Hua Chen

Name: 陈华; Chen, Hua

Organization: Sichuan University , China

Department: College of Chemistry

Title: Professor(PhD)

Chemicals
References

Selective hydroformylation of alkyl acrylates using [2,2′-bis(dipyrrolylphosphinooxy)-1,1′-(±)-binaphthyl]/Rh catalyst: reversal of regioselectivity

Co-reporter:Xiao Shu;Haoran Liang;Qianhui Wu;Fanding Zhou;Xueli Zheng;Haiyan Fu;Bin Xu;Ruixiang Li;Chunchun Zhang

RSC Advances (2011-Present) 2017 vol. 7(Issue 24) pp:14816-14823

Publication Date(Web):2017/03/03

DOI:10.1039/C7RA01649B

The rhodium-catalyzed hydroformylation of alkyl acrylates with different P–N diphosphine ligands is investigated here. Under mild conditions (syngas pressure: 2 MPa, 20 °C), 2,2′-bis(dipyrrolylphosphinooxy)-1,1′-(±)-binaphthyl (L1) rhodium catalyst could give good conversion of ethyl acrylate (82.9%) in 12 h and exclusive branched aldehyde selectivity of >99.0%. More importantly, on elevating the temperature to 90 °C, this Rh system could preferentially afford the linear aldehyde with 96.1% regioselectivity, and the TOF could reach up to 9000 h−1. Deuterioformylation was conducted to explore the mechanism of regioselectivity reversal, and the results established that the reversible rhodium hydride addition to form the Rh-alkyl species might play a vital role in this reversal. The β-hydride elimination of branched Rh-alkyl species was comparatively stronger than that of linear ones under increased temperature, probably because L1 could cause comparatively larger steric repulsion in branched Rh-alkyl species under high temperature, due to its bulky and rigid binaphthyl backbone characteristics. In turn, the linear Rh-alkyl species progress to linear aldehyde was facilitated.

Synthesis of phosphorus amidite ligand and investigation of its flexibility impact on rhodium-catalyzed hydroformylation of 1-octene

Co-reporter:Weibiao Han, Song Qin, Xiao Shu, Qianhui Wu, Bin Xu, Ruixiang Li, Xueli Zheng and Hua Chen

RSC Advances 2016 vol. 6(Issue 58) pp:53012-53016

Publication Date(Web):25 May 2016

DOI:10.1039/C6RA09890H

A new flexible 2,2′-bis((dipyrrolylphosphinooxy)methyl)-1,1′-(±)-biphenyl ligand (L1) was synthesized, characterized and employed in the hydroformylation of 1-octene. In order to investigate the influence of ligand flexibility on the catalytic performance, its analogue 2,2′-bis (dipyrrolylphosphinooxy)-1,1′-(±)-biphenyl (L3) was also applied in the hydroformylation of 1-octene. With the presence of L1, the aldehyde selectivity was approximately 10% higher than that with the relevant less flexible ligand L3. Theoretical calculation indicated that the olefin-insertion into the Rh–H bond of intermediate III and the CO-insertion into Rh–alkyl bond of intermediate V were favorable in terms of thermodynamics, which were vital to the generation of aldehyde. Meanwhile, the ligand flexibility was indeed improved by adding a methylene between benzene and oxygen atom that connected with P, as the calculation showed the variation of the bite angle ∠P–Rh–P of the intermediates I–VI was 8.7° in L1-system, as for L3-system, the variation was 14.0°. This structural feature might make the olefin-insertion and the CO-insertion occur more easily in the L1-system and resulted in higher aldehyde selectivity.

Hydroformylation of 2,5-norbornadiene in organic/aqueous two-phase system and acceleration by cationic surfactants

Co-reporter:Xi Yang;Haoran Liang;Haiyan Fu;Xueli Zheng;Maolin Yuan;Ruixiang Li

Applied Organometallic Chemistry 2016 Volume 30( Issue 5) pp:335-340

Publication Date(Web):

DOI:10.1002/aoc.3436

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.

An efficient and simple ligand from phthalandione for palladium-catalyzed Suzuki reaction in aqueous media

Co-reporter:Haiyang Liu, Hailong Liu, Ruixiang Li, Hua Chen

Tetrahedron Letters 2014 Volume 55(Issue 2) pp:415-418

Publication Date(Web):8 January 2014

DOI:10.1016/j.tetlet.2013.11.039

An efficient and simple ligand derived from phthalandione was used for palladium catalyzed Suzuki coupling reaction in water/ethanol (V/V = 2/1) under aerobic conditions. The reaction exhibited a high catalytic efficiency even with lower Pd loading (0.002 mol %). In this work, the catalyst could be successfully used in coupling reaction between various aryl halides with phenylboronic acid in excellent yields with high turnover number (TON) (the maximal TON was up to 49,000 for the reaction of bromobenzene with phenylboronic acid). Moreover, this new ligand had been elucidated by 1H NMR, 13C NMR and X-ray crystal diffraction.Ligand structure.

A highly efficient memantine-modified palladium catalyst for Suzuki–Miyaura cross-coupling reaction

Co-reporter:Qinxu Wu, Leilei Wu, Lei Zhang, Haiyan Fu, Xueli Zheng, Hua Chen, Ruixiang Li

Tetrahedron 2014 70(21) pp: 3471-3477

Publication Date(Web):

DOI:10.1016/j.tet.2014.03.064

Heterogeneous asymmetric hydrogenation of heteroaromatic methyl ketones catalyzed by cinchona-modified iridium catalysts

Co-reporter:Chun Li, Lin Zhang, Congye Zheng, Xueli Zheng, Haiyan Fu, Hua Chen, Ruixiang Li

Tetrahedron: Asymmetry 2014 Volume 25(10–11) pp:821-824

Publication Date(Web):31 May 2014

DOI:10.1016/j.tetasy.2014.04.013

A heterogeneous iridium catalyst was synthesized with silica particles as support for the hydrogenation of heteroaromatic methyl ketones. The catalyst and support were characterized by solid-state NMR, HTEM, SEM, XPS, and BET. A series of heteroaromatic methyl ketones were investigated at room temperature. The catalytic system was effective and more than 99% conversion and up to 83.6% enantioselectivity were obtained in the hydrogenation of heteroaromatic methyl ketones.The asymmetric hydrogenation of heteroaromatic methyl ketones catalyzed by an iridium heterogeneous catalyst with prepared monodispersed silica particles as support.

Synthesis, Characterization of N-Pyrrolylphosphanes Based on Heterocyclic Amine Backbones and Their Application in Hydroformylation of 1-Octene

Co-reporter:Lin Zhang;Chun Li;Xueli Zheng;Haiyan Fu;Ruixiang Li

Catalysis Letters 2014 Volume 144( Issue 6) pp:1074-1079

Publication Date(Web):2014 June

DOI:10.1007/s10562-014-1250-4

A new class of N-pyrrolylphosphanes based on new heterocyclic amines have been synthesized, characterized and applied in homogeneous rhodium-catalyzed hydroformylation of 1-octene. These ligands possessing strong π-acceptor properties effectively facilitate the olefin isomerization. The steric effect of ligands has also been examined. Large steric tetraphosphane ligand afforded better regioselectivity, and the L/B ratio of about 6.4 was obtained at low synthesis gas pressure (5 bar).

Organophilic worm-like ruthenium nanoparticles catalysts by the modification of CTAB on montmorillonite supports

Co-reporter:Limei Zhou, Xiaolong Qi, Xiaohui Jiang, Yafen Zhou, Haiyan Fu, Hua Chen

Journal of Colloid and Interface Science 2013 Volume 392() pp:201-205

Publication Date(Web):15 February 2013

DOI:10.1016/j.jcis.2012.10.019

A supported Ru catalyst was prepared by using cetyltrimethylammonium bromide (CTAB) intercalated montmorillonite as the supporting matrix. The as-prepared Ru catalyst was subsequently characterized by XRD, XPS, N2 sorption, TEM, and dispersibility measurement. The results showed that the Ru nanoparticles were in the modified montmorillonite interlayers, and the morphology of Ru nanoparticle was worm-like. Moreover, this supported Ru catalyst could be well dispersed in organic solvents such as toluene. The catalyst exhibited high activity and selectivity in the hydrogenation of quinoline even without stirring.Graphical abstractHighlights► Organophilic supported Ru catalysis was prepared. ► The CTAB intercalated montmorillonite was used as support. ► Worm-like Ru nanoparticles are distributed on the support. ► Catalyst was used in the hydrogenation of quinoline. ► It showed high activity and selectivity even without stirring.

Rhodium/bisphosphite catalytic system for hydroformylation of styrene and its derivatives

Co-reporter:Cong-ye Zheng;Min Mo;Hao-ran Liang;Xue-li Zheng;Hai-yan Fu;Mao-lin Yuan;Rui-xiang Li

Applied Organometallic Chemistry 2013 Volume 27( Issue 8) pp:474-478

Publication Date(Web):

DOI:10.1002/aoc.3009

Different kinds of mono- and bidentate phosphite ligands were used in Rh-catalyzed hydroformylation of styrene to illustrate the influence of steric and electronic properties of ligands on catalytic performance. High activity (99.9%) and good regioselectivity (85.4%) to the linear aldehyde were achieved under optimum conditions in the presence of Rh/bisphosphite complex (bisphosphite: 2,2′-bis(dipyrrolylphosphinooxy)-1,1′-(±)-binaphthyl). This system makes it possible to prepare functionalized terminal aldehydes from readily available styrene or its derivatives through hydroformylation with high linear selectivity. Copyright © 2013 John Wiley & Sons, Ltd.

Palladium-catalyzed selective decarboxylative coupling reaction versus direct CH arylation for arylation of heteroaromatics

Co-reporter:Haiyan Fu;Henri Doucet

Applied Organometallic Chemistry 2013 Volume 27( Issue 10) pp:595-600

Publication Date(Web):

DOI:10.1002/aoc.3037

Conditions for selective palladium-catalyzed decarboxylative 2-arylation of 3-substituted thiophene and furan derivatives bearing an ester at C2 position have been established. By using 2 mol% phosphine-free Pd(OAc)₂ as the catalyst and a mixture of KOH and K₂CO₃ as the bases, in dimethylacetamide, moderate to good yields of the desired 2-arylated products were obtained. A range of functional groups such as nitrile, nitro, formyl or acetyl on the aryl bromides was tolerated. This method allows us to employ in some cases more convenient reactants in terms of cost or physical properties (boiling point) for arylations. Copyright © 2013 John Wiley & Sons, Ltd.

Interaction between water-soluble rhodium complex RhCl(CO)(TPPTS)2 and surfactants probed by spectroscopic methods

Co-reporter:Li-Mei Zhou, Cai-Hong Guo, Hai-Yan Fu, Xiao-Hui Jiang, Hua Chen, Rui-Xiang Li, Xian-Jun Li

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 2012 93() pp: 198-202

Publication Date(Web):

DOI:10.1016/j.saa.2012.02.108

Amide as an efficient ligand in the palladium-catalyzed Suzuki coupling reaction in water/ethanol under aerobic conditions

Co-reporter:Hai Yang Liu, Kun Wang, Hai Yan Fu, Mao Lin Yuan, Hua Chen, Rui Xiang Li

Chinese Chemical Letters 2011 Volume 22(Issue 6) pp:738-740

Publication Date(Web):June 2011

DOI:10.1016/j.cclet.2010.12.048

Amide, which is derived from proline and is inexpensive and air-stable, has been synthesized and characterized by 1H NMR, 13C NMR, and MS. It was found to be an efficient ligand in the palladium-catalyzed Suzuki cross-coupling reaction. In the Pd/amide catalytic system, aryl bromides can be coupled with phenylboronic acid in ethanol/water (1:2; v/v) in excellent yields even with a low Pd loading of 0.01 mol%. Moreover, the scope of the reaction is broad, and a wide variety of functional groups are tolerant.

Copper and amine free Sonogashira cross-coupling reaction catalyzed by efficient diphosphane–palladium catalyst

Co-reporter:Ting He, Lei Lei Wu, Xing Li Fu, Hai Yan Fu, Hua Chen, Rui Xiang Li

Chinese Chemical Letters 2011 Volume 22(Issue 10) pp:1175-1178

Publication Date(Web):October 2011

DOI:10.1016/j.cclet.2011.05.014

The commercially available diphosphane ligand MeO-BIPHEP was first investigated in the palladium-catalyzed Sonogashira reaction in the absence of copper and amine. The coupling of various aryl bromides and aryl chlorides with phenylacetylene gave moderate to excellent yields.

Enantioselective hydrogenation of acetophenone by (1S, 2S)-DPEN–Ru(II)Cl2(PPh3)2 encapsulated in Al-MCM-41

Co-reporter:Jian Hong Liu, Dong Liang, Bin Bin Fan, Rui Feng Li, Hua Chen

Chinese Chemical Letters 2010 Volume 21(Issue 7) pp:802-806

Publication Date(Web):July 2010

DOI:10.1016/j.cclet.2010.03.011

A chiral ruthenium complex [(1S, 2S)-DPEN]–RuCl2(PPh3)2 (DPEN = 1,2-diphenylethylenediamine, PPh3 = triphenylphosph-ine) was encapsulated in the channel of Al-MCM-41 by electrostatic adsorption and 1,1-dichlorosilacyclobutane modification. The prepared heterogeneous catalyst showed the same catalytic activity and enantioselectivity as the corresponding homogeneous catalyst in the asymmetric hydrogenation of acetophenone, and could be reused at least seven times without significant loss of catalytic activity and enantioselectivity.

Modification of montmorillonite surfaces using a novel class of cationic gemini surfactants

Co-reporter:Limei Zhou, Hua Chen, Xiaohui Jiang, Fang Lu, Yafen Zhou, Wenmin Yin, Xiaoyang Ji

Journal of Colloid and Interface Science 2009 Volume 332(Issue 1) pp:16-21

Publication Date(Web):1 April 2009

DOI:10.1016/j.jcis.2008.12.051

A novel class of cationic gemini surfactants were prepared and used as modifiers for sodium montmorillonite (MMT-Na). The modified montmorillonites were characterized by X-ray diffraction (XRD), thermal analysis (TG), Fourier transform infrared spectroscopy (FTIR), dispersibility measurement, and scanning electron microscopy (SEM). The results show that the surfactants have been intercalated into the montmorillonite layers successfully. XRD measurements indicate that the gemini surfactant is more effective at expanding the interlayer space of the MMT than the corresponding single chain surfactant. Moreover, the high efficiency can be obtained by lengthening the hydrophobic chains of gemini surfactants. Thermal analysis shows that there are four different molecular environments for gemini surfactants in the modified montmorillonite. The dispersibility measurement and SEM results indicate that the modified montmorillonite are more hydrophobic and prone to agglomerate in water than MMT-Na. These modified materials have the potential for removal of environment pollutants such as pesticides, phenol, etc. or being used as antimicrobial materials.Novel cationic gemini surfactants were synthesized and used as modifiers for sodium montmorillonite. XRD patterns indicate that the gemini surfactant is more effective at expanding the interlayer space of the MMT than the corresponding monomeric surfactant. Moreover, the high efficiency can be obtained by lengthening the hydrophobic chains of gemini surfactants.

Efficient Diphosphane-Based Catalyst for the Palladium-Catalyzed Suzuki Cross-Coupling Reaction of 3-Pyridylboronic Acids

Co-reporter:Xing-Li Fu;Lei-Lei Wu;Hai-Yan Fu, ;Rui-Xiang Li

European Journal of Organic Chemistry 2009 Volume 2009( Issue 13) pp:2051-2054

Publication Date(Web):

DOI:10.1002/ejoc.200900038

Abstract

A highly active catalyst system derived from PdCl₂ and2,2′,6,6′-tetramethoxy-4,4′-bis(diphenylphosphanyl)-3,3′-bipyridine (P-Phos) has been developed for the Suzuki cross-coupling reaction of pyridylboronic acid with a variety of aryl halides in good to excellent yields, even in the presence of hindered and functional groups. In addition, P-Phos also exhibited high activity in the palladium-catalyzed Suzuki reaction of 2,6-dimethoxypyridylboronic acid in excellent yields with a fast rate. The steric and electronic effects of the P-Phos–palladium complex to this cross-coupling reaction were also discussed.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Asymmetric hydrogenation of acetophenone catalyzed by cinchonidine stabilized Ir/SiO2

Co-reporter:ChaoFen Yang, HeYan Jiang, Jian Feng, HaiYan Fu, RuiXiang Li, Hua Chen, XianJun Li

Journal of Molecular Catalysis A: Chemical 2009 300(1–2) pp: 98-102

Publication Date(Web):

DOI:10.1016/j.molcata.2008.10.041

Enantioselective Hydrogenation of Aromatic Ketones Catalyzed by Ru Complex Using a New Bipyridyl Diphosphine

Co-reporter:Li CHEN;Xing-Li FU;Fang-Yong MING;Xian-Jun LI

Chinese Journal of Chemistry 2008 Volume 26( Issue 2) pp:353-357

Publication Date(Web):

DOI:10.1002/cjoc.200890068

Abstract

A series of RuCl₂(bipyridyldiphosphine)(1,2-diamine) complexes were synthesized and applied to the asymmetric hydrogenation of aromatic ketones. Solvent effect and a wide variety of aromatic ketones were explored and up to 96% enantioselectivity was achieved in the hydrogenation of o-bromoacetophenone.

Heterogeneous Enantioselective Hydrogenation of Aromatic Ketones Catalyzed by Cinchona- and Phosphine-Modified Iridium Catalysts

Co-reporter:He-yan Jiang;Chao-fen Yang;Chun Li;Hai-yan Fu, ;Rui-xiang Li ;Xian-jun Li

Angewandte Chemie 2008 Volume 120( Issue 48) pp:9380-9384

Publication Date(Web):

DOI:10.1002/ange.200801809

Application of a new amphiphilic phosphine in the aqueous biphasic catalytic hydroformylation of long chain olefins

Co-reporter:Haiyan Fu, Min Li, Jun Chen, Ruimin Zhang, Weidong Jiang, Maolin Yuan, Hua Chen, Xianjun Li

Journal of Molecular Catalysis A: Chemical 2008 Volume 292(1–2) pp:21-27

Publication Date(Web):17 September 2008

DOI:10.1016/j.molcata.2008.06.005

The preparation of a new surface-active sulfonated phosphine and its catalytic performance in aqueous biphasic hydroformylation of long chain olefins were reported. The amphiphilic phosphine: sodium salt of sulfonated n-C12H25O C6H4P(C6H4-p-CH3O)2 (DMOPPS) was prepared by sulfonation of the hydrophobic phosphine DMOPP in concentrated H2SO4 under N2 atmosphere at 30 °C for about 5 h. The rhodium complex, RhCl(CO)(TPPTS)2 [TPPTS =P(C6H4-m-SO3Na)3], was used as the catalyst precursor. The catalytic active species with the DMOPPS as ligand was in situ formed by adding DMOPPS to the RhCl(CO)(TPPTS)2 catalyst precursor. The surface-activity and micelle-forming property of this new amphiphilic phosphine were confirmed by using cryogenic transmission electron microscope (Cryo-TEM). Under the same conditions, the biphasic hydroformylation of 1-decene using DMOPPS as ligand was compared with that using traditional TPPTS as ligand. The catalysis system using DMOPPS was also compared with the previous Rh-TPPTS-surfactant [C12H25N(CH3)3I (DTAI)] system. Some reaction parameters such as stirring rates, alkyl chain length of olefins, the molar ratio of phosphine/rhodium, and the catalyst recycle were also studied in detail. The results showed that the ligand DMOPPS exhibited a micelle-forming property that could significantly enhance the hydroformylation reaction rate of long chain olefin. Moreover, the surface-active phosphine may also stabilize the aqueous/oil phase boundary, which could enhance the biphasic catalytic reaction rates.The preparation of a new surface-active phosphine-sodium salt of sulfonated n-C12H25OC6H4P(C6H4-p-CH3O)2 (DMOPPS) and its application in the aqueous biphasic catalytic hydroformylation of long chain olefins were reported. The ligand exhibits a surface-active property which could significantly enhance the reaction rate. Compared with previous RhCl(CO)(TPPTS)2–TPPTS-surfactant system, the RhCl(CO) (TPPTS)2–DMOPPS system shows better catalytic performances.

Heterogeneous Enantioselective Hydrogenation of Aromatic Ketones Catalyzed by Cinchona- and Phosphine-Modified Iridium Catalysts

Co-reporter:He-yan Jiang;Chao-fen Yang;Chun Li;Hai-yan Fu, ;Rui-xiang Li ;Xian-jun Li

Angewandte Chemie International Edition 2008 Volume 47( Issue 48) pp:9240-9244

Publication Date(Web):

DOI:10.1002/anie.200801809

Asymmetric hydrogenation of α,β-unsaturated ketones catalyzed by Ru–TPPTS–(S,S)-DPENDS complex in ionic liquids

Co-reporter:Jinbo Wang, Ruixiang Qin, Haiyan Fu, Jun Chen, Jian Feng, Hua Chen, Xianjun Li

Tetrahedron: Asymmetry 2007 Volume 18(Issue 7) pp:847-851

Publication Date(Web):30 April 2007

DOI:10.1016/j.tetasy.2007.03.021

The asymmetric hydrogenation of α,β-unsaturated ketones catalyzed by the achiral ruthenium monophosphine complex RuCl2(TPPTS)2 [TPPTS: P(m-C6H4SO3Na)3] modified by (S,S)-DPENDS [disodium salt of sulfonated (S,S)-1,2-diphenyl-1,2-ethylene-diamine] was investigated in ionic liquid [RMIM]Ts (1-alkyl-3-methylimidazolium p-methylphenylsulfonates, R = ethyl, butyl, octyl, dodecyl). Chemoselectivity of 100% and 75.9% ee were obtained for benzalacetone under the optimized conditions. The resulting products can be easily separated from the catalyst immobilized in ionic liquid [EMIM]Ts by extraction with n-hexane, while the catalyst can be reused seven times without the loss of catalytic activity and enantioselectivity. Especially, the addition of water can improve the performance of the catalyst.

Asymmetric hydrogenation of aromatic ketones catalyzed by achiral monophosphine TPPTS-stabilized Ru in ionic liquids

Co-reporter:Jinbo Wang, Jian Feng, Ruixiang Qin, Haiyan Fu, Maolin Yuan, Hua Chen, Xianjun Li

Tetrahedron: Asymmetry 2007 Volume 18(Issue 14) pp:1643-1647

Publication Date(Web):30 July 2007

DOI:10.1016/j.tetasy.2007.07.016

Achiral monophosphine TPPTS [TPPTS: P(m-C6H4SO3Na)3]-stabilized Ru was synthesized by reduction of RuCl3·3H2O with hydrogen in ethanol using TPPTS as the stabilizer. The catalytic asymmetric hydrogenation of aromatic ketones using TPPTS-stabilized Ru modified by a chiral diamine (1R,2R)-DPENDS [disodium salt of sulfonated (1R,2R)-1,2-diphenyl-1,2-ethylene-diamine] was investigated in hydrophilic ionic liquid [RMIM]Ts (1-alkyl-3-methylimidazolium p-methylphenylsulfonates, R = ethyl, butyl, octyl, dodecyl, hexadecyl). Hundred percent conversion and 85.1% ee were obtained for acetophenone under optimized conditions. The resulting products can be easily separated from the catalyst immobilized in ionic liquid by simple extraction with n-hexane, and the catalyst can be reused several times without a significant loss of ee value or conversion. In particular, the addition of water can improve the catalyst performance.(S)-(−)-1-PhenylethanolC8H10OEe = 80.3%[α]D28=-23.2 (c 1.08, CH2Cl2)Source of chirality:asymmetric hydrogenationAbsolute configuration:(S)(S)-(−)-1-PhenylpropanolC9H12OEe = 80.0%[α]D28=-39.5 (c 1.52, C2H5OH)Source of chirality:asymmetric hydrogenationAbsolute configuration:(S)(S)-(−)-1-(2′-Fluorophenyl)ethanolC8H9OFEe = 54.3%[α]D28=-35.7 (c 1.26, CHCl3)Source of chirality:asymmetric hydrogenationAbsolute configuration:(S)(S)-(−)-1-(2′-Chlorophenyl)ethanolC8H9OClEe = 77.3%[α]D28=-29.5 (c 1.76, CHCl3)Source of chirality:asymmetric hydrogenationAbsolute configuration:(S)(S)-(−)-1-(2′-Bromophenyl)ethanolC8H9OBrEe = 82.7%[α]D28=-31.3 (c 1.60, CHCl3)Source of chirality:asymmetric hydrogenationAbsolute configuration:(S)(R)-(+)-1-(2′-Methoxyphenyl)ethanolC9H12O2Ee = 45.4%[α]D28=+33.3 (c 1.05, CHCl3)Source of chirality:asymmetric hydrogenationAbsolute configuration:(R)(S)-(−)-1-(4′-Methoxyphenyl)ethanolC9H12O2Ee = 76.5%[α]D28=-29.1 (c 1.03, CHCl3)Source of chirality: asymmetric hydrogenationAbsolute configuration: (S)(S)-(−)-1-(4′-Trifluoromethylphenyl)ethanolC9H9OF3Ee = 58.7%[α]D28=-39.0 (c 1.41, CH3OH)Source of chirality: asymmetric hydrogenationAbsolute configuration: (S)

Synthesis of New MeO-BIPHEP-type Chiral Diphosphines by an Improved Way

Co-reporter:Meng-Lin Ma;Zong-Hai Peng;Li Chen;Yu Guo;Xian-Jun Li

Chinese Journal of Chemistry 2006 Volume 24(Issue 10) pp:

Publication Date(Web):2 OCT 2006

DOI:10.1002/cjoc.200690260

In this paper, a series of new optically active MeO-BIPHEP-type ligands, (S)-6,6′-dimethoxy-2,2′-bis(di- p-alkoxyphenyl-phosphine)-1,1′-biphenyl [(S)-5b–(S)-5e] were prepared and characterized. Starting from the commercially available triethyl phosphorite and m-bromoanisole, an optically active (S)-6,6′-dimethoxybiphenyl- 2,2′-diyl-bis(phosphonic acid diester) was prepared by an improved way and converted to the corresponding dichlorides, which was used as a key intermediate to react with p-alkoxybenzenemagnesium bromide or p-alkoxyphenyl lithium to directly give the enantiomerically pure diphosphines 5.

Carbonylation of Aryl Halide Catalyzed by Active-carbon Supported Ionic Liquid-phase Palladium Catalyst

Co-reporter:Qi Lin, Haiyan Fu, Maolin Yuan, Hua Chen, Xianjun Li

Acta Physico-Chimica Sinica 2006 Volume 22(Issue 10) pp:1272-1276

Publication Date(Web):October 2006

DOI:10.1016/S1872-1508(06)60062-4

Highly dispersed supported ionic liquid-phase palladium catalyst was prepared and its catalytic performances for carbonylation of aryl halide were investigated. Active-carbon supported ionic liquid-phase palladium catalyst was characterized by XRD, high-resolution TEM (HRTEM), and XPS. The results showed that the active-carbon supported ionic liquid-phase palladium catalyst was reduced to zero valence and that the average particle diameter of the Pd crystallites was less than 5 nm. A thin ionic liquid film was observed on the surface of the catalyst. The results indicated that the supported ionic liquid-phase palladium catalyst exhibited higher activity in the carbonylation of aryl halides compared with the corresponding organic-ionic liquid biphasic system. Under the optimum reaction conditions: 140 °C, pCO = 4.0 MPa, n(PhI):n(Pd) = 10528:1, the turnover frequency (TOF) of 4926 h−1 was achieved for ethyl benzoate with the conversion of 99.3%, and the selectivity for forming ethyl benzoate was more than 99%.

Interaction between water-soluble rhodium complex RhCl(CO)(TPPTS)2 and surfactants probed by spectroscopic methods

Co-reporter:Li-Mei Zhou, Cai-Hong Guo, Hai-Yan Fu, Xiao-Hui Jiang, Hua Chen, Rui-Xiang Li, Xian-Jun Li

Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy (July 2012) Volume 93() pp:198-202

Publication Date(Web):1 July 2012

DOI:10.1016/j.saa.2012.02.108

The interactions of rhodium complex RhCl(CO)(TPPTS)2 [TPPTS = P(m-C6H4SO3Na)3] with cationic, nonionic, and anionic surfactants have been investigated by UV–vis, fluorescence and 1H NMR measurements. The presence of four different species of RhCl(CO)(TPPTS)2 in cationic cetyltrimethylammonium (CTAB) solution has been demonstrated: free rhodium complex, rhodium complex bound to CTAB monomer, rhodium complex bound to CTAB premicelles, rhodium complex bound to CTAB micelles. The spectroscopy data show that RhCl(CO)(TPPTS)2 can adsorb on the interface of cationic CTAB micelles by strong electrostatic attraction, weakly bind to the nonionic polyoxyethylene (20) sorbitan monolaurate (Tween 20) micelles by hydrophobic interaction, and does not interact with anion sodium dodecyl sulfate (SDS) micelles due to the strong electrostatic repulsion.Graphical abstractDownload full-size imageHighlights► UV–vis, fluorescence and 1H NMR were used to investigate the interaction between surfactants and water-soluble rhodium complex. ► Fluorescence spectrometry was firstly used to investigate this system. ► A possible interaction mechanism of water-soluble rhodium complex with cationic surfactants was proposed.

Catalytic transfer hydrogenolysis of α-methylbenzyl alcohol using palladium catalysts and formic acid

Co-reporter:Jian Feng, Chaofen Yang, Dinglin Zhang, Jinbo Wang, Haiyan Fu, Hua Chen, Xianjun Li

Applied Catalysis A: General (15 February 2009) Volume 354(Issues 1–2) pp:38-43

Publication Date(Web):15 February 2009

DOI:10.1016/j.apcata.2008.11.008

Cinchona-modified Ru catalysts for enantioselective heterogeneous hydrogenation of aromatic ketones

Co-reporter:He-yan Jiang, Hua Chen, Rui-xiang Li

Catalysis Communications (10 March 2010) Volume 11(Issue 7) pp:584-587

Publication Date(Web):10 March 2010

DOI:10.1016/j.catcom.2009.12.024

In this communication, we describe the highly enantioselective heterogeneous hydrogenation of aromatic ketones catalyzed by Ph3P stabilized Ru/γ-Al2O3, and modified by chiral diamines derived from cinchona alkaloids. A broad range of aromatic ketones over this catalyst can be hydrogenated to the corresponding alcohols with impressive enantioselectivity.