synthesis of two new dinuclear copper(ii) complexes and esr studies ofcopper(ii) – copper(ii) interaction through  system

our main objective is a better understanding of spin spin interaction of dinuclear copper(ii) complexes through  system. the synthesis and characterization of two new dinuclear copper(ii) complexes, based on the use of large, pyrole-containing macrocycles, the so called “ expanded porphyrins” , [cu2(macrocycle)]4+ is described. a chloroform solution spectrum of two complexes taken at room temperature and 130135 k gave a classic electron spin resonance (esr) pattern for both compounds. both complexes show a triplet state(s = 1), with both m = 1 and m = 2 (half field) transition which is the characteristics of cu(ii) cu(ii) dimer. the observation of m = 2 band strongly suggests the spin spin interaction occurs through  system. all compounds exhibit a typical m = 1 transition with superhyperfine splitting due to the 14n bound to copper.