FeIII -Based Eutectic Mixtures as Multi-task and Reusable Reaction Media for Efficient and Selective Conversion of
Marina Ramos-Martín1, Nicolas Ríos-Lombardía1,2, Javier González-Sabín2
1Laboratorio de Química Sintética Sostenible (QuimSinSos), Departamento de Química Orgánica e Inorgánica, (IUQOEM), Centro de Innovación en Química Avanzada (ORFEO-CINQA), Facultad de Química, Universidad de Oviedo, E33071, Oviedo, Spain.
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Invited 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 FeIII -based deep eutectic mixture [FeCl3 ⋅6 H2 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 10.1002/chem.202301736.
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02:43E1 Reaction: Stereochemistry and Regiochemistry
02:45E2 Reaction: Kinetics and Mechanism
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02:34Preparation of Alkynes: Dehydrohalogenation
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The acidic strength of hydrocarbons follows the order: Alkynes > Alkenes > Alkanes. The strength of an acid is commonly expressed in units of pKa — the lower the pKa, the stronger the acid. Among the hydrocarbons, terminal alkynes have lower pKa values and are, therefore, more acidic. For example, the pKa values for ethane, ethene, and acetylene are 51, 44, and 25, respectively, as shown here.