A new property of geminal bishydroperoxides: Hydrolysis with the removal of hydroperoxide groups to form a ketone

Article abstract of DOI:10.1134/S1070363210080165

A new property of geminal bishydroperoxide was discovered: the ability to hydrolyze in acid medium in the presence of hydrogen peroxide with the formation of ketones. The most resistant to hydrolysis are the cyclic C ₆-bishydroperoxydes: at room temperature within one day they are practically not hydrolyzed; less stable is bishydroperoxycycloheptane (C ₇): in a day its one fifth part is hydrolyzed. Bishydroperoxydes with the cycles of C₈ and C₁₂ for the same time hydrolyzed to 80 and 90% respectively. Of the two linear bishydroperoxydes, 2,2-dihydroperoxydecane, with sterically unhindered center, is more resistant to hydrolysis than 6,6-dihydroperoxyundecane. Pleiades Publishing, Ltd., 2010.

Full text of DOI:10.1134/S1070363210080165

ISSN 1070-3632, Russian Journal of General Chemistry, 2010, Vol. 80, No. 8, pp. 1667–1671. © Pleiades Publishing, Ltd., 2010.
Original Russian Text © A.O. Terent’ev, O.B. Krivykh, I.B. Krylov, Yu.N. Ogibin, G.I. Nikishin, 2010, published in Zhurnal Obshchei Khimii, 2010, Vol. 80,
No. 8, pp. 1355–1359.
A New Property of Geminal Bishydroperoxides: Hydrolysis
with the Removal of Hydroperoxide Groups to Form a Ketone
A. O. Terent’ev, O. B. Krivykh, I. B. Krylov, Yu. N. Ogibin, and G. I. Nikishin
Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences,
Leninskii pr. 47, Moscow, 119991 Russia
e-mail: terentev@ioc.ac.ru
Received October 5, 2009
Abstract—A new property of geminal bishydroperoxide was discovered: the ability to hydrolyze in acid
medium in the presence of hydrogen peroxide with the formation of ketones. The most resistant to hydrolysis
are the cyclic C
less stable is bishydroperoxycycloheptane (C
with the cycles of C and C12 for the same time hydrolyzed to 80 and 90% respectively. Of the two linear
6
-bishydroperoxydes: at room temperature within one day they are practically not hydrolyzed;
7
): in a day its one fifth part is hydrolyzed. Bishydroperoxydes
8
bishydroperoxydes, 2,2-dihydroperoxydecane, with sterically unhindered center, is more resistant to hydrolysis
than 6,6-dihydroperoxyundecane.
DOI: 10.1134/S1070363210080165
In recent decades, a new wave of interest emerged
in the chemistry of organic peroxides, caused by the
discovery that these compounds have a high
malaricidal activity [1]. In the world this disease
affects about 500 million people [2]. The search for
peroxides with high antitumor [3] and antihelminthic
which makes it possible to use these compounds as
intermediates in the synthesis of peroxides of more
complex structure with malaricidal and antitumor
activity [7], as well as initiators of radical poly-
merization [8]. The high content of active oxygen
allows regarding them as promising oxidants [9].
[
4] activity is also promising. In industry, organic
Despite increased attention to the geminal bishyd-
roperoxydes, their thermal and hydrolytic stability
remain poorly studied. These characteristics are
necessary for a broader synthetic and practical use of
peroxides.
peroxides are traditionally used as oxidants and
initiators of radical polymerization [5].
Currently among the various classes of organic
peroxides geminal bishydroperoxydes (I) are
highlighted. Synthesis and application of such
compounds attracts the most attention. A half-century
ago, when the related peroxides obtained from ketones
have been known and used, the geminal bishydro-
peroxydes considered as unstable and hypothetical
compounds. More recently methods were developed
for the synthesis of such peroxides in preparative
amounts [6a–6k], based on the reaction of ketones and
aldehydes with H O catalyzed with I [6a], H SO [6b,
We discovered a previously unknown feature of the
geminal bishydroperoxydes: their ability to hydrolysis
with the loss of hydroperoxide groups, leading to the
formation of ketones. Analyzing the results of the
work on the synthesis of geminal bishydroperoxydes
by means of the reaction of ketones with aqueous
solution of hydrogen peroxide in THF [6b] and
alcohols [6c] catalyzed by sulfuric acid as well as the
research data of the iodine-catalyzed reaction of
ketones with aqueous solution of hydrogen peroxide in
acetonitrile [6a], we noted that the use of hydrogen
peroxide in the amount of 4–10 mol per 1 mol of
ketone, that is, much higher than the stoichiometric
2
2
2
2
4
6
c], Re O [6d], MeReO [6e], camphorsulfonic acid
2 7 3
(
CSA) [6f], F CCO H [6g], as well as on the reaction
3 2
of acetals and enol ethers with H O catalyzed by BF
2
2
3
[6h], H WO4 [6i] and phosphomolybdic acid,
2
H Mo O P·x H O [6j].
3
12 40
2
(
2 mol H O ), some ketones did not transform
2 2
A specific interest to this class of peroxides is due
to the presence in their molecule of two OOH groups,
completely into the target bishydroperoxydes. Perhaps
this is due to the existence of equilibrium with gem-
1
667

1
668
TERENT’EV et al.
a
The results of hydrolysis of gem-bishydroperoxyde (Ia–Ig)
Value geminal
Time of
Value geminal
bishydro–
Geminal bishydroperoxyde
bishydro–
peroxide I:
ketone II
Geminal bishydroperoxyde
Time of
hydrolysis,
h
(Ia–Ig)
(Ia–Ig)
hydrolysis, h
peroxide I:
ketone II
HOO
OOH
2
4
> 95:5
20
10:90
OOH
OOH
Ia
Ie
If
HOO
OOH
2
2
2
4
92:8
3.5
72:28
64:36
58:42
61:39
HOO
OOH
HOO
25
b
2
3
3
7
Ib
0
0
81:19
88:12
4
60:40
27:73
HOO
HOO
OOH
.5
25
OOH
Ig
Ic
2
20:80
OOH
Id
General conditions: To a mixture of bishydroperoxyde I (0.43–0.62 mmol, 100 mg), THF (6.6 ml/mmol of bishydroperoxyde), and 37%
aqueous solution of H (5 mol/mol of bishydroperoxyde) was added 3.5 M (28.7%) aqueous solution of H SO (0.5 mol/mol of
bishydroperoxyde). Stirred for 0.5–73 h at 20–25°C. To the decan-2-one (IIe), 76 mg (0.49 mmol), dissolved in 4 ml of THF was added
a
2
O
2
2
4
b
2 2 2 4
312 mg of 37% aqueous solution of H O (3.43 mmol, 7 mol/mol of decan-2-one) and 83 mg 29% aqueous H SO (0.25 mmol,
0
.5 mol/mol of decan-2-one).
bishydroperoxyde I and ketone II as the boundary
structures (Scheme 1).
acidified with sulfuric acid (see the table). Hydrogen
peroxide was used to simulate the conditions of
synthesis of geminal bishydroperoxyde I from ketones
II. Under these conditions (as already mentioned [6b,
Scheme 1.
6
c]) was not always possible to achieve high yields of
O
H O, H+
HOO
OOH
2
target bishydroperoxyde I, despite the excess of
hydrogen peroxide.
H O H+
2
2,
Ia−Ig
IIa−IIg
Based on the results of the experiments we can
conclude that the most resistant to hydrolysis are
bishydroperoxydes Ia, Ib with a six-membered ring,
which in a day at 20–25°C practically are not
hydrolyzed. The bishydroperoxycycloheptane Ic is less
In order to confirm this scheme, we synthesized a
series of geminal bishydroperoxydes with the ring size
C –C and C , as well as bishydroperoxydes from two
6
8
12
linear ketones, decan-2-one and undecan-6-one. These
bishydroperoxydes were hydrolyzed in the presence of
hydrogen peroxide in the THF–water solvent system
stable. Bishydroperoxydes with the rings C (Ig) and
8
C (Id) hydrolyzed to a much greater extent. Among
1
2
the geminal bishydroperoxydes obtained from linear
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 80 No. 8 2010

A NEW PROPERTY OF GEMINAL BISHYDROPEROXIDES
1669
ketones the more stable is peroxide Ic with sterically
less hindered reaction center. The geminal bis-
hydroperoxyde Ig hydrolyzed much more readily than
peroxide Ic. By an example of the peroxides Ic and Ig
it is seen that their hydrolysis is not a fast process, for
in 3.5–4 h the hydrolysis was not completed, the
equilibrium was established over 23–25 h only. The
synthesis of peroxide Ic was carried out using the
ketone IIf under the same conditions (see the table,
footnote b) as its hydrolysis. As a result, in 1 day the
equilibrium was reached with the content 58% of Ic
and 42% of IIf in the reaction mixture.
the geminal bishydroperoxyde lie in the region 8–
10 ppm (OOH), and for ketones at 2.1–2.4 ppm
(CH CO). Experiments on the hydrolysis of peroxides
2
Ia, Ib were performed with isolation of the products I
and II. The yields corresponded to the estimates
obtained by NMR spectroscopy without isolation of
the products.
Probably the hydrolysis of geminal bishydro-
peroxyde Ia–Ig proceeds along the following
mechanism. After the protonation (formation of the
intermediate A) and removal of hydrogen peroxide
hydroperoxycarbenium ion B is produced, which is
hydroxylated to form hydroxyhydroperoxyde C and,
after removal of the second hydrogen peroxide
molecule, it is transformed into ketone II (Scheme 2).
The molar ratio of hydrolysis products was
determined by comparing the intensity of the
1
characteristic signals in the H NMR spectra, which for
Scheme 2.
H
HOO + OOH
OOH
HOO
OOH
H+
− H O
2 2
+
H O H+
H O
2 2
2
2,
Ia−Ig
A
B
O
+
H O
2
HO
OOH
H+
−
H+
H O H+
2
2,
C
IIa−IIg
The kinetics of the acid-catalyzed hydrolysis of bis-
tert-butylperoxide (derivatives of linear ketones) with
similar structure, whose several homolog are produced
industrially and used to initiate polymerization, was
previously studied by spectrophotometry [10].
According to the kinetic measurements, the first rapid
phase of hydrolysis is the protonation followed by the
cleavage of tert-butylhydroperoxide and the formation
of peroxycarbenium cation, then follows the addition
of water and the cleavage of the second molecule of
tert-butylhydroperoxide.
OO–C–OO fragment [1i, 6a, 11]. In this investigation
these cross-reactions were suppressed by the use of
bishydroperoxyde I in low concentration and by
adding hydrogen peroxide to the reaction mixture.
Thus we found a new property of linear and cyclic
geminal bishydroperoxydes: the hydrolysis in acid
medium in the presence of H O resulting in the
2
2
formation of the corresponding ketones. The tendency
to hydrolysis of cyclic peroxides increases from 6-
membered to 8- and 12-membered ring; linear
peroxides C and C by the ability to hydrolysis are
1
0
12
In contrast to the bis-tert-butylperoxide, hydrolysis
of bishydroperoxyde I is more complex. It is
accompanied by the cross-reactions of peroxides I and
C with ketone II and cationic intermediate B with the
formation of products with bisperoxide fragment, (1,1'-
dihydroperoxyperoxides, 1,2,4,5- and 1,2,4,5-tetra-
oxanes, and 1,2,4,5,7,8-hexaoxanes), which were
identified in trace amounts by the signals at 105–
in an intermediate position between these two groups
of cyclic bishydroperoxydes.
The data obtained are important in predicting the
results of synthesis of peroxides from ketones in
aqueous solutions of hydrogen peroxide, and they
explain the unsuccessful attempts to obtain cyclic
peroxides from cyclic C –C and linear ketones with
8
15
1
3
sterically hindered reaction center in a high yield.
1
22 ppm in C NMR spectrum, characteristic of the
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 80 No. 8 2010

1
670
TERENT’EV et al.
EXPERIMENTAL
J 7.0 Hz), 1.23–1.47 m ( 12H, CH ), 1.62–1.78 m (4H,
2
CH ), 8.00–9.50 br.s (2H, OOH).
2
The NMR spectra were recorded on a Bruker AC-
00 and a Bruker AM-300 instruments (solvent
Hydrolysis of geminal bishydroperoxydes (Ia–
Ig). To a mixture of geminal bishydroperoxyde Ia–Ig
2
CDCl ). For the TLC were used Silufol UV-254 plates,
3
(
0.43–0.62 mmol, 100 mg), THF (6.6 ml per 1 mmol
for column chromatography, silica gel 63–200 mesh
Acros). Ketones IIa–IIf are the products of Acros.
of bishydroperoxyde) and 37% aqueous solution of
H O (5 mol per 1 mole of bishydroperoxyde) was
(
2
2
Tetrahydrofuran, Et O, CHCl3 (pure grade) and
2
added 3.5 M (28.7%) of the aqueous solution of H SO
2
4
petroleum ether (40–70) (pure grade) were distilled
before use. Geminal bishydroperoxydes Ia–Id, If are
known compounds, and peroxide Ic was obtained in
this study by the method [6h].
(
0.5 mol per 1 mol of bishydroperoxyde). After 0.5–
7
3 h, 30 ml of CHCl was added, the extract was
3
washed with 5 ml of a saturated solution of NaHCO3
and water (10 ml), dried over MgSO , the solvent was
removed in a vacuum of water-jet pump (8–15 mm Hg).
4
1
,1-Dihydroperoxy-4-tert-butylcyclohexane (Ia)
1
[
6b]. Colorless crystals, mp 81–82.5°C (Et O). The H
2
The ratio of geminal bishydroperoxyde Ia–Ig : ketone
1
NMR spectrum (250.13 MHz, δ, ppm): 0.85 s (9H,
IIa–IIf was measured by H NMR spectroscopy.
CH ), 0.98–1.78 m (7H, CH, CH ), 2.24–2.35 m (2H,
3
2
In experiments with bishydroperoxydes Ia, Ib the
separation of hydrolysis product I and II was carried
out using column chromatography with the gradient
elution with a mixture petroleum ether–Et O at
increasing the fraction of the latter from 5 to 20 vol %.
CH ), 9.25–9.40 br.s (2H, OOH).
2
1
,1-Dihydroperoxy-3,3,5-trimethylcyclohexane
1
(
Ib). Colorless crystals, mp 56–57.5°C (Et O). H
2
2
NMR spectrum (300 MHz, CDCl ), δ, ppm: 0.83–1.08
3
m (11H, CH , CH ), 1.22–1.47 m (2H, CH ), 1.73–
2
3
2
The reaction of the decan-2-one (IIe) with H O
2
2
1
2
.26 m (5H , CH, CH ), 9.45–9.55 br.s (2H, OOH).
2
2
(
see Table, footnote b). To decan-2-one IIe, 76 mg,
dissolved in 4 ml of THF was added 312 mg of 37%
aqueous solution of H O (3.43 mmol, 7 mol per 1 mol
3C NMR spectrum (75 MHz, CDCl ), δ, ppm: 22.0,
3
5.4, 26.3, 31.5, 33.6, 37.6, 40.6, 48.2 (CH, CH2,
CH ), 112.1 (C). Found, %: C, 57.03; H, 9.33.
2
2
3
of decan-2-one) and 83 mg of 29% aqueous H SO
C O H . Calculated, %: C, 56.82; H, 9.54.
2
4
1
8
9
4
(
0.25 mmol, 0.5 mol per 1 mol of decan-2-one). The
1
,1-Dihydroperoxycycloheptane (Ic) [6b]. Color-
reaction mixture was kept for 23 h, 30 ml of CHCl3
was added and the extract was washed with 5 ml of a
1
less crystals, mp 19–21°C (Et O). H NMR spectrum
2
(
1
300 MHz, CDCl ), δ, ppm: 1.28–1.65 m (8H, CH ),
3
2
saturated solution of NaHCO and water (10 ml), and
3
.70–2.03 m (4H, C–CH ), 9.60–9.80 br.s (2H, OOH).
2
dried over MgSO . The solvent was removed in a
4
1
vacuum of a water-jet pump (8–15 mm Hg). The ratio
1
,1-Dihydroperoxycyclooctane (Ig) [6b]. Oil. H
of geminal bishydroperoxyde Ic : ketone IIe was
NMR spectrum (300 MHz, CDCl ), δ, ppm: 1.21–1.99
3
1
determined by H NMR spectroscopy.
m (14H, CH ), 9.59–9.70 br.s (2H, OOH).
2
1
,1-Dihydroperoxycyclododecane
(Id)
[6b].
ACKNOWLEDGMENTS
1
Colorless crystals, mp 138–140°C (Et O). H NMR
2
spectrum (300 MHz, CDCl ), δ, ppm: 1.21–1.82 m
This work was supported financially by the
Program of support of leading scientific schools of
Russian Federation (VNSH 2942.2008.3).
3
(
22H, CH ), 9.98–10.04 br.s (2H, OOH).
2
1
2
,2-Dihydroperoxydecane (Ic). H NMR spectrum
(
1
300 MHz, CDCl ), δ, ppm: 0.88 t (3H, CH , J 6.6 Hz),
3
3
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2
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