Cu / CuxOy NPs结构化的COF:一种可循环利用的催化剂,用于通过大气环化CO2的利用来合成恶唑烷二酮。
摘要:
本研究描述了具有优异的表面积,可调节的孔径和巨大的CO 2捕集效率的结晶共价有机骨架(COF)的有利构造,可通过将CO 2引入反应性极强的有机骨架中来促进新型多组分环化。在催化性Cu / Cu x O y NP负载的COF的存在下,几种2-溴-3-烷基丙烯酸与几种胺衍生物和CO 2(0.1 MPa)的结合以优异的收率转化为所需的恶唑烷二酮。 96%)在无碱条件和环境温度下进行。
Titanocene(III) chloride mediated radical induced addition-elimination route to the synthesis of racemic and optically active trisubstituted tetrahydrofurans: Formal synthesis of magnofargesin and 7′-epimagnofargesin
作者:P CHAKRABORTY、S K MANDAL、S C ROY
DOI:10.1007/s12039-016-1106-0
日期:2016.7
Titanocene(III) Chloride mediated radical induced synthesis of 4-benzylidene substituted tetrahydrofuran, a typical lignan skeleton, has been accomplished in good yield through addition-elimination route in racemic as well as in optically active forms. The method has been applied to the synthesis of furano lignans, magnofargesin (1) and 7′-epimagnofargesin (2) in optically active forms. Titanocene(III)
Chemical fixation of carbon dioxide by copper catalyzed multicomponent reactions for oxazolidinedione syntheses
作者:Siddharth Sharma、Ajay K. Singh、Devendra Singh、Dong-Pyo Kim
DOI:10.1039/c4gc02089h
日期:——
The quest to reduce greenhouse gases has triggered the development of new chemical fixation of carbon dioxide.
减少温室气体排放的探索已经引发了新的化学固定二氧化碳的发展。
α-Hypervalent Iodine Functionalized Phosphonium and Arsonium Ylides and Their Tandem Reaction as Umpolung Reagents
作者:Zhizhen Huang、Xiaochun Yu、Xian Huang
DOI:10.1021/jo026077i
日期:2002.11.1
iodine functionalized phosphonium and arsonium ylides 2 can be used as umpolung ylides to react with nucleophiles to give alpha-heteroatom substituted ylides 4 in good yields. The nucleophilic substitution-Wittig tandem reaction of 2 can occur smoothly to provide an efficient method for the synthesis of (Z)-alpha-halo-alpha,beta-unsaturated enoates or enones 6, stereoselectively.
Versatile Transformations of α,β-Dibromoesters and Ketones in Basic Media under Microwave Irradiation
作者:Jack Hamelin、Aïcha Saoudi、Hadj Benhaoua
DOI:10.1055/s-2003-41054
日期:——
Depending on the reaction medium, α,β-dibromoesters under microwave irradiation may selectively lead to α-bromoalkenes, to alkenes or to (E)-β-bromostyrenes. The corresponding ketones give selectively the α-bromoketones.
Stereoselective Preparation of (<i>E</i>)-α-Bromoacrylates from Mixtures of Brominated Ando Phosphonates
作者:Reinhard Brückner、Thomas Olpp
DOI:10.1055/s-2004-831166
日期:——
We prepared 69:31-11:89 mixtures of phosphonates 6b and 7b containing two phenoxy substituents, a CO 2 Et group, and 1 or 2 bromine atoms, respectively, at the interspersed methylene group. Deprotonating 64:36 mixtures of these reagents with NaH and adding a variety of aldehydes at 0 °C provided unsaturated α-bromoesters. Yields were typically 70-99% and E-selectivities (i.e. ester and β-substituent
我们制备了 69:31-11:89 的膦酸酯 6b 和 7b 混合物,在散布的亚甲基上分别含有两个苯氧基取代基、一个 CO 2 Et 基团和 1 个或 2 个溴原子。将这些试剂与 NaH 的 64:36 混合物去质子化,并在 0 °C 下添加各种醛,得到不饱和的 α-溴酯。产率通常为 70-99%,E-选择性(即酯和 β-取代基顺式)为 80:20-98:2。类似地,我们通过氯化膦酸酯 49 进行到 E:Z = 94:6 (80%) 的不饱和 α-氯代酯 51。