Subtlety in the reactivity of a diketo phosphorus ylide towards mercuric halides: the unprecedented O-coordination of α-acetyl-α-benzoylmethylenetriphenylphosphorane to Hg(ii)

Abstract

The reactions of the title ylide with HgX2 (X = Cl, Br or I) lead to the regiospecific binding of the acetyl oxygen to soft Hg(II), producing a chloro complex with (2 + 2) coordination and isostructural dimeric bromo and iodo complexes containing halogen bridges with tetrahedral configurations around the metal centres.