X-RAY STRUCTURAL INVESTIGATION OF PARAMAGNETIC MOLECULAR-COMPOUND OF 2,5,9,12-TETRAMETHYL-1,8-CIS-1,4,8,11-TETRAAZACYCLOTETRADECA-4,11-DIENENICKEL(II) DIPERCHLORATE,TRANS-DIAQUO-2,5,9,12-TETRAMETHYL-1,8-TRANS-1,4,8,11-TETRAAZACYCLOTETRADECA-4,11-DIENENICKEL(II) DIPERCHLORATE, AND WATER 2[CIS-C14H28N4NI](CLO4)2.[TRANS-C14H28N4NI.2H23](CLO4)2.2H2O

The structure of molecular compound I (2 IA·IB·2H2O), where IA is a square-planar 2(e),5,9(a),12-tetramethyl-1,8-cis-1,4,8,11-tetraazacyclotetradeca-4,11-dienenickel(II) diperchlorate and IB is an octahedral trans-diaquo-2(e),5,9(e),12-tetramethyl-1,8-trans-1,4,8,11-tetraazacyclotetradeca-4,11-dienenickel(II) diperchlorate has been investigated by X-ray diffractometric methods. Compound I crystallizes in an orthorhombic system, space group Pbca, Z=12, a=26.321(3), b=19.919(2), c=13.306(1) Å. The structure was solved by the heavy-atom method followed by a series of Fourier syntheses and refined by full-matrix least-squares to give R=0.060 (for 3757 independent reflections). Conformations were ascribed to chelate rings and to the macrocyclic rings of IA and IB, and the results were compared with those of some known 1,4,8,11-tetraazacyclotetradeca-4,11-dienenickel(II) complexes. The relative configurations were found 1RS,2SR,8RS,9RS (a racemate) for IA and 1R,2S,8S,9R (a meso-form) for IB. They differ each from the other by configuration on one nitrogen centre (N-epimeric compounds). © 1990 Plenum Publishing Corporation.