SYNTHESIS OF 8-HYDROXY-6-METHOXY- 3-UNDECYLISOCOUMARIN AND 2-HY DROXY - 4-METHOXY-6-(2-OXOTRIDECYL) BENZOIC ACID

Abstract
Straightforward conversion of (+)-6,8-dimethoxy-3,4-dihydro-3-
undecylisocoumarin (3) to the title isocoumarin was carried out. Hydrolytic ring
opening of (3) afforded the hydroxy acid (4) which was immediately oxidized
to keto acid (5) using chromic acid, Cyclodehydration of (5) afforded the 6,8-
dimethoxy-3-undecylisocoumarin (6) which on selective demethylation of 8-
methoxy group furnished the title isocoumarin (2). The title keto acid (1, R=H)
which was obtained by hydrolytic ring opening of title isocoumarin (2) was
esterified to keto ester (1, R=Me)