Synthesis of sulfonic acid functionalized carbon catalyst from glycerol pitch and its application for tetrahydropyranyl protection/deprotection of alcohols and phenols

A novel carbon catalyst with –SO3H, –OH and –COOH functional groups was prepared from glycerol pitch by in situ partial carbonization and sulfonation with sulfuric acid. The activity of the catalyst was investigated through tetrahydropyranylation and dehydropyranylation of a wide variety of alcohols and phenols at room temperature by changing the solvent medium from dichloromethane to methanol. Excellent yields, short reaction times, easy and quick isolation of the products and reusability of the catalyst are the main attractions of this method. The novel carbon catalyst holds great potential in the green chemical processes.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (101 K)Download as PowerPoint slideHighlights► Glycerol pitch-based carbon acid catalyst as a replacement for sulfuric acid. ► The first application for the utilization of glycerol pitch. ► Simple preparation, reusability, water resistance, operational simplicity. ► Catalyst for THP protection and deprotection of alcohols and phenols at RT.