以乙醇为溶剂、RhCl3.3H2O为铑源、三苯基膦(PPh3)为配体及甲醛为羰基源,在常压回流条件下一步法合成目标铑膦配合物HRh(CO)(PPh3)3,考察了不同氢源(H2、NaBH4和KOH)对铑膦配合物结构的影响.利用FT-IR、31P CP MAS NMR和XPS等对不同氢...以乙醇为溶剂、RhCl3.3H2O为铑源、三苯基膦(PPh3)为配体及甲醛为羰基源,在常压回流条件下一步法合成目标铑膦配合物HRh(CO)(PPh3)3,考察了不同氢源(H2、NaBH4和KOH)对铑膦配合物结构的影响.利用FT-IR、31P CP MAS NMR和XPS等对不同氢源条件下制备的铑膦配合物产物的结构进行表征.结果显示:以H2为氢源时,铑膦配合物产物主要为trans-RhCl(CO)(PPh3)2;以NaBH4为氢源时,产物为trans-RhCl(CO)(PPh3)2和HRh(CO)(PPh3)3的混合产物,同时甲醛溶液的滴加速度对产物的组成也有着重要影响,通过控制甲醛溶液的滴加速度可以有效抑制产物中trans-RhCl(CO)(PPh3)2的含量;以KOH为氢源时,产物为目标产物HRh(CO)(PPh3)3.展开更多
Eight metal cluster compounds have been synthesized from parent compound （μ3-CPh）Co3-（CO）9 and triphenylphosphine（arsine,stibine,bismuthine）. All the compounds were characterized by elemental analysis and IR sp...Eight metal cluster compounds have been synthesized from parent compound （μ3-CPh）Co3-（CO）9 and triphenylphosphine（arsine,stibine,bismuthine）. All the compounds were characterized by elemental analysis and IR spectrometry. They results showed that their catalytic activities for 1-butene hydroformylation and the yields of product both were higher than that of the parent compound in 97% and 20% more, respectively, at reaction conditions of 303.5 K, 0.392 MPa, and for 48 hours. The catalytic activities and the ratio of nor to iso by using PhCCo3（CO）7（APh3）m were increased with increase in the atomic numbers of element A（A=P,As,Sb,Bi）.展开更多
A new protocol that enables asymmetric hydroaminomethylation of styrenes to afford chiral amines has been developed. Catalysed by an Rh-phosphine species and a chiral phosphoric acid, styrenes are converted into β-ch...A new protocol that enables asymmetric hydroaminomethylation of styrenes to afford chiral amines has been developed. Catalysed by an Rh-phosphine species and a chiral phosphoric acid, styrenes are converted into β-chiral amines with good enantioselectivities under syngas in the presence of an amine and Hantzsch ester. The reaction involves two key steps, hydroformylation and reductive amination, with the former catalysed by the Rh species whilst the latter by the phosphoric acid.展开更多
Polyether-tailored phosphite modified rhodium complex formed in situ was highly active in the hydroformylation of oleyl alcohol in nonaqueous phosphite/heptane system where the phosphite acted both as the ligand and t...Polyether-tailored phosphite modified rhodium complex formed in situ was highly active in the hydroformylation of oleyl alcohol in nonaqueous phosphite/heptane system where the phosphite acted both as the ligand and the second phase. This catalyst was easily separated by simple decantation and can be used for five times with only a slight decrease in activity.展开更多
Hydroformylation of 1-dodecene was studied in a biphasic system using water-soluble rhodium complex [RhCl(CO)(TPPTS)2] as catalyst in the presence of cetyl trimethyl ammonium bromide as surfactant to enhance the react...Hydroformylation of 1-dodecene was studied in a biphasic system using water-soluble rhodium complex [RhCl(CO)(TPPTS)2] as catalyst in the presence of cetyl trimethyl ammonium bromide as surfactant to enhance the reaction rate. Efforts were devoted to improve the performance of hydroformylation by exploring reactor the reaction configuration which enhanced the mixing, dispersion and interphase mass transfer. Experiments were carried out in a 0.5L autoclave at the total pressure of 1.1MPa and temperature from 363K to 373K. Several surface aeration configurations were tested, and higher hydroformylation rate with higher normal/branched aldehyde ratio produced were achieved. The experience suggest that improved reactor configuration by taking reaction engineering, measures is beneficial to better process economy in alkene hydroformylation.展开更多
This paper studied the mechanism of the alkene insertion elementary step in the asymmetric hydroformylation(AHF)catalyzed by RhH(CO)2[(R,S)-Yanphos]using four alkene substrates(CH255CH–Ph,CH255CH–Ph–(p)–Me,CH255CH...This paper studied the mechanism of the alkene insertion elementary step in the asymmetric hydroformylation(AHF)catalyzed by RhH(CO)2[(R,S)-Yanphos]using four alkene substrates(CH255CH–Ph,CH255CH–Ph–(p)–Me,CH255CH–C(55O)OCH3and CH255CH–OC(55O)–Ph,abbreviated as A1–A4).Interestingly,the equatorial vertical coordination mode(A mode)with respect to the Rh center was found for A1 and A2 but not for A3 and A4,although the equatorial in-plane coordination mode(E mode)was found for A1–A4.The relative energy of the E mode of the h2-intermediates is lower than that of the A mode.In the alkene insertion step,Path 1 is more favorable than Path 2 for this system.As for A1 and A2,there could be a transformation between 2eq and 2ax.展开更多
Rhodium catalyzed hydroformylation of a-methylstyrene was investigated in the presence of monodentate phosphine ligands L1–L6. We found that the phosphine with good p-acceptability could efficiently improve the activ...Rhodium catalyzed hydroformylation of a-methylstyrene was investigated in the presence of monodentate phosphine ligands L1–L6. We found that the phosphine with good p-acceptability could efficiently improve the activity of the a-methylstyrene hydroformylation. The big steric hindrance of a-C in a-methylstyrene enhanced the regioselectivity towards the linear aldehyde, which resulted in3-phenylbutanal as the predominant product(>99.0%). When tris(N-pyrrolyl)phosphine(L1) modified Rh(acac)(CO)_2was employed as the catalyst, the TOF could reach up to 5786 h^(-1)in the a-methylstyrene hydroformylation at relatively mild conditions(110 8C, 6 MPa).展开更多
文摘以乙醇为溶剂、RhCl3.3H2O为铑源、三苯基膦(PPh3)为配体及甲醛为羰基源,在常压回流条件下一步法合成目标铑膦配合物HRh(CO)(PPh3)3,考察了不同氢源(H2、NaBH4和KOH)对铑膦配合物结构的影响.利用FT-IR、31P CP MAS NMR和XPS等对不同氢源条件下制备的铑膦配合物产物的结构进行表征.结果显示:以H2为氢源时,铑膦配合物产物主要为trans-RhCl(CO)(PPh3)2;以NaBH4为氢源时,产物为trans-RhCl(CO)(PPh3)2和HRh(CO)(PPh3)3的混合产物,同时甲醛溶液的滴加速度对产物的组成也有着重要影响,通过控制甲醛溶液的滴加速度可以有效抑制产物中trans-RhCl(CO)(PPh3)2的含量;以KOH为氢源时,产物为目标产物HRh(CO)(PPh3)3.
文摘Eight metal cluster compounds have been synthesized from parent compound （μ3-CPh）Co3-（CO）9 and triphenylphosphine（arsine,stibine,bismuthine）. All the compounds were characterized by elemental analysis and IR spectrometry. They results showed that their catalytic activities for 1-butene hydroformylation and the yields of product both were higher than that of the parent compound in 97% and 20% more, respectively, at reaction conditions of 303.5 K, 0.392 MPa, and for 48 hours. The catalytic activities and the ratio of nor to iso by using PhCCo3（CO）7（APh3）m were increased with increase in the atomic numbers of element A（A=P,As,Sb,Bi）.
文摘A new protocol that enables asymmetric hydroaminomethylation of styrenes to afford chiral amines has been developed. Catalysed by an Rh-phosphine species and a chiral phosphoric acid, styrenes are converted into β-chiral amines with good enantioselectivities under syngas in the presence of an amine and Hantzsch ester. The reaction involves two key steps, hydroformylation and reductive amination, with the former catalysed by the Rh species whilst the latter by the phosphoric acid.
基金The authors are grateful to the financial support from the National Natural Science Foundation of China(Grant No.29906001)
文摘Polyether-tailored phosphite modified rhodium complex formed in situ was highly active in the hydroformylation of oleyl alcohol in nonaqueous phosphite/heptane system where the phosphite acted both as the ligand and the second phase. This catalyst was easily separated by simple decantation and can be used for five times with only a slight decrease in activity.
基金the National Natural Science Foundation of China (No. 29792074) and SINOPEC.
文摘Hydroformylation of 1-dodecene was studied in a biphasic system using water-soluble rhodium complex [RhCl(CO)(TPPTS)2] as catalyst in the presence of cetyl trimethyl ammonium bromide as surfactant to enhance the reaction rate. Efforts were devoted to improve the performance of hydroformylation by exploring reactor the reaction configuration which enhanced the mixing, dispersion and interphase mass transfer. Experiments were carried out in a 0.5L autoclave at the total pressure of 1.1MPa and temperature from 363K to 373K. Several surface aeration configurations were tested, and higher hydroformylation rate with higher normal/branched aldehyde ratio produced were achieved. The experience suggest that improved reactor configuration by taking reaction engineering, measures is beneficial to better process economy in alkene hydroformylation.
基金in part supported by the National Natural Science Foundation of China (Nos. 21072018 and 21203006)
文摘This paper studied the mechanism of the alkene insertion elementary step in the asymmetric hydroformylation(AHF)catalyzed by RhH(CO)2[(R,S)-Yanphos]using four alkene substrates(CH255CH–Ph,CH255CH–Ph–(p)–Me,CH255CH–C(55O)OCH3and CH255CH–OC(55O)–Ph,abbreviated as A1–A4).Interestingly,the equatorial vertical coordination mode(A mode)with respect to the Rh center was found for A1 and A2 but not for A3 and A4,although the equatorial in-plane coordination mode(E mode)was found for A1–A4.The relative energy of the E mode of the h2-intermediates is lower than that of the A mode.In the alkene insertion step,Path 1 is more favorable than Path 2 for this system.As for A1 and A2,there could be a transformation between 2eq and 2ax.
基金financial support from the National Natural Science Foundation of China (No. 201202108)from the Opening Project of Key Laboratory of Green Chemistry of Sichuan Institutes of Higher Education (No. LZJ1402)from the Sichuan university outstanding scholar research fund (No. 2015SCU04A05)
文摘Rhodium catalyzed hydroformylation of a-methylstyrene was investigated in the presence of monodentate phosphine ligands L1–L6. We found that the phosphine with good p-acceptability could efficiently improve the activity of the a-methylstyrene hydroformylation. The big steric hindrance of a-C in a-methylstyrene enhanced the regioselectivity towards the linear aldehyde, which resulted in3-phenylbutanal as the predominant product(>99.0%). When tris(N-pyrrolyl)phosphine(L1) modified Rh(acac)(CO)_2was employed as the catalyst, the TOF could reach up to 5786 h^(-1)in the a-methylstyrene hydroformylation at relatively mild conditions(110 8C, 6 MPa).
