Mendeleev
Communications
Mendeleev Commun., 2016, 26, 14–15
Alcoholysis of malonyl peroxides to give peracids
Margarita A. Lapitskaya, Vera A. Vil’, Elena D. Daeva, Alexander O. Terent’ev and Kasimir K. Pivnitsky*
N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 119991 Moscow, Russian Federation.
Fax: +7 499 135 8824; e-mail: kpiv@mail.ru
DOI: 10.1016/j.mencom.2016.01.006
Potassium acetate catalyzed alcoholysis of spirocycloalkyl malonyl peroxides affords 1-alkoxycarbonylcycloalkane-1-percarboxylic
acids which are suitable for epoxidation of olefins.
Cyclic diacylperoxides, malonyl peroxides (MPOs) in particular,
are promising reagents for heavy metal-free cis-dihydroxyla-
tion of olefins.1 Much earlier, MPOs were successfully used for
generation of low-stability a-lactones2 and malonic anhydrides,3
and recently for oxidative C–O coupling with 1,3-dicarbonyl
compounds.4
O
CO3H
CO2H
O
O
AlkOH, AcOK
25 °C, 15–30 min
CO2Alk
CO2Alk
O
2a–c
a Alk = Me
b Alk = Et
c Alk = Pri
3a–c
1
Little is known about other chemical properties of MPOs.
Slow solvolysis of dibutyl-MPO with methanol or ethanol at
22–80°C and 140°C gave dibutylmalonic acid, its monoesters
and products of their subsequent decarboxylation.5 Reaction
of spirocyclobutyl-MPO with sodium methoxide in methanol
afforded methyl hydrogen cyclobutane-1,1-dicarboxylate,6(a)
however, this transformation was explained as a fast reaction of
MPO with methanol.1(b) Dihydroxylation of olefins with MPOs
does not occur in methanol,1(b),(d) but the presence of 1 equiv. of
methanol does not interfere with this reaction in chloroform.1(f)
In terms of chemical structure, MPOs are mixed anhydrides
of a carboxylic and peroxy acids, hence MPOs can in principle
undergo alcoholysis to give esters (by the carboxyl group) of
substituted monopermalonic acids. We have found that the most
reactive MPO,1(a) spirocyclopropyl-MPO (1, Scheme 1), does
not react with 0.2 m solution of methanol in CDCl3 for 72 h
at 25°C, but is partially (by 20–30%) converted in methanol
solution, first to give peracid 2a along with other products. In the
course of reaction, unstable peracid 2a is gradually converted
into acid 3a, which is completed within 24 h. The methanolysis
of peroxide 1 is efficiently catalyzed by potassium acetate. In
the presence of 1 mol-equiv. AcOK in methanol, peroxide 1 is
converted nearly quantitatively to yield peracid 2a in 15 min.
Subsequent acidification of the reaction mixture to pH 1–6 some-
what stabilizes the peracid, however, peracid 2a can be isolated
only with an admixture of monoester 3a (71:29, respectively).†
Peracid 2a is more stable in a solution in CDCl3 wherein deoxy-
genation in 24 h at 4°C did not exceed 10%.
O
O
CO3H
CO2H
O
MeOH, AcOK
25 °C, 15 min
n
n
n
O
CO2Me
5a,b
CO2Me
6a,b
a n = 1
b n = 2
4a,b
Scheme 1
The reaction of peroxide 1 with ethanol catalyzed by AcOK
occurs similarly to produce homologous peracid 2b which was
isolated with much monoester 3b (45:55, respectively).† Although
the reaction of peroxide 1 with propan-2-ol under the same con-
ditions is completed in 30 min, the major product is a polymer
with unknown structure that is soluble in water but insoluble
(and nonrecoverable) in chloroform, so the isolated yield of the
mixture of peracid 2c and isopropyl monoester 3c (in 43:57
ratio) does not exceed 20%.† Active oxygen quickly disappears
in a solution of peroxide 1 and AcOK in tert-butanol.
This readily occurring alcoholysis of peroxide 1 is not due to
the presence of a cyclopropane moiety in its structure. Homo-
logous MPOs 4a,b with four- and five-membered rings equally
readily react with methanol on catalysis by AcOK to give peracids
5a,b, which were isolated with an admixture of monoesters 6a,b
(70:30 and 95:5, respectively).† Note that dibenzoyl peroxide
does not react in 24 h under these conditions.
The structure of peracids 2 and 5 obtained was confirmed by
spectral data‡ and by their complete conversion to the corre-
†
‡
1-Alkoxycarbonylcycloalkane-1-carboxylic peracids 2 and 5 (general
2a: 1H NMR (hereinafter, 300 MHz, CDCl3) d: 1.57–1.67 [m, AA'BB',
procedure). A solution of peroxide 1 or 4 and an equivalent amount of
anhydrous AcOK in an alcohol (5–15 ml mmol–1) was kept for 15 min
at 25°C (complete peroxide conversion according to TLC). The resulting
solution (in MeOH) or suspension (in EtOH or PriOH) with pH 7 was
acidified with CF3COOH to pH 1–2, diluted with water and extracted with
CHCl3. The extract was dried with MgSO4 and evaporated to dryness
in vacuo at 25°C to give almost quantitative yields (except in the reaction
with PriOH) of a mixture of peracids 2a,b and 5a,b with the corresponding
monoesters of cycloalkane-1,1-dicarboxylic acids 3a,b and 6a,b containing
no other components according to 1H NMR spectra. The compositions of
these mixtures are given in the text. They depend both on the peracid
structure and on the isolation conditions. The mixture of monomolecular
products obtained in 25–35% yields from 1 + PriOH contains ~2/3 (by
mass) 2c + 3c (in 43:57 ratio) and ~1/3 of other products.
4H, (CH2)2], 3.78 (s, 3H, OMe), 10.7 (br.s, 1H, OH). 13C NMR (herein-
after, 75 MHz, CDCl3) d: 17.7 [(CH2)2], 25.8 (C), 53.0 (OMe), 168.9
(CO3H), 170.7 (COO). Mass spectra could not be obtained for peracids 2
and 5, like for peroxides 1 and 4.1(a),(e)
2b: 1H NMR, d: 1.29 (t, 2H, Me, J 7.2 Hz), 1.56–1.67 [m, AA'BB', 4H,
(CH2)2], 4.23 (q, 2H, OCH2, J 7.2 Hz), 10.7 (br.s, 1H, OH). 13C NMR, d:
14.0 (OCH2Me), 17.7 [(CH2)2], 26.0 (C), 62.3 (OCH2Me), 168.6 (CO3H),
172.7 (COO).
2c: 1H NMR, d: 1.27 (d, 6H, 2Me, J 6.3 Hz), 1.54–1.65 [m, AA'BB',
4H, (CH2)2], 5.06 (sept, 1H, OCH, J 6.3 Hz), 7.9 (br.s, 1H, OH).
1
5a: H NMR, d: 2.07 (quint, 2H, CH2, J 8.1 Hz), 2.65 (t, 4H, 2CH2,
J 8.1 Hz), 3.79 (s, 3H, OMe), 10.2 (br.s, 1H, OH). 13C NMR, d: 16.6
[CH2(CH2)2], 29.2 [CH2(CH2)2], 50.6 [C(CH2)2], 53.2 (OMe), 170.7
(CO3H), 172.7 (COO).
© 2016 Mendeleev Communications. Published by ELSEVIER B.V.
on behalf of the N. D. Zelinsky Institute of Organic Chemistry of the
Russian Academy of Sciences.
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