- Preparation of a platinum nanoparticle catalyst located near photocatalyst titanium oxide and its catalytic activity to convert benzyl alcohols to the corresponding ethers
-
A novel platinum nanoparticle catalyst closely located near the surface of titanium oxide, PtNP/TiO2, has been prepared. This catalyst has both the properties of a photocatalyst and a metal nanoparticle catalyst, and acquired environmentally friendly catalytic activity, which cannot be achieved by just one of these catalysts, to afford ethers from benzyl alcohols under the wavelength of 420 nm.
- Akiyama, Toshiki,Arisawa, Mitsuiro,Harada, Kazuo,Honma, Tetsuo,Naka, Hiroshi,Saito, Susumu,Wada, Yuki
-
p. 22230 - 22237
(2021/07/02)
-
- Bis(pertrifluoromethylcatecholato)silane: Extreme Lewis Acidity Broadens the Catalytic Portfolio of Silicon
-
Given its earth abundance, silicon is ideal for constructing Lewis acids of use in catalysis or materials science. Neutral silanes were limited to moderate Lewis acidity, until halogenated catecholato ligands provoked a significant boost. However, catalytic applications of bis(perhalocatecholato)silanes were suffering from very poor solubility and unknown deactivation pathways. In this work, the novel per(trifluoromethyl)catechol, H2catCF3, and adducts of its silicon complex Si(catCF3)2 (1) are described. According to the computed fluoride ion affinity, 1 ranks among the strongest neutral Lewis acids currently accessible in the condensed phase. The improved robustness and affinity of 1 enable deoxygenations of aldehydes, ketones, amides, or phosphine oxides, and a carbonyl-olefin metathesis. All those transformations have never been catalyzed by a neutral silane. Attempts to obtain donor-free 1 attest to the extreme Lewis acidity by stabilizing adducts with even the weakest donors, such as benzophenone or hexaethyl disiloxane.
- Thorwart, Thadd?us,Roth, Daniel,Greb, Lutz
-
supporting information
p. 10422 - 10427
(2021/05/27)
-
- Method for synthesizing ether by catalyzing alcohol through trimethyl halosilane
-
The invention discloses a method for synthesizing ether by catalyzing alcohol through trimethyl halosilane. According to the method, under the conditions of air or nitrogen atmosphere, no solvent andno transition metal catalyst, an alcohol compound is directly used as a raw material, trimethyl halosilane is used as a catalyst, and symmetric or asymmetric ether is synthesized through one-step selective dehydration reaction. According to the method, the use of strong acid, strong base and organic primary halides with high toxicity, instability and higher price is avoided, the synthesis steps are shortened, the synthesis efficiency is improved, the reaction has good selectivity, and a target ether product can be obtained preferentially.
- -
-
Paragraph 0039-0042
(2020/12/29)
-
- Breaking C-O Bonds with Uranium: Uranyl Complexes as Selective Catalysts in the Hydrosilylation of Aldehydes
-
We report herein the possibility to perform the hydrosilylation of carbonyls using actinide complexes as catalysts. While complexes of the uranyl ion [UO2]2+ have been poorly considered in catalysis, we show the potentialities of the Lewis acid [UO2(OTf)2] (1) in the catalytic hydrosilylation of a series of aldehydes. [UO2(OTf)2] proved to be a very active catalyst affording distinct reduction products depending on the nature of the reductant. With Et3SiH, a number of aliphatic and aromatic aldehydes are reduced into symmetric ethers, while iPr3SiH yielded silylated alcohols. Studies of the reaction mechanism led to the isolation of aldehyde/uranyl complexes, [UO2(OTf)2(4-Me2N-PhCHO)3], [UO2(μ-κ2-OTf)2(PhCHO)]n, and [UO2(μ-κ2-OTf)(κ1-OTf)(PhCHO)2]2, which have been fully characterized by NMR, IR, and single-crystal X-ray diffraction.
- Monsigny, Louis,Thuéry, Pierre,Berthet, Jean-Claude,Cantat, Thibault
-
p. 9025 - 9033
(2019/10/02)
-
- Aryl Boronic Acid Catalysed Dehydrative Substitution of Benzylic Alcohols for C?O Bond Formation
-
A combination of pentafluorophenylboronic acid and oxalic acid catalyses the dehydrative substitution of benzylic alcohols with a second alcohol to form new C?O bonds. This method has been applied to the intermolecular substitution of benzylic alcohols to form symmetrical ethers, intramolecular cyclisations of diols to form aryl-substituted tetrahydrofuran and tetrahydropyran derivatives, and intermolecular crossed-etherification reactions between two different alcohols. Mechanistic control experiments have identified a potential catalytic intermediate formed between the aryl boronic acid and oxalic acid.
- Estopi?á-Durán, Susana,Donnelly, Liam J.,Mclean, Euan B.,Hockin, Bryony M.,Slawin, Alexandra M. Z.,Taylor, James E.
-
supporting information
p. 3950 - 3956
(2019/02/16)
-
- Nickel Catalyzed Intermolecular Carbonyl Addition of Aryl Halide
-
In this study, we develop a nickel-catalyzed carbonyl arylation reaction employing aldehydes with aryl and allyl halides. Various aryl, α,β-unsaturated aldehyde and aliphatic aldehydes can be converted into their corresponding secondary alcohols in moderate-to-high yields. In addition, we extended this approach to develop an asymmetric reductive coupling reaction that combines nickel salts with chiral bisoxazoline ligands to give secondary alcohols with moderate enantioselectivity.
- Ishida, Seima,Suzuki, Hiroyuki,Uchida, Seiichiro,Yamaguchi, Eiji,Itoh, Akichika
-
supporting information
p. 7483 - 7487
(2019/12/11)
-
- Silver/NBS-Catalyzed Synthesis of α-Alkylated Aryl Ketones from Internal Alkynes and Benzyl Alcohols via Ether Intermediates
-
The silver hexafluoroantimonate/N-bromosuccinimide (NBS)-catalyzed synthesis of α-alkylated aryl ketones with a tertiary carbon center from internal alkynes and benzyl alcohols is reported. This reaction proceeds via the etherification of benzyl alcohols with an in situ generated benzyl bromide, formed by the reaction of benzyl alcohol with a catalytic amount of NBS and AgSbF6. Ag-catalyzed C-O cleavage of the ether leads to a tolyl radical, which undergoes addition to the alkyne, ultimately leading to the α-alkylated aryl ketone products.
- Chun, Supill,Chung, Young Keun
-
supporting information
p. 5583 - 5586
(2018/09/21)
-
- Reductive Etherification via Anion-Binding Catalysis
-
Reductive condensations of alcohols with aldehydes/ketones to generate ethers are catalyzed by a readily accessible thiourea organocatalyst that operates in combination with HCl. 1,1,3,3-tetramethyldisiloxane serves as a convenient reducing reagent. This strategy is applicable to challenging substrate combinations and exhibits functional group tolerance. Competing reductive homocoupling of the carbonyl component is suppressed.
- Zhao, Chenfei,Sojdak, Christopher A.,Myint, Wazo,Seidel, Daniel
-
supporting information
p. 10224 - 10227
(2017/08/10)
-
- Triazolylidene Iridium Complexes for Highly Efficient and Versatile Transfer Hydrogenation of C=O, C=N, and C=C Bonds and for Acceptorless Alcohol Oxidation
-
A set of iridium(I) and iridium(III) complexes is reported with triazolylidene ligands that contain pendant benzoxazole, thiazole, and methyl ether groups as potentially chelating donor sites. The bonding mode of these groups was identified by NMR spectroscopy and X-ray structure analysis. The complexes were evaluated as catalyst precursors in transfer hydrogenation and in acceptorless alcohol oxidation. High-valent iridium(III) complexes were identified as the most active precursors for the oxidative alcohol dehydrogenation, while a low-valent iridium(I) complex with a methyl ether functionality was most active in reductive transfer hydrogenation. This catalyst precursor is highly versatile and efficiently hydrogenates ketones, aldehydes, imines, allylic alcohols, and most notably also unpolarized olefins, a notoriously difficult substrate for transfer hydrogenation. Turnover frequencies up to 260 h-1 were recorded for olefin hydrogenation, whereas hydrogen transfer to ketones and aldehydes reached maximum turnover frequencies greater than 2000 h-1. Mechanistic investigations using a combination of isotope labeling experiments, kinetic isotope effect measurements, and Hammett parameter correlations indicate that the turnover-limiting step is hydride transfer from the metal to the substrate in transfer hydrogenation, while in alcohol dehydrogenation, the limiting step is substrate coordination to the metal center.
- Mazloomi, Zahra,Pretorius, René,Pàmies, Oscar,Albrecht, Martin,Diéguez, Montserrat
-
p. 11282 - 11298
(2017/09/25)
-
- Efficient carbon-supported heterogeneous molybdenum-dioxo catalyst for chemoselective reductive carbonyl coupling
-
Reductive coupling of various carbonyl compounds to the corresponding symmetric ethers with dimethylphenylsilane is reported using a carbon-supported dioxo-molybdenum catalyst. The catalyst is air- and moisture-stable and can be easily separated from the reaction mixture for recycling. In addition, the catalyst is chemoselective, thus enabling the synthesis of functionalized ethers without requiring sacrificial ligands or protecting groups.
- Liu, Shengsi,Li, Jiaqi,Jurca, Titel,Stair, Peter C.,Lohr, Tracy L.,Marks, Tobin J.
-
p. 2165 - 2169
(2017/07/22)
-
- Ni(ii)-N′NN′ pincer complexes catalyzed dehydrogenation of primary alcohols to carboxylic acids and H2 accompanied by alcohol etherification
-
Acceptorless dehydrogenation of alcohols to carboxylic acid derivatives catalyzed by a transition metal complex is an important reaction in modern organic synthesis and catalysis, for which nickel complexes have rarely been developed. Herein we report three Ni(ii) complexes bearing pyridine-based N′NN′ type pincer ligands, which catalyze the acceptorless dehydrogenation of primary alcohols to carboxylic acids under anhyrous conditions. The complex [NiCl2(L3)] 3 (L3 = 2,6-bis(diethylaminomethyl)pyridine) displays the best catalytic reactivity, catalyzing the primary alcohols to carboxylic acids and H2 in good yields (40-90%). Further investigation reveals that an unexpected alcohol etherification occurs, which gives the second oxygen atom for the formation of the carboxylic acid. Our results give a thread for the design of new nickel complexes without phosphine and N-heterocycle carbene ligands for the acceptorless oxidation of alcohols.
- Luo, Qi,Dai, Zengjin,Luo, Qin,Jiang, Huan,Li, Hua,Zhang, Jing,Peng, Tianyou
-
p. 2506 - 2511
(2017/07/22)
-
- 4,4 the-dimethyl [...] process for the preparation of dibenzyl ether
-
The invention discloses a method for preparing 4, 4'-dimethyl dibenzyl ether. The method comprises the following steps: 1) adding p-methyl benzyl chloride, an alkali solution and a phase transfer catalyst in a reaction vessel, and full reacting at 106-122
- -
-
Paragraph 0022; 0023; 0024; 0025; 0026-0057
(2019/02/02)
-
- Selective synthesis of thioethers in the presence of a transition-metal-free solid Lewis acid
-
The synthesis of thioethers starting from alcohols and thiols in the presence of amorphous solid acid catalysts is reported. A silica alumina catalyst with a very low content in alumina gave excellent results in terms of both activity and selectivity also under solvent-free conditions. The reaction rate follows the electron density of the carbinol atom in the substrate alcohol and yields up to 99% and can be obtained for a wide range of substrates under mild reaction conditions.
- Santoro, Federica,Mariani, Matteo,Zaccheria, Federica,Psaro, Rinaldo,Ravasio, Nicoletta
-
supporting information
p. 2627 - 2635
(2017/01/09)
-
- Lewis acid-driven reaction pathways in synergistic cooperative catalysis over gold/palladium bimetallic nanoparticles for hydrogen autotransfer reaction between amide and alcohol
-
Metal nanoparticle catalysts, especially gold and its bimetallic nanoparticle catalysts, have been widely used in organic transformations as powerful and green catalysts. The concept of employing two distinct catalysts in one reaction system, such as in cooperative and synergistic catalysis, is a powerful strategy in homogeneous catalysis. However, the adaption of such a strategy to metal nanoparticle catalysis is still under development. Recently, we have found that cooperative catalytic systems of gold/palladium bimetallic nanoparticles and Lewis acid can be used for the N-alkylation of primary amides through hydrogen autotransfer reaction between amide and alcohol. Herein, the results of a detailed investigation into the effects of Lewis acids on this hydrogen autotransfer reaction are reported. It was found that the choice of Lewis acid affected not only the reaction pathway leading to the desired product, but also other reaction pathways that produced several intermediates and by-products. Weak Lewis acids, such as alkaline-earth metal triflates, were found to be optimal for the desired N-alkylation of amides.
- Miyamura, Hiroyuki,Isshiki, Satoshi,Min, Hyemin,Kobayashi, Shū
-
p. 1662 - 1668
(2016/11/09)
-
- Direct halogenation of alcohols with halosilanes under catalyst- and organic solvent-free reaction conditions
-
A chemoselective method for the direct halogenation of different types of alcohols with halosilanes under catalyst- and solvent-free reaction conditions (SFRC) is reported. Various primary, secondary and tertiary benzyl alcohols and tertiary alkyl alcohols were directly transformed to the corresponding benzyl and alkyl halides, respectively, using chlorotrimethylsilane (TMSCl) and bromotrimethylsilane (TMSBr).
- Ajvazi, Njomza,Stavber, Stojan
-
supporting information
p. 2430 - 2433
(2016/05/19)
-
- Antimony(v) cations for the selective catalytic transformation of aldehydes into symmetric ethers, α,β-unsaturated aldehydes, and 1,3,5-trioxanes
-
1-Diphenylphosphinonaphthyl-8-triphenylstibonium triflate ([2][OTf]) was prepared in excellent yield by treating 1-lithio-8-diphenylphosphinonaphthalene with dibromotriphenylstiborane followed by halide abstraction with AgOTf. This antimony(v) cation was found to be stable toward oxygen and water, and exhibited exceptional Lewis acidity. The Lewis acidity of [2][OTf] was exploited in the catalytic reductive coupling of a variety of aldehydes into symmetric ethers of type L in good to excellent yields under mild conditions using Et3SiH as the reductant. Additionally, [2][OTf] was found to selectively catalyze the Aldol condensation reaction to afford α-β unsaturated aldehydes (M) when aldehydes with 2 α-hydrogen atoms were used. Finally, [2][OTf] catalyzed the cyclotrimerization of aliphatic and aromatic aldehydes to afford the industrially-useful 1,3,5 trioxanes (N) in good yields, and with great selectivity. This phosphine-stibonium motif represents one of the first catalytic systems of its kind that is able to catalyze these reactions with aldehydes in a controlled, efficient manner. The mechanism of these processes has been explored both experimentally and theoretically. In all cases the Lewis acidic nature of the antimony(v) cation was found to promote these reactions.
- Arias Ugarte, Renzo,Devarajan, Deepa,Mushinski, Ryan M.,Hudnall, Todd W.
-
supporting information
p. 11150 - 11161
(2016/07/20)
-
- Synergistic cascade catalysis by metal nanoparticles and Lewis acids in hydrogen autotransfer
-
Of the many types of catalysis involving two or more catalysts, synergistic catalysis is of great interest because novel reactions or reaction pathways may be discovered when there is synergy between the catalysts. Herein, we describe a synergistic cascade catalysis, in which immobilized Au/Pd bimetallic nanoparticles and Lewis acids work in tandem to achieve the N-alkylation of primary amides to secondary amides with alcohols via hydrogen autotransfer. When Au/Pd nanoparticles were used with metal triflates, a significant rate acceleration was observed, and the desired secondary amides were obtained in excellent yields. The metal triflate is thought to not only facilitate the addition of primary amides to aldehydes generated in situ, but also enhance the returning of hydrogen from nanoparticles to hydrogen-accepting intermediates. This resulted in a more rapid turnover of the nanoparticle catalyst, and ultimately translated into an increase in the overall rate of the reaction. The two catalysts in this co-catalytic system work in a synergistic and cascade fashion, resulting in an efficient hydrogen autotransfer process.
- Choo, Gerald C. Y.,Miyamura, Hiroyuki,Kobayashi, Shuˉ
-
p. 1719 - 1727
(2015/08/12)
-
- Organohalide-catalyzed dehydrative O-alkylation between alcohols: A facile etherification method for aliphatic ether synthesis
-
Organohalides are found to be effective catalysts for dehydrative O-alkylation reactions between alcohols, providing selective, practical, green, and easily scalable homo- and cross-etherification methods for the preparation of useful symmetrical and unsymmetrical aliphatic ethers from the readily available alcohols. Mechanistic studies revealed that organohalides are regenerated as reactive intermediates and recycled to catalyze the reactions.
- Xu, Qing,Xie, Huamei,Chen, Pingliang,Yu, Lei,Chen, Jianhui,Hu, Xingen
-
supporting information
p. 2774 - 2779
(2015/05/27)
-
- Synthesis of ethers from carbonyl compounds by reductive etherification catalyzed by iron(III) and silyl chloride
-
A simple iron- and silyl chloride catalyzed method for the preparation of symmetrical and nonsymmetrical ethers is presented. Various aldehydes and ketones were reductively etherified by using triethylsilane as a reducing agent in the presence of 2 mol% of iron(III) oxo acetate and 8 mol% of chloro(trimethyl)silane. The reactions can be carried out at ambient temperatures and pressures with ethyl acetate as the solvent.
- Savela, Risto,Leino, Reko
-
p. 1749 - 1760
(2015/06/16)
-
- Reductive coupling reaction of aldehydes using indium(III) triflate as the catalyst
-
A reductive coupling reaction was effectively developed to convert an aldehyde to its symmetrical ether. The successful reactions required Et 3SiH and CH2Cl2 as the suitable solvent in the presence of a catalytic amount of In(OTf)3. Various aldehydes were subjected to the method, and each afforded the expected ethers in good to excellent yields.
- Mineno, Tomoko,Tsukagoshi, Rie,Iijima, Tsubasa,Watanabe, Kazuki,Miyashita, Hiroyuki,Yoshimitsu, Hitoshi
-
p. 3765 - 3767
(2014/07/07)
-
- Zinc-catalyzed reduction of aldehydes with a hydrosilane leading to symmetric ethers and silyl ethers
-
The efficient reductive etherification of aromatic or aliphatic aldehydes using a reducing system that combines Zn(OTf)2 with either TMDS or Et3SiH is described. The present reducing system can also be applied to the hydrosilylation of aromatic aldehydes having either a strong electron-withdrawing group or a pyridine ring.
- Sakai, Norio,Nonomura, Yoshifumi,Ikeda, Reiko,Konakahara, Takeo
-
p. 489 - 491
(2013/06/26)
-
- Photolytic decomposition of dibenzylic sulfites
-
The photolytic decay of a library of para-substituted dibenzylic sulfites has been evaluated by UV radiation in a Srinivasan-Griffin-Rayonet photochemical reactor in various deuterated solvents. The decay for each dibenzylic sulfite was examined with respect to Swain and Lupton's field constant, F. The rate of photolytic decay varies depending on the identity of the benzyl substituents. Furthermore, it has been observed that the solvent affects both the rate of sulfite photolytic decay as well as final product distribution.
- Grenga, Paolo N.,Stoutenburg, Eric G.,Priefer, Ronny
-
p. 4933 - 4937
(2012/11/13)
-
- Dehydration of benzyl alcohols in phosphonium ionic liquids: Synthesis of ethers and alkenes
-
The dehydration of benzylic alcohols has been studied in several phosphonium ionic liquids in the absence of any metal catalysts. Benzyl ethers and alkenes were obtained from primary and secondary benzylic alcohols in good to excellent yields for these reactions. Commercially available hydrophobic phosphonium ionic liquids containing the trihexyl(tetradecyl)phosphonium cation paired with six different anions were used for the reactions under microwave irradiation. The interaction of the substrate with the ionic liquid was investigated using different NMR techniques, such as NOESY NMR. The effects of cation and anions on the behaviour of these ionic liquids in the reactions were studied in order to understand the mechanism. A catalytic cycle is proposed involving activation of the benzyl alcohol by the phosphonium cation. Copyright
- Kalviri, Hassan A.,Kerton, Francesca M.
-
experimental part
p. 3178 - 3186
(2012/01/03)
-
- The reductive etherification of carbonyl compounds using polymethylhydrosiloxane activated by molecular iodine
-
Aldehydes and ketones undergo a smooth reductive etherification by polymethylhydrosiloxane (PMHS) in the presence of a catalytic amount of molecular iodine under mild conditions to afford the corresponding symmetrical ethers in excellent yields. This new reagent system (PMHS/I2) provides a simple and convenient route for the preparation of symmetrical ethers from carbonyl compounds.
- Yadav,Subba Reddy,Shiva Shankar,Swamy
-
experimental part
p. 46 - 48
(2010/03/24)
-
- Influence of lewis acid and solvent in the hydrosiylation of aldehydes and ketones with Et3SiH; Tris(pentafluorophenyl)borane B(C 6F5)3 versus Metal inflates [M(OTf) 3; M = Sc, Bi, Ga, and Al] - Mecha
-
The scope of the B(C6F5)3-catalyzed hydrosilylation of (X)Ph- CH=O and (X)Ph-C(R)=O was expanded to include a large set of subslitulents (X =H, p-Me, o-Me, p-F, o-F, p-Cl, p-Br, p-NO2m, m-NO2, p-Et; R
- Bach, Peter,Albright, Andrea,Laali, Kenneth K.
-
scheme or table
p. 1961 - 1966
(2009/09/06)
-
- Catalytic dehydrative etherification and chlorination of benzyl alcohols in ionic liquids
-
Dibenzyl ethers and benzyl chloride can be obtained in moderate to excellent yields through Pd-catalysed reactions in hydrophobic ionic liquids using microwave or conventional heating. The Royal Society of Chemistry 2009.
- Kalviri, Hassan A.,Petten, Chad F.,Kerton, Francesca M.
-
scheme or table
p. 5171 - 5173
(2009/12/08)
-
- Chlorine borrowing: An efficient method for an easier use of alcohols as alkylation agents
-
Chlorine functionalised tin dioxide nanoparticles proved able to partially convert alcohols into the corresponding chlorides, which act as alkylation agents with an increased electrophilicity, as evidenced on ether formation and Friedel-Crafts reactions.
- Makowski, Philippe,Rothe, Regina,Thomas, Arne,Niederberger, Markus,Goettmann, Frederic
-
scheme or table
p. 34 - 37
(2010/04/22)
-
- Perfluorinated sulfonic acid resin (Nafion-H) catalysed Ritter reaction of benzyl alcohols
-
Perfluorinated sulfonic acid resin (Nafion-H) catalyst found to be effective in promoting the Ritter reaction of benzyl alcohols with nitriles such as acetonitrile, acrylonitrile and benzonitrile to give the corresponding N-benzylamides.
- Yamato, Takehiko,Hu, Jian-Yong,Shinoda, Naoki
-
p. 641 - 643
(2008/09/17)
-
- Lanthanide(III) triflate-catalyzed thermal- and microwave-assisted synthesis of benzyl ethers from benzyl alcohols
-
The lanthanide(III) trifluoromethanesulfonate-catalyzed condensation of benzyl alcohols with primary and secondary alcohols is described. This reaction proceeds readily with benzyl alcohols that have an alkyl or aryl substituent at the α-, ortho-, or para-position using microwave radiation or heating. The intra-molecular variant of this reaction leads to cyclic benzofurans.
- Handlon, Anthony L.,Guo, Yu
-
p. 111 - 114
(2007/10/03)
-
- Organic reactions catalyzed by methylrhenium trioxide: Dehydration, amination, and disproportionation of alcohols
-
Methylrhenium trioxide (MTO) is the first transition metal complex in trace quantity to catalyze the direct formation of ethers from alcohols. The reactions are independent of the solvents used: benzene, toluene, dichloromethane, chloroform, acetone, and in the alcohols themselves. Aromatic alcohols gave better yields than aliphatic. Reactions between two different alcohols could also be used to prepare unsymmetric ethers, the best yields being obtained when one of the alcohols is aromatic. MTO also catalyzes the dehydration of alcohols to form olefins at room temperature, aromatic alcohols proceeding in better yield. When primary (secondary) amines were used as the limiting reagent, direct amination of alcohols catalyzed by MTO gave good yields of the expected secondary (tertiary) amines at room temperature. Disproportionation of alcohols to alkanes and carbonyl compounds was also observed for aromatic alcohols in the presence of MTO. On the basis of the results of this investigation and a comparison with the interaction between MTO and water, a concerted process and a mechanism involving carbocation intermediates have been suggested.
- Zhu, Zuolin,Espenson, James H.
-
p. 324 - 328
(2007/10/03)
-
- Solid Superacid-Catalyzed Organic Synthesis. 4. Perfluorinated Resinsulfonic Acid (Nafion-H) Catalyzed Friedel-Crafts Benzylation of Benzene and Substituted Benzenes
-
Nafion-H, a perfluorinated resinsulfonic acid, catalyzes Friedel-Crafts benzylation of benzene and substituted benzenes with benzyl alcohols under relatively mild experimental conditions.Reactions are clean, and water formed as a byproduct does not deactivate the catalyst.It was also found that this method is applicable to the intramolecular cycloalkylation and oligomerization of methoxybenzyl alcohols.
- Yamato, Takehiko,Hideshima, Chieko,Prakash, G. K. Surya,Olah, George A.
-
p. 2089 - 2091
(2007/10/02)
-
- Reactivities of Carbonyl Compounds in Acid-Catalyzed Hydride Transfer vs. Electron Transfer
-
Rate constants for acid-catalyzed hydride-transfer reactions from triethylsilane to a series of carbonyl compounds are compared with those for acid-catalyzed electron transfer from the excited state of 2+ to the same series of carbonyl compounds in the presence of HClO4 in acetonitrile at 298 K.
- Fukuzumi, Shunichi,Fujita, Morifumi
-
p. 2059 - 2062
(2007/10/02)
-
- Metal Complex and Phase Transfer Catalysed Nitric Oxide Reactions
-
Benzyl bromides are converted into oxime ethers by bubbling nitric oxide through a solution of the bromide in t-pentyl alcohol-3 M aqueous sodium hydroxide containing a palladium or ruthenium complex as catalyst and a quaternary ammonium salt as phase transfer agent; this provides the first example of a catalytic reaction of halides which involves free or co-ordinated nitric oxide and is also the first report of a phase transfer reaction utilizing nitric oxide as a reactant.
- Falicky, Slavomir,Alper, Howard
-
p. 1039 - 1041
(2007/10/02)
-
- Electrogenerated Acid-Assisted Preparation of Ethers from Aldehydes and Ketones
-
Symmetrical and unsymmetrical ethers are prepared from carbonyl compounds and alkoxytrimethylsilanes in the presence of hydrosilane by using an electrogenerated acid catalyst.
- Torii, Sigeru,Takagishi, Sadahito,Inokuchi, Tsutomu,Okumoto, Hiroshi
-
p. 775 - 776
(2007/10/02)
-