A resolution of the monodentate P*-chiral phosphine PBu(t)C6H4Br-4 and itsNMR-deduced absolute configuration

Both enantiomers of the monodentate phosphine (PBuC6H4Br)-C-t-4 were obtain ed in an enantiopure state by chromatographic separation of their diastereo meric adducts with a new homochiral ortho-palladated resolving agent derive d from alpha-tert-Bu-substituted tertiary benzylamine. The conformation of the palladacycle and the absolute configuration of the phosphine were deter mined using TH NMR spectroscopy (including NOE technique) and confirmed by an X-ray diffraction study of both diastereomeric complexes. The enantiomer s of the resolved phosphine were displaced from the individual diastereomer s of the palladium(II) complexes with recovery of the starting resolving ag ent, and trapped in the form of binuclear coordination complexes of palladi um(II). (C) 1999 Published by Elsevier Science Ltd. All rights reserved.