Carbon-Based Solid Acid as an Efficient and Reusable Catalyst for Cross-Aldol Condensation of Ketones with Aromatic Aldehydes under Solvent-Free Conditions

Aromatic aldehydes undergo cross-aldol condensation with ketones in the presence of carbon-based solid acid under solvent-free conditions to afford the corresponding α,β-unsaturated aldol products in excellent yields. The catalyst is reusable several times without any decrease in the yield of the reactions.