Sodium borohydride reduction of adducts of primary amines with aldehydes and p-thiocresol. The alkylation of heterocyclic and aromatic amino-compounds
作者:�znur Kemal、Colin B. Reese
DOI:10.1039/p19810001569
日期:——
solution to give N-(p-tolythiomethyl) derivatives [corresponding to the general formula (4; R2= H)], usually in high yields. When the latter compounds are heated, under reflux, with an excess of sodiumborohydride in ethanol or 1,2-dimethoxyethane solution, the corresponding methylamino-compounds [general formula (5; R2= H)] are obtained. By a similar two-step procedure in which aqueous formaldehyde is
对硝基苯胺,2-氨基吡啶(1a),4-氨基吡啶(2a),2-氨基-4-甲基嘧啶(8a),2-氨基噻唑(10a)和2-氨基苯并咪唑(12a)与甲醛水溶液反应,对-通常在高收率下在乙醇或甲醇溶液中用硫代甲酚制得N-(对甲苯硫基甲基)衍生物[对应于通式(4; R 2 = H)]。当后一化合物在乙醇或1,2-二甲氧基乙烷溶液中与过量的硼氢化钠加热回流时,相应的甲氨基化合物[通式(5; R 2= H)]。通过其中的甲醛水溶液被替换,酌情无水乙醛,丙醛,苯甲醛或类似的两个步骤,p硝基苯胺转化成Ñ乙基p硝基苯胺,p -chloroaniline被转换成p氯代N-(正丙基)苯胺,(1a)分别转化为相应的乙基氨基和苄基氨基化合物(1c)和(1d),(10a)和(12a)转化为它们的2- N-(正丙基)衍生物(10c)和(12c)。
Copper-catalyzed amination of an α-C(sp<sup>3</sup>)–H bond in inactivated ethers to synthesize α-aminonitriles
copper-catalyzed functionalization of inert cyclic ethers was developed to provide α-aminonitriles via a cascade oxidation/amination/ring-opening/cyanation reaction. A series of highly versatile α-aminonitriles were obtained from primary or secondary anilines, and heterocyclic and aliphatic amines with high yields. This process features excellent functional group tolerance, a broad substrate scope, and high
selective methods, but the re- action conditions are somewhat harsh, as strong reducing reagents must be used. Nowadays, the formation of C-N bonds via cross- coupling reactions is an essential methodology for the preparation of nitrogen-containing compounds. Recently, different transition-metal-promoted reactions have been developed for the synthesis of secondary amines: catalytic systems for N-alkylation
介绍了一种简单的铜促进的苯胺 N-单烷基化,它利用烷基硼酸作为烷基化伙伴。该反应在回流的二恶烷中进行,它允许在一个步骤中对许多结构和电子不同的苯胺进行官能化。进行了广泛的研究以证明这种新方法在制备苯乙基苯胺方面的实用性。芳香胺是生物活性化合物,广泛存在于制药和农业化学工业中。1 因此,开发新的合成方法仍然是一个活跃的研究领域。特别吸引人的是广泛使用的初级苯胺转化为相应的次级苯胺。直接烷基化通常通过在碱存在下与烷基卤或类似试剂反应来完成。这似乎是一个简单的转化,但在许多情况下,由于过度烷基化,伯苯胺的有效 N-单烷基化是不可能的,这会提供叔苯胺或季铵盐作为副产物。其他制备单烷基化苯胺的方法基于使用允许引入单个烷基的临时保护基团(例如氨基甲酸酯、苄基),然后去除保护基团(引入两个额外的步骤)过程)。然而,由于它们的毒性,必须避免使用许多烷化剂,尤其是在 API 和活性化合物合成的最后一步。羰基
Titanium‐Catalyzed Hydroaminoalkylation of Ethylene
The first examples of titanium-catalyzed hydroaminoalkylation reactions of ethylene with secondary amines are presented. The reactions can be achieved with various titanium catalysts and they do not require the use of high pressure equipment. In addition, the first solid-state structure of a titanapyrrolidine that is formed by insertion of an alkene into the Ti-C bond of a titanaaziridine is reported