赤铁矿是一种具有潜力的光电催化材料,已被广泛用于水氧化反应研究。在该反应中,赤铁矿受光激发后会在表面形成捕获态空穴,即高价铁氧物种(Fe^(IV)=O)。其受水分子的亲核进攻形成氧—氧键,且遵循质子耦合电荷转移机制,这一观点已得到动...赤铁矿是一种具有潜力的光电催化材料,已被广泛用于水氧化反应研究。在该反应中,赤铁矿受光激发后会在表面形成捕获态空穴,即高价铁氧物种(Fe^(IV)=O)。其受水分子的亲核进攻形成氧—氧键,且遵循质子耦合电荷转移机制,这一观点已得到动力学同位素效应、电化学阻抗谱以及原位光电化学红外光谱等实验证据的支持。在此基础上,受高价金属—氧物种诱导的氧原子转移(oxygen atom transfer,OAT)反应的启发,赤铁矿催化的有机相OAT反应取得了突破性进展,开辟了赤铁矿光电催化应用的新方向。这种高效的OAT机制被进一步拓展到一些典型的无机物(氨、亚硝酸盐等)氧化反应,为环境污染物的去除提供了新的思路。展开更多
A series of N-base appended corroles and their manganese complexes were synthesized and their binding constants with three different nitrogenous ligands, triethylamine, N-methylimidazole and pyridine, were evaluated b...A series of N-base appended corroles and their manganese complexes were synthesized and their binding constants with three different nitrogenous ligands, triethylamine, N-methylimidazole and pyridine, were evaluated by spectroscopy. Kinetic studies indicated that the presence of appended N- donor ligands may cause a significant enhancement of the rate of oxygen atom transfers （OAT） from （oxo）manganese（V） corrole to alkene, and the stronger axial ligand binding has impact on the rate of the oxidation reaction. Turnover frequency （TOF） for the catalytic oxidation of alkenes by appended manganese corroles varies with the following ligand order： acetamido 〈 pyridyl 〈 imidazolyl. The influence of the external axial ligands on the catalytic epoxidation was investigated by using appended acetamido manganese corrole as catalyst, with the results revealing that N-methylimidazole gave the best enhancement on the yields of total oxidation products among the investigated nitrogenous ligands.展开更多
The effects of axial ligand on the oxygen atom transfer(OAT)reaction from 5,10,15-tris(pentafluorophenyl)corrole((tpfc)MnVO)to dimethyl sulfide(DMS)have been investigated by density functional theory(DFT)calculations....The effects of axial ligand on the oxygen atom transfer(OAT)reaction from 5,10,15-tris(pentafluorophenyl)corrole((tpfc)MnVO)to dimethyl sulfide(DMS)have been investigated by density functional theory(DFT)calculations.Imidazole(Im),4-methylimidazole(4-MI)and pyridine(Py)were selected as the axial ligands.The results revealed that the axial ligand can form coordinate bond with(tpfc)MnVO in the transition state(TS)of the OAT reaction.The axial coordination favored charge transferring from(tpfc)MnVO to DMS,and weakened the Mn≡O bond in both singlet and triplet states.Furthermore,axial coordination can reduce the energy barrier of neutral(tpfc)MnVO from 23.62 kJ·mol^-1 to less than 3 kJ·mol^-1 in the triplet state,which is significantly lower than in the singlet state.This makes(tpfc)MnVO tend to direct the OAT reaction via triplet state pathway.On the other hand,the energy barriers of[(tpfc)MnVIO]+species from disproportionation pathway increased from 1.26 to 33.95 kJ·mol^-1 in a doublet state.This suggests axial ligands were conducive for direct(tpfc)MnVO OAT reaction pathway.展开更多
Pseudo-first order reaction rate constants of 5,10,15-tris（pentafluorophenyl）corrole Mn（V）-oxo （F_（15）CMn（V）-oxo）,5,15-bis（pentafluorophenyl）-10-（phenyl）corrole Mn（V）-oxo（F_（10）CMn（V）-oxo）,5,15- ...Pseudo-first order reaction rate constants of 5,10,15-tris（pentafluorophenyl）corrole Mn（V）-oxo （F_（15）CMn（V）-oxo）,5,15-bis（pentafluorophenyl）-10-（phenyl）corrole Mn（V）-oxo（F_（10）CMn（V）-oxo）,5,15- bis（phenyl）-10-（pentafluorophenyl）corrole Mn（V）-oxo（F_5CMn（V）-oxo） and 5,10,15-tris（phenyl）corrole Mn（V）-oxo（F_0CMn（V）-oxo） with a series of alkene substrates in different solvents were determined by UV-vis spectroscopy.The results indicated that the oxygen atom transfer pathway between Mn（V）-oxo corrole and alkene is solvent-dependent.展开更多
Our previous study on the kinetics for reactions of M<sub>3</sub>（CO）<sub>12</sub>（M=Fe, Ru, Os） on Me<sub>3</sub>NO in the presence of another entering ligand has shown that th...Our previous study on the kinetics for reactions of M<sub>3</sub>（CO）<sub>12</sub>（M=Fe, Ru, Os） on Me<sub>3</sub>NO in the presence of another entering ligand has shown that the rates of CO substitution of these metal clusters decrease in the order Fe】Ru】Os. It suggests that the order of reactivity of these metal carbonyls decreases with the decreasing tendency of展开更多
文摘赤铁矿是一种具有潜力的光电催化材料,已被广泛用于水氧化反应研究。在该反应中,赤铁矿受光激发后会在表面形成捕获态空穴,即高价铁氧物种(Fe^(IV)=O)。其受水分子的亲核进攻形成氧—氧键,且遵循质子耦合电荷转移机制,这一观点已得到动力学同位素效应、电化学阻抗谱以及原位光电化学红外光谱等实验证据的支持。在此基础上,受高价金属—氧物种诱导的氧原子转移(oxygen atom transfer,OAT)反应的启发,赤铁矿催化的有机相OAT反应取得了突破性进展,开辟了赤铁矿光电催化应用的新方向。这种高效的OAT机制被进一步拓展到一些典型的无机物(氨、亚硝酸盐等)氧化反应,为环境污染物的去除提供了新的思路。
基金supported by the National Natural Science Foundation of China(21972158)Joint Fund of the Yulin University and the Dalian National Laboratory for Clean Energy(2021017)+2 种基金Foundation of State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering(2021-K10)Natural Science Foundation of Shanxi Province(SQ2019006)Patent Conversion Foundation of Shanxi Province(202202093)。
基金supported by National Natural Science Foundation of China(Nos.21171057,21371059)Research Grant Councilof Hong Kong under project HKUST6182/99pArea of Excellence Scheme(No.AoE/P-10/01)
文摘A series of N-base appended corroles and their manganese complexes were synthesized and their binding constants with three different nitrogenous ligands, triethylamine, N-methylimidazole and pyridine, were evaluated by spectroscopy. Kinetic studies indicated that the presence of appended N- donor ligands may cause a significant enhancement of the rate of oxygen atom transfers （OAT） from （oxo）manganese（V） corrole to alkene, and the stronger axial ligand binding has impact on the rate of the oxidation reaction. Turnover frequency （TOF） for the catalytic oxidation of alkenes by appended manganese corroles varies with the following ligand order： acetamido 〈 pyridyl 〈 imidazolyl. The influence of the external axial ligands on the catalytic epoxidation was investigated by using appended acetamido manganese corrole as catalyst, with the results revealing that N-methylimidazole gave the best enhancement on the yields of total oxidation products among the investigated nitrogenous ligands.
基金supported by the National Natural Science Foundation of China(21275057,21671068)Natural Science Foundation of Guangdong Province(S2012010008763,2017A050506048)
文摘The effects of axial ligand on the oxygen atom transfer(OAT)reaction from 5,10,15-tris(pentafluorophenyl)corrole((tpfc)MnVO)to dimethyl sulfide(DMS)have been investigated by density functional theory(DFT)calculations.Imidazole(Im),4-methylimidazole(4-MI)and pyridine(Py)were selected as the axial ligands.The results revealed that the axial ligand can form coordinate bond with(tpfc)MnVO in the transition state(TS)of the OAT reaction.The axial coordination favored charge transferring from(tpfc)MnVO to DMS,and weakened the Mn≡O bond in both singlet and triplet states.Furthermore,axial coordination can reduce the energy barrier of neutral(tpfc)MnVO from 23.62 kJ·mol^-1 to less than 3 kJ·mol^-1 in the triplet state,which is significantly lower than in the singlet state.This makes(tpfc)MnVO tend to direct the OAT reaction via triplet state pathway.On the other hand,the energy barriers of[(tpfc)MnVIO]+species from disproportionation pathway increased from 1.26 to 33.95 kJ·mol^-1 in a doublet state.This suggests axial ligands were conducive for direct(tpfc)MnVO OAT reaction pathway.
基金The financial support from the National Natural Science Foundation of China(Nos.20971046 and 21171057)
文摘Pseudo-first order reaction rate constants of 5,10,15-tris（pentafluorophenyl）corrole Mn（V）-oxo （F_（15）CMn（V）-oxo）,5,15-bis（pentafluorophenyl）-10-（phenyl）corrole Mn（V）-oxo（F_（10）CMn（V）-oxo）,5,15- bis（phenyl）-10-（pentafluorophenyl）corrole Mn（V）-oxo（F_5CMn（V）-oxo） and 5,10,15-tris（phenyl）corrole Mn（V）-oxo（F_0CMn（V）-oxo） with a series of alkene substrates in different solvents were determined by UV-vis spectroscopy.The results indicated that the oxygen atom transfer pathway between Mn（V）-oxo corrole and alkene is solvent-dependent.
基金Project supported by the National Natural Science Foundation of China
文摘Our previous study on the kinetics for reactions of M<sub>3</sub>（CO）<sub>12</sub>（M=Fe, Ru, Os） on Me<sub>3</sub>NO in the presence of another entering ligand has shown that the rates of CO substitution of these metal clusters decrease in the order Fe】Ru】Os. It suggests that the order of reactivity of these metal carbonyls decreases with the decreasing tendency of
