SELF-ASSEMBLY OF A COMPLEX FLUORINATED METALLACYCLE FROM HEXAFLUOROACETONE AND ACETONITRILE ON AEROBIC PHOTOLYSIS OF (HBPZ(3))REO(C2O4)

Photolysis of (HBpz(3))ReO(C2O4) (HBpz(3) = hydrotris(1-pyrazolyl)bora te) in hexafluoroacetone/acetonitrile solution in the presence of diox ygen forms I, on the basis of an X-ray crystal structure and spectrosc opic data. The unusual and complex metallacycle is constructed from tw o molecules of hexafluoroacetone, one molecule of acetonitrile, and ha lf of the original oxalate ligand. The formation of the metallacycle a nd the results of an isotope-labeling study are rationalized by a mech anism involving a cascade of electrocyclic reactions.