Catalytic oxidation of α-alkenes with hydrogen peroxide to carboxylic acids in the presence of peroxopolyoxotungstate complexes

Article abstract of DOI:10.1016/j.catcom.2016.09.019

Fine organic synthesis investigation has been performed, focusing on the possibility of efficient oxidation of α-alkenes by hydrogen peroxide under conditions of phase transfer catalysis using bifunctional metal complex catalysts based on peroxotungsten compounds of general formula Q₃{PO₄[WO(O₂)₂]₄}, where Q is organic cation containing quaternary nitrogen atom. Catalysts screening has been done at oxidation of octene-1, decene-1 and dodecene-1 by 30% aqueous hydrogen peroxide to obtain carboxylic acids: heptanoic, nonanoic and undecanoic acids being of importance since used as precursors in the synthesis of various organic and biologically active compounds. This approach to the synthesis of carboxylic acids may be of interest for the processes of “green chemistry” occurring under mild conditions (Т?

Full text of DOI:10.1016/j.catcom.2016.09.019

Catalysis Communications 88 (2017) 45–49
Contents lists available at ScienceDirect
Catalysis Communications
journal homepage: www.elsevier.com/locate/catcom
Short communication
Catalytic oxidation of α-alkenes with hydrogen peroxide to carboxylic
☆
acids in the presence of peroxopolyoxotungstate complexes
⁎
Z.P. Pai , N.V. Selivanova, P.V. Oleneva, P.V. Berdnikova, A.M. Beskopyl'nyi
Boreskov Institute of Catalysis, Department of Catalytic Processes of Fine Chemical Synthesis, Akad. Lavrentiev Pr. 5, Novosibirsk 630090, Russia
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 20 July 2016
Received in revised form 29 August 2016
Accepted 14 September 2016
Available online 15 September 2016
Fine organic synthesis investigation has been performed, focusing on the possibility of efficient oxidation of α-al-
kenes by hydrogen peroxide under conditions of phase transfer catalysis using bifunctional metal complex cata-
lysts based on peroxotungsten compounds of general formula Q3{PO4[WO(O2)2]4}, where Q is organic cation
containing quaternary nitrogen atom.
Catalysts screening has been done at oxidation of octene-1, decene-1 and dodecene-1 by 30% aqueous hydrogen
peroxide to obtain carboxylic acids: heptanoic, nonanoic and undecanoic acids being of importance since used
as precursors in the synthesis of various organic and biologically active compounds. This approach to the synthe-
sis of carboxylic acids may be of interest for the processes of “green chemistry” occurring under mild conditions
(Т b 100 °С, Р – atm) in one stage without organic solvents, and providing high target product yields (86–97%).
© 2016 Elsevier B.V. All rights reserved.
Keywords:
Phase-transfer catalysis
Alpha-alkenes
Carboxylic acids
Peroxotungstate complexes
Quaternary ammonium cations
1. Introduction
saturated fatty acids are known to possess antibiotic and antifungi activ-
ities [9].
Carboxylic acids С7, С9 and С11 as well as their derivatives are widely
used in various fields such as large scale chemistry, oil chemistry, agro
chemistry and food and perfumery industries [1–3]. Thus heptanoic
(enanthic) acid is applied in the synthesis of hydraulic liquids and lubri-
cants [4]. Nonanoic (pelargonic) acid is used in production of polyester
alkyd resins and synthetic oils, plasticizing agents, dyes, stabilizers as
well as in the biosynthesis of polyoxyalcanoates (biodegradable poly-
mers for medicine) [1,3–5]. Undecanoic (undecylic) acid is applied in
production of surfactants and emulsifiers.
Esters of above mentioned acids are popular as aromatic substrates
and taste additives and are actively applied in fine organic synthesis
for modification of complex medical preparations [4–6]. Pelargonic
acid esters enter biodiesel fuel compositions [7]. Corresponding acid
salts, i.e. enanthoates, pelargonates, undecanoates, are also demanded.
For example, ammonium pelargonate is used as herbicide and blossom
regulator in agriculture. Calcium enanthoate enters testosterone prepa-
rations used for healing anemia, trachoma and eye diseases [8]. All
For a long time aliphatic carboxylic acids were obtained from the
plant raw materials. At first, nonanoic and azelaic acids were obtained
via oleic acid oxidation by concentrated (N80%) nitric acid in the pres-
ence of vanadium compounds [10]. Since that time many methods
were suggested for carboxylic acid synthesis improvement such as oxi-
dizer (nitric acid) concentration decrease, process temperature and
pressure increase; oxidative decomposition of unsaturated fatty acids
of natural origin; application of novel catalysts, allowing process perfor-
mance under milder conditions [11]; oxidation performance by strong
mineral acids combined with other oxidizers such as hydrogen peroxide
[12,13]. In 70-s carboxylation was intensively studied as a method for
alkenes processing into carboxylic acids via carbon monoxide and
water molecules addition along the alkene double bond. This method
provided best results, when assisted by Rh and Pd phosphine complexes
[14]. However, in this case carboxylation was performed under rather
severe conditions such as pressure up to 8 МPa and temperature up to
200 °С.
Some industrial processes are based on alkenes hydrocarboxylation
at 90–120 °С and under elevated CO pressure (up to 125 atm) in the
presence of Ni or Co carbonyls based catalysts such as pyridine modified
Со(СО)8 in organic solvent [15]. Aliphatic carboxylic acids are also pro-
duced via alkanes oxidation by air oxygen or ozone-oxygen mixture in
the presence of manganese salts at 105–120 °С [16,17]. However, all
above described technologies have disadvantages: low yields of target
acids (b50%), poor product purity, large amounts of waste waters (up
to 8 м3 per 1 ton of product) polluted by Na2SO4 and low molecular
☆
Various α-alkenes (С8, С10 and С12) were oxidized in a two-phase liquid system by a
30% solution of hydrogen peroxide in the presence of metal complex catalysts
Q3{PO4[WO(O2)2]4}, Q being organic cation: [Bun4N]+, [MeOctn3N]+, [C5H5NCetn]+
.
Carboxylic acids (heptanoic, nonanoic and undecanoic) were found to form with high
yields (97, 90 and 86% respectively) at temperatures below 100 °С under atmospheric
pressure in one stage, no organic solvents being used. This approach towards carboxylic
acids synthesis may be of interest for “green chemistry” processes.
⁎
Corresponding author.
E-mail address: zpai@catalysis.ru (Z.P. Pai).
http://dx.doi.org/10.1016/j.catcom.2016.09.019
1566-7367/© 2016 Elsevier B.V. All rights reserved.

46
Z.P. Pai et al. / Catalysis Communications 88 (2017) 45–49
weight acids. Therefore, more feasible and environment friendly tech-
nologies for carboxylic acids synthesis are still required.
300 °C (10 min), carrier gas – He with linear velocity of 50 cm/s (GC con-
ditions); determined m/z 35–500, detector voltage 0.9 kV, emission cur-
rent 60 μA, ion source temperature 250 °С (MS conditions).
In the present study we focus on new approaches to the synthesis of
aliphatic monocarboxylic acids to be used for the up to date ways of
their production. For the purpose α-alkenes (octene-1, decene-1,
dodecene-1) are oxidized by hydrogen peroxide in a two phase system
using bifunctional catalysts based on oxoperoxotungstate complexes
Q3{PO4[WO(O2)2]4}, where Q is quaternary ammonium cation [18–
21]. The anion {PO4[WO(O2)2]4}3− (Scheme 1) is a tetra nuclear
peroxopolyoxotungstate known as Venturello complex [18]. It has
the C2 symmetry and consists of the central PO4 tetrahedron linked
through its oxygen atoms to two pairs of edge-sharing distorted
pentagonal bipyramids W(O2)2O3. Each tungsten atom is linked to
two peroxo groups – one nonbridging (η2-O2) and the other bridging
(μ-η1:η2-O2) – located in the equatorial plane of the pentagonal
bipyramid. The oxidizing moiety is the η2-peroxo group.
2.3. Synthesis of the catalytic complexes
Catalysts Q3{PO4[WO(O2)2]4} were synthesized according to proce-
dures [23,24], which describe synthesis of tungstate tetra nuclear
peroxopolyoxo complexes with using tungstophosphoric heteropoly
acid of Keggin-type and 30%-H2O2 as precursors. It has previously
been established [24], that bi- and tetra-nuclear tungsten peroxo com-
plexes are formed during the synthesis as a result of a number of reac-
tions, which can be represented by the following summary equation:
È
Â
à É
H3PW12O40 þ 24H2O2 þ 3QCl→Q3 PO4 WOðO2Þ2
↓þ
4
Â
Ã
þ 4H2 W2O3ðO2Þ4 þ 3HCl þ 20H2O
Above mentioned α-alkenes are chosen as substrates, as being inex-
pensive large scale oil chemistry products obtained at high temperature
ethylene oligomerization [22].
Physical and chemical properties of obtained tetra nuclear com-
plexes of tungsten are similar to those described in [23,24].
Catalytic complexes: I – [Bun4N]3{PO4[WO(O2)2]4}, colourless
crystals, m.p. = 128–129 °C (lit. m.p. = 127–130 °C [23]); III –
[C5H5NCetn]3{PO4[WO(O2)2]4} – colourless crystals, m.p. = 130 °C (lit.
m.p. = 130–131 °C [23]); II – [MeOctn3N]3{PO4[WO(O2)2]4}, yellowish
syrup-like substance, 1Н NMR (300 MHz, C6D6), δ (ppm): 4.29 (s, 1H),
3.20 (m, 5H), 2.94 (m, 10H), 1.39 (m, 78H), 1.03 (m, 20H), 0.29
(s, 2H); 31P NMR (121.49 MHz, C6D6), δ (ppm): 4.41 (m). IR spectra
of complexes I–III correspond to anion {PO4[WO(O2)2]4}3− and
consistent with our results [23,24b] and the published data [18,
19]: I – [Bun4N]3{PO4[WO(O2)2]4} – (P-O)as 1084, 1063, 1034;
(W = O)as 972; (O-O) 853, 845; (W-O-O)s 650; (W-O-O)as 590,
574, 548, 521 cm−1; II – [MeOctn3N]3{PO4[WO(O2)2]4} – (P-O)as
1088, 1057, 1032; (W = O)as 976; (O-O) 856, 846; (W-O-O)s 652;
(W-O-O)as 591, 577, 549, 523 cm−1; III – [C5H5NCetn]{PO4[WO(O2)2]4}
– (P-O)as 1090, 1060, 1033; (W = O)as 985, 960; (O-O) 855, 844;
2. Experimental
2.1. Materials
Commercially available octene-1 («Acros Organics», 99 + %),
decene-1 («Acros Organics», 95%), dodecene-1 («Acros Organics», 93–
95%), hydrogen peroxide (30–33% water solution) («Khimreaktiv», spe-
cial purity grade), 1,2-dichloroethane («Khimreaktiv», chemical purity
grade) were used without preliminary purification.
Keggin-type 12-tungstophosphoric heteropoly acid – H3PW12O40
×
6H2O («Acros Organics») and quaternary ammonium salts: [Bun4N]Cl
(«Fluka Chemie», N98%), [MeOctn3N]Cl (Aliquat®336, «Acros Organics»),
[C5H5NCetn]Cl («Acros Organics») were used for catalysts' synthesis.
2.2. Analytic methods
(W-O-O)s 649; (W-O-O)as 590, 572, 548, 523 cm−1
.
GC analysis of products of α-alkenes catalytic oxidation (octene-1,
decene-1, dodecene-1) was performed with gas chromatograph
“Khromos-1000” (Russia), equipped with flame ionization detector
and capillary column SolGel-Wax 30 m × 0.53 mm «SGE». Reaction mix-
ture analysis was performed in isothermal regime Тcol = 220 °С, detec-
tor temperature was 300 °С, evaporator temperature was 230 °С, carrier
gas – He. Analysis duration was about 50 min. Absolute calibration was
used to determine the quantitative product amount.
GCMS analysis of organic phase was performed with GCMS-QP2010
Ultra Gas chromatography mass spectrometer. Analysis conditions
were: injection port temperature 250 °C, capillary column GsBP1-MS
30 m × 0.32 mm, programmed heating: 50 °C (7.5 min) – 20 °C/min –
Samples IR spectra were recorded with IR Fourier spectrometer
IRAffinity-1 Shimadzu within 400–4000 cm−1 resolution being 4
cm−1, scans number being 50. Samples were arranged as tablets with
KCl (samples of catalysts I, III) or in the form of a film (sample of catalyst
II). For tablets preparation 3 mg of compound were mixed with 300 mg
of dewatered KCl then carefully ground in agate mortar and pressed.
Samples were weighted using Leki Electronic Balance B2104.
1H and 31P NMR spectra were recorded at a Bruker AV-300 spec-
trometer in C6D6 (300.13 MHz for 1H, 121.49 MHz for 31P) for solution.
Proton chemical shifts were recorded relative to tetramethylsilane ex-
ternal standard. The 31P NMR spectra were recorded using H3PO4
(0 ppm) as an external standard.
3-
2.4. Organic substrate oxidation procedure
α-Alkenes were oxidized in a thermostat glass reactor (volume
180 ml), equipped with reflux condenser and magnetic stirrer (n =
500 min−1). Temperature 60–95 °С was maintained with water ther-
mostat with an accuracy of 0.1 °С. For reaction mixture preparation
weighted catalyst sample was put into reactor, then, substrate was
added and mixed with catalyst. After that 30% aqueous hydrogen perox-
ide was introduced, and heating was started. Catalysts II and III well dis-
solved in the substrate. Catalyst I was preliminarily dissolved in a small
amount of 1,2-dichloroethane (1–2 ml).
2−O2
μ−η1 η2
η
:
−O2
Reaction mixture was sampled in definite time intervals. For the
purpose stirring was stopped. After organic and aqueous phases com-
plete separation into layers (no longer than 20–30 s) sample from or-
ganic phase was taken. Carboxylic acid yield was determined using
chromatography analysis via absolute calibration.
W
O
Scheme 1. Structure of tetra nuclear peroxopolyoxotungstate {PO4[WO(O2)2]4}3−
.

Z.P. Pai et al. / Catalysis Communications 88 (2017) 45–49
47
n
n
m
2
2 m
2
3
2 2 4
(active form)
3
4
2 2 3
(inactive form)
2
Q+: [Bun4N]+, [MeOctn3N]+, [C5H5NCetn]+
Organic phase
Aqueous phase
H2O2
2
Scheme 2. Scheme of α-alkenes oxidation by hydrogen peroxide in the two-phase system water phase – organic phase in the presence of peroxopolyoxotungstate complexes.
3. Results and discussion
data also confirm results obtained earlier at cycloalkenes [26,27]
and fatty acids [28] oxidation by hydrogen peroxide.
Oxidation of α-alkenes by hydrogen peroxide in the presence of cat-
alysts I, II and III at 60–95 °С under atmospheric pressure yields aliphat-
ic carboxylic acids with carbon atoms number less by 1 than that in
initial alkene (Scheme 2).
Despite the fact that complex III has shown the highest activity in
oxidation of α-alkenes, for further investigation we have chosen com-
plex II, as showing higher stability with time [23].
3.2. Temperature effect on the yield of carboxylic acids
3.1. Screening of catalysts
Temperature effect on the yield of carboxylic acids was studied in a
range of 60–95 °С. According to the data obtained (Fig. 2), yields of de-
sired acids grow with temperature, and attain maximum at tempera-
tures close to 100 °С. Further temperature increase is limited by the
water phase boiling point. Therefore, it is necessary to elevate pressure
for higher yields of acids.
Screening of catalytic complexes I, II and III in oxidation of α-al-
kenes С8, С10 and С12 was done at 80 °С. Ratio [Ox]/[Sub] = 5 was cho-
sen in accordance with reaction stoichiometry (1 mol of substrate/5 mol
of oxidizer).
The highest yields of heptanoic, nonanoic and undecanoic acids
(Fig. 1) were obtained over catalytic complexes II and III, carboxylic
acid yields over complex I were lower. This means that lipophilic
properties of phase transfer catalyst has essential effect on its
distribution between organic and water phases. Activity series
[C5H5NCetn]3{PO4[WO(O2)2]4} N [MeOctn3N]3{PO4[WO(O2)2]4} N
[Bun4N]3{PO4[WO(O2)2]4} is in a good agreement with that of extrac-
tion constant logarithms experimentally determined for quaternary
salts of bromine in system water – organic solvent [25]. Activity
3.3. Influence of catalyst and oxidizer concentrations on carboxylic acid
yield
Oxidation of octene-1 was used to study the influence of oxidizer
(Fig. 3) and catalyst II concentrations (Table 1) on the carboxylic acid
yield. Heptanoic acid yield versus substrate/catalyst ratio curve shows
that [H2O2]/[Sub] = 5 is optimum, which corresponds to reaction
100
90
80
70
60
50
40
30
20
10
0
100
1
95
2
90
3
85
80
75
70
65
60
55
50
1
2
3
1 - C H COOH, 2 - C H COOH, 3 - C H COOH
55
60
65
70
75
80
85
90
95
100
6
13
8
17
10 21
T, ˚C
Fig. 1. Diagrams of carboxylic acid yields depending on catalyst type, ([Sub]/[Cat] = 250,
[H2O2]/[Sub] = 5, Тreaction = 80 °С, τreaction = 5 h).
– [Bun4N]3{PO4[WO(O2)2]4} (I);
– [MeOctn3N]3{PO4[WO(O2)2]4} (II); – [C5H5NCetn]3{PO4[WO(O2)2]4} (III).
Fig. 2. Carboxylic acid yield versus reaction temperature (catalyst II, [Sub]/[Cat] = 250,
[Ox]/[Sub] = 5, τreaction = 5 h) 1 – C6H13COOH, 2 – C8H17COOH, 3 – C10H21COOH.

48
Z.P. Pai et al. / Catalysis Communications 88 (2017) 45–49
Table 1
26
24
22
20
18
16
14
12
10
8
Heptanoic acid yield versus catalyst concentration in reaction mixture (Sub – 1-C8H16
[H2O2]/[Sub] = 5, Тreaction = 90 °С, τreaction = 90 min).
,
No
[Cat] × 103
M
[Sub]/[Cat]
Yield C6H13COOH, mol. %
1
2
3
4
5
6
63.6
42.4
25.4
12.7
8.47
3.63
100
150
250
500
750
1000
44.9
39.3
25.1
12.3
10.0
0.10
Cat – [MeOctn3N]3{PO4[WO(O2)2]4} (II).
the substrate. The subsequent regeneration of the peroxo complex
with hydrogen peroxide occurs at the interfacial surface (Scheme 2).
6
0
2
4
6
8
10
[H O ] / [Sub]
2
4. Conclusions
2
Our investigation focused on oxidation of several α-alkenes (octene-
1, decene-1, dodecene-1) by 30% aqueous hydrogen peroxide in the two
phase system using metal complex bifunctional catalysts based on
oxoperoxotungsten complexes Q3{PO4[WO(O2)2]4}, containing organic
cation (Q) have shown that:
Fig. 3. Heptanoic acid yield versus molar ratio [H2O2]/[Sub] (catalyst II, Sub – 1-C8H16, Ox –
30% aqueous H2O2, [Sub]/[Cat] = 250, Тreaction = 80 °С, τreaction = 90 min).
stoichiometry. This fact indirectly confirms that hydrogen peroxide de-
composition does not occur under reaction conditions, or that its contri-
bution is negligible. Therefore, such process may proceed in the
minimum excess of oxidizer (about 10–12% from theoretical one).
According to Table 1 essentially high catalyst concentrations are
needed for octene-1 oxidation to heptanoic acid, when [Sub]/
[Cat] ≤ 250. At the same time molar ratio [Sub]/[Cat] ≥ 1000 is required
when unsaturated fatty acids and their methyl esters are oxidized to
produce epoxides or when their double bond С_С is cleaved at oxida-
tion [28]. When alcohols or cycloalkenes are oxidized to mono- and di-
carboxylic acids [23] required ratio [Sub]/[Cat] ranges from 500 to 100.
The latter data are in good agreement with results obtained in our
experiments.
- corresponding carboxylic acids such as heptanoic, nonanoic and
undecanoic acids form with high yields 97, 90, 86%, respectively, at
temperatures b100 °С under atmospheric pressure in one stage, no
organic solvents being required;
- tested complexes [C5H5NCetn]3{PO4[WO(O2)2]4} and [MeOct-
n
3N]3{PO4[WO(O2)2]4} have comparable activities, when catalyze
oxidation of above mentioned α-alkenes;
- oxidizer amount required for reaction performance is close to stoi-
chiometry and its excess should not exceed 10–12%;
- in order to provide higher target product yields it is necessary to pro-
vide catalyst concentration at which 50 ≤ [Sub]/[Cat] ≤ 250.
3.4. Intermediate and side reaction products
Therefore presented method of carboxylic acids synthesis may be of
interest as a “green chemistry” process performed in one stage at low
temperatures and atmospheric pressure. Regarding all above men-
tioned and accounting for obvious practical perspectives [29], we plan
further detailed investigation of reaction optimization and detailed rev-
elation of its mechanism.
Analyzing data given on Fig. 4, one may see carboxylic acid yield ver-
sus time curves being S-shaped. Let us note that as temperature de-
creases, induction period increases. Induction period may signify that,
first, carboxylic acids (C6H13COOH, C8H17COOH, C10H21COOH) form
via a complex mechanism. Second, some intermediate products are
forming and accumulating, thus limiting carboxylic acids formation in
whole. Separate experiments with octene-1 oxidation to determine of
intermediates were performed at 60 °С using chromatography plus
mass spectrometry1 for reaction mixture analysis. It has been shown
that 1,2-epoxyoctane, 1,2-octanediol and heptanal as well as two
more not yet identified compounds (in quantities not larger than
1.0%) are present beside substrate (octene-1) and product (heptanoic
acid). Attempts to isolate these components from the reaction mixture
for characterization by NMR, were unsuccessful.
Thus, based on these results, it can be confirmed that the reaction in-
cludes the step of forming the intermediate epoxide (limiting stage),
which is most likely exposed to acid hydrolysis to form a diol. Further
oxidation leads to the cleavage of C\\C bond of the diol to form of the
desired product – heptanoic acid as well as three byproducts including
heptanal.
100
1
2
90
3
80
70
60
50
40
30
20
10
0
On the whole, the oxidation reaction of α-alkenes by hydrogen per-
oxide under the phase-transfer catalysis occurs in the organic phase
(the role of organic phase performs a substrate) via the transport of ox-
ygen atom from the tetra(oxodiperoxotungstato)phosophate (3−) to
0
30
60
90 120 150 180 210 240 270 300 330 360
t, min
1
Authors express gratitude to senior researcher Prikhod'ko S.A. for mass spectrometry
Fig. 4. Carboxylic acid yield versus reaction time (catalyst II, [H2O2]/[Sub] = 6, [Sub]/
[Cat] = 200, Т = 90 °С) 1 – C6H13COOH, 2 – C8H17COOH, 3 – C10H21COOH.
analysis and data interpreting.

Z.P. Pai et al. / Catalysis Communications 88 (2017) 45–49
49
[15] S.N. Lakeev, S.G. Karchevskiy, I.O. Maidanova, V.I. Aleksashev, Sbornik materialov
mezhregional'nojj nauchno-prakticheskojj konferencii Innovacionnye processy v
oblasti obrazovanija, nauki i proizvodstva, g, Rossija, Nizhnekamsk, 2004.
[16] S.D. Razumovskii, G.E. Zaikov, Russ. Chem. Rev. 49 (1980) 1163–1180.
[17] I.Z. Gljanc, V.V. Beresnev, A.A. Petukhov, V.V. Klochkov, Zhurnal prikladnojj khimii
66 (1993) 1179–1182.
[18] a) C. Venturello, M. Gambaro, J. Org. Chem. 56 (1991) 5924–5931;
b) C. Venturello, R. D'Aloisio, J.C.J. Bart, M. Ricci, J. Mol. Catal. 32 (1985) 107.
[19] Y. Ishii, K. Yamawaki, T. Ura, H. Yamada, T. Yoshida, M. Ogawa, J. Org. Chem. 53
(1988) 3587–3593.
Acknowledgements
This work was supported by RFBR (project 16-03-00127а); Russian
Academy of Sciences and Federal Agency of Scientific Organizations
(project V.44.2.8).
References
[20] W. Zhao, B. Ma, H. Hua, Y. Zhang, Y. Ding, Catal. Commun. 9 (2008) 2455–2459.
[21] J. Xue, A. Wang, H. Yin, J. Wang, D. Zhang, W. Chen, L. Yu, T. Jiang, J. Ind. Eng. Chem.
16 (2010) 288–292.
[22] E.U. Isakov, Neftepererabotka i Neftekhimija 3 (2013) 30–33.
[23] Z.P. Pai, A.G. Tolstikov, P.V. Berdnikova, G.N. Kustova, T.B. Khlebnikova, N.V.
Selivanova, A.B. Shangina, V.G. Kostrovskii, Russ. Chem. Bull. 54 (2005) 1847–1854.
[24] a) Z.P. Pai, D.I. Kochubey, P.V. Berdnikova, V.V. Kanazhevskiy, I.Y. Prikhod'ko, Y.A.
Chesalov, J. Mol. Catal. A Chem. 332 (2010) 122–127;
[1] M.F. Doherty, J.P. Knapp, Carboxylic Acids in Kirk-Othmer Encyclopedia of Chemical
Technology, fifth ed. John Wiley, New Jersey, 2004 786–852.
[2] J. Kubitschke, H. Lange, H. Strutz, Carboxylic acids, aliphatic, Ullmann's Encyclopedia
of Industrial Chemistry, Wiley-VCH, Weinheim, 2014, http://dx.doi.org/10.1002/
14356007.a05_235.pub2.
[3] W. Riemenschneider, Carboxylic acids, aliphatic, Ullmann's Encyclopedia of Indus-
trial Chemistry, Wiley-VCH, Weinheim, 2000, http://dx.doi.org/10.1002/14356007.
a05_235.
[4] S.E. Turnwald, M.A. Lorier, J. Mater. Sci. Lett. 17 (1998) 1305–1307.
[5] A. Clemmensen, K.E. Andersen, O. Clemmensen, Q. Tan, T.A. Kruse, M. Tomassen, T.K.
Petersen, J. Invest. Dermatol. 130 (2010) 2201–2210.
[6] G.A. Burdock, Fenaroli's Handbook of Flavor Ingredients, fifth ed. CRC Press, 2004.
[7] F. Jin, X. Zeng, J. Cao, K. Kawasaki, A. Kishita, K. Tohji, H. Enomoto, Fuel 89 (2010)
2448–2454.
b) D.I. Kochubey, P.V. Berdnikova, Z.P. Pai, Y.A. Chesalov, V.V. Kanazhevskiy, T.B.
Khlebnikova, J. Mol. Catal. A Chem. 366 (2013) 341–346.
[25] E.V. Dehmlov, S.S. Dehmlov, Phase Transfer Catalysis, third ed. VCH, Weinheim,
1993.
[26] K. Sato, M. Aoki, J. Tagaki, R. Noyori, J. Am. Chem. Soc. 17 (1997) 12386–12387.
[27] Z.P. Pai, P.V. Berdnikova, A.G. Tolstikov, T.B. Khlebnikova, N.V. Selivanova, Cataliz v
promyshlennosti 5 (2006) 12–23.
[8] A.K. Charykov, N.N. Osipov, Karbonovye kisloty i karboxilatnye komplexy v
[28] a) Z.P. Pai, T.B. Khlebnikova, Y.V. Mattsat, V.N. Parmon, React. Kinet. Catal. Lett. 98
khimicheskom analize, Khimija, Leningrad, 1991.
[9] N.T.A. Peres, J.R. Cursino-Santos, A. Rossi, N.M. Martinez-Rossi, World J. Microbiol.
Biotechnol. 27 (2011) 1719–1723.
[10] E.K. Ellingboe, Pat. US2203680, 1940.
[11] C.S. Morgan, J.W. Walker, Pat. US2847431, 1958.
(2009) 1–8;
b) T.B. Khlebnikova, Z.P. Pai, L.A. Fedoseeva, Y.V. Mattsat, React. Kinet. Catal. Lett. 98
(2009) 9–17.
[29] V.N. Parmon, Z.P. Pai, P.V. Oleneva, P.V. Berdnikova, L.V. Malysheva, Pat. RU2554000,
2015.
[12] E. Dos Santos, P. Metivier, Pat. US5864049, 1999.
[13] A. Bieser, G. Borsotti, F. Digioia, A. Ferrari, A. Pirocco, Pat. US2012/0302778, 2012.
[14] J.J. Mrowca, Pat. US4257973, 1981.