Transition metal halide promoted hydride transfer in N,N-diisoalkyl-N-propargylamines

The reaction of N,N-diisopropyl-N-propargylamines with Et₃Al/MX_n system (MX_n=CuCl, CuBr, ZnCl₂, ZnI₂, CdI₂, TiCl₄, ZrCl₄, VCl₅, TaCl₅) in CH₂Cl₂ proceeds as an intramolecular red-ox hydride transfer affording N-dealkylated N-isopropyl-N-allylamines, allenes being formed as side products. The highest chemoselectivities and yields (71–89%) were attained by the application of new ZnI₂/(MeAlO)_n system.