Conversion of Methane, Ethane and Propane to Form Alkyl Esters: Oxy-Esterification As a Strategy for Selective Partial Oxidation

The selective and low temperature conversion of light alkanes (methane, ethane and propane) to functionalized products has been a long-standing challenge. In protic media, the reaction of light alkanes with iodine oxides results in the conversion to mono-functionalized products with alkyl trifluoroacetates as the primary products. The transformations are effective over a broad range of temperatures (100 - 235 ºC) and pressures (240-6900 kPa) in non-superacidic media. Alkane conversions between 15% and 40% with selectivity for mono-functionalized products between 85% and 95% have been achieved. The presentation will focus on mechanistic studies that incorporate selectivity patterns and kinetic isotope effects for conversion of light alkanes and model hydrocarbons (e.g., adamantane), spectroscopic identification of reaction intermediates, and computational modeling. In addition, preliminary efforts to extend the reaction to photo-mediated conversions as well as thermal processes with non-iodine based oxidants will be presented.