Reactivity of chiral oxazaphospholidines on activated halide compounds: Synthesis and coordination studies of chiral hybrid phosphine-phosphine oxide ligands

The Michaelis Arbuzov reaction between the enantiopure 2-phenyl-1,3,2-oxazaphospholidine 1 and different activated halide compounds 2 afforded with total diastereoselectivity chiral phosphinamides 3. Oxazaphospholidine 1 reacted with alpha-haloacetophenones 4a-c to give both chiral Michaelis Arbuzov products 5 and a mixture of diastereomers 6:7 as the Perkow products. New hybrid phosphine-phosphine oxide ligands were easily obtained from phosphinamides 3, bearing chirality on the carbon chain and the phosphine oxide moiety (BPPO), or on the carbon chain and the two different phosphorus centers (8 and 9). The coordination chemistry of ligand BPPO has been studied with transition metals and Lewis Acids. (C) 1997 Elsevier Science Ltd.