TY - JOUR
T1 - Dinuclear zinc complexes of phenol-based "end-off" compartmental ligands
T2 - Synthesis, structures and phosphatase-like activity
AU - Abe, K. J.
AU - Izumi, J.
AU - Ohba, M.
AU - Yokoyama, T.
AU - Okawa, H.
PY - 2001/1
Y1 - 2001/1
N2 - The phenol-based compartmental ligands of the "end-off" type, 2,6-bis{N-[2-(dimethylamino)ethyl]iminomethyl})-4-methylphenol (HL1), 2-{N-[2-(dimethylamino)ethyl]iminomethyl}-6-{N-methyl-N-[2-(dimethylamino) ethyl]aminomethyl}-4-bromophenol (HL2), 2,6-bis{2-[(2-pyridyl)ethyl]iminomethyl}-4-methylphenol (HL3) and 2-[N,N-di(2-pyridylmethyl)aminomethyl]-6-{N-[2-(dimethylamino)ethyl] iminomethyl}-4-methylphenol (HL4), have formed dinuclear zinc complexes: [Zn2(L1)(AcO)2]PF6 (1), [Zn2(L1)(NCS)3] (2), [Zn2(L2)(AcO)2]PF6 (3), [Zn2(L2)(NCS)3] (4), [Zn2(L3)-(AcO)2]PF6 (5), [Zn2(L3)(NCS)3] (6), [Zn2(L4)(AcO)2]C104 (7), [Zn2(L4)(AcO)(NCS)2] (8) and [Zn2(L4)(NCS)3] (9). The crystal structures of 1, 5·(DMF)0.5(2-PrOH)0.5, 7·CHCl3, 8·(2-PrOH) and 9·3CHCl3 have been determined. Complexes 1 and 5·(DMF)0.5(2-PrOH)0.5 have a di-μ-acetato-μ-phenolato-dizinc(II) core comprised of two square-pyramidal Zn centers. 7·CHCl3 has a similar dinuclear core, but it is comprised of one square-pyramidal Zn and one pseudo-octahedral Zn. 8·(2-PrOH) has a μ-acetato-μ-phenolato-dizinc(II) core with a unidentate thiocyanato-N group on each Zn. 9·3CHCl3 exists in two different crystals: one has a μ-thiocyanato-N-μ-phenolato-dizinc(II) core, whereas the other has a μ-phenolato-dizinc(II) core. The diacetato complexes, 1, 3, 5 and 7, are stable in solution. Hydrolytic activities of the complexes toward tris(p-nitrophenyl) phosphate (TNP) have been studied in aqueous DMF by means of UV-visible spectroscopic and 31P NMR methods. Complexes 1, 3 and 5 have an activity to hydrolyze TNP into bis(p-nitrophenyl) hydrogenphosphate (HBNP) in aqueous DMF. In contrast, 7 showed little hydrolytic activity toward TNP in aqueous DMF.
AB - The phenol-based compartmental ligands of the "end-off" type, 2,6-bis{N-[2-(dimethylamino)ethyl]iminomethyl})-4-methylphenol (HL1), 2-{N-[2-(dimethylamino)ethyl]iminomethyl}-6-{N-methyl-N-[2-(dimethylamino) ethyl]aminomethyl}-4-bromophenol (HL2), 2,6-bis{2-[(2-pyridyl)ethyl]iminomethyl}-4-methylphenol (HL3) and 2-[N,N-di(2-pyridylmethyl)aminomethyl]-6-{N-[2-(dimethylamino)ethyl] iminomethyl}-4-methylphenol (HL4), have formed dinuclear zinc complexes: [Zn2(L1)(AcO)2]PF6 (1), [Zn2(L1)(NCS)3] (2), [Zn2(L2)(AcO)2]PF6 (3), [Zn2(L2)(NCS)3] (4), [Zn2(L3)-(AcO)2]PF6 (5), [Zn2(L3)(NCS)3] (6), [Zn2(L4)(AcO)2]C104 (7), [Zn2(L4)(AcO)(NCS)2] (8) and [Zn2(L4)(NCS)3] (9). The crystal structures of 1, 5·(DMF)0.5(2-PrOH)0.5, 7·CHCl3, 8·(2-PrOH) and 9·3CHCl3 have been determined. Complexes 1 and 5·(DMF)0.5(2-PrOH)0.5 have a di-μ-acetato-μ-phenolato-dizinc(II) core comprised of two square-pyramidal Zn centers. 7·CHCl3 has a similar dinuclear core, but it is comprised of one square-pyramidal Zn and one pseudo-octahedral Zn. 8·(2-PrOH) has a μ-acetato-μ-phenolato-dizinc(II) core with a unidentate thiocyanato-N group on each Zn. 9·3CHCl3 exists in two different crystals: one has a μ-thiocyanato-N-μ-phenolato-dizinc(II) core, whereas the other has a μ-phenolato-dizinc(II) core. The diacetato complexes, 1, 3, 5 and 7, are stable in solution. Hydrolytic activities of the complexes toward tris(p-nitrophenyl) phosphate (TNP) have been studied in aqueous DMF by means of UV-visible spectroscopic and 31P NMR methods. Complexes 1, 3 and 5 have an activity to hydrolyze TNP into bis(p-nitrophenyl) hydrogenphosphate (HBNP) in aqueous DMF. In contrast, 7 showed little hydrolytic activity toward TNP in aqueous DMF.
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U2 - 10.1246/bcsj.74.85
DO - 10.1246/bcsj.74.85
M3 - Article
AN - SCOPUS:0035126894
SN - 0009-2673
VL - 74
SP - 85
EP - 95
JO - Bulletin of the Chemical Society of Japan
JF - Bulletin of the Chemical Society of Japan
IS - 1
ER -