1-苯基吲哚的合成

摘要

In this paper,n-phenylaniline and oxalyl chloride were used to prepare 1-phenylindole. The experimental conditions,such as material ratio,reaction time,the amount of catalyst and so on were investigated. The optimal conditions of the coupling reaction were found as:n(n-phenyl -aniline)∶n(oxalyl chloride)=1∶3,reaction temperature 20-25 ℃,reaction time 2.5 h,under which the yield of 1-(diphenylamino)-2-chloro-ethanedione was up to 98.02%based on n-phenyl-aniline and the purity was 97.68%as determined by HPLC. The best reaction conditions for preparing 1-phenyl isatin were found as:n(1-(diphenylamino)-2-chloro-ethanedione)∶n(Anhydrous AlCl3)=1∶3,reaction temperature 10 ℃, reaction time 2 h,under which the yield of 1-phenylisatin was 86.76% based on 1-(diphenylamino)-2-chloro-ethanedione and the purity was 98.45% as determined by HPLC. The reduction reaction conditions were optimized as:n(1-phenylisatin)∶n(sodium borohydride) = 1∶3,n(1-phenylisatin)∶n(zinc chloride)=1∶0.05,reaction temperature 110 ℃,reaction time 12 h,under which the yield of 1-phenylisatin was 72.41%based on 1-phenylisatin and the purity was 98.14%as determined by HPLC. The structures of the product were identified by 1H NMR,MS and Micro melting point instrument.%以二苯胺和乙二酰氯为起始原料经偶联、酰化、还原反应得到1-苯基吲哚，并探索了其影响因素。结果表明合成中间体N,N-二苯基-2-氯-2-氧代乙酰胺的较佳条件为：n(二苯胺)：n(乙二酰氯)=1∶3，反应温度20～25℃，反应2.5 h，收率98.02%，HPLC 纯度97.68%；产品1-苯基靛红的较优合成工艺条件为： n(N,N-二苯基-2-氯-2-氧代乙酰胺)：n(无水AlCl3)=1∶3，反应温度10℃，反应时间2 h，收率86.76%，HPLC纯度98.45%；目标产物1-苯基吲哚的最佳工艺条件为：n(1-苯基靛红)：n(硼氢化钠)=1∶3，n(1-苯基靛红)：n(氯化锌)=1∶0.05，反应温度110℃，反应时间12 h，收率72.41%，HPLC纯度98.14%。产品及中间体结构经1H NMR、MS和显微熔点仪分析表征确认。