Halomethyl-metal compounds LV. The synthesis of phenyl(trifluoromethyl)mercury by fluorination of phenyl(tribromomethyl)mercury

Abstract

The reaction of phenylmercuric hydroxide with aqueous hydrofluoric acid gives a material which appears to be an HF adduct of phenylmercuric fluoride (“PhHgF·HF”). This material has been found to fluorine phenyl(tribromomethyl)-mercury in benzene or toluene medium at room temperature to give phenyl(trifluoromethyl)mercury in yields avaraging 60–65% when the reaction is carried out in the presence of 48% HF. Phenyl(trichloromethyl)mercury can be fluorinated to PhHgCF3 in this manner, but a reaction temperature of 90° is required. Partial fluorination in good yield of phenyl(bromodichloromethyl)mercury to phenyl-(fluorodichloromethyl)mercury could be achieved at room temperature, but attempted partial fluorination of PhHgCBr3, PhHgCClBr2 and PhHgCFBr2 was unsuccessful, PhHgCF3 being the major product obtained. The possible mechanism of this novel fluorination process is discussed.