5328-01-8Relevant articles and documents
A new alkylation of aryl alcohols by boron trifluoride etherate
Jumbam, Ndze Denis,Maganga, Yamkela,Masamba, Wayiza,Mbunye, Nomthandazo I.,Mgoqi, Esethu,Mtwa, Sphumusa
, (2019/10/28)
The ethylation of aryl alcohols by an ethyl moiety of boron trifluoride etherate is described. The reaction proceeded cleanly and afforded good yields of the corresponding aryl ethyl ethers. It tolerated the presence of functional groups such as aryl, alkyl, halogens, nitro, nitrile, and amino. However, the presence of amino or nitro groups ortho to a hydroxyl group of an aryl compound drastically reduced the yields of the anticipated products due to the chelation of the aforementioned functional groups with boron trifluoride etherate. A nitrogen atom in the aromatic ring system, as exemplified by hydroxypyridine and 8-hydroxyquinoline, completely inhibited the reaction. Resorcinol, hydroquinone, and aryl alcohols with aldehyde functions decomposed under the reaction conditions.
Microwave-assisted synthesis method for ethylation reaction
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Paragraph 0012, (2019/10/05)
The invention relates to a microwave-assisted synthesis method for an ethylation reaction. The method is characterized in that a reaction substrate is in an organic solvent, trifluoroacetic acid ethyl ester is taken as an ethylation reagent, in the presence of an alkali, microwave-assisted heating is carried out for 2 minutes, and a corresponding ethylation product can be obtained. The invention provides a new method for the ethylation reaction. The reaction rate of the method is several times higher than that of a traditional method, the operation is simple and convenient, the cost is low, the reaction time is short, the application range of the substrate is wide, the use of the expensive or hypertoxic ethylation reagent can also be avoided, and the method has higher application value.
Versatile functionalization of electron rich-fused heterocyclic arenes via electrophilic aromatic addition reaction and their applications
Jang, Keun Sam,Shin, Dong Seok,Srisook, Ekaruth,Song, Ho-Chun,Chi, Dae Yoon
supporting information, p. 5106 - 5114 (2016/07/25)
Divergent functionalized 8-methoxyquinaldines were synthesized via regioselective debromination, 1,3-bromine shift process, aromatization with treatment of a strong base, nucleophilic substitution reaction at the C7 position using amines and cyanide as a nucleophile in the absence of a metal source and a catalyst from an unusual electrophilic aromatic addition (AdEAr) reaction products 7 and 8. In addition, quinaldine-7,8-dione was prepared by presence of CAN (ceric ammonium nitrate) in AcOH and H2O for 10 min at room temperature from N-(alkylamino)-8-methoxyquinalidines. During the AdEAr reaction, new stereoselective dearomatized addition products were generated via discriminative reaction routes depending on the methoxy and bromine occupancy position. The AdEAr reaction not only allowed for the functionalization of electron rich-fused heterocyclic arenes, but also provided a new synthetic route to an alternative mechanism for electrophilic aromatic substitution reactions.
SNAAP sulfonimidate alkylating agent for acids, alcohols, and phenols 1
Maricich, Tom J.,Allan, Matthew J.,Kislin, Brett S.,Chen, Andrea I-T.,Meng, Fan-Chun,Bradford, Christine,Kuan, Nai-Chia,Wood, Jeremy,Aisagbonhi, Omonigho,Poste, Alethea,Wride, Dustin,Kim, Sylvia,Santos, Therese,Fimbres, Michael,Choi, Dianne,Elia, Haydi,Kaladjian, Joseph,Abou-Zahr, Ali,Mejia, Arturo
, p. 3361 - 3368 (2014/01/06)
Stable, crystalline ethyl N-tert-butyl-4-nitrobenzenesulfonimidate has been prepared in high yield by direct O-ethylation of N-tert-butyl-4- nitrobenzenesulfonamide with iodoethane and silver(I) oxide in dichloromethane. This sulfonimidate directly ethylates various acids to esters; the stronger the acid, the faster it alkylates and in higher yield. It readily ethylates alcohols and phenols to ethers at room temperature in the presence of tetrafluoroboric acid catalyst without molecular rearrangements or racemization. We have defined these reactions as SNAAP alkylations: [substitution, nucleophilic of acids, alcohols and phenols]. The hard sulfonimidate alkylating agent is chemoselective, preferring oxygen > nitrogen > sulfur. The sulfonamide byproduct of alkylation is readily recycled to the sulfonimidate. Georg Thieme Verlag Stuttgart . New York.
Microwave-Assisted solid-liquid phase alkylation of naphthols
Balint, Erika,Kovacs, Orsolya,Drahos, Laszlo,Keglevich, Gyoergy
, p. 330 - 336 (2013/07/26)
The microwave promoted alkylation of 1- and 2-naphthols with benzyl, butyl, ethyl and isopropyl halides in the presence of an alkali carbonate may result in O- and C-Alkylated products. The alkylations were O-selective in the presence of K2CO3 in acetonitrile as the solvent and in the absence of phase transfer catalyst. The alkylations utilizing butyl and ethyl halides were also O-selective in solventless accomplishment and in the presence of triethylbenzylammonium chloride.
Heterogeneous palladium-catalyzed synthesis of aromatic ethers by solvent-free dehydrogenative aromatization: Mechanism, scope, and limitations under aerobic and non-aerobic conditions
Sutter, Marc,Lafon, Romain,Raoul, Yann,Metay, Estelle,Lemaire, Marc
supporting information, p. 5902 - 5916 (2013/09/23)
Starting from cyclohexanone derivatives and alcohols, both non-aromatic precursors, aryl ethers could be synthesized in good yields and with good selectivities in the presence of a catalytic amount of Pd/C, in one step, without added solvent, in a reaction vessel open to air. For less reactive substrates, the addition of 1-octene in a closed system under non-aerobic conditions improved the conversion. In addition, the catalyst could be recycled several times with no decrease in the yield of the aryl ether. The process was also used with tetralone derivatives and polyols. Several reactions were performed to propose a mechanism for this transformation. The formation of an enol ether followed by a dehydrogenation reaction seem to be the key steps of this reaction. Aryl ethers were prepared in good yields and with good selectivities in a solvent-free and heterogeneous catalytic dehydrogenative alkylation of cyclohexanones with various alcohols. Three different complementary routes were used, and for the first time, non-aerobic, safe conditions could be used. Moreover, the catalyst could be recycled several times with no decrease in the yield of the aryl ether. Copyright
Oxidative trifluoromethylation of arylboronates with shelf-stable potassium (trifluoromethyl)trimethoxyborate
Khan, Bilal A.,Buba, Annette E.,Goossen, Lukas J.
supporting information; body text, p. 1577 - 1581 (2012/03/10)
Introducing CF3: Arylboronic acid pinacol esters are converted into the corresponding benzotrifluorides with the easy-to-use one-component trifluoromethylating reagent potassium (trifluoromethyl)trimethoxyborate, mediated by copper acetate under an oxygen atmosphere (see scheme). Copyright
Solvent-free Williamson synthesis: An efficient, simple, and convenient method for chemoselective etherification of phenols and bisphenols
Massah, Ahmad R.,Mosharafian, Masumeh,Momeni, Ahamad R.,Aliyan, Hamid,Naghash, H. Javaherian,Adibnejad, Mohamad
, p. 1807 - 1815 (2008/02/02)
Etherification of phenols with dimethyl- and diethylsulfates and benzyl chloride was performed efficiently in the presence of a suitable solid base, NaHCO3 or K2CO3, under solvent-free conditions. The reaction proceeded rapidly at low temperature, and the corresponding ethers were obtained with high purity and excellent yield. Selective etherification of electron-poor phenols in the presence of electron-rich ones and also selective mono-etherification of bisphenols are the noteworthy advantages of this method. This method is environmentally friendly. Copyright Taylor & Francis Group, LLC.
One-pot synthesis of 4-alkoxybenzo[c]thiophenes
Akbarzadeh, Tahmineh,Shafiee, Abbas
, p. 1455 - 1462 (2007/10/03)
The reaction of N-bromosuccinimide with 4,5,6,7-tetrahydrobenzo[c]thiophen-4-ones in the presence of 2,2′-azo-bis-isobutyronitrile followed by heating under reflux with different alcohols produces 4-alkoxybenzo[c]thiophenes in good yield.
Chemoselective O-methylation of phenols under non-aqueous condition
Basak, Anindita,Nayak, Mrinal K.,Chakraborti, Asit K.
, p. 4883 - 4886 (2007/10/03)
Chemoselective O-methylation of substituted phenols takes place in dry. tetrahydrofuran (THF) in the presence of LiOH.H2O and dimethylsulfate (DMS). Quantitative methyl transfer from DMS preserves the atom economy.
