Chemically Modifiedβ-Cyclodextrins as Supramolecular Carriers in the Biphasic Palladium-Catalyzed Cleavage of Allylic Carbonates: Activity Enhancement and Substrate-Selective Catalysis

Abstract

Catalytic amounts of chemically modified β-cyclodextrins allowed us to achieve, in high yields, the deprotection of various water-insoluble allylic carbonates in a genuine two-phase system without co-solvent. The catalytic activities were up to 300 times higher than those observed without modified cyclodextrins. The process of molecular recognition between the cyclodextrin and the substrate allowed us to perform substrate-selective catalytic reactions which cannot be achieved in homogeneous or biphasic media with conventional transition metal catalysts.