Silica sulfuric acid: a reusable solid catalyst for the synthesis of N-substituted amides viathe Ritter reaction

An efficient and environmentally friendly method for the synthesis of a wide variety of primary amides in high yields viathe Ritter reaction of secondary and tertiary alcohols with nitriles using silica sulfuric acid is reported. Silica sulfuric acid (SSA), which is an air-stable, cost-effective solid acid catalyst could be readily recycled by filtration and reused without any significant loss of activity.