Sodium Bicarbonate → HCID 21265984, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 5.1 g of 2-chloromethyl-8-nitro-6-phenyl-4H-imidazo[1,2-a][1,4]benzodiazepine in 70 ml of dioxan was treated with a solution of 1.54 g of sodium hydrogen carbonate in 30 ml of water and the mixture was stirred at 80° C. for 2.5 h. The mixture was filtered and the filtrate was made weakly acidic (pH 6 to 7) with aqueous 3N hydrochloric acid. The filtrate was evaporated in a vacuum and the residue was taken up in chloroform and water. The chloroform phase was washed with water, dried over sodium sulphate and evaporated in a vacuum. The crystalline residue (3.2 g) was dissolved in chloroform and chromatographed over 130 g of silica gel. With chloroform and with chloroform/ethanol 98:2 there were eluted small amounts of various impurities, with chloroform/ethanol 97:3 and 96:4 there was eluted 8-nitro-6-phenyl-4H-imidazo[1,2-a][1,4]benzodiazepine-2-methanol. After recrystallization from ethanol there were obtained 2.45 g of pure 8-nitro-6-phenyl-4H-imidazo[1,2-a][1,4]benzodiazepine-2-methanol of m.p. 250-251° C. which was converted into the hydrochloride (m.p. 295-297° C.).

Provenance & Evidence