RESUMEN
Herein, we developed a synthetic strategy for the direct construction of C-S bonds to obtain biologically active sulfur-containing compounds and a methodology involving the reductive sulfuration of aldehydes or ketones to obtain diverse substituted thiol, disulfide, and thioester derivatives. EtOCS2K is demonstrated as a potential substitute for the Berzelius reagent or Lawesson's reagent for the construction of C-S bonds.
RESUMEN
Herein, the diversity-oriented aromatization of cyclic hydrocarbons via potassium ethyl xanthogenate (EtOCS2K)/NH4I-mediated methylthiyl radical addition and thioether elimination was investigated under transition-metal-free conditions. The methylthiyl radical species were generated in situ via the NH4I-mediated decomposition of DMSO following which EtOCS2K promoted the breaking of carbon-sulfur bonds of thioether.
RESUMEN
Herein, the PdII -catalyzed construction of functionalized dihaloalkenynes from haloalkynes via a self-haloalkynylation reaction, without specialized ligands or oxidizing additives, is reported. The method tolerates a diverse range of haloalkynes, including electron-donating and electron-withdrawing functional groups, such as macrocyclic alkynols, spiro-oxy ring alkynols, and even carbazole-containing, pyrrolidine-2,5-dione-containing and silyl-protected bromoalkynes. Using an opposite lithium halide (LiX) to the haloalkyne starting material, remarkably high regio- and stereoselectivity of the haloalkynylation reaction is possible, yielding 1-bromo-2-chloroalkenyne or 2-bromo-1-chloroalkenyne products as desired.
RESUMEN
A practical protocol has been established to access diverse oxazol-2-amine derivatives in one step via the electrochemical desulfurative cyclization of isothiocyanates and α-amino ketones. On the basis of the cycle of in situ generation of iodine/desulfurative cyclization/iodide anion regeneration, the reaction is performed under metal-free and external-oxidant-free electrolytic conditions to achieve the formation of intermolecular C-O and C-N bonds, providing oxazol-2-amines in moderate to excellent yields.
RESUMEN
A novel electrochemical synthesis protocol has been achieved for reductive amination between aldehydes and amines in undivided cells at room temperature. Under metal-free and external-reductant-free electrolysis conditions, various important secondary amine products are obtained in moderate-to-high yields. Deuterium-labeling experiments have demonstrated that low-toxicity DMSO acts both as a solvent and a H-donor in the reaction. On this basis, various deuterium-labeled products with good-to-excellent D-incorporation have been synthesized by using DMSO-d6 as a solvent. Furthermore, a molecule with GR-antagonistic activity has been synthesized through further sulfonylation.
RESUMEN
A novel vicinal aminotrifluoromethylation of alkenes using CF3SO2Na as a trifluoromethyl precursor and acetonitrile as an N-nucleophile has been achieved by an electrooxidative strategy. The present electrochemical protocol achieves efficient and highly regioselective difunctionalization of C[double bond, length as m-dash]C bonds under metal-free and external oxidant-free electrolysis conditions, leading to a series of ß-trifluoromethylamine compounds with good to excellent yields. It is confirmed that the reaction involves free radical processes since CF3 radicals are trapped by scavengers and the ß-trifluoromethylated radical is trapped by BHT, and the deuterium-labeling experiments prove that the oxygen in the product comes from water.
RESUMEN
An efficient decarboxylative trifluoromethylation of α,ß-unsaturated carboxylic acids using the Langlois reagent as a trifluoromethyl precursor has been achieved by an electro-oxidative strategy. Under catalyst-free and external oxidant-free electrolysis conditions, a series of Cvinyl-CF3 compounds are obtained with a high regioselectivity in good yields. The successful trapping of the CF3 radical by a scavenger has confirmed that radical processes are involved in this system.