Journal or Book Title
The Journal of Organic Chemistry
The anions of %cyano- or 3-(pheny1thio)phthalide react with Michael acceptors to afford functionalized naphthydroquinones in good yield. The cyano and phenylthio groups function both as activating groups and as leaving groups. An alternative involves the use of protected o-(carboxymethy1)cyanohydrins. The use of phthalide anions in synthesis is exemplified by total syntheses of kalafungin, pachybasin, and chrysophanol. This methodolgy consititutes a direct and regiospecific approach to polycyclic systems.
American Chemical Society
Kraus, George A.; Cho, Hidetsura; Crowley, Steven; Roth, Bruce; Sugimoto, Hirokiko; and Prugh, Susan, "Phthalide annulation: the synthesis of kalafungin, pachybasin and chrysophanol" (1983). Chemistry Publications. 708.