Developing redox switches that not only perform specific mechanical movements but also drive important chemical reactions is important but a great challenge.Herein,we report a redox pair of cobalt species(Co^(Ⅲ)/Co^(...Developing redox switches that not only perform specific mechanical movements but also drive important chemical reactions is important but a great challenge.Herein,we report a redox pair of cobalt species(Co^(Ⅲ)/Co^(Ⅱ))that switches through photo-dehydrogenation of alcohol and hydrogenation of azo-ligand.The cobalt species is equipped with a flexible azo-ligand containing two bulky planar substituents.A planar oxidated sate(Co^(Ⅲ)species)can be photo-reduced to a saddle-like reduced state(Co^(Ⅱ))with alcohol molecules as electron donors,and in turn the Co^(Ⅲ)species can be recovered with azo-ligand as oxidant under acidic surrounding.Both the redox states of the pair are isolated and characterized by single crystal X-ray diffraction.In the switching cycle,alcohol is oxidized to aldehyde by azo-ligand through proton coupled electron transfer and the cobalt complex acts as a redox catalyst.These results provide important insights into alcohol dehydrogenation catalyzed by redox complexes.展开更多
A new method for the synthesis of azo Schiff an base ligand in which the azo and azomethine groups are coordination sites was developed through a Schiff base precursor. The precursor, N-4-methoxybenzylidene-3-hydroxyp...A new method for the synthesis of azo Schiff an base ligand in which the azo and azomethine groups are coordination sites was developed through a Schiff base precursor. The precursor, N-4-methoxybenzylidene-3-hydroxyphenylamine （SB） derived from 3-aminophenol was regioselectively coupled with a diazonium ion para to the hydroxyl group of the amine component of the Schiff base. The para selectivity was controlled by the directing effect of the hydroxyl group. The ligand and its nickel（Ⅱ） complex were characterized by elemental analyses, IR and UV-Vis spectroscopy. The analytical and spectral data supported the mononuclear formulation of the complex with metal to ligand ratio （M ： L = 1 ： 2） and suggested a square planar geometry for the complex.展开更多
Two helical one-dimensional complexes [MnII(MeOH)4][MnIV(L·)2]·2MeOH (1) and [MnⅢ(salen)][MnⅢ(L)2] (2) (H2L = HON=C(Ph)N=NC_(6)H_(4)CO_(2)H) contain the noninnocent ligand [Mn(L·)2]2- and innocent low...Two helical one-dimensional complexes [MnII(MeOH)4][MnIV(L·)2]·2MeOH (1) and [MnⅢ(salen)][MnⅢ(L)2] (2) (H2L = HON=C(Ph)N=NC_(6)H_(4)CO_(2)H) contain the noninnocent ligand [Mn(L·)2]2- and innocent low-spin [Mn(L)2]-. Intrachain antiferromagnetic interaction between adjacent manganese ions via the syn-anti carboxylate bridges in complex 1. Alternate syn-anti and anti-anti carboxylate bridges have been found to transmit ferro-and antiferromagnetic coupling between high-spin and low-spin Mn(Ⅲ) ions in complex 2.展开更多
基金supported by the National Natural Science Foundation of China(Nos.21871262,21805275 and 21901242)the Natural Science Foundation of Fujian Province(No.2019J01130)the Recruitment Program of Global Youth Experts。
文摘Developing redox switches that not only perform specific mechanical movements but also drive important chemical reactions is important but a great challenge.Herein,we report a redox pair of cobalt species(Co^(Ⅲ)/Co^(Ⅱ))that switches through photo-dehydrogenation of alcohol and hydrogenation of azo-ligand.The cobalt species is equipped with a flexible azo-ligand containing two bulky planar substituents.A planar oxidated sate(Co^(Ⅲ)species)can be photo-reduced to a saddle-like reduced state(Co^(Ⅱ))with alcohol molecules as electron donors,and in turn the Co^(Ⅲ)species can be recovered with azo-ligand as oxidant under acidic surrounding.Both the redox states of the pair are isolated and characterized by single crystal X-ray diffraction.In the switching cycle,alcohol is oxidized to aldehyde by azo-ligand through proton coupled electron transfer and the cobalt complex acts as a redox catalyst.These results provide important insights into alcohol dehydrogenation catalyzed by redox complexes.
文摘A new method for the synthesis of azo Schiff an base ligand in which the azo and azomethine groups are coordination sites was developed through a Schiff base precursor. The precursor, N-4-methoxybenzylidene-3-hydroxyphenylamine （SB） derived from 3-aminophenol was regioselectively coupled with a diazonium ion para to the hydroxyl group of the amine component of the Schiff base. The para selectivity was controlled by the directing effect of the hydroxyl group. The ligand and its nickel（Ⅱ） complex were characterized by elemental analyses, IR and UV-Vis spectroscopy. The analytical and spectral data supported the mononuclear formulation of the complex with metal to ligand ratio （M ： L = 1 ： 2） and suggested a square planar geometry for the complex.
文摘Two helical one-dimensional complexes [MnII(MeOH)4][MnIV(L·)2]·2MeOH (1) and [MnⅢ(salen)][MnⅢ(L)2] (2) (H2L = HON=C(Ph)N=NC_(6)H_(4)CO_(2)H) contain the noninnocent ligand [Mn(L·)2]2- and innocent low-spin [Mn(L)2]-. Intrachain antiferromagnetic interaction between adjacent manganese ions via the syn-anti carboxylate bridges in complex 1. Alternate syn-anti and anti-anti carboxylate bridges have been found to transmit ferro-and antiferromagnetic coupling between high-spin and low-spin Mn(Ⅲ) ions in complex 2.
