Hc. Lopezsandoval et al., COORDINATION BEHAVIOR OF N-CARBOXYMETHYLPSEUDOEPHEDRINE - CRYSTAL-STRUCTURES OF 7-CO-ORDINATED CADMIUM(II) AND FAC-RS-OCTAHEDRAL COPPER(II)COMPLEXES, Journal of the Chemical Society. Dalton transactions, (19), 1997, pp. 3415-3420
Go-ordination compounds of N-[2-hydroxy 1(R)-methyl-2(R)-phenylethyl]-
N-methylglycine (N-carboxymethyl-pseudoephedrine, Hcpse) with copper(I
I), cobalt(II) and cadmium(II) have been prepared and characterised. C
rystal structures of copper and cadmium complexes were obtained. In th
e compound [Cu(cpse)(2)]. H2O, two cpse are co-ordinated in a tridenta
te mode giving place to a fac-RS-octahedral geometry. The monomeric co
mpound [Cd(cpse)(2)(H2O)] has an uncommon seven-co-ordinate geometry w
ith one cpse bonded in a similar arrangement to that of the copper(II)
compound, with an oxygen from the carboxylate group in an apical posi
tion. The second cpse molecule is co-ordinated with all three atoms in
the equatorial plane, the remaining axial position of the distorted p
entagonal bipyramid being occupied by a water molecule. As for the lat
ter complex, the metal centre of [Cd(cpse)Cl(H2O)]. H2O . dmso (dmso =
dimethyl sulfoxide) presents a distorted pentagonal-bipyramidal geome
try where the apical positions are occupied by a water molecule and a
chloride ion. The tridentate cpse ligand lies in the equatorial plane
and the co-ordination sphere is completed by a chelating carboxylic gr
oup from another cpse ligand. Each carboxylate group of cpse is bridgi
ng two different cadmium atoms, forming a zigzag chain in a polymeric
structure.