Synthesis and characterization of Ni(II) and Cu(II) complexes of 6-(β-(3,4-dimethoxyphenylethyl))cyclam (L1) and 6-(β-(3,4-dihydroxyphenylethyl))cyclam (H2L2) (cyclam=1,4,8,11-tetraazacyclotetradecane). X-ray crystal structures of [Cu(L1)Br2] and [Cu(H2(BrL2))Br]Br·H2O and metal ion templated formation of multinuclear macrocyclic complexes
摘要:
The synthesis of 6-(beta-(3,4-dimethoxyphenyl)ethyl)cyclam (L-1) and the corresponding Ni(II) and Cu(II) complexes is described. Demethylation of the complexes of L-1 was carried out with BBr3 and the corresponding Ni(II) and Cu(II) complexes of H2L2 (H2L2 = 6-(eta-(3,4-dihydroxyphenyl)ethyl)cyclam) have been isolated and characterized. Reaction of [Cu(L-1)Br-2] with Br-2 resulted in bromination of the phenyl group, to yield [Cu(BrL1)Br-2]. Demethylation of [Cu(BrL1)Br-2] yielded the corresponding bromo-catechol appended macrocyclic complex [Cu(H-2(BrL2))]Br-2, where H-2(BrL2) = 6-(beta-(6-bromo-3,4-dihydroxyphenyl)ethyl)cyclam. The crystal structures of [Cu(L-1)Br-2] and [Cu(H-2(BrL2))Br]BrH2O have been determined. In both complexes, the Cu(II) ion is within the macrocyclic cavity with an average Cu-N distance of (2.01 Angstrom). In [Cu(L-1)Br-2], the Cu(II) is pseudo-octahedral, with Cu-Br(1) = 2.9996(3) and Cu- Br(2)= 2.925(3) Angstrom whereas in [Cu(H-2(BrL2))Br]BrH2O the Cu(II) is square pyramidal with a Cu-Br distance of 2.904(2) Angstrom. Reaction of [M(H2L2)](2+) (M = Ni2+ and Cu2+) ions with Fe(III) in basic aqueous media led to the formation of the tetranuclear species [Fe(M(L-2)Br-2)(3)](3-), which has been monitored by UV-Vis and EPR spectroscopy. (C) 2000 Elsevier Science S.A. All rights reserved.
Synthesis and characterization of Ni(II) and Cu(II) complexes of 6-(β-(3,4-dimethoxyphenylethyl))cyclam (L1) and 6-(β-(3,4-dihydroxyphenylethyl))cyclam (H2L2) (cyclam=1,4,8,11-tetraazacyclotetradecane). X-ray crystal structures of [Cu(L1)Br2] and [Cu(H2(BrL2))Br]Br·H2O and metal ion templated formation of multinuclear macrocyclic complexes
摘要:
The synthesis of 6-(beta-(3,4-dimethoxyphenyl)ethyl)cyclam (L-1) and the corresponding Ni(II) and Cu(II) complexes is described. Demethylation of the complexes of L-1 was carried out with BBr3 and the corresponding Ni(II) and Cu(II) complexes of H2L2 (H2L2 = 6-(eta-(3,4-dihydroxyphenyl)ethyl)cyclam) have been isolated and characterized. Reaction of [Cu(L-1)Br-2] with Br-2 resulted in bromination of the phenyl group, to yield [Cu(BrL1)Br-2]. Demethylation of [Cu(BrL1)Br-2] yielded the corresponding bromo-catechol appended macrocyclic complex [Cu(H-2(BrL2))]Br-2, where H-2(BrL2) = 6-(beta-(6-bromo-3,4-dihydroxyphenyl)ethyl)cyclam. The crystal structures of [Cu(L-1)Br-2] and [Cu(H-2(BrL2))Br]BrH2O have been determined. In both complexes, the Cu(II) ion is within the macrocyclic cavity with an average Cu-N distance of (2.01 Angstrom). In [Cu(L-1)Br-2], the Cu(II) is pseudo-octahedral, with Cu-Br(1) = 2.9996(3) and Cu- Br(2)= 2.925(3) Angstrom whereas in [Cu(H-2(BrL2))Br]BrH2O the Cu(II) is square pyramidal with a Cu-Br distance of 2.904(2) Angstrom. Reaction of [M(H2L2)](2+) (M = Ni2+ and Cu2+) ions with Fe(III) in basic aqueous media led to the formation of the tetranuclear species [Fe(M(L-2)Br-2)(3)](3-), which has been monitored by UV-Vis and EPR spectroscopy. (C) 2000 Elsevier Science S.A. All rights reserved.