88701-59-1Relevant academic research and scientific papers
Rhenium(I)-Catalyzed C-Methylation of Ketones, Indoles, and Arylacetonitriles Using Methanol
Shee, Sujan,Kundu, Sabuj
, p. 6943 - 6951 (2021/05/29)
A ReCl(CO)5/MeC(CH2PPh2)3 (L2) system was developed for the C-methylation reactions utilizing methanol and base, following the borrowing hydrogen strategy. Diverse ketones, indoles, and arylacetonitriles underwent mono-and dimethylation selectively up to 99% yield. Remarkably, tandem multiple methylations were also achieved by employing this catalytic system.
Sustainable Alkylation of Nitriles with Alcohols by Manganese Catalysis
Borghs, Jannik C.,Tran, Mai Anh,Sklyaruk, Jan,Rueping, Magnus,El-Sepelgy, Osama
, p. 7927 - 7935 (2019/06/24)
A general and chemoselective catalytic alkylation of nitriles using a homogeneous nonprecious manganese catalyst is presented. This alkylation reaction uses naturally abundant alcohols and readily available nitriles as coupling partners. The reaction tolerates a wide range of functional groups and heterocyclic moieties, efficiently providing useful cyanoalkylated products with water as the only side product. Importantly, methanol can be used as a C1 source and the chemoselective C-methylation of nitriles is achieved. The mechanistic investigations support the multiple role of the metal-ligand manganese catalyst, the dehydrogenative activation of the alcohol, α-C-H activation of the nitrile, and hydrogenation of the in-situ-formed unsaturated intermediate.
Nickel-Catalyzed Cyanation of Benzylic and Allylic Pivalate Esters
Michel, Nicholas W. M.,Jeanneret, Alexandria D. M.,Kim, Hyehwang,Rousseaux, Sophie A. L.
, p. 11860 - 11872 (2018/10/02)
A nickel-catalyzed cyanation reaction of benzylic and allylic pivalate esters is reported using an air-stable Ni(II) precatalyst and substoichiometric quantities of Zn(CN)2. Alkene additives were found to inhibit catalysis, suggesting that avoiding β-hydride elimination side reactions is essential for productive catalysis. An enantioenriched allylic ester undergoes enantiospecific cross-coupling to produce an enantioenriched allylic nitrile. This method was applied to an efficient synthesis of (±)-naproxen from commercially available starting materials.
Preparation method for tiaprofenic acid
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, (2018/04/02)
The invention relates to a preparation method for tiaprofenic acid. The method comprises the following steps: by taking 2-thiophenecarboxaldehyde as an initial raw material, reacting with methyl magnesium bromide, thereby compounding 1-(2-thienyl) alcohol; reacting with thionyl chloride for substituting chlorine group, cyaniding and hydrolyzing; and finally, performing Friedel-Crafts acylation reaction on the acquired product and benzoyl chloride, thereby acquiring tiaprofenic acid. The preparation method for tiaprofenic acid has the advantages that the common, low-cost and safe raw materialsare adopted for replacing rare, precious and dangerous raw materials, so that the serious pollution problem is avoided and the production cost is greatly lowered, besides, the process route adopted bythe invention is simple, the reaction period is short, the reaction condition is stable, the yield is high and reaches up to 90% or above, the purity of the acquired product after the reaction is high and the purity can reach up to 99% or above, so that the preparation method is suitable for industrial production.
Preparation method of non-steroidal anti-inflammatory drug tiaprofenic acid
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, (2018/03/26)
The invention relates to a preparation method of non-steroidal anti-inflammatory drug tiaprofenic acid. The preparation method includes: taking 2-chloromethyl thiophene as a starting raw material; synthesizing thiophene-2-acetonitrile by allowing 2-chloromethyl thiophene to react with trimethylsilyl cyanide; allowing thiophene-2-acetonitrile to react with dimethyl carbonate for methylation prior to cyan-hydrolysis; finally, performing benzoyl chloroformylation reaction to obtain tiaprofenic acid. The preparation method has the advantages that rare, valuable and dangerous materials are replacedwith common, cheap and safe raw materials, serious pollution problems are avoided, and production cost is greatly reduced; in addition, the process adopted in the method is short in route, short in reaction period, stable in reaction condition and high in yield which can be up to 90%, the product obtained is high in purity which can reach above 99%, and the preparation method is applicable to industrial production.
Synthetic process of tiaprofenic acid
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Paragraph 0048; 0049, (2018/04/01)
The invention relates to a synthetic process of tiaprofenic acid. The synthetic process comprises the following steps: adopting 2-thiotolene as a starting raw material, enabling 2-thiotolene to reactwith trimethylsilyl cyanide to synthesize 2-thiopheneacetonitrile by virtue of bromation, then enabling the 2-thiopheneacetonitrile to react with dimethyl carbonate to be methylated, hydrolyzing cyanogroups, and finally performing F-K reaction with benzoyl chloride, and preparing tiaprofenic acid. The synthetic process has the advantages that the conventional safe raw materials low in price are used for substituting the rare expensive and dangerous raw materials, so that the severe pollution problem is avoided, and the production cost is greatly decreased; and in addition, the process route adopted by the invention is simple, the reaction period is short, the reaction condition is stable, the yield is high and can reach more than 90 percent, the produce obtained after the reaction is highin purity, and the purity can reach more than 99 percent, so that the synthetic process is suitable for the industrialized production.
Synthetic process for non-steroidal anti-inflammatory drug tiaprofenic acid
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, (2018/01/11)
The invention relates to a synthetic process for a non-steroidal anti-inflammatory drug tiaprofenic acid. The synthetic process comprises the following steps: with thiophene as a starting material, subjecting thiophene to a reaction so as to prepare 2-(1-chloroethyl)thiophene; then reacting 2-(1-chloroethyl)thiophene with trimethylsilyl cyanide for cyanidation and hydrolysis of cyano groups; and finally carrying out a Friedel-Crafts reaction with benzoyl chloride so as to prepare tiaprofenac acid. The synthetic process has the following advantages that ordinary, cheap and safe raw materials are used for replacing rare, expensive and dangerous raw materials, so the problem of serious pollution is avoided, and production cost is greatly reduced; and the synthetic process is simple in process route, short in reaction period, stable in reaction conditions and high in yield, wherein the yield is up to 90% or more, tiaprofenic acid obtained after the reactions has a high purity of up to 99% or more, so the synthetic process is suitable for industrial production.
Cyanide-Free and Broadly Applicable Enantioselective Synthetic Platform for Chiral Nitriles through a Biocatalytic Approach
Betke, Tobias,Rommelmann, Philipp,Oike, Keiko,Asano, Yasuhisa,Gr?ger, Harald
, p. 12361 - 12366 (2017/09/06)
A cyanide-free platform technology for the synthesis of chiral nitriles by biocatalytic enantioselective dehydration of a wide range of aldoximes is reported. The nitriles were obtained with high enantiomeric excess of >90 % ee (and up to 99 % ee) in many cases, and a “privileged substrate structure” with respect to high enantioselectivity was identified. Furthermore, a surprising phenomenon was observed for the enantiospecificity that is usually not observed in enzyme catalysis. Depending on whether the E or Z isomer of the racemic aldoxime substrate was employed, one or the other enantiomer of the corresponding nitrile was formed preferentially with the same enzyme.
Catalytic asymmetric protonation of silyl ketene imines
Guin, Joyram,Varseev, Georgy,List, Benjamin
supporting information, p. 2100 - 2103 (2013/03/28)
An efficient catalytic and highly enantioselective protonation of silyl ketene imines is described. The reaction is catalyzed by the chiral phosphoric acids TRIP or STRIP in the presence of a stoichiometric amount of methanol as the proton source and silyl acceptor. A variety of substituted racemic silyl ketene imines have been transformed into highly enantioenriched nitriles.
