:3. S o evidence that use of an optically active peroxide will cause an asymmetric synthe-
sis in vinyl polymerization has been obtained.
Trimolecular Acetone Peroxide in Isopropyl Ether
lot gave a viscous sirup from which no crystals of the trimolecular acetone peroxide were obtained. It is of interest to note that Radulesco5 found that the photochemical oxidation of isopropyl ether was slightly autocatalytic and produced acetone, water, peroxides, acids, and gum; and that Brown6 has shown the formation of acetone when the ether mixed with oxygen is passed over ii silver catalyst. Whether other peroxides are also present in isopropvl ether has not been determined. Trimolecular acetone peroxide is possibly responsible for the peroxide test found by Redemunn' with isopropanol.
131' FREDACRL'E, JR., AND
H.I,. HALLER
During the past few years several notes have appeared in the literature citing explosions of isopropyl ether.l I n all cases the ether had stood for several years and the explosion hazard was xttributed t o the formation of peroxides. So far :is we have been able to learn, the responsible iwroside has not been isolated or described. Recently, while an organic compound was beiiifi crystallized from isopropyl ether,2 the mother liquor was evaporated on the steam-bath with the aid of a stream of air t o about one-third of its original volume. On standing at room temperature, a crop of crystals, resembling common salt, separated. They melted at 94". On recrystallization from methyl alcohol the melting point was 9s'. The compound sublimed readily a t room temperature, liberated iodine from potassium iodide solution, and exploded on percussion or when heated on a platinum spatula. A molecular weight determination by the Signer method as modified by Clark3 gave a value of 221. The compound possessed all the properties of trimolecular acetone peroxide,' and a mixture melting point determination of the unknown peroxide with an authentic sample of trimolecular acetrme peroxide showed them t o be identical. ,. I rimolectilar acetone peroxide 'ivas readily obtained in crystalline form from four out of five lots of isopropyl ether, all of which gave qunlitative tests for peroxides, when the ether was evaporated t o one-third of its original volume on ithe steam-bath with a stream of air. The fifth .11 i a ) E. F. Degering, J . Chern. E d . , 13, 454 (1936); (b) B. 1.. Herrington, I n d . Eng. C'hem.. S e w s E d . . 20, 1458 (1942): ( c ) G . T organ and R. H. Pickard, Chem. and I n d . , 66, 421 (15:3tji, !d C. Williams, J . SOC.Chem. I n d . , 66, 580 (1938). (2) The ether was a commercial grade that had stood in the laboratory in clear glass bottles for at least tive years. I t was not purified before use. 3, E. P. Clark, I n d , E n s . C h e w . , A n d . Ed.. 13. 320 f 1941) 4 I< X-n!ffcmtriii. R V Y, 28, 22G5 '1895!
URBANA,
ILLINOIS
RECEIVED SEPTEMBER 3, 1942
( 5 ) G . Kadulesco, A n n . combusiible liquides, 13, 1071 (1938,. (6) R. L. Brown, U. S.Patent 2,246,569, June 24, 1941. t7) L'. E. Kedemann, THISJOURIVAL, 64, 3049 (1942).
I:.
S. DEPARTMENT OF AGRICULTURE :\GRICVI,rt'RAI, RESEARCH A1)MINISTRATIOK ~ PI,ANT Q U A R A N T I N E B U R E A U OF E N T O M 0 1 , O i ~ANI) RELTPVII.LE,M n . R E C E I V E D APRIL 14,
1943
Some Fluorinated Compounds of Possible Chemotherapeutical Interest 1 i Y I
