An acetylene zipper-Sonogashira reaction sequence for the efficient synthesis of conjugated arylalkadiynols

We describe a new approach to the preparation of unsymmetrical arylalkadiynols, which is based on the isomerization of readily available internal alkadiynols into their terminal isomers followed by Sonogashira cross-coupling. The influence of the reaction conditions on the efficiency of the 'acetylene zipper' of alkadiynols is investigated. Unstable terminal diynols are used without isolation in Pd/Cu-catalyzed cross-couplings with iodoarenes bearing either electron-withdrawing or electron-donating substituents.