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1.
考察了水溶性铑膦络合物RhCl(CO)(TPPTS)2(TPPTS为间-三苯基膦三磺酸钠)在水/有机两相体系中对不同单萜烯的氢甲酰化反应的催化性能.结果表明,添加表面活性剂对催化活性影响很大.在8.0 MPa,100℃的条件下,该催化体系对萜烯氢甲酰化反应具有较好的催化活性,月桂烯、莰烯和艹宁烯的转化率可分别达到92%,72%和86%.反应完成后,含水溶性铑膦络合物的水溶液与含产物的有机相分离方便,催化剂重复使用8次,其活性和选择性均未明显下降,易于实现催化剂的循环使用.  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.
An organo-nanoclay is used as a new, easily accessible, and stable solid sorbent for the preconcentration of trace amounts of rhodium ions from aqueous solution, this followed by its determination by flame atomic absorption spectrometry (FAAS). Rh(III) ion was first complexed with 2,3,5,6-tetra(2-pyridyl) pyrazine (TPPZ) at pH values between 3.0 and 4.7, and then the complex was then adsorbed onto the nanoclay. The rhodium ions were eluted from the sorbent with HCl. The rhodium in the effluent was determined by FAAS. The linear analytical range is between 0.14 ng mL?1 and 20.0 μg mL?1 in the initial solution, the relative standard deviation at 2.0 μg mL?1 of rhodium is 2.6% (n?=?8), the detection limit is 0.03 ng mL?1, and the preconcentration factor is 140. Experimental parameters including the pH, eluent type, interference by other ions and breakthrough volume were optimized. The method was applied to the determination of rhodium in water, road dust and synthetic samples.  相似文献   

4.
烯烃氢甲酰化反应研究进展   总被引:4,自引:1,他引:4  
本文综述了烯烃氢甲酰化反应的催化剂从钴配合物到铑配合物和从均相催化体系到两相催化体系的发展过程。比较了三种催化剂和两个催化体系的特点、应用情况及研究工作进展.  相似文献   

5.
从(R)-BINAP出发制备水溶性磺酸钠盐配体(R)-BINAPS,采用离子液体BF4和PF6为介质,实现其Rh配合物对乙酸乙烯酯的两相不对称氢甲酰化反应.实验结果表明,在以BF4为介质的乙酸乙烯酯不对称氢甲酰化反应中,该催化剂在温和条件下显示出高于相应均相体系的产物ee值和异构醛选择性,并在6次循环使用中,反应产物的ee值、选择性和转化率均无明显改变;在离子液体体系中添加适当的甲苯时,油溶性配体(R)-BINAP与Rh组成的配合物催化剂亦可形成类似的两相反应体系,但其活性和选择性在重复使用中呈明显下降趋势.本文还考察了溶剂体系、膦铑比、温度、压力、时间等的影响,并尝试苯乙烯的两相不对称氢甲酰化反应.  相似文献   

6.
The organic/aqueous biphasic hydroformylation of 2,5‐norbornadiene (NBD) was investigated for the first time using HRh(CO)(TPPTS)3 (TPPTS: trisodium salt of tri(m‐sulphonylphenyl)phosphine) as the catalyst precursor. A comparison was made of homogeneous and biphasic systems. The optimum reaction parameters are discussed and the reaction mechanism is presented. In order to ensure the process attained high activity under moderate conditions, the effect of various cationic surfactants was tested in the biphasic hydroformylation of NBD. The results indicated that the hydroformylation of NBD in the biphasic system exhibited high activity and high selectivity to dialdehyde products under mild conditions. The addition of cationic surfactants markedly accelerated the reaction. A single long‐chain surfactant seemed to exert a greater impact on the hydroformylation of NBD than a double long‐chain surfactant. Moreover, the recycling of aqueous solution containing catalyst with or without surfactant was investigated. In the absence of the surfactant, the aqueous catalyst could be recycled six times without a significant decrease in activity and selectivity. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

7.
Attachment of phosphites to styrene copolymers is described which are used as rhodium hydroformylation catalysts. The influence of the chain loading on the activity and complex formation of three types of copolymer-bound rhodium hydroformylation catalysts in comparison with their low molecular weight analogues has been studied. The catalytic activity of the polystyrene-bound system with the most bulky phosphite, the first system studied, is identical to that of the low molecular weight analogue. The catalysts show a high activity towards the hydroformylation of the otherwise unreactive cyclooctene. It was found that only one phosphite is coordinated to the rhodium complex in its active form. An equilibrium between this complex and an inactive complex without phosphite ligands prohibits its use in continuous flow reactors. Secondly, as polymer support a perfectly random copolymer of styrene and less bulky 3,3′,5,5′-tetra-tert-butylbiphenyl-2,2′-diyl p-vinylphenylphosphite was used. The chain loading α of this copolymer with phosphite ligands has a large influence on the complex formation of the catalyst. With high chain loadings moderately active bis-phosphite catalysts are formed. Low chain loadings give active, easily accessible, monophosphite complexes. The active species in the hydroformylation of sterically hindered alkenes is a mono-phosphite rhodium complex. The activity of the copolymer-bound catalyst towards the hydroformylation of cyclooctene is found to be as high as the activity of its low molecular weight analogue. For styrene, this polymer catalyst yields a slower catalyst than the low-molecular weight analogue. The third part demonstrates that silica-grafted polymer-bound phosphite modified rhodium complexes can be used in continuous flow reactors. The hydroformylation of styrene was carried out at moderate pressure (pCO/H2 = 3 MPa) and temperature (T = 100°C), yielding constant conversions over a period of at least ten days. These positive results were obtained in benzene as a solvent and for a ligand to rhodium ratio of only four.  相似文献   

8.
付海燕  郭妤  林棋  陈华  李贤均 《催化学报》2006,27(12):1053-1058
 考察了新型表面活性膦配体DPPTS(对-十二烷基苯基二苯基膦的磺酸钠盐)和OPPTS(对-辛基苯基二苯基膦的磺酸钠盐)在铑络合物催化的水/有机两相长链烯烃氢甲酰化反应中的助催化作用. 在催化烯烃氢甲酰化反应时,观察到烯烃与膦配体之间有一定的链长匹配效应; 含DPPTS的催化剂体系在低膦/铑比条件下表现出比含表面活性剂十六烷基三甲基溴化铵和水溶性配体三苯基膦三磺酸钠的催化剂体系高得多的催化活性,而且铑流失到有机相极少,仅为加入总铑量的0.8%. 这种亲水基团和磷原子处于碳链同一端的表面活性膦配体比文献报道的亲水基团和磷原子分别处于碳链两端的表面活性膦配体具有更好的助催化活性.  相似文献   

9.
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   

10.
李考学  王艳华  蒋景阳  金子林 《催化学报》2010,31(10):1191-1194
 基于温控配体 Ph2P(CH2CH2O)16CH3 稳定的 Rh 纳米催化剂在水/1-丁醇两相体系中具有温控相转移功能, 将其用于高碳烯烃氢甲酰化反应中. 在优化的反应条件下, 1-辛烯转化率和醛收率分别达 98% 和 96%, 对其它高碳烯烃氢甲酰化反应也具有较高的催化性能. 催化剂和产物通过简单的相分离即可分开, 连续使用 3 次后, 催化剂性能未见明显降低.  相似文献   

11.
The chlorocarbonyl bis-[butylphenyl (meta-sulfonate-phenyl)phosphine] rhodium (I) complex shows catalytic hydroformylation activity in toluene/water biphasic medium for 1-hexene, cyclohexene, 2,3-dimethyl-2-butene and 2-methyl-2-pentene, their binary mixtures and a real Venezuelan naphtha, under standardized reaction conditions (1000 psi of syngas (1:1 H2/CO), 100°C, substrate/catalyst molar ratio (600:1) and 4 h reaction time), obtaining high percent conversion to oxygenated products.  相似文献   

12.
A biphasic catalytic system with water-soluble rhodium complexes of sulfonated (R)-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (labeled as (R)-BINAPS) in ionic liquid BMI·BF4 has been developed for the asymmetric hydroformylation of vinyl acetate under mild conditions. The corresponding ruthenium complexes have been investigated for the biphasic asymmetric hydrogenation of dimethyl itaconate. The biphasic asymmetric hydroformylation of vinyl acetate provided 28.2% conversion and 55.2% enantiomeric excess when BMI·BF4–toluene was used as the reaction medium at 333 K and 1.0 MPa for 24 h. The biphasic asymmetric hydrogenation of dimethyl itaconate in BMI·BF4iPrOH at 333 K and 2.0 MPa afforded 65% enantiomeric excess with an activity similar to the homogenous analogs. Both biphasic catalytic systems with (R)-BINAPS ligand could be reused several times without significantly decrease in the activity, enantio- and regio-selectivities. The effects of properties of ionic liquid, molar ratio of ligand to rhodium, temperature, pressure and reaction time have been discussed.  相似文献   

13.
New dinuclear Rh(I)–Phosphines of the types [Rh(µ‐azi)(CO)(L)]2 ( 1,3 – 7 ) and [Rh(µ‐azi)(L)]2 ( 8 ) with pendant polar groups, and a chealated mononuclear compound [Rh(azi‐H)(CO)(L)] ( 2 ) (where azi = 7‐azaindolate, L = polar phosphine) were isolated from the reaction of [Rh(µ‐Cl)(CO)2]2 with 7‐azaindolate followed by some polar mono‐ and bis‐phosphines ( L 1 – L 8 ). A relationship between Δδ31P‐NMR and ν(CO) values was considered to define the impact of polar‐groups on σ‐donor properties of the phosphines. These compounds were evaluated as catalyst precursors in the hydroformylation of 1‐hexene and 1‐dodecene both in mono‐ and biphasic aqueous organic systems. While the biphasic hydroformylations (water + toluene) gave exclusively the aldehydes, the monophasic one (aqueous ethanol) showed propensity to form both aldehydes and alcohols. The influence of bimetallic cooperative effects, and σ‐donor and hydrophilic properties of the phosphines with pendant polar‐groups in enhancing the yields and selectivity of hydroformylation products was emphasized. In addition, when strong σ‐donor phosphine was used, the π‐acceptor nature of pyridine ring of 7‐azaindolate spacer was found to be a considerable factor in facilitating the facile cleavage of CO group during hydroformylation and in supplementing the cooperative effects. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

14.
A family of threefold symmetry phosphite ligands, P(O–BIN–OR)3 (BIN = 2,2′-binaphthyl; R = Me, Bn, CHPh2, 1-adamantyl), derived from enantiomerically pure (R)-BINOL, was developed. Cone angles within the range 240–270° were calculated for the phosphite ligands, using the computational PM6 Hamiltonian. Their rhodium complexes formed in situ showed remarkable catalytic activity in the hydroformylation of hindered phenylpropenes, under relatively mild reaction conditions, with full chemoselectivity for aldehydes, high regioselectivity, however with low enantioselectivity. The ether substituents at the ligand affected considerably the catalytic activity on the hydroformylation of 1,1- and 1,2-disubstituted aryl olefins. The kinetics of the hydroformylation of trans-1-phenyl-1-propene, using tris[(R)-2′-benzyloxy-1,1′-binaphthyl-2-yl]phosphite as model ligand, was investigated. A first order dependence in the hydroformylation initial rate with respect to substrate and catalyst concentrations was found, as well as a positive order with respect to the partial pressure of H2, and a slightly negative order with respect to phosphite concentration and CO partial pressure.  相似文献   

15.
黄裕林  黎耀忠 《分子催化》1999,13(3):215-218
在烯烃氢甲酰化反应两相催化体系中,为提高催化剂活性及选择性,有采用外加无机盐的报道[1~3].从这些文献可以看出,某些无机盐在反应中起到催化助剂的作用.我们曾经研究了硫酸钠及其它金属硫酸盐中的阳离子对反应的影响[4,5].在引入这些阳离子的同时,还有...  相似文献   

16.
A kind of nonphosphine polymer catalyst has been synthesized by partial substitution of the chlorine atoms of poly(vinyl chloride) with -SR groups (n-propyl, n-hexyl, benzyl, and p-tolyl). Rhodium complexes of these sulfur-containing polymer ligands are highly active catalysts for the hydroformylation of α-olefins. At 60°C and 60 kg/cm2, conversion of 1-hexene was nearly complete within 4–6 h. The rhodium to 1-hexene mole ratio was 1/800 to 1/1 000, and the catalyst could be reused once again without losing activity. The effects of reaction temperature, pressure, H2/CO ratio, S/Rh ratio, concentration of catalyst, and reaction time on the catalyst's activity were examined. The possible mechanism of hydroformylation is discussed. A copolymer of butyl vinyl sulfide and acrylonitrile was synthesized and its rhodium complex was prepared. The catalytic acitvities of this complex for the hydroformylation of 1-hexene was also investigated.  相似文献   

17.
A chelating phosphine monomer, 4-triethoxysilyl-1,2-bis(diphenylphosphino)benzene ( 9 ), was prepared in three steps from 2,4-dibromoiodobenzene. Attachment of 9 to the surface of commercial silica gel, followed by chelation of rhodium, gave a catalyst which showed both undiminished activity (turnover rates of 90 atom?1 h?1) and no loss of rhodium over five recycles in the hydroformylation of styrene. Complexation of cobalt afforded a catalyst for the homologation of methanol. Monomer 9 could be incorporated into a solgel polymer produced from silicic acid in tetrahydrofuran, but low rhodium uptake and low catalytic activity suggested that few phosphine sites were available to the rhodium. The catalytically-active species were modeled by the synthesis of cobalt and rhodium complexes containing 1,2-bis(diphenylphosphino)benzene.  相似文献   

18.
Polymer-supported η5-cyclopentadienylrhoduim dicarbonyl and η5-cyclopentadienylcobalt dicarbonyl have been prepared with 20% divinylbenzene-polystyrene copolymer, macroporous beads. The beads have been tested for a variety of types of catalytic activity. The cobalt-containing beads have not proven to be catalysts. The rhodium beads were effective in hydrogenation of olefins, aldehydes and ketones, isomerization of olefins, disproportion of 1,4,-cyclohexadiene and cyclohexene, cyclotrimerization of ethyl propiolate, and hydroformylation of 1-pentene and 1-hexene. Decomposition of the rhodium catalysts occurs except in hydroformylation, although only slight loss of the carbonyl groups and catalytic activity was observed in cyclotrimerization.  相似文献   

19.
A cobalt(II) complex [L′CoPy] 1 was prepared by the reaction of dimethylaminoethylamino-N,N-bis(2,4-dibromo)phenol (H2L′) with CoCl2. Electrochemical studies indicate that this complex is among the most efficient homogeneous catalysts for water reduction, with a turnover frequency of 917.7 mol of hydrogen per mole of catalyst per hour at an overpotential of 636.7 mV (pH 7.0). Additionally, under photoirradiation with blue light (λ max = 469 nm), complex 1 in combination with [Ru(bpy)3]Cl2 and ascorbic acid (pH 4.0 in aqueous solution) also produces hydrogen with a turnover number of 4.9 × 105 mol of H2 per mol of catalyst.  相似文献   

20.
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   

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