Anion-dependent complexation of 2-amino-benzothiazole and 2-imino-3-allyl-benzothiazole with Cu+: synthesis and characterization of [Cu(η 2-C10H10SN2)(C7H6SN2)NO3] and [Cu(C7H6SN2)2]ClO4

Abstract

Interaction of 2-amino-benzothiazole with allyl chloride in ethanol resulted in a mixture of 2-imino-3-allyl-benzothiazole and unreacted 2-amino-benzothiazole. Using such a mixture and copper(II) nitrate trihydrate in ethanol – acetonitrile and alternating-current electrochemical technique, crystals of [Cu(η 2-C10H10SN2)(C7H6SN2)NO3] (1) π-complex, containing 2-imino-3-allyl-benzothiazole and 2-amino-benzothiazole coordinated to copper, have been obtained. The same procedure, starting from copper(II) perchlorate hexahydrate, performed in ethanol, led to formation of [Cu(C7H6SN2)2]ClO4 (2) σ-compound. Both compounds were structurally characterized. In the structure 1, 2-imino-3-allyl-benzothiazole is a chelate, bound to metal by C=C-bond of the allyl and nitrogen of the imino group. Another nitrogen from the thiazole core of 2-amino-benzothiazole and oxygen from complete a distorted trigonal-pyramidal environment of copper. [Cu(η 2-C10H10SN2)(C7H6SN2)NO3] building blocks are interconnected into infinite chains via N–H···O () hydrogen bonds and further linked into 3-D structure via π–π stacking between benzothiazole cores. In 2, Cu+ coordinates two nitrogens from two 2-amino-benzothiazoles, whereas locates outside the coordination sphere, fixed in space by N–H···O hydrogen bonds, which form puckered ribbons.