A. 6-Trityl-β-d-glucose-1,2,3,4-tetraacetate. A mixture containing 120 g. (0.67 mole) of anhydrous glucose, 193.2 g. (0.7 mole) of trityl chloride, and 500 ml. of anhydrous pyridine [Org. Syntheses Coll. Vol. 1, 100 (1941)], is heated on the steam cone until solution is complete (Note 1). Without cooling, 360 ml. of acetic anhydride is added in one portion (Note 2). After standing for 12 hours, the reaction mixture is poured slowly into 10 l. of ice water, to which 500 ml. of acetic acid has been added, and the resulting mixture is vigorously stirred mechanically for 2 hours (Note 3). The precipitate is filtered and is immediately stirred for a short time with 10 l. of ice water. The white, granular precipitate is filtered, washed well with cold water, and then air-dried (Note 4). The dried solid is digested with 500 ml. of ether (Note 5). The insoluble portion is dissolved in hot 95% ethanol (approximately 3 l.), and the solution is decolorized and filtered while hot. The filtrate, upon cooling, deposits fine needles of 6-trityl-β-d-glucose-1,2,3,4-tetraacetate of sufficient purity for further use. The yield at this point is about 169 g. (43%). Recrystallization from 95% ethanol gives the pure compound which melts at 166–166.5°. In pyridine, [α]¹⁹D is + 44.8°; [α]²⁸D, +45.3°. The yield of purified material is 137 g. (35%) (Note 6).

B. β-d-Glucose-1,2,3,4-tetraacetate. A solution of 46 g. (0.078 mole) of 6-trityl-β-d-glucose-1,2,3,4-tetraacetate in 200 ml. of acetic acid is prepared by warming on the steam bath. The solution is then cooled to approximately 10°, 18 ml. of a saturated solution of dry hydrogen bromide in acetic acid is added, and the reaction mixture is shaken for about 45 seconds. The trityl bromide formed during the reaction is removed at once by filtration, and the filtrate is poured immediately into 1 l. of cold water. The tetraacetate is extracted with 250 ml. of chloroform; the chloroform extract is washed four times with ice water and dried over anhydrous sodium sulfate. The drying agent is removed, and the chloroform is evaporated, under reduced pressure at room temperature. The remaining syrup is covered with 100 ml. of anhydrous ether and is rubbed with a glass rod. Crystallization takes place immediately. The product is removed and is purified by dissolving it in the minimum amount of chloroform and adding anhydrous ether until crystallization begins. The purified product melts at 128–129°. In chloroform, [α]²⁰D is +12.1°. The yield is 15 g. (55%).