Collect. Czech. Chem. Commun. 1982, 47, 838-842

Intermolecular cyclization of o-fuchsones

Milena Píšová and Milan Souček

Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, 166 10 Prague 6


o-Fuchsones formed by dehydrohalogenation of o-hydroxyaryl(diaryl)methyl chlorides with tertiary amines undergo a cyclization to eight-membered dimers of the type head to tail. The dimerization reaction is catalyzed by tertiary amines hydrochlorides involving very likely triarylmethyl cation as intermediates.