The reaction of 1,1′-Fe(cpPPh2)2with HgX2(X = Cl, Br, I, SCN) gives Fe(cpPPh2)2·nHgX2(n = 1,2). Infrared, electronic absorption, polarographic, and 57Fe Mossbauer spectroscopic data are presented to show that in every case it is the phosphorus not the iron atom that is bonded to the mercury. The reaction of 1,1′-Fe(cpPPh2)2with Hg(CN)2in the presence of acid gives [(Fe(cpPPh2)2)2Hg](X)2(X-= BF4-, PF6-) where physical data show that the dication has a P-Hg interaction. Ruthenocene reacts with SnX4(X = Cl, Br) to give compounds with Ru-Sn bonds. The products of the reaction of 1,1′-Fe-(cpPPh2)2and SnX4are described.