Coordination Chemistry of Anticrowns. Isolation of the Chloride Complex of the Four-Mercury Anticrown {[(o,o′-C6F4C6F4Hg)4]Cl}- from the Reaction of o,o′-Dilithiooctafluorobiphenyl with HgCl2 and Its Transformations to the Free Anticrown and the Complexes with o-Xylene, Acetonitrile, and Acetone