Synthesis of 3-hydroxyalkylbenzo[b]furans via the palladium-catalysed heteroannulation of silyl-protected alkynols with 2-iodophenol

Article abstract of DOI:10.1055/s-1997-1357

The palladium-catalysed annulation of silyl-protected alkynols with 2-iodophenol gives silyl-protected 3-hydroxyalkylbenzo[b]furans 3 a-l. The use of silyl-protected propynols bearing a free hydroxyl or an O-triethylsilyl protecting group resulted in the formation of 1-oxa-2-silacyclopent-3-enes 5a-d as the major products. Removal of the silyl protecting groups from silyl benzo[b]furans 3c, 3e and 3i affords 3-hydroxyalkylbenzo[b]furans 9a-c in good yield.