engleski

Stereochemistry of complexes with N-alkylated amino acids.XII. Crystal structure and molecular mechanics calculations for aquabis(L-N, N-dimethylalaninato) copper(II)hexahidrate

The structure of blue, monoclinic (C2) crystals of trans-aquabis(L-N, N-dimethylalaninato)copper(II) hexahydrate was determined by X-ray diffraction methods and refined to R = 0.026. The structure consists of discrete molecules in the same (equatorial-equatorial) conformation linked together in a comprehensive array of water molecules with the structure resembling that of ice. The copper coordination polyhedron is highly distorted (N-Cu-N = 166.2(1)o and O-Cu-O = 161.5(1)o) and the apical bond lenght (Cu-OW = 2.222(3) A) is extremely short, which is a direct consequence of the distortion of the coordination polyhedron. Conformational analysis shows that the conformation of the molecule in the crystal state is 1.4 kJ mol-1 higher in the energy that the most stable conformer (with axial-axial conformation).

copper; amino acids; X-ray structure; energetics

nije evidentirano