Highly Selective Dehydroaromatization of n -Alkanes to Aromatics and Hydrogen Gas

Transformation of available and inexpensive alkanes to high-value aromatics and hydrogen gas represents an atom-economical route of great interest. However, concurrent C–C bond scission and recombination side reactions severely challenge the selectivity and efficiency of conventional catalytic systems. Herein, we report a phosphorus-doped carbon (P@C) catalyst that enables the metal-free, acceptorless dehydroaromatization of linear C 6 –C 8 alkanes with exceptional selectivity. The reaction proceeds via a unique β–C–H bond activation pathway, yielding 2-hexene as the primary intermediate, and culminates in a cascade of consecutive dehydrogenation and cyclization steps. This catalyst’s remarkable propensity for selective C–H bond activation over C–C bond cleavage effectively suppresses side reactions. Consequently, n -hexane is converted to benzene with >99% selectivity at 96% conversion, while n -heptane and n -octane are transformed into toluene and C 8 aromatics ( o -xylene, ethylbenzene), respectively, with ∼90% selectivity at near-complete conversion. This work highlights a highly atom-efficient, metal-free catalytic strategy for coproducing aromatics and hydrogen.