微波辐射合成丙酮缩氨基脲

在微波辐射下,以水合肼、尿素、丙酮为原料,采用一釜两步法合成了丙酮缩氨基脲。用单因素实验法考察了原料配比、微波辐射功率、辐射反应时间等条件对收率的影响。通过测定熔点和 IR 分析对产物进行了表征。结果表明:当 n(水合肼):n(尿素):n(丙酮)=1:2.5:1.1,第一步反应的微波辐射功率为600 W,反应温度100℃,辐射反应时间20 min 时,制得反应中间体氨基脲;第二步氨基脲不经分离,在微波辐射功率500 W,反应温度60℃,辐射反应时间15 min 条件下,丙酮缩氨基脲的收率可达90.08%。

SYNTHESIS OF ACETONE SEMICARBAZONE UNDER MICROWAVE RADIATION

Acetone semicarbazone was synthesized from hydrazine hydrate,urea and acetone under microwave irradiation through two steps in one pot.By a single factor test,effects of reactant ratios, microwave power and irradiation time,etc.on the reaction were studied.Structures of the product were identified by means of micro-melting point measurement and IR spectra.Under the optimal con- ditions of the first step.n(hydrazine hydrate):n(urea)=1:2.5,microwave power 600 W,reac- tion temperature 100 ℃ and irradiation time 20 min,the intermediate semicarbazide aminourea was obtained.Under the optimal conditions of the second step:n(hydrazine hydrate):n(acetone)=1: 1.1,microwave power 500 W,reaction temperature 60 ℃ and irradiation time 15 min,yield of dimon- benzyl oxalate reached 90.08 %.Comparing with the traditional heating method,the proposed method has advantages of simple operation and short reaction time.