Condensation of ethyl 4-hydroxy-2-naphthoate (IV) and chloral hydrate with sulfuric acid followed by methylation, alkaline hydrolysis and decarboxylation gave 4-methoxynaphtho [2, 3-c] furan-1 (3H)-one (II). On the other hand, the methyl ether (V) of (IV) was transformed to 5-methoxynaphtho [1, 2-c] furan-3 (1H)-one (VIII) by a similar sequence of reactions. Synthesis of (VIII) by another route starting from ethyl 1-methyl-4-hydroxy-2-naphthoate gave a synthetic confirmation to the structure of (VIII).
