Mechanism of O2/NO-Promoted Oxidative C-C Bond Cleavage in Linear Alkanes.

Selective oxidation of alkanes to oxygenated products remains a fundamental challenge, particularly if the goal is to promote C-C bond cleavage while minimizing formation of CO2. Oxidation conditions that use O2 and nitrogen oxides (NOx) have been shown to be very effective in promoting radical-mediated functionalization and oxidative carbon-carbon cleavage in saturated hydrocarbon polymers, such as polyethylene. Here, we investigate the mechanism of O2/NO-mediated oxidation of n-decane as a prototypical linear alkane substrate. These reactions enable identification and quantification of reactive intermediates, including nitrites, nitrates, alcohols, and ketones. Under the reaction conditions, these species convert into common ketone intermediates that evolve into α-diketones and other α-functionalized ketones, which undergo further conversion into carboxylic acids. Infrared (IR) spectroscopy indicates that HDPE oxidation proceeds through similar key intermediates. Together, these findings establish a mechanistic framework for NOx-mediated alkane oxidation and provide a foundation for the development of broadly applicable oxidative transformations.