725701-22-4Relevant articles and documents
Diversity in Heterocycle Synthesis Using α-Iminocarboxylic Acids: Decarboxylation Dichotomy
Hunjan, Mandeep Kaur,Laha, Joydev K.
, (2022/02/07)
Despite the structural similarity with imines, α-iminocarboxylic acids have seldom been used in heterocycles synthesis. The reactions of ortho-substituted anilines and arylglyoxylic acids in DMSO at 40 °C gave various benzo-fused five- to six-membered N-heterocycles in good to excellent yields. The reaction proceeds via intramolecular Michael addition of α-iminocarboxylic acids, generated in situ, with an ortho-substituted nucleophile, yielding an isolable unprecedented tetrahedral carboxylic acids, which upon decarboxylation without any aid of additional reagents forms the N-heterocycles. DMSO is crucial in this reaction, perhaps because of improved solubility and the ease of decarboxylation of these tetrahedral carboxylic acids. However, a copper-catalyzed reaction of ortho-substituted anilines and 2-bromoarylglyoxylic acids gave a dibenzo-fused seven-membered N-heterocycle under a basic reaction condition. Unlike intramolecular cyclization with α-iminocarboxylic acids in the first case, α-iminocarboxylic acid undergoes a competitive decarboxylation under the copper-catalyzed conditions, which upon subsequent heteroarylation form the heterocycles. Taken together, the study described herein represents two different modes of decarboxylation observed with α-iminocarboxylic acids, leading to the synthesis of divergent heterocycles and pharmaceuticals, which remained unexplored previously.
Synthesis and Antifungal Activity of Substituted 2-Aryl Benzimidazoles Derivatives
Huang, Daye,Qiu, Fang,Zhang, Zhigang,Shi, Liqiao,Cao, Chunxia,Ke, Shaoyong
, p. 2494 - 2498 (2019/08/12)
Benzimidazole fungicides were among the early systemic fungicides developed and used for controlling a wide variety of plant diseases. During the course of our screening process for active compounds, two 2-aryl benzimidazoles derivatives bearing sulfoxide group (6b and 6c) have been demonstrated to exhibit good inhibition activity against high-resistant isolate of Botrytis cinerea compared with carbendazim, and the inhibition rates are up to 46.67% and 51.11% at the concentration of 10 μg/mL, which might be considered as the active framework for the discovery of novel fungicide to high-resistant isolate of B. cinerea.
A dendritic TiO2-Co(ii) nanocomposite based on the melamine catalyzed one-pot aerobic photocatalytic synthesis of benzimidazoles
Eskandari, Ameneh,Jafarpour, Maasoumeh,Rezaeifard, Abdolreza,Salimi, Mehri
, p. 6449 - 6456 (2018/04/23)
A novel heterogeneous visible light active nanophotocatalyst was produced via modification of a nanocrystalline TiO2 surface with a cobalt(ii) complex of melamine dendrimer under ultrasonic agitation, and was characterized by different techniques such as FT-IR, XPS, EDS, ICP-AES, TGA, DRS, UV-Vis, TEM and SEM. A red-shift of the band-edge and a significant reduction of the band-gap (2.7 eV) were revealed by UV-DRS. The as-prepared dendritic nanophotocatalyst significantly promoted the aerobic synthesis of benzimidazole derivatives with biological and pharmaceutical interest by a one-pot three-step process from the photooxidation of alcohols to aldehydes followed by cyclocondensation with 1,2-phenylenediamine with good to excellent yield. This process has the potential to enable a more sustainable benzimidazole synthesis. The combination of photocatalytic and catalytic reactions presented here may help to develop a new strategy towards the development of photocatalysis-based organic synthesis.
