Sulfuric Acid → Phenylbenzoin

Participants

Reaction Steps

168.18 g (1.0 mole) of benzil in 2 liters of ethyl ether was placed in a 5 liter, three necked round bottomed flask, fitted with a reflux condenser, mechanical stirrer, addition funnel and nitrogen bypass. All of the glassware was flame-dried before use while being flushed with nitrogen. A 3 molar solution in ethyl ether of phenyl magnesium bromide (181.23 g, 1.0 mole) was then placed in the addition funnel and added dropwise to the flask over a period of 1.5 hours. The solution was then refluxed overnight. Hydrolysis of the Grignard complex was then accomplished using a 10% solution of H2SO4 with the concurrent addition of 1.5 liters of CHCl3. After complete hydrolysis, the organic layer was separated and washed with one liter of water. The organic layer was dried with magnesium sulfate, concentrated and recrystallized with hexane to give phenylbenzoin (m.p. 87°-88°, lit 88° C) of 99% purity in yield of 62%.

Provenance & Evidence