Hydrochloric Acid → HCID 57279629, compound

Participants

Reaction Steps

6.77 g (0.020 mole) of 6-phenyl-8-chloro-4H-s-triazolo[1,5-a][1,4]benzodiazepine-2-carboxylic acid [cp. Example 1(a), (b) and (c)] is suspended in 250 ml of abs. ethanol. While being stirred and refluxed, the solution is saturated with hydrogen chloride gas. The obtained clear solution is refluxed for a further 10 hours, and afterwards concentrated at 40° in vacuo. The residue is dissolved in 100 ml of ice-cold 5% sodium bicarbonate solution and 100 ml of methylene chloride; the organic phase is separated, washed with water, dried over sodium sulphate and concentrated at 40° in vacuo. The crude greasy residue is refluxed for one hour with 100 ml of ether, whereby crystallisation occurs. After cooling to 0°, the crystals are filtered off under suction and washed with ether. 6-Phenyl-8-chloro-4H-s-triazolo[1,5-a][1,4]benzodiazepine-2-carboxylic acid ethyl ester, M.P. 137°-138°, is obtained.

Provenance & Evidence