Mechanistic studies in strongly basic media. Part VII. Mechanism of the base-induced reaction of 9-bromofluorenes in t-butyl alcohol containing thiophenol

Abstract

The rate of conversion of 2,9-dibromofluorene into 2,2′-dibromobifluorenylidene by excess of potassium t-butoxide in t-butyl alcohol is markedly reduced in the presence of thiophenol or of 9-fluorenyl phenyl sulphides. It is shown that this effect is related to the ability of the sulphur-containing additives rapidly to convert the halogenofluorene into the related 9,9′-bifluorenyl-9-yl phenyl sulphide which undergoes β-elimination of thiophenol in the rate determining steps of the reaction.