Re-refinement of Crystal Structure of Bis(Lidocaine) Diaquatetrathiocyanatonickelate(II)

Abstract

This paper reports on the synthesis and structure re-refinement of bis(lidocaine) diaquatetrathiocyanatonickelate(II). The compound with the formula (LidH)2[Ni(NCS)4(H2O)2], where Lid is (2-(diethylamino)-N-(2,6-dimethylphenyl)acetamide, crystallizes in the monoclinic space group P21/c with a= 18.3509(5), b= 7.6532(2), c= 14.9585(4) Å, β= 109.964 (2)°, V= 1974.57 (9) Å 3 , and Z= 2. Coordination of the Ni 2+ ion with thiocyanate ions and water molecules generates the slightly distorted octahedral anion [Ni(NCS)4(H2O)2] 2– with N-bonded thiocyanate groups, while two protonated cations LidH + remain in an outer coordination field. The anion and cations are associated through hydrogen bonds formed by sulphur atoms with amido nitrogen atoms; water molecules and an amino nitrogen atom are involved in the formation of hydrogen bonds with sulphur atoms of neighbouring unit cells arranging alternating [Ni(NCS)4(H2O)2] 2– anions and LidH + cations into endless sheets lying in the ac plane.