The synthesis process of 2-mercapto-5-methoxyimidazo[4,5-b]pyridine, a crucial intermediate of tenatoprazole which is a new proton pump inhibitor, was studied.2,6-Dichloropyridine as raw material was nitrated by nitri...The synthesis process of 2-mercapto-5-methoxyimidazo[4,5-b]pyridine, a crucial intermediate of tenatoprazole which is a new proton pump inhibitor, was studied.2,6-Dichloropyridine as raw material was nitrated by nitric acid/sulfuric acid, and after amination 2-amino-3-nitro-6-chloropyridine was obtained.It then reacted with sodium methoxide to give 2-amino-3-nitro-6-methoxypyridine and the intermediate was reduced by H2 with Raney Ni as catalyst to give 2,3-diamino-6-methoxypyridine.Finally cyclization was finished with carbon bisulfide to give the title compound.The optimal reaction conditions and yield(temperature, time, molar yield) were as follows: nitration,110℃, 8 h, 79.3%; amination, room temperature, 10 h, 87.6%; methoxylation,65℃, 30min, 98.7%; reduction,70℃, 3 h; cyclization, reflux, 4 h, 72.4% (two steps).The melting point of the title compound was the same as that reported in literature, and its structure was confirmed by 1H NMR.展开更多
以5,6-二甲氧基-2-(4-吡啶基)-亚甲基-1-茚酮(Ⅱ)和溴化苄(Ⅲ)为原料,合成盐酸多奈哌齐的关键中间体1-苄基-4-(5,6-二甲氧基-1-茚酮-2-亚甲基)-吡啶(Ⅰ).研究了主要因素对反应的影响,n(Ⅱ)∶n(Ⅲ)=1∶1.3,反应时间60 m in,收率为92.8%....以5,6-二甲氧基-2-(4-吡啶基)-亚甲基-1-茚酮(Ⅱ)和溴化苄(Ⅲ)为原料,合成盐酸多奈哌齐的关键中间体1-苄基-4-(5,6-二甲氧基-1-茚酮-2-亚甲基)-吡啶(Ⅰ).研究了主要因素对反应的影响,n(Ⅱ)∶n(Ⅲ)=1∶1.3,反应时间60 m in,收率为92.8%.经核磁共振谱图分析确认为目标产物.进一步讨论了反应的动力学过程,并建立了动力学方程.展开更多
Poly(2-methoxy-5-(2′-ethylhexyloxy)- p -phenylenevinylene) (MEH-PPV) has been prepared by a liquid/solid two-phase reaction.The liquid phase is tetrahydrofuran containing 1,4-bis(chloromethyl)-2-methoxyl-5-(2′-ethyl...Poly(2-methoxy-5-(2′-ethylhexyloxy)- p -phenylenevinylene) (MEH-PPV) has been prepared by a liquid/solid two-phase reaction.The liquid phase is tetrahydrofuran containing 1,4-bis(chloromethyl)-2-methoxyl-5-(2′-ethylhexyloxy) benzene as the monomer and a certain amount of tetrabutylammonium bromide (TBAB) as phase transfer catalyst (PTC).The solid phase is potassium hydroxide particles with diameters smaller than 0 5 mm.Gelation was found in the polymerization processes.As a result,MEH-PPV is partly soluble because of its large molar mass.Soluble MEH-PPV was obtained by using bromomethylbenzene as retardant regent.The molar mass of soluble MEH-PPV was measured to be 6 4×10 4g/mol.The Structure of polymer was identified by IR,Raman,UV/vis and PL spectra.A thin compact film of MEH-PPV can be formed by spin-coating and it emit a yellow light.展开更多
文摘The synthesis process of 2-mercapto-5-methoxyimidazo[4,5-b]pyridine, a crucial intermediate of tenatoprazole which is a new proton pump inhibitor, was studied.2,6-Dichloropyridine as raw material was nitrated by nitric acid/sulfuric acid, and after amination 2-amino-3-nitro-6-chloropyridine was obtained.It then reacted with sodium methoxide to give 2-amino-3-nitro-6-methoxypyridine and the intermediate was reduced by H2 with Raney Ni as catalyst to give 2,3-diamino-6-methoxypyridine.Finally cyclization was finished with carbon bisulfide to give the title compound.The optimal reaction conditions and yield(temperature, time, molar yield) were as follows: nitration,110℃, 8 h, 79.3%; amination, room temperature, 10 h, 87.6%; methoxylation,65℃, 30min, 98.7%; reduction,70℃, 3 h; cyclization, reflux, 4 h, 72.4% (two steps).The melting point of the title compound was the same as that reported in literature, and its structure was confirmed by 1H NMR.
文摘以5,6-二甲氧基-2-(4-吡啶基)-亚甲基-1-茚酮(Ⅱ)和溴化苄(Ⅲ)为原料,合成盐酸多奈哌齐的关键中间体1-苄基-4-(5,6-二甲氧基-1-茚酮-2-亚甲基)-吡啶(Ⅰ).研究了主要因素对反应的影响,n(Ⅱ)∶n(Ⅲ)=1∶1.3,反应时间60 m in,收率为92.8%.经核磁共振谱图分析确认为目标产物.进一步讨论了反应的动力学过程,并建立了动力学方程.
文摘Poly(2-methoxy-5-(2′-ethylhexyloxy)- p -phenylenevinylene) (MEH-PPV) has been prepared by a liquid/solid two-phase reaction.The liquid phase is tetrahydrofuran containing 1,4-bis(chloromethyl)-2-methoxyl-5-(2′-ethylhexyloxy) benzene as the monomer and a certain amount of tetrabutylammonium bromide (TBAB) as phase transfer catalyst (PTC).The solid phase is potassium hydroxide particles with diameters smaller than 0 5 mm.Gelation was found in the polymerization processes.As a result,MEH-PPV is partly soluble because of its large molar mass.Soluble MEH-PPV was obtained by using bromomethylbenzene as retardant regent.The molar mass of soluble MEH-PPV was measured to be 6 4×10 4g/mol.The Structure of polymer was identified by IR,Raman,UV/vis and PL spectra.A thin compact film of MEH-PPV can be formed by spin-coating and it emit a yellow light.
