A palladium-catalyzed enantioselective [4 + 2] cycloaddition reaction of vinyl benzoxazinones with sulfamate-derived cyclic imines is described, affording the tetrahydroquinazolines bearing several functional rings in high yields (up to 99% yield) with good to excellent diastereoselectivities and excellent enantioselectivities (up to 96% ee). This reaction represents the first Pd-catalyzed asymmetric decarboxylative cycloaddition of vinyl benzoxazinones with imines.

Herein we describe the first organocatalytic asymmetric C(sp2)−H allylation of racemic trisubstituted allenoates with Morita–Baylis–Hillman (MBH) carbonates to access axially chiral tetrasubstituted allenoates. Various trisubstituted allenoates and MBH carbonates were well tolerated under mild reaction conditions, providing novel chiral tetrasubstituted allenoates with adjacent axial chirality and tertiary carbon stereocenters in high yields with good to excellent diastereoselectivities and enantioselectivities.

A palladium‐catalyzed [4+2] cycloaddition of hydroxy‐tethered allyl carbonates with five types of electron‐deficient alkenes has been achieved, in which a type of new hydroxy‐tethered allyl carbonates acted as valuable precursors for the formation of 1,4‐C,O‐dipole allylpalladium intermediates. The reaction proceeded efficiently under mild reaction conditions to provide the corresponding tetrahydropyran derivatives in moderate to high yields with excellent diastereoselectivities.

The phosphine-catalyzed cascade Michael addition/[4+2] cycloaddition reaction of tetrahydrobenzofuranone-derived allenoates and 2-arylidene-1,3-indanediones has been reported, affording spirocyclic 1,3-indanedione derivatives in moderate to high yields with moderate to good diastereoselectivities. A scaled-up reaction worked well under mild conditions, and a plausible mechanism is proposed.

A phosphine-catalyzed [4 + 2] cycloaddition of cyclic α-substituted allenoates with sulfamate-derived cyclic imines has been reported. Using dibenzylphenylphosphine as the nucleophilic catalyst, the reaction worked efficiently to yield various fused multicyclic heterocyclic compounds in high yields with excellent diastereoselectivities. It undergoes a new reaction mode involving γ'-carbon of α-substituted allenoate.