Comproportionation and redox catalyzed isomerization of Cu(II)(1R,4S,8R,11S-1,4,8,11-tetramethyl-1,4,8,11-tetraaza-cyclotetradecane)2+ in aqueous solutions

The complex Cu(II)(1R,4S,8R,11S-tmc)(2+) comproportionates and isomerizes in the presence of excess of ligand and Cu degrees in alkaline aqueous solutions to yield Cu(II)(1R,4R,8S,1S-tmc)(2+). The visible and EPR spectra of the two complexes as well as their electrochemical properties are reported. The complexes Cu(II)(1R,4R,8S,11S-tmc)(ClO4)(2) and [Cu(II)(1R,4S,8R,11S-tmc)](2)N-3(ClO4)(3) were isolated and crystallographically characterized. (C) 2001 Elsevier Science B.V. All rights reserved.