Formation of Dioxolane on the Surface of Silica–Sulphuric Acid in Dry Media—Chemoselective Protection of Aryl Aldehydes

Abstract Chemoselective protection of aryl aldehydes can be accomplished through the formation of dioxolane on the surface of silica–sulphuric acid under solvent‐free conditions where aliphatic aldehydes, dialkyl ketones, aryl alkyl ketones, and diaryl ketones remain intact.