Structure of bis(Lidocaine) tetrachloridocuprate(II)

The present paper reports on the synthesis and structure of bis(2-(diethylamino)-N-(2,6-dimethylphenyl)acetamide) or bis(lidocaine) tetrachloridocuprate(II). The complex with the formula (C14H23ON2)2CuCl4 (or (LidH)2[CuCl4]) crystallizes in the monoclinic space group P21/c with a = 15.7831(2), b = 24.2992(2), c = 17.8748(2) Å, β = 104.874(1)°,V = 6625.58(13) ų, Z = 8, and Dc = 1.355 Mg/m³. The coordination of the Cu²⁺ ions with chlorine atoms generates two differently distorted tetrahedral anions [CuCl4]^2–, while four protonated cations LidH⁺ remain in an outer coordination sphere. Anions and cations are associated by hydrogen bonds of the N–H···Cl type to form the 2((LidH)2[CuCl4]) molecular dimer, in which the distance between two copper atoms is 8.95 Å. With the help of hydrogen bonds of the type N–H···O and N–H···Cl, each dimer is connected with four neighboring dimers, resulting in a three-dimensional hydrogen-bonded network in which dimers lie at an angle of 28.39° to the a crystallographic axis in the ab planes located at a distance of 10.67 Å from each other.