Piperidine → HCID 21842236, compound

Participants

Reaction Steps

125 ml of a crude THF solution of 8-fluoro-3-(5-iodomethyl-oxazol-2-yl)-5-methyl-5,6-dihydro-4H-imidazo[1,5-a][1,4]benzodiazepin-6-one (prepared from 15.6 g (0.050 mol) of 8-fluoro-5-methyl-6-oxo-5,6-dihydro-4H-imidazo[1,5-a][1,4]benzodiazepine-3-carboxylic acid prop-2-ynylamide and 16.9 g (0.075 mol) of N-iodosuccinimide, subsequently completely freed from the solvents, dried azeotropically several times with toluene and dissolved in 500 ml of THF) were treated with 10.7 ml (0.109 mol) of piperidine and stirred at room temperature for 3 hrs. The suspension obtained was completely freed from the solvents, the residue was partitioned between ethyl acetate and 1N aqueous hydrochloric acid and extracted. The aqueous-acidic phase was made basic and extracted with ethyl acetate. The organic phase was concentrated, the beige-brown product was chromatographed over silica gel with ethyl acetate/methanol 4:1 as the eluent and recrystallized from hot ethyl acetate. There was obtained 0.85 g (17%) of 8-fluoro-5-methyl-3-(5-piperidin-1-ylmethyl-oxazol-2-yl)-5,6-dihydro-4H-imidazo[1,5-a][1,4]benzodiazepin-6-one as yellowish crystals; m.p. 191-193°.

Provenance & Evidence