23982-79-8Relevant academic research and scientific papers
Preparation method of benzimidazole compounds in sterilizing agent and pesticide
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Paragraph 0050-0052; 0064-0068; 0099-0100, (2021/03/03)
The invention provides a new synthesis method of benzimidazole compounds which can be applied to preparation of disinfectants and pesticides, and the benzimidazole compounds are synthesized by using oxalyl diamine compounds which are simple and easy to prepare as ligands and using CuI to catalyze o-amide substituted chlorinated aryl compounds. The method has the advantages that a reaction system is cheap and easy to prepare, the method can be suitable for industrial production, and reaction conditions are mild. In addition, the reaction also has the advantages of low catalyst and ligand equivalents, simplicity, convenience, economy, wide substrate application range and the like. The benzimidazole compound obtained by the preparation method can be used as a killing agent and a pesticide bactericide.
One-pot strategy of copper-catalyzed synthesis of 1,2-disubstituted benzimidazoles
Xie, Caixia,Han, Xushuang,Gong, Jian,Li, Danyang,Ma, Chen
, p. 5811 - 5819 (2017/07/22)
A simple, one-pot and copper-catalyzed coupling reaction for the construction of 1,2-disubstituted benzimidazole derivatives is described. A low-cost copper salt and a weak base K3PO4 were utilized in this reaction. A variety of 1,2-disubstituted benzimidazoles were obtained in moderate to excellent yields.
Building heterocyclic systems with RC(OR)2+ carbocations in recyclable bronsted acidic ionic liquids: Facile synthesis of 1-substituted 1H-1,2,3,4-tetrazoles, benzazoles and other ring systems with CH(OEt)3 and EtC(OEt)3 in [EtNH 3][NO3] and [PMIM(SO3H)][OTf]
Aridoss, Gopalakrishnan,Laali, Kenneth K.
experimental part, p. 2827 - 2835 (2011/06/23)
1-Aryl/alkyl-1H-1,2,3,4-tetrazoles can conveniently be synthesized in one-pot reactions from the corresponding amines by reaction with TMSN 3 and CH(OEt)3 using the readily available, recyclable, Bronsted acidic ionic liquids [EtNH3][NO3] IL-1 and [PMIM(SO3H)][OTf] IL-2 under mild conditions in high yields. Based on comparative reactions, whereas both ILs are excellent promoters, reactions are completed with shorter reaction times and in higher yields with IL-2. Among 24 examples provided, identical products were obtained via the two ILs, except in the case of 2-aminobenzoic acid where tetrazole was formed with IL-2 and 2-ethylquinazolin-4(3H)-one was formed with IL-1. By leaving out TMS-N 3 from the reaction, the in-situ formed CH(OEt)2 + and EtC(OEt)2+ (via their corresponding orthoesters) react under sonication with o-phenylenediamine bearing various substituents, o-aminothiophenol and o-aminophenol to form a wide array of benzazoles (benzimidazole, benzothiazole and benzoxazole) and quinazolin-4(3H)-one in high yields (18 examples). The two ILs reacted differently in reaction with 2-aminobenzamide, whereas quinazolin-4(3H)one was formed with IL-2/CH(OEt)3, the "unexpected" N-ethylquinazolin-4(3H)one was isolated with IL-1/CH(OEt)3. The latter was also formed from 2-aminobenzoic acid in IL-1/CH(OEt)3. Mechanistic implications are addressed. The reported protocols enable rapid assembly of a host of heterocyclic systems in high yields with the added advantage of recycling and re-use of the ILs.
