Abstract: The synthesis of lactones in high yields by the palladium-catalyzed carbonylation reaction of halo alcohols can be effected under mild conditions (1-4 atm CO, 25-60" C) with a high turnover of palladium. Benzyl, allyl, aryl, and vinyl halides containing primary, secondary, or tertiary alcohol groups are readily converted to a variety of lactones, including phthalides and butenolides, by this simple procedure.
