Synthesis of N-Aryl-2-aminobenzoxazoles from Substituted Benzoxazole-2-thiol and 2-Chloro-N-arylacetamides in KOH-DMF System
Year: 2017
Type: article
Abstract: General Information………………………………………………………………….S2General procedures for the reaction of substituted benzoxazole-2-thiol with 2-chloro-N-arylacetamides………………………………………………………..….S2Copies of 1 H, 13C NMR and HRMS spectra………………………………….……S11 S2 General Information.All starting materials and reagents were purchased from commercial suppliers.TLC was performed on 0.20 mm Silica Gel 60 F254 plates (Qingdao Ocean Chemical Factory, Shandong, China).Nuclear magnetic resonance spectra (NMR) were recorded on a Bruker spectrometer (400 MHz) with TMS as an external reference and reported in parts per million. General procedures for the reaction of substituted benzoxazole-2-thiol with 2-chloro-N-arylacetamidesTo a solution of substituted benzoxazole-2-thiol (1.0 mmol) and 2-chloro-N-arylacetamides (1.0 mmol) in DMF (10 mL) were added KOH powder (224 mg; 4 mmol) and the reacting mixture was stirred at room temperature for 5 h.After the completion of the reaction, the mixture was poured into 100 mL of water and extracted with CH2Cl2 (100 mL×3).The combined organic layers were dried over Na2SO4 and concentrated under vacuum.The residue was purified by chromatography to give the desired N-aryl-2-aminobenzoxazoles. N-(4-Chlorophenyl)benzo[d]oxazol-2-amine (3a)Yellow solid, yield 68 %, m.p. 169-172 o C, 1 H NMR (CDCl3, 400 MHz) δ: 7.13-7.17(m, 1H, 1H, 3H, Ar-H), 7.48 (d, 1H, J = 7.2 Hz, Benzoxazole-H), 7.57-7.60(m, 2H, Ar-H), 7.67 (s, 1H, NH); 13 C NMR (DMSO-d6, 100 MHz) δ: 109.5, 117.2, 119.5, 122.4,124.6, 126.1, 129.3, 138.2, 142.7, 147.4,158.1;HRMS (ESI) calcd for [M+H] + C13H10ClN2O: 245.
Source: Heterocycles
DOI: 10.3987/com-17-13712
Authors: Guang-cheng Wang, Jing Wang, Lu-yao Li, Shan Chen, Ya-ping Peng, Zhen-zhen Xie, Ming Chen, Bing Deng, Wen-biao Li
Institution: Jishou University
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W2731482693