Asymmetric Synthesis of N‐Fused 1,3‐Oxazolidines via Pd‐Catalyzed Decarboxylative (3+2) Cycloaddition
Jong‐Un Park, Hye‐In Ahn, Ho‐Jun Cho, Zi Xuan, Ju Hyun Kim
Abstract
Abstract Efficient synthesis of optically active N‐fused 1,3‐oxazolidines containing quaternary and tertiary stereocenters was achieved via Pd‐catalyzed asymmetric (3+2) cycloadditions of sulfamate‐derived cyclic imines and vinylethylene carbonates. Using a chiral phosphoramidite ligand, the cycloadditions proceeded effectively providing sulfamidate‐fused 1,3‐oxazolidines in high yields (up to 96%) with stereoselectivities (up to 25:1 dr; >99% ee). Additionally, the scale‐up reaction and further transformations of the product were also achieved demonstrating the synthetic utility toward the construction of useful heterocycles such as chiral oxazoline bearing a quaternary stereocenter. magnified image