57625-74-8Relevant articles and documents
Nitrone Formation by Reaction of an Enolate with a Nitro Group
Shimizu, Hiroaki,Yoshinaga, Kohei,Yokoshima, Satoshi
supporting information, p. 2704 - 2709 (2021/04/12)
Ketones with a 2-nitrophenyl group at the α-position were treated with sodium hydroxide in methanol at 60 °C. Under these conditions, enolates derived from the ketones intramolecularly reacted with the nitro group to form a variety of nitrones. Additional experimental results, including the unexpected isolation of N-hydroxyindolinone as a byproduct, led to a proposed reaction mechanism, occurring via an α-hydroxyketone. The resultant nitrones underwent inter- and intramolecular 1,3-dipolar cycloaddition with olefins to afford polycyclic isoxazolidines.
Synthetic method of bilastine intermediate
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Paragraph 0011; 0026, (2021/05/12)
The invention discloses a synthetic method of a bilastine intermediate, and belongs to the technical field of organic synthesis. The method comprises the steps of (1) carrying out Friedel-Crafts reaction on benzene and alpha-methyl methacrylate in fluoroalcohol A at the temperature of -15 to 25 DEG C to obtain a compound A; (2) carrying out amine ester exchange reaction on the compound A and diisopropylamine at the temperature of 20-50 DEG C to obtain a compound B; and (3) carrying out Friedel-Crafts reaction on the compound B and ethylene oxide in fluoroalcohol B at the temperature of -15 to 25 DEG C to obtain the bilastine intermediate. According to the method, cheap benzene is taken as a raw material, and the intermediate alpha, alpha-dimethyl-4-(2-ethoxyl) phenylacetyldiisopropylamine is obtained through Friedel-Crafts alkylation, amine ester exchange and further Friedel-Crafts alkylation. In the step (2), a diisopropyl group is relatively large, so that the positioning effect is changed, and the problem of excessive isomers in the Friedel-Crafts alkylation process is avoided. The proportion of Friedel-Crafts alkylation para-position and meta-position products can be 95% or above.
Preparation method of aromatic hydrocarbon compound
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Paragraph 0062-0065, (2020/12/30)
The invention relates to a preparation method of an aromatic hydrocarbon compound, and particularly discloses a preparation method of a compound as shown in a formula I. The preparation method comprises the following step: in trifluoroacetic acid, under the action of triethylsilane, carrying out a reduction reaction as shown in the specification on a compound as shown in a formula II. The invention further discloses a preparation method of the compound 1, wherein the preparation method is simple in raw material, simple and convenient to operate, low in equipment requirement, small in environmental pollution, low in cost and very suitable for industrial production.
Direct Synthesis of Cyclopropanes from gem-Dialkyl Groups through Double C-H Activation
Clemenceau, Antonin,Thesmar, Pierre,Gicquel, Maxime,Le Flohic, Alexandre,Baudoin, Olivier
supporting information, p. 15355 - 15361 (2020/10/20)
Cyclopropanes are important structural motifs found in numerous bioactive molecules, and a number of methods are available for their synthesis. However, one of the simplest cyclopropanation reactions involving the intramolecular coupling of two C-H bonds on gem-dialkyl groups has remained an elusive transformation. We demonstrate herein that this reaction is accessible using aryl bromide or triflate precursors and the 1,4-Pd shift mechanism. The use of pivalate as the base was found to be crucial to divert the mechanistic pathway toward the cyclopropane instead of the previously obtained benzocyclobutene product. Stoichiometric mechanistic studies allowed the identification of aryl- and alkylpalladium pivalates, which are in equilibrium via a five-membered palladacycle. With pivalate, a second C(sp3)-H activation leading to the four-membered palladacycle intermediate and the cyclopropane product is favored. A catalytic reaction was developed and showed a broad scope for the generation of diverse arylcyclopropanes, including valuable bicyclo[3.1.0] systems. This method was applied to a concise synthesis of lemborexant, a recently approved anti-insomnia drug.
Harnessing Applied Potential: Selective β-Hydrocarboxylation of Substituted Olefins
Alkayal, Anas,Buckley, Benjamin R.,Malkov, Andrei V.,Montanaro, Stephanie,Tabas, Volodymyr,Wright, Iain A.
supporting information, (2020/02/13)
The construction of carboxylic acid compounds in a selective fashion from low value materials such as alkenes remains a long-standing challenge to synthetic chemists. In particular, β-addition to styrenes is underdeveloped. Herein we report a new electrosynthetic approach to the selective hydrocarboxylation of alkenes that overcomes the limitations of current transition metal and photochemical approaches. The reported method allows unprecedented direct access to carboxylic acids derived from β,β-trisubstituted alkenes, in a highly regioselective manner.
ARYL-SUBSTITUTED ACETAMIDE AND PYRROLIDIN-2-ONE DERIVATIVES AND THEIR USE FOR THE TREATMENT OF SEIZURES
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Paragraph 0055; 0057, (2019/06/09)
Aryl-substituted acetamide and pyrrolidin-2-one (γ-butyrolactam) derivatives have useful activity in the inhibition, prevention, or treatment of seizures. The derivatives may be useful in the treatment of epilepsy, including medically refractory epilepsy, and nerve agent poisoning.
HETEROCYCLIC COMPOUNDS
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Page/Page column 75; 76; 79, (2018/07/29)
The present invention relates to compounds of the general formula (1) wherein the variables are defined as given in the description and claims. The invention further relates to uses of and to, processes and intermediates related to compounds of the general formula (I), wherein Q is wherein the substituents of I, Ia and Ib are as defined in description and claims.
Nickel-catalysed direct alkylation of thiophenes via double C(sp3)-H/C(sp2)-H bond cleavage: The importance of KH2PO4
Wang, Xie,Xie, Peipei,Qiu, Renhua,Zhu, Longzhi,Liu, Ting,Li, You,Iwasaki, Takanori,Au, Chak-Tong,Xu, Xinhua,Xia, Yuanzhi,Yin, Shuang-Feng,Kambe, Nobuaki
supporting information, p. 8316 - 8319 (2017/07/26)
A Ni-catalyzed oxidative C-H/C-H cross-dehydrogenative coupling (CDC) reaction was developed for constructing various highly functionalized alkyl (aryl)-substituted thiophenes. This method employs thiophenes and aliphatic (aromatic) amides that contain an 8-aminoquinoline as a removable directing group in the presence of a silver oxidant. The approach enables the facile one-step synthesis of substituted thiophenes with high functional group compatibility via double C-H bond cleavage without affecting C-Br and C-I bonds. DFT calculations verify the importance of KH2PO4 as an additive for promoting C-H bond cleavage and support the involvement of a Ni(iii) species in the reaction.
An electrochemical method for carboxylic ester synthesis from N-alkoxyamides
Subramanian, Kripa,Yedage, Subhash L.,Bhanage, Bhalchandra M.
, p. 10025 - 10032 (2018/05/31)
An electrochemical method for the synthesis of carboxylic as well as hindered esters from N-alkoxyamides has been reported. The electrochemical reaction proceeds through constant current electrolysis (CCE) by taking advantage of the dual role of n-Bu4NI (TBAI) as the redox catalyst as well as the supporting electrolyte. Besides providing mild reaction conditions, the present protocol is free from external oxidants and conducting salts, thereby generating nitrogen as the nonhazardous side product. Additionally, the developed procedure is highly advantageous due to its short reaction time, wide substrate scope, and gram-scale synthesis.
Continuous in situ electrogenaration of a 2-pyrrolidone anion in a microreactor: application to highly efficient monoalkylation of methyl phenylacetate
Matsumura, Yoshimasa,Kakizaki, Yoshinobu,Tateno, Hiroyuki,Kashiwagi, Tsuneo,Yamaji, Yoshiyuki,Atobe, Mahito
, p. 96851 - 96854 (2015/11/24)
We have successfully demonstrated effective generation of an electrogenerated base (EGB) such as the 2-pyrrolidone anion and its rapid use for the following alkylation reaction in a flow microreactor system without the need for severe reaction conditions. The key feature of the method is effective and selective preparation of monoalkylated products.
