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Conventional methods for the production of ketones and aldehydes are usually quite complicated and require the use of specific catalysts. Thus, methyl ethyl ketone (MEK) is currently manufactured through a two-step catalytic process involving the hydration of n-butenes and dehydration of the formed alcohol. The non-catalytic oxidation of olefins with nitrous oxide (N2O) via the 1,3-dipolar cycloaddition mechanism opens a potential route for the direct synthesis of carbonyl compounds. In this work, the oxidation of the commercial butene–butane mixture (BBM) with N2O in the liquid phase at 220–260 °C and elevated pressure was studied using the gas chromatography, gas chromatography–mass spectrometry, and nuclear magnetic resonance analytical methods. It was shown that only butene isomers in BBM are selectively oxidized by N2O to yield ketones and aldehydes with a total selectivity of up to 86.6%, including MEK as the major product. During oxidation, alkyl-substituted cyclopropanes are also formed from butenes with a selectivity of up to 15%.

ATR-FTIR spectroscopy was used in situ to study nine unsaturated polyketones derived from cis-1,4-polybutadiene rubber, each containing a different concentration of carbonyl groups, under high-pressure CO2conditions (up to 100 bar). The study was aimed to systematically determine the relationship between the concentration of carbonyl groups in the polyketones and their ability to absorb CO2and swell. A linear relationship between increasing carbonyl concentration and the overall degree of swelling and CO2sorption was observed for polyketones with a concentration of carbonyl groups below a specific value based on quantitative analysis from the ATR-FTIR spectra. However, polyketones, which had the highest concentration of carbonyl groups, did not follow this correlation. Instead, there was evidence of intermolecular interactions between the carbonyl groups in the polymer chains, which decreases the total CO2sorption capacity and inhibited swelling. The effect of the different molecular weights of polymer was also studied with respect to polyketone swelling and CO2sorption. No correlation was observed when comparing polymers with different molecular weights but contained a similar concentration of carbonyl groups. Hence, the main physical properties that affect the overall swelling and CO2sorption into polyketone samples were quantitatively determined using ATR-FTIR spectroscopy.