Ethanolamine → HCID 20508555, compound

Participants

Reaction Steps

A dichloroethane solution of [6-(o-fluorophenyl)-1-methyl-4H-s-triazolo[4,3-a][1,4]benzodiazepin-8-yl]-isocyanate, prepared as described in paragraph (a) of Example 1 from 5 g (16.3 mmol) of 8-amino-6-(o-fluorophenyl)-1-methyl-4H-s-triazolo[4,3-a][1,4]benzodiazepine, is added dropwise at room temperature while stirring to a suspension of 6.2 g (58.5 mmol) of sodium carbonate in 3 ml (49.8 mmol) of ethanolamine and 40 ml of acetonitrile. After 20 hours, the mixture is partitioned between 500 ml of water and 500 ml of methylene chloride/ethanol (4:1) at 50° C. The separated aqueous phase is treated again in an analogous manner, the combined organic extracts are dried and concentrated in vacuo. Crystallisation of the residue from ethanol yields 1-[6-(o-fluorophenyl)-1-methyl-4H-s-triazolo[4,3-a][1,4]-benzodiazepin-8-yl]-3-(2-hydroxyethyl)urea of melting point 228°-230° C.

Provenance & Evidence