Reduction of the nickel (11) complex of C-meso-5,7,12,14-tetramethyl-l,4,8,11 -tetra-azacyclotetradeca-4,11diene with NaBH, gives predominantly the nickel(l1) complex of the title ligand, La. Both orange (1) and violet (2) isomers of NiLa(C10J2 have been characterised and structures established by X-ray crystallography. Crystals of (1) are monoclinic. space group P2,lc with two formula units in a unit cell of dimensions a = 8.244(1), b = 8.656(1), c = 16.701 (1) A, and p = 110.28(1)". Crystals of (2) are triclinic, space group P'i with two formula units in a cell of dimensions a = 10.645(1), b = 8.298(1), c = 14.198(2) A, 01 = 121.36(1), p = 94.61 ( l ) , and y = 82.77(1)". Both structures were solved by the heavy-atom method and refined by full-matrix least-squares calculations. For (1 ), R = 0.036 for 2 434 observed reflections; for (2), R = 0.043 for 1 924 observed reflections. Orange complex (1) contains ionic perchlorate with the closest Ni O contact 2.808(5) A. In the centrosymmetric square-planar cation the Ni-N distances are 1.964(3) and 1.974(3) A. The purple complex (2) contains two independent discrete half molecules (2a) and (2b) lying on inversion centres in the asymmetric unit, both with axially bound perchlorate. Principal distances are Ni-0 2.235(3) and 2.221 (2) A and Ni-N 2.063(2)-2.081(2) A. The metal complexes have the trans Ill arrangement of the chiral nitrogen centres, with the four methyl groups equatorial. The complex [NiL,J2+ undergoes axial additions with unidentate ligands (HzO, Br-, CI-, NCS-, N3-, NO2-, 02CMe-) and trans-[NiLX2]"+ have been prepared and characterised. Infrared and d-d spectra are reported. The equilibrium [NiLJ2+ + 2H20 + [NiLa(OH2)2]2+ha~ been studied over a temperature range, yielding K = 5.06 at 25 "C with AH* = -22.1 kJ m o l -l and A S ' = -60.6 J K -l mol-l. KOLINSKI A N D KORYBUT-DASZKIEWICZ first described the nickel(I1) complexes of the macrocyclic ligand 5,7,12,14tetramet hyl-1,4,8,11-t etra-azac yclo t et radeca-4,11 -diene (I) (=L). The ligand contains two chiral carbon centres at C7 and C14 so that C-rac (11) and C-meso (111) diastereo- C-meso ( R , S

Amberlite XAD-2 has been functionalized by coupling through -SO 2 -with ethylenediamine, propylenediamine, and diethylenetriamine to give the corresponding polyamine chelating resins I-III. The solid metallopolymer complexes of the synthesized chelating resins with Cu 2ϩ , Zn 2ϩ , Cd 2ϩ , and Pb 2ϩ were synthesized. The polyamine derivatives and their metal complexes were characterized by elemental analysis, spectral (IR, UV/V, and ESR), and magnetic studies. The batch equilibrium method was utilized for using the chelating polyamines for the removal of Cu ϩ2 , Zn ϩ2 , Cd ϩ2 , and Pb ϩ2 ions from aqueous solutions at different pH values and different shaking times at room temperature. The selective extraction of Cu ϩ2 from a mixture of the four metal ions and the metal capacities of the chelating resins were evaluated using atomic absorption spectroscopy.

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