Nitro-, arylazo-, and amino-glyoxalines / by Robert George Fargher and Frank Lee Pyman.

  • Fargher, Robert George.
Date:
[1919?]
Catalogue details

Licence: In copyright

Credit: Nitro-, arylazo-, and amino-glyoxalines / by Robert George Fargher and Frank Lee Pyman. Source: Wellcome Collection.

    18/44 (page 234)
    Part II. Nitroglyoxalines. 4:-Nitro glyoxaline. Rung and Behrend (loc. cit.) prepared 4-nitroglyoxalin© in a yield of 36 per cent, of the theoretical by boiling glyoxaline with a mixture of nitric and sulphuric acids. The yield can be improved greatly by the method given below. Eight grams of glyoxaline were dissolved in 16 c.c. of nitric acid (D 1*4), cooled, and 16 c.c. of sulphuric acid cautiously added. A vigorous reaction ensued, and when this had subsided the mixture was boiled gently for two hours, allowed to cool, and then poured into ice-water, when 7*85 grams of 4-nitroglyoxaline separated. The mother liquors yielded a further 0*5 gram of 4-nitroglyoxaline identical with the above, but no glyoxaline and merely a trace of other crystalline material. The total yield of 4-nitroglyoxaline thus amounted to 63 per cent, of the theoretical. 4-Nitrogly ox aline crystallises from boiling acetic acid or from alcohol in stout, rhombic prisms, which are anhydrous and melt at 312—313° (corr.) (Found: N = 36'8. Calc.: N = 37*l per cent.). It is only very sparingly soluble in boiling water. Although it dissolves in strong mineral acids, it is pre¬ cipitated unchanged on the addition of water, and is recovered unchanged when crystallised from aqueous picric acid. 4-Nitro-2~methylglyoxaline was similarly prepared. It crystal¬ lises from water in fine needles, which are anhydrous and melt at 254° (corr.), sintering from 251°. Found: N = 33-0. C4H502N3 (127-1) requires N = 33’l per cent. b-Nitro-4-methylglyoxaline was prepared by Windaus (loc. cit.) in a 60 per cent, yield by warming 4-methylglyoxaline with fuming nitric acid at 80°. Using this method, we found the main pro¬ duct to be 4-methylglyoxaline nitrate. Proceeding according to the method described for 4-nitro-2-methylglyoxaline, 5 grams of 4-methylglyoxaline gave 7 grams of 5-nitro-4-methylglyoxaline (Found: N = 32'8. Calc.: N = 33d per cent.) melting at 248° (corr.), that is, 90 per cent, of the theoretical yield. 2-thiol-4-aminomethylglyoxa]ine. The low yield of 4-aminomethylglyoxaline recorded (56 per cent, of the theoretical) was due to the fact that insufficient ferric chloride had been employed. When the calculated quantity (16-2 grains) of this reagent is used, the product is obtained in a yield of 90 per cent, of the theoretical.