Synthesis of (±)-licarin B and eupomatenoids-1 and -12: A general approach to 2-aryl-7-alkoxy-benzofuranoid neolignans

New syntheses of the title compounds are described using Lewis acid-promoted reactions of styrenes with N-phenylsulfonyl-1,4-benzoquinone monoimines to regioselectively form the 2-arylbenzofuranoid ring system followed by conversion of the aromatic N-phenylsulfonyl moiety into a propenyl substituent.