Catalytic properties of cobalt complexes with tetrapyrazino porphyrazine and phthalocyanine derivatives

Article abstract of DOI:10.1134/S0036024414120395

The catalytic activity of cobalt complexes with octaphenyltetrapyrazinoporphyrazine and phthalocyanine derivatives containing branched peripheral substituents is studied in heterogeneous catalysis of the oxidation of sodium diethyldithiocarbamate (SDC) with atmospheric oxygen. Cobalt phthalocyanines are shown to display higher catalytic activity than cobalt complexes with octaphenyltetrapyrazinoporphyrazine. The highest efficiency of heterogeneous catalysts is attained at temperatures of 298-303 K.

Full text of DOI:10.1134/S0036024414120395

ISSN 0036ꢀ0244, Russian Journal of Physical Chemistry A, 2014, Vol. 88, No. 12, pp. 2064–2067. © Pleiades Publishing, Ltd., 2014.
Original Russian Text © A.S. Vashurin, I.A. Kuzmin, N.A. Litova, O.A. Petrov, S.G. Pukhovskaya, O.A. Golubchikov, 2014, published in Zhurnal Fizicheskoi Khimii, 2014, Vol. 88,
No. 12, pp. 1904–1907.
CHEMICAL KINETICS
AND CATALYSIS
Catalytic Properties of Cobalt Complexes
with Tetrapyrazino Porphyrazine and Phthalocyanine Derivatives
A. S. Vashurin, I. A. Kuzmin, N. A. Litova, O. A. Petrov, S. G. Pukhovskaya, and O. A. Golubchikov
Ivanovo State University of Chemistry and Technology, Ivanovo, 153000 Russia
eꢀmail: asvashurin@mail.ru
Received January 10, 2014
Abstract—The catalytic activity of cobalt complexes with octaphenyltetrapyrazinoporphyrazine and phthaꢀ
locyanine derivatives containing branched peripheral substituents is studied in heterogeneous catalysis of the
oxidation of sodium diethyldithiocarbamate (SDC) with atmospheric oxygen. Cobalt phthalocyanines are
shown to display higher catalytic activity than cobalt complexes with octaphenyltetrapyrazinoporphyrazine.
The highest efficiency of heterogeneous catalysts is attained at temperatures of 298–303 K.
Keywords: porphyrazine, phthalocyanine, cobalt complex, heterogeneous catalysis, sodium diethyldithioꢀ
carbamate
DOI: 10.1134/S0036024414120395
INTRODUCTION
rasulfophthalocyaninates—are products of tonnage oil
processing [14–17]. The use of atmospheric oxygen in
their synthesis improves the quality of the target product
and is environmentally friendly [6, 9, 19, 20].
It is difficult to include phthalocyanine catalysts in
homogeneous catalysis due to their selfꢀassociation in
aqueous and aqueous alkaline media [21–23] and the
engineering complexity of their subsequent separation
and activation for recycling. The use of substituted
porphyrazine and phthalocyanine complexes as heterꢀ
ogeneous catalysts is therefore very promising.
Cobalt complexes of porphyrine compounds and
their analogues are finding increasingly wide application
as catalysts for the oxidation of olefins [1], cycloalkenes
[2], carbamates [3–5], and mercaptanes [6–10].
According to [11, 12], not only the central metal cation
in a macromolecule [13] but the nature of the peripheral
substituent affects the catalytic process with the particiꢀ
pation of tetrapyrrole macroheterocyclic compounds as
well. Cobalt complexes with phthalocyanines are thereꢀ
fore widely used to purify oil from sulfurꢀcontaining
products as active catalysts for the mild oxidation of
In this work, cobalt complex with octaphenyltetꢀ
mercaptanes and hydrogen sulfide [14, 15]. The probꢀ rapyrazinoporphyrazine (CoPA) was obtained and its
lem of their selective oxidation is also of great interest for catalytic properties were studied upon mild SDC oxiꢀ
the organic synthesis of industrialꢀgrade disulfides [8, dation with atmospheric oxygen in aqueous alkaline
15–18]. Dithiocarbamic acid derivatives—thiuram sulꢀ media, in contrast to the cobalt complexes of phthaloꢀ
fides synthesized via the oxidation of carbamates in cyanines (CoPcR1 and CoPcR2) synthesized earlier
aqueous alkaline solutions in the presence of cobalt tetꢀ with branched peripheral substituents:
R
R
N
N
N
N
N
N
N
N
N
N
Co
N
N
N
N
N
N
N
N
N
Co
N
N
R
O
N
R
R =
R =
(
CoPcR1)
O C
O C11H23
O C11H23
N
N
H O
N C
(
CoPcR2)
CoPA
2064

CATALYTIC PROPERTIES OF COBALT COMPLEXES
2065
1
upon the formation of CoPA, thus indicating the synꢀ
thesis of a chelate complex. Complexes CoPcR1 and
CoPcR2 were synthesized by the standard method in
[25]. Electronic absorption spectra were recorded on a
Shimadzu UV 1800 spectrophotometer in 10ꢀmm
thick quartz cells. The solvents were purified as
described in [26]. The SDC oxidation reaction was
studied in a lightꢀtight temperatureꢀcontrolled cell
keff
104, s− /g
0.8
×
0.6
0.4
0.2
650 mL in volume within a 2.7
×
10–3–8.3 10–3 mol/L
×
range of SDC concentrations at temperatures of 293–
313 K. Experiments were performed in aqueous alkaꢀ
line solutions at pH 8–10. A setup consisting of a therꢀ
mostat, a temperatureꢀcontrolled sampling cell, and
an oxygen delivery device was used. A reference samꢀ
ple was taken before each experiment. Experiments on
the oxidation of SDC without a catalyst were perꢀ
formed beforehand. To perform the catalytic oxidaꢀ
tion of SDC, a catalyst was added to the solution and
air was supplied to the cell through a capillary. The
moment air was supplied was considered as the beginꢀ
ning of the reaction. To determine the current SDC
concentration, samples 2 mL in volume were taken at
specific time intervals throughout each experiment.
The procedure for analytical spectrophotometric estiꢀ
mates of a current SDC concentration was described
in [27, 28].
290
295
300
305
310
315
, K
T
Fig. 1.
k
versus temperature for the oxidation of SDC in
eff
the presence of CoPA.
EXPERIMENTAL
Octaphenyltetrapyrazinoporphyrazine was syntheꢀ
sized as described in [24]. The free ligand was dissolved
in dimethylsulfoxide, and a hundredfold excess of
cobalt acetate was added. The reaction mixture was
heated to 313 K and allowed to stand for 60 min. The
solution was then evaporated. The dry mass was
washed with distilled water to remove any unreacted
RESULTS AND DISCUSSION
The catalytic activity of our cobalt complexes was
= 635 nm) in the visible investigated oxidizing SDC with atmospheric oxygen
salt. The absorption band (
λ
spectral region exhibits a 30ꢀnm hypsochromic shift according to the scheme
⎛
⎜
⎜
⎜
⎝
⎞
C2H5
C2H5
C2H5
C2H5
C2H5
C2H5
S
S
S
S
S
O2
⎟
–Na+
2
N C
N C
C N
–2Na+
⎟
(1)
⎟
S
⎠
It was established in preliminary experiments that where thiol exists in the form of RS– anions due to the
the noncatalytic oxidation of SDC is slow and is charꢀ equilibrium shifting to the right:
acterized by
k
eff = 1.7
×
10⎯ 5 s–1
.
RSH + NaOH
RS– + Na+ + H2O.
(4)
Under the condition of an unchanging oxygen
concentration, catalyst, and medium pH, the rate of
SDC oxidation is described by the firstꢀorder kinetic
equation [3, 29]
The first kinetic order obtained for SCD oxidation
in all of the systems within our range of concentrations
(2.7
×
10–3 to 8.3
×
10–3 mol/L) suggests that the forꢀ
mation of RS• particles with their subsequent converꢀ
sion into alkyldisulfide RS–SR is the rateꢀdeterminꢀ
ing stage of the oxidation process [11].
dc
/
d
τ
= –keffc
,
(2)
where
с
is the current SDC concentration,
τ
is the
Our study of the temperature dependence of the
efficiency of SDC oxidation in the presence of CoPA
revealed the nonlinear character of the change in keff
(Fig. 1). The highest efficiency was attained at a temꢀ
perature of 303 K. The rate of SDC oxidation grew by
time, keff is the effective reaction rate constant. This is
confirmed by the linear character of dependence ln
and the unchanging nature of the rate constants
calculated with the equation
eff = (1/ )ln(c0
c
=
f( )
τ
k
τ
/c),
(3)
a factor of 5, relative to noncatalytic oxidation (keff
7.5
=
10–5 s–1 g–1). Conversion in this case is 70–80%,
where с0 is the initial SDC concentration, and
c
is the
×
SDC concentration at a specific moment in time .
τ
due most likely to both the shift of equilibrium (4)
It should be noted that the catalytic oxidation of toward the formation of RS– anions and the higher
SDC proceeds efficiently only in alkaline media, efficiency of RS• radical formation.
RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A
Vol. 88
No. 12 2014

2066
VASHURIN et al.
1
media with the simultaneous distortion of its ꢀchroꢀ
π
keff
104, s−1 g−
×
mophore system and the formation of lowꢀtemperaꢀ
ture colorless products [31]. A 5–10% reduction in
catalytic activity that corresponding to technological
requirements was also observed for phthalocyanine
catalysts.
4
2
3
3
2
1
ACKNOWLEDGMENTS
This work was supported by the Russian Foundaꢀ
tion for Basic Research (project no. 13ꢀ03ꢀ00615ꢀa).
1
REFERENCES
1. S. Rayati, S. Zakavi, E. Bohloulbandi, et al., Polyheꢀ
0
2
4
6
8
10
dron 34, 102 (2012).
Number of cycle
2. A. Ghaemi, S. Rayati, and S. Zakavic, Macroheterocyꢀ
cles
3. A. S. Vashurin, S. G. Pukhovskaya, A. S. Semeikin, and
O. A. Golubchikov, Macroheterocycles (1), 72
(2012).
4. A. S. Vashurin, T. V. Tikhomirova, N. A. Futerman,
et al., Izv. Vyssh. Uchebn. Zaved., Khim. Khim. Tekhꢀ
nol. 55 (8), 122 (2012).
4, 18 (2011).
Fig. 2.
k
versus the number of oxidation cycles at 303 K
eff
for (1) CoPA, (2) CoPcR , and (3) CoPcR .
1 2
5
Phthalocyanine catalysts displayed better SDC oxiꢀ
dation efficiency even at 298 K. Effective SDC oxidation
rate constants
CoPcR1 and CoPcR2, respectively—an order of magꢀ
nitude higher than for CoPA.
keff = 3.5
×
10–4 and 2.3 10–4 s–1 g–1 for
×
5. K. Inoue, Progress Polym. Sci. 25, 453 (2000).
6. M. Hassanein, S. Gerges, M. Abdo, and S. ElꢀKhalafy,
The difference between the values of keff for phthaꢀ
locyanines CoPcR1 and CoPcR2 is quite likely due to
the effect of the spacer group of the peripheral substitꢀ
uent of a phthalocyanine molecule with the resulting
redistribution of electron density in the macrocyclic
ring. The nitrogen atom in the peripheral substituent
shifts the electron density to the macrocycle, thereby
hindering the coordination of dithiocarbamate and
oxygen to the central cobalt cation. In contrast, the
oxygen atom shifts the electron density from the macꢀ
roring, thereby raising the probability of SDC–phthaꢀ
locyanine–substrate coordination interactions.
When studying the catalytic activity of CoPA in a
series of consecutive experiments (Fig. 2), the catalyst
was found to deactivate by 60% as early as the second
catalytic cycle, limiting the possibilities for its indusꢀ
trial application. The behavior of this catalyst in subꢀ
sequent cycles is identical, and its activity remains
unchangeable up to the tenth cycle. However, even
though keff is 2.3 times higher than for noncatalytic
oxidation, this is insufficient to obtain highꢀpurity thiꢀ
uram sulfide.
J. Mol. Catal. A: Chem. 240, 22 (2005).
7. C. Fabbri, C. Aurisicchio, and O. Lanzalunga, Central
Eur. J. Chem. 6, 145 (2008).
8. V. N. Nemykin, A. E. Polshyna, S. A. Borisenkova, and
V. V. Strelko, J. Mol. Catal. A: Chem. 264, 103 (2007).
9. G. Ochoa, C. Gutierrez, I. Ponce, et al., J. Electroanal.
Chem. 639, 88 (2010).
10. T. Buck, H. Bohlen, and D. Wöhrle, J. Mol. Catal. A:
Chem. 80, 253 (1993).
11. M. Hoffman, Sci. Total Environ. 64, 99 (1987).
12. E. R. Birnbaum, M. W. Grinstaff, J. A. Labinger, et al.,
J. Mol. Catal. A: Chem. 104, L119 (1995).
13. B. D. Berezin and N. S. Enikolopyan, Metalloporphyꢀ
rins (Nauka, Moscow, 1988) [in Russian].
14. A. Kh. Sharipov, Khim. Tekhnol. Topl. Masel, No. 4, 4
(1994).
15. D. L. Burdick and W. L. Leffler, Petrochemicals in Nonꢀ
technical Language (PennWell, Tulsa, Oklahoma, 1990;
OlimpꢀBiznes, Moscow, 2001).
16. Yu. S. Marfin, A. S. Vashurin, E. V. Rumyantsev, and
S. G. Pukhovskaya, J. SolꢀGel Sci. Technol. 66, 306
(2013).
17. A. M. Mazgarov and A. F. Vil’danov, Pet. Chem. 39
,
CONCLUSIONS
336 (1999).
The drop in the catalytic activity of CoPA is likely
due to the saturation of its active sites and the formaꢀ
tion of oxygen adducts [30] that obstruct substrate–
porphyrazine–oxygen coordination interaction and
the transfer of electron pairs.
18. A. M. Mazgarov, A. F. Vil’danov, and S. N. Sukhov,
Khim. Tekhnol. Topl. Masel 40 (6), 11 (1996).
19. A. Goifman, J. Guna, V. Gitisa, et al., Appl. Catal. B:
Environ. 54, 225 (2004).
20. M. Kimura, Y. Yamaguchi, and T. Koyama, J. Porphyr.
Phthalocyan. 1, 309 (1997).
21. V. Iliev and A. Mihaylova, J. Photochem. Photobiol. A:
The reduction in catalytic activity upon moving
from CoPcR1 and CoPcR2 to CoPA is due to the
destruction of the macroring in strongly alkaline
Chem. 149, 23 (2002).
RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A
Vol. 88
No. 12 2014

CATALYTIC PROPERTIES OF COBALT COMPLEXES
2067
22. N. Sh. Lebedeva, N. A. Pavlycheva, O. V. Petrova, 27. I. V. Pimkov, Izv. Vyssh. Uchebn. Zaved., Khim. Khim.
et al., Mendeleev Commun. 13, 237 (2003).
Tekhnol. 50 (6), 111 (2007).
28. A. S. Vashurin, R. A. Badaukaite, N. A. Futerman,
23. W. J. Schutte, M. SluytersꢀRehbach, and J. H. Sluyters,
et al., Pet. Chem. 53, 221 (2013).
J. Phys. Chem. 97, 6069 (1993).
29. I. V. Pimkov, Candidate’s Dissertation in Chemistry
(Ivan. State Chem. Technol. Univ., Ivanovo, 2007).
24. E. M. Bauer, C. Ercolani, P. Galli, et al., J. Porphyr.
Phthalocyan. 3, 371 (1999).
30. L. C. Gruen and R. J. Blagrove, Austral. J. Chem. 26
,
25. T. V. Tikhomirova, V. E. Maizlish, G. P. Shaposhnikov,
et al., Zhidk. Kristally Praktich. Ispol’zov., No. 3, 83
(2010).
319 (1973).
31. O. A. Petrov, P. A. Stuzhin, and Yu. B. Ivanova, Russ. J.
Phys. Chem. A 82, 201 (2008).
26. A. Weissberger, E. Proskauer, J. Riddik, and E. Toops,
Organic Solvents (Intersci., New York, 1985; Inostr.
Liter., Moscow, 1958).
Translated by E. Glushachenkova
RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A
Vol. 88
No. 12 2014