Crystal structure of three chloridocuprate(I, II) complexes with methylene blue (MB) counterions

Abstract Three chloridocuprate complexes with methylene blue counterions of the chemical compositions [MB] + 2 [CuCl 4 ] 2− · H 2 O ( 1 ), [MB] + 2 [CuCl 4 ] 2− ( 2 ) and [(MB) + (CuCl 2 ) − ] 3 ( 3 ) (where [MB] + – methylthioninium cation; methylene blue cation) have been prepared by solvent-assisted mechanochemical synthesis. The reactions were carried out by mixing the copper(II) chloride dihydrate, CuCl 2 ⋅2H 2 O, and methylene blue pentahydrate, [MB] + Cl − · 5H 2 O by grinding in an agate mortar with the addition of DMF as a solvent. The crystal structures of the compounds have been determined by single-crystal X-ray diffraction. The content of an asymmetric unit of the crystals consists of: ( 1 ) a tetrahedral [CuCl 4 ] 2− anion, two [MB] + cations and one water molecule of crystallization; ( 2 ) a tetrahedral [CuCl 4 ] 2− anion and two [MB] + cations; ( 3 ) trimeric [(MB) + (CuCl 2 ) − ] 3 molecules with the Cu atoms coordinated by a nitrogen atom of the phenothiazine ring and two chlorine ions in a trigonal planar geometry with the copper atom in the oxidation state of +1.