This Communication describes the reaction between Ni(PPh3)4 and 2,2’-dibromodiphenyl, leading to the isolation of an unprecedented κ1-o-diphenyl-nickel(II) square planar complex. Full NMR characterization and the X-ray crystal structure of the title compound are reported. Preliminary investigations on the mechanism conducting to the isolated species are presented. The results of control experiments carried out using 1,1-diphenylethylene as a radical scavenger are consistent with a radical pathway rather than a double oxidative addition of the diaryl substrate. DFT calculations on the transition states involved supported these observations.
Cinco et al. (Mon,) studied this question.