Supported Group II Transition Metal Catalysts in Liquid Phase Reactions using Borrowing Hydrogen Methodology

Abstract

The borrowing hydrogen methodology is an interesting protocol for the activation of alcohols and amines, which starts with the abstraction of hydrogen from the starting R1-XH (X = O, NH,) by a catalyst forming unsaturated R1=X condensing with R2 to form an unsaturated intermediate. The abstracted hydrogen is then returned and hydrogenates intermediate to generate the final product. It is ?green? and highly atom efficient. In this thesis, supported Ag was developed showing activity for the oxidative dehydrogenation of alcohols, with good selectivity to the corresponding aldehyde or ketone. This hydride removal is the crucial step in the activation of alcohols for subsequent coupling with suitable nucleophiles. Later, supported group 11 metals mainly Cu and Ag were prepared and their activities were tested in the N-alkylation of amines by alcohols, reductive N-alkylation of nitroarenes by alcohols, and self-coupling of aromatic amines, in all cases using the borrowing hydrogen methodology.