STEREOCHEMISTRY OF COMPLEXES WITH N-ALKYLATED AMINO-ACIDS .7. CRYSTAL-STRUCTURE OF BIS(N-TERT-BUTYL-N-BENZYLGLYCINATO)COPPER(II) - CONFORMATIONAL-ANALYSIS AND MOLECULAR MECHANICS CALCULATIONS

The structure of the red, monoclinic modification of bis(N-tert-butyl- N-benzylglycynato)copper(II) was solved by X-ray diffraction analysis and refined to R = 0.044. The structure is made up of discrete molecul es with the copper atom (situated at an inversion centre) having squar e-planar coordination with oxygen and nitrogen atoms in trans position s with Cu-O 187.4(2) and Cu-N 2.112(3)angstrom. The results of molecul ar mechanics calculations reveal that the crystal conformation has abo ut 13 kJ mol-1 higher energy than the lowest energy conformation. This suggests the influence of intra- and intermolecular interactions in d efining the molecular conformation.