Multicomponent cyclothiomethylation of phenylenediamines and 4,4'-diaminodiphenyls with formaldehyde and 1,2-ethanedithiol

Article abstract of DOI:10.1134/S1070363216070124

One-pot synthesis of bis-1,5,3-dithiazepanes by cyclothiomethylation of o-phenylenediamine, 4,4'-diaminodiphenyl, 4,4'-diaminodiphenyl oxide, and 4,4'-diaminodiphenylmethane with formaldehyde and 1,2- ethanedithiol was performed. Sorption properties of th

Full text of DOI:10.1134/S1070363216070124

ISSN 1070-3632, Russian Journal of General Chemistry, 2016, Vol. 86, No. 7, pp. 1608–1612. © Pleiades Publishing, Ltd., 2016.
Original Russian Text © G.R. Khabibullina, Е.S. Fedotova, G.R. Anpilogova, V.R. Akhmetova, А.G. Ibragimov, 2016, published in Zhurnal Obshchei
Khimii, 2016, Vol. 86, No. 7, pp. 1130–1134.
Multicomponent Cyclothiomethylation of Phenylenediamines
and 4,4'-Diaminodiphenyls with Formaldehyde
and 1,2-Ethanedithiol
G. R. Khabibullinaa, Е. S. Fedotovaa, G. R. Anpilogovab,
V. R. Akhmetovaa, and А. G. Ibragimova
a Institute of Petrochemistry and Catalysis, Russian Academy of Sciences, pr. Oktyabrya 141, Ufa, 450075 Russia
е-mail: ink@anrb.ru
b Ufa Institute of Chemistry, Russian Academy of Sciences, Ufa, Russia
Received December 30, 2015
Abstract—One-pot synthesis of bis-1,5,3-dithiazepanes by cyclothiomethylation of о-phenylenediamine, 4,4'-
diaminodiphenyl, 4,4'-diaminodiphenyl oxide, and 4,4'-diaminodiphenylmethane with formaldehyde and 1,2-
ethanedithiol was performed. Sorption properties of the newly synthesized bis[4-(1,5,3-dithiazepan-3-yl)-
phenyl] oxide were investigated by the batch technique. High efficiency of the recovery of palladium(II) with
this reagent from hydrochloric acid solutions at room temperature was shown.
Keywords: cyclothiomethylation, aromatic diamines, formaldehyde, 1,2-ethanedithiol, bis-1,5,3-dithiazepanes,
palladium(II) sorption
DOI: 10.1134/S1070363216070124
Multicomponent cyclothiomethylation of aromatic
diamines by the reaction with formaldehyde and hyd-
rogen sulfide proceeds as intra- or intermolecular con-
densation with the formation of bis-dithiazinanes or
benzocrown thiaazaethers [1]. Multicomponent reac-
tion of cyclothiomethylation of aliphatic diamines [2–
5], hydrazine [6–9], and NH4Cl [10] with aldehydes
and hydrogen sulfide results in the formation of bis-
dithiazinanes or bicyclic compounds, while when
using CH2O and 1,2-ethanedithiol as a thiomethylating
mixture bis-1,5,3-dithiazepanes [11–13] are formed.
So far, the reaction of aromatic diamines with formal-
dehyde and 1,2-ethanedithiol was not studied.
of о-,m-,p-phenylenediamines, 4,4'-diaminodiphenyl,
4,4'-diaminodiphenyl oxide, and 4,4'-diaminodiphenyl-
methane with formaldehyde and 1,2-ethane-dithiol.
It was found that о-phenylenediamine enters the
reaction of heterocyclization with CH2O and 1,2-
ethanedithiol (ratio 1 : 4 : 2, 60ºС) in the mixture
СНСl3–EtOH (method a) with participation of two
aminogroups to form 3,3'-(1,2-phenylene)-bis-1,5,3-
dithiazepane 1 in 35% yield and complex mixture of
oligomers up to 60% by the reaction of intermolecular
condensation. Under similar conditions, 4,4'-diamino-
diphenyls form bis-(1,5,3-dithiazepan-3-yl)phenyls 2,
3a, and 3b in 40, 46, and 51% yield, respectively
(Scheme 1). Difficultly separable oligomeric products
of intermolecular condensation of 4,4'-diaminodi-
phenyls with CH2O and 1,2-ethanedithiol are formed
as by-products.
The structure of products was established by IR, 1Н
and 13С NMR spectroscopy and МALDI TOF mass-
spectrometry. Spectral and physicochemical charac-
teristics of compounds 1 and 3a are consistent with the
literature data [15, 17]. The structure of compound 1 is
proved by X-ray diffraction (XRD) analysis (Fig. 1).
Saturated sulfur- and nitrogen-containing hetero-
cyclic compounds, which are insoluble in water and
diluted solutions of mineral acids, are of interest as
complex-forming sorbents and extracting agents for
“soft” ions of metals of platinum group, gold, silver,
and mercury [12, 14–16].
In order to elaborate the effective method for the
synthesis of novel aryl-containing bis-1,5,3-dithiazepanes
possessing potentially high sorption activity
towards noble metal ions we have studied the reaction
1608

MULTICOMPONENT CYCLOTHIOMETHYLATION OF PHENYLENEDIAMINES
1609
Scheme 1.
S
S
NH2
H2N
NH2
S
S
N
N
S
S
HS
HS
S
S
NH2
O
H
+
H
N
N
1 : 4 : 2
60oC
1 : 4 : 2
60oC
2
1 : 4 : 2
60oC
X
H2N
NH2
1
S
S
S
N
X
N
S
3a, 3b
X = CH2 (a), O (b).
From the viewpoint of minimization of the number
of stages, multicomponent reactions are the most
rational and effective methods for the synthesis of
heterocyclic systems. With this in mind, we have
performed the synthesis of bis-1,5,3-dithiazepanes 1–3
in up to 60% yields by the reaction of cyclothio-
methylation of aromatic diamines using SmСl3·6Н2О
as a catalyst (method b).
intermolecular condensation was observed. The
reaction of intermolecular cyclothiomethylation with
participation of long-chain α,ω-dithiols with the
formation of macroheterocycles was successful only
when monoaminoalcohols were used [18].
Earlier we have shown that bis-1,5,3-dithiazepanes
obtained from NH4Cl, hydrazine, and ethylenediamine
are efficient sorbents for palladium(II) and silver(I)
[12]. Therefore, it was reasonable to assume that
compounds 2 and 3, which are insoluble in water and
dilute HCl solutions, also possess sorption activity
towards “soft” noble metal ions. Sorption pro-perties
were investigated by the example of compound 3b for
sorption of palladium(II) from hydrochloric acid
solutions in batch experiments. Compound 3b is a fine-
crystalline substance with bulk density 0.63 g/cm3. The
In contrast to the о-isomer, m-phenylenediamine
with СН2О and 1,2-ethanedithiol forms a mixture of
poorly soluble and nonidentified oligomers due to the
intermolecular condensation. The p-isomer does not
enter the reaction with the above reagents because of
its ability to catalyze the condensation of СН2О with
SH-acids, as in the case of cyclothiomethylation with
the mixture CH2O–H2S [1].
Note that during the multicomponent cyclization of
о-phenylenediamine with CH2O and H2S the amino
groups are linked together by the methylenesulfide
links [1], whereas with the mixture CH2O–1,2-
ethanedithiol the cyclothiomethylation occurs inde-
pendently with each amino group. A similar trend is
observed for the reaction of cyclothiomethylation of
hydrazine [5, 6] and ethylenediamine [2-4], which with
CH2O and H2S give bicyclic products, while with the
mixture CH2O–1,2-ethanedithiol bis-1,5,3-dithiaze-
panes are formed.
In order to extend the scope of the multicomponent
cyclothiomethylation we tried to bring in the reaction
with the aforementioned aromatic diamines the long-
chain aliphatic α,ω-dithiols (1,3-, 1,4-, 1,5-alkane-
dithiols). However, in both methods (a and b) the
formation of complex mixtures of products of
Fig. 1. General view of the molecule of compound 1 in the
crystal.
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KHABIBULLINA et al.
qPd, mmol/g
F
τ, min
сHCl, mol/L
Fig. 3. Initial part of kinetic curve of sorption of palladium(II)
with compound 3b from 0.0207 mol/L solution of K2PdCl4
at the acidity of aqueous phase of 4 mol/L HCl and m : V =
1 : 400. F = qPd/qPd eq is the degree of reaching the
equilibrium of palladium(II) sorption.
Fig. 2. Dependence of sorption capacity of compound 3b
towards palladium(II) on the initial HCl concentration in
the solution. The initial concentration of K2PdCl4 is
0.0203 mol/L, m : V = 1 : 400.
content of electron-donating atoms S and N to the unit
of mass of the compound is, from the data of elemental
analysis, qS = 8.80 mg-at S/g and qN = 4.70 mg-at N/g
respectively. The value of ion-exchange capacity
q0.1 N HCl = 0.80 mg-equiv/g (the ratio of the sorbent
mass m, g, and the volume of solution V, cm3, was
1 : 100) corresponds to the 17% degree of protonation
of amino groups and suggests a low basicity of
compound 3b. As follows from Fig. 2, the extraction
of palladium(II) from the solutions of 0.1–0.5 mol/L
HCl is negligeable (distribution coefficient Kd < 4 cm3/g).
With the increase of concentration of HCl above
0.5 mol/L the sorption capacity of compound 3b to
palladium(II) increases and in the range 4–5 mol/L
HCl it reaches the maximum value qPd = 6.80 mmol/g
(Kd = 2061 cm3/g). For optimal acidity of aqueous
phase of 4 mol/L HCl the time of reaching half of
sorption equilibrium is 12 min (Fig. 3), the time of
reaching sorption equilibrium is ~14 h. A strongly
convex form of the palladium(II) sorption isotherm
and a high value of the maximum sorption capacity
qPd max = 6.84±0.10 mmol/g suggests a high sorption
affinity of compound 3b to palladium(II) at the optimal
concentration of HCl. The ratio qPd max : (qS + qN) =
1 : 2 allows to assume that thioether and protonated
amino groups of compound 3b are involved in the
interaction with palladium(II). Apparently, compound
3b forms with palladium(II) complexes with coor-
dination units [PdCl2S2], where S are electron-donating
sulfur atoms, and ionic associates of the type (AmH+)2·
PdCl42–, where Am are tertiary amino groups [14].
Therefore, using the method of multicomponent
cyclothiomethylation of о-phenylenediamine and 4,4'-
diaminodiphenyls under the action of formaldehyde
and 1,2-ethanedithiol the compounds of bis-1,5,3-
dithiazepane structure were synthesized, promising
sorbents for palladium(II) ions. The use of SmСl3·
6Н2О as a catalyst increases the yield of the target
products to 60%. Bis[4-(1,5,3-dithiazepan-3-yl)-
phenyl] oxide is shown to be highly efficient sorbent
for extraction of palladium(II) from solutions of 3–
5 mol/L НСl at room temperature.
EXPERIMENTAL
Commercially available (Acros) о-phenylenedi-
amine, 4,4'-diaminodiphenyl, 4,4'-diaminodiphenyl
oxide, 4,4'-diaminodiphenylmethane, and 1,2-ethane-
dithiol of no less than 98% purity and formaldehyde
(37% water solution) were used without further
purification. For preparation of aqueous solutions of
palladium(II) K2PdCl4 synthesized by the known
procedure and HCl of “chemically pure” grade were used.
1Н and 13С NMR spectra were registered on a
Bruker Avance 400 spectrometer with working
frequency 400.13 (1H) and 100.62 (13С) MHz in using
CDCl3 or DMSO-d6 as solvents. Mass spectra were
recorded on a AUTOFLEX III MALDI TOF Bruker
mass spectrometer, the samples of the compounds
were prepared by the “dried droplet method” (1 : 10)
using α-cyano-4-hydroxycinnamic or 2,5-dihydro-
benzoic acid as a matrix. IR spectra were recorded on a
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MULTICOMPONENT CYCLOTHIOMETHYLATION OF PHENYLENEDIAMINES
1611
Bruker Vertex 70v spectrophotometer from mulls in
mineral oil in the range 4000–500 cm–1. Analysis on С,
Н, N in the products was performed using СHN-OS
analyzer CarloErba-1106, the content of sulfur was
determined using the Schöniger method [19]. The
melting points were determined on an RNMK 80/2617
hot stage. TLC was performed on Silufol W-254
plates, chromatograms were developed in the iodine
chamber. Silica gel KSK (100–200 μm) was used for
column chromatography.
[15]), Rf 0.88 (CH2Сl2–Et2O–AcOEt, 5 : 5 : 1). 1Н and
13С NMR spectra are identical to the earlier described
[15]. IR spectrum, ν, cm–1: 635, 722 (С–S), 1462, 1610
(Ar), 2854, 2923 (CH2). Mass spectrum (MALDI
TOF), m/z: 433.070 [М – Н]+. Found, %: С 58.51, Н
6.08, N 6.61, S 28.94. С21Н26N2S4. Calculated, %: С
58.02, Н 6.03, N 6.44, S 29.51. М 434.098.
Bis[4-(1,5,3-dithiazepan-3-yl)phenyl] oxide (3b).
Yield 0.26 g (60%), mp 142–144°С, Rf 0.88 (hexane–
ethyl acetate, 1 : 2). IR spectrum, ν, cm–1: 581, 638,
678 (С–S), 1228 (C–N), 1196, 1229 (С–О–С), 1462
(CH2), 1606 (Ar), 2855, 2923 (CH2). 1Н NMR
spectrum (CDCl3), δН, ppm: 3.02 br.s (4Н, СН2СН2S),
4.81 br.s (4Н, NСН2S), 6.97–7.04 m (8Н, НСAr). 13С
NMR spectrum (DMSO-d6), δС, ppm: 36.0 (СН2СН2S),
55.9 (NСН2S), 117.8 (Рh), 119.5 (Рh), 141.9 (Рh),
151.5 (Рh). Mass spectrum (MALDI TOF), m/z: 436.065
[М]+. Found, %: С 54.65, Н 5.55, N 6.60, S 29.20.
С20Н24N2ОS4. Calculated, %: С 55.01, Н 5.54, N 6.42,
О 3.66, S 29.37. М 436.077.
General procedure for cyclothiomethylation of
aromatic diamines. a. A mixture of 1,2-ethanedithiol
(0.17 mL, 2 mmol) and formaldehyde water solution
(37%, 0.3 mL, 4 mmol) was stirred at room
temperature (~20ºС) for 30 min, then heated to 50ºС,
and 1 mmol of aromatic diamine was added dropwise
(0.108 g of о-phenylenediamine, 0.184 g of 4,4'-di-
aminodiphenyl, 0.198 g of 4,4'-diaminodiphenylmethane,
0.2 g of 4,4'-diaminodiphenyl oxide) dis-solved at 40°С
in 15 mL of EtOH (for о-phenyl-enediamine, in СНСl3–
EtOH, 1 : 3), and the mixture was stirred for 6 h at
~60°С. The formed precipitate was separated by
fractional crystallization, dried, and purified by column
chromatography (compound 2 was isolated by frac-
tional crystallization without further purification).
Sorption characteristics of compound 3b were
investigated by the batch method of separate
specimens at 20±0.5ºС, ratio of the sorbent mass (g)
and the volume of solution (cm3) m : V = 1 : 100–1 :
800 rpm (magnetic stirrer ММ 2А) and time of phase
contact 24 h. To obtain the palladium(II) sorption
kinetic curve the time of phase contact varied from
5 min to 114 h. The values of q0.1 N HCl and sorption
capacity towards palladium(II) were determined
according to [20]. The concentration of palladium(II)
in aqueous solutions was determined spectrophoto-
metrically with SnCl2 [21] on a Specord M40 spectro-
photometer.
b. The syntheses were carried out as above with
addition after the aromatic diamine of 0.02 g of
SmCl3·6H2O (5 mol %) as a catalyst. The yields here-
inafter are given for method b.
3,3'-(1,2-Phenylene)bis-1,5,3-dithiazepane
(1).
Yield 0.13 g (39%), mp 212–214°С (mp 210–212°С,
1
[15]), Rf 0.90 (С6Н6–EtOH, 5 : 1). Н and 13С NMR
spectra are identical to those early described [15].
Found, %: С 48.89, Н 5.96, N 8.02, S 37.14. С14Н20N2S2.
Calculated, %: С 48.80, Н 5.85, N 8.13, S 37.22.
XRD analysis of compound (1). Cell parameters
and intensities of 4315 independent reflections were
measured on a single crystal diffractometer “Xcalibur
Gemini Еos” equipped with EOS CCD spatial detector
and graphite monochromator, MoKα-radiation, λ =
0.71073 Å, ω-scanning, 2θmax = 62°. The collection
and the treatment of the data was performed using
CrysAlisPro Oxford Diffraction Ltd program [22].
Crystals of compound 1 monoclinic, C14H20N2S4, M =
344.56, unit cell parameters: a = 19.9545(15), b =
8.4392(7), c = 9.6594(8) Å, β = 96.372(7)°, V =
Bis[4-(1,5,3-dithiazepan-3-yl)phenyl] (2). Yield
0.20 g (48%), mp 192–195°С. IR spectrum, ν, cm–1:
1
630, 676 (С–S), 1609 (Ar), 2854, 2923 (CH2). Н
NMR spectrum (DMSO-d6), δН, ppm: 3.11 br.s (4Н,
СН2СН2S), 4.83 br.s (4Н, NСН2S), 6.99 d (4Н, НСAr,
J = 8.0 Hz), 7.53 d (4Н, НСAr, J = 8.0 Hz). 13С NMR
spectrum (DMSO-d6), δC, ppm: 35.7 (СН2СН2S), 54.9
(NСН2S), 116.1 (Рh), 127.4 (Рh), 132.5 (Рh), 144.5
(Рh). Mass spectrum (MALDI TOF), m/z: 420.182 [М]+.
Found, %: С 57.01, Н 5.67, N 6.72, S 30.71. С20Н24N2S4.
Calculated, %: С 57.10, Н 5.75, N 6.66, S 30.49. М
420.082.
1616.6(2) Å3, space group P21/c, Z = 4, dcalc
=
1.416 mg/mm3. The structure was solved by the direct
method and refined using SHELX program [23] in
OLEX2 software [24] by full-matrix least-squares
method in anisotropic approximation. Hydrogen atoms
Bis[4-(1,5,3-dithiazepan-3-yl)phenyl]methane (3а).
Yield 0.23 g (54%), mp 144–146°С (mp 145–147°С
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 86 No. 7 2016

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KHABIBULLINA et al.
10.1007/s11172-009-0140-1.
were included in the refinement with fixed position
and temperature parameters. In calculations 2265
reflections were used with I > 2σ(I). The final
divergence factors are R = 0.0823 and wR2 = 0.2359.
Crystallographic data of the structure were deposited
to the Cambridge Crystallographic Data Centre
(CCDC-1430902).
9. Akhmetova, V.R., Murzakova, N.N., Khabibullina, G.R.,
Tyumkina, T.V., Starikova, Z.A., Bushmarinov, I.S.,
and Korzhova, L.F., Russ. Chem. Bull., 2012, vol. 61,
no. 1, p. 141. DOI: 10.1007/s11172-012-0020-y.
10. Akhmetova, V.R., Khabibullina, G.R., Galimzyanova, N.F.,
Kunakova, R.V., and Ibragimov, A.G., J. Heterocyclic
Chem., 2015. DOI: 10.1002/jhet.2344.
ACKNOWLEDGMENTS
11. Khabibullina, G.R., Akhmetova, V.R., Bushmarinov, I.S.,
and Ibragimov, A.G., Russ. J. Org. Chem., 2013, vol. 49,
no. 10, p. 1563. DOI: 10.1134/S1070428013100229.
12. Akhmetova, V.R., Anpilogova, G.R., Khabibullina, G.R.,
Akhmadiev, N.S., and Ibragimov, A.G., Russ. J. Appl.
Chem., 2014, vol. 87, no. 5, p. 585. DOI: 10.1134/
S1070427214050085.
This work was performed with the financial support
by the Program of Department of Chemistry and
Material Sciences of the Russian Academy of Sciences
and by the Russian Foundation for Basic Research
(grants nos. 14-03-00240-а, 14-03-97023-r_Povolzhie_а).
13. Akhmetova, V.R., Murzakova, N.N., Tyumkina, T.V.,
Khabibullina, G.R., Bushmarinov, I.S., Korzhova, L.F.,
and Galimzyanova, N.F., Russ. Chem. Bull., 2012,
vol. 61, no. 11, p. 2140. DOI: 10.1007/s11172-012-0301-5.
14. Murinov, Yu.I., Maistrenko, V.N., and Afzaletdinova, N.G.,
Ekstraktsiya metallov S,N-organicheskimi soedine-
niyami (Extraction of Metals by S,N-Organic
Compounds), Мoscow: Nauka, 1993.
The structural studies of compounds were per-
formed with the use of Collective Usage Centre
“Agidel” at Institute of Petrochemistry and Catalysis
of Russian Academy of Sciences.
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