Sulfur was typically regarded as a poison to precious metal complex catalysts in hydroformylation of olefins.However,the combination of sulfur and phosphine may present an intriguing interaction with heterogeneous mon...Sulfur was typically regarded as a poison to precious metal complex catalysts in hydroformylation of olefins.However,the combination of sulfur and phosphine may present an intriguing interaction with heterogeneous mononuclear complex due to the difference of their electronegativities,and coordination capabilities.Herein,we report a novel sulfur-phosphine co-coordinated heterogeneous Rh mononuclear complex catalyst(Rh_(1)/POPs-PPh_(3)&S),which exhibits an unexpected 1.5–2.0 times catalytic activity for hydroformylation of olefins(C_(3)=,C_(5)=–C_(8)=),in comparison with the solely phosphine-coordinated Rh mononuclear complex catalyst(Rh_(1)/POPs-PPh_(3)).In contrast,sulfur coordination alone leads to severe sulfur poisoning with significantly inhibited catalytic performance.Experimental and theoretical analyses reveal that phosphine coordination promotes catalytic activity via its strong electron-donating ability,while sulfur occupies a coordination site and reduces the electronic density of Rh ions.The synergistical coordination of sulfur and phosphine optimizes the electronic density of active Rh ions and decreases the energy barrier of the rate-determining step of olefin insertion,thus enhancing the hydroformylation activity,regioselectivity and stability of Rh_(1)/POPs-PPh_(3)&S.展开更多
Fullerene n propylamine platinum,rhodium complex have been prepared from C 60 via amination with n propylamine, then reacting respectively with potassium chloroplatinite or rhodium chloride. The two nob...Fullerene n propylamine platinum,rhodium complex have been prepared from C 60 via amination with n propylamine, then reacting respectively with potassium chloroplatinite or rhodium chloride. The two noble metal complexes can effectively catalyze hydrosilylation of olefins with triethoxysilane. The Pt complex exhibits high regioselectivty for styrene, nearly 100% branched product is obtained.展开更多
MCM 41 molecular sieve supported Rh PPh 3 catalysts were prepared by the in situ assembling of the metal complex from smaller moieties of Rh(acac)(CO) 2 and ligand of PPh 3. The resulted vip/host materials(Rh PPh 3/...MCM 41 molecular sieve supported Rh PPh 3 catalysts were prepared by the in situ assembling of the metal complex from smaller moieties of Rh(acac)(CO) 2 and ligand of PPh 3. The resulted vip/host materials(Rh PPh 3/MCM 41) were characterized by X ray powder diffraction, FTIR and 31 P( 1H) NMR, and served as catalysts for propene hydroformylation. The results showed negligible change in MCM 41 framework after propene hydroformylation at 393 K. Higher hydroformylation activities were obtained on Rh PPh 3/MCM 41 catalysts compared to that on Rh PPh 3/SiO 2.展开更多
A new complex [Rh（COD）（2,2＇-bipy）]·[Rh（COD）Cl2]（COD = 1,5-cyclooctadiene, 2,2＇-bipy = 2,2＇-bipyridine） has been synthesized and characterized by elemental analyses, NMR and single-crystal X-ray diffrac...A new complex [Rh（COD）（2,2＇-bipy）]·[Rh（COD）Cl2]（COD = 1,5-cyclooctadiene, 2,2＇-bipy = 2,2＇-bipyridine） has been synthesized and characterized by elemental analyses, NMR and single-crystal X-ray diffraction. The complex crystallizes in triclinic system, space group P1 with a = 7.4782（14）, b = 10.1400（11）, c = 16.6982（14） , α = 103.494（11）, β = 91.996（13）, γ = 103.829（12）o, C26H32Cl2N2Rh2, Mr = 649.26, V = 1190.0（3）3, Dc = 1.812 g/cm3, Z = 2, F（000） = 652, μ（Mo Kα） = 1.629 mm-1, R = 0.0286 and w R = 0.0463 for 3718 observed reflections（I 2σ（I））. The complex was linked to form 1D chains by hydrogen bonding interaction（C–H···Cl）, and further to construct a 2D layer structure by π···π stacking interactions between the pyridine rings of 2,2＇-bipy ligands. The hydroformylation catalyzed by the title complex was also studied.展开更多
Metal complexes with excellent nonlinear optical（NLO） properties have attracted considerable attention. The geometry structure, electronic spectra and NLO properties of 2,2？-bidipyrrins（L） and mono-and bimetal Ir...Metal complexes with excellent nonlinear optical（NLO） properties have attracted considerable attention. The geometry structure, electronic spectra and NLO properties of 2,2？-bidipyrrins（L） and mono-and bimetal Ir（I）/Rh（I）–L complexes have been investigated by density functional theory method. Our calculations revealed that L with planar configuration shows the largest first hyperpolarizability value, which is 2.2 to 5.5 times larger than that of others. It is attributed to the single direction of intramolecular charge transfer. When metal ions were embedded in ligands, the first hyperpolarizability values of mono-and bimetal Ir/Rh（I）–L complexes were smaller than that of L, and that of bimetal Ir/Rh（I）–L complexes were smaller than the corresponding monometallic Ir/Rh（I）–L. This is caused by the intramolecular charge transfer from multiple directions as well as the amount of charge transfer. On the other hand, on increasing the number of metal ions, the charge transfer in the opposite direction cancels each other more obviously. Our work would provide some theoretical reference for the second-order NLO responses of mono-and bimetal complexes.展开更多
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
Rhodium catalyzed hydroformylation of α-methylstyrene was investigated in the presence of monodentate phosphine ligands L1-L6. We found that the phosphine with good n-acceptability could efficiently improve the activ...Rhodium catalyzed hydroformylation of α-methylstyrene was investigated in the presence of monodentate phosphine ligands L1-L6. We found that the phosphine with good n-acceptability could efficiently improve the activity of the α-methylstyrene hydroformylation. The big steric hindrance ofα-C in α-methylstyrene enhanced the regioselectivity towards the linear aldehyde, which resulted in 3-phenylbutanal as the predominant product （〉99.0%）. When tris（N-pyrrolyl）phosphine （L1） modified Rh（acac）（CO）2 was employed as the catalyst, the TOF could reach up to 5786 h 1 in the α-methylstyrene hvdroformvlation at relatively mild conditions （110 ℃, 6 MPa）.展开更多
文摘Sulfur was typically regarded as a poison to precious metal complex catalysts in hydroformylation of olefins.However,the combination of sulfur and phosphine may present an intriguing interaction with heterogeneous mononuclear complex due to the difference of their electronegativities,and coordination capabilities.Herein,we report a novel sulfur-phosphine co-coordinated heterogeneous Rh mononuclear complex catalyst(Rh_(1)/POPs-PPh_(3)&S),which exhibits an unexpected 1.5–2.0 times catalytic activity for hydroformylation of olefins(C_(3)=,C_(5)=–C_(8)=),in comparison with the solely phosphine-coordinated Rh mononuclear complex catalyst(Rh_(1)/POPs-PPh_(3)).In contrast,sulfur coordination alone leads to severe sulfur poisoning with significantly inhibited catalytic performance.Experimental and theoretical analyses reveal that phosphine coordination promotes catalytic activity via its strong electron-donating ability,while sulfur occupies a coordination site and reduces the electronic density of Rh ions.The synergistical coordination of sulfur and phosphine optimizes the electronic density of active Rh ions and decreases the energy barrier of the rate-determining step of olefin insertion,thus enhancing the hydroformylation activity,regioselectivity and stability of Rh_(1)/POPs-PPh_(3)&S.
文摘Fullerene n propylamine platinum,rhodium complex have been prepared from C 60 via amination with n propylamine, then reacting respectively with potassium chloroplatinite or rhodium chloride. The two noble metal complexes can effectively catalyze hydrosilylation of olefins with triethoxysilane. The Pt complex exhibits high regioselectivty for styrene, nearly 100% branched product is obtained.
基金Supported by the National Natural Science Foundation of China(Nos.2 98730 372 0 0 2 30 0 1and2 0 0 2 10 0 2 ) State KeyProject for Fundamental Research(No.G2 0 0 0 0 4 80 8) and the Ministry of Education of China
文摘MCM 41 molecular sieve supported Rh PPh 3 catalysts were prepared by the in situ assembling of the metal complex from smaller moieties of Rh(acac)(CO) 2 and ligand of PPh 3. The resulted vip/host materials(Rh PPh 3/MCM 41) were characterized by X ray powder diffraction, FTIR and 31 P( 1H) NMR, and served as catalysts for propene hydroformylation. The results showed negligible change in MCM 41 framework after propene hydroformylation at 393 K. Higher hydroformylation activities were obtained on Rh PPh 3/MCM 41 catalysts compared to that on Rh PPh 3/SiO 2.
基金Supported by the National Natural Science Foundation of China(Nos.2126102021361022)+2 种基金the Scientific and Technological Landing Project of Higher Education of Jiangxi Province(No.KJLD12094)the College Students’ Innovative Education Program of Jiangxi Provincethe Leading Talent Training Plan of "Xinjiang 866 Engineering Excellence"of Shangrao city
文摘A new complex [Rh（COD）（2,2＇-bipy）]·[Rh（COD）Cl2]（COD = 1,5-cyclooctadiene, 2,2＇-bipy = 2,2＇-bipyridine） has been synthesized and characterized by elemental analyses, NMR and single-crystal X-ray diffraction. The complex crystallizes in triclinic system, space group P1 with a = 7.4782（14）, b = 10.1400（11）, c = 16.6982（14） , α = 103.494（11）, β = 91.996（13）, γ = 103.829（12）o, C26H32Cl2N2Rh2, Mr = 649.26, V = 1190.0（3）3, Dc = 1.812 g/cm3, Z = 2, F（000） = 652, μ（Mo Kα） = 1.629 mm-1, R = 0.0286 and w R = 0.0463 for 3718 observed reflections（I 2σ（I））. The complex was linked to form 1D chains by hydrogen bonding interaction（C–H···Cl）, and further to construct a 2D layer structure by π···π stacking interactions between the pyridine rings of 2,2＇-bipy ligands. The hydroformylation catalyzed by the title complex was also studied.
基金Supported by the National Natural Science Foundation of China(No.21173035)the “12th Five-Year” Science and Technology Research Project of the Education Department of Jilin Province([2016]494)
文摘Metal complexes with excellent nonlinear optical（NLO） properties have attracted considerable attention. The geometry structure, electronic spectra and NLO properties of 2,2？-bidipyrrins（L） and mono-and bimetal Ir（I）/Rh（I）–L complexes have been investigated by density functional theory method. Our calculations revealed that L with planar configuration shows the largest first hyperpolarizability value, which is 2.2 to 5.5 times larger than that of others. It is attributed to the single direction of intramolecular charge transfer. When metal ions were embedded in ligands, the first hyperpolarizability values of mono-and bimetal Ir/Rh（I）–L complexes were smaller than that of L, and that of bimetal Ir/Rh（I）–L complexes were smaller than the corresponding monometallic Ir/Rh（I）–L. This is caused by the intramolecular charge transfer from multiple directions as well as the amount of charge transfer. On the other hand, on increasing the number of metal ions, the charge transfer in the opposite direction cancels each other more obviously. Our work would provide some theoretical reference for the second-order NLO responses of mono-and bimetal complexes.
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.
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 α-methylstyrene was investigated in the presence of monodentate phosphine ligands L1-L6. We found that the phosphine with good n-acceptability could efficiently improve the activity of the α-methylstyrene hydroformylation. The big steric hindrance ofα-C in α-methylstyrene enhanced the regioselectivity towards the linear aldehyde, which resulted in 3-phenylbutanal as the predominant product （〉99.0%）. When tris（N-pyrrolyl）phosphine （L1） modified Rh（acac）（CO）2 was employed as the catalyst, the TOF could reach up to 5786 h 1 in the α-methylstyrene hvdroformvlation at relatively mild conditions （110 ℃, 6 MPa）.
