Asymmetric nucleophilic catalysis with planar-chiral DMAP derivatives and chiral phosphines : synthetic and mechanistic studies

Abstract

Chapter 1 describes the development and detailed mechanistic investigation of the first non-enzymatic method for the dynamic kinetic resolution of secondary alcohols via enantioselective acylation, with acetyl isopropyl carbonate, through the use of a planar-chiral DMAP derivative (an acylation catalyst) in combination with a ruthenium complex (an alcohol-racemization catalyst). Chapter 2 describes the development and detailed mechanistic investigation of the enantioselective synthesis of tertiary alkyl fluorides via the [alpha]-fluorination of ketenes catalyzed by a planar-chiral nucleophile with N-fluorodibenzenesulfonimide in the presence of sodium pentafluorophenoxide. Chapter 3 describes the development and preliminary mechanistic study of the first asymmetric, phosphine-catalyzed intramolecular [3 + 2] cycloadditions of allenes with alkenes that furnish an array of diastereomerically pure bicyclic compounds bearing two or three contiguous tertiary! quaternary stereocenters.