Syntheses, crystal structures and spectroscopy of di/tri/tetranuclear discrete and co-crystalline copper(II)–NaI/ZnII/CdII complexes derived from a compartmental ligand: Inconsistency in the shifting of the copper(II) d–d band

• DOI: 10.1016/j.poly.2013.06.041
• Publication Date: 2013-07-05T06:03:00Z
• Authors: Sagarika Bhattach...; Arpita Jana; Sasankasekhar Moh...
• Keywords: 01 natural sciences; 0104 chemical sciences

Abstract The work in this report presents the syntheses, characterization, crystal structures and electronic spectra of the six heteronuclear complexes [CuIIL1NaI(μ-BF4)2NaIL1CuII]·2CH3COCH3 (1), [CuIIL1NaI(NO3)(MeOH)] (2), [CuIIL1ZnII(H2O)2L1CuII](ClO4)2 (3), [CuII(MeOH)L1ZnIICl2] (4), [CuIIL1CdII(H2O)(MeOH)2](ClO4)2 (5) and [CuIIL1CdIICl2(MeOH)]·[CuII(MeOH)L1CdIICl2] (6), where H2L1 is N,N′-ethylenebis(3-methoxysalicylaldimine). The crystal systems and space groups are as follows: 1 and 2, triclinic, P 1 ¯ ; 3 and 6, monoclinic, P21/c; 4, orthorhombic, P212121; 5, monoclinic, C2/c. While the N(imine)2O(phenoxo)2 compartment accommodates the copper(II) center, the larger and open O(phenoxo)2O(methoxy)2 compartment interacts with the second metal ion. Compounds 2, 4 and 5 are diphenoxo-bridged dinuclear systems, compound 3 is a trinuclear system in which the two CuIIZnII pairs are monophenoxo-bridged, compound 1 is a tetranuclear system in which two diphenoxo-bridged CuIINaI units are interlinked by two tetrafluoroborate moieties, and compound 6 is a [2×1+2×1] co-crystal of two dinuclear CuIICdII units. The solid state electronic spectra of compounds 1–6 and also the mononuclear compound [CuIIL1(H2O)] have been recorded in the range 400–800 nm. While correlating the d–d band position with the structural parameters and a previously proposed correlation, some inconsistency has been found, indicating that this area should be explored further.