7283-96-7Relevant articles and documents
Low cost preparation method of high purity 5-chlorothiophene-2-formyl chloride
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Paragraph 0047-0055; 0072-0077, (2019/03/26)
The invention relates to a low cost preparation method of high purity 5-chlorothiophene-2-formyl chloride. According to the preparation method, 2-chlorothiophene and a formylation reagent carry out reactions to generate 5-chlorothiophene-2-formaldehyde, then 5-chlorothiophene-2-formaldehyde is oxidized by an oxidant to generate 5-chlorothiophene-2-formic acid, and finally 5-chlorothiophene-2-formic acid and an acyl-chlorination reagent carry out acyl-chlorination reactions to generate 5-chlorothiophene-2-formyl chloride. 5-chlorothiophene-2-formyl chloride can be used as a key intermediate inrivaroxaban preparation. The preparation method has the advantages of cheap and easily-available raw materials, simple technical route, low raw material cost, little discharge amount of wastewater, low salt content of wastewater, environmental friendliness, and high reaction selectivity. The purity of obtained 5-chlorothiophene-2-formyl chloride is high, and the industrial production of high purity rivaroxaban is promoted.
The Hydrazine–O2 Redox Couple as a Platform for Organocatalytic Oxidation: Benzo[c]cinnoline-Catalyzed Oxidation of Alkyl Halides to Aldehydes
Stone, Ilana B.,Jermaks, Janis,MacMillan, Samantha N.,Lambert, Tristan H.
supporting information, p. 12494 - 12498 (2018/09/18)
An organocatalytic oxidation platform that capitalizes on the capacity of hydrazines to undergo rapid autoxidation to diazenes is described. Commercially available benzo[c]cinnoline is shown to catalyze the oxidation of alkyl halides to aldehydes in a novel mechanistic paradigm involving nucleophilic attack, prototropic shift, and hydrolysis. The hydrolysis and reoxidation events occur readily with only adventitious oxygen and water. A survey of the scope of viable substrates is shown along with mechanistic and computational studies that give insight into this mode of catalysis.
Sodium hypochlorite pentahydrate (NaOCl·5H2O) crystals; An effective re-oxidant for TEMPO oxidation
Okada, Tomohide,Asawa, Tomotake,Sugiyama, Yukihiro,Iwai, Toshiaki,Kirihara, Masayuki,Kimura, Yoshikazu
, p. 2818 - 2827 (2016/05/19)
The novel oxidant of sodium hypochlorite pentahydrate (NaOCl·5H2O), which is now available for industrial and laboratory use has several advantageous properties. The crystalline material has 44% of NaOCl, contains minimal sodium hydroxide and sodium chloride, and the aqueous solution indicates pH 11-12. Herein, NaOCl·5H2O crystals are examined for use as an oxidant for primary and secondary alcohols, with or without nitroxyl radicals, in the presence or absence of phase-transfer catalysts. The pentahydrate crystals alone (without nitroxyl radicals) demonstrate a powerful oxidizing ability, converting secondary alcohols to the corresponding ketones. In the presence of TEMPO (2,2,6,6-tetramethylpiperidine 1-oxyl) or 1-Me-AZADO (1-methyl-2-azaadamantane N-oxy radical), sterically hindered secondary alcohols are oxidized without pH adjustment. A proposed mechanism for the oxidation is discussed.