View all references and the resultant amides 2 were isolated in 75–99% yield by simple extractive workup. The amides thus obtained were used in the subsequent step without purification. Preliminary cyclization studies were carried out with the 4-iodophenyl carboxamide 2d as substrate. Initial screening experiments revealed that catalytic amounts of carboxylic acids in toluene resulted in no reaction, catalytic MeSO 3 H in toluene or neat MeSO 3 H produced many products, ...
