6-exo versus 7-endo iodolactonizations of 2-(alkynyl)phenylacetic acids

Article abstract of DOI:10.1016/j.tetlet.2008.12.097

Exposure of 2-alkynylphenylacetic acids to excess iodine in acetonitrile containing anhydrous potassium carbonate delivers good yields, either of the corresponding isochroman-3-ones or benzo[d]oxepin-2(1H)-ones, depending upon the alkyne substituent: when