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crystals, possessing about the same refractive index as the remaining 
mother-liquor, and, therefore, being almost invisible in it. 
Preparation of «-Chloro-tetracetyl-d- Fructose. 
30 Grams of freshly recrystallized and carefully dried (-letracetylfructose are 
dissolved in 90 ccm. dry chloroform in a glass bottle with ground stopper; the 
solution is cooled to 0° C. by means of ice. Now first 7,5 grams of finely powdered, 
dry Al,Cl, is added, and afterwards 19 grams of dry phosphoruspentachloride. 
When all is at 0° C., the vessel is removed from the ice bath, and the mixture 
is left at room-temperature for 30 minutes, while il is stirred from time to time 
and while an opportunity is given to the vapours of the hydrochloric acid formed 
and to those of the chloroform to escape. Then the bottle is placed once more 
into the ice, the contents of it, after being cooled rapidly, brought into a separating 
funnel, and the liquor rapidly washed with a solution of sodium-bicarbonate cooled 
with pieces of ice; finally it is again washed with some ice-water. The chloroform- 
solution is subsequently dried by means of coarsely grained anhydrous CaCl,, 
and the dry solution, after being filtered, rapidly evaporated in a wide crystallisa- 
tion-dish by means of a strong current of dry air, under a glass bell connected 
with drying apparatus. The very viscous mother-liquor gets finally crystallized; 
crusts of solid matter are deposited, which are put upon a hard filter, rapidly 
sucked-off, the crystals pressed between sheets of filterpaper, and dissolved in dry 
ether. In the ice-box colourless needles or thicker prisms were gradually deposited from 
the solution, which, if suited for measurements, must be investigated immediately. 
All necessary precautions being taken, the reaction yields about 60—65°/, of the 
theoretical quantity. 
Preparation of (-chloro-tetracetyl-d-fructose. The preparation of this isomeride 
occurs just in the same way as that of the a-derivative, only no xx 
Al,Cl, being added to the solution. After the chloroform has 
been evaporated, a small quantity of absolute alcoliol is added, 
by which immediately an aggregation of colourless needles is 
formed, which is treated as described above and then. repeat- 
edly recrystallized from boiling absolute alcohol. Measurable 
crystals are best obtained from benzene; the substance crystallizes 
in short, thick prisms, the a-isomeride (from ether) in more tiny, 
colourless needles. In both cases a yield of about the same 
percentage may be obtained. 
oe ee ee oe 
$ 3. a-Chloro-tetracetyl-d-fructose (mpt. 83°C.) 
crystallizes from dry ether at O° C. in the shape of 
small colourless and transparent needles, the end-faces 
of which are often only rudimentarily developed. 
They are rhombic, most probably bisphenoïdical, with 
the parameters: a: 6: c = 0,9759 :1:0,3284. 
Forms observed: a ={100}, narrow, but broader 
than 6 = {010}, which form generally is present only 
with a single, extremely narrow plane; m = ;110}, Fig. 1. 
large and lustrous, commonly yielding multiple reflexes; %-Chlorotetra- 
r= 101}, giving sharp mirror-images. In the zône acetyl-d-fructose. 
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