Platinum-Catalyzed Intramolecular Hydroamination of Unactivated Olefins with Secondary Alkylamines

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 °C for 16 h led to isolation of 1-benzyl-2-methyl-4,4-diphenylpyrrolidine in 75% yield. A number of γ- and δ-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.