EXPEDIENT SYNTHESIS OF BIOLOGICALLY POTENT ARYLOXYCOUMARINS AND (ARYLOXYIMINO)ETHYLCOUMARINS VIA COPPER(II)-PROMOTED CHAN-LAM COUPLING REACTION

A convenient protocol for the efficient synthesis of aryloxycoumarins and (aryloxyimino) ethylcoumarins is described. The synthetic route developed involves the Cu-promoted C-O and N-O coupling reactions from readily available hydroxycoumarin and (hydroxyimino)ethylcoumarin derivatives in the presence of the catalytic system Cu(OAc)(2)/Et3N. By applying this condition, a series of arylboronic acids have been successfully reacted to afford the coupled products in fair to good yields.