Chemical and x-ray structural characterization of diphenylcarbazone and diphenylthiocarbazone complexes of molybdenum(VI), ( n-Bu 4N)[MoO 2(C 6H 5NNC(X)NNC 6H 5)(C 6H 5NNC(X)NN(H)C 6H 5)] (X = O or S) and ( n-Bu 4N)[MoOCl 3(C 6H 5NNC(O)NNC 6H 5)]; isolation of 2,3-diphenyltetrazolium-5-thiolate, C 6H 5NNC(S)NNC 6H 5, from the reaction of diphenylthiocarbazone with molybdate

Abstract

Reaction of α-(Bu 4N) 4[Mo 8O 26] with diphenylcarbazone (dpcH 2) yields the red crystalline complex (Bu 4N)[MoO 2(C 6H 5NNC(O)NNC 6H 5)(C 6H 5(H)NNC(O)NNC 6H 5)] ( I), a complex displaying two distinct chelate ring types. Treatment of I with HCl yields (Bu 4N)[MoOCl 3(C 6H 5NNC(O)NNC 6H 5)] ( III), a pseudo-octahedral complex with the [MoOCl 3] + core. The reaction of α-(Bu 4N) 4[Mo 8O 26] with diphenylcarbazone (dptcH 2) gave a complex analogous to I, (Bu 4N)[MoO 2(C 6H 5NNC(S)NNC 6H 5)(C 6H 5(H)NNC(S) NNC 6H 5)] ( II) and, surprisingly, 2,3-diphenyltetrazolium-5-thiolate, C 6H 5NNC(S)NNC 6H 5 ( IV). Complex I displays a pseudo-octahedral geometry with MoO 4N 2 coordination and presents distinct geometries for the chemically inequivalent ligand types (dpc) 2− and (dpcH) −. The structure of II is analogous to that of I with MoO 2N 2S 2 coordination geometry but, more significantly, reveals the site of protonation of the (dptcH) − ligand as the terminal exocyclic nitrogen. Crystal data: I, monoclinic space group P2 1/ n, a = 11.026(3), b = 21.600(5), c = 18.851(4) Å, β = 98.04(1)°, V = 4445.1(12) Å 3, 2804 reflections, R = 0.065; II, monoclinic space group P2 1/ c, a = 12.209(3), b = 20.090(4), c = 19.097(2) Å, β = 96.45(1)°, V = 4654.4(9) Å 3, 3835 reflections, R = 0.047; III, P2 1/ n, a = 14.853(2), b = 15.698(4), c = 17.062(4) Å, β = 90.10(1)°, V = 3978.2(10) Å 3, 3128 reflections, R = 0.082; IV, C2/ c, a = 14.755(2), b = 12.193(2), c = 6.958(2) Å, β = 97.42(2)°, V = 1241.3(8), 1055 reflections, R = 0.047.