Trimethylplatinum(IV) complexes of dithiocarbamato ligands: an experimental NMR study on the barrier to C-N bond rotation.
J CHEM SOC DALTON
1349 - 1356.
The trimethylplatinum(IV) complexes of a number of dithiocarbamato ligands have been prepared. The complexes are dimeric in the solid state and in solution, with the ligands acting in both a bridging and chelating fashion. Restricted rotation about the ligand C-N bonds in solution leads to the formation of four rotomers. The kinetics of the restricted rotation was measured by a variety of dynamic NMR techniques in the slow and intermediate exchange regimes. Two distinct processes are observed, namely the independent rotation about each C-N bond and correlated rotation about both C-N bonds. The free energies of activation, which are strongly dependent on the nature of the ligand substituents, are in the range 65-88 kJ mol(-1) at 298 K. The origins of the barrier to rotation and the effects of the nitrogen substituents are discussed. The crystal structures of fac-[PtMe3(Me2NCS2)](2) and fac-[PtMe3(Ph(H)NCS2)](2) are reported.
|Title:||Trimethylplatinum(IV) complexes of dithiocarbamato ligands: an experimental NMR study on the barrier to C-N bond rotation|
|Keywords:||CHEMICAL-EXCHANGE, AMIDE RESONANCE, THIOFORMAMIDE, SYSTEMS, ORIGIN|
|UCL classification:||UCL > School of BEAMS
UCL > School of BEAMS > Faculty of Maths and Physical Sciences
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