Observation of a chloride-bridged P-P bond in the phosphorus cation [L(Cl) P(μ-Cl) P(Cl)L]+ (L = NHC)

Article abstract of DOI:10.1021/om4002268

A bridging chloride anion between two electrophilic phosphorus centers was observed for the first time in the molecular structure of the novel P-P bonded cation [L^Dipp₂P₂Cl₃]⁺ (2⁺; L^Dipp = 1,3-bis(2,6-diisopropylphenyl)imidazol-2- ylidene). Cation 2⁺ is prepared by the reduction of the monophosphorus species [L^DippPCl₂]⁺ (1 ⁺) with sodium. DFT calculations, AIM and mechanochemical (compliance constants) analyses are used to examine the bonding situation of this unusual species. The monochloro-substituted cation [L^Dipp₂P ₂Cl]⁺ (3⁺) was likewise observed as a reduction product of 1⁺.