Boron trifluoride → Oxcarbazepine

Participants

Reaction Steps

31.5 g (0.12 mole) of 5-cyano-10-nitro-5H-dibenz[b,f]azepine are suspended in 340 ml of chlorobenzene and 98 ml of a solution of 10% by weight of BF3 in acetic acid are quickly added. By heating to 30° dissolution occurs and shortly after that the BF3 adduct of 5-carbamoyl-10-nitro-5H-dibenz[b,f]azepine begins to precipitate. The mixture is left to crystallise for 2 hours in an ice-bath, suction-filtered and washed with benzine. The dry intermediate is dissolved in a mixture of 200 ml of acetic acid and 35 ml of water. 50 g of iron powder are added in portions over a period of 30 minutes and the temperature is maintained at approximately 60° by cooling. The mixture is stirred for a further hour at 50°, filtered and then washed with acetic acid. The filtrate is concentrated by evaporation in vacuo and the residue is taken up in 500 ml of water. The precipitated product is suction-filtered, washed neutral with water and dried in vacuo at 50°. 5-Carbamoyl-10-oxo-10,11-dihydro-5H-dibenz[b,f]azepine is obtained, which according to the IR spectrum is identical to authentic material.

Provenance & Evidence