The application of monoterpene derived chiral PHOX ligands in Tsuji-Trost reaction

The Tsuji-Trost reaction is palladium-catalyzed substitution using nucleophile with a substrate containing a leaving group in an allylic position. This reaction can be used for the formation of the carbon-carbon, carbon-nitrogen, and carbon-oxygen new bonds by applying appropriate nucleophiles such as active methylenes, enolates, amines, and phenols. The leaving group can be for example acetate, carbonate or a halide.

Herein, we present the synthesis of PHOX ligands from amino alcohols derived from α-pinene and β-pinene. The resulting oxazolines were used as chiral ligands in palladium catalyzed asymmetric allylic substitution reaction. We studied the influence of the leaving group in a substrate and the type of nucleophile for enantioselectivity of the reaction.