Reactions of the 9-mesityl-9-boraanthracene anion

Abstract

The synthesis of 9-mesityl-9,10-dihydro-9-boraanthracene is described. Proton abstraction with organolithium reagents gave the title anion, which was converted with various electrophiles into derivatives substituted at C-10. UV spectra indicated the absence of intramolecular coordination of oxygen-containing substituents at C-10 to the Lewis acidic boron centre. The preparation and some properties of the fulvenoid 9-mesityl-10-methylene-9,10-dihydro-9-bora-anthracene and its reaction with tert-butyllithium are reported.