Trimeric Cage Complexes of Platinum Group and Coin Metals



The treatment of cis,cis-1,3,5-tris(diphenylphosphinomethyl)cyclohexane (tdppmcy) with Rh(CO)Cl(PPh3)2, MCl2L2 (M = Pd, Pt; L = PhCN, MeCN), Pt(CN)2, AgBF4, or Au(Cl)PPh3 in a stoichiometric ratio of 2:3 affords the trimeric macrocyclic cage compounds [M]3(tdppmcy)2 {[M] = trans-Rh(CO)Cl (2), trans-PdCl2 (3), trans-Pt(CN)2 (4b), Ag+ (5), and AuCl (6)} in good yields. Only when PtCl2(PhCN)2 was used as complex precursor, the formation of coordination polymers was observed. NMR spectroscopy in solution as well as single-crystal X-ray diffraction analyses demonstrate that in all cases two tdppmcy ligands coordinate three metal fragments exclusively in trans fashion.