Expedient syntheses of naturally occurring (±)-3-benzylphthalides and (±)-3-aryl-8-hydroxy-3,4-dihydroisocoumarins: Structure revision of the (±)-3-benzylphthalide isolated from Frullania falciloba

Abstract

A simple synthesis of (±)-3-benzyl-7-methoxyphthalides (1b, 1d and 4a–c) from 7-methoxyphthalides (3a–c) and a novel AlCl₃-catalysed conversion of (±)-3-benzyl-7-methoxyphthalides (1d, 4a–c) to 4′-O-methylhydrangenol 5a, 4′,6-O,O-dimethylthunberginol-C 5b and related compounds (5c and 5d) is described.