Unexpected photoisomerization of a pincer-type amido ligand leads to facial coordination at Pt(IV).
The divalent complex (BQA)PtMe undergoes oxidative addition with MeI to afford the octahedral complex cis-(mer-BQA)PtMe2I {(BQA)- = bis(8-quinolinyl)amide}. When this molecule is irradiated with visible light, it isomerizes to (fac-BQA)PtMe2I, where the BQA ligand adopts an unexpected facial coordination mode. The amide nitrogen in this molecule is sp3 hybridized and can be easily quarternized with HBF4, resulting in [H(fac-BQA)PtMe2I][BF4], with only minor perturbation to the coordination sphere.
Harkins
Seth B
SB
Division of Chemistry and Chemical Engineering, Arnold and Mabel Beckman Laboratories of Chemical Synthesis, California Institute of Technology, Pasadena, California 91125, USA.
Peters
Jonas C
JC