| Abstract: The title complex [Mn(EDTB)](NO3)2·DMF [EDTB=N,N,N′,N′-tetrakis-[(2-benzimidazolyl) methyl]-1,2-ethanediamine] has been synthesized and characterized by elemental analysis and single crystal X-ray diffraction method. The crystal of mononuclear Mn(Ⅱ) complex belongs to orthorhombic crystal system with space group, P212121, a=1.172 52(6) nm, b=1.320 83(6) nm, c=2.461 91(12) nm, V=3.812 8(3) nm3, Dc=1.451 Mg·m-3, Z=4, F(000)=1 732. The final R(I>2σ(I)): R1=0.052 2, wR2=0.102 2 and R (all data): R1=0.065 2, wR2=0.107 5, Flack parameter: 0.02(15) . The manganese(Ⅱ) atom of the cation has distorted octahedral coordination geometry and is six-coordinated by four nitrogen atoms of the benzimidazole groups and two tertiary amine nitrogen atoms from the ligand. Polyphenol oxidase activity toward pyrogallol has been studied spectroscop ically. In the 0.1~10 μmol·L-1 rang, promotion rates of the complex increase from 51.5% to 82.2%． The turnover numbers of the complex toward pyrogallol increase from 22.93 h-1 to 51.01 h-1 at 30 ℃, showing polyphenol oxidase activity of the complex increasing with pH. CCDC: 771022. |
