In situ synthesis of 2-allyloxy-1-methylpyridinium triflate for the allylation of carboxylic acids

2-Allyloxypyridinium triflate is formed in situ by treating a mixture of 2-allyloxypyridine, a carboxylic acid, and toluene with methyl triflate. Subsequent warming of the reaction mixture in the presence of potassium carbonate leads to efficient formation of allyl esters in good to excellent yields.