Cyclometallation of ferrocenylimines III. Regioselectivity in Hg(II) cyclometallated complexes

Article abstract of DOI:10.1016/S0022-328X(97)00211-8

The synthesis and mercuration of a series of Schiff bases 1′-benzoyl-1-[(arylimino)phenylmethyl]ferrocene (aryl: a variety of substituted phenyls) have been studied. In all cases the mercuration occurred at the 2-position of the ferrocene ring. Oxygen → mercury coordinated products were not obtained. The X-ray crystal structure of [2-chloromercurio-1-[((phenylimino)phenylmethyl)-1′-benzoyl] ferrocene 5c has been determined; this crystallizes in the monoclinic, space group P2₁/c with a =10.168(3), b= 16.105(3), c = 15,463(4)A, β = 103.61(2)° and Z = 4. Refinement of atomic parameters gave an R factor of 0.038 (Rω = 0.055) for 2440 unique reflections having 1>3σ(1). The structure confirms the formation of a five-membered metallocycle on the ferrocene moiety.