
%0 Journal Article
%A Comba, P 
%A Lawrance, GA 
%A Manning, TM 
%A Markiewicz, A 
%A Murray, KS 
%A Oleary, MA 
%A Skelton, BW 
%A White, AH 
%T Synthesis, Crystal Structure and Magnetism of a Macrocyclic Binuclear Dicopper(II) Amino Alcohol Complex From a Metal Directed Reaction Involving Formaldehyde and Nitroethane
%J Australian Journal of Chemistry
%D 1990/01/01
%V 43
%N 1
%P 69-78
%K 
%R https://doi.org/10.1071/CH9900069
%U https://www.publish.csiro.au/paper/CH9900069 
%X Condensation of the bis (1,5-diaminopentan-3-ol) dicopper (II) ion with formaldehyde and nitroethane in basic methanol yields the macromonocyclic  ligand 3,13-dimethyl-3,13-dinitro-1,5,11,15-tetraazaeicosane-8,18-diol as the dicopper (II) complex. The perchlorate salt of the binuclear complex is very strongly antiferromagnetically coupled, with the magnetic properties measured from 10-300 K identifying a singlet-triplet energy gap of -860 cm-1 and a magnetic moment at room temperature of 0.48 BM. The discrete, binuclear nature of the complex was confirmed by a crystal structure analysis of the nitrite salt, which crystallizes in the monoclinic space group C2/c, a 14.789(6), b 14.560(6), c 12.759(9)&#506;, &#946; 99.65(4)&#176;, and consists of the centrosymmetric macrocycle containing two copper ions each coordinated by two secondary nitrogen donors and two (shared) RO- groups, with water and nitrite oxygens occupying axial sites. The macrocycle donors and the copper ions are essentially coplanar. The Cu&#8230;Cu distance is 3.031(1)&#506;, with the Cu-O--Cu angle 103.6(2)&#176;. The nitro (and methyl) groups at extremities of the macrocycle are in anti dispositions. 
