The straightforward organocatalytic insertion of carbon disulfide (CS) into epoxides using either choline chloride () or tetrabutylammonium chloride (TBACl) is reported, for the first time, under solvent-free (neat) conditions. Fine-tuning of our system allowed us to obtain either dithiocarbonates (DTCs) or trithiocarbonates (TTCs) with high efficiency. Additionally, a mechanistic proposal is presented, supported by experimental evidence, DFT calculations and wavefunction analyses.
View Article and Find Full Text PDFAcetylenes are essential building blocks in modern chemistry due to their remarkable modularity. The introduction of heteroatoms, such as pnictogens (X), is one of the simplest approaches to altering the C≡C bond. However, the chemistry of the resultant dipnictogenoacetylenes (DXAs) is strongly dependent on the nature of X.
View Article and Find Full Text PDFInvited for the cover of this issue is the group of Vicente del Amo, Alejandro Presa Soto and Joaquín García-Álvarez (QuimSinSos Group) at the University of Oviedo. The image depicts the use of the Fe -based deep eutectic mixture [FeCl ⋅6 H O/Gly (3:1)] (Gly = glycerol) as both promoter and solvent for the straightforward and selective hydration of alkynes, working under mild (45 °C), bench-type reaction conditions (air) and in the absence of ligands, co-catalysts or co-solvents. Read the full text of the article at 10.
View Article and Find Full Text PDFAn efficient, simple and general protocol for the selective hydration of terminal alkynes into the corresponding methyl ketones has been developed by using a cheap, easy-to-synthesise and sustainable Fe -based eutectic mixture [FeCl ⋅ 6H O/Gly (3 : 1)] as both promoter and solvent for the hydration reaction, working: i) under mild (45 °C) and bench-type reaction conditions (air); and ii) in the absence of ligands, co-catalysts, co-solvents or toxic, non-abundant and expensive noble transition metals (Au, Ru, Pd). When the final methyl ketones are solid/insoluble in the eutectic mixture, the hydration reaction takes place in 30 min, and the obtained methyl ketones can be isolated by simply decanting the liquid Fe -DES, allowing the direct isolation of the desired ketones without VOC solvents. By using this straightforward and simple isolation protocol, we have been able to recycle the Fe -based eutectic mixture system up to eight consecutive times.
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