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274ChemInform Abstract Condensation of bis(ethylenediamine)copper(II) in MeOH with formaldehyde and nitroethane in the presence of bases such as NEt3 or triethanolamine (55 rc C, 2 h) gives a macrocyclic tetraamine complex as a racemic/meso mixture (Ia):(Ib) = 3:1 and the related complex (IIa) as the major products, which can be separated chromatographically and are obtained as their perchlorate salts. Reduction ofthe nitro groups of these complexed ligands may be achieved by Zn or Sn in acid or by catalytic hydrogenation; the former leads to some fragmentation of the precursor macrocyclic ligands during reduction, while the latter yields the amine cleanly. The reduced complexes have been identified, the meso form of (I) being the major product. Additionally the complex (III) could be observed in the react ion mixture. (I) and (II) show no evidence for coordination of the pendant NO2 ligands or their reduced form. (Id) (space group P21/c, Z=2) and (III) (space group P21/c, Z=4) have been characterized crystallographically. An electrochemical investigation shows that all nitro-substituted complexes exhibit an one-electron Cu(II)/Cu(I) couple and a multielectron irreversible wave assigned to NO2 → NHOH. In the pendant amine complexes the nitro reduction wave is absent, and the Cu(II)/Cu(I) couple is shifted to a different potential. The copper(I) compounds are not stable on the coulometric time scale.

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Curtis : Some Cyclic Tetra-amines Some Cyclic Tetra-arnines and their Metal-ion Complexes. Part I .Two Isomeric Hexamethyltetra-axacyclotetradecanes and their Copper( 11) and Nickel(I1) Complexes.By N. F. CURTIS.A cyclic Schiff base-amine complex of nickel(II), formed by condensation of nickel(I1)-ethylenediamine complexes with acetone, can be reduced to form two isomeric cyclic tetra-amine-nickel(I1) complexes. These are decomposed by cyanide ions, releasing the isomeric cyclic tetra-amines, which re-form the original nickel(1r) complexes on reaction with nickel@) salts, and form isomeric complexes with other metal ions. The amines, hydrochloride salts, and copper(I1) and nickel(1r) complexes are described.THE cyclic Schiff base-amine complex of 5,7,7,12,14,14-hexamethyl-1,4,8,1l-tetra-azacyclotetradeca-4,ll-dienenickel(II) (I) formed by the reaction of ethylenediaminenickel complexes with acetone,l,2 is readily reduced, to give two isomeric cyclic tetra-amine-nickel