hydroperoxide
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Isopropyl Peroxide Synthesis
I have to say I am very intrigued with this peroxide.
[The following is excerpted from 'Reactions of Radicals. XI. Ethyl Peroxide, Isopropyl Peroxide, and sec-Butyl Peroxide'; by WILLIAM A. PRYOR, D. M.
HOSTON, . R. FISKE, . L. PICKERING and E. CIUFFARIN]
Preparation of Isopropyl Peroxide:
This peroxide has not been well characterized previously. Isopropyl methanesulfonate is conveniently prepared on a 3.5- mole scale in 80% yield. The
peroxide is then best prepared as follows. Isopropyl methanesulfonate (139.4 g. ) is placed in a 1-1. three-necked flask equipped with stirrer, reflux
condenser, and dropping funnel. The flask is heated to 51-52° and held there throughout the following preparation and distillation. A 20-ml. aliquot
of a solution of 52.6 g. of KOH diluted to 120 ml. with water is combined in the dropping funnel with a 12-ml. portion of 30%; hydrogen peroxide (both
solutions cooled to 0°). This mixture is added to the flask over 5 min. After 5 more min., 2 ml. more of hydrogen peroxide is added. After 5 more
min., the entire procedure is repeated. This addition cycle is repeated a total of six times. After the sixth cycle, the external stirrer is replaced
with a magnetic stirrer, and the dropping funnel is replaced with a simple distillation head with condenser and receiving flask (both held at 0°) and
a trap held at -78°. The reaction mixture is allowed to rapidly distill by reducing the pressure until 71 mm. is reached (flask still at 51°), at
which point the distillation is stopped. The distillate is extracted twice with hexane, and the combined organic phases are washed with three 15-ml.
portions of 5% aqueous KOH followed by three 15-ml. portions of water. The organic phase is then dried over sodium sulfate and distilled through a
4-in. column packed with Heli-Pack. The fraction boiling at 5.558° at 233 mm. is collected. In six preparations, yields varied from 16 to 26% and
averaged 20%.
Purity of Isopropyl Peroxide:
Several elemental analyzes gave average values of C, 60.32; H, 11.90, compared with calculated values of 60.97 and 11.94. However, elemental analysis
is hazardous and we no longer use it . Although neither we nor McMillan have been able to purposely detonate isopropyl peroxide at room
temperature by shock, we have experienced a violent explosion during an elemental analysis. The compound exploded while flowing through 3 quartz tube
at 200° in an oxygen stream, conditions which are known to detonate peroxides. Infrared and n.m.r. spectra are safe and entirely
satisfactory diagnostics of purity. The n.m.r. shows isopropyl groups with a doublet at 1.06 and 1.13 p.p.m. and a heptet centered at 4.1 p.p.m. with
an intensity ratio of 6: 1. Isopropyl hydroperoxide has a peak at 8.6 p.p.m. (the peak is shifted to 8.9 p.p.m. at 0°). The infrared spectrum shows
peak. at 3.4, 6.85, 7.3, 7.4, 7.6, 8.7 to 9.0 (broad), 10.85, and 12.2 μ . Acetone may be easily identified by its 5.8 μ peak and less than
0.2% is present. The sulfonate ha5 peaks at 8.4 and 9.4 p and less than 0.2yc is present. Isopropyl ether has a spectrum almost identical with that of
the peroxide, but has a strong peak at 9.9 μ which is absent in the peroxide. Isopropyl hydroperoxide has a peak at 2.9 μ . The
hydroperoxide is easily removed by washing with 5% potassium hydroxide and distillation.
According to the MSDS, 'isopropyl alcohol may react with oxygen in the air to form peroxides.' The question is could it be prepared with a much
simpler method by combining isopropyl alcohol and an oxidizer?!
[Edited on 19-2-2008 by hydroperoxide]
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PHILOU Zrealone
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I'm not sure about the stuff they are speaking about but, it seems to me that there is some confusion on the molecule
1°)
C3H8O2 ((CH3)2CH-O-O-H) isopropylperoxyde has a elemental analysis of:
C= 47.37%
H= 10.53%
O=42.10%
while the diisopropylperoxyde
C6H14O2 ((CH3)2CH-O-O-CH(CH3)2) has as elemental analysis:
C= 61.02%
H= 11.86%
O=27.12%
2°)
As a matter of facts isopropyl alcohol might in contact with H2O2 and under very specific circumstances form, after oxydation into propanone
(acetone), aceton peroxydes (mono-, cyclo di- and cyclo tri-). On its own isopropyl alcohol with O2 will not give much peroxydes!
3°)
On the other side diisopropyl ether in contact with air do easily form diisopropyl peroxyde and
Those 3 points goes in favor of a quo pro quo on the molecule.
*********************************************
*Thus Diisopropyl peroxyde and not isopropylperoxyde!*
*********************************************
[Edited on 20-2-2008 by PHILOU Zrealone]
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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Zinc
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http://www.sciencemadness.org/talk/viewthread.php?tid=845&am...
A thread about isopropyl peroxide.
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hydroperoxide
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I wonder if bubbling ozone through isopropyl alcohol would work. I would try myself if I wasnt so broke.
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