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1.
α-Alkylation of ketones with styrene derivatives was developed using a mesitylcopper-dppp complex as a soft Brønsted base catalyst. No waste derived from the alkylating reagent was produced in this catalytic alkylation reaction. The bisphosphine ligand structure, as well as the reaction solvent, had profound effects on catalyst activity. The reaction proceeded under mild conditions from a range of ketones and styrene derivatives. The present catalysis is especially useful for the selective mono-alkylation of ketones. 相似文献
2.
Palladium immobilized on an amide and ether functionalized porous organic polymer (Pd@AEPOP) is reported to be an effective heterogeneous catalyst for the Heck cross-coupling reaction of aryl iodides with styrene for the synthesis of diphenylethene derivatives. Excellent yields can be obtained using a 0.8 mol% Pd catalyst loading under the optimized reaction condition. The heterogeneous Pd@AEPOP catalyst can also be applied on the Suzuki reaction and the reduction of nitroarene. 相似文献
3.
Syoaki Ide Hidesaburo Nanbu Takeshi Kuroki Tadashi Ikemura 《Journal of Analytical and Applied Pyrolysis》1984,6(1):69-80
To obtain useful products from polystyrene degradation waste, the catalytic degradation of polystyrene over an active charcoal catalyst was carried out. By controlling the reaction conditions, the selective recovery of styrene dimer derivatives, a promising sourse of useful industrial additives, was investigated. Cis- and trans-l,3-diphenyl-2-butene. 1,3-diphenyl-1-butene and 1,3-diphenylbutane were detected as the main products. The yield of styrene dimer derivatives was about 15 wt.% of the total liquid products recovered. Also. selective recovery of the styrene dimer derivatives by the catalytic reaction of polystyrene in the presence of a catalyst was possible by controlling the contact time and activity of the catalyst. 相似文献
4.
5.
The copper-catalysed aziridination of styrene derivatives using either Cu(OTf)2 as a homogeneous catalyst or copper-exchanged zeolite Y modified as a heterogeneous catalyst with bis(oxazoline) using [N-(p-nitrophenylsulfonyl)imino]phenyliodinane (PhI=NNs) as nitrene donor is described and discussed. For the homogeneously catalysed reaction virtually all the substituted derivatives gave lower yields of the aziridine with lower ee when compared with styrene, although 4-chlorostyrene did give enhanced ee. For the heterogeneous catalysed reaction the styrene derivatives often gave enhanced yield, particularly when the substituent was in the 4-position. Particularly high ee was observed for 2-chlorostyrene (95%) and 4-chlorostyrene (94%) and in general the ee observed for the heterogeneously catalysed reaction with the 2- and 4-substituted derivates was significantly higher than that for the equivalent homogeneously catalysed reaction. With copper-exchanged zeolite Y the leaching of Cu2+ into solution during reaction was much lower for the substituted styrene derivatives (0.4-7% of total Cu) than with styrene itself (10.3% of the total Cu). The effect of reaction time on aziridine yield reveals an S-shaped profile that is accentuated by the position of the substituent and this effect is observed for both the homogeneously catalysed pathway and the heterogeneously catalysed reaction. A series of competitive experiments in which styrene was co-reacted with equivalent quantities of 2-, 3- and 4-chlorostyrene revealed that the reaction of styrene enhanced by the other substrate, but the rate of reaction of the substituted styrene was decreased. Co-reaction of 2- and 4-chlorostyrene reveals interesting competitive effects, which are discussed in terms of the nature of the active site. 相似文献
6.
Walysson Ferreira de Paiva Ingredy Bastos Braga João Vitor de Assis Sandra Milena Bonilla Castañeda Ángel Gabriel Sathicq Valeria Palermo Gustavo Pablo Romanelli Ricardo Natalino Marcio José da Silva Felipe Terra Martins Gustavo Senra Gonçalves de Carvalho Giovanni Wilson Amarante Sergio Antonio Fernandes 《Tetrahedron》2019,75(27):3740-3750
The application of immobilizing calixarene onto the surface of silica using a sol-gel method, as an efficient heterogeneous catalyst (CX4SO3HSi(n)) for multicomponent Povarov reaction has been described. Catalytic activity of the CX4SO3HSi(n) for the synthesis of julolidines under greener and environmentally benign conditions in simple and efficient method was explored. Notably, only 0.5 mol% of the catalyst is sufficient to catalyze the Povarov solvent-free reaction under microwave-assistance. Besides, this protocol allows the construction of four new C–C bonds and two C–N bonds in a single step. To the best of our knowledge, this consists the first silica support calix[4]arene as a heterogeneous catalyst for multicomponent synthesis of julolidines. 相似文献
7.
氟喹诺酮作为钯催化Heck反应有效配体的研究 总被引:1,自引:2,他引:1
研究了氟喹诺酮作为钯催化Heck反应的有效配体. 碘苯、溴苯和其它芳基卤衍生物与丙烯酸丁酯、苯乙烯等取代乙烯类化合物在钯和氟喹诺酮的催化下发生Heck反应. 讨论了配体、催化剂用量、碱和溶剂对Heck反应产率的影响. 该反应的最优化条件是: 钯源为Pd(OAc)2 (0.1 mol%), 诺氟沙星作为配体(0.2 mol%), K2CO3作为碱, DMA作为溶剂, 取代碘苯及溴苯和它们的衍生物与丙烯酸丁酯、苯乙烯等乙烯基化合物的反应均可以得到高收率的目标偶联产物. 相似文献
8.
Dharminder Sharma Sandeep Kumar Arun K. Shil Nitul Ranjan Guha Pralay Das 《Tetrahedron letters》2012,53(52):7044-7051
Solid supported palladium nano/microparticles were found to be active catalysts to perform mono- and β,β-double-Heck reactions. Different β-unsubstituted and substituted alkenes including acrylate, methacrylate, crotonate, styrene, acrylonitrile, and acrylamide were investigated successfully for mono- and β,β-double-Heck reactions with aryl iodide under milder reaction condition. One-pot β,β-double-Heck reaction of aryl iodides with α,β-unsaturated ester, amide, nitrile, and styrene derivatives were also performed under standard reaction conditions. Wide functional group tolerance, easy catalyst recovery, and recyclability up to twelve times without significant loss of catalytic activity added extra importance to the present process. 相似文献
9.
[Reaction: see text] The intermolecular enyne metathesis between alkynes and styrene derivatives was developed to study electronic effects in enyne metathesis. A Hammett plot for the overall reaction, catalyst initiation and vinyl carbene turnover was determined with the second generation Grubbs ruthenium carbene catalyst. 相似文献
10.
The C-H bond of a terminal alkyne adds to a carbon-carbon double bond of 1,3-dienes, styrenes, and norbornene at room temperature in the presence of a nickel catalyst in regio- and stereoselective manners. Reaction of triisopropylsilylacetylene with 1-substituted 1,3-butadiene derivatives afforded hydroalkynylation products via introduction of a hydrogen atom and a triisopropylsilylethynyl group to 4- and 3-positions of the dienes, respectively. Likewise, 1-triisopropylsiloxy-1,3-butadiene, 1,3-pentadiene, 1-cyclohexen-1-yl-1,3-butadiene, and 1,3-cyclohexadiene underwent the hydroalkynylation reaction, giving the corresponding 1,4-enyne derivatives in good yields at room temperature. Reaction of p-substituted styrene with triisopropylsilylacetylene also proceeded in the presence of the nickel catalyst, giving the branched hydroalkynylation products in good yields. Norbornene gave a exo-addition product in good yield under the same reaction conditions. 相似文献
11.
Yakai Feng Jingwu Sun Yinbang Zhu Weiyu Chen 《Journal of polymer science. Part A, Polymer chemistry》1997,35(7):1283-1291
A series of styrene derivatives were synthesized from aromatic substances by Friedel-Crafts acylation, reduction, and dehydration. Alternating copolymers of styrene derivatives and carbon monoxide were prepared in the presence of a palladium(II) catalyst. The characterization of the polyketones produced was performed by use of 1H-NMR, IR, WXRD, and EA methods. The thermal degradation of the regular alternating copolymer of carbon monoxide and styrene (STCO) has been studied by thermal gravimetry (TG). The TG spectra of solid samples were recorded both in nitrogen and in air. The degradation reaction order and activation energy were determined. The photodegradation of STCO was investigated. In addition, the block copolymerization of STCO with methyl methacrylate under UV irradiations was also studied. It is found that the tertiary amine can promote this photopolymerization. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1283–1291, 1997 相似文献
12.
A number of indenes have been prepared in good yields by treating o-bromobenzyl zinc bromide 1 with various terminal and internal alkynes in the presence of a nickel catalyst. The nickel-catalyzed carboannulation reaction was successfully extended to the synthesis of indane derivatives by reaction of 1 with acrylates and styrene. 相似文献
13.
A series of nickel complexes with β‐ketoamine ligands based on pyrazolone derivatives were synthesized by condensing pyrazolone with aniline, 2‐chloroaniline or naphthylamine and then reacting the produced β‐ketoamine with nickel halide. The solid‐state structures of these three complexes were determined by single‐crystal X‐ray diffraction. The bis(β‐ketoamine)nickel complexes are all air‐stable and can act as highly active catalyst precursors for styrene polymerization with activation of methylaluminoxane under mild reaction conditions. The activity of the catalyst for styrene polymerization is as high as 2.10 × 105 g polymer/mol Ni h. Both steric and electronic effects were found to be important and influential for catalytic activity. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
14.
Jónsson S Odille FG Norrby PO Wärnmark K 《Chemical communications (Cambridge, England)》2005,(4):549-551
A dynamic supramolecular system involving hydrogen bonding between a Mn(III) salen catalyst and a Zn(II) porphyrin receptor exhibits selectivity for pyridine appended cis-beta-substituted styrene derivatives over phenyl appended derivatives in a catalytic epoxidation reaction. 相似文献
15.
高分子负载型双金属催化剂苯乙烯及其衍生物的氢酯基化反应 总被引:4,自引:0,他引:4
用SiO2负载天然生物高分子材料壳聚糖(简写为CS),再与PbCl2配位,制得催化剂SiO2-CS-PdCl2,利用Pd-Ni双金属协同效应和高分载体对催化活性物种的保护,使催化剂在苯乙烯及其衍及生物的氢酯基化反应中表现出了较高的催化活性和选择性。并重点考察了反应条件、不同底物以及其它载体对反应的影响。 相似文献
16.
Syntheses of the title compounds were achieved by rearrangement of the isomeric cyclopropyl-α-ketoesters using acid treated aluminium oxide in a chromatographic column. The cyclopropyl derivatives were obtained from copper catalyzed reaction of a diazoketoester to the properly substituted styrenes. On the basis of an observed substituent effect a mechanism is proposed involving a transition state incorporating both the styrene, the diazoketoester and the catalyst. The role of the latter is most likely exerted in the initiating step of the radical reaction invoked. p-Methoxy styrene also yielded the dihydrofuran directly. 相似文献
17.
《Green Chemistry Letters and Reviews》2013,6(4):621-632
Abstract Hydroarylation of styrene and its derivatives with arenes and heteroarenes was studied using Montmorillonite K-10 as an efficient, environmentally benign, economical, greener, and recyclable catalyst. The reaction gives 1,1-diarylalkanes with a very high selectivity and excellent yields in short time with greater substrate compatibility. 相似文献
18.
Studies are described that reveal the steps of the anti-Markovnikov hydroamination of vinylarenes with alkylamines catalyzed by Ru(COD)(2-methylallyl)2, bis(diphenylphosphino)pentane, and TfOH. Treatment of the catalyst components with an excess of styrene under the catalytic reaction conditions afforded a new ruthenium eta6-styrene complex with an ancillary tridentate PCP ligand. This ruthenium complex was active as catalyst for the hydroamination of styrene with morpholine to give the anti-Markovnikov adduct as a single regioisomer in high yield. Studies of the reactivity of the eta6-styrene complex revealed two reactions that comprise a catalytic cycle for anti-Markovnikov hydroamination: nucleophilic addition of morpholine to the ruthenium eta6-styrene complex to afford a ruthenium eta6-(2-aminoethyl)benzene complex and arene exchange of the ruthenium eta6-(2-aminoethyl)benzene complex with styrene to regenerate the ruthenium eta6-styrene complex. The addition of morpholine and the exchange of arene occurred with comparable rates. These results strongly suggest that the ruthenium-catalyzed anti-Markovnikov addition of alkylamines to vinylarenes occurs by a new reaction mechanism for hydroamination involving nucleophilic attack on the eta6-vinylarene complex and exchange of the aminoalkylarene complex product with free vinylarene. This mechanism is a rare example of catalytic chemistry through pi-arene complexes. These mechanistic data were used to select derivatives of the DPPP ligand that improve the rates of the catalytic process. 相似文献
19.
Amarajothi Dhakshinamoorthy Dr. Mercedes Alvaro Dr. Hermenegildo Garcia Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(28):8530-8536
An iron‐based metal–organic framework, [Fe(BTC)] (BTC: 1,3,5‐benzenetricarboxylate) is an efficient catalyst in the ring opening of styrene oxide with alcohols and aniline under mild reaction conditions. Out of the various alcohols tested for ring opening of styrene oxide, methanol was found to be the most reactive in terms of percentage conversion and reactivity. The rate of the ring‐opening reaction of styrene oxide decreases as the size of the alcohol is increased, suggesting the location of active sites in micropores. [Fe(BTC)] was a truly heterogeneous catalyst and could be reused without loss of activity. The analogous compound [Cu3(BTC)2] was also found to be effective, although with somewhat lower activity than [Fe(BTC)]. The present heterogeneous protocol is compared with a homogeneous catalyst to give an insight into the reaction mechanism. 相似文献
20.
Sk Manirul Islam Anupam Singha Roy Paramita Mondal Manir Mobarok Brindaban Roy Noor Salam Sumantra Paul Sanchita Mondal 《Monatshefte für Chemie / Chemical Monthly》2012,36(4):815-823