Abstract: Direct mercuration of benzene was achieved with mercuric nitrate in glacial acetic acid, giving phenyl mercuric nitrate as the main product. 200 ml of glacial acetic acid and 34 g of mercuric nitrate were added to a 500 ml three-necked flask fitted with stirrer, reflux condenser and a 200℃ thermometer. The mixture was heated up to about 100℃ with stirring until a clear solution was formed. Then heating was interrupted and the solution cooled down to about 70—80℃, when 80 ml of pore benzene was poured in through the reflux condenser. The reaction was then continued at about 75—85℃ with stirring to near completion within 1—1.5 hours. The reactant was transferred into a distilling flask, acetic acid and excess benzene were recovered by distillation under reduced pressure. The sirupy residue was then poured into cold water under vigorous agitation. The precipitate was collected by filtration and dried at bottom 50—60℃. Crade phenyl mercuric nitrate (m. p. 183°—186℃) obtained weighed approximately 28.4g. It was then purified by extraction with 95% ethanol in a Soxhlet, 26.0 g of phenyl mercuric nitrate (m. p. 188°—190℃ with decomposition) was obtained. Yield against mercuric nitrate was 80.6% of theory.