Simplified preparation of a graphene-co-shelled Ni/NiO@C nano-catalyst and its application in the <i>N</i>-dimethylation synthesis of amines under mild conditions
作者:Jianguo Liu、Yanpei Song、Xiuzheng Zhuang、Mingyue Zhang、Longlong Ma
DOI:10.1039/d1gc00981h
日期:——
selective synthesis of N-methylated compounds using various functional amines and aldehydes under easy to handle, and industrially applicable conditions. A large number of primary and secondary amines (more than 70 examples) could be converted to the corresponding N,N-dimethylamines with the participation of different functional aldehydes, with an average yield of over 95%. A gram-scale synthesis also demonstrated
An Expedient Route for the Stereoselective Construction of Bridged Polyheterocyclic Ring Systems Using the Tandem “Pincer” Diels−Alder Reaction
作者:Mark Lautens、Eric Fillion
DOI:10.1021/jo9701593
日期:1997.6.1
The tandem "pincer" Diels-Alder reaction, consisting of two consecutive [4 + 2] cycloadditions between two dienes and an acetylenic bis-dienophile, has been applied toward the rapid construction of bridged polyoxacyclic ring systems when furan derivatives are used as the diene components. The study has demonstrated the stereoselectivity (exo-exo adduct), the chemoselectivity ("pincer" vs "domino")
Tertiaryamines, currently obtained from fossil resources by a multi-step synthetic method, are important compounds in both chemical industry and organic transformations. Herein, we demonstrated highly efficient and convenient strategy to various biomass-based tertiaryamines in excellent yields (85–95%) by a direct and consecutive reductive amination of furfural with various amines in one-pot using
目前通过多步合成方法从化石资源中获得叔胺,是化学工业和有机转化中的重要化合物。在此,我们通过使用磷化铑 (Rh 2 P) 催化剂在一锅中将糠醛与各种胺直接和连续还原胺化,以优异的收率 (85-95%) 展示了对各种基于生物质的叔胺的高效和便捷的策略。. 通常,基于生物质的三(2-呋喃甲基)胺以 92% 的产率直接从糠醛和 HCOONH 4中获得一步到位。时间依赖性反应曲线表明,糠胺衍生的席夫碱和仲胺作为连续检测的中间体具有连续的胺化/氢化途径。Rh 2 P 的优越性归因于其优异的低温加氢活性,这在结构上归因于从 P 原子(在 P 封端的 Rh 2 P 上)到其键合和解离的 H 原子的有效电子转移。因此,这项研究强调了一种强大、优雅和有吸引力的基于生物质的叔胺方法,用于胺化学的可持续扩展。
Classical Example of Total Kinetic and Thermodynamic Control: The Diels–Alder Reaction between DMAD and Bis-furyl Dienes
作者:Kseniya K. Borisova、Elizaveta A. Kvyatkovskaya、Eugeniya V. Nikitina、Rinat R. Aysin、Roman A. Novikov、Fedor I. Zubkov
DOI:10.1021/acs.joc.8b00336
日期:2018.4.20
tandem Diels–Alderreaction of activated alkynes and bis-dienes has been revealed. The reaction between bis-furyl dienes and DMAD occurs at 25–80 °C and leads to kinetically controlled “pincer” adducts, 4a,8a-disubstituted 1,4:5,8-diepoxynaphthalenes. On the contrary, only thermodynamically controlled “domino” adducts (2,3-disubstituted 1,4:5,8-diepoxynaphthalenes) are formed in the same reaction at 140
揭示了在活化的炔烃和双二烯串联Diels-Alder反应中发生化学特异性的罕见例子。双呋喃二烯与DMAD之间的反应在25–80°C下发生,并导致动力学控制的“钳子”加合物4a,8a-二取代的1,4:5,8-双环氧萘。相反,在140°C的同一反应中仅形成热力学控制的“多米诺”加合物(2,3-二取代的1,4:5,8-双环氧萘)。加热时,“钳子”加合物可转变成“多米诺”加合物。使用动态1 H NMR光谱计算两种类型反应的速率常数。
Dehydrobenzene in the Reaction of a Tandem [4+2]/[4+2] Cycloaddition with Linear bis-furyldienes
作者:Elizaveta A. Kvyatkovskaya、Polina P. Epifanova、Kseniya K. Borisova、Sophia I. Borovkova、Mikhail S. Grigoriev、Fedor I. Zubkov
DOI:10.1007/s10593-021-03005-2
日期:2021.9
Tandem [4+2]/[4+2] cycloaddition between bis-dienes containing two furan rings and dehydrobenzene as a dienophile was studied. It was shown that dehydrobenzene generated in situ from 2-(trimethylsilyl)phenyl trifluoromethanesulfonate is capable of a facile intermolecular [4+2] cycloaddition to a furan moiety of a diene at room temperature. The next step, that involves intramolecular Diels–Alder reaction