been developed for the reductive alkylation of malononitrile with aromatic aldehydes. This new procedure has vastly improved the yield and efficiency of the process, and increased the scope of the aromatic aldehydes. Incorporating water as the catalyst in ethanol for the condensation step allows stoichiometric amounts of malononitrile and aldehyde to be employed. The reduction step takes place quickly
Mn-Catalyzed Electrochemical Chloroalkylation of Alkenes
作者:Niankai Fu、Yifan Shen、Anthony R. Allen、Lu Song、Atsushi Ozaki、Song Lin
DOI:10.1021/acscatal.8b03209
日期:2019.1.4
The heterodifunctionalization of alkenes is an efficient method for synthesizing highly functionalized organic molecules. In this report, we describe the use of anodically coupled electrolysis for the catalytic chloroalkylation of alkenes—a reaction that constructs vicinal C–C and C–Cl bonds in a single synthetic operation—from malononitriles or cyanoacetates and NaCl. Knowledge of the persistent radical
Enantioselective Nickel-Catalyzed Reductive Aryl/Alkenyl–Cyano Cyclization Coupling to All-Carbon Quaternary Stereocenters
作者:Zi-Hao Chen、Rui-Ze Sun、Fei Yao、Xu-Dong Hu、Long-Xue Xiang、Hengjiang Cong、Wen-Bo Liu
DOI:10.1021/jacs.2c01237
日期:2022.3.23
An enantioselective nickel-catalyzed intramolecular reductive cross-coupling of C(sp2) electrophiles and cyano groups is reported. Enantioenriched CN-containing all-carbonquaternarystereocenters are assembled by desymmetrizing cyclization of aryl/alkenyl halide-tethered malononitriles. The use of an organic reductant, (EtO)2MeSiH, is crucial to the enantioselectivity and reactivity. Applications
Unprecedented formation of 3-(tetrahydrofuran-2-yl)-4H-chromen-4-one in a reaction between 3,3a-dihydro-9H-furo[3,4-b]chromen-9-one and malononitrile
作者:Jie-Jie Liu、Liang Cheng、Hong-Yan Huang、Feng Wei、Dong Wang、Li Liu
DOI:10.1039/c7ob00904f
日期:——
Chromone skeletons are widespread among natural products as well as bioactive molecules. Here, we describe an unprecedented reaction of furo[3,4-b]chromen-9-one with malononitrile to afford 3-(tetrahydrofuran-2-yl)-4H-chromen-4-ones. Experimental data suggest that a sequence of Michael/retro-Michael/Nucleophilic addition is involved in this unprecedented transformation.
A novel efficient and eco-friendly nanocrystallineZnO catalyst was used for the Knoevenagel condensation and for the reduction of CC double bonds at room temperature in the absence of solvents.