A new acesulfamato complex: [Cu(acesulfamato)2(H2O)4]. Structural and spectroscopic characterization

The crystal structure of tetraaqua-bis(6-methyl-1,2,3-oxathiazin-4(3H)-onato 2,2-dioxide) copper(II) complex, for short [Cu(ace)2(H2O)4], was determined by X-ray diffraction methods. The complex crystallizes in the monoclinic C2/c space group with a = 11.9838(4), b = 9.5240(3), c = 15.1686(6) Å, β = 102.975(4)° and Z = 4 molecules per unit cell. The structure was determined from 1609 reflections with I > 2σ(I) and refined to an agreement R1-factor of 0.0345. [Cu(ace)2(H2O)4] is a new member in the family of acesulfamate complexes of first row transition metals, namely [M(ace)2(H2O)4], M: Co, Ni, Zn. It differs from the other members in the bonding of acesulfamate to metal through one of its sulfoxide oxygen atoms. The new complex was further characterized by its infrared, Raman and electronic absorption spectra, which were discussed in comparison with those of other related species.