Ligand-based reactivity of a platinum bisdithiolene: double diene addition yields a new C2-chiral chelate ligand.
The reaction of Pt(tfd)(2) [tfd = S(2)C(2)(CF(3))(2)] with excess 2,3-dimethyl-1,3-butadiene initially yields the expected 1:1 adduct, in which the diene has added across two sulfur atoms on separate tfd ligands. However, within 1 day at 50 degrees C, this kinetic product quantitatively converts into a thermodynamic product where two dienes have added to one tfd ligand via unprecedented addition across the dithiolene CS bonds. The new reaction is highly selective for the C(2)-symmetric diastereomer. A new chiral bisthioether chelate ligand has formed in the product, which has been characterized crystallographically.
Kerr
Mitchell J
MJ
University of Toronto Mississauga, 3359 Mississauga Road N, Mississauga, Ontario, Canada L5L 1C6.
Harrison
Daniel J
DJ
Lough
Alan J
AJ
Fekl
Ulrich
U