SYNTHESIS OF ETHYL-6-(2'-HYDROXYISOPROPYL)-7-METHOXYNAPHTHALENE AN ISOMER OF EMMOTIN-G METHYL-ETHER

Ethyl p-methoxystyryl ketone 1 is hydrogenated over Pd-C (5%) to furni sh 5-(p-methoxyphenyl)pentan-3-one 2. The alcohol 3, obtained by Grign ard reaction of methylmagnesium iodide with the ketone 2, is cyclodehy drated with PPA to give 7-methoxy-1,2-dimethyltetralin 4. Acylation of 4 with acetic acid in PPA yields 6-acetyl-7-methoxy-1,2-dimethyltetra lin 5. The tetralin 5 is aromatized with p-chloranil to afford 6-acety l-7-methoxy-1,2-dimethylnaphthalene 6 which on reaction with methylmag nesium iodide furnishes the desired isomer 7 of emmotin-G methyl ether 14.