| Abstract
| - Several Rh(I), Ir(III), and Pt(II) complexes of thechiral P,S-bidentate ligand 2 have beenprepared and characterized. Detailed two-dimensional NMR studiesshow that (i) the boat-type chelate ring and the stereogenic sulfur center can invert rapidlyat ambient temperatureand (ii) the sulfur donor may dissociate, essentially destroying thechiral pocket. The solid-state structure of[Pt(η3-C3H5)(2)]PF6(3) has been determined and the sulfursubstituentshown to have an axial orientation. The six-membered chelate ringtakes up a boatlikeconformation. As shown by an X-ray diffraction study for3, and via incoherent inelasticneutron scattering (IINS) measurements for the Pd analog, 4,the OH group is remote fromthe metal atom.
- 2-D exchange NMR experimentsshow that the chiral exo-norborneol-based P,S-thioether ligand isconformationally mobile in both square-planar and octahedralenvironments, such that one cannot speak of a rigid chiral pocket.There are indications that this ligand may dissociate the sulfurdonor. X-ray and inelastic neutron scattering results show thatthe OH group is not involved in bonding to the metal in allyl complexesof Pd(II) and Pt(II).
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