Synthesis and spectroscopic characterization of tris(O,O′-ditolyl dithiophosphato) arsenic/antimony/bismuth(III) compounds: Crystal structures of [As{S2P(OC6H4Me-m)2}3]·0.5C6H14, [Sb{S2P(OC6H4Me-m)2}3] and [Bi{S2P(OC6H4Me-m)2}3]

Arsenic(III), antimony(III) and bismuth(III) compounds of the type, [M{S2P(OR)2}3] (where M = As, Sb and Bi; R = o-, m-, p-C6H4Me) were obtained by reactions of MCl3 with ammonium salts of the corresponding O,O′-ditolyl dithiophosphate on refluxing in benzene. These compounds were characterized by elemental analysis, IR, 1H NMR and 31P NMR spectroscopy. The single crystal X-ray structures of three representative compounds were determined. [As{S2P(OC6H4Me-m)2}3]·0.5C6H14 crystallizes as triclinic in the space group P1¯ with a = 10.9396(1), b = 14.1891(2), c = 17.5359(2) Å, α = 70.731(1), β = 84.734(1), γ = 74.205(1)°,Z = 4, V = 2472.37(5) Å3. [Sb{S2P(OC6H4Me-m)2}3] and [Bi{S2P(OC6H4Me-m)2}3] both crystallize as monoclinic in the space group P21 with a = 12.4520(3), b = 22.8760(5), c = 16.2165(4) Å, β = 93.022(1)°, Z = 4, V = 4612.9(2) Å3 and with a = 12.4903(2), b = 22.9554(4), c = 16.1032(3) Å, β = 92.4300(10)°, Z = 4, V = 4612.96(14) Å3, respectively. In all three molecules, the central metal atom is surrounded by all six sulfur atoms of the three chelating anisobidentate O,O′-ditolyl dithiophosphate groups in a pseudo trigonally distorted octahedron with a lone pair positioned on one of the triangular octahedral faces. The three metal sulfur bonds adjacent to the lone pair (capped face) are longer than the three furthest from the lone pair (uncapped face). Inter-ligand angles between the longer bonds are greater than those between the shorter bonds.

Graphical abstractArsenic(III), antimony(III) and bismuth(III) compounds of the type, [M{S2P(OR)2}3] (where M = As, Sb and Bi; R = o-, m-, p-C6H4Me) were obtained. These compounds were characterized by elemental analysis, IR, 1H NMR and 31P NMR spectroscopy. The single crystal X-ray structures of three representative compounds, [As{S2P(OC6H4Me-m)2}3]·0.5C6H14, [Sb{S2P(OC6H4Me-m)2}3] and [Bi{S2P(OC6H4Me-m)2}3] were determined.Figure optionsDownload full-size imageDownload as PowerPoint slide