微波辐射下合成2,6-二甲基-3-芳基-4(1H)-喹啉酮

Synthesis of 2,6-Dimethyl-3-aryl-4(1H)-quinolones under Microwave Irradiation

摘要:

研究了在微波促进下N-对甲苯基乙酰胺与取代苯乙酸经酰化和环化反应合成2,6-二甲基-3-芳基-4(1H)-喹啉酮化合物的方法，反应时间短，产物收率高，操作简便。在微波辐射下，以BF3?Et2O为催化剂，N-对甲苯基乙酰胺与取代苯乙酸发生酰化，80 ℃下反应15 min，以85.7%～91.3%的收率得到中间产物N-(4-甲基-2-(2-芳基乙酰基)苯基)乙酰胺；中间产物在叔丁醇钠/叔丁醇存在下进行环化，微波辐射下回流反应20 min，得到目标产物2,6-二甲基-3-芳基-4(1H)-喹啉酮，收率89.2%～94.3%。用IR、1H NMR和元素分析等确证了目标产物的结构。

Abstract:

A simple and efficient method was developed for the synthesis of 2,6-dimethyl-3-aryl-4(1H)-quinolones via the acylation and cyclization of N-(4-methylphenyl)acetamide with substituted phenylacetic acids under microwave irradiation. The reaction conditions of acylation and cyclization were optimized, and the reaction time was shortened enough. N-(4-Methyl-2-(2-arylacetyl)phenyl)acetamides were synthesized with 85.7%～91.3% yields by the acylation of N-(4-methylphenyl)acetamide and substituted phenylacetic acids using BF3?Et2O as catalyst under the conditions of microwave irradiation, 80 ℃ and 15 min. In the presence of sodium tert-butanolate and tert-butanol, the cyclization of N-(4-methyl-2-(2-arylacetyl)phenyl)acetamides under microwave irradiation and reflux condition were completed within 20 min giving the target compounds 2,6-dimethyl-3-aryl-4(1H)-quinolones in 89.2%～94.3% yields. The structures of the target compounds were identified by IR, 1H NMR spectra and elemental analysis.