Almarhoon Zainab, Al Rasheed Hessa H, El-Faham Ayman
Department of Chemistry, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.
Chemistry Department, Faculty of Science, Alexandria University, P.O. Box 426, Ibrahimia 12321, Alexandria, Egypt.
ACS Omega. 2020 Nov 19;5(47):30671-30678. doi: 10.1021/acsomega.0c04730. eCollection 2020 Dec 1.
This work represents the use of -3-(3,5-dimethyl-1-pyrazol-1-yl)-3-oxopropanenitrile as a cyanoacetylating agent for the synthesis of cyanoacetamide benzoic acid and benzophenone derivatives by two different methods, namely, conventional heating and ultrasonication. The cyanoacetamide derivatives were subjected to cyclization to produce N-substituted 2-pyridone derivatives under conventional heating and by an ultrasonic method as well. The ultrasonic method afforded the products in less reaction time with high yields and purities compared to the conventional method, as observed from their spectral data. -(4-Carboxy phenyl)-4,6-dimethyl-3-cyano-2-pyridone was coupled with different amino acid esters by the OxymaPure/DIC methodology under traditional and ultrasonic conditions. Again, ultrasonication assisted the coupling step and afforded the products with higher yields and purities compared to the traditional method. Fourier transform infrared spectroscopy, NMR (H and C), elemental analysis, and LC-MS were used to determine the structures of all compounds. Finally, a feature of this protocol is exploring the utilization of ultrasonication as an eco-friendly alternative conventional heating method for -cyanoacylation and synthesis of N-substituted pyridinone derivatives and as a coupling method for the formation of an amide bond, which might be of interest for many researchers.
本研究利用3-(3,5-二甲基-1-吡唑-1-基)-3-氧代丙腈作为氰乙酰化试剂,通过两种不同方法,即常规加热和超声处理,合成氰基乙酰胺苯甲酸和二苯甲酮衍生物。氰基乙酰胺衍生物在常规加热和超声方法下均进行环化反应以生成N-取代的2-吡啶酮衍生物。从光谱数据观察可知,与常规方法相比,超声方法在更短的反应时间内得到了高产率和高纯度的产物。-(4-羧基苯基)-4,6-二甲基-3-氰基-2-吡啶酮在传统和超声条件下通过OxymaPure/DIC方法与不同的氨基酸酯偶联。同样,超声处理辅助了偶联步骤,与传统方法相比,得到了更高产率和纯度的产物。使用傅里叶变换红外光谱、核磁共振(氢谱和碳谱)、元素分析和液相色谱-质谱联用技术确定所有化合物的结构。最后,该方案的一个特点是探索将超声处理作为一种环境友好的替代常规加热方法用于氰基乙酰化反应和N-取代吡啶酮衍生物的合成,以及作为形成酰胺键的偶联方法,这可能会引起许多研究人员的兴趣。