A fast and simple method for deoxyfluorination of carboxylic acids is presented. The protocol employs commodity chemicals (PPh 3 , NBS, fluoride), affording products in excellent yields under mild conditions. Acyloxyphosphonium ion, the key reaction intermediate, was identified by NMR spectroscopic methods. Brønsted acidic conditions are essential for efficient C−F bond formation. The protocol displays scalability, high functional group tolerance, chemoselectivity, and easy purification of products. Deoxyfluorination of active pharmaceutical ingredients was established.
CO2 adsorbents based on the reaction of pentaethylenehexamine (PEHA) or tetraethylenepentamine (TEPA) with propylene oxide (PO) were easily prepared in “one pot” by impregnation on a silica support in water. The starting materials were readily available and inexpensive, facilitating the production of the adsorbents on a large scale. The prepared polyamine/epoxide adsorbents were efficient in capturing CO2 and could be regenerated under mild conditions (50–85 °C). They displayed a much‐improved stability compared with their unmodified amine counterparts, especially under oxidative conditions. Leaching of the active organic amine became minimal or nonexistent after treatment with the epoxide. The adsorption as well as desorption kinetics were also greatly improved. The polyamine/epoxide adsorbents were able to capture CO2 from various sources including ambient air and indoor air with CO2 concentrations of only 400–1000 ppm. The presence of water, far from being detrimental, increased the adsorption capacity. Their use for indoor air quality purposes was explored.
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