Synthesis and stereochemical studies of η3-allyl palladium(II) complexes containing a chiral chelating ligand

Abstract

A complex of the type [Pd(η³-CH₂CMeCH₂)(P–P′)]⁺[where P–P′= the chiral chelating ligand (S-)–(N-diphenylphosphino)(2-diphenylphosphinoxymethyl) pyrrolidine, not having C_2v symmetry] has been prepared and its ¹H, ¹³C, ³¹P, and two-dimensional H–X (X =¹³C or ³¹P) correlation spectra recorded. On the basis of n.m.r. data the absolute configurations in solution of the major and minor diastereoisomers have been assigned. Proton and ¹³C n.m.r. data have been discussed in terms of trans influence of the chelating ligand P–P′. Correlations between the n.m.r. parameters of the intermediate η³-allyl diastereoisomers, donor properties of the ligand, and regiochemistry of nucleophilic addition to the allyl termini have been proposed.