The palladium-catalyzed hydroarylation and hydrovinylation of tertiary 3-(o-acetoxyaryl)- and 3-(o-benzoyloxyaryl)propynols - A route to 4-aryl- and 4-vinyl-2,2-dimethyl-3-chromenes

The palladium-catalyzed hydroarylation and hydrovinylation of tertiary 3-(o -acetoxyaryl)- and 3-(o-benzoyloxyaryl) propynols provides a regio- and ste reoselective route to allylic alcohols with aryl and vinyl substituents whi ch can be readily converted into the corresponding chromene derivatives. Th e hydroarylation and hydrovinylation reaction is believed to proceed throug h a carbopalladation step whose regiochemistry is primarily controlled by t he directing effect of the tertiary hydroxy group.