Stereochemistry of formation and reactions of carbonyldichloro-(threo-α,β-dideuteriophenethyl)bis(triphenylphosphine)-rhodium and -iridium complexes

Abstract

Treatment of [RhCl(PPh₃)₃] and [IrCl(N₂)(PPh₃)₂] with threo-PhCHD·CHD·CO·Cl gives the complexes [(dpp)-MCl₂(PPh₃)₂](M = Rh or Ir; dpp =threo-2,3-deuterio-3-phenylpropionyl) and [(dpe)IrCl₂CO(PPh₃)₂](dpe =threo-α,β-dideuteriophenethyl); the alkyl migration reaction in this system thus proceeds with retention of configuration. Decomposition of both rhodium and iridium complexes yields all six possible mono- and di-deuteriostyrenes. The product distribution is interpreted in terms of a series of reversible β-elimination reactions.