A highly enantioselective isocyanide-based multicomponent reaction catalyzed by a chiral N,N′-dioxide/MgII complex was reported. A wide range of substrates were tolerated in this reaction, including alkyl- and aryl-substituted isocyanides with alkylidene malonates and various phenols, affording the corresponding phenoxyimidate products in good to excellent yields (up to 94% yield) with good to excellent
报道了一种由手性N , N ' -二氧化物 / Mg II 配合物催化的高对映选择性异氰化物基多组分反应。在该反应中可以耐受多种底物,包括烷基和芳基取代的异氰化物与亚烷基丙二酸酯和各种酚,以良好至极好的产率(高达 94% 的产率)提供相应的苯氧基亚胺酸酯产物,具有良好至极好的对映选择性(高达到 95.5: 4.5 er)。提出了催化循环和过渡态来合理化反应过程和对映控制。
Reductive Dimerization of Alkylidenemalonates Using Samarium(II) Diiodide and 1H-NMR Behavior of the Dimers, 2,3-Diaryl-1,1,4,4-butaneteracarboxylates.
Alkylidenemalonates were readily dimerized in the presence of SmI2 to give 2,3-disubstituted 1,1,4,4-butanetetracarboxylates as mixtures of meso and racemic isomers in moderate to good yields. The structure of the less polar isomer of tetraethyl 2,3-diphenyl-1,1,4,4-butanetetracarboxylate was determined by X-ray crystallographic analysis to be the meso form. Characteristic 1H-NMR behavior of the meso
environmentally friendly procedure was developed for the Knoevenagel condensation of aromatic aldehydes with diethylmalonate in the presence of FeCl3 and N-fluorobenzenesulfonimide as a source of electrophilic fluorine under solvent-free conditions. The scope of the reaction was explored using commerciallyavailable substrates. The reaction with substituted salicylaldehydes afforded the corresponding coumarin derivatives