ISSN:
1572-8854
Source:
Springer Online Journal Archives 1860-2000
Topics:
Geosciences
,
Physics
Notes:
Abstract The structure of molecular compoundI (2IA·IB·2H2O), whereIA is a square-planar 2(e),5,9(a),12-tetramethyl-1,8-cis-1,4,8,11-tetraazacyclotetradeca-4,11-dienenickel(II) diperchlorate andIB is an octahedraltrans-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 groupPbca, 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 giveR=0.060 (for 3757 independent reflections). Conformations were ascribed to chelate rings and to the macrocyclic rings ofIA andIB, 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) forIA and 1R,2S,8S,9R (ameso-form) forIB. They differ each from the other by configuration on one nitrogen centre (N-epimeric compounds).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01187253
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