Recycle and recovery of rhodium complexes with water-soluble and amphiphilic phosphines in ionic liquids for hydroformylation of 1-hexene

A biphasic catalysis system composed of ionic liquid and rhodium complexes with water-soluble or amphiphilic phosphine ligands bearing water-soluble groups of sodium sulfonate have been employed for hydroformylation of 1-hexene. The experimental results show that the activity is almost independent of the hydrotropicity of the phosphine ligands in BMI·BF₄. In this system, the extraction of phosphine species by the organics from the IL phase was quite low but larger than that of rhodium species and showed rather good stability of catalytic activity. A slight decrease in the aldehyde n/i ratio during the catalyst reuse could be recovered, in part, by replenishing certain amount of ligand into the used catalyst system.     

2,2′-Bis((di-tert-butylphosphino)methyl)-1,1′-biphenyl (ditbi): a bulky analogue of bisbi. The crystal structure of [Rh2Cl2(1,5-cod)2(μ-ditbi)]

Diphosphine 2,2′-bis(di-tert-butylphosphino)methyl)-1,1′-biphenyl (ditbi) is synthesised by the addition of to 2,2′-bis(bromomethyl)-1,1′-biphenyl, followed by deprotection with diethylamine. Treatment of [Rh₂Cl₂(1,5-cod)₂], with ditbi gives [Rh₂Cl₂(1,5-cod)₂(μ-ditbi)] (2) as confirmed by its X-ray crystal structure determination. Hydroformylation of 1-hexene using [Rh(acac)(CO)₂]/ditbi as catalyst gave n- and iso-heptanal in a ratio of 1:1.     

水溶性铑－膦配合物催化1－十二碳烯常压氢甲酰化反应研究

本文研究了水溶性铑配合物ＲｈＣｌ（ＣＯ）（ＴＰＰＴＳ）２在常压（ＣＯ：Ｈ２＝１：１）条件下对１－十二碳烯氢甲酰化反应的催化性能，并对催化剂浓度、表面活性剂浓度、溶液ｐＨ值、膦铑比、溶剂等因素的变化对催化活性的影响作了考察．结果表明，表面活性剂（ＣＴＡＢ）的加入，可以在反应体系中形成胶束．加速有机相和水相间的传质速度，从而提高催化转化速度．在反应温度（８０℃）下，ＣＴＡＢ的临界胶束浓度（ＣＭＣ）较室温下高．达到最佳催化活性的ｐＨ范围为７～９，［Ｐ］／［Ｒｈ］比为１６，而有机溶剂的加入则使转化数降低．     

Novel functionalised P-ligands: advances and application

Novel endo- and exocyclic phosphine ligands possessing different functionalities obtained by reduction of the PO precursors with desired stereochemistry are discussed. The diastereoselective deoxygenation including the catalytic reduction processes, the factors defining the reactivity and the role of the substituents on the stability of phosphorus atom configuration in a series of 3-aryl-3-phosphabicyclo[3.1.0]hexanes are reported. The complexation features of the ligands with Rh(III) and Pd(II) were examined and Rh(III) complexes were tested in styrene hydroformylation showing the structure-activity dependence.     

水溶性铑－膦配合物催化长链烯烃氢甲酰化反应研究──反应条件的影响

本文研究了两相催化体系中，在ＣＴＡＢ（Ｃ＿（１６）Ｈ＿（３３）ＮＭｅ＿３Ｂｒ）存在下，水溶性铑－膦配合物ＲｈＣｌ（ＣＯ）（ＴＰＰＴＳ）＿２对１－己烯氢甲酰化反应的催化性能，详细考察了反应温度、压力、膦／铑比等对催化活性的影响。结果表明，在１．０ＭＰａ恒压下，反应温度１００℃，膦／铑摩尔比为１６，Ｈ＿２：ＣＯ＝１：１的条件下，１－己烯氢甲酰化的转化频率（ＴＯＦ）可达到３９．８ｍｉｎ￣（－１）。在此反应条件下，有机相和水相容易分离，铑－膦配合物流失到有机相中的量极小。     

两相催化体系中双子表面活性剂对1-十二烯氢甲酰化反应的助催化作用

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.     

[Rh(μ-Cl)(COD)]2 supported on activated carbons for the hydroformylation of 1-octene: effects of support surface chemistry and solvent

The [Rh(μ-Cl)(COD)]₂ complex has been heterogeneised on activated carbon and used as catalysts for the hydroformylation of 1-octene. The objective is to achieve the effective anchorage of the complex on the carbon surface, keeping or improving the catalytic properties of the complex in the homogeneous process. The effects of surface chemistry of the activated carbon and the solvent used as reaction media (hexane, acetone or methanol) on the activity and selectivity to linear products (alcohols and aldehydes) and on the lixiviation of the complex from support, using different methods of catalyst recovering, are investigated. Gas adsorption, temperature-programmed desorption (TPD), immersion calorimetry and XPS techniques were used for characterisation. Catalytic activity at 353 K and a total pressure of 5 MPa (H₂:CO ratio 1:1) was carried out in a stainless steel stirred tank reactor. Obtained results show that the heterogeneised complex shows a conversion level higher or similar to that of the homogeneous complex and with a higher selectivity to the linear products. Complex lixiviation depends on the support, the solvent and the method used to recover the catalyst from the reactor. The catalyst prepared with the functionalised activated carbon, where the anchorage takes place by ion-exchange, is more stable and active in further catalytic runs using the proper recovering method.     

Synthesis,characterization and evaluation of heterobimetallic Fe(II)/Rh(I) and Fe(II)/Ru(II) complexes as catalyst precursors for hydroformylation of 1-octene

Abstract

Two new ferrocenyl iminopyridyl ligands, L1 and L2, have been synthesized and characterized using spectroscopic and analytical techniques. Both ligands were used to prepare new Rh(I) and Ru(II) ferrocenyl complexes 1–4. The structures of the complexes were confirmed using ¹H and ¹³C nuclear magnetic resonance spectroscopy, high resolution electrospray ionization mass spectrometry, and infrared spectroscopy. The complexes were tested as catalysts in the hydroformylation of 1-octene. Rh ferrocenyl complexes 1 and 4 produced aldehydes under mild conditions while the Ru-ferrocenyl complexes 2 and 3 required higher temperature and pressure for effective hydroformylation to occur. The catalysts display excellent aldehyde chemoselectivity with varying regeoselectivity depending on temperature and pressure conditions employed. At high temperatures, the Rh ferrocenyl precatalysts favor formation of branched aldehydes due to increased isomerization at high temperatures. The Ru ferrocenyl precatalysts displayed less hydroformylation activity; however, the complexes show good chemoselectivity for aldehydes with no hydrogenation products formed.     

Phosphite Ligand Modified Supported Rhodium Catalyst for Hydroformylation of Internal Olefins to Linear Aldehydes

A phosphite ligand modified heterogeneous catalyst was developed for the hydroformylation of internal olefins to linear aldehydes, which showed a high activity and high regioselectivity and could be separated easily by filtration after reaction in an autoclave. Three nanoporous silica sieves were used to investigate the influence of pore structure and shape selective performance of support on the regioselectivity to the linear products.     

Platinum complexes of 2-diphenylphosphinobenzaldehyde-derived P-alkene ligands and their application in the hydroformylation of styrene

Neutral complexes of the formula PtCl₂L₂ (where L = diethyl 2-diphenylphosphino-benzylidene-malonate (1), diisopropyl 2-diphenylphosphino-benzylidene-malonate (2), di-tert-butyl 2-diphenylphosphino-benzylidene-malonate (3), methyl E-2-(2′-diphenylphosphinophenyl)-acrylate (4), tert-butyl E-2-(2′-diphenylphosphinophenyl)acrylate (5)) were prepared. These complexes proved to be excellent precursors to active catalysts for the hydroformylation of styrene. The platinum-containing catalytic systems prepared from malonate-based ligands 1 and 2 provided the highest activity. Chemoselectivities of up to 87% were obtained, while the two aldehyde regioisomers were formed in almost equimolar ratio. The in situ studies by using lower ligand to Pt ratios resulted in slight decrease in both regio- and chemoselectivities.³¹P NMR studies on the PtCl₂L₂ complexes revealed that the formation of trans isomers is highly preferred in the case of benzylidene malonate-type ligands with two ester functionalities (1-3) probably due to steric hindrance. A mixture of cis/trans geometrical isomers (on the Pt) with a predominance of the trans isomer was formed when acrylate-type ligands with one ester functionality (4 and 5) were used.