Systematic Structural Coordination Chemistry of p-tert-Butyltetrathiacalix[4]arene: Further Complexes of Transition-Metal Ions

In extension of earlier work on complexes of p-tert-butyltetrathiacalix[4]arene, LH4, with late transition-metal M-II species, we report studies of complexes modelled on the basis of single-crystal X-ray studies as derivatives of V-V, W-II M-II, Fe-III, Ni-II, Cu-II and Pd-II, the last as a trio of heteronuclear species also involving Ca-II. In complexes (VO(OH)(LH2)center dot 2.5dmf center dot 2H(2)O] (x2) (1), Cl2W(L)center dot 3.5C(6)H(6) (2) and [Mn(LH2)center dot 3.5CH(2)Cl(2)] (x2) (3) included dmf is found only in the partially deprotonated calixarene cavities of 1 and 3. In oligonuclear OFe3(HCO2)(LH)(2)center dot 2H(2)O center dot 6dmf (4) and 2Cuac(2)center dot Cu-2(L)center dot dmf center dot 4.5CH(2)Cl(2) (6) (ac = acetate) included dmf is found in both. Ni-II provides several species, including 5a, binuclear (Et3NH)Ni-2(LH)(LH2)center dot 2dmf center dot 2Me(2)CO center dot H2O, 5b, a remarkable hexanuclear (binuclear + tetranuclear) aggregate, Ni-6(L)(LH)(2)-(LH2)center dot 4MeCN.6H(2)O, and 5c, an even more remarkable Ni-32 aggregate modelled as (centrosymmetric) Ni-32(OH)(40)(L)(6)center dot 8dmso center dot 10dmf, in which there are two sets of nickel atoms, one disposed at the corners of a cube (Ni-8), the other (Ni-24) at the vertices of a cuboctahedron (the Ni-8 vertices at the centres of the hexagonal faces); the hydroxy groups comprise two sets: one, (OH)(24), disposed outside the spheroidal shell of nickel atoms, the other, (OH)16, disordered within, the thia-calixarene ligands L-6 being disposed about the axes of the octahedron. Heteronuclear species have been found as Ca-II/Pd-II combinations CaPd2(LH)(2)center dot 1.5CH(2)Cl(2) (7a), CaPd(LH2)center dot 3dmso center dot H2O center dot 4.5MeCN (7b), Ca2Pd(LH)(2)center dot 3.5dmso center dot 1.5H(2)O center dot 4MeCN (7c), all with included solvent.