NMR-STUDIES OF CHIRAL P,S-CHELATE PLATINUM, RHODIUM, AND IRIDIUM COMPLEXES AND THE X-RAY STRUCTURE OF A PALLADIUM(II) ALLYL DERIVATIVE

Several Rh(I), Ir(III), and Pt(II) complexes of the chiral P,S-bidenta te ligand 2 have been prepared and characterized. Detailed two-dimensi onal NMR studies show that (i) the boat-type chelate ring and the ster eogenic sulfur center can invert rapidly at ambient temperature and (i i) the sulfur donor may dissociate, essentially destroying the chiral pocket. The solid-state structure of [Pt(eta(3)-C3H5)(2)]PF6 (3) has b een determined and the sulfur substituent shown to have an axial orien tation. The six-membered chelate ring takes up a boatlike conformation . As shown by an X-ray diffraction study for 3, and via incoherent ine lastic neutron scattering (IINS) measurements for the Pd analog, 4, th e OH group is remote from the metal atom.