Iron(II), cobalt(II), and nickel(II) complexes with 1,10-phenanthroline and 2,2'-bipyridyl and the macropolyhedral borane cluster [trans-B20H18]2- as counterion

The iron(II), cobalt(II), and nickel(II) complexation with 1,10-phenanthroline (Phen) and 2,2'-bipyridyl (Bipy) have been studied in the presence of the [B20H18](2-) anion. Tris-chelate metal complexes [ML3][B20H18] (M = Fe, L = Bipy (1), Phen (2); M = Co, L = Bipy (3), Phen (4); M = Ni, L = Bipy (5), Phen (6)) have been isolated and characterized by elemental analysis, IR and 11B NMR spectroscopy. It has been found that the composition of nickel(II) and iron(II) complexes with Bipy and Phen and cobalt(II) complex with Bipy could not be changed by varying the ratio of reagents; tris-chelate compounds were isolated when the M: L ratio was equal to 1: 1, 1: 2, and 1: 3 (except for cobalt(II) and Phen). For cobalt, it was found that when the Co: Phen ratio is equal to 2: 1, binuclear cobalt(II) complex [Co-2(Phen)(4)Cl-2][B20H18] (8) was formed. Binuclear complex 8 dissociates in DMF, and mononuclear cobalt(II) complex [Co(Phen)(2)Cl(DMF)]2[B20H18] (9) was isolated. The structures of compounds 1 center dot Bipy center dot 2CH(3)CN, 4 center dot 4CH(3)CN, 4 center dot 5CH3CN, 6 center dot 2DMF, 8 center dot CH3CN and 9.2DMF have been determined by X-ray diffraction.

Automated summary

The complexation of iron(II), cobalt(II), and nickel(II) with 1,10-phenanthroline (Phen) and 2,2'-bipyridyl (Bipy) in the presence of the [B20H18](2-) anion was studied. Tris-chelate metal complexes [ML3][B20H18] were synthesized and characterized. The composition of the complexes could not be changed by varying the ratio of reagents, except for cobalt(II) and Phen, which formed a binuclear complex. The structures of the complexes were determined by X-ray diffraction.