2011-67-8

Dark yellow Solid

Erimin,Sumitomo,Japan,1977

Sedative, hypnotic. Controlled substance.

ChEBI: A nitrazepam which is substituted at positions 1 by a methyl groups. It is used as an anticonvulsant and as a hypnotic for the short-term management of insomnia.

To a suspension of 73.9 g of 1-methyl-5-nitro-3-phenylindole-2-carbonitrile in 1.5 liters of dry tetrahydrofuran is added dropwise a solution of 126 g of boron trifluoride etherate in 220 ml of dry tetrahydrofuran with stirring for 2 hours. After addition, stirring is continued for an additional 3 hours. To the reaction mixture is added dropwise 370 ml of water and then 370 ml of concentrated hydrochloric acid with stirring under ice-cooling.
The resulting precipitate is collected by filtration, washed with water followed by ethanol, and dried to give 56.3 g of crude 2-aminomethyl-1-methyl-5- nitro-3-phenylindole hydrochloride, melting point 263°C to 267°C.
To a suspension of 6.5 g of 2-aminomethyl-1-methyl-5-nitro-3-phenylindole in 65 ml of glacial acetic acid is added dropwise a solution of 6.5 g of chromic anhydride in 6.5 ml of water at 20°C with stirring. The mixture is stirred at room temperature overnight and thereto is added 195 ml of water. To the mixture is added dropwise 100 ml of 28% ammonia water with stirring under cooling. The resultant precipitate is collected by filtration, washed with water and dried to give 5.9 g of a crude product having melting point 135°C to 140°C. Fractional recrystallization from ethanol gives 3.8 g of 1-methyl-7- nitro-5-phenyl-1,3-dihydro-2H-1,4-benzodiazepine-2-one as yellow plates, melting point 153°C to 156°C. Further recrystallization from the same solvent gives pale yellow plates having melting point 156°C to 156.5°C.

Tranquilizer