Table of Contents
International Journal of Inorganic Chemistry
Volume 2012, Article ID 973238, 6 pages
Research Article

Structural and Spectroscopic Properties of Two New Isostructural Complexes of Lapacholate with Cobalt and Copper

1Facultad de Ciencias Exactas, Universidad Nacional de Salta, Avenida Bolivia 5150, 4400 Salta, Argentina
2Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Ayacucho 491, 4000 Tucumán, Argentina
3Departamento de Física, Facultad de Ciencias Exactas, Universidad Nacional de La Plata and Institute IFLP (CONICET-CCT La Plata), C. C. 67, 1900 La Plata, Argentina
4Instituto de Física de São Carlos, Universidade de São Paulo, C.P. 369, 13560 São Carlos, SP, Brazil

Received 18 November 2011; Revised 24 January 2012; Accepted 24 February 2012

Academic Editor: Peter Baran

Copyright © 2012 R. A. Farfán et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The molecular structures of two isostructural complexes of lapacholate (Lap) anion and dimethylformamide (DMF), M(Lap)2(DMF)2 with M: Co Cu, were determined by X-ray diffraction methods. The substances crystallize in the triclinic space group with one molecule per unit cell and cell constants (3), (3), (4) Å, (2), (2), and (2)° for the Co complex and (2), (4), (4), (2), (2), and (2)° for the Cu complex. The structures were solved from 2933 (Co) and 2888 (Cu) reflections with (I) and refined by full matrix least squares to agreement R1-factors of 0.041 (Co) and 0.033 (Cu). The metal M(II) ion is sited on a crystallographic inversion center in a MO6 distorted octahedral environment. This ion is coordinated equatorially to two lapacholate anions through their adjacent carbonyl and phenol oxygen atoms [M–O bond distances of 2.134(1) and 2.008(1) Å (Co) and 2.301(1) and 1.914(1) Å (Cu)] and axially to two DMF molecules through oxygen atoms [M–O bond lengths of 2.143(1) Å (Co) and 2.069(1) Å (Cu)]. The solid state IR transmittance and solution electronic absorption spectra of both Co and Cu compounds are also reported and compared to each other and to the corresponding spectra of other members of the lapacholate metal family of complexes.