Direct imine formation by oxidative coupling of alcohols and amines using supported manganese oxides under an air atmosphere
作者:Bo Chen、Jun Li、Wen Dai、Lianyue Wang、Shuang Gao
DOI:10.1039/c4gc00336e
日期:——
Manganese oxides loaded on various supports have been prepared and studied for the direct imine formation by oxidative coupling of alcohols and amines. Among the catalysts, hydroxyapatite supported manganese oxides (MnOx/HAP) show the best activity and selectivity for this reaction in the absence of an additional base using air as the environmentally benign terminal oxidant. NH3-/CO2-TPD results show
已经制备了负载在各种载体上的锰氧化物,并研究了通过醇和胺的氧化偶联直接形成亚胺的方法。在这些催化剂中,羟基磷灰石负载的锰氧化物(MnO x / HAP)在没有使用空气作为环境友好的终端氧化剂的附加碱的情况下,对于该反应表现出最佳的活性和选择性。NH 3- / CO 2 -TPD结果表明,MnO x的两性性质/ HAP对于该反应获得令人满意的收率至关重要。各种芳族醇和胺均以良好或优异的收率平稳地转化为相应的亚胺。该催化剂可重复使用,并且在所有9次重复使用测试中均可提供98%的产品收率。与新鲜催化剂相比,经过九次反应后,再活化的MnO x / HAP的XRD和SEM没有明显变化。
reaction sequence a primary amine is formed in situ from the corresponding nitro compound. Reversible condensation with aldehydes forms the respective imines, which are finally reduced to the desired secondary amine. This synthesis of secondary amines is atom‐economical and environmentally attractive using cheap and readily available organic compounds as starting materials.
Hydroboration of nitriles and imines by highly active zinc dihydride catalysts
作者:Xiaoming Wang、Xin Xu
DOI:10.1039/d0ra09648b
日期:——
Eco-friendly zinc dihydrides stabilized by N-heterocyclic carbenes were demonstrated to be highly efficient catalysts for the double hydroboration of nitriles with pinacolborane, exhibiting turnover frequencies up to 3000 h-1 at room temperature under solvent-free conditions. The reactions afforded corresponding diboronated amines with excellent yields and good functional group tolerance. A single