Alkyl nitrite-enabled palladium-catalyzed terminal selective oxidative cyclization of 4-penten-1-ols.

Oxidative cyclization of 4-penten-1-ols using a Pd catalyst and n -BuONO or n -BuONO/ p -benzoquinone afforded 3-hydroxy- and 3-methoxytetrahydropyrans via terminal selective nucleophilic attack. The radicals formed from n -BuONO and O 2 operate as critical oxidants and ligands for Pd.