Copper(I) complexes of a heavily fluorinated beta-diketiminate ligand: synthesis, electronic properties, and intramolecular aerobic hydroxylation.

The aza-Wittig reaction between Ar(f)()-N=PPh(3) [Ar(f)() = 3,5-(CF(3))(2)C(6)H(3)] and 1,1,1,5,5,5-hexafluoro-2,4-pentanedione affords a new, highly fluorinated beta-diketimine, 1. Metalation by mesitylcopper(I) in benzene gives rise to the Cu(I) beta-diketiminate as its eta(2)-benzene adduct, 2a. Copper(I) carbonyl complexes of 1, and of three less-fluorinated analogues, have been generated in situ and compared by IR spectroscopy; the two backbone CF(3) groups exert a stronger electronic influence than the four N-aryl CF(3) groups. Dinuclear adduct 2b reacts readily with O(2), leading to ortho-hydroxylation of a ligand N-Ar(f)() group.