Preparation and properties of 1:4:5-trimethylglyoxaline / by Hooper Albert Dickinson Jowett.

  • Jowett, H. A. D. (Hooper Albert Dickinson)
Date:
[1905?]
Catalogue details

Licence: In copyright

Credit: Preparation and properties of 1:4:5-trimethylglyoxaline / by Hooper Albert Dickinson Jowett. Source: Wellcome Collection.

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    pure base was only 4 per cent, of the ketone taken. The base distilled at 165° under 10 mm. pressure and melted at 117°, this being the temperature given by Klinne. The nitrate, after* recrys¬ tallisation until the melting point was constant, formed colourless, acicular crystals which fused at 180° with effervescence. Kiinne gave the melting point as 164°. Dimethylglyoxaline yierate crystallises in brilliant yellow needles, which, after purification by recrystallisation from hot water and drying at 110°, melt at 196—197°. The picrates of the glyoxalines afford one of the easiest methods of identification of these bases, as they are readily formed, crystallise with facility, and have well defined melting points. Trimethylglyoxaline is best prepared by the action of sodium methyl- sulphate on the sodium derivative of dimethylglyoxaline, according to Titherley’s general method (Trans., 1901, 79, 401). In conducting this operation, it was found necessary, in order to obtain the best yield, to work with not more than 5 grams of glyoxaline at a time, and to expose as large a surface as possible of the mixed sodium salts to the action of heat. Even under the best conditions, the yield of trimethylglyoxaline was only 32 per cent, of the dimethylglyoxaline taken. The crude product, obtained by extracting the sodium salts with ether and removing the ether by distillation, was fractionated under 20 mm. pressure, when the greater portion distilled at 115—120°, a little unchanged dimethylglyoxaline being recovered from the higher fractions. On redistillation, the greater portion boiled at 117° under 20 mm. pressure and solidified in the receiver to a mass of long, acicular crystals. These were drained on porous earthenware and then dried in a vacuum over sulphuric acid. The crystals melt at 46° and are soluble in all proportions in water, alcohol, or ether. On exposure to the air for only a few seconds they absorb moisture and liquefy. 0-1386 gave 0*3340 C02 ami 0*1132 H20. 0 = 65*7; H = 9*l. 0 0972 ,, 21*6 c.c. nitrogen at 18° and 761 mm. N = 25*2. C6H10N2 requires C = 65*5 ; H = 9*1 ; N = 25*4 per cent. The base has the characteristic odour of the glyoxalines previously described. Attempts to prepare the base by the action of dimethyl sulphate on dimethylglyoxaline were unsuccessful. Trimethylglyoxaline nitrate, C6H10N2,HNO3,H2O, separates from its aqueous solution in long, acicular crystals which, after purification by recrystallisation, melt at 46°. It is readily soluble in water or alcohol, but insoluble in ether. When crystallised from alcoholic solution by the addition of ether, the crystals melt indefinitely at