Two New Salts Based on Bis(1,2,5-thiadiazole-3,4-dithiolate)nickelate Anion with Substituted Benzyl 4-ethylpyridinium: Syntheses, Crystal Structures and Properties

Two new salts based on [Ni(tdas) 2 ] 2− (tdas 2− = 1,2,5-thiadiazole-3,4-dithiolate) anion, [Bz4EtPy] 2 [Ni(tdas) 2 ] ( 1 ) and [4ClBz4EtPy] 2 [Ni(tdas) 2 ] ( 2 ), have been prepared by reaction of Na 2 tdas, NiCl 2 ·6H 2 O, and [Bz4EtPy]Br ([Bz4EtPy] + = 1-benzyl-4-ethylpyridinium) or [4ClBz4EtPy]Br ([4ClBz4EtPy] + = 1-(4′-chlorobenzyl)-4-ethylpyridinium), and characterized by elemental analyses, UV, IR, MS spectrum, molar conductivity and single crystal X-ray diffraction. Single-crystal X-ray diffraction analyses indicate that the two salts crystallize in a triclinic system with space group P −1. The unit cell contains two [Bz4EtPy] + /[4ClBz4EtPy] + and one [Ni(tdas) 2 ] 2− anion in which the anion exhibits a quasi-planar structure. The crystals of 1 and 2 are stabilized through C–H···S and C–H···Ni hydrogen bonds, π···π stacking interactions and S···Cl short interactions. Graphical Abstract In two new salts based on [Ni(tdas) 2 ] 2− (tdas 2− = 1,2,5-thiadiazole-3,4-dithiolate) anion, [Bz4EtPy] 2 [Ni(tdas) 2 ] ( 1 ) and [4ClBz4EtPy] 2 [Ni(tdas) 2 ] ( 2 ), the unit cell contains two cations and one [Ni(tdas) 2 ] 2− anion, and C–H···S and C–H···Ni hydrogen bonds, π···π stacking interactions and S···Cl short interactions are founded.