Rapid access to 6-bromo-5,7-dihydroxyphthalide 5-methyl ether by a CuBr2-mediated multi-step reaction: concise total syntheses of hericenone J and 5′-deoxohericenone C (hericene A)

A practical route to 6-bromo-5,7-dihydroxyphthalide 5-methyl ether, a versatile intermediate in the synthesis of hericenones and related bioactive polyphenols, was developed. The synthesis features a combination of tandem Michael addition-Claisen condensation and CuBr2-mediated multi-step reactions. With this product in hand, total syntheses of hericenone J and 5′-deoxohericenone C (hericene A) were achieved.