sulfuric acid; dihydrogen peroxide; tris(cetyl)pyridinium 12-tungstophosphate in ethanol; chloroform 3 h; Heating; Yield given. Further byproducts given. Yields of byproduct given. Title compound not separated from byproducts;
multistep reaction ; other alkynes, other π-donor compounds; selective coupling of alkynes with alkynes, nitriles, or aldehydes with the aid of zirconium complexes;