Arsenic(III) complexes of substituted diphenyldithiophosphate: synthesis, characterization, single crystal X-ray, DFT, and Hirshfeld surface analysis

Abstract

Reaction of the triethylammonium salt of the substituted diphenyldithiophosphate ligands with AsCl3 in a 3:1 ratio results in the formation of the arsenic complexes As[S2P{OC6H4(4-C2H5)}2]3 (1), As[S2P{OC6H4(4-(CH3)3C)}2]3 (2), As[S2P{OC6H3(2,4-CH3)2}2]3 (3), As[S2P{OC6H3(2,5-CH3)2}2]3 (4), As[S2P{OC6H3(3,4-CH3)2}2]3 (5), and As[S2P{OC6H3(3,5-CH3)2}2]3 (6). The characterization of all the synthesized complexes was done by IR and multinuclear NMR (1H, 13C, and 31P) spectroscopies. Complexes 1 and 2 were structurally elucidated by single-crystal X-ray analysis. The X-ray data reveals that 1 and 2 were crystallized in triclinic crystal system with space group P −1 and monoclinic crystal system with space group C2/c, respectively. In 1 and 2, the coordination geometry around the central arsenic atom is pseudo-trigonally distorted octahedral with a lone pair of electrons positioned on one of the triangular faces of the octahedral. The central As atom in both complexes is surrounded by six sulfur atoms of the chelating anisobidentate ligands. The density functional theory computations are also carried out to further analyze the geometry and quantum chemical parameters in order to support the experimental and structural data. Finally, to estimate the effect of alkyl steric bulk in diphenyldithiophosphate complexes 1 and 2 on the intermolecular contacts contributions to the Hirshfeld surface analysis and 2-D finger-print plots analysis have been employed.