Phosphorus oxychloride → 5,7-Dimethyl-2-(4-nitrophenyl)imidazo[5,1-f][1,2,4]triazin-4(3H)-one

Participants

Reaction Conditions

Reaction Steps

A solution of 13.76 g (8.13 mmol) of N-{1-[3-(4-nitrophenyl)-5-oxo-4,5-dihydro-1,2,4-triazin-6-yl]ethyl}acetamide from example 5A in 150 ml of 1,2-dichloroethane is treated with 20.87 g (12.69 ml, 136.11 mmol) of phosphoryl chloride while cooling with an ice bath. The mixture is stirred for 4 h at 65° C. After cooling, it is hydrolyzed using aqueous sodium hydrogencarbonate solution. The solvent of the organic phase is removed in vacuo and the residue is purified by flash chromatography (eluent gradient:dichloromethane/methanol 200:1-100:1-50:1).

Provenance & Evidence