Crystal structure of bis(dipyrromethene)copper(II)

Abstract

The structure of bis(diethyl 3,3′,5,5′-tetramethyldipyrromethene-4,4′-dicarboxylate)copper(II) in one of its crystalline modifications has been established by X-ray analysis at room temperature. The crystals are monoclinic, space group P2₁/c with a= 8·09, b= 30·16, c= 16·01 Å, β= 91·7° and Z= 4. Blocked least squares refinement using 683 photographically measured intensities led to a conventional R of 12·6%. The two approximately planar dipyrromethene ligands are inclined at an angle of 66°, making the copper environment distorted tetrahedral. The mean Cu–N bond length is 1·99(2)Å. Three other crystalline modifications, one of them stable only at reduced temperatures, have been identified.