APPLICATION OF DITHIOESTER REACTIONS WITH GRIGNARD-REAGENTS TO CARBON-CARBON BOND FORMATION - SYNTHESIS OF EGOMAKETONE AND AR-TURMERONE

The addition of alkyl-and allylmagnesium halides to dithioesters can occur respectively in a thiophilic and carbophilic manner. We have shown previously that these two regioselective reactions occur, under appropriate experimental conditions, in nearly quantitative yields and can be usefully applied in organic synthesis. In particular, we developed various paths for the preparation of β-unsaturated ketones and achieved a convenient synthesis of isoartemisia and artemisia ketones from a β-unsaturated dithioester.105 Herein we describe a convenient synthesis of egomaketone (3), perillene (4), iso-ar-turmerone (7), and ar-turmerone (8). © 1979, American Chemical Society. All rights reserved.