Angewandte
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Si-H units/g of polymer was mixed with 2 mL of acetone as solvent,
ozonized at À788C for 5 min and purged with argon to remove
residual ozone afterwards. Acetone was removed from the polymer
suspension with vacuum pump at À608C and replaced with diethyl
ether (2 mL) containing up to 0.1 vol.% of water (always present in
1
the reaction mixture under an experimental condition; for H NMR
spectra with added H2O and D2O see the Supporting Information)
and 0.03 mg (0.1 mmol) of MTO as a catalyst. Suspension was stirred
at À308C for 3 h to release hydrogen trioxide from the ozonized
dimethylphenylsilane-derivatized polymer bead 3 and filtered (at
À608C) to remove HOOOH solution (0.05m) from the polymer and
stored in refrigerator at À208C for weeks. The yield of released
HOOOH was 95–100%, based on the amount of starting polymer 2,
and calculated from 1H NMR spectrum of the calibrated residual
solvent peak for non-deuterated acetone and added 4-nitroacetophe-
none as an internal standard. Alternatively, the yield of HOOOH was
determined from the low-temperature oxidation (À408C) of stand-
ardized triphenylphosphine solution in diethyl ether, and produced
triphenyphosphin oxide calculated from GC-MS analyzes.[10] For
NMR experiments the solvent was removed in vacuo (À508C) and
replaced with [D6]acetone (1 mL), and transferred to the NMR tube
(for a typical NMR spectrum see Figure 2). For other experimental
work, the HOOOH solution was concentrated in vacuo (À508C) to
obtain a white glassy material, sufficiently stable at that temperature
to be dissolved in any other solvent.
1
Figure 4. A section of characteristic H NMR spectrum after HOOOH
addition to [D6]acetone (À508C).
of a polyoxide reacting with a carbonyl compound to form
a hydroxy-hydrotrioxide intermediate.[2c]
In summary, we have used low-temperature ozonation of
dimethylphenylsilane-derivatized polystyrene bead to pre-
pare a solid polymer (3) with directly attached hydrotrioxide
units. Furthermore, we have successfully released HOOOH
from polymer 3 into diethyl ether at À308C in a MTO-
catalyzed reaction in nearly quantitative yields. HOOOH
solutions in diethyl ether could be stored for weeks even at
temperatures as high as À208C. By evaporating the solvent,
HOOOH can be isolated in highly pure form, or it can be
dissolved in some other appropriate solvent, thus significantly
extending the possibilities of some novel HOOOH applica-
tions. The MTO-catalyzed addition of HOOOH to acetone to
form the hydroxy-hydrotrioxy intermediate is just one
example. The reactions of various organic compounds with
highly pure HOOOH as an oxidant are currently under
investigation.
WARNING: Although we have not had any accidents in handling
highly pure HOOOH, care should be exercised in handling of either
solid or concentrated solutions of this potentially hazardous com-
pound.
Acknowledgements
We are grateful for financial support from the Slovenian
Research Agency (ARRS) Junior Researcher Grant for G.S. ,
and the Program Grant P1–0230. We thank Professor J.
Plavec (Slovenian NMR Centre, National Institute of
Chemistry, Ljubljana) for the benefit from the NMR facility,
and Laboratory of Catalysis and Chemical Reaction Engi-
neering, National Institute of Chemistry, Ljubljana for low-
temperature ATR-IR measurements. We are also grateful for
COST Action no. CM0905 support.
Experimental Section
Instrumentation: Low-temperature 1H and 17O NMR spectra were
recorded on a Bruker Avance 300 DPX (1H NMR, 300.13 MHz; 17O
NMR, 40.70 MHz) and on Varian Unity Inova-600 spectrometers
(1H NMR, 600.09 MHz; 17O NMR, 81.37 MHz) with Me4Si and
[D6]acetone (1H NMR), and H217O (17O NMR) as internal standards.
ATR-IR spectra were recorded on a Bruker Alpha Platinum and
Applied Systems ReactIR 1000 spectrometers. GC-MS analyses were
Keywords: hydrogen trioxide · ozone · polystyrene beads ·
synthetic methods
performed on
column).
a Hewlett Packard 6890 instrument (HP-5 MS
Dimethylphenylsilane-derivatized polymer 2 was prepared by
following the procedure of Thomas and co-workers,[9] preparing
Oshimaꢀs complex (iPr(nBu)2MgLi, 2 equiv) in anhydrous THF
(60 mL) at 08C under an argon atmosphere. The solution of
iPr(nBu)2MgLi was stirred for 30 min to obtain a clear yellow
solution. 4-bromopolystyrene cross-linked with 2% divinylbenzene
(1, 1 equiv, 1.0 mmol Br loading/g of polymer, ABCR Chemicals) was
swollen in anhydrous THF (30 mL per gram of bead) for 15 min at
08C under an argon atmosphere and then the preformed iPr-
(nBu)2MgLi was added and the resultant mixture slowly stirred for
5 h keeping the temperature at 08C. Then chlorodimethylsilane
(6 equiv ABCR Chemicals, 98%) was added and the mixture was
agitated and allowed to warm to room temperature over 2 h.
Afterwards the derivatized polymer 2 was collected by filtration
and washed with stirring in DMF (at 508C, 30 min), water and
acetone, and dried under reduced pressure. Prepared polymer 2
contains roughly 1 mmol of Si-H units/g of polymer, as determined by
titration with standardized bromine solution.[14]
How to cite: Angew. Chem. Int. Ed. 2015, 54, 9917–9920
Angew. Chem. 2015, 127, 10055–10058
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b) “Peroxide Intermediates of Oxidation Processes: Organic
Trioxides”: S. Y. Khurshan in PATAIꢀs Chemistry of Functional
Groups, Vol. 3, Part 1 (Eds.: A. Greer, J. F. Liebman), Wiley-
VCH, Weinheim, 2014, pp. 125 – 195.
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Preparation of HOOOH: In a typical experiment, 100 mg of
dimethylphenylsilane-derivatized polystyrene 2 containing 1 mmol of
[3] a) B. Plesnicar, J. Cerkovnik, J. Koller, F. Kovac, J. Am. Chem.
Angew. Chem. Int. Ed. 2015, 54, 9917 –9920
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