Catalytic Oxidation of Alkanes and Cycloalkanes: Overview

Selective functionalisation of inert C(sp3)–H bonds in alkanes and cycloalkanes remains one of the main challenges in the field of environmentally sustainable chemistry. This review provides a critical assessment of current catalytic strategies, in particular addressing the persistent problem of overoxidation and low selectivity. Going beyond traditional compartmentalised summaries, this work identifies a significant trend towards the integration of non-traditional activation methods, including ultrasonic cavitation, photocatalysis, and nanosecond pulse discharges, in both homogeneous and heterogeneous systems. Key contributions include a comparative analysis of radical control strategies, in particular highlighting how intermediate hydroperoxides can be used to shift reaction pathways towards selectivity of over 97% for alcohols and ketones. In addition, we discuss the emerging role of carbon nanomaterials (e.g., fullerenes and brominated nanotubes) as active electron-rich carriers and catalysts that lower the energy barriers for C–H activation under mild, ‘green’ conditions. The review concludes that the future of scalable hydrocarbon oxidation lies in ‘hybrid’ approaches such as stabilising active metal centres in protective matrices (zeolites, polymers) while using physical stimuli (ultrasound) to overcome diffusion limitations. This unique perspective highlights the transition from purely chemical catalyst design to integrated process intensification, offering a roadmap for energy-efficient and environmentally friendly industrial technologies.