A series of novel cobalt carbonyl ionic liquids based on1,1,3,3‐tetra‐alkyl‐guanidine,such as[1,1‐dimethyl‐3,3‐diethylguanidinium][Co(CO)4](3a),[1,1‐dimethyl‐3,3‐dibutylguanidinium][Co(CO)4](3b),[1,1‐dimethy...A series of novel cobalt carbonyl ionic liquids based on1,1,3,3‐tetra‐alkyl‐guanidine,such as[1,1‐dimethyl‐3,3‐diethylguanidinium][Co(CO)4](3a),[1,1‐dimethyl‐3,3‐dibutylguanidinium][Co(CO)4](3b),[1,1‐dimethyl‐3,3‐tetramethyleneguanidinium][Co(CO)4](3c),and[1,1‐dimethyl‐3,3‐pentamethyleneguanidinium][Co(CO)4](3d),were synthesized in good yields and were also characterized using infrared spectroscopy,ultraviolet‐visible spectroscopy,1H nuclear magnetic resonance(NMR)spectroscopy,13C NMR spectroscopy,high‐resolution mass spectrometry,differential scanning calorimetry,and thermogravimetric analysis.The four compounds exhibited high thermal and chemical stability.In addition,the catalytic performance of these compounds was investigated in the carbonylation of epoxides,with3a exhibiting the best catalytic activity without the aid of a base as the additive.The catalyst could be reused at least six times without significant decreases of the selectivity or conversion rate.Moreover,the catalyst system exhibited good tolerance with terminal epoxides bearing alkyl,alkenyl,aryl,alkoxy,and chloromethyl functional groups.展开更多
Ab initio method, under the effective core potential(ECP) approximation at HF/LANL2DZ level, has been employed to study the reaction mechanism of the carbonyl insertion of olefin hydroformylation catalyzed by a carbo...Ab initio method, under the effective core potential(ECP) approximation at HF/LANL2DZ level, has been employed to study the reaction mechanism of the carbonyl insertion of olefin hydroformylation catalyzed by a carbonyl cobalt HCo(CO)_3. The two reaction paths have been discussed. The calculated potential energy barriers for the carbonyl migration and the ethyl group migration are 105. 0 kJ/mol and 39. 17 kJ/mol, respectively. The results indicate that the reaction path via ethyl migration is more energetically favorable than that via carbonyl insertion.展开更多
The photopromoted carbonylation of chloroalkanes with carbon monoxide catalyzed by cobalt compounds[Co（OAc）2,CoCl2] in the presence of KI was carried out under ambient conditions.The results revealed that the cataly...The photopromoted carbonylation of chloroalkanes with carbon monoxide catalyzed by cobalt compounds[Co（OAc）2,CoCl2] in the presence of KI was carried out under ambient conditions.The results revealed that the catalytic activity of Co（OAc）2 was higher than that of CoCl2.A basic additive NaOAc was beneficial to the reaction.Interestingly,with NaOAc as an additive, Co（OAc）2 and CoCl2 exhibited similar catalytic activity.Preliminary work showed that the role of iodide ion was initially to form active iodoalkanes via substituting chloride ion in chloroalkanes in situ,and then,the carbonylation of iodoalkanes proceeded under irradiation.展开更多
The reaction of octacarbonyldicobalt and dipropargyl malonate afforded the two expected compounds [CH 2(CO 2CH 2C 2H\|μ) 2][Co 2(CO) 6] 2 1 and [HC 2CH 2O(O)C^CH 2CO 2CH 2C 2H\|μ][Co 2(CO) 6)] 2. Bot...The reaction of octacarbonyldicobalt and dipropargyl malonate afforded the two expected compounds [CH 2(CO 2CH 2C 2H\|μ) 2][Co 2(CO) 6] 2 1 and [HC 2CH 2O(O)C^CH 2CO 2CH 2C 2H\|μ][Co 2(CO) 6)] 2. Both 1 and 2 were characterized by elemental analysis, IR and NMR. The molecular structure of 1 was determined by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with the following crystallographic parameters~: a=7.7492(15), b=12.925(3), c=14.366(3) , α=81.92(3), β=77.94(3), γ=89.48(3)°, V=1392.9(5) 3, Z= 2, M r=751.99, D c=1.793 g/cm 3, F(000)=740, μ(Mo-Kα)=24.13 cm -1 and final R=0.0880 for 5421 observations with I>2σ(I).展开更多
A novel method of preparing dimethyl malonate by carbonylation of methyl chloroacetate catalyzed by Na[Co(CO)(4)] was proposed. Na[Co(CO)(4)] was synthesized in situ in the presence of Na2S2O3 and iron powder. The eff...A novel method of preparing dimethyl malonate by carbonylation of methyl chloroacetate catalyzed by Na[Co(CO)(4)] was proposed. Na[Co(CO)(4)] was synthesized in situ in the presence of Na2S2O3 and iron powder. The effects of some reaction parameters such as temperature. CO pressure and the concentrations of catalyst on the yields of dimethyl malonate were discussed. The kinetic data were studied and a possible reaction mechanism was proposed.展开更多
Cobalt-phthalocyanine/iron nanocomposite particles have been obtained using method of composite in situ, with the mixture of carbonyl iron and solution of cobalt ( Ⅱ ) - phthalocyanine (Co-Pc) ultrasonic dispersing i...Cobalt-phthalocyanine/iron nanocomposite particles have been obtained using method of composite in situ, with the mixture of carbonyl iron and solution of cobalt ( Ⅱ ) - phthalocyanine (Co-Pc) ultrasonic dispersing in N,N-dimethyl-formamide (DMF). Structure characterization of their inner and surface have relation with method of carbonyl iron joined in the mixture, contents of carbonyl iron and Co-Pc in the mixture of Co-Pc ultrasonic dispersing in DMF. With a method of composite in situ controlling reasonable experiment condition, it can be obtained that cobalt-phthalocyanine/iron nanocomposite particles has completely been covered with Co-Pc, they had structure of Chinese gooseberry in inner and mere made up of almost regular spherical shape and the average diameter is 1. 4 μm.展开更多
The photopromoted carbonylation of bromobenzene with carbon monoxide catalyzed by inexpensive commercially available cobalt salts [Co（OAc）2, COCl2] was carried out under ambient conditions. The results revealed that...The photopromoted carbonylation of bromobenzene with carbon monoxide catalyzed by inexpensive commercially available cobalt salts [Co（OAc）2, COCl2] was carried out under ambient conditions. The results revealed that methyl benzoate was produced in the presence of basic additives （CH3ONa, NaOAc or （n-C4H9）3N）. The catalytic activity of Co（OAc）2 was higher than that of COCl2. Furthermore, the activity of the carbonylation was greatly improved by addition of acetophenone, e.g. both the yield and selectivity of the ester were increased from 47% to 91% with Co（OAc）2 as catalyst and CH3ONa as additive, while the yield of byproduct benzene from hydrodehalogenation of bromobenzene decreased from 32% to 8%.展开更多
Water-gas shift reaction catalyst at lower temperature （200-400 ℃） may improve the conversion of carbon monoxide. But carbonyl sulfide was found to be present over the sulfided cobaltmolybdenum/alumina catalyst for...Water-gas shift reaction catalyst at lower temperature （200-400 ℃） may improve the conversion of carbon monoxide. But carbonyl sulfide was found to be present over the sulfided cobaltmolybdenum/alumina catalyst for water-gas shift reaction. The influences of temperature, space velocity, and gas components on the formation of carbonyl sulfide over sulfided cobalt-molybdenum/alumina catalyst B303Q at 200-400 ℃ were studied in a tubular fixed-bed quartz-glass reactor under simulated water-gas shift conditions. The experimental results showed that the yield of carbonyl sulfide over B303Q catalyst reached a maximum at 220 ℃ with the increase in temperature, sharply decreased with the increase in space velocity and the content of water vapor, increased with the increase in the content of carbon monoxide and carbon dioxide, and its yield increased and then reached a stable value with the increase in the content of hydrogen and hydrogen sulfide. The formation mechanism of carbonyl sulfide over B303Q catalyst at 200-400 ℃ was discussed on the basis of how these factors influence the formation of COS. The yield of carbonyl sulfide over B303Q catalyst at 200-400 ℃ was the combined result of two reactions, that is, COS was first produced by the reaction of carbon monoxide with hydrogen sulfide, and then the as-produced COS was converted to hydrogen sulfide and carbon dioxide by hydrolysis. The mechanism of COS formation is assumed as follows： sulfur atoms in the Co9Ss-MoS2/Al2O3 crystal lattice were easily removed and formed carbonyl sulfide with CO, and then hydrogen sulfide in the water-gas shift gas reacted with the crystal lattice oxygen atoms in CoO-MoOa/Al2O3 to form Co9S8-MoS2/Al2O3. This mechanism for the formation of COS over water-gas shift catalyst B303Q is in accordance with the Mars-Van Krevelen＇s redox mechanism over metal sulfide.展开更多
A new technology was put forward to deal with the carbonyl slag at low acidity and low oxygen pressure in the kettle. With the orthogonal experiments for analyzing the sequence of four factors and some single factor e...A new technology was put forward to deal with the carbonyl slag at low acidity and low oxygen pressure in the kettle. With the orthogonal experiments for analyzing the sequence of four factors and some single factor experiments for the best conditions. The best conditions are used for extracting nickel, cobalt and copper and enriching precious metals: the cupric ion concentration is 5 g/L; and pH=6; the sulfur coefficient is 1.4; the oxygen pressure is 0.08 MPa; the time bubbling oxygen is 20 min; the ratio of liquid to solid is 8:1; the leaching time is 2 h; the heating time is 2.5 h. The leaching rates of nickel and cobalt are more than 98% and that of copper is above 97%. Nickel and cobalt can be separated efficiently from copper and precious metals from the carbonyl slag. Moreover, its leaching liquor has less copper. Nickel and cobalt can be reclaimed only once. During the whole process, the leaching rates of Au and Ag are more than 99.9%, while other precious metals are still in the residue without any loss.展开更多
Cobalt Phthalocyanine/Iron (CoPc/Fe) nanocomposite particles were prepared using mehods of organic inorganic composite in situ with cobalt phthalocyanine(CoPc) and carbonyl iron. The structure of composite particles w...Cobalt Phthalocyanine/Iron (CoPc/Fe) nanocomposite particles were prepared using mehods of organic inorganic composite in situ with cobalt phthalocyanine(CoPc) and carbonyl iron. The structure of composite particles was characterized by density measurement, XRD, SEM and TEM. The results show that CoPc/Fe nanocomposites with density of 3.99 g· cm－ 3 were almost micro sized regular spheroids consisting ofα Fe nanoparticles with average diameter 20 nm in inner and CoPc layer on the surface of spheroids. Further, microwave electromagnetic parameters of CoPc/Fe nanocomposite particles was measured, and the dependences ofε r andμ r on frequency were investigated. Compared with carbonyl iron powders, the composite permittivityε r significantly decreases while composite permabilityμ r changes slightly, which may increases the width of microwave absorbing frequency.展开更多
The reaction of Co 2(CO) 8 with organic hetrocyclic dithiophosphinate,SP(Fc)(S)N(C 6H 5)NC(Me),gave three cobalt carbonyl cluster derivatives,Co 4(CO) 8(μ CO) 2(μ 4 S)[μ 4 P(Fc)]f,Co 4(CO) 10 (μ 3 S)[μ η 2 P(Fc)...The reaction of Co 2(CO) 8 with organic hetrocyclic dithiophosphinate,SP(Fc)(S)N(C 6H 5)NC(Me),gave three cobalt carbonyl cluster derivatives,Co 4(CO) 8(μ CO) 2(μ 4 S)[μ 4 P(Fc)]f,Co 4(CO) 10 (μ 3 S)[μ η 2 P(Fc)N(C 6H 5)NC(Me)] and Co 2(CO) 5[μ η 2 P(Fc)N(C 6H 5)NC(Me)].These clusters were characterized by elementary analysis,IR, 1HNMR and MS spectroscopy.During the reaction,the precursor was cleaved in its P=S,P S,P N and C S bonds,respectively,to give the fragments as ligands as listed above that coordinated to Co atoms to form the new cluster molecules.展开更多
基金supported by the National Natural Science Foundation of China(21373248,21673260,21133011)~~
文摘A series of novel cobalt carbonyl ionic liquids based on1,1,3,3‐tetra‐alkyl‐guanidine,such as[1,1‐dimethyl‐3,3‐diethylguanidinium][Co(CO)4](3a),[1,1‐dimethyl‐3,3‐dibutylguanidinium][Co(CO)4](3b),[1,1‐dimethyl‐3,3‐tetramethyleneguanidinium][Co(CO)4](3c),and[1,1‐dimethyl‐3,3‐pentamethyleneguanidinium][Co(CO)4](3d),were synthesized in good yields and were also characterized using infrared spectroscopy,ultraviolet‐visible spectroscopy,1H nuclear magnetic resonance(NMR)spectroscopy,13C NMR spectroscopy,high‐resolution mass spectrometry,differential scanning calorimetry,and thermogravimetric analysis.The four compounds exhibited high thermal and chemical stability.In addition,the catalytic performance of these compounds was investigated in the carbonylation of epoxides,with3a exhibiting the best catalytic activity without the aid of a base as the additive.The catalyst could be reused at least six times without significant decreases of the selectivity or conversion rate.Moreover,the catalyst system exhibited good tolerance with terminal epoxides bearing alkyl,alkenyl,aryl,alkoxy,and chloromethyl functional groups.
文摘Ab initio method, under the effective core potential(ECP) approximation at HF/LANL2DZ level, has been employed to study the reaction mechanism of the carbonyl insertion of olefin hydroformylation catalyzed by a carbonyl cobalt HCo(CO)_3. The two reaction paths have been discussed. The calculated potential energy barriers for the carbonyl migration and the ethyl group migration are 105. 0 kJ/mol and 39. 17 kJ/mol, respectively. The results indicate that the reaction path via ethyl migration is more energetically favorable than that via carbonyl insertion.
文摘The photopromoted carbonylation of chloroalkanes with carbon monoxide catalyzed by cobalt compounds[Co（OAc）2,CoCl2] in the presence of KI was carried out under ambient conditions.The results revealed that the catalytic activity of Co（OAc）2 was higher than that of CoCl2.A basic additive NaOAc was beneficial to the reaction.Interestingly,with NaOAc as an additive, Co（OAc）2 and CoCl2 exhibited similar catalytic activity.Preliminary work showed that the role of iodide ion was initially to form active iodoalkanes via substituting chloride ion in chloroalkanes in situ,and then,the carbonylation of iodoalkanes proceeded under irradiation.
文摘The reaction of octacarbonyldicobalt and dipropargyl malonate afforded the two expected compounds [CH 2(CO 2CH 2C 2H\|μ) 2][Co 2(CO) 6] 2 1 and [HC 2CH 2O(O)C^CH 2CO 2CH 2C 2H\|μ][Co 2(CO) 6)] 2. Both 1 and 2 were characterized by elemental analysis, IR and NMR. The molecular structure of 1 was determined by single-crystal X-ray diffraction. The crystal belongs to the triclinic system, space group P1 with the following crystallographic parameters~: a=7.7492(15), b=12.925(3), c=14.366(3) , α=81.92(3), β=77.94(3), γ=89.48(3)°, V=1392.9(5) 3, Z= 2, M r=751.99, D c=1.793 g/cm 3, F(000)=740, μ(Mo-Kα)=24.13 cm -1 and final R=0.0880 for 5421 observations with I>2σ(I).
文摘A novel method of preparing dimethyl malonate by carbonylation of methyl chloroacetate catalyzed by Na[Co(CO)(4)] was proposed. Na[Co(CO)(4)] was synthesized in situ in the presence of Na2S2O3 and iron powder. The effects of some reaction parameters such as temperature. CO pressure and the concentrations of catalyst on the yields of dimethyl malonate were discussed. The kinetic data were studied and a possible reaction mechanism was proposed.
基金Funded by Chinese National Natural Science Foundation (No. 29904005), Key Foundation (No. 50038010) and Open Foundation from State Key Lab.of Advanced Technology for Materials Synthesis and Processing.
文摘Cobalt-phthalocyanine/iron nanocomposite particles have been obtained using method of composite in situ, with the mixture of carbonyl iron and solution of cobalt ( Ⅱ ) - phthalocyanine (Co-Pc) ultrasonic dispersing in N,N-dimethyl-formamide (DMF). Structure characterization of their inner and surface have relation with method of carbonyl iron joined in the mixture, contents of carbonyl iron and Co-Pc in the mixture of Co-Pc ultrasonic dispersing in DMF. With a method of composite in situ controlling reasonable experiment condition, it can be obtained that cobalt-phthalocyanine/iron nanocomposite particles has completely been covered with Co-Pc, they had structure of Chinese gooseberry in inner and mere made up of almost regular spherical shape and the average diameter is 1. 4 μm.
基金the Science and Technology Research Project for University of Liaoning Province(No.20060038)for the generous financial support.
文摘The photopromoted carbonylation of bromobenzene with carbon monoxide catalyzed by inexpensive commercially available cobalt salts [Co（OAc）2, COCl2] was carried out under ambient conditions. The results revealed that methyl benzoate was produced in the presence of basic additives （CH3ONa, NaOAc or （n-C4H9）3N）. The catalytic activity of Co（OAc）2 was higher than that of COCl2. Furthermore, the activity of the carbonylation was greatly improved by addition of acetophenone, e.g. both the yield and selectivity of the ester were increased from 47% to 91% with Co（OAc）2 as catalyst and CH3ONa as additive, while the yield of byproduct benzene from hydrodehalogenation of bromobenzene decreased from 32% to 8%.
基金the National Basic Research Program of China (No.2005CB221203)
文摘Water-gas shift reaction catalyst at lower temperature （200-400 ℃） may improve the conversion of carbon monoxide. But carbonyl sulfide was found to be present over the sulfided cobaltmolybdenum/alumina catalyst for water-gas shift reaction. The influences of temperature, space velocity, and gas components on the formation of carbonyl sulfide over sulfided cobalt-molybdenum/alumina catalyst B303Q at 200-400 ℃ were studied in a tubular fixed-bed quartz-glass reactor under simulated water-gas shift conditions. The experimental results showed that the yield of carbonyl sulfide over B303Q catalyst reached a maximum at 220 ℃ with the increase in temperature, sharply decreased with the increase in space velocity and the content of water vapor, increased with the increase in the content of carbon monoxide and carbon dioxide, and its yield increased and then reached a stable value with the increase in the content of hydrogen and hydrogen sulfide. The formation mechanism of carbonyl sulfide over B303Q catalyst at 200-400 ℃ was discussed on the basis of how these factors influence the formation of COS. The yield of carbonyl sulfide over B303Q catalyst at 200-400 ℃ was the combined result of two reactions, that is, COS was first produced by the reaction of carbon monoxide with hydrogen sulfide, and then the as-produced COS was converted to hydrogen sulfide and carbon dioxide by hydrolysis. The mechanism of COS formation is assumed as follows： sulfur atoms in the Co9Ss-MoS2/Al2O3 crystal lattice were easily removed and formed carbonyl sulfide with CO, and then hydrogen sulfide in the water-gas shift gas reacted with the crystal lattice oxygen atoms in CoO-MoOa/Al2O3 to form Co9S8-MoS2/Al2O3. This mechanism for the formation of COS over water-gas shift catalyst B303Q is in accordance with the Mars-Van Krevelen＇s redox mechanism over metal sulfide.
文摘A new technology was put forward to deal with the carbonyl slag at low acidity and low oxygen pressure in the kettle. With the orthogonal experiments for analyzing the sequence of four factors and some single factor experiments for the best conditions. The best conditions are used for extracting nickel, cobalt and copper and enriching precious metals: the cupric ion concentration is 5 g/L; and pH=6; the sulfur coefficient is 1.4; the oxygen pressure is 0.08 MPa; the time bubbling oxygen is 20 min; the ratio of liquid to solid is 8:1; the leaching time is 2 h; the heating time is 2.5 h. The leaching rates of nickel and cobalt are more than 98% and that of copper is above 97%. Nickel and cobalt can be separated efficiently from copper and precious metals from the carbonyl slag. Moreover, its leaching liquor has less copper. Nickel and cobalt can be reclaimed only once. During the whole process, the leaching rates of Au and Ag are more than 99.9%, while other precious metals are still in the residue without any loss.
文摘Cobalt Phthalocyanine/Iron (CoPc/Fe) nanocomposite particles were prepared using mehods of organic inorganic composite in situ with cobalt phthalocyanine(CoPc) and carbonyl iron. The structure of composite particles was characterized by density measurement, XRD, SEM and TEM. The results show that CoPc/Fe nanocomposites with density of 3.99 g· cm－ 3 were almost micro sized regular spheroids consisting ofα Fe nanoparticles with average diameter 20 nm in inner and CoPc layer on the surface of spheroids. Further, microwave electromagnetic parameters of CoPc/Fe nanocomposite particles was measured, and the dependences ofε r andμ r on frequency were investigated. Compared with carbonyl iron powders, the composite permittivityε r significantly decreases while composite permabilityμ r changes slightly, which may increases the width of microwave absorbing frequency.
文摘The reaction of Co 2(CO) 8 with organic hetrocyclic dithiophosphinate,SP(Fc)(S)N(C 6H 5)NC(Me),gave three cobalt carbonyl cluster derivatives,Co 4(CO) 8(μ CO) 2(μ 4 S)[μ 4 P(Fc)]f,Co 4(CO) 10 (μ 3 S)[μ η 2 P(Fc)N(C 6H 5)NC(Me)] and Co 2(CO) 5[μ η 2 P(Fc)N(C 6H 5)NC(Me)].These clusters were characterized by elementary analysis,IR, 1HNMR and MS spectroscopy.During the reaction,the precursor was cleaved in its P=S,P S,P N and C S bonds,respectively,to give the fragments as ligands as listed above that coordinated to Co atoms to form the new cluster molecules.
