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1.
Asymmetric sulfoxidation of phenacyl phenyl sulfide was performed in the presence of bis(acetylacetonanto) oxovanadium(IV) complexes with chiral Schiff bases, which were generated in situ. Chlorine dioxide and hydrogen peroxide as oxidants were compared.  相似文献   

2.
全氟烷基磺酰亚胺配合物及其催化应用   总被引:4,自引:2,他引:2  
袁余斌  聂进 《有机化学》2004,24(8):857-863
介绍了全氟烷基磺酰亚胺(PFSI)配合物的结构、性质及制备,综述了一些全氟烷基磺酰亚胺配合物作为Lewis酸催化剂的最新应用进展,并对其催化应用前景进行了展望.  相似文献   

3.
An efficient synthesis of 4-aminotropones has been achieved in excellent yields by simple treatment of 4-amino-4-[(p-tolylsulfinyl)methyl]-2,5-cyclohexadienones (p-quinamines) with NaH. The method allowed regiocontrolled access to 3-methyl, 5-methyl- and 3,5-dimethyl-substituted derivatives starting from p-quinamines with adequate substituents at the cyclohexadienone moiety and/or at the carbon linked to the sulfur function. The p-quinamines in turn were easily accessible from N-Boc p-anisidines (Boc=tert-butoxycarbonyl) by electrochemical oxidation in MeOH to quinone imine monoketals, followed by addition of a alpha-lithium sulfinyl carbanion to the imino group, and ketal hydrolysis. Oxidation of the sulfoxide gave the sulfonyl-substituted p-quinamines that, upon basic treatment, behave similarly. The p-quinamine 55 and bis-p-quinamine 56, resulting in the addition of the anion derived from dimethyl sulfone to the p-quinonimine ketal 14, also gave the 4-aminotropone. The mechanism involves the initial formation of a alpha-sulfonyl carbanion, which intramolecularly attacks the cyclohexadienone giving a norcaradiene-like enolate intermediate, the evolution of which through a ring-expansion process, pushes off a methyl sulfinate anion or SO2. This efficient process fulfils the criteria of atom economy. The introduction of a proline substituent in the nitrogen of the starting p-quinamine allowed the synthesis of an enantiopure 4-aminotropone, the asymmetric Diels-Alder reactions of which with maleimide occurred in a highly endo and pi-facial diastereoselective manner.  相似文献   

4.
2-[(4-羟基苯基)砜基]苯酚的合成及其精制新工艺; [(羟基苯基)砜基]苯酚;苯酚;亚磷酸;偏三甲苯  相似文献   

5.
研究了钌-双膦-二胺配合物催化剂RuC1_2[(S)-P-Phos]-[(S)-DAIPEN][P-Phos:2,2',6,6'-四甲氧基-4,4'-双(二苯基膦基)-3,3'.二吡啶,DA肫N:1,1.二(4.甲氧苯基).2.异丙基.1,2.乙二胺]催化芳香酮不对称加氢反应的性能,考察了不同的碱、叔丁醇钾浓度、反应溶剂、底物/催化剂摩尔比等因素对反应活性和对映选择性的影响.在苯乙酮、叔丁醇钾、催化剂的摩尔比为1000:20:1,氢气压力为2 MPa,反应温度为30℃时,苯乙酮的转化率和α-苯乙醇的对映选择性(ee)分别达到了100%和88.5%,2'-溴苯乙醇的ee值町达97.1%.  相似文献   

6.
7.
2-[(3-Aminophenyl)sulfonyl] ethanol hydrogen sulfate (APSES) is an important intermediate for reactive dyes.It can be used to synthesize KN type reactive dyes, which have broad colour spectra,good water solubility, excellent adaptability for different dye technique,etc. Synthesis of APSES were currently developed by Kato Kuniok et al[1] and Sanki[2].Kato had attempted to synthesize of APSES by reaction of sodium benzenesulfinate as raw material with ethylene oxide to obtain 2-phenylsulfonyl ethanol(PSE). The PSE could further be nitrated and hydrogenated to obtain 2-[(3-aminophenyl)sulfonyl]ethanol (APSE). Finally,APSE was reacted with oleum to obtain 2-[(3-aminophenyl) sulfonyl] ethanol hydrogen sulfate (APSES). Sanki had discoved a new synthetic method for the PSE. The PSE was prepared by first reaction of thiophenol as raw material with chloroethanol, and then by oxidation with hydrogen peroxide.The above mentioned two methods are not easily be adopted in industries at home. The shortage and cost of the thiophenol and sodium benzenesulfinate are mainly limited. We modificated a new synthetic pathway for APSES by five steps. The experimental procedures are shown the following.  相似文献   

8.
Neutron diffraction has been used to determine the liquid structure of 1,3-dimethylimidazolium bis[(trifluoromethyl)sulfonyl]amide ([dmim][NTf2]). Significantly smaller charge ordering is found in this liquid compared with analogous chloride and hexafluorophosphate salts due to the diffuse charge density and size of the [NTf2]- anion. This is manifested in a much larger cation-cation and cation-anion separation and an overlap of the cation-cation and cation-anion shells. Comparison of the liquid structure with the crystal structure reported by Holbrey et al. (Dalton Trans. 2004, 2267) indicates little correlation, for example, the [NTf2]- anion adopts a trans orientation predominantly in the liquid whereas a cis orientation is found in the solid phase.  相似文献   

9.
10.
A series of four different dilithium salts of structure F3CSO2N(Li)SO2-(CF2)x-SO2N(Li)SO2CF3, with x = 2, 4, 6, 8 were synthesized and characterized in polyethylene-oxide-based solid polymer electrolytes. Each salt may be thought of as two bis[(perfluoroalkyl)sulfonyl]imide anions linked together by a perfluoroalkyl chain of a particular length. Taken together, this homologous series provides an opportunity to study the effects of linker chain length and degree of fluorination in dianionic (and ultimately polyanionic) salts on the properties, particularly the conductivity, of the salts in various solvating media. SPEs in polyethylene oxide were characterized using scanning calorimetry, X-ray diffraction, 1H and 19F NMR, and electrochemical impedance spectroscopy for SPEs prepared using ethylene-oxide-oxygen-to-lithium (EO:Li) ratios of 10:1 and 30:1. Trends in SPE ionic conductivity with anion structure revealed an unexpected trend whereby ionic conductivity is generally rising with increased length of the perfluoroalkylene linking group in the dianions. This trend could be the result of a decrease in dianion basicity that results in diminished ion pairing and an enhancement in the number of charge carriers with increasing anion fluorine content, thereby increasing ionic conductivity.  相似文献   

11.
制备了功能化离子液体1-丁腈-3-甲基咪唑双三氟甲基磺酸亚胺。在T为283.15-353.15 K温度范围内,测定了该功能化离子液体的密度、动力粘度、电导率及折光率。讨论了亚甲基的增减对该类功能化离子液体的密度、动力粘度、电导率及折光率等性质的影响,并与传统咪唑类、吡啶类离子液体物理化学性质的变化趋势进行了对比。通过经验方程计算了该功能化离子液体的热膨胀系数、分子体积、标准摩尔熵及晶格能等热力学性质参数。讨论了Vogel-Fulcher-Tamman (VFT)方程和Arrhenius方程的适用性,得出VFT方程适用于该功能化离子液体,而Arrhenius方程并不适用。有关研究对新型离子液体的合成及其工业化的应用具有十分重要的意义。  相似文献   

12.
研究了钌-双膦-二胺配合物催化剂RuCl2[(S)-P-Phos]-[(S)-DAIPEN] [P-Phos: 2,2',6,6'-四甲氧基-4,4'-双(二苯基膦基)-3,3'-二吡啶, DAIPEN: 1,1-二(4-甲氧苯基)-2-异丙基-1,2-乙二胺]催化芳香酮不对称加氢反应的性能, 考察了不同的碱、叔丁醇钾浓度、反应溶剂、底物/催化剂摩尔比等因素对反应活性和对映选择性的影响. 在苯乙酮、叔丁醇钾、催化剂的摩尔比为1000:20:1, 氢气压力为2 MPa, 反应温度为30 ℃时, 苯乙酮的转化率和α-苯乙醇的对映选择性(ee)分别达到了100%和88.5%, 2'-溴苯乙醇的ee 值可达97.1%.  相似文献   

13.
A new, practical and cost-effective route for scalable synthesis of 2-[(4-dodecyloxyphenyl)sulfonyl] butanoic acid, a key intermediate of a new cyan dye-forming coupler containing a sulfone group, was developed by adopting phenol as the starting material. The synthesis was accomplished in five steps with etherification, chlorosulfonation, reduction, nucleophilic reaction by C-S coupling and hydrolyzation. An important objective of the new synthetic route was the synthesis of 2-[4-(dodecyloxyphenyl)sulfonyl]butanoate. Overall yield obtained at optimized conditions increased to 66 %. The synthetic strategy was proven to be a process enabling rapid delivery of the target product with high purity.  相似文献   

14.
The facile preparation and characterization on a novel trisodium salt based on bis[(perfluoroalkyl)sulfonyl]triimide trianion were reported for the first time. High oxidation potential was observed for the new salt in organic solvent. Ionic conductivities of this new salt and other monomeric sodium salts were determined in different organic solvents over a temperature range between 10 and 100 °C.  相似文献   

15.
Neutral copper complexes of the deprotonated [(4-methylphenyl)sulfonyl]-1H-imino-(2-phenyl-2-oxazoline) proligands, [HTs-ROz], R = H, 5-Me, 4-Me, 4-Et, 4-iPr, have been prepared by electrochemical oxidation of anodic copper in an MeCN solution of the corresponding proligand. The [Cu(Ts-ROz)2] complexes were characterised by microanalysis, i.r. and electronic spectroscopies, and by e.p.r. and magnetic measurements. The crystal structures of HTs-5MeOz, [Cu(Ts-Oz)2], [Cu(Ts-5MeOz)2] and [Cu(Ts-4MeOz)2] were determined by X-ray diffraction.  相似文献   

16.
17.
Bis[(perfluoroalkyl)sulfonyl]imides [HN(SO2Rf)2, and Rf represents the perfluorinated alkyl group] supported on MCM-41 were synthesized and characterized by XRD, FTIR, SEM, TGA and N2-adsorption techniques. The supported catalysts, HN(SO2Rf)2/MCM-41, were used as the catalysts for the tert-butylafion of hydroquinone (HQ) with tert-butyl alcohol (TBA) in the liquid phase. A high yield (52.0%) of 2-tert-butyl hydroquinone (TBHQ) could be obtained in the presence of 5 tool% HN(SO2C4F9)2/MCM-41 under the optimized reaction conditions and the heterogeneous catalyst could be recycled at least 6 times without substantial loss of activity.  相似文献   

18.
Wu TR  Shen L  Chong JM 《Organic letters》2004,6(16):2701-2704
Allylboronates derived from 3,3'-disubstituted 2,2'-binaphthols react with aldehydes and ketones to give the expected allylated products with up to >99:1 er. Highest selectivities were observed for aromatic ketones. The bis(trifluoromethyl) derivative is particularly outstanding in terms of reactivity, selectivity, and robustness. [reaction: see text]  相似文献   

19.
王烁今  孙智英  聂进   《中国化学》2008,26(12):2256-2260
全氟烷基磺酰亚胺盐与季铵型离子液体(Cu(N(C4F9SO2)2)2/[N4446][NTf2] 或 In(NTf2)3/[N4446][NTf2])组成的新催化体系,可以很好的催化芳香族化合物的硝化反应。以氯苯的硝化为例,用硝酸和醋酸酐混合物为硝化试剂,在2mol%的Cu(N(C4F9SO2)2)2或In(NTf2)3催化剂催化下,室温下反应10分钟,氯苯的转化率就可分别达到87.6% 和 90.6%,反应产物的邻/对位比为4.3和4.8。并且这种催化剂与离子液体组成的催化体系很容易被回收,并可以连续使用5次以上。  相似文献   

20.
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