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崔新江,石峰,邓友全
283.07 KB

The N-alkylation of sulfonamides with alcohols is efficiently performed in the presence of easily available copper catalysts via hydrogen borrowing methodology. Applying a copper acetate/potassium carbonate system the reaction of sulfon-ACHTUNGTRENUNGamides and alcohols gave the corresponding secondary amines in excellent yield. In situ HR-MS analysis indicated that bissulfonylated amines are formed under air atmosphere, which act as self-stabilizing ligands for the catalytic system. UV-visible measurements suggest the interaction between the copper centre and the bissulfonylated amine. Reactions of benzyl alcohol-d7 with p-toluenesulfonamide, Nbenzyl-p-toluenesulfonamide or N-benzylidenetolu-ACHTUNGTRENUNGenesulfonamide revealed that the reaction proceeds via a transfer hydrogenation mechanism and the whole process is micro-reversible. Competitive reactions of benzyl alcohol and benzyl alcohol-d7 with ptoluenesulfonamide revealed a kinetic isotope effect (kH/kD) of 3.287 (0.192) for the dehydrogenation of benzyl alcohol and 0.611 (0.033) for the hydrogenation of the N-benzylidene-p-toluACHTUNGTRENUNGenesulfonamide intermediate, which suggests that dehydrogenation of the alcohol is the rate-determining step.

Keywords: alcohols; alkylation; CN bond formation; copper catalysts; sulfonamides

★★★☆☆ Cui XJ,Shi F,Man Kin Tes,et al. Copper-catalyzed N-alkylation Of Sulfonamides With Benzylic Alcohols: Catalysis And Mechanistic Studies[J]. Adv. Synth. Catal.,2009,351:2949-2958.

石峰 / 邓友全
142.95 KB

Based on the diversity of ionic liquids, i.e. tunable structure and physicochemical properties, a series of functional ionic liquids and palladium complexes were investigated, and a highly effective catalyst system, Pd(phen)Cl2-BAcImPF6 ionic liquid (phen = 1,10-phenanthroline; BAcIm = 1-butyl-3-acetic acid-imidazolium), was developed for the reductive carbonylation of nitrobenzene to give the corresponding carbamate with higher than 90% of conversion and selectivity at 150 ◦C and 6MPa carbon monoxide. The high catalytic performance is attributed to the acidic function of the BAcImPF6 ionic liquid and the interaction between Pd(phen)Cl2 and the ionic liquid to form the catalytically active palladium complex Pd(phen)2(PF6)2.

Keywords: Nitrobenzene; Carbon monoxide; Carbonylation; Ionic liquids; Palladium complex

★★★☆☆ Shi F,He YD,Li DM,et al. Developing Effective Catalyst System For Reductive Carbonylation Of Nitrobenzene Based On The Diversity Of Ionic Liquids[J]. Journal Of Molecular Catalysis A: Chemical,2006,244:64-67.

石峰 / 邓友全
283.00 KB

A new kind of silica gel confined ionic liquid containing a metal complex as heterogenized catalysts was prepared for the carbonylation of amines and nitrobenzene without molecular oxygen to afford the corresponding ureas with greatly enhanced catalytic activity (TOF exceeded 11000mol.mol(-1). h(-1)), with a much lower amount of ionic liquids being needed, with easy catalyst separation and possible reusability, and avoidance of the using of explosive CO + O-2 gas mixtures. Such an enhancement in catalytic activity may be derived from the effect of a high concentration of ionic liquid containing a metal complex due to the confinement into the nanopores or cavities of the silica gel matrix.

★★★☆☆ Keywords: amines; carbonylation; ionic liquids; nitrobenzene; phosgene-free

★★★☆☆ Adv. Synth. Catal. 2005, 347, 225 –230.

石峰 / 邓友全
160.60 KB

★★★★★ J. AM. CHEM. SOC. 2005, 127, 4182-4183. ★★★★★

石峰 / 邓友全
243.68 KB

A new concept of designing and synthesizing highly dispersed ionic-liquid catalysts was developed through physical confinement or encapsulation of ionic liquids (with or without metal complex) in a silica-gel matrix through a sol-gel process. We studied ionic liquids such as EMImBF4, BuMImBF4, DMImBF4, CMImBF4, BuMImPF6, either with or without [Pd(PPh3)2Cl2] and [Rh(PPh3)3Cl], in a silica-gel matrix (E=ethyl, Bu=butyl M=methyl, D=decyl, C=cetyl and Im=imidazolium). The contents of ionic liquids and loadings of Pd or Rh were 8-53 wt % and 0.10.15 wt %, respectively. Analyses of FT-Raman spectra showed that abnormal Raman spectra of the confined ionic liquids were observed in comparison with the bulk and pure ionic liquids. EMImBF4 and BuMImBF4 ionic liquids could be completely washed out from the silica-gel matrix under vigorous reflux conditions, but ionic liquids with larger molecular size, for example, DMImBF4 or CMImBF4, could be confined into the silica-gel nanopores relatively firmly. These results suggested that the ionic liquids were physically confined or encapsulated into the silica gel. The N2 adsorption measurements indicated that the silica-gel skeleton was mesoporous with 50-110 ? pore size after the BuMImBF4 ionic liquid was removed completely. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis showed that the silica-gel matrix was amorphous and non-uniformly mesoporous. Carbonylation of aniline and nitrobenzene for synthesis of diphenyl urea, carbonylation of aniline for synthesis of carbamates, and oxime transformation between cyclohexanone oxime and acetone were used as test reactions for these catalysts. Catalytic activities were remarkably enhanced with much lower amounts of ionic liquids needed with respect to bulk ionic-liquid catalysts or silica-supported ionic-liquid catalysts prepared with simple impregnation, in which the ionic liquid may be deposited as a thin layer on the support. Such unusual enhancement in catalytic activities may be attributed to the formation of nanoscale and high-concentration ionic liquids due to the confinement of the ionic liquid in silica gel; this results in unusual changes in the symmetry and coordination geometry of the ionic liquids.

★★★★☆ Keywords: carbonylation · catalysis· ionic liquids · nanotechnology ·synthesis design

★★★★☆ Chem. Eur. J. 2005, 11, 5279 – 5288

石峰 / 邓友全
223.09 KB

A new concept of designing and synthesizing highly dispersed ionic liquids was developed through physical confinement or encapsulation of them into silica gel matrix with sol–gel process. A series of silica gel confined ionic liquids were synthesized through this process and characterized by diffuse-reflectance infrared Fourier transform spectroscopy (DRIFTS) and FTRaman analysis, and abnormal FT-IR and FTRaman spectra were observed. The silica gel matrixes confined ionic liquid BMImBF4 were further characterized by BET analysis after the ionic liquid was almost completely washed out by acetone under refluxing conditions and meso-porous silica gel matrixes were obtained according to the N2 adsorption measurements, which suggested that the particle-size of the dispersed ionic liquids was in nano-scale. In consideration of the results obtained together, it could be found that the abnormal FT-IR and FTRaman spectra were changed with the poresize of the silica gel matrix. For example, obvious abnormal FT-IR and FTRaman spectra appeared when the particle-size of ionic liquid BMImBF4 is smaller than 11 nm while they disappeared again if the corresponding particle-size >11 nm. These results indicated that nano-effect, or restriction effect, produced from the nano-pores of silica gel was the reason for the abnormal FT-IR and FTRaman spectra.

★★★☆☆ Keywords: Ionic liquids; Silica gel; Abnormal spectra; Nano-material; Characterization

★★★☆☆ F. Shi, Y. Deng / Spectrochimica Acta Part A 62 (2005) 239–244.

石峰 / 邓友全
163.43 KB

A brief review of the work carried out at Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences for development of ionic liquid as green reaction media and catalysts is presented. This includes the processes of ionic liquid to be used as catalyst, reaction media, development of functional ionic liquid and methods for synthesis of immobilized ionic liquid. In the end, some prospects for development of ionic liquid are also addressed.

★★★☆☆ KEY WORDS: catalysis; green chemistry; ionic liquid; reaction media; review.

★★★☆☆ F. Shi et al./ Catalysis Surveys from Asia, 2004, 8(3): 179-186.

石峰 / 邓友全
209.51 KB

A highly efficient catalyst system, palladium complex–ionic liquid, was developed for the carbonylation of amines to give carbamate or urea. The desired products could be precipitated by adding water into the resulting mixture and the catalyst system could be reused with slight loss of catalytic activity.

★★★☆☆ F. Shi et al. / Journal of Catalysis 219 (2003) 372–375.

石峰 / 邓友全
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Methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), and isopropyl tert-butyl ether (IPTBE) have been synthesized for the first time over a non-acid ionic liquid as catalyst and dehydrator with high conversion ( > 90%) and selectivity ( > 90%) under mild conditions.

★★★★☆ Feng Shi, Hai Xiong, Yanlong Gu, Shu Guo and Youquan Deng. CHEM. COMMUN. , 2003, 1054–1055.

石峰 / 邓友全
112.67 KB

★★★★★ Feng Shi, Youquan Deng,* Tianlong SiMa, Jiajian Peng, Yanlong Gu, and Botao Qiao. Angew. Chem. Int. Ed. 2003, 42, 3257–3260. ★★★★★