SYNTHESIS AND REACTIVITY OF METAL-CONTAINING MONOMERS .47. SYNTHESIS AND STRUCTURE OF SALTS OF UNSATURATED DICARBOXYLIC-ACIDS

Acid and neutral Co-II, Cu-II Ni-II, Zn-II, Fe-II, and Fe-III maleates , fumarates, and itaconates were obtained and characterized. The metho ds for their synthesis were optimized, and tile valence state and coor dination of metals were studied. Co-II and Fe-II hydrogen maleates, Co -II maleate, and Co-II fumarate were examined by X-ray diffraction ana lysis. The ligands based on unsaturated dicarboxylic acids can be mono -, bi-, and tetradentate, which results in the formation of acid salts , chain acid three-dimensional coordination polymers, whose double bon d is not involved in the coordination. The strong antiferromagnetic ex change (mu(eff) = 1.41 and 0.34 mu(B) at 290 and 80 K, respectively) w as detected in Cu-II itaconate, Based on the data of Mossbauer spectro scopy, the partial reduction of Fe-III to Fe-II during the synthesis o f Fe-III maleate was shown to occur. delta Fe = 0.43 and 1.27 mm s(-1) , Delta E-Q = 0.57 and 3.13 mm s(-1) and Gamma = 0.37 and 0.28 mm s(-1 ) at T = 298 K for Fe-III and Fe-II, respectively.