申请人:Reilly Tar & Chemical Corp.
公开号:US04405790A1
公开(公告)日:1983-09-20
An improved process for preparing the 2-alkylamino-5-alkylpyridine and 2-amino-5-alkylpyridine amination products of 3-alkylpyridines, comprising the step of initially reacting the base directly with the sodium salt of a primary alkylamine to produce the 2-alkylamino form, wherein the alkyl group in each reactant has from 1 to about 20 carbon atoms. The sodium salt is preferably preformed in situ by adding the alkylamine to a dispersion of sodium in an organic solvent heated to about 100.degree.-120.degree. C. The substituted amination preferably proceeds at a temperature of about 100.degree.-140.degree. C. in a solvent such as toluene and under an inert nitrogen atmosphere. The ratio of 2,5-:2,3- isomer products of the reaction is up to about 10:1 or more, with the effective yield of the 2,5-alkylated isomer being about 25% or more. This recovered 2-alkylamino-5-alkylpyridine product is readily dealkylated by reaction with hydrobromic or hydriodic acid with or without the presence of a pyridine hydrohalide salt to obtain the 2-amino-5-alkylpyridine product which has proven uses in herbicidal, insecticidal and pharmaceutical applications.
改进的制备2-烷基氨基-5-烷基吡啶和2-氨基-5-烷基吡啶的3-烷基吡啶氨化产物的方法,包括最初将碱直接与一级烷基胺的钠盐反应以产生2-烷基氨基形式的步骤,其中每个反应物中的烷基组具有1至约20个碳原子。钠盐最好是通过将烷基胺加入加热至约100°C至120°C的有机溶剂中的钠分散体中原位形成的。取代的氨化反应最好在惰性氮气气氛下,在诸如甲苯的溶剂中,以约100°C至140°C的温度进行。反应的2,5-:2,3-异构体产物比率高达约10:1或更高,2,5-烷基化异构体的有效产率约为25%或更高。这种回收的2-烷基氨基-5-烷基吡啶产物可以通过与氢溴酸或氢碘酸反应,有或没有存在吡啶氢卤化物盐的情况下,轻松脱烷基化,以获得2-氨基-5-烷基吡啶产品,该产品已被证明在除草剂,杀虫剂和药物应用中有用。