Platinum-catalyzed intramolecular hydroamination of unactivated olefins with secondary alkylamines

Abstract

Reaction of benzyl-2,2-diphenyl-4-pentenylamine with a catalytic 1:2 mixture of [PtCl2(H2C=CH2)]2 (2.5 mol %) and PPh3 in dioxane at 120 degrees C for 16 h led to isolation of 1-benzyl-2-methyl-4,4-diphenylpyrrolidine in 75% yield. A number of gamma- and delta-amino olefins underwent intramolecular hydroamination to form the corresponding pyrrolidine derivatives in moderate to good yield. The reaction displayed excellent functional group compatibility and low moisture sensitivity.