Ring Opening Reactions of n⁶-Xanthone-n⁵-Cyclopentadienyliron Hexafluorophosphate. A Novel Route to 0, 0′ Disubstituted Benzophenones

Abstract

It has been known for some time that 9-xanthone with nitro substituents at the C-2 and C-7 positions are susceptible to the cleavage at the ether linkage by nucleophiles.¹ However, this route for the synthesis of 0, 0′-disubstituted benzophenones has not been explored because of the need to introduce and remove the activating nitro groups. These observations clearly indicate the necessity of developing a method for making 0, 0′-disubstituted benzophenones. The present paper describes the photolysis of the CpFe+ complexes of 0, 0′-disubstituted benzophenones as a straightforward approach to the synthesis of 0, 0′-disubstituted benzophenones.