o-Benzenedisulfonimide as a Reusable Brønsted Acid Catalyst for Ritter-Type Reactions

Reactions between various benzyl alcohols or tert-butyl alcohol and nitriles were carried out in the presence of catalytic amounts (usually 10–20 mol-%) of o-benzenedisulfonimide as a Brønsted acid catalyst; the reaction conditions were mild and the yields of amides were good. The catalyst was easily recovered and purified, ready to be used in further reactions, with economic and ecological advantages