Synthesis of new secondary phosphine chalcogenides with bulky substituents from aryl(hetaryl)ethenes, red phosphorus, sulfur, and selenium

Article abstract of DOI:10.1134/S1070363209080052

Phosphine generated along with hydrogen from red phosphorus and aqueous potassium hydroxide selectively reacts with aryl(hetaryl)ethenes (α-methylstyrene, 2-vinylnaphthalene and 5-vinyl-2-methylpyridine) in superbasic system KOH-DMSO(H₂O) to give secondary phosphines. The latter are practically quantitatively oxidized by elemental sulfur or selenium (20-25°C, toluene, 0.5 h), to afford the hitherto unknown secondary phosphine chalcogenides with bulky arylalkyl pyridine and naphthyl substituents.

Full text of DOI:10.1134/S1070363209080052

ISSN 1070-3632, Russian Journal of General Chemistry, 2009, Vol. 79, No. 8, pp. 1617–1621. © Pleiades Publishing, Ltd., 2009.
Original Russian Text © S.F. Malysheva, A.V. Artem’ev, N.K. Gusarova, B.V. Timokhin, A.A. Tatarinova, B.A. Trofimov, 2009, published in Zhurnal
Obshchei Khimii, 2009, Vol. 79, No. 8, pp. 1259–1263.
Synthesis of New Secondary Phosphine Chalcogenides
with Bulky Substituents from Aryl(hetaryl)ethenes,
Red Phosphorus, Sulfur, and Selenium
S. F. Malysheva, A. V. Artem’ev, N. K. Gusarova,
B. V. Timokhin, A. A. Tatarinova, and B. A. Trofimov
Favorskii Irkutsk Institute of Chemistry, Siberian Branch, Russian Academy of Sciences,
ul. Favorskogo 1, Irkutsk, 664033 Russia
e-mail: gusarova@irioch.irk.ru
Received Februaty 24, 2009
Abstract—Phosphine generated along with hydrogen from red phosphorus and aqueous potassium hydroxide
selectively reacts with aryl(hetaryl)ethenes (α-methylstyrene, 2-vinylnaphthalene and 5-vinyl-2-
methylpyridine) in superbasic system KOH–DMSO(H2O) to give secondary phosphines. The latter are
practically quantitatively oxidized by elemental sulfur or selenium (20–25оС, toluene, 0.5 h), to afford the
hitherto unknown secondary phosphine chalcogenides with bulky arylalkyl pyridine and naphthyl substituents.
DOI: 10.1134/S1070363209080052
Secondary phosphine chalcogenides R2P(X)H (X =
O, S, Se) due to their ability to exist in a tautomeric
form R2P–XH are effective chemolabile ligands in
metal complex catalysis [1, 2] of the cross-coupling
reactions of Tamao–Kumada–Corriu [3], Suzuki-
Miyaura [4], Heck, Stiles [5], Sonogashira [6], Negishi
[7]). An advantage of hydrochalcogenophosphoryl
compounds as ligands in comparison with the
conventionally used phosphines is their higher
oxidative stability [3]. In the last years the phosphine
chalcogenide ligands with sterically bulky substituents
were also successfully used for the design of metal
complex catalysts. For example, di(tert-butyl)phos-
phine chalcogenides t-Bu2P(X)H (X = O, S) in
conbination with bis(cyclooctadienyl)nickel Ni(COD)2
effectively catalyze the Tamao-Kumada-Corriu
reaction of arylchlorides with arylmagnesium halides
[8]. However, as a rule, the synthesis of these
phosphine chalcogenide ligands is laborious, multi-
step and ecologically hardly acceptable since it is
based on the reactions of toxic and aggressive phos-
phorus halides with organometal compounds.
phine PH3 to weakly electrophilic alkenes (arylethenes,
vinylpyridines, vinylnaphthalenes) with further oxida-
tion of the secondary phosphines with elemental
chalcogenes. Phosphine is generated together with
hydrogen (in ~1:1 volume ratio) from red phosphorus
and potassium hydroxide in water–toluene medium in
a separate flask [14].
In this paper, this effective approach is used for
directed synthesis of new sterically hindered secondary
phosphine sulfides and phosphine selenides based on
hydrophosphination of α-methyl-styrene, 2-vinyl-
naphthalene and 5-vinyl-2-methylpyridine.
For example, the secondary bis(2-phenylpropyl)
phosphine selenide was prepared by Scheme 1 includ-
ing the reaction of red phosphorus with KOH in water–
toluene medium at 70–80°С, hydrophosphination of α-
methylstyrene with phosphine in a superbasic system
KOH–DMSO at 70–75°С with formation of the
intermediate secondary phosphine I and subsequent
oxidation of the latter (without isolation and purifica-
tion) with elemental selenium in toluene at room
temperature. The yield of phosphine selenide II was
82% (here and hereinafter the yield is calculated on the
starting alkene).
Recently, a new general convenient approach to the
synthesis of secondary phosphine chalcogenides has
been developed [9–13]. The approach is based on the
selective reaction of nucleophilic addition of phos-
Similarly, according to Scheme 2, from 2-vinyl-
naphthalene, elemental phosphorus, and sulfur or
1617

1618
MALYSHEVA et al.
Scheme 1.
Me
Me
KOH/H2O
Pn
PH3/H2
P
H
PhMe, 70_80oC
KOH/DMSO (H2O),
70_75oC
Me
I
Me
Se
H
Se
P
PhMe, 20_25oC
Me
II
Scheme 2.
KOH/H2O
P
H
Pn
PH3/H2
PhMe, 70_80oC
KOH/DMSO (H2O),
70_75oC
III
X
H
S8 (Se)
P
PhMe, 20_25oC
IV, V
X = S (IV), Se (V).
selenium, secondary phosphine sulfide IV and
phosphine selenide V with bulky naphthyl substituents
were prepared in 88 and 87% yield, respectively.
methylstyrene and 2-vinylnaphthalene (Schemes 1 and
2), that can be explained by higher electrophilicity of
the double bond of 5-vinyl-2-methylpyridine.
On the example of 5-vinyl-2-methylpyridine it was
shown that the developed procedure can be suc-
cessfully applied for the synthesis of new secondary
phosphine chalcogenides VII, VIII with bulky hetaryl-
alkyl substituents (Scheme 3).
Therefore, the hitherto unknown secondary phos-
phine chalcogenides containing bulky 2-phenylpropyl,
2-(2-naphthyl)ethyl and 2-(2-methylpyrid-5-yl)ethyl
fragments were synthesized in high yield from
available reagents: red phosphorus, KOH, α-methyl-
styrene, 2-vinylnaphthalene, 5-vinyl-2-methylpyridine,
elemental sulfur and selenium. The obtained secondary
phosphine chalcogenides are promising chemolabile
ligands for design of metal complex catalysts as well
as suitable models for investigation of the diad
prototropic tautomerism [15] and reactive synthons for
The yield of secondary phosphine chalcogenides
VII, VIII calculated on 5-vinyl-2-methyl-pyridine was
86 and 81%, respectively. Note, that nucleophilic
addition of phosphine РН3 to 5-vinyl-2-methylpyridine
proceeds under milder conditions (45–50°С , KOH–
DMSO) as compared to hydrophosphination of α-
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SYNTHESIS OF NEW SECONDARY PHOSPHINE CHALCOGENIDES
1619
Scheme 3.
Me
N
Me
N
KOH/H2O
P
H
Pn
PH3/H2
PhMe, 70_80oC
KOH/DMSO (H2O),
45_50oC
N
Me
VI
Me
N
N
X
H
S8 (Se)
PhMe, 20_25oC
P
Me
VII, VIII
X = S (VII), Se (VIII).
atom-saving synthesis of the tertiary phosphine
chalcogenides on demand [16–20] based on the
reactions of nucleophilic and radical addition of these
РН-addends to multiple bonds (C=C, C≡C, C=O).
H2O flushed with argon and saturated with phosphine–
hydrogen mixture 7.0 g of α-methylstyrene in 10 ml
DMSO was added dropwise at 70–75°С in the course
of 1.5 h upon continuous bubbling of phosphine. The
supply of phosphine was stopped, another 3.0 g of α-
methylstyrene was added and stirring at this
temperature was continued for 30 min, then the reac-
tion mixture was cooled, diluted with water (100 ml),
extracted with toluene (100 ml), toluene extracts were
washed with water (30 ml×3), dried over potassium
carbonate, 3.34 g of amorphous selenium was added.
The obtained suspension was stirred at room
temperature for 30 min, filtered, solvent was removed,
the residue washed with hexane (5 ml×2). 12.11 g
(82%) of phosphine selenide II was obtained as a
white powder, mp 94–96ºС (hexane). IR spectrum
(KBr), cm–1: 3103, 3083, 3061, 2026, 3000, 2959,
2925, 2899, 2869, 2726, 2350, 1948, 1874, 1806,
1751, 1673, 1602, 1583, 1544, 1493, 1453, 1399,
1375, 1358, 1326, 1314, 1305, 1285, 1235, 1196,
1174, 1155, 1089, 1054, 1029, 1011, 997, 934, 914,
881, 846, 819, 804, 763, 699, 663, 620, 579, 555, 542,
Besides, in the present work the method of
synthesis of the intermediate secondary phosphines
was improved. The increase of the basicity of the
system KOH–DMSO–H2O at the stage of
hydrophosphination of the corresponding alkenes
allowed to increase the yields of phosphines I, III, and
VI with respect to those earlier obtained by 19% [21],
13% [22] and 13% [23], respectively.
EXPERIMENTAL
IR spectra were recorded on a Bruker IFS-25 in thin
1
layer and in KBr pellets. Н, 13С, 31Р and 77Se NMR
spectra were registered on a Bruker DPX 400
spectrometer (400.13, 101.61, 161.98 and 76.31 MHz,
13
respectively), with HMDS (1H, C) and Me2Se (77Se)
as internal standards and 85% Н3РО4 as an external
standard (31Р). All experiments were carried out in an
inert atmosphere (argon). α-Methylstyrene and 5-vinyl-
2-methylpyridine were distilled prior to use. 2-Vinyl-
naphthalene was purified by sublimation under
reduced pressure. Phosphine–hydrogen mixture was
prepared in a separate flask by adding 50% aqueous
solution of KOH (50 g) to the mixture of 20 g of red
phosphorus and 50 ml of toluene at 70–80°С .
1
531, 491, 440. Н NMR spectrum (CDCl3), δ, ppm (J,
Hz): 1.23–1.33 m (6H, Me), 2.02-2.33 m (4H, CH2P),
3.19–3.37 m (2H, CH), 5.22 d (PH, 1JPH 439.3), 5.49 d
(PH, 1JPH 439.6), 5.87 d (PH, 1JPH 437.7), 7.12–7.30 m
(10H, Ph). 13С NMR spectrum (CDCl3), δС, ppm:
22.12 d (Ме 2JPC2 16.1 Hz), 22.21 d (Ме, 2JPC 16.4 Hz),
23.67 d (Ме, JPC 13.5 Hz), 34.62 (СНРh), 35.07
1
(СНРh), 35.34 (СНРh), 36.74 d (CH2P, JPC 78.0 Hz),
Bis(2-phenylpropyl)phosphine selenide (II). To
suspension of 20 g KOH in 50 ml DMSO and 3 ml
37.18 d (CH2P, 1JPC1 78.0 Hz), 38.09 d (CH2P, 1JPC 74.2 Hz),
38.17 d (CH2P, JPC 76.3 Hz), 126.46 (C-р), 126.52
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 79 No. 8 2009

1620
MALYSHEVA et al.
3
and 126.58 (С-о), 143.39 (C-i, JPC3 19.4 Hz), 143.44
2.38–2.49 m (2H, CH2Р), 2.99–3.28 m (4H,
(C-i, JPC 20.4 Hz), 144.59 (C-i, JPC 16.1 Hz). 31Р
CH2Naph), 6.00 d (1Н, РН, JРН 433.8), 7.13–7.82 m
3
1
NMR spectrum (CDCl3), δР, ppm: –4.43, –3.75,
–2.49 (the ratio of intensities is 13 : 20 : 10). The
presence of the three signals in the 31P NMR spectrum
can be due to the presence of three asymmetric centers
in the molecule. 77Se NMR spectrum (CDCl3), δSe,
ppm: –427.54 d (1JPSe 730.0 Hz), –420.96 d (1JPSe
729.6 Hz), –498.36 d (1JPSe 727.5 Hz). Found, %: С
61.55; Н 6.61; Р 8.40; Se 22.96. С18Н23РSe.
Calculated, %: С 61.89; Н 6.64; Р 8.87; Se 22.60.
(14H, Naph). 13С NMR spectrum (CDCl3), δС, ppm:
1
29.86 d (CH2Naph, 2JPC 2.9 Hz), 30.62 d (CH2P, JPC
43.5 Hz), 125.79, 126.35, 126.68, 126.80, 127.59,
127.71, 128.58, 132.32, 133.53, 136.84, 136.92,
137.04 (Naph). 31Р NMR spectrum (CDCl3), δР, ppm:
77
2.27 (1JPSe 710 Hz). Se NMR spectrum (CDCl3), δSe,
ppm: –414.07 d (1JPSe 710 Hz). Found, %: С 68.35; Н
5.61; Р 7.40; Se 18.96. С24Н23РSe. Calculated, %: С
68.41; Н 5.50; Р 7.35; Se 18.74.
Synthesis of phosphine chalcogenides (IV, V). To
suspension of 20 g KOH in 45 ml DMSO and 4.5 ml
H2O flushed with argon and saturated with phosphine–
hydrogen mixture the solution of 3.0 g of 2-vinyl-
naphthalene in 20 ml DMSO was added dropwise at
70–75°С in the course of 1.5 h upon continuous
bubbling of phosphine. The supply of phosphine was
stopped, the mixture was stirred at this temperature for
30 min, then cooled, diluted with water (100 ml),
extracted with toluene (100 ml), toluene extracts were
washed with water (30 ml×3), dried over potassium
carbonate, 0.31 g of elemental sulfur or 0.77 g of
selenium was added. The suspension was stirred at
room tem-perature for 30 min, filtered, the solvent was
removed under a reduced pressure, the residue washed
with hexane (5 ml×2).
Synthesis of phosphine chalcogenides (VII, VIII).
To suspension of 20 g KOH in 50 ml DMSO and 6 ml
H2O flushed with argon and saturated with phosphine–
hydrogen mixture the solution of 10.0 g of 5-vinyl-2-
methylpyridine in 10 ml DMSO was added dropwise at
45–50°С in the course of 2 h upon continuous
bubbling of phosphine. The supply of phosphine was
stopped, the mixture was stirred at this temperature for
30 min, then cooled, diluted with water (100 ml),
extracted with diethyl ether (70 ml×3), the extract were
washed with water (30 ml×3), dried over potassium
carbonate, 1.35 g of elemental sulfur or 3.31 g of
selenium was added. The suspension was stirred at
room temperature for 30 min, filtered, the solvent was
removed under a reduced pressure, the residue was
washed with hexane (5 ml×2).
Bis[2-(2-naphthyl)ethyl]phosphine sulfide (IV).
Yield 3.22 g (88%), yellow powder, mp 99–101ºС
(ether). IR spectrum (KBr), cm–1: 3050, 3017, 2924,
2854, 2325, 1918, 1803, 1675, 1628, 1597, 1508,
1467, 1428, 1396, 1367, 1324, 1285, 1271, 1198,
1154, 1143, 1123, 1013, 963, 948, 899, 857, 815, 763,
Bis[2-(2-methylpyrid-5-yl)ethyl]phosphine sulfide
(VII). Yield 11.00 g (86%), white crystalline powder,
mp 103–105ºС. IR spectrum (KBr), cm–1: 3444. 3096,
3029, 3006, 2919, 2855, 2354, 1639, 1601, 1568,
1491, 1445, 1402, 1334, 1300, 1247, 1213, 1197,
1147, 1029, 1017, 969, 952, 930, 910, 865, 836, 789,
764, 755, 739, 729, 714, 646, 616, 562, 542, 489, 411.
1Н NMR spectrum (CDCl3), δ, ppm (J, Hz): 2.07–2.40
m (4H, CH2Р), 2.52 s (6H, Me), 2.90–3.26 m (4H,
1
739, 643, 630, 620, 600, 533, 476. Н NMR spectrum
(CDCl3), δ, ppm (J, Hz): 2.14–2.29 m (2H, CH2Р),
2.43–2.50 m (2H, CH2Р), 3.01–3.24 m (4H,
1
1
CH2Nаph), 6.05 d (1Н, РН, JРН 440.9), 7.16–7.76 m
CH2Py), 6.51 d (1Н, РН, JРН 441.8), 7.10 d (2Н,
(14H, Naph). 13С NMR spectrum (CDCl3), δС, ppm:
CH=С–Me, 3JHН 8.1), 7.46-7.48 m (2Н, CH=С), 8.39 d
1
4
29.02 (CH2Naph), 31.75 d (CH2P, JPC 50.3 Hz),
(2Н, CH=N, JHН 1.8). 13С NMR spectrum (CDCl3),
125.67, 163.32, 126.68, 127.57, 127.70, 128.46,
128.54, 132.29, 133.53, 137.16, 137.48, 137.65
(Naph). 31Р NMR spectrum (CDCl3), δР, ppm: 20.22.
Found, %: С 76.85; Н 6.14; Р 8.35; S 8.61. С24Н23РS.
Calculated, %: С 76.98; Н 6.19; Р 8.27; S 8.56.
δС, ppm: 23.91 (Ме), 25.74 (CH2Py), 31.47 d (CH2P,
1JPC 50.4 Hz), 123.33 (HС=CMe), 132.13 d
3
(CCH2CH2P, JPC 12.6 Hz), 136.60 (CH=С), 148.70
(HС=N), 156.77 (CMe). 31Р NMR spectrum (CDCl3),
δР, ppm: 20.17. Found, %: C 63.20; H 7.10; P 10.20; S
10.46. C16H21N2PS. Calculated, %: C 63.13; H 6.95; P
10.18; S 10.53.
Bis[2-(2-naphthyl)ethyl]phosphine selenide (V).
Yield 3.58 g (87%), yellow-brown oil. IR spectrum,
cm–1: 3051, 3021, 2925, 2858, 2334, 1952, 1804, 1631,
1599, 1508, 1445, 1367, 1271, 1124, 1018, 996, 950,
Bis[2-(2-methylpyrid-5-yl)ethyl]phosphine sele-
nide (VIII). Yield 11.94 g (81%), yellowish-grey
powder, mp 91–92ºС (hexane). IR spectrum (KBr),
cm–1: 3432, 3098, 3028, 3004, 2919, 2854, 2354, 2344,
1
892, 858, 819, 796, 746, 476. Н NMR spectrum
(CDCl3), δ, ppm (J, Hz): 2.28–2.35 m (2H, CH2Р),
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SYNTHESIS OF NEW SECONDARY PHOSPHINE CHALCOGENIDES
1621
and Trofimov, B.A., J. Struct. Chem., 2005, vol. 46,
no. 6, p. 1066.
11. Gusarova, N.K., Bogdanova, M.V., Ivanova, N.I.,
Сhernysheva, N.А., Sukhov, B.G., Sinegovskaya, L.M.,
Kazheva, O.N., Alexandrov, G.G., D’yachenko, O.A.,
and Trofimov, B.A., Synthesis, 2005, no. 18, p. 3103.
1601, 1567, 1491, 1443, 1400, 1368, 1332, 1300,
1247, 1212, 1195, 1147, 1122, 1030, 1014, 971, 949,
929, 890, 847, 833, 783, 763, 750, 729, 645, 542, 501,
1
489, 466, 410. Н NMR spectrum (CDCl3), δ, ppm (J,
Hz): 2.17–2.33 m (2H, CH2Р), 2.40–2.49 m (2H,
CH2Р), 2.52 s (6H, Ме), 2.91-3.27 m (4H, CH2Py)
1
12. Trofimov, B.A., Sukhov, B.G., Malysheva, S.F., and
Gusarova, N.K., Kataliz v Promyshlennosti, 2006, no. 4,
p. 18.
6.05 d (1Н, РН, JРН 432.7), 7.11 d (2Н, CH=С–Me,
3JHН 7.75), 7.48–7.51 m (2Н, CH=С), 8.41 d (2Н,
4
CH=N, JHН 1.9). 13С NMR spectrum (CDCl3), δС,
1
13. Gusarova, N.K., Malysheva, S.F., Kuimov, V.A.,
Belogorlova, N.A., Mikhailenko, V.L., and Trofi-
mov, B.A., Mendeleev Commun., 2008, vol. 18, no. 5,
p. 260.
14. Gusarova, N.K., Malysheva, S.F., Arbuzova, S.N.,
Brandsma, L., and Trofimov, B.A., Zh. Obshch. Khim.,
1994, vol. 64, no. 12, p. 2062.
15. Kabachnik, M.I., Khimiya i primenenie fosforor-
ganicheskikh soedinenii (Chemistry and Application of
Organophosphorus Compounds), Мoscow: Akad. Nauk
SSSR, 1957, p. 18.
ppm: 23.84 (Me), 26.54 (CH2Py), 30.19 d (CH2P, JPC
43.8 Hz), 123.39 (HС=CMe), 131.98 d (CCH2CH2P,
3JPC 12.8 Hz), 136.77 s (CH=С), 148.62 (HС=N),
156.72 (CMe). 31Р NMR spectrum (CDCl3), δР, ppm:
77
2.24 (1JPSe 718 Hz). Se NMR spectrum (CDCl3), δSe,
ppm: –216.63 d (1JPSe 718 Hz). Found, %: C 54.74; H
6.12; P 8.91; Se 22.50. C16H21N2PSe. Calculated, %: C
54.71; H 6.03; P 8.82; Se 22.48.
ACKNOWLEDGMENTS
16. Aladzheva, I.M., Odinets, I.L., Petrovskii, P.V.,
Mastryukova, T.A., and Kabachnik, M.I., Zh. Obshch.
Khim., 1993, vol. 63, no. 3, p. 611.
This work was performed with a financial support
from the Russian Foundation for Basic Research (grant
nos. 7-03-00562 and 08-03-00251).
17. Arbuzova, S.N., Gusarova, N.K., and Trofimov, B.A.,
Arkivoc, 2006, no. 5, p. 12.
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RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 79 No. 8 2009