N. Attandoh, S. O. Ojwach, O. Munro
Jul 1, 2014
Citations
0
Influential Citations
22
Citations
Journal
European Journal of Inorganic Chemistry
Abstract
Compounds N-(1H-benzimidazol-2-ylmethyl)aniline (L1), N-(1H-benzimidazol-2-ylmethyl)-2-bromoaniline (L2), and N-(1H-benzimidazol-2-ylmethyl)-2-aminothiophenol (L3) react with ZnII and CuII carboxylates to form complexes [Zn2(L1)2(OBn)4] (1), [Zn2(L2)2(OBn)4] (2), [Zn2(L3)2(OBn)4] (3), [Cu2(L2)2(OBn)4] (4), [Zn(L1)2(OAc)2] (5), [Zn(L2)2(OAc)2] (6) and [Cu2(L1)2(OAc)4] (7). Structures of 2, 4 and 6 revealed that L1–L3 are monodentate, binding through the imidazolyl N-atom. The X-band EPR spectrum of 4 in the solid state is consistent with an antiferromagnetically-coupled (singlet) ground state and a low-lying EPR-active triplet excited state characterised by two main transitions. In dimethyl sulfoxide (DMSO) solution, a single resonance confirmed the retention of the dinuclear paddlewheel core. Complexes 1–7 formed active catalysts towards ring-opening polymerisation of ϵ-caprolactone. The polymerisation reactions follow first-order kinetics with respect to the monomer and occur through a coordination–insertion pathway.