changes the standard reaction pathway a of 1 in solution toward nucleophiles completely: the chlorinated N-vinylpyridinium salts 11 and 12 were formed after the reaction of 10 with pyridine or triphenylphosphane. These are useful intermediates for the synthesis of new N- and 4-substituted 1,4-dihydropyridines 13-15 as could be demonstrated for compound 11. To explain the reactivity pattern of compounds
Reaction of Dichloromethane with Pyridine Derivatives under Ambient Conditions
作者:Alexander B. Rudine、Michael G. Walter、Carl C. Wamser
DOI:10.1021/jo100276m
日期:2010.6.18
Pyridine derivatives and dichloromethane (DCM) are commonly used together in a variety of different applications. However, DCM slowly reacts with pyridine and a variety of other representative pyridine derivatives to form methylenebispyridinium dichloride compounds under ambient conditions. The proposed mechanism (two consecutive SN2 reactions) was studied by evaluating the kinetics of the reaction
吡啶衍生物和二氯甲烷(DCM)通常在各种不同的应用中一起使用。然而,DCM在环境条件下与吡啶和多种其他代表性的吡啶衍生物缓慢反应以形成亚甲基双吡啶二氯化物化合物。所提出的机制(两个连续的小号Ñ 2个反应)通过评价4-(二甲氨基)吡啶和DCM之间的反应的动力学研究。发现第一次(k 1)和第二次(k 2)取代的二阶速率常数为2.56(±0.06)×10 -8和4.29(±0.01)×10 -4 M -1 s -1, 分别。因为第二个替换的速度比第一个快得多,所以在反应过程中无法分离或检测到单取代产物。它是独立合成的,目的是观察其动力学。