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1.
 将合成的三 (3,4-二甲氧基苯基) 膦 (TDMOPP) 用作 Rh 催化剂配体, 并用于 1-十二烯氢甲酰化反应, 考察了膦/铑比和反应温度对 Rh-TDMOPP 催化剂活性和选择性的影响. 结果表明, 在膦/铑比与反应温度较低时, Rh-TDMOPP 活性是 Rh-三苯基膦催化剂的 3 倍.  相似文献   

2.
新型水溶性膦铑络合物催化烯烃的氢甲酰化反应研究   总被引:10,自引:1,他引:10  
燕远勇  左焕培 《分子催化》1994,8(2):147-150
新型水溶性膦铑络合物催化烯烃的氢甲酰化反应研究燕远勇,左焕培,金子林(大连理工大学化工学院,大连116012)关键词烯烃,水溶性膦铑络合催化剂,氢甲酰化,醛.1.前言为克服催化剂的流失和与反应产物的分离困难,近年来均相催化的一个重要进展是开发了以磺化...  相似文献   

3.
The rhodium-catalyzed hydroformylation of 1-dodecene was investigated with a series of sulfonated water-soluble phosphine ligands at a pressure of 60 bar CO/H2 and a temperature of 120 °C. Seven different groups of water-soluble phosphines were used for our investigations. We established an optimized ligand/rhodium ratio of 5 for the phosphines 1a, [Ph2P(CH2)2S(CH2)2SO3Na], and 1b, [Ph2P(CH2)2S(CH2)3SO3Na]. The utilized arylphosphino-thioether-alkylsulfonates formed with Rh(I) compounds highly active catalysts which could be recycled. The addition of detergents speeds up the hydroformylation reaction, but disturbs the phase separation (recycling). The best promotion effect and the smallest negative influence on phase separation gave polyoxyethylene–polyoxypropylene–polyoxyethylene triblock co-polymers. The ratio of 1-dodecene/rhodium could be increased up to 10.000 and we achieved turnover numbers (TONs)>50.000 without any surfactant and TONs of about 65.000 in presence of the co-polymers owing to the recycling on the catalytic system.  相似文献   

4.
合成了几种具有刚性连接基团的双子表面活性剂,研究了它们在Rh-TPPTS体系中催化长链烯烃氢甲酰化反应中的助催化作用.结果表明,在水/有机两相催化体系中,新型双子表面活性剂的助催化作用比单链表面活性剂CTAB更好,在较低的表面活性剂浓度下能得到较高的反应转化率.这归因于此类表面活性剂有较低的cmc,降低界面张力的能力和对1-十二烯的增溶能力比CTAB更强.  相似文献   

5.
TiO2 nanotubes supported amorphous Co-B(Co-B/TNTs) catalyst was prepared via impregnationchemical reduction procedure. The catalyst was characterized with transmission electron microscopy(TEM), ammonia temperature-programmed desorption(NH3-TPD), thermogravimetry-differential thermal analysis(TG-DTA), Fourier transform infrared spectroscopy(FTIR) and Raman spectroscopy. The effects of temperature and ratio of CO to H2 on the hydroformylation of 1-octene were studied. At an optimized reaction temperature(150℃) and volume ratio of CO to H2(2:1), the conversion of 1-octene can reach 97.4% with a selectivity of 23.1% for total aldehydes and n/i-aldehyde molar ratio of 40:60. To obtain higher selectivity for linear aldehydes, Co-B/TNTs modified with triphenylphosphine for the hydroformylation of 1-octene were investigated. When molar ratio of P/Co was 4, the yield of total aldehydes was the highest(31.6%) with a good selectivity for linear product(n/i-aldehyde molar ratio was 70:30). In recycle use, the Co-B/TNTs catalyst modified with triphenylphosphine could be reused five times without reducing the activity and selectivity obviously. For a comparative study, all the Co-B/TNTs to catalyze the hydroformylation of other olefins exhibited high conversion under the optimized conditions.  相似文献   

6.
铑-膦配位催化烯烃氢甲酰化反应研究   总被引:7,自引:1,他引:6  
本文研究了由Rh2(CO)4CI2分别与两种膦配体4-下丁苯基二苯基膦(1)和4-正辛苯基二苯基磷(2)形成的原位催化剂体系对烯烃氢甲酰化反应的催化性能。对影响反应的各种因素,如P/Rh物质的量比、反应温度、反应压力,不同烯烃等的影响作了探讨。结果表明,配体1、2与Rh2(CO4)CI2形成的原位催化剂体系的催化活性与选择性均高于结构相似的PPh3,在相同的条件下,不同烯烃的氢甲酰化反应活性依直链烯烃>苯乙烯>直链内烯>环己烯的顺序递增。  相似文献   

7.
报道了水溶性铑膦配合物组成的复合催化体系催化1-十二烯氢甲酰化反应中,双子表面活性剂[二溴化-(N,N,N′,N′-四甲基)-N,N′-二(十六烷基)-乙二铵]形成胶束的助催化作用.结果表明,在水/有机两相中,双子表面活性剂比单链表面活性剂CTAB具有更好加速催化反应的作用,并使烯烃氢甲酰化的区域选择性显著提高.这归因于双子表面活性剂有较低的cmc,可形成更加紧密规整的胶束结构,有利于增溶在胶束中的烯烃与铑催化剂配位和生成正构醛.  相似文献   

8.
Trivalent phosphorus compounds are promoters for methyl formate homologation to ethanol and ethyl formate catalyzed by ruthenium compounds in the presence of iodide at 220°C and 27 MPa of synthesis gas. Under these conditions the phosphines are quaternized, but decomposition of phosphonium salts occurs during the reaction. Promotion is also observed for methyltriphenyl-phosphonium bromide and triphenylphosphine sulfide, but benzyltrimethyl-ammonium bromide, triphenylarsine, and triphenylantimony are not effective. The major ruthenium species present is Ru(CO)3I3- but with triphenylantimony a trimethylantimony complex, Ru(CO)2(Sb(CH3)3)2I2, can be isolated in high yield.  相似文献   

9.
The full details of the asymmetric epoxidation of α,β‐unsaturated esters catalyzed by yttrium complexes with biaryldiol ligands are described. An yttrium–biphenyldiol catalyst, generated from Y(OiPr)3–biphenyldiol ligand–triphenylarsine oxide (1:1:1), is suitable for the epoxidation of various α,β‐unsaturated esters. With this catalyst, β‐aryl α,β‐unsaturated esters gave high enantioselectivities and good yields (≤99 % ee). The reactivity of this catalyst is good, and the catalyst loading could be decreased to as little as 0.5–2 mol % (the turnover number was up to 116), while high enantiomeric excesses were maintained. For β‐alkyl α,β‐unsaturated esters, an yttrium–binol catalyst, generated from Y(OiPr)3–binol ligand–triphenylphosphine oxide (1:1:2), gave the best enantioselectivities (≤97 % ee). The utility of the epoxidation reaction was demonstrated in an efficient synthesis of (?)‐ragaglitazar, a potential antidiabetes agent.  相似文献   

10.
《Tetrahedron: Asymmetry》2005,16(19):3198-3204
Several new chiral P,N-ligands were prepared from 1,2:5,6-di-O-cyclohexylidene-d-mannitol, 1,1′-binaphthol, and phenyl isocyanate derivatives. Their Rh(I) complexes were applied as catalyst precursors in the asymmetric hydroformylation of vinylarenes. The steric and electronic properties of the phenylcarbamate substituents and the chiral binaphthyl moiety showed remarkable effects on the enantioselectivity and regioselectivity of the reaction. The matching combination of phenylcarbamate and the binaphthyl moiety of the ligand 1,2:5,6-di-O-cyclohexylidene-3-phenylcarbamate-4-[(S)-1,1′-binaphthyl-2,2′-diyl]phosphite-d-mannitol gave 50% ee and an 89/11 b/n ratio (branch-to-normal ratio). A synergic effect between the chiralities of mannitol and the binaphthol moieties was observed. Hydroformylation of the styrene gave the product in 75% ee when 1,2:5,6-di-O-cyclohexylidene-3,4-bis[(R)-1,1′-binaphthyl-2,2′-diyl]phosphite-d-mannitol was used as the chiral ligand.  相似文献   

11.
Rhodium nanoparticles of about 3 nm in size were provided in stabilizing polar solvents. These nanoparticles were used in hydroformylation reactions of higher alkenes; 1-dodecene was used as a model substance. With a metal/substrate ratio of 1:1000, a 97% yield of aldehydes was achieved and an n/iso ratio of 72:28 was obtained. The addition of the ligand biphephos decelerated the reaction, but high n/iso ratios of up to 96:4 were achieved.For the first time, an effective catalyst recycling of these long-term stable nanoparticles in a thermomorphic multicomponent solvent (TMS) system was performed. The catalyst phase was recycled for three runs without any evident loss in activity. TEM images proved that after the recycling runs rhodium nanoparticles were still the active catalyst.  相似文献   

12.
A palladium(0) complex catalyzes the addition reaction of a triarylphosphine and a protic acid to a 1-alkene, giving a 1-alkylphosphonium salt. The treatment of atmospheric ethylene, triphenylphosphine, and (CF3SO2)2NH in the presence of Pd2(dba)3.CHCl3 (dba = dibenzylideneacetone) (0.1 mol %) in chlorobenzene at 65 degrees C for 5 h gave ethylphosphonium salt in 98% isolated yield. The anti-Markovnikov adduct 1-propylphosphonium salt was obtained by the reaction of atmospheric propene in 95% yield. 1-Butene was converted to 1-butylphosphonium salt in 92% yield in the presence of 1 mol % catalyst. This reaction competed with olefin isomerization, and a mixture of 2-butene and 1-butene (>20:1) was recovered. The reactions of 1-pentene and 1-hexene with triphenylphosphine gave modest yields of the products. The less reactive 1-alkenes, however, reacted effectively with tris(p-chlorophenyl)phosphine. The inner olefins, 2- and 3-pentene also gave a 1-pentylphosphonium salt in high yields via rapid olefin migration.  相似文献   

13.
Photolytic substitutions of iron selenocarboxylate complexes CpFe(CO)2SeCOR with triphenylphosphine, triphenylarsine or triphenylantimony (EPh3) gave exclusively the monosubstituted complexes CpFe(CO)(EPh3)SeCOR [R = 3,5-C6H3(NO2)2 (1), 4-C6H4NO2 (2), Ph (3), 2-C6H4Me (4), and E = P (a), As (b), Sb (c)] in high yields.  相似文献   

14.
《Tetrahedron letters》1997,38(24):4315-4318
The rhodium catalysed reactions of N-allyl- and N-butenyl-1,3-diaminopropanes give single products arising from exclusive hydroformylation at the terminal carbon when the hindered bisphosphite ligand, BIPHEPHOS is used. Reactions using a high carbon monoxide: hydrogen ratio (9:1) and triphenylphosphine as ligand give predominantly lactams arising from carbonylation but with poor control of regioselectivity.  相似文献   

15.
有机化合物PDBP的合成及其在催人反应中的应用   总被引:3,自引:2,他引:1  
用量子化学AM1方法优化了1-苯基二苯并膦(PDBP)和三苯基膦(TPP)的几何构型,比较了两种化合物的电子结构和空间结构,发现PDBP作为羧基合成铑膦催化剂的配体要优于三苯基膦(TPP);系统研究了PDBP的合成方法,其最佳合成条件为:在无水无氧的条件下,采用二乙胺锂与溴化四苯基膦摩尔比为3,反应温度为22℃,反应5h,反应后酸化,pH值为1-2,产物收率可达到85%-88%,采用元素分析、红外、核磁等方法,对其结果进行了表征,并将PDBP用于丙烯氢甲酰化反应的催化剂配体。实验证明,在相同的反应条件下,以其为配体的催化剂活性约是目前工业上使用的以三苯基膦为配体的催化剂的1.2倍,选择性约为其1.7倍。  相似文献   

16.
Rhodium-catalyzed hydroformylation of 1-octene in the presence of different phosphine and phosphine oxide ligands has been investigated. The molecular structure of new phosphine ligand, fluorenylidine methyl phenyl diphenylphosphine, was determined by single-crystal X-ray crystallography. Parameters such as different ligands, molar ratio of ligand to rhodium complex, ratio of olefin to rhodium complex, pressure of CO : H2 mixture, and time of the reaction were studied. The linear aldehyde was the main product when the phosphine ligands were used as auxiliary ligands while the selectivity was changed to the branched products when the related phosphine oxide ligands were used. Under optimized reaction conditions, in the presence of [Rh(acac)(CO)(Ph3P)]-di(1-naphthyl)phenyl phosphine oxide, conversion of 1-octene reached 97% with 87% selectivity of branched aldehyde.  相似文献   

17.
新型双膦配体的合成及其在2-丁烯氢甲酰化反应中的应用   总被引:1,自引:0,他引:1  
合成了以联苯为骨架,以吲哚为取代基的双膦配体,并研究了该配体与Rh(acac)(CO)2原位生成的催化剂在2-丁烯氧甲酰化反应中的催化性能.考察了膦/铑比、反应温度、反应压力以及2-丁烯与Rh(acae)(CO)2摩尔比等因素对反应活性及区域选择性的影响.结果表明,在60℃反应时,醛的正异比高达28.5;当压力为2.0...  相似文献   

18.
The promotion effect of cationic gemini surfactants for the hydroformylation of 1-dodecene in the organic/aqueous biphasic catalytic system is reported. The hydroformylation reaction in the presence of gemini surfactant occurred with higher turnover frequency and higher selectivity for linear aldehyde than using conventional monomeric surfactant CTAB.  相似文献   

19.
A series of mono- and bidentate phosphites was prepared with (S)-5,5',6,6'-tetramethyl-3,3'-di-tert-butyl-1,1'-biphenyl-2,2'-dioxy [(S)-BIPHEN] as a chiral auxiliary and screened in the asymmetric hydroformylation of allyl cyanide. These hydroformylation results were compared with those of two existing chiral ligands, Chiraphite and BINAPHOS, whose utility in asymmetric hydroformylation has been previously demonstrated. Bisphosphite 11 with a 2,2'-biphenol bridge was found to be the best overall ligand for asymmetric hydroformylation of allyl cyanide with up to 80% ee and regioselectivities (branch-to-linear ratio, b/l) of 20 with turnover frequency of 625 [h(-)(1)] at 35 degrees C. BINAPHOS gave enantioselectivities up to 77% ee when the reaction was conducted in either acetone or neat but with poor regioselectivity (b/l 2.8) and activities 7 times lower than that of 11. The product of allyl cyanide hydroformylation using (R,R)-11 was subsequently transformed into (R)-2-methyl-4-aminobutanol, a useful chiral building block. Single-crystal X-ray structures of (S,S)-11 and its rhodium complex 19 were determined.  相似文献   

20.
以硅胶为载体, 采用键合接枝法将2-(二苯膦基)乙基三乙氧基硅烷(DPPES)共价键合于硅胶表面, 制备了性能优良的硅胶键合型膦配体(以SiO2(PPh2)表示). 以SiO2(PPh2)为配体, Rh(acac)(CO)2 (acac:乙酰丙酮)为催化前体, 负载铑膦络合物催化剂(SiO2(PPh2)/Rh)在1-辛烯氢甲酰化反应中原位生成. 对生成的负载型催化剂和硅胶键合型膦配体进行了傅里叶变换红外(FTIR)光谱表征, 考察了膦/铑摩尔浓度比([P]/[Rh])、温度等因素对铑催化的长链1-辛烯氢甲酰化反应的影响. 结果表明, 膦/铑摩尔浓度比的增加能显著提高反应的成醛选择性, 降低铑的流失. 在[P]/[Rh]=12、363 K、2.0 MPa、1.5 h 的温和反应条件下, 1-辛烯转化率和成醛选择性分别可达98.4%和95.3%, 其催化活性与DPPES或三苯基膦(TPP)作配体时的均相铑催化相近. 催化剂循环4 次后, 反应活性无明显下降, 1-辛烯转化率均在97.0%左右, 经电感耦合等离子体原子发射光谱(ICP-AES)检测,有机相中铑流失低于0.1%.  相似文献   

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