Tetrafluoroboric acid → HCID 20523280, compound

Participants

Reaction Steps

A solution of 5 g (22 mmol) of 3-amino-4,5-dihydro-5-methyl-6H-imidazo[1,5-a][1,4]benzodiazepin-6-one in 100 ml of hydrofluoboric acid (50 percent in water) is diazotized at 0° to 5° with a solution of 1.95 g (28 mmol) of sodium nitrite in 4 ml of water. The yellow solution is stirred in an ice-bath for 20 minutes, diluted with 85 ml of hydrofluoboric acid, poured into a quartz vessel and irradiated overnight with a UV-lamp. Subsequently, the mixture is extracted with chloroform. The chloroform extracts are washed with water, dried over magnesium sulphate and evaporated. By chromatography of the residue on a silica gel column there is obtained 3-fluoro-4,5 -dihydro-5-methyl-6H-imidazo[1,5-a][1,4]benzodiazepin-6-one of melting point 171°-172°.

Provenance & Evidence