketone substrates
Chiral Phosphine-Catalyzed Enantioselective [3+2] Annulation of Morita-Baylis-Hillman Carbonates with Cyclic 1-Azadienes: Synthesis of Functionalized Cyclopentenes
catalyst, the asymmetric [3+2] annulation of Morita–Baylis–Hillman carbonates with cyclic 1‐azadienes proceeded smoothly under mild conditions to give various enantiomerically enriched cyclopentene derivatives bearing three consecutive tertiary stereocenters and a sulfamate moiety in moderate to excellent yields with moderate to excellent enantioselectivities and excellent diastereoselectivities.
palladium-catalyzed [3 + 2] cycloaddition of vinylcyclopropanes and 1-azadienes has been developed under mild reaction conditions, giving the multisubstituted cyclopentane derivatives in good to excellent yields with moderate to good diastereoselectivities. The relative configuration of both diastereomers of the products have been determined through X-raycrystallographic diffraction.