Long-Chained Acidic Ionic Liquids-Catalyzed Cyclization of 2-Substituted Aminoaromatics with β-Diketones: A Metal-Free Strategy to Construct Benzoazoles was written by Miao, Chengxia;Hou, Qin;Wen, Yating;Han, Feng;Li, Zhen;Yang, Lei;Xia, Chun-Gu. And the article was included in ACS Sustainable Chemistry & Engineering in 2019.HPLC of Formula: 5676-58-4 This article mentions the following:
With long-chained acidic ionic liquids as catalysts, a metal-free, efficient, and universal strategy was developed to synthesize a series of benzoazole compounds through intermol. cyclization of 2-aminophenols/thiophenols/anilines with β-diketones. Compared with traditional ionic liquids, the long-chained ionic liquids with certain surfactivity exhibited better catalytic activities perhaps for micellar action and could be reused at least six times. A mechanism that involves condensation, nucleophilic addition, and C-C bond cleavage was proposed, and the imine compound was recognized as an important intermediate in the reaction. In the experiment, the researchers used many compounds, for example, 2,5-Dimethylbenzoxazole (cas: 5676-58-4HPLC of Formula: 5676-58-4).
2,5-Dimethylbenzoxazole (cas: 5676-58-4) belongs to benzoxazole derivatives. Its aromaticity makes it relatively stable, although as a heterocycle, it has reactive sites which allow for functionalization. A number of marketed drugs are available having benzoxazole as core active moiety like, nonsteroidal anti-inflammatory drug (NSAID)—flunoxaprofen, benoxaprofen, antibiotic—calcimycin.HPLC of Formula: 5676-58-4
Referemce:
Benzoxazole – Wikipedia,
Benzoxazole | C7H5NO – PubChem