Synthese, Strukturen, NMR‐ und EPR‐Untersuchungen der binuklearen Bis(N,N,N‴,N‴‐tetraisobutyl‐N′,N″‐isophthaloylbis(selenoureato))‐Komplexe des NiII und CuII

Synthesis, Structures, NMR and EPR Investigations of Binuclear Bis(N,N,N‴,N‴‐tetraisobutyl‐N′,N″‐isophthaloylbis(selenoureato)) Complexes of NiII and CuII The synthesis of binuclear CuII and NiII complexes of the quadridentate ligand N,N,N‴,N‴‐tetraisobutyl‐N′,N″‐isophthaloylbis(selenourea) and their crystal structures are reported. The complexes crystallize monoclinic, P21/c (Z = 2). In the EPR spectra of the binuclear CuII complex exchange‐coupled CuII‐CuII pairs were observed. In addition the signals of a mononuclear CuII species are observed what will be explained with the assumption of an equilibrium between the binuclear CuII‐complex (CuII‐CuII pairs) and oligomeric complexes with “isolated” CuII ions. Detailed 13C and 77Se NMR investigations on the ligand and the NiII complex allow an exact assignment of all signals of the heteroatoms.