SO3H-bearing mesoporous carbon with highly selective catalysis

A SO3H-bearing mesoporous carbon material was investigated as a new type of heterogeneous catalyst. Carbonization of resorcinol–formaldehyde resin at 773 K, followed by sulfonation results in amorphous carbon consisting of graphene with high densities of SO3H (0.9 mmol g−1) and phenolic OH (2.0 mmol g−1) groups. The mesoporous carbon that has a large surface area (433 m2 g−1) due to uniform mesopores (ca. 10 nm) exhibits remarkable catalytic performance for the selective dimerization of α-methylstyrene (AMS); the selectivity for unsaturated AMS dimers exceeds 99%. This catalysis is attributed to not only the large surface area based on large mesoporosity, but also to preventing intramolecular Friedel–Crafts alkylation.

Graphical abstractSO3H-bearing mesoporous carbon selectively converts AMS into unsaturated dimers (ca. 99%). The high catalytic performance of the mesoporous carbon is attributed to the large surface area and mesoporosity, which provides high accessibility of hydrophobic reactants to SO3H, and a high density of phenolic OH groups bonded to the carbon that prevent side reactions.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► SO3H-bearing mesoporous carbon was prepared by sulfonation of carbonized RF resin. ► The material can selectively convert α-methylstyrene into unsaturated dimers. ► High catalytic performance can be due to the large surface area and mesoporosity. ► High density of phenolic OH bonded to carbon sheets prevents side reactions.