38091-73-5Relevant articles and documents
Overcoming Selectivity Issues in Reversible Catalysis: A Transfer Hydrocyanation Exhibiting High Kinetic Control
Bhawal, Benjamin N.,Ehinger, Christian,Morandi, Bill,Reisenbauer, Julia C.
supporting information, p. 10914 - 10920 (2020/07/13)
Reversible catalytic reactions operate under thermodynamic control, and thus, establishing a selective catalytic system poses a considerable challenge. Herein, we report a reversible transfer hydrocyanation protocol that exhibits high selectivity for the thermodynamically less favorable branched isomer. Selectivity is achieved by exploiting the lower barrier for C-CN oxidative addition and reductive elimination at benzylic positions in the absence of a cocatalytic Lewis acid. Through the design of a novel type of HCN donor, a practical, branched-selective, HCN-free transfer hydrocyanation was realized. The synthetically useful resolution of a mixture of branched and linear nitrile isomers was also demonstrated to underline the value of reversible and selective transfer reactions. In a broader context, this work demonstrates that high kinetic selectivity can be achieved in reversible transfer reactions, thus opening new horizons for their synthetic applications.
Base-Promoted Cascade Approach for the Preparation of Reduced Knoevenagel Adducts Using Hantzsch Esters as Reducing Agent in Water
He, Tao,Shi, Ronghua,Gong, Yimou,Jiang, Guangyou,Liu, Ming,Qian, Shan,Wang, Zhouyu
supporting information, p. 1864 - 1869 (2016/07/16)
A cascade Knoevenagel condensation-reduction approach, which was carried out in water, has been reported. Using Hantzsch esters as reducing agent, under the promotion of base, a variety of reduced Knoevenagel adducts could be easily prepared by direct alkylation of malononitrile, ethyl 2-cyanoacetate, and 2-(4-nitrophenyl)acetonitrile, respectively. Meanwhile, a gram-scale synthesis of the protocol was also realized with excellent isolated yield.
Nano-K2CO3: Preparation, characterization and evaluation of reactive activities
Li, Jun-Zhang,Fan, Shi-Ming,Sun, Xuan-Fei,Liu, Shouxin
, p. 1865 - 1869 (2016/01/20)
A novel base, nano-K2CO3, was easily prepared by ultrafine wet milling. The surface properties and the reactive activities of nano-K2CO3 were characterized. It was found that such a base showed higher basicity than normal K2CO3 and could replace sodium (or potassium) alkoxide to carry out monoalkylation and oximation of active methylene compounds. The nano-K2CO3 could be regenarated and reused 10 times without loss of its reactive activity.
Catalyst-free chemoselective reduction of the carbon-carbon double bond in conjugated alkenes with Hantzsch esters in water
He, Qi,Xu, Zhihong,Jiang, Dehong,Ai, Wensi,Shi, Ronghua,Qian, Shan,Wang, Zhouyu
, p. 8671 - 8674 (2014/03/21)
A simple, efficient and green protocol for chemoselective reduction of carbon-carbon double bond in conjugated alkenes with Hantzsch esters is described. Without any additional catalysts, a series of conjugated alkenes with strong electron-withdrawing groups were reduced in water with excellent yield. Functional groups such as nitrile, ester, nitro, fluoro, chloro, bromo, furanyl and benzyl are all tolerated by the reaction conditions employed. The Royal Society of Chemistry.
Sodium borohydride as the only reagent for the efficient reductive alkylation of malononitrile with ketones and aldehydes
Dunham, Jason C.,Richardson, Adam D.,Sammelson, Robert E.
, p. 680 - 686 (2007/10/03)
An efficient and convenient method for the synthesis of primary and secondary monosubstituted malononitriles has been developed. In this method, sodium borohydride in isopropanol has a catalytic effect on the initial condensation between malononitrile and