A facile synthesis of piperonol is reported from catechol. Reacted catechol with excess dichloromethane in an autoclave under nitrogen atmosphere gave 88 4% 1,3-benzodioxole(1), which is directly chlo romethylated to ...A facile synthesis of piperonol is reported from catechol. Reacted catechol with excess dichloromethane in an autoclave under nitrogen atmosphere gave 88 4% 1,3-benzodioxole(1), which is directly chlo romethylated to yield 90 1% 5-chloromethyl 1,3-benzodioxole(2) by hydrogen chloride saturated triformol. 2 can easily convert to piperonal by treatment with alcoholic solution of Na 2CO 3 in yield of 97 7%. The total yield is 78%.展开更多
4substituted ethyl2methyl6,7methylenedioxy3quinolinecarboxylate was prepared from 3,4methylenedioxy-phenylketones Ⅳ,yield of Ⅳa-Ⅳd is 74～87%.The synthetic route consists of acylation,nitration,...4substituted ethyl2methyl6,7methylenedioxy3quinolinecarboxylate was prepared from 3,4methylenedioxy-phenylketones Ⅳ,yield of Ⅳa-Ⅳd is 74～87%.The synthetic route consists of acylation,nitration,reduction and condensation.Moleculor structures of Ⅳa～Ⅳd were determined by IR,1H NMR and MS.展开更多
在氧气气氛中,硝酸氧化脱羧3,4-亚甲二氧基苯乙醇酸(DMA)后生成的NO很快氧化为NO2,与水作用后生成HNO3和HNO2可以继续参与反应,从而实现了氧气部分替代硝酸氧化脱羧合成洋茉莉醛的过程。在此过程中,NO2起到了O2传送带的作用,而HNO2则是...在氧气气氛中,硝酸氧化脱羧3,4-亚甲二氧基苯乙醇酸(DMA)后生成的NO很快氧化为NO2,与水作用后生成HNO3和HNO2可以继续参与反应,从而实现了氧气部分替代硝酸氧化脱羧合成洋茉莉醛的过程。在此过程中,NO2起到了O2传送带的作用,而HNO2则是反应真正的氧化剂。在低温、低浓度硝酸和亚硝酸钠引发剂存在条件下,考察了反应温度、硝酸浓度、硫酸浓度和反应时间等参数的影响。当n(HNO3)/n(DMA)=0.45且反应温度为331.2 K时,反应65 m in后氧气替代硝酸率达到32.9%,DMA转化率为97.0%,反应选择性为97.0%。根据实验结果,提出了进一步提高氧气替代硝酸率,从而实现O2作为氧化剂、HNO3作为催化剂的绿色过程的设想。展开更多
文摘A facile synthesis of piperonol is reported from catechol. Reacted catechol with excess dichloromethane in an autoclave under nitrogen atmosphere gave 88 4% 1,3-benzodioxole(1), which is directly chlo romethylated to yield 90 1% 5-chloromethyl 1,3-benzodioxole(2) by hydrogen chloride saturated triformol. 2 can easily convert to piperonal by treatment with alcoholic solution of Na 2CO 3 in yield of 97 7%. The total yield is 78%.
文摘4substituted ethyl2methyl6,7methylenedioxy3quinolinecarboxylate was prepared from 3,4methylenedioxy-phenylketones Ⅳ,yield of Ⅳa-Ⅳd is 74～87%.The synthetic route consists of acylation,nitration,reduction and condensation.Moleculor structures of Ⅳa～Ⅳd were determined by IR,1H NMR and MS.
文摘在氧气气氛中,硝酸氧化脱羧3,4-亚甲二氧基苯乙醇酸(DMA)后生成的NO很快氧化为NO2,与水作用后生成HNO3和HNO2可以继续参与反应,从而实现了氧气部分替代硝酸氧化脱羧合成洋茉莉醛的过程。在此过程中,NO2起到了O2传送带的作用,而HNO2则是反应真正的氧化剂。在低温、低浓度硝酸和亚硝酸钠引发剂存在条件下,考察了反应温度、硝酸浓度、硫酸浓度和反应时间等参数的影响。当n(HNO3)/n(DMA)=0.45且反应温度为331.2 K时,反应65 m in后氧气替代硝酸率达到32.9%,DMA转化率为97.0%,反应选择性为97.0%。根据实验结果,提出了进一步提高氧气替代硝酸率,从而实现O2作为氧化剂、HNO3作为催化剂的绿色过程的设想。
