作者:B. Reddy、A. Naidu、P.K. Dubey
DOI:10.14233/ajchem.2013.13593
日期:——
Reaction of 2-thioquinazolinone (1) with various alkylating agents like dimethyl sulphate, diethyl sulphate and benzyl chloride in the presence of K2CO3 as a mild base, by a simple physical grinding, microwave irradiation and PEG-600 under solvent-free conditions for 10-15 min at room temperature, followed by processing, gave respectively 2-methylsulfanyl-3H-quinazolin- 4-one (2a, i.e., R = CH3), 2-ethylsulfanyl-3H-quinazolin-4-one (2b, i.e., R = C2H5) and 2-benzyl sulfanyl-3H-quinazolin-4-one (2c, i.e., R = PhCH2Cl). It appears from this study that green syntheses such as solid phase synthesis (physical grinding) and microwave irradiation gives better yields, quality and in less reaction time the products over conventional methods involving green solvents like ethanol, PEG-600 etc. The entire sequences of reactions have been carried out using eco-friendly solvents and green conditions.
2-硫喹唑啉酮(1)与各种烷基化试剂(如硫酸二甲酯、硫酸二乙酯和苄基氯)在温和碱K2CO3存在下,通过简单的物理研磨、微波辐射和无溶剂条件下的PEG-600,在室温下反应10-15分钟,经过处理分别得到:
- 2-甲硫基-3H-喹唑啉-4-酮(2a, R = CH3)
- 2-乙硫基-3H-喹唑啉-4-酮(2b, R = C2H5)
- 2-苄硫基-3H-喹唑啉-4-酮(2c, R = PhCH2Cl)
研究表明,绿色合成方法如固相合成(物理研磨)和微波辐射与传统使用乙醇、PEG-600等绿色溶剂的方法相比,能获得更好的产率和质量,且反应时间更短。整个反应序列都采用了环保溶剂和绿色条件。