Preparation of hippuryl chloride
10 g of dry hippuric acid are finely powdered, sifted through a very fine sieve, and then added to a solution of 13 g of phosphorus pentachloride in 100 g of acetyl chloride. The whole is violently agitated for two hours. The resulting crystals are collected, washed with dry petroleum ether, and dried in a vacuum desiccator over concentrated sulphuric acid. If desired, they may be further purified by recrystallisation from warm acetyl chloride, but prolonged heating must be avoided, as otherwise decomposition will take place and a yellow substance be formed. At all stages of the preparation moisture should be avoided as far as possible. Colourless needles. On heating, it becomes yellow at about 125, then red, and finally melts indefinitely at higher temperatures. Yield 80%.
Preparation of organic compounds, E. de. Barry Barnett, 65, 1912
2-benzamidoacetyl Chloride, CID11356064