Versatile CoII and NiII mononuclear complexes with furoate/ thiophencarboxylate anions and 3,5-dimethylpyrazole- Synthesis, structure, magnetic, catalytic and antimycobacterial properties

Series of complexes of the composition [M(L)2(Hdmpz)n] (L = fur, M = CoII, n = 2 (1), n = 4 (2), M = NiII, n = 2 (3), L = tph, M = CoII, n = 2 (4), M = NiII, n = 2 (5), n = 4 (6)) has been obtained by interaction of cobaltII and nickelII acetates with 3-furancarboxylic (Hfur) or 2-thiophencarboxylic (Htph) acids, followed by the addition of 3,5-dimethylpyrazole (Hdmpz). According to the X-ray data in complex 1 - 6 , metal atoms are surrounded by carboxylate anions and two or four monodentately coordinated Hdmpz molecules. Additional stabilization of the complexes is carried out by the inter- and intramolecular hydrogen bonds. Co and Ni catalysts obtained by chemical activation of 1 and 3 exhibit high catalytic activity in a continuous dicyclopentadiene (DCPD) hydrogenation process at atmospheric hydrogen pressure. Slow relaxation of magnetization has been found for complexes by use of ac-magnetometry for compounds 1 and 4 at 1000 Oe dc-field in contrast with 2, 3, 5, 6 exhibiting no slow magnetic relaxation. Biological activity of 1 - 6 has been determined against a non-pathogenic strain of Mycobacterium smegmatis.