Reaction of vinyl selenides with secondary phosphines and elemental selenium: One-pot selective synthesis of a new family of diselenophosphinic se-esters

Article abstract of DOI:10.1002/hc.21144

Alkyl vinyl selenides react with diverse secondary phosphines and elemental selenium in a 1.1:1:2 molar ratio (120-124°C, 20-40 min, 1,4-dioxane) to afford selectively earlier unknown diselenophosphinic Se-esters, R ₂P(Se)SeCH(Me)SeR, in 82-99%

Full text of DOI:10.1002/hc.21144

Heteroatom Chemistry
Volume 00, Number 00, 2014
Reaction of Vinyl Selenides with Secondary
Phosphines and Elemental Selenium: One-Pot
Selective Synthesis of a New Family of
Diselenophosphinic Se-Esters
Alexander V. Artem’ev,1 Nataliya A. Chernysheva,1
Nina K. Gusarova,1 Svetlana V. Yas’ko,1 Jian-Hong Liao,2 C. W. Liu,2
Alexander I. Albanov,1 and Boris A. Trofimov1
1A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of
Sciences, 664033, Irkutsk, Russian Federation
2Department of Chemistry, National Dong Hwa University, Hualien, Taiwan 97401, Republic of
China
Received 7 November 2013; revised 16 January 2014
INTRODUCTION
ABSTRACT: Alkyl vinyl selenides react with di-
verse secondary phosphines and elemental selenium
in a 1.1:1:2 molar ratio (120–124°C, 20–40 min, 1,4-
dioxane) to afford selectively earlier unknown dise-
lenophosphinic Se-esters, R2P(Se)SeCH(Me)SeR´, in
82–99% yield. This three-component atom-economic
reaction proceeds via intermediate formation of dise-
lenophosphinic acid R2P(Se)SeH (generated from sec-
ondary phosphine and selenium), which adds to the
double bond of vinyl selenide in a Markovnikov man-
S-Esters of dithiophosphinic acids, R2P(S)SR’ (R,
R’ = organic groups), represent a well-known and
exhaustively investigated family of chalcogenophos-
phorus compounds [1]. At the same time, their sele-
nium analogues, i.e., diselenophosphinic Se-esters,
are poorly studied, although they are of great the-
oretical and practical interest in light of the high
biological activity of selenium compounds [2]. Fur-
thermore, recently it has been shown that the dise-
lenophosphinic Se-esters are iniferter agents for liv-
ing free radical polymerization of styrene [3]. Among
related compounds, diselenophosphonic Se-esters
are successfully employed for hydroselenophospho-
rylation of alkenes leading to optically active se-
lenophosphonic O,Oꢁ-esters [4].
ꢀC
ner to give the target products.
2014 Wiley Peri-
odicals, Inc. Heteroatom Chem. 00:1–5, 2014; View
this article online at wileyonlinelibrary.com. DOI
10.1002/hc.21144
As for the synthesis of diselenophosphinic Se-
esters [5] and their -phosphate [6] or -phosphonate
congeners [7], the most conventional method is
the reaction between organic halides and the salts
of [R2PSe2]Cat type (R = organic groups, RO
or R2N; Cat = metal or ammonium). Alterna-
tively, such Se-esters can be assembled by con-
densation of selenophosphinic chlorides, R2P(Se)Cl,
with metal alkyl- or arylselenolates [3]. Meanwhile,
these approaches do not always lead to functional
Correspondence to: B. A. Trofimov; e-mail: boris-trofimov
@irioch.irk.ru.
Contract grant sponsor: Russian Foundation for Basic Re-
search.
Contract grant number: 11-03 00334-а.
Contract grant sponsor: President of the Russian Federation
(Program for the Support of Leading Scientific Schools).
Contract grant number: NSh-1550.2012.3.
Supporting Information is available in the online issue at
wileyonlinelibrary.com.
ꢀC
2014 Wiley Periodicals, Inc.
1

2
Artem’ev et al.
TABLE 1 One-Pot Synthesis of Diselenophosphinic Se-Esters 7a–ha
Entry
Vinylselenide
Phosphine
Product
Isolate Yield
1
2
(1)
(2)
(3)
7a
7b
97
99
(3)
3
(1)
(4)
7c
98
4
5
6
(2)
(1)
(2)
(4)
7d
7e
7f
96
82
99
(5)
(5)
7
8
(1)
(2)
(6)
7g
7h
98
94
(6)
aThe reaction conditions: vinyl selenide (1.1 mmol), secondary phosphine (1.0 mmol), selenium (2.0 mmol), and 1,4-dioxane at 120–124°C for
20–40 min.
diselenophosphinic Se-esters, which are most in-
teresting for subsequent applications. From the
point of view of synthetic efficacy and atomic econ-
omy, direct addition of diselenophosphinic acids,
prospective pathway is particularly challenging be-
cause the free diselenophosphinic acids, in contrast
to dithiophosphinic acids [1], are very unstable and
instantly decompose [8]. More recently, we have de-
signed a convenient method for in situ generation
of diselenophosphinic acids (from secondary phos-
phines and elemental selenium), which immediately
≡
R2P(Se)SeH, to the C C or C C bonds of unsatu-
rated compounds would be the ideal route to func-
tional diselenophosphinic Se-esters. However, this
Heteroatom Chemistry DOI 10.1002/hc

Reaction of Vinyl Selenides with Secondary Phosphines and Elemental Selenium
3
add to electron-rich alkenes in a reaction mixture.
In this manner, novel functional Se-esters of dise-
lenophosphinic acids have been prepared by using
various alkenes, e.g., styrenes [9], vinyl ethers [10],
and vinyl sulfides [11].
Herein, we reported the synthesis of a new
family of diselenophosphinic Se-esters containing
alkylselanyl groups, R2P(Se)SeCH(Me)SeR´, based
on a selective atom-economic reaction between vinyl
selenides, secondary phosphines, and elemental
selenium.
bis(2-phenethyl)phosphine selenide (8) and elemen-
tal selenium in a 1.1:1:1 molar ratio under the same
conditions (120–124°C, 20–40 min, 1,4-dioxane) to
furnish Se-esters 7a,b in excellent yield (Scheme 1).
At the same time, divinyl selenide reacts with
secondary phosphines and elemental selenium un-
der similar conditions (120–124°C, 40 min, at 1:1:2
or 1:2:4 molar ratios) to furnish a mixture of eight
phosphorus-containing compounds, in which mono-
and diadducts of diselenophosphinic acids to divinyl
selenide prevail (1H, 31P NMR data).
The compounds 7a–h are stable in air and mois-
ture for several months. Their structures were estab-
RESULTS AND DISCUSSION
1
lished by H, 13C, 31P, and 77Se NMR as well as IR
We have found that the alkyl vinyl selenides 1, 2
interact easily with secondary phosphines 3–6 and
elemental selenium in a three-component type reac-
tion at 120–124°C (1,4-dioxane, 20–40 min) to afford
selectively hitherto unknown diselenophosphinic Se-
esters 7a–h in high to quantitative yields (Table 1).
The molar ratio of the reactants is close to stoichio-
metric (vinyl selenide/phosphine/Se = 1.1:1:2); how-
ever, the small excess (10 mol%) of vinyl selenide is
required to achieve the highest yields of products 7a–
h. Notably, the order of reactants mixing does not
affect the reaction course and the products’ yields.
As seen from Table 1, the reaction studied appears
to be of general character for secondary phosphines
bearing diverse organic groups.
At a lower temperature (80–100°C), the re-
action proceeds either too slow or does not
occur at all (at a temperature <80°C). For exam-
ple, vinyl selenide 1 reacts with secondary phos-
phine 3 and elemental selenium at 100°C for 1.5
h to afford Se-esters 7a in low yield (ꢀ20%) along
with bis(2-phenethyl)phosphine selenide (8); some
unreacted selenium being recovered. Noteworthy,
a similar three-component reaction involving alkyl
vinyl sulfides takes place under comparable con-
ditions (100°C, 1.5 h) to quantitatively give Se-
[ [1]-(alkylsulfanyl)ethyl]diselenophosphinates [11].
The same reaction with alkyl vinyl ethers is real-
ized even easily (90°C, 1–1.5 h), resulting in Se-
[1-(alkoxy)ethyl]diselenophosphinates in up to 99%
yield [10]. The observed order of the chalcogenides
reactivity in the addition studied (AlkOCH CH2 >
AlkSCH CH2 > AlkSeCH CH2) corresponds to the
expected drop of the stabilization effect in the inter-
mediate carbocation by the adjacent chalcogenide,
which once more supports the electrophilic nature
of the reaction.
spectroscopy. So, the 31P NMR spectra of 7a–h re-
veal sharp singlets at 49.05–51.85 ppm, flanked by
1
two pairs of 77Se satellites with JP-Se coupling con-
stants in the range of 359–368 and 740–750 Hz, indi-
cating the presence of P Se single bonds and P Se
double bonds in each compound. Accordingly, the
77Se NMR spectra of 7a–h display signals originat-
ing from the P Se and P Se bonds in the region of δ
= 352–354 and –248 to –245 ppm, respectively, with
matching 1JP-Se coupling constants. The alkylselenyl
moieties in the 77Se NMR spectra appear as low-field
singlets at 326–329 ppm. 1H and 13C NMR spectra of
compounds 7a–h display characteristic peaks corre-
sponding to the organic groups.
A plausible mechanism of the Se-esters 7a–h
formation is shown in Scheme 2. The first stage
is well-known [12] oxidation of secondary phos-
phine 3–6 with elemental selenium to give the sec-
ondary phosphine selenide A. At the second stage,
phosphine selenide A is further oxidized with sele-
nium to generate diselenophosphinic acid B, which
finally adds to the double bond of vinyl selenide
to afford ester 7. The last stage proceeds strictly
as the Markovnikov addition, since the alternative
products (anti-Markovnikov adducts) have not been
detected in the reaction mixtures (1H, 31P NMR).
Therefore, the reaction is the first example of elec-
trophilic addition of diselenophosphinic acids to
vinyl selenides.
The proposed mechanism is supported by the
following evidence: when vinyl selenides 1, 2 are
used in a deficient amount (i.e., at the molar ratio
1, 2/3–6 < 1), we observed that selenoanhydrides,
(R2P = Se)2Se, formed as by-products together with
Se-esters 7a–h. Obviously, the formation of the se-
lenoanhydrides is due to the decomposition of the
intermediate diselenophosphinic acids, R2P(Se)SeH
(Scheme 2). One of such selenoanhydrides, where
R = CH2CH2Ph (9), has been isolated from the re-
action mixture, and its structure was established by
X-ray (Fig. 1).
It has been found that the secondary phosphine
selenides may be alternatively used in the three-
component reaction instead of secondary phos-
phines. For instance, vinyl selenides 1, 2 react with
Heteroatom Chemistry DOI 10.1002/hc

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Artem’ev et al.
SCHEME 1 One-pot synthesis of diselenophosphinic Se-esters 7a,b.
SCHEME 2 A pathway of the three-component reaction.
merization of vinyl monomers as well as promising
sources of selenium for fabrication of metal selenide
nanocrystals. Also, availability of the three unequal
selenium atoms in esters 7a–h makes their potential
Se,Se’,Se"-donating ligands for the assembly of novel
selenium-rich metal complexes.
EXPERIMENTAL
General
All reactions were performed under inert atmo-
sphere (dry argon), using an enclosed glass tube or a
round-bottomed flask equipped with a condenser,
a thermometer, and an argon inlet. 1,4-Dioxane
was distilled from sodium/benzophenone under in-
ert atmosphere prior to use. Vinyl selenides 1, 2
were prepared according to the literature method
[13]. Secondary phosphines 3–6 were synthesized
by hydrophosphination of styrene, 4-chlorostyrene,
4-tert-butylstyrene, or 4-tert-butoxystyrene, respec-
tively [14]. Powdered gray selenium was used as
purchased. Phosphine selenide 8 was obtained by
oxidation of phosphine 3 with selenium [ [12]b]. The
elemental analyses were performed using a Flash EA
FIGURE 1 ORTEP diagram of the molecular structure of se-
lenoanhydride 9 (30% thermal ellipsoid probability). Selected
bond distances (Ǻ) and angles (o): P(1)–Se(1) 2.1025(10),
P(1)–Se(3) 2.2538(10), P(2)–Se(2) 2.0892(9), P(2)–Se(3)
2.2775(9), Se(1)–P(1)–Se(3) 103.35(4), Se(2)–P(2)–Se(3)
117.14(4), P(1)–Se(3)–P(2) 109.01(3).
1
1112 Series CHNS analyzer. The H, 13C, 31P, and
77Se NMR spectra were recorded using a Bruker AV-
400 spectrometer (400.13, 100.62, 161.98, and 76.31
MHz, respectively). 85% H3PO4/H2O was employed
as an external standard for 31P NMR, HMDS was
used for 1H and 13C NMR, and Me2Se was the exter-
nal standard for 77Se NMR.
CONCLUSIONS
In summary, examples of diselenophosphinic Se-
esters with alkylselanyl moieties have been synthe-
sized via the selective atom-economic reaction be-
tween vinyl selenides, secondary phosphines, and
elemental selenium. This reaction involves tandem
formation of unstable diselenophosphinic acids,
which immediately add to vinyl selenides to form
Markovnikov adducts, i.e., diselenophosphinic Se-
esters. The latter are prospective reversible addition
fragmentation chain transfer agents for living poly-
General Procedure for the Synthesis of
Diselenophosphinic Se-Esters 7a–h (Table 1)
Powdered gray selenium (1.0 mmol, 79 mg)
was added to a solution of vinyl selenide 1, 2
Heteroatom Chemistry DOI 10.1002/hc

Reaction of Vinyl Selenides with Secondary Phosphines and Elemental Selenium
5
(0.55 mmol) and secondary phosphine 3–6 (0.5
mmol) in 1,4-dioxane (4 mL) at ambient tempera-
ture. The suspension was stirred at 120–124°C until
the dissolution of selenium precipitate (20–40 min)
to give a yellowish transparent solution. The solvent
and excess of vinyl selenide were removed under re-
duced pressure (1 Torr, 50–60°C), and the residue
was purified by flash-chromatography (3 cm of sil-
ica gel, hexane-ether 1:1 as an eluent) to give dise-
lenophosphinic Se-ester 7a–h.
tallographic Data Centre via www.ccdc.cam.ac.uk/
data_request/cif.
REFERENCES
[1] (a) Hartley, F. R. The Chemistry of Organophospho-
rus Compounds, Vol. 4: Ter- and Quinque-Valent
Phosphorus Acids and Their Derivatives; Wiley: New
York, 1996; pp. 397–494; (b) Devillanova, F. A. Hand-
book of Chalcogen Chemistry: New Perspectives in
Sulfur, Selenium and Tellurium; RSC: Cambridge,
UK, 2007; pp. 286–343.
[2] For example, see, Hatfield, D. L.; Berry, M. J.; Glady-
shev, V. N. Selenium: Its Molecular Biology and Role
in Human Health; Springer: New York, 2012.
[3] (a) Moon, J.; Nam, H.; Kim, S.; Ryu, J.; Han, C.; Lee,
C.; Lee, S. Tetrahedron Lett 2008, 49, 5137–5140; (b)
Song, E.; Jo, Y.; Bae, G.; Oh, I.-K.; Jung, H. M.; Lee, S.
Bull Korean Chem Soc 2009, 30, 2129–2131; (c) Zeng,
J.; Zhu, J.; Zhang, Z.; Pan, X.; Zhang, W.; Cheng, Z.;
Zhu, X. J Polym Sci, Part A: Polym Chem 2012, 50,
2211–2218.
[4] Murai, T.; Maekawa, Y.; Monzaki, M.; Ando, T.;
Maruyama, T. Chem Commun 2013, 49, 9675–9677.
[5] Artem’ev, A. V.; Chernysheva, N. A.; Gusarova, N. K.;
Malysheva, S. F.; Yas’ko, S. V.; Albanov, A. I.; Trofi-
mov, B. A. Synthesis 2011, 1309–1313.
Synthesis of Esters 7a,b from Secondary
Phosphine Selenide 8 (Scheme 1)
Powdered gray selenium (0.5 mmol, 40 mg) was
added to a solution of vinyl selenide 1, 2 (0.55
mmol) and bis(2-phenethyl)phosphine selenide (8)
(0.5 mmol, 161 mg) in 1,4-dioxane (4 mL) at
ambient temperature. The suspension was stirred
at 120–124°C for 40 min to give a yellowish
transparent solution. The solvent and excess of
vinyl selenide were removed under reduced pres-
sure (1 Torr, 50–60°C), and the residue was pu-
rified by flash-chromatography (3 cm of silica
gel, hexane–ether 1:1 as the eluent) to give dise-
lenophosphinic Se-esters 7a,b in 95% and 86% yield,
respectively.
[6] Sarkar, B.; Fang, C.-S.; You, L.-Y.; Wang, J.-C.; Liu,
C. W. New J Chem 2009, 33, 626–633.
[7] (a) Hua, G.; Woollins, J. D. Polyhedron 2012, 42, 190–
195; (b) Hua, G.; Arachchige, K. S. A.; Slawin, A. M.
Z.; Woollins, J. D. Eur J Org Chem 2013, 7402–7410.
[8] Kuchen, W.; Knop, B. Chem Ber 1966, 99, 1663–1672.
[9] Gusarova, N. K.; Artem’ev, A. V.; Malysheva, S. F.;
Tarasova, O. A.; Trofimov, B. A. Tetrahedron Lett
2011, 52, 6985–6987.
[10] Gusarova, N. K.; Artem’ev, A. V.; Oparina, L. A.; Koly-
vanov, N. A.; Malysheva, S. F.; Vysotskaya, O. V.;
Trofimov, B. A. Synthesis 2012, 44, 431–438.
[11] Artem’ev, A. V.; Chernysheva, N. A.; Gusarova, N. K.;
Trofimov, B. A. J Sulfur Chem 2013, 34, 474–479.
[12] (a) Maier, L. Helv Chim Acta 1966, 49, 1000–1002; (b)
Sukhov, B. G.; Gusarova, N. K.; Ivanova, N. I.; Bog-
danova, M. V.; Kazheva, O. N.; Aleksandrov, G. G.;
D’yachenko, O. A.; Sinegovskaya, L. M.; Malysheva,S.
F.; Trofimov, B. A. J Struct Chem 2005, 46, 1066–
1071.
[13] (a) Gusarova, N. K.; Potapov, V. A.; Amosova, S. V.;
Trofimov, B. A. Zh Org Khim 1983, 19, 2477–2480;
Chem Abstr 1984, 101, 6574r; (b) Trofimov, B. A. Sul-
fur Rep 1992, 11, 207–231.
[14] Trofimov, B. A.; Brandsma, L.; Arbuzova, S. N.; Maly-
sheva, S. F.; Gusarova, N. K. Tetrahedron Lett 1994,
35, 7647–7650.
[15] SAINT V4.043: Software for the CCDC Detector Sys-
tem; Bruker Analytics X-ray System: Madison, WI,
1995.
[16] Sheldrick, G. M. SADABS, University of Gottingen:
Gottingen, Germany, 1996.
[17] Sheldrick, G. M. Acta Crystallogr, Sect A: Found Crys-
tallogr 2008, 64, 112.
[18] SHELXL 5.10 (PC version): Program Library for
Structure Solution and molecular Graphics; Bruker
Analytical X-ray System: Madison, WI, 1998.
X-Ray Crystallography of 9
A single crystal of 9 was mounted on glass fibers
with epoxy resin, and all geometric and intensity
data were collected using a Bruker APEXII CCD
diffractometer using graphite-monochromated Mo-
˚
Kα radiation (λ = 0.71073 A). Data reduction was
carried out with SAINT-Plus software [15]. An em-
pirical absorption correction was applied using the
SADABS program [16]. The structure was solved
by direct methods and refined by full-matrix least
squares on F2 using the SHELXTL software package
[17], incorporated in SHELXTL/PC version 5.10.28
[18].
Crystal data for 9: C32H36P2Se3, M = 719.43,
monoclinic, space group P21/c, a = 14.5059(8), b
= 10.1924(6), c = 23.5251(13), β = 107.6690(10),
V = 3314.1(3) Ǻ, Z = 4, ρcalcd. = 1.442 g/cm−3, μ
= 3.445, T = 296(2) K. Reflections collected/unique
= 42,388/6810 [R(int) = 0.0545], final R indi-
cates [I > 2σ(I)], R1 = 0.0381, wR2 = 0.0889.
CCDC 968547 contains the supplementary crystal-
lographic data for this paper. These data can be
obtained free of charge from The Cambridge Crys-
Heteroatom Chemistry DOI 10.1002/hc