[摘要]:The synthesis of alkylated 6-hydroxyisochromenes and alkylated 6-hydroxyisocoumarins from 3-ethoxycyclohex-2-en-1-one was developed. The key reaction features a novel intramolecular hydroalkoxylation of a cyclohex-2-en-3-yn-1-one to assemble the dihydropyran moiety. Aromatization of the cyclohex-2-en-1-one ring used a selenylation/oxidative elimination sequence. The isochromenes were oxidized to their isocoumarin analogues using DDQ. |