Long-chain alkyl esters of O,O-dialkyl dithiophosphoric and thionophosphoric acids prepared on the basis of red phosphorus, elemental sulfur, alcohols, and industrial fractions of higher monoolefins

Article abstract of DOI:10.1080/10426507.2014.951999

Mixtures of long chain S-alkyl O,O-dialkyl dithiophosphates, and O-alkyl O,O-dialkyl thionophosphates were obtained by the reaction of red phosphorus with elemental sulfur, alcohols, and industrial fractions of C₁₆-C₁₈ and C₂₀-C₂₆ of higher olefins in the presence of Lewis acid catalysts. The products obtained possess high anticorrosion activities toward mild steel.

Full text of DOI:10.1080/10426507.2014.951999

Phosphorus, Sulfur, and Silicon, 190:484–493, 2015
Copyright ꢀC Taylor & Francis Group, LLC
ISSN: 1042-6507 print / 1563-5325 online
DOI: 10.1080/10426507.2014.951999
LONG-CHAIN ALKYL ESTERS OF O,O-DIALKYL
DITHIOPHOSPHORIC AND THIONOPHOSPHORIC ACIDS
PREPARED ON THE BASIS OF RED PHOSPHORUS,
ELEMENTAL SULFUR, ALCOHOLS, AND INDUSTRIAL
FRACTIONS OF HIGHER MONOOLEFINS
Ilyas S. Nizamov,1,2 Radik R. Shamilov,2 Ramazan Z. Salikhov,2
Ilnar D. Nizamov,1 Yuriy P. Khodyrev,1
and Elvira S. Batyeva1
1State Budgetary-Funded Institution of Science, A. E. Arbuzov Institute of Organic
and Physical Chemistry of Kazan, Scientific Center of Russian Academy of
Sciences, Kazan, Russian Federation
2Kazan Federal University, Kazan, Russian Federation
GRAPHICAL ABSTRACT
S
S
+ S +
+
0.25 H2S
0.25 (RO)2POH
+
0.25 (RO)2PSH
ROH
0.5 Pred
3a-c
4a-c
R = Bu-i (3a, 4a), Oct-i (3b, 4b), Pr-i (3c, 4c)
Abstract Mixtures of long chain S-alkyl O,O-dialkyl dithiophosphates, and O-alkyl O,O-
dialkyl thionophosphates were obtained by the reaction of red phosphorus with elemental
sulfur, alcohols, and industrial fractions of С16–С18 and С20–С26 of higher olefins in the
presence of Lewis acid catalysts. The products obtained possess high anticorrosion activities
toward mild steel.
Keywords Red phosphorus; sulfur; alcohols; higher olefins; anticorrosion activity
INTRODUCTION
The tetracoordinated phosphorus organic dithioacids as well as their esters and salts
have found an expanding application as agricultural insecticide and pesticide derivatives,1–5
antiwear oil lubricant additives,6 surface-active agents, emollients, washing agents, wetting
agents and detergents, dispersing agents, and versatile chelating ligands.7–10 The dithio-
phosphate derivatives have played a key role as corrosion inhibitors of mild steel.11–13
Received 6 May 2014; accepted 2 August 2014.
Address correspondence to Ilyas S. Nizamov, Kazan Federal University, Kazan, Russian Federation.
E-mail: isnizamov@mail.ru
Color versions of one or more of the figures in the article can be found online at www.tandfonline.com/gpss.
484

LONG-CHAIN ALKYL THIOPHOSPHATES
485
These compounds involve nonpolar hydrocarbon chains as well as a S=P S group.
Low-chain O,O-dialkyl S-alkyl dithiophosphates were prepared by the reactions of O,O-
dialkyl dithiophosphoric acids with hexadec-1-ene, octadec-1-ene, 2-methylpentadec-1-
ene, 2-methylheptadec-1-ene, and 2-methylpent-1-ene in the presence of zinc chloride
and under ultrasound irradiation.14–16 However, the chemical behavior of nonactivated
simple higher (С16 and С18 and higher) α-monoolefins in the similar reactions appear
to have attracted little attention. Thus, we have managed to obtain long chain S-alkyl
O,O-dialkyl dithiophosphates by the addition of O,O-dialkyl dithiophosphoric acids at the
carbon–carbon double bond of higher monoolefins of industrial fractions of С16–С18 and
С20–С26.12 High inhibition efficiency has been found for long chain S-alkyl O,O-dialkyl
dithiophosphates.12 Taking into account that O,O-dialkyl dithiophosphoric acids have usu-
ally been prepared by the reaction of tetraphosphorus decasulfide with alcohols,17 we have
decided to use mixtures of red phosphorus and elemental sulfur instead of tetraphospho-
rus decasulfide. We have already reported our preliminary results on the reaction of red
phosphorus with sulfur, alcohols, and higher olefins of industrial fractions of С16–С18
and С20–С26 as an abstract of conference report18 without experimental details and struc-
ture identification. So in this article experimental details of this reaction are presented.
The mixture of long chain S-alkyl O,O-dialkyl dithiophosphates and O-alkyl O,O-dialkyl
thionophosphates were tested as inhibitors for carbon dioxide corrosion of mild steel using
polarization curves.
RESULTS AND DISCUSSION
We have previously established content and structure of higher olefins of industrial
fractions of С16–С18 and С20–С26 manufactured by Join Stock Company “Nizhnekamsk-
1
neftekhim” (Russian Federation) by H NMR spectroscopy, mass spectrometry, and GC
analyses.19 The fraction of С16–С18 mainly includes vinylidene α-olefins 1a 25.6%, linear
С16 and С18 α-olefins 1b 61.6%, and inner С16 and С18 olefins 1c 12.8%. The fraction
С20–С26 mostly contains the olefins of С20 (the overall content of С20 is 31.7%), С22
(26.0%), С24 (16.4%), and С26 (12.9%) involving С28 (7.8%) and involves vinylidene α-
olefins 2a, linear α-olefins 2b, and minor amounts of spatially hindered olefins with inner
C=C 2c.19
It should be noted that the complicacy of the contents of industrial fractions С16–С18
and С20–С26 olefins can lead to intricate mixtures of the addition products of phospho-
rus thioacids into the C=C bond. Ethanol, 1-propanol, 1-butanol, 1-pentanol, heptanol,
1-octanol, and 1-dodecanol have been reported to react with red phosphorus and sulfur in
ratio of 1:1:1 at 100–150◦C for 3–24 h to form mixtures of O,O-dialkyl dithiophosphoric
acids (the main products) and O,O-dialkyl thionophosphoric acids (the minor products).20
Indeed, we have confirmed that the reaction of red phosphorus and sulfur with iso-butanol,
iso-octanol, and iso-propanol has been completed by heating the reactants at 100–110◦C
for 6–12 h with the minor formation of O,O-dialkyl thionophosphoric acids 3a–c (δР
= 64 ppm) and the main formation of O,O-dialkyl dithiophosphoric acids 4a–c (δР
=
86 ppm; Scheme 1). The 31P NMR resonances at 64 and 86 ppm are typical for dithio-
phosphoric and thionophosphoric acids.21 It should be emphasized that the ratio of red
phosphorus/sulfur/iso-butanol as 2:5:4 corresponds to the stoichiometry of the reaction
of tetraphosphorus decasulfide with alcohols.22 At this ratio at 100◦C for 10 h we have
obtained mixtures of O,O-di-iso-butyl dithiophosphoric acids 4a as main product (90%,
δР = 86.8 ppm) and O,O-di-iso-butyl thionophosphoric acids 3a (10%, δР = 64.3 ppm) as
minor product.

486
I. S. NIZAMOV ET AL.
S
S
+ S +
+
0.25 (RO)2POH
ROH
+
0.25 (RO)2PSH
0.5 Pred
0.25 H2S
3a-c
4a-c
R = Bu-i (3a, 4a), Oct-i (3b, 4b), Pr-i (3c, 4c)
Scheme 1
There is no need to isolate the thioacids 3a–c and 4a–c. The reaction mixtures obtained
(see Scheme 1) were treated by olefins 1a–c and 2a–c in the presence of 2–3 wt% of ZnCl2
as Lewis acid catalyst at 80◦C for 4 h to form S-alkyl O,O-dialkyl dithiophosphates 5a–e
and 6a–e (δр = 90 and 94 ppm, respectively) and O-alkyl O,O-dialkyl thionophosphates
7a–e and 8a–e (Scheme 2).23 The inner olefins 1c and 2c and minor amounts of phosphorus
thioacids formed from these olefins are not shown in Scheme 2.
S
H3C
S
CH3
CH3
0.12 CH3(CH2)nC-S-P(OR)2
+
+
0.12 CH3(CH2)nCH-S-P(OR)2
CH3(CH2)n-C=CH2
CH3
1) 0.5 Pred + S + ROH
- H2S
6a-e
1a,b
5a-e
+
S
H3C
H3C
CH3(CH2)n-CH=CH2
2) ZnCl2
S
0.12 CH3(CH2)nC-O-P(OR)2
0.12 CH3(CH2)nCH-O-P(OR)2
+
2a,b
CH3
8a-e
7a-e
R = Bu-i (5a, 6a, 7a, 8a, 5e, 6e, 7e, 8e),
Oct-i (5b, 6b, 7b, 8b, 5d, 6d, 7d, 8d); Pr-i (5c, 6c, 7c, 8c)
From fraction of C -C18: n = 12, 14 (1a, 5a, 7a, 5b, 7b, 5c, 7c), 13, 15 (1b, 8a, 6a, 6b, 8b, 6c, 8c);
16
From fraction of C -C26: n = 16, 18, 20, 22 (2a, 5e, 7e, 5d, 7d), 17, 19, 21, 23 (2b, 6e, 8e, 6d, 8d)
20
Scheme 2
The products 5, 6, 7, and 8 were not isolated as individual compounds but charac-
terized as the mixtures. Compounds 5c, 6c, 7c, and 8c (with iso-propoxy groups) were
purified by column chromatography on silica gel. The 31P NMR signals of the intermediate
products 3a–c and 4a–c disappeared when the reaction (Scheme 2) was completed. The 31P
NMR spectra of minor thionophosphates 7a–e and 8a–e show signals in the field of δР =
69.1–69.9 ppm. These signals are in accordance with literature data.21 Thus, O-iso-propyl
O,O-diethyl thionophosphate and tri-iso-butyl thionophosphate are known to possess sig-
nals in the 31P NMR spectra at δР = 69.0 and 68.3 ppm, respectively.21 In the reactions
of red phosphorus, sulfur, iso-butanol or iso-octanol with olefins 1a–c, the ratio between
dithiophosphate 5a–e, 6a–e, and thionophosphates 7a–e, 8a–e is 2:1 whereas in the reac-
tions of olefins 2a–c with red phosphorus, sulfur, iso-butanol, the ratio between 5a–e, 6a–e,
and 7a–e, 8a–e is 9:1.
The reactions studied (Scheme 2) have been found to bring about the formation of
1
products as Markovnikov’s adducts. The H NMR spectra of all products 5, 6, 7, and 8
show characteristic resonances due to the presence of the methyl protons of a СН3СH2CH2
fragment. Thus, a large triplet at δ = 0.90 ppm (3JНH = 7.2 Hz) was assigned to the methyl
protons of the СН3СH2CH2 fragment of the main products 5c and 6c, whereas a little triplet

LONG-CHAIN ALKYL THIOPHOSPHATES
487
at δ = 0.97 ppm (3JНH = 7.2 Hz) was attributed to the same protons of the minor products
7c and 8c. The 1H NMR spectrum of 6a exhibits a multiplet at δ = 3.03 ppm for the methine
proton of the PSCH(CH3)CH2 fragment. A siglet observed at δ = 1.59 ppm is assigned to
the methine proton of the PSCHCH2 fragment of 5a. The methylene protons attached to
the oxygene atom [the (CH2CH2О)2Р fragment] of 5b, 6b, 7b, and 8b (with iso-octyloxy
groups) appeared as two doublet of triplets at δ = 3.97 and 4.05 ppm (3JНH = 8.5 Hz,
3JPH = 5.1 Hz, 5b, 6b and 3JНH = 8.5 Hz, 3JPH = 5.8 Hz, 7b, 8b). The methyl protons of
the [(СН3)2CHО]2Р fragment of 5c, 6c, 7c, and 8c (with iso-propoxy groups) appear as a
doublet at δ = 1.38 ppm (3JНH = 6.3 Hz). The methyl protons of the [(СН3)2CHCH2О]2Р
groups of 5e, 6e, 7e, and 8e (with iso-butoxy groups) reveal a doublet at δ = 0.98 ppm
(3JНH = 6.4 Hz}.
1
The 13C-{ H} NMR spectra of 5a, 6a, 7a, and 8a show a doublet at δ = 36.7 ppm that is
being attributable to the carbon atom of the PSСH fragment of 6a (2JPC = 5.9 Hz), a doublet
at δ = 41.3 ppm (PSС, 5a, 2JPC = 5.5 Hz), a singlet at δ = 67.4 ppm (POСHCH2CH2, 8a),
and a singlet at δ = 70.0 [POС(CH3)2CH2, 7a].
The ESI mass spectrum of 5a, 6a, 7a, and 8a exhibits the mass peak m/e 478.3 due to
molecular ions [M]+ of 7a and 8a, formed from olefins of C18 (calculated molecular mass
M 7a and 8a is 478.8). The peaks m/e 554.6 and 1009.6 were assigned to ions [М + Na
+ K]+ and [2М + K]+ where M is the molecular mass of 5a and 6a (M 466.8) resulting
from C16 olefins. The esters 5a and 6a formed from C18 olefins give a peak m/e 1049.1 of
ion [2М + Na + K]+ (requires 494.8).
The bands at ν 675 and 553 cm−1 in the IR spectrum of 5a, 6a, 7a, and 8a are assigned
to the P S and P S stretching vibrations. The band at ν 999 cm−1 is due to the stretching
vibration of the (P)O C bond. The band of the symmetrical deformation vibrations of the
germinal (СН3)2C group appeared at ν 1377 cm−1
.
There is no need to prepare intermediate tetraphosphorus decasulfide or O,O-dialkyl
dithiophosphoric acids. Long chain S-alkyl O,O-dialkyl dithiophosphates and O-alkyl O,O-
dialkyl thionophosphates obtained possess thiophosphoryl and dithiophosphoryl groups
which can coordinate to iron atoms.13 It is noteworthy that carbon dioxide corrosion of
mild steel is a very serious problem in the oil and gas production industry.24,25 So we
have decided to study the inhibition effectiveness upon CO2 corrosion of mild steel for
the mixtures of 5, 6, 7, and 8. Data of inhibition coefficient (γ ) and inhibition efficiency
(η) with different concentrations of 5, 6, 7, and 8 are presented in Table 1. The inhi-
bition efficiency reached 91.8% when compounds 5a, 6a, 7a, and 8a with iso-butoxy
groups are introduced into the standard brine in a concentration of 10 mg L−1 after 16 h.
At the same concentration, products 5c, 6c, 7c, and 8c with iso-propoxy groups reveal
protection effects of 89.8%. As shown in Figure 1, the corrosion rate decreases with re-
duce of concentrations of compounds 5a, 6a, 7a, and 8a less than 10 mg L−1. It is of
interest to compare the inhibition efficiencies of 5a, 6a, 7a, and 8a with long chain S-
alkyl O,O-diethyl dithiophosphates previously obtained by the reaction of O,O-diethyl
dithiophosphoric acid with olefins 1a–c12 by the induction period after addition to the
brine. The protection effect of latest compounds occurs 2–3 h after the introduction of
inhibitor,12 whereas the mixture of 5a, 6a, 7a, and 8a works as inhibitor at 1–1.5 h after
introduction in brine. Thus, the synergistic effect of the mixture of red phosphorus and
sulfur on inhibition efficiency of long chain S-alkyl esters of phosphorus thioacids was
established.

488
I. S. NIZAMOV ET AL.
Table 1 Inhibition coefficients γ and inhibition efficiencies η for different concentrations of compounds 5e, 6e,
7e and 8e at carbonaceous mild steel corrosion
Compounds
Dose, mg L−1
γ (16 h)
η, % (16 h)
5a, 6a, 7a, 8a
5a, 6a, 7a, 8a
5a, 6a, 7a, 8a
5b, 6b, 7b, 8b
5b, 6b, 7b, 8b
5c, 6c, 7c, 8c
5d, 6d, 7d, 8d
5d, 6d, 7d, 8d
5d, 6d, 7d, 8d
5e, 6e, 7e, 8e
5d, 6d, 7d, 8d
10
5
2,5
10
5
10
10
5
12.3
5.5
4.4
1.8
2.0
9.8
6.1
5.3
2.9
5.7
7.1
91.8
82.0
77.1
45.7
50.6
89.8
83.5
81.3
66.0
82.5
85.8
1
10
5
EXPERIMENTAL
The 31P NMR spectra were taken on a Bruker Avance 400 spectrometer (161.98 MHz;
Bruker BioSpin GmbH, Rheinstetten, Germany) in C6H6 with 85% H3PO4 as an external
reference. The 1H NMR spectra were recorded at ambient temperature with a Bruker Avance
400 instrument (400 MHz; Bruker BioSpin GmbH, Rheinstetten, Germany) in CDCl3. The
13C NMR spectra were run with a Bruker Avance-600 spectrometer (100.6 MHz; Bruker
BioSpin GmbH, Rheinstetten, Germany) in CDCl3. Chemical shifts δ are presented in ppm
relative to residual resonance of solvent (1H: 7.26 ppm), coupling constants J are given
in Hz. FTIR spectra were obtained from films with a Bruker Vector 22 (400–4000 сm−1
,
Bruker Optik GmbH, Ettlingen, Germany) and expressed in cm−1, δ = the deformation
Figure 1 Dependences of corrosion rate on time for mild steel in brine (blank) and in brine containing compounds
5e, 6e, 7e, and 8e in concentrations of 10, 5, and 2.5 mg L−1
.

LONG-CHAIN ALKYL THIOPHOSPHATES
489
vibration. The ESI mass spectra were determined on a Bruker Compass Data Analysis 4.0
mass spectrometer (Bruker Daltonik GmbH, Bremen, Germany).
Red phosphorus was purified from residues of white phosphorus by refluxing with
7% aqueous solution of NaOH, washed by anhydrous diethyl ether and benzene and dried
under vacuum (0.02 mm Hg) at 40◦C. Sulfur was dried by refluxing in anhydrous benzene
by means of a Dean-Stark trap. Olefins of industrial fractions of С16–С18 (TU 2411-067-
05766801-97) and С20–С26 (TU 2411-068-05766801-97) were dried with CaCl2.
Corrosion tests were carried out in a 1 L glass cell with three similar mild steel
electrodes Pattern 44–1018MS of 30.7 mm length and 4.7 mm diameter, which were
used in turn during subsequent experiments. Platinum mesh and Ag/AgCl/KCl saturated
electrode (SSE) were used as counter electrode and reference electrode, respectively. The
potential of this reference electrode at 25◦C is 200 mV versus the standard H2 electrode. All
electrode potentials were thus expressed with reference to SSE. Before each experiment,
the working electrodes were treated with abrasive paper (1200 grit SiC), etched with 10%
HCl solution for 10 min, washed with distilled water, then acetone and dried by warm air,
immediately afterwards placed into the cell.
Synthetic brine was used for experiments based on the ASTM D1141–90 standard
(NaCl—24.5; MgCl2—5.2; Na2SO4—4.09: CaCl2—1.16; KCl—0.66; NaHCO3—0.2 g
L
−1). The solution was magnetically stirred at a speed of 500 rpm and carbon dioxide was
bubbled through the solution. Upon the saturation with carbon dioxide, the pH of the brine
was found to be 5.3. Experiments were carried out at 40◦C, the temperature being controlled
within 1◦C. The time of the introduction of electrodes was counted from the point when
the equilibrium distribution of ions and hydrated particles, formed upon dissolution of CO2,
was reached, the equilibrium being controlled via the stability of the pH values.
Field Machine ICM Instruments (ACM Instruments, Cumbria, England) was used
for inhibition efficiency tests, pH values were measured by a pH-meter HI 9025 Hanna
Instruments (Woonsocket, Rhode Island, USA). The corrosion rates were determined by
polarization curves and by means of linear polarization resistance (Rp). Value Rp was
measured after the introduction of electrodes in the cell at an interval of 0.5 h ( 6 mV
respective to corrosion potential, scan rate of the potential being equal to 0.3 mV/s).
Electrochemical impedance spectrum was recorded 16 h after the introduction of inhibitor in
thefrequencyinterval1–30kHzwith10pointsperdecadeatcorrosionpotentialapplyingthe
amplitude of alternating voltage 3 mV. Potentiodynamic polarization curves were recorded
at the end of experiment, in most cases 22 h after the introduction of inhibitor into the brine
in a range of −200 + 30 mV (0.5 cycle) for cathode and a range −30 + 250 mV (1 cycle)
for anode regions respective to corrosion potential with the scan rate of 0.3 mV s−1. The
polarization resistance values were calculated as corrosion rates Ucor (mm y−1), as follows:
bA bC
=
(1)
Ucor
2.3(
+
)
bA bc RP
(t)
where bA and bC—Tafel coefficients determinated graphically from potentiodynamic po-
larization curves; Rp—polarization resistance; t—time after introduction of inhibitor into
the brine.
The inhibition efficiency (η) and inhibition coefficient (γ ) were calculated using the
following equations:
η = 100 (Ucor (0) − Uinh (t)) /Ucor (0)
γ = Ucor (0) /Uinh (t)
(2)
(3)

490
I. S. NIZAMOV ET AL.
where Ucor(0)—corrosion rates without inhibitor; Uinh(t)—corrosion rates in time t after
inhibitor introduction.
S-Alkyl O,O-Di-iso-butyl Dithiophosphates 5a and 6a, and O-Alkyl
O,O-Di-iso-butyl Thionophosphates 7a and 8a
The mixture of red phosphorus (0.4 g), sulfur (0.81 g), and iso-butanol (1.87 g,
25.2 mmol) was heated for 12 h at 100–110◦ with stirring. Olefins 1a–c (3.4 g, 14.3 mmol)
and anhydrous ZnCl2 (0.1 g, 0.7 mmol, 2.9 wt%) were added into the mixture and the
stirring was continued for 4 h at 80◦C. The mixture was filtered. The filtrate was evap-
orated under vacuum (0.02 mm Hg) at 60◦C for 1 h and gave 2.7 g (90%) of a mixture
20
of 5a, 6a, 7a, and 8a. nD 1.4450. Anal. Found С 62.11; Н 11.08, Р 5.86; S 12.59.
С24Н51О2РS2 and С26Н55О2РS2. Calcd. С 61.75–63.10; Н 11.04-311.23; Р 6.26–6.64;
S 12.93–13.71% (there and then elemental analysis data for minor products 7 and 8 were
not taken into account). IR: film, ν = 2957, 2924, 2854 (СН3 as, s; СН2 as, s); 1466
δ (СН3 as); 1377 δ [(СН3)2C gem. s); 999 [(P)O C]; 964 (OC C); 675 (P S); 553
(P S). 1H NMR: δ = 0.86 t (3Нxn, СН3СH2CH2, 3JНH = 7.5 Hz, 7a, 8a); 0.91 t (3Нxn,
3
3
СН3СH2CH2, JНH = 7.2 Hz, 5a, 6a); 1.00 d {12Нxn, [(СН3)2CHCH2О]2Р, JНH
=
6.8 Hz}; 1.29 br s [С(СН2)nС]; 1.39 m [1Нxn, СH(CH3)2]; 1.52 d [3Нxn, СН3С(Н)SP,
3JНH = 6.2 Hz, 6a]; 1.59 s [6Hxn, (СН3)2CSP, 5a]; 1.60 m [2Нxn, PSС(СН3)2СH2CH2,
5a, 7a]; 1.67 m [2Нxn, PSСН(СН3)СH2CH2, 6a]; 1.70 s [6Hxn, (СН3)2CSP, 7a]; 2.00 m
(2Нxn, PSС(СН3)2СH2CH2, 5a, 7a); 2.07 t (2Нxn, PSС(СН3)2СH2CH2, 3JНH = 6.8 Hz,
5a, 7a); 3.03 m [1Нxn, PSСН(СH3)CH2, 6a]; 3.87 m {4Нxn, [(СН3)2CHCH2О]2Р, 5a,
6a}; 3.97 m {4Нxn, [(СН3)2CHCH2О]2Р, 7a, 8a}. The 13C NMR (signal form in the 13C-
{ H} NMR was brought in braces): δ = 14.1 q (s) [(СН3)2CHCH2О, 1JНC = 125.0 Hz, 5a,
1
6a, 7a, 8a]; 15.8 q (s) [(СН3)2CSP, 1JНC = 124.7 Hz, 5a, 7a]; 17.9 q (s) (СН3CHSP, 1JНC
= 124.1 Hz, 6a, 8a]; 18.9 and 19.0 two q (two s) (СН3СH2CH2, 1JНC = 125.5 Hz, 5a, 6a,
7a, 8a); 22.7 t (s) (СН3СH2CH2, 1JНC = 124.1 Hz, 5a, 6a, 7a, 8a); 23.4–23.5, 24.3–24.7,
26.6–26.8 and 27.7–28.0 m (m) (СН2СH2CH2); 28.9 t (s) [PSC(CH3)2СН2СН2СH2CH2,
1JНC = 126.2 Hz, 5a); 29.2 t (s) [PSC(CH3)2СН2СH2CH2, 1JНC = 126.9 Hz, 5a); 29.4 t
(s) (СН3СH2CH2, 1JНC = 123.2 Hz, 5a, 6a, 7a, 8a); 29.6 t (s) (СН3СH2CH2CH2, 1JНC
= 128.4 Hz, 5a, 6a, 7a, 8a); 29.7 t (s) (СН2СH2CH2, 1JНC = 124.7 Hz, 6a, 8a); 31.9 t (s)
( СH2 , 1JНC = 126.2 Hz); 33.9 t (s) (СH2, 1JНC = 129.7 Hz); 36.7 t (s) (POCHСH2, 1JНC
= 120.3 Hz, 7a); 37.7 t (s) (POCСH2, 1JНC = 120.3 Hz, 8a); 39.5 m (s) (PSCHСH2, 6a);
39.8 t (s) (PSCСH2, 1JНC = 126.9 Hz, 5a); 36.7 m (d) (PSСH, 2JPC = 5.9 Hz, 6a); 41.3 m
(d) (PSС, 2JPC = 5.5 Hz, 5a); 67.4 m (s) (POСHCH2CH2, 8a); 70.0 m (s) [POС(CH3)2CH2,
7a]; 73.5 dt (d) [POСH2CH(CH3)2, 1JНC = 170.9 Hz, 2JPC = 7.7 Hz, 7a, 8a]; 73.8 dt (d)
[POСH2CH(CH3)2, 1JНC = 170.2 Hz, 2JPC = 6.6 Hz, 5a, 6a]. 31Р NMR: δР = 98.9, 90.3
and 69.0 in ratio 15:55:30. MS (ESI), m/e: 478.3 [М]+, 501.4 [М + Na]+ require 478.8
7a, 8a (from C18); 554.6 [М + Na + K]+, 1009.6 [2М + K]+ require 466.8 5a, 6a (from
C16); 1049.1 [2М + Na + K]+ requires 494.8 5a, 6a (from C18).
S-Alkyl O,O-Di-iso-octyl Dithiophosphates 5b and 6b and O-Alkyl
O,O-Di-iso-octyl Thionophosphates 7b and 8b
The mixture of red phosphorus (0.79 g), sulfur (1.59 g) and iso-octanol (6.5 g,
49.9 mmol) was heated for 10 h at 100◦C with stirring. Olefins 1a–c (6.1 g, 25.6 mmol)
and anhydrous ZnCl2 (0.15 g, 1.1 mmol, 2.5 wt%) were added into the mixture and the
stirring was continued for 4 h at 80◦C. The mixture was filtered. The filtrate was diluted

LONG-CHAIN ALKYL THIOPHOSPHATES
491
with 10 mL of diethyl ether and washed with three portions of 20 mL of water. The
organic layer was separated and dried with CaCl2 for 1 day. The mixture was filtered.
The filtrate was evaporated at reduced pressure (0.5 mm Hg) at 40◦C for 1 h and then
under vacuum (0.02 mm Hg) at 40◦C for 1 h and gave 7.2 g (96%) of the mixture of
5b, 6b, 7b, and 8b. Anal. Found С 66.49; Н 11.43, Р 5.12; S 10.77. С32Н67О2РS2 and
С34Н71О2РS2. Calcd. С 66.37–67.26; Н 11.70–11.82; Р 5.11–5.35; S 10.55–11.05. IR:
film, ν = 2959, 2955, 2855 (СН3 as, s; СН2 as, s); 1464 δ (СН3 as); 1379 δ (СН3 s);
1038 [(P)O C]; 972 (OC C); 663 (P S); 554, 544 (P S). 1H NMR: δ = 0.86 t (3Нxn,
СН3СH2CH2, 3JНH = 7.5 Hz, 7a, 8a); 0.90 t (3Нxn, СН3СH2CH2, 3JНH = 7.2 Hz, 5b,
6b); 0.93 d {12Нxn, [(СН3)2CH(CH2)4CH2О]2Р, 3JНH = 7.2 Hz}; 1.28 br s [С(СН2)nС];
1.32 m (2Нxn, CH2); 1.38 m [2Нxn, CH2); 1.39 s [6Hxn, (СН3)2CSP, 5b]; 1.41 s [6Hxn,
(СН3)2CSP, 7b]; 1.49–1.69 m (2Нxn, CH2); 1.99 m [1Нxn, (СН3)2CHCH2]; 2.06 dt
3
[2Нxn, PSС(СН3)2СH2CH2, JНH = 6.8 Hz, 5b, 7b]; 3.13 m [1Нxn, PSСН(СH3)CH2,
6b]; 3.97 dt [4Нxn, (CH2CH2О)2Р, 3JНH = 8.5 Hz, 3JPH = 5.1 Hz, 5b, 6b]; 4.05 dt [4Нxn,
(CH2CH2О)2Р, 3JНH = 8.5 Hz, 3JPH = 5.8 Hz, 7b, 8b]. 31Р NMR: δР = 69.7 and 91.0 in
ratio 77:23.
S-Alkyl O,O-Di-iso-propyl Dithiophosphates 5c and 6c and O-Alkyl
O,O-Di-iso-propyl Thionophosphates 7c and 8c
Products 5c, 6c, 7c, and 8c were obtained in analogy to experiment (b) from red
phosphorus (1.0 g), sulfur (2.1 g), iso-propanol (4.0 g, 58.7 mmol), and olefins 1a–c (8.4 g,
35.2 mmol) with use of ZnС12 (0.3 g, 2.2 mmol, 3.6 wt%). Heptane was used instead
of Et2O. Yield 5.1 g (71%). Part of crude products (1.5 g) was chromatographed on a
silica gel (0.060–0.200 micron) column with petroleum ether (bp. 40–70◦C) as eluent,
20
Rf 0.40 (petroleum ether). nD 1.4490. Anal. Found С 61.66; Н 11.06, Р 6.76; S 14.72.
С22Н47О2РS2 and С24Н51О2РS2. Calcd. С 60.23–61.75; Н 10.80–11.04; Р 6.64–7.06; S
13.71–14.62%. 1H NMR: δ = 0.90 t (3Нxn, СН3СH2CH2, 3JНH = 7.2 Hz, 5c, 6c); 0.97
3
t (3Нxn, СН3СH2CH2, JНH = 7.2 Hz, 7c, 8c); 1.28 br s [С(СН2)nС]; 1.36 d {12Нxn,
3
3
[(СН3)2CHО]2Р, JНH = 6.3 Hz}; 1.38 d {12Нxn, [(СН3)2CHО]2Р, JНH = 6.3 Hz};
1.52 s [6Hxn, (СН3)2CSP, 5c]; 1.53–1.69 m (2Нxn, CH2); 1.60 s [6Hxn, (СН3)2CSP, 7c];
1.62 d [3Нxn, СН3С(Н)SP, 3JНH = 6.8 Hz, 6c]; 1.99 t [2Нxn, PSС(СН3)2СH2CH2, 3JНH
= 6.8 Hz, 5c, 7c); 2.06 m [4Нxn, CH2CH2); 3.33 and 3.49 two m [1Нxn, PSСН(СH3)CH2,
6c]; 4.03 and 4.12 two m [1Нxn, POСН(СH3)CH2, 8c]; 4.90 m {2Нxn, [(СН3)2CHО]2Р}.
31Р NMR: δР = 92.9, 87.0 and 64.1 in ratio 7:90:3.
S-Alkyl O,O-Di-iso-octyl Dithiophosphates 5d and 6d and O-Alkyl
O,O-Di-iso-octyl Thionophosphates 7d and 8d
Products 5d, 6d, 7d, and 8d were obtained in analogy to experiment (b) from
red phosphorus (4.0 g), sulfur (0.83 g), iso-octanol (3.36 g, 25.8 mmol), and olefins
2a–c (4.0 g, 12.4 mmol) with use of ZnС12 (0.1 g, 0.7 mmol, 2.5 wt%). Yield 2.6 g
20
(60%). nD 1.4540. Anal. Found С 70.01; Н 12.02, Р 4.75; S 8.99. С35Н75О2РS2,
С38Н79О2РS2, С40Н83О2РS2 and С42Н87О2РS2. Calcd. С 68.07–70.11; Н 11.94–12.22;
Р 4.31–4.88; S 8.90–10.07%. IR: film, ν = 2957, 2924, 2853 (СН3 as, s; СН2 as, s); 1464
δ (СН3 as); 1378 δ (СН3 s); 1035 [(P)O C]; 966 (OC C); 673 (P S); 541 (P S).
3
1H NMR: δ = 0.90 t (3Нxn, СН3СH2СH2, JНH 6.9 Hz, 5d, 6d); 0.92 d {12Нxn,
[(СН3)2CH(CH2)4CH2О]2Р, 3JНH = 7.8 Hz}; 1.04 t (3Нxn, СН3СH2CH2, 3JНH = 8.0 Hz,

492
I. S. NIZAMOV ET AL.
7d, 8d); 1.28 br s [С(СН2)nС]; 1.42 m (2Нxn, CH2); 1.50 s [6Hxn, (СН3)2CSP, 5d]; 1.59 s
3
[6Hxn, (СН3)2CSP, 7d]; 1.60 d [3Нxn, СН3С(Н)SP, JНH = 7.3 Hz, 6d]; 1.65–1.80 m
(2Нxn, CH2); 2.02 m (2Нxn, PSСН(СН3)СH2CH2, 6d); 3.14 m [1Нxn, PSСН(СH3)CH2,
6d]; 3.96 and 4.09 two m [4Нxn, (CH2CH2О)2Р]; 4.26 m [1Нxn, POСН(СH3)CH2, 8d].
31Р NMR: δР = 91.0 and 69.9 in ratio 2:1.
S-Alkyl O,O-Di-iso-butyl Dithiophosphates 5e and 6e and O-Alkyl
O,O-Di-iso-butyl Thionophosphates 7e and 8e
Products 5e, 6e, 7e, and 8e were obtained in analogy to experiment (b) from red
phosphorus (0.4 g), sulfur (0.83 g), iso-butanol (1.9 g, 25.6 mmol), and olefins 2a–c (4.1 g,
20
12.7 mmol) with use of ZnС12 (0.1 g, 0.7 mmol, 2.4 wt%). Yield 2.1 g (58%), nD
1.4610. Anal. Found С 67.14; Н 11.66, Р 5.18; S 10.29. С28Н59О2РS2, С30Н63О2РS2,
С32Н67О2РS2 and С34Н71О2РS2. Calcd. С 64.32–67.27; Н 11.37–11.79; Р 5.10–5.92;
1
3
S 10.56–12.27%. H NMR: δ = 0.90 t (3Нxn, СН3СH2CH2, JНH = 6.9 Hz, 5e, 6e);
3
0.98 d {12Нxn, [(СН3)2CHCH2О]2Р, JНH = 6.4 Hz}; 1.04 t (3Нxn, СН3СH2CH2,
3JНH = 7.8 Hz, 7e, 8e); 1.28 br s [С(СН2)nС]; 1.43 m [(СН3)2CH]; 1.51 s [6Hxn,
(СН3)2CSP, 5e]; 1.60 s [6Hxn, (СН3)2CSP, 7e]; 1.59–1.74 m (2Нxn, CH2); 2.02 dt [2Нxn,
PSСН(СН3)СH2CH2, 3JНH = 6.9 Hz, 6e]; 3.02 m [1Нxn, PSСН(СH3)CH2, 6e]; 3.85 and
3.95 two m {4Нxn, [(СН3)2CHCH2О]2Р}; 4.05 m [1Нxn, POСН(СH3)CH2, 8e]. 31Р
NMR: δР = 91.0 and 69.6 in ratio 9:1.
FUNDING
The study was performed with financial support of the Russian Foundation for Basic
Researches (grant no. 13-03-97043-а).
REFERENCES
1. Pournourmohammadi, S.; Farzami, B.; Ostad, S. N.; Azizi, E.; Abdollahi, M. Environ. Toxicol.
Pharmacol. 2005, 19, 191-196.
2. Xie, Q.-L.; Sha Y.-L. Chinese J. Chem. 1994, 12, 449-455.
3. Cherkasov, R. A.; Sofronov, A. V.; Martianov, Y. M.; Nizamov, I. S.; Terenzhev, D. A. Phos-
phorus Sulfur Silicon Relat. Elem. 2011, 186, 1003-1004.
4. Sofronov, A. V.; Nizamov, I. S.; Almetkina, L. A.; Nikitina, L. E.; Fatyhova, D. G.; Zelenikhin,
P. V.; Il’inskaya, O. N.; Cherkasov, R. A. Russ. J. Gen. Chem. Eng. Tr. 2010, 80, 1267-1271.
5. Mohsin, M.; Nagar, M.; Choudhary, A. Phosphorus Sulfur Silicon Relat. Elem. 2012, 187,
1331-1338.
6. Barnes, A. M.; Bartle, K. D.; Thio, A. Tribol. Int. 2001, 34, 389-395.
7. Drake, J. E.; MacDonald, C. L. B.; Kumar, A.; Pandey, S. K.; Ratnani, R. J. Chem. Crystallogr.
2005, 35, 447-450.
8. Kumar, A.; Kumar, K.; Pandey, S. K. Polish J. Chem. 2009, 83, 2097-2104.
9. Drake, J. E.; Gurnani, C.; Hursthouse, M. B.; Light, M. E.; Nirwan, M.; Ratnani, R. Appl.
Organomet. Chem. 2007, 21, 539-544.
10. Singh, O.; Saini, M. S.; Dwivedi, J., Kumar, A. Phosphorus Sulfur Silicon Relat. Elem. 2012,
187, 1324-1330.
11. Pudovik, S. T., Kadyrova, A. R.; Kachalova, T. N.; Kharlampidi, Kh. E. RF Patent 2243253,
Bull. Izobr. Russ. 2004, 16.

LONG-CHAIN ALKYL THIOPHOSPHATES
493
12. Nizamov, I. S.; Popovich, Ya. Ye.; Sergeenko, G. G.; Batyeva, E. S.; Alfonsov, V. A.; Galiakberov,
R. M.; Khodyrev, Yu. P.; Magdeev, I. M.; Yakubov, M. R.; Sinyashin, O. G. RF Patent 2337913,
Bull. Izodr. Russ. 2008, 3.
13. Khodyrev, Yu. P.; Batyeva, E. S.; Badeeva, E. K.; Platova, E. V.; Tiwari, L.; Sinyashin, O. G.
Corros. Sci. 2011, 53, 976-983.
14. Nizamov, I. S.; Popovich, Ya. Ye.; Nizamov, I. D.; Cherkasov, R. A. Zh. Obsch. Khim. (Russ).
2008, 78, 1051-1052.
15. Nizamov, I. S.; Nizamov, I. D.; Popovich, Y. Y.; Cherkasov, R. A. Zh. Obsch. Khim. (Russ).
2012, 82, 30-35.
16. Kursheva, L. I.; Nizamov, I. S.; Batyeva, E. S.; Nizamov I. D.; Yambushev F. D.; Cherkasov, R.
A. Phosphorus Sulfur Silicon Relat. Elem. 2013, 188, 487-489.
17. Hoffmann, H.; Becke-Goehring, M. Topics in Phosphorus Chemistry. In: E. J. Griffith; M.
Grayson (Ed.), Phosphorus Sulfides, Vol. 8; John Wiley and Sons, Inc.: New York, London, 220
Sydney, Toronto, 1976; pp. 193-271.
18. Sinyashin, O. G.; Batyeva, E. S.; Ugryumov, O. V.; Nizamov, I. S.; Varnavskaya, O. A.; Vasyukov,
S. I.; Khodyrev, Yu. P.; Platova, E. V.; Badeeva, E. K.; Kursheva, L. I. Phosphorus Sulfur Silicon
Relat. Elem. 2013, 188, 21-23.
19. Nizamov, I. S.; Yermolaev, Ye. S.; Nizamov, I. D.; Sergeenko, G. G.; Batyeva, E. S.; Alfonsov,
V. A. Chem. Techn.: An Indian J. 2007, 2, http://tsijournals.com/ctaij/Vol 2 3/Abs08.html.
20. Mazitova, F. N.; Khairullin, V. K. Zh. Obsch. Khim. (Russ). 1980, 50, 1718-1722.
21. Crutchfield, M. M.; Dungan, C. H.; Letcher, J. H.; Mark, V.; VanWazer, J. R. Topics in Phosphorus
Chemistry. In: M. Grayson; E. J. Griffith (Ed.), 31P Nuclear Magnetic Resonance, Vol. 5; John
Wiley and Sons: New York, 1967; pp. 492.
22. Hoffmann, H.; Becke-Goehring, M. Topics in Phosphorus Chemistry. In: E. J. Griffith; M.
Grayson (Ed.), Phosphorus Sulfides. Vol. 8; John Wiley and Sons: New York, 1976; p. 193-271.
23. Nizamov, I. S.; Popovich, Ya. Ye.; Nizamov, I. D.; Khodyrev, Yu. P.; Batyeva, E. S.; Sinyashin,
O. G. RF Patent 2449056 Bull. Izodr. Russ. 2012, 12.
24. Mora-Mendoza, J. L.; Turgoose, S. Corros. Sci. 2002, 44, 1223-1246.
25. Carvalho, D. S.; Joia, C. J. B.; Mattos, O. R. Corros. Sci. 2005, 47, 2974-2986.

Copyright of Phosphorus, Sulfur & Silicon & the Related Elements is the property of Taylor
& Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a
listserv without the copyright holder's express written permission. However, users may print,
download, or email articles for individual use.