A simple atom-economic synthesis of functional tertiary phosphine chalcogenides bearing furan or tetrahydrofuran rings

Article abstract of DOI:10.1055/s-0029-1216964

The first examples of hydrophosphorylation reactions of vinyl ethers of a series of furans are reported. Regiospecific addition of secondary phosphines, phosphine sulfides, or phosphine selenides to 2-[(vinyloxy)methyl]furan, 2-[1-(vinyloxy)butan-2yl]fura

Full text of DOI:10.1055/s-0029-1216964

PAPER
3427
A Simple Atom-Economic Synthesis of Functional Tertiary Phosphine
Chalcogenides Bearing Furan or Tetrahydrofuran Rings
F
uran-Substitute
u
d Tertiary P
d
hosphines an
m
d
Their Chalcogeni
i
des la A. Oparina, Svetlana F. Malysheva, Nina K. Gusarova, Nataliya A. Belogorlova, Oksana V. Vysotskaya,
Andrey V. Stepanov, Alexander I. Albanov, Boris A. Trofimov*
A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, 1 Favorsky Street, 664033 Irkutsk,
Russian Federation
Fax +7(3952) 4193461; E-mail: gusarova@irioch.irk.ru
Received 15 June 2009; revised 15 June 2009
We present a novel, efficient, and atom-economic method
Abstract: The first examples of hydrophosphorylation reactions of
for the preparation of functional tertiary phosphines and
phosphine chalcogenides containing furan and tetrahydro-
vinyl ethers of a series of furans are reported. Regiospecific addition
of secondary phosphines, phosphine sulfides, or phosphine se-
lenides to 2-[(vinyloxy)methyl]furan, 2-[1-(vinyloxy)butan-2-
furan rings in which readily available secondary phos-
yl]furan, or 2-[(vinyloxy)methyl]tetrahydrofuran proceeds under phines,11 phosphine chalcogenides,12 and vinyl furfuryl
UV irradiation to give the corresponding anti-Markovnikov adducts
in 72–99% yield.
ethers are used as starting materials. The initial phos-
phines are easily prepared from red phosphorus or phos-
Key words: ethers, phosphines, phosphorylation, radical reaction,
photochemistry
phine and styrenes or vinylpyridine (Scheme 1).
R
R
R
R
X
X
2
Pred (or PH3) +
X = O, S, Se
P
H
P
R
Hydrofuran and furan derivatives are widely distributed
as key structural units in a variety of natural products that
can be used as pharmaceuticals or fragrance compounds.1
The synthetic drugs that contain furan moieties include
antibiotics, cytostatics, tuberculostatics, and bacteri-
cides.2 Furan derivatives are also useful as versatile syn-
thetic building blocks for the preparation of heterocyclic
or acyclic organic compounds.3 In recent decades, there
has been a steady growth in interest in the use of organo-
phosphorus-substituted furans as potent ligands for the
design of metal-complex catalysts.4 For example, com-
plexes of (2-furyl)phosphines and (2-furyl)phosphine ox-
ides with palladium,5 rhodium,6 or gold7 have been used
successfully in various catalytic reactions and have shown
high efficiencies and high selectivities. Asymmetric ben-
zyl- and naphthyl(furyl)phosphines are recommended for
metal-mediated organic syntheses.4 Tertiary phosphine
oxides bearing furan and tetrahydrofuran rings are effec-
tive flame retardants for furan, epoxy, and unsaturated
polyester resins.8 Known syntheses of furyl phosphines
and phosphine chalcogenides involve the use of hazard-
ous phosphorus halides and alkali metals, and they require
multistep, laborious, and chemical- and solvent-consum-
ing procedures.9 Therefore, the search for more-straight-
forward and atom-economic (‘green’) routes to tertiary
phosphines and phosphine chalcogenides bearing furan
and tetrahydrofuran moieties is justifiable. The reactions
of phosphine adducts with alkenyl, alkynyl, or carbonyl-
substituted furans has attracted particular attention in this
respect.10
H
Scheme 1 Synthesis of phosphines and phosphine chalcogenides
The choice of vinyl furfuryl ethers is not arbitrary; these
ethers are produced by direct vinylation reactions of fur-
furyl alcohols with acetylene in a potassium hydroxide/
dimethyl sulfoxide system, a reaction that could be per-
formed on an industrial scale.13
Only a few publications deal with the radical addition re-
actions of secondary phosphines and phosphine chalco-
genides to vinyl ethers.14 It has been shown that
diorganophosphines and phosphine chalcogenides add to
alkyl vinyl ethers in the presence of 2,2¢-azobisisobuty-
ronitrile on heating to 60–70 °C14a–d or in the presence of
triethylborane and oxygen at room temperature14e to give
anti-Markovnikov adducts. However, the results of the re-
actions of vinyl furfuryl ethers with secondary phosphines
under radical initiation are far from predictable because of
the known retarding effect of furan derivatives on the
free-radical polymerization of vinyl compounds.15 Fur-
thermore, the furan ring can interact with radicals through
the C-5 carbon to form highly stable allylic-type radi-
cals.16
We found that vinyl ethers 1 and 2 reacted regiospecifical-
ly with the secondary phosphine 3 (entries 1 and 2), the
phosphine sulfides 4–6 (entries 3–5 and 8), or the phos-
phine selenides 7 (entries 6 and 9) and 8 (entry 7) under
mild conditions (UV irradiation, 30–35 °C, 1–28 h, 1,4-
dioxane) to give the corresponding anti-Markovnikov ad-
ducts 9a–i in high yields (up to 99%) (Table 1).
SYNTHESIS 2009, No. 20, pp 3427–3432
Advanced online publication: 21.08.2009
DOI: 10.1055/s-0029-1216964; Art ID: Z10309SS
© Georg Thieme Verlag Stuttgart · New York
x
x.
x
x
.
2
0
0
9
The formation of the tertiary phosphines 9a and 9b during
the reaction was confirmed by using 31P NMR spectrosco-
py (Table 1, entries 1, 2); however, during isolation and

3428
L. A. Oparina et al.
PAPER
Table 1 Reactions of Vinyl Furfuryl Ethers 1 and 2 with Secondary Phosphine 3 and Phosphine Chalcogenides 4–8
R2
R2
Y
Y
R1
R1
X
X
UV
P
+
P
1,4-dioxane
O
O
O
O
H
Y
9a–i
3–8
R2
1, 2
Y
R2
Entrya
Vinyl ether R1
Phosphine derivative
R2
H
Y
X
–
Time (h)
10
Adduct 9
Yield (%)b
1
2
3
4
5
6
7
8
9
1
2
1
1
1
1
1
2
2
H
Pr
H
H
H
H
H
Pr
Pr
3
3
4
5
6
7
8
4
7
CH
CH
CH
CH
N
ac
bc
c
82d
72d
99
98
96
97
98
99
98
H
–
28
H
S
1.5
t-Bu
H
S
1.5
d
e
S
20
H
CH
CH
CH
CH
Se
Se
S
1.0
f
t-Bu
H
1.0
g
h
i
5.5
H
Se
3.0
a All experiments were carried out by UV irradiation of 1 mmol of each reactant (quartz ampoule, 200-W Hg arc lamp) under argon in 1,4-
dioxane (0.5 mL).
b Isolated yield after purification.
c Detected in the reaction mixture by 31P NMR spectroscopy.
d Isolated and characterized as the corresponding phosphine oxides 10.
purification, the phosphines were easily oxidized by air In the course of isolation, phosphine 12a was easily oxi-
oxygen to form the corresponding tertiary phosphine ox- dized by oxygen in the air to give the corresponding phos-
ides 10a and 10b, respectively (Scheme 2).
phine oxide 13 (Scheme 3).
R1
O
O
O2
O2
P
P
12a
9a,b
O
O
O
O
10a,b
13
Scheme 2 Oxidation of tertiary phosphines
Scheme 3 Oxidation of bis(2-phenylethyl)[2-(tetrahydrofuran-2-yl-
methoxy)ethyl]phosphine
Note that bis(2-phenylethyl)phosphine oxide does not re-
act with vinyl ether 1 under these conditions (UV irradia-
tion, 30–35 °C, 20 h, 1,4-dioxane). This corresponds with
the known low reactivity of secondary phosphine oxides
in the presence of radical initiators,17 as a result of the high
P–H bond dissociation energy in the phosphine moiety.18
The results in Tables 1 and 2 show that the reactivity of
the phosphine derivatives in the reaction with vinyl furfu-
ryl ethers 1, 2, and 11 is in the following order: secondary
phosphine selenide > secondary phosphine sulfide >
secondary phosphine.
In conclusion, an efficient and atom-economic method for
the synthesis of new polyfunctional tertiary phosphine
chalcogenides containing furan moieties and alkoxy
groups has been developed on the basis of the radical ad-
dition of secondary phosphines or phosphine chalco-
genides. The new phosphine chalcogenide derivtives that
are formed are promising intermediates for the prepara-
tion of biologically active compounds, ligands for the de-
sign of metal complex catalysts, flame retardants, or
hybrid building blocks for organic synthesis.
2-[(Vinyloxy)methyl]tetrahydrofuran (11), an analogue
of ether 1 with a fully hydrogenated furan ring, also react-
ed readily and regiospecifically with secondary phosphine
3, phosphine sulfide 4, or the phosphine selenide 7 under
UV irradiation (30–35 °C, 1–5 h, 1,4-dioxane) to give the
corresponding anti-Markovnikov adducts 12a–c in near-
quantitative yields (Table 2). This supports the generality
of the method for the synthesis of new functional tertiary
phosphines and phosphine chalcogenides bearing furan
moieties.
Synthesis 2009, No. 20, 3427–3432 © Thieme Stuttgart · New York

PAPER
Furan-Substituted Tertiary Phosphines and Their Chalcogenides
3429
Table 2 Reaction of 2-[(Vinyloxy)methyl]tetrahydrofuran (11) with Bis(2-phenylethyl)phosphine (3), Bis(2-phenylethyl)phosphine Sulfide
(4), or Bis(2-phenylethyl)phosphine Selenide (7)
X
X
UV
P
P
+
H
1,4-Dioxane
O
O
O
O
3, 4, 7
11
12a–c
Entrya
Phosphine derivative
X
–
Time (h)
5.0
Product
12ac
Yield (%)b
1
2
3
3
4
7
96d
99
S
1.5
12b
Se
1.0
12c
98
a All experiments were carried out by UV irradiation of 1 mmol of each reactant (quartz ampoule, 200-W Hg arc lamp) under argon in
1,4-dioxane (0.5 mL).
b Isolated yield after purification.
c Detected in the reaction mixture by 31P NMR spectroscopy.
d Isolated and characterized as the corresponding phosphine oxide 13.
All manipulations were carried out under argon. 1,4-Dioxane was
distilled and dried as specified. 1H, 13C, and 31P NMR spectra were
recorded at 400.13, 100.62, and 161.98 MHz, respectively, in
CDCl3 solns with a Bruker DPX-400 spectrometer. Chemical shifts
are reported in d (ppm) relative to CDCl3 (1H, 13C) as internal stan-
dard or H3PO4 (31P) as external standard. IR spectra were recorded
on a Bruker IFS 25 spectrometer. Melting points were recorded on
a Stuart melting point apparatus, and are uncorrected.
[2-(2-Furylmethoxy)ethyl]bis(2-phenylethyl)phosphine Oxide
(10a)
Light-yellow oil; yield: 314 mg (82%).
IR (film): 3147, 3109, 3086, 3062, 3027, 3003, 2949, 2919, 2866,
1603, 1584, 1497, 1454, 1403, 1355, 1270, 1223, 1181, 1151, 1091,
1030, 1015, 990, 942, 920, 884, 837, 813, 751, 663, 600, 580 cm–1.
1H NMR: d = 2.03–2.07 (m, 6 H, CH2P), 2.84–2.88 (m, 4 H,
CH2Ph), 3.72–3.76 (m, 2 H, CH2O), 4.42 (s, 2 H, CH2-Fur), 6.27–
6.29 (m, 2 H, H3,4 in Fur), 7.14–7.30 (m, 10 H, Ph), 7.33 (m, 1 H,
H5 in Fur).
Tertiary Phosphines 9a,b, and 12a and Phosphine Oxides 10a,b,
and 13; General Procedure
13C NMR: d = 27.38 (d, 2JPC = 2.5 Hz, CH2Ph), 28.58 (d, 1JPC = 63.8
A soln of bis(2-phenylethyl)phosphine (1 mmol) and the vinyl ether
1, 2, or 11 (1 mmol) in 1,4-dioxane (0.5 mL) in a quartz ampoule
was irradiated by a 200-W Hg arc lamp for the time shown in
Table 1 or 2. During optimization, the reaction was monitored by
using 31P NMR spectroscopy to follow the disappearance of the sig-
nal of the starting phosphine (d = –69 ppm) and the appearance of a
new signal in the region d = –31 to –32 ppm, corresponding to the
tertiary phosphine. When the reaction was complete, Et2O (2 mL)
was added to the mixture and the soln was filtered. The solvents
were evaporated, and the phosphine 9a,b, or 12a was detected as the
major product in the crude mixture by 1H and 13C NMR spectrosco-
py. The crude product was dissolved in Et2O (2 mL) and passed
through a layer of alumina (activity level II, 0.5 cm), which was
then washed with additional Et2O (3 mL). Evaporation of the com-
bined solvent phases in vacuum (1–2 mm Hg, r.t.) gave the phos-
phine oxide 10a,b, or 13.
1
Hz, PCH2CH2O), 30.60 (d, JPC = 63.3 Hz, CH2P), 63.15 (d,
2JPC = 3.6 Hz, CH2O), 64.59 (CH2-Fur), 109.42 (C3 in Fur), 110.05
(C4 in Fur), 126.11 (p-C in Ph), 127.82 (o-C in Ph), 128.37 (m-C in
3
Ph), 140.80 (d, JPC = 12.8 Hz, ipso-C in Ph), 142.65 (C5 in Fur),
150.85 (C2 in Fur).
31P NMR: d = 47.12.
Anal. Calcd for C23H27O3P: C, 72.23; H, 7.12; P, 8.10. Found: C,
71.99; H, 7.18; P, 7.85.
{2-[1-(2-Furyl)butoxy]ethyl}bis(2-phenylethyl)phosphine (9b)
31P NMR: d = –31.52.
{2-[1-(2-Furyl)butoxy]ethyl}bis(2-phenylethyl)phosphine
Oxide (10b)
Light-yellow oil; yield: 306 mg (72%).
[2-(2-Furylmethoxy)ethyl]bis(2-phenylethyl)phosphine (9a)
1H NMR: d = 1.73–1.81 (m, 6 H, CH2P), 2.69–2.80 (m, 4 H,
CH2Ph), 3.60–3.68 (m, 2 H, CH2O), 4.32 (s, 2 H, CH2-Fur), 6.30 (d,
3J = 3.0 Hz, 1 H, H3 in Fur), 6.31 (dd, 3J = 3.0 Hz, 3J = 1.8 Hz, 1 H,
H4 in Fur), 7.14–7.26 (m, 10 H, Ph), 7.37 (m, 1 H, H5 in Fur).
IR (film): 3108, 3086, 3062, 3028, 3002, 2958, 2932, 2871, 1603,
1584, 1497, 1455, 1403, 1381, 1331, 1221, 1155, 1128, 1108, 1090,
1071, 1030, 1004, 984, 920, 884, 846, 810, 751, 700, 664, 599, 581
cm–1.
3
1H NMR: d = 0.86 (t, J = 7.4 Hz, 3 H, Me), 1.18–1.24 (m, 2 H,
2
2
13C NMR: d = 22.23 and 27.49 (d, JPC = 11.1 Hz and JPC = 11.9
CH2Me), 1.78–1.90 (m, 2 H, CH2Et), 1.95–2.12 (m, 6 H, CH2P),
2.84–2.94 (m, 4 H, CH2Ph), 3.57–3.59 (m, 2 H, CH2O), 4.23 (t,
3J = 7.2 Hz, 1 H, CH-Fur), 6.22 (d, 3J = 3.1 Hz, 1 H, H3 in Fur), 6.28
(dd, 3J = 1.8 Hz, 3J = 3.1 Hz, 1 H, H4 in Fur), 7.12–7.28 (m, 10 H,
Ph), 7.29 (m, 1 H, H5 in Fur).
Hz, CH2Ph), 29.42 and 32.20 (d, 1JPC = 15.1 Hz and 1JPC = 15.9 Hz,
1
CH2P), 34.51 (d, JPC = 10.3 Hz, PCH2CH2O), 64.65 (CH2-Fur),
67.88 (d, 2JPC = 21.4 Hz, CH2O), 109.10 (C3 in Fur), 110.19 (C4 in
Fur), 125.90 (p-C in Ph), 128.08 (o-C in Ph), 128.38 (m-C in Ph),
142.65 (C5 in Fur), 142.79 (d, 3JPC = 11.1 Hz, ipso-C in Ph), 151.89
(C2 in Fur).
13C NMR: d = 13.90 (Me), 19.02 (CH2Me), 27.68 and 27.76 (d,
1
2JPC = 3.2 Hz, CH2Ph), 28.98 (d, JPC = 63.5 Hz, PCH2CH2O),
31P NMR: d = –31.89.
30.48 and 31.35 (d, 1JPC = 62.7 Hz and 1JPC = 63.5 Hz, CH2P), 36.14
2
(CH2Et), 62.11 (d, JPC = 4.0 Hz, CH2O), 75.32 (CH-Fur), 108.40
(C3 in Fur), 110.11 (C4 in Fur), 126.47 (p-C in Ph), 128.20 (o-C in
Synthesis 2009, No. 20, 3427–3432 © Thieme Stuttgart · New York

3430
L. A. Oparina et al.
PAPER
Ph), 128.73 (m-C in Ph), 141.30 (d, 3JPC = 13.9 Hz, ipso-C in Ph),
IR (KBr): 3147, 3119, 3083, 3059, 3026, 2997, 2944, 2928, 2898,
2866, 1600, 1582, 1497, 1486, 1453, 1410, 1397, 1352, 1267, 1225,
1212, 1178, 1148, 1128, 1093, 1028, 1014, 1004, 990, 975, 946,
931, 917, 883, 835, 802, 758, 748, 702, 673, 592, 573, 544 cm–1.
1H NMR: d = 2.11–2.20 (m, 6 H, CH2P), 2.88–2.92 (m, 4 H,
CH2Ph), 3.78–3.86 (m, 2 H, CH2O), 4.43 (s, 2 H, CH2-Fur), 6.29 (m,
2 H, H3,4 in Fur), 7.13–7.27 (m, 10 H, Ph), 7.32 (br s, 1 H, H5 in Fur).
142.38 (C5 in Fur), 154.06 (C2 in Fur).
31P NMR: d = 47.41.
Anal. Calcd for C26H33O3P: C, 73.56; H, 7.84; P, 7.30. Found: C,
73.54; H, 7.70; P, 7.28.
Bis(2-phenylethyl)[2-(tetrahydrofuran-2-ylmethoxy)eth-
yl]phosphine (12a)
1
13C NMR: d = 28.53 (CH2Ph), 31.78 (d, JPC = 49.5 Hz,
1H NMR: d = 1.52–1.59 (m, 1 H, H3 in THF), 1.83–1.86 (m, 6 H, H4
in THF, CH2P), 1.86–1.90 (m, 1 H, H3 in THF), 2.06–2.11 (m, 2 H,
CH2P), 2.69–2.75 and 2.84–2.92 (m, 4 H, CH2Ph), 3.38–3.44 (m, 2
H, CH2-THF), 3.59–3.64 (m, 2 H, H5 in THF), 3.67–3.80 (m, 2 H,
CH2O), 3.97–4.01 (m, 1 H, H2 in THF), 7.15–7.28 (m, 10 H, Ph).
PCH2CH2O), 33.53 (d, 1JPC = 48.3 Hz, CH2P), 64.06 (d, 2JPC = 4.0
Hz, CH2O), 64.92 (CH2-Fur), 109.61 (C4 in Fur), 110.27 (C3 in Fur),
126.36 (p-C in Ph), 128.22 (o-C in Ph), 128.58 (m-C in Ph), 140.80
(d, 3JPC = 14.0 Hz, ipso-C in Ph), 142.86 (C5 in Fur), 151.13 (C2 in
Fur).
13C NMR: d = 25.39 (C4 in THF), 27.26 (C3 in THF), 27.35 (d,
31P NMR: d = 48.19.
2
1JPC = 9.2 Hz, CH2P), 27.47 (d, JPC = 5.8 Hz, CH2Ph), 29.10 (d,
Anal. Calcd for C23H27O2PS: C, 69.32; H, 6.83; P, 7.77; S, 8.05.
Found: 69.40; H, 6.72; P, 7.29; S, 8.08.
2
1JPC = 13.0 Hz, PCH2CH2O), 32.00 (d, JPC = 14.6 Hz, CH2Ph),
2
68.03 (d, JPC = 6.5 Hz, CH2O), 69.15 (C5 in THF), 73.39 (CH2-
THF), 77.45 (C2 in THF), 125.73 (p-C in Ph), 127.89 (o-C in Ph),
Bis[2-(4-tert-butylphenyl)ethyl][2-(2-furylmethoxy)ethyl]phos-
phine Sulfide (9d)
Colorless oil; yield: 469 mg (92%).
128.21 (m-C in Ph), 140.89 (d, 3JPC = 13.7 Hz, ipso-C in Ph).
31P NMR: d = –31.42.
IR (film): 3117, 3092, 3054, 3024, 3008, 2962, 2906, 2867, 1516,
1475, 1463, 1446, 1394, 1364, 1269, 1220, 1203, 1150, 1108, 1093,
1051, 993, 920, 884, 854, 817, 775, 739, 599, 565 cm–1.
Bis(2-phenylethyl)[2-(tetrahydrofuran-2-ylmethoxy)eth-
yl]phosphine Oxide (13)
Light-yellow oil; yield: 371 mg (96%).
1H NMR: d = 1.29 (s, 18 H, Me), 2.12–2.23 (m, 6 H, CH2P), 2.84–
IR (film): 3108, 3086, 3062, 3027, 3002, 2948, 2921, 2867, 1603,
1584, 1497, 1455, 1403, 1373, 1365, 1271, 1222, 1155, 1117, 1083,
1030, 947, 838, 775, 752, 699, 580 cm–1.
3
2.96 (m, 4 H, CH2C6H4), 3.84 (dt, 3JHH = 6.0, JPH = 18.1 Hz, 2 H,
CH2O), 4.46 (s, 2 H, CH2-Fur), 6.30–6.33 (m, 2 H, H3,4 in Fur),
7.07–7.35 (m, 8 H, C6H4), 7.41 (br s, 1 H, H5 in Fur).
1H NMR: d = 1.54–1.55 (m, 1 H, H3 in THF), 1.77–1.84 (m, 2 H, H4
in THF), 1.86–1.90 (m, 1 H, H3 in THF), 2.04–2.15 (m, 6 H, CH2P),
2.90 (m, 4 H, CH2Ph), 3.41 (dd, 2J = 10.2 Hz, 3J = 6.7 Hz, 1 H, CH2-
13C NMR: d = 27.95 (d, 2JPC = 2.9, CH2C6H4), 31.31 (Me), 31.55 (d,
1
1JPC = 42.9 Hz, PCH2CH2O), 33.42 (d, JPC = 48.1 Hz, PCH2),
2
34.34 (CCH3), 64.05 (d, JPC = 4.0 Hz, CH2O), 64.90 (CH2-Fur),
2
3
THF), 3.47 (dd, J = 10.2 Hz, J = 3.5 Hz, 1 H, CH2-THF), 3.70–
3.80 (m, 2 H, H5 in THF), 3.78–3.79 (m, 2 H, CH2O), 3.97–3.99 (m,
1 H, H2 in THF), 7.12–7.29 (m, 10 H, Ph).
109.65 (C4 in Fur), 110.25 (C3 in Fur), 125.40 (C2,6 in C6H4), 127.88
(C3,5 in C6H4), 137.64 (C1 in C6H4), 142.83 (C4 in C6H4), 149.24 (C5
in Fur), 151.06 (C2 in Fur).
13C NMR: d = 25.57 (C4 in THF), 27.64 (CH2Ph), 27.99 (C3 in
31P NMR: d = 47.97.
1
THF), 28.81 (d, JPC = 64.0 Hz, PCH2CH2O), 30.73 and 30.79 (d,
1JPC = 63.3 Hz and 1JPC = 62.9 Hz, CH2P), 64.67 (d, 2JPC = 3.5 Hz,
CH2O), 68.26 (C5 in THF), 73.82 (CH2-THF), 77.72 (C2 in THF),
126.43 (p-C in Ph), 128.11 (o-C in Ph), 128.66 (m-C in Ph), 141.02
(d, 3JPC = 13.4 Hz, ipso-C in Ph).
Anal. Calcd for C31H43O2PS: C, 72.90; H, 8.49; P, 6.06; S, 6.28.
Found: C, 72.58; H, 8.30; P, 6.02; S, 6.31.
2-(2-Furylmethoxy)ethyl{bis[2-(2-pyridinyl)ethyl]}phosphine
Sulfide (9e)
Light-yellow oil; yield: 365 mg (91%).
31P NMR: d = 42.78.
Anal. Calcd for C23H31O3P: C, 71.48; H, 8.09; P, 8.01. Found: C,
71.23; H, 8.10; P, 8.09.
IR (film): 3158, 3113, 3070, 3064, 3008, 2946, 2920, 2863, 1592,
1569, 1503, 1474, 1436, 1405, 1354, 1225, 1150, 1123, 1092, 1051,
1015, 994, 946, 920, 884, 765, 629, 601, 567, 542 cm–1.
1H NMR: d = 2.0–2.09 (m, 2 H, PCH2CH2O), 2.23–2.35 (m, 4 H,
CH2P), 3.0–3.06 (m, 4 H, CH2Py), 3.80 (dt, 3JHH = 6.3, 3JHP = 17.5
Hz, 2 H, CH2O), 4.38 (s, 2 H, CH2-Fur), 6.24 (d, 3J = 2.8 Hz, 1 H,
H3 in Fur), 6.27 (dd, 3J = 2.8, 3J = 1.9 Hz, 1 H, H4 in Fur), 7.04 (dd,
3J = 4.4, 3J = 7.0 Hz, 2 H, H5 in Py), 7.09 (d, 3J = 7.8 Hz, 2 H, H5 in
Py), 7.26 (m, 1 H, H5 in Fur), 7.52 (ddd, 3J = 7.5, 3J = 7.0, 4J = 1.9
Hz, 2 H, H4 in Py), 8.42 (m, 2 H, H6 in Py).
Tertiary Phosphine Sulfides 9c–e,h, and 12b, and the Phosphine
Selenides 9f,g,i, and 12c: General Procedure
A soln of a phosphine chalcogenide 4–8 (1 mmol) and vinyl ether 1,
2, or 11 (1 mmol) in 1,4-dioxane (0.5 mL) in a quartz ampoule was
irradiated by a 200-W Hg arc lamp for the time shown in Table 1 or
2. The reaction was monitored by using 31P NMR spectroscopy to
follow the disappearance of the signal of the starting phosphine
chalcogenides (d = 20–23 ppm for sulfides 4–6 and 2–3 ppm for se-
lenides 7 and 8), and the appearance of a new signal in the region
d = 47–49 for tertiary phosphine sulfides 9c–e,h, and 12b, and at
35–37 ppm for the phosphine selenides 9f,g,i, and 12c. The mixture
was added to Et2O (3 mL) and the soln was filtered and passed
through a layer of alumina (activity level II, 0.5 cm), which was
then washed with 1:1 hexane–Et2O (3 mL). The combined solvent
phases were distilled off under reduced pressure to give the phos-
phine chalcogenides 9c–i, 12b, and 12c.
1
13C NMR: d = 30.67 (CH2Py), 31.07 (d, JPC = 50.2 Hz,
PCH2CH2O), 31.71 (d, 1JPC = 50.2 Hz, CH2P), 64.06 (d, 2JPC = 2.7
Hz, CH2O), 64.86 (CH2-Fur), 109.61 (C3 in Fur), 110.18 (C4 in Fur),
121.47 (C5 in Py), 122.99 (C3 in Py), 136.55 (C4 in Py), 142.71 (C5
in Fur), 149.13 (C6 in Py), 151.21 (C2 in Fur), 160.04 (d, 3JPC = 15.0
Hz, C2 in Py).
31P NMR: d = 48.93.
Anal Calcd for C21H25N2O2PS: C, 62.98; H, 6.29; N, 7.0; P, 7.73; S,
8.01. Found: C, 62.62; H, 6.22; N, 7.25; P, 7.63; S, 7.95.
[2-(2-Furylmethoxy)ethyl]bis(2-phenylethyl)phosphine Sulfide
(9c)
Colorless crystalline solid; yield: 395 mg (99%); mp 89 °C (hex-
ane).
Synthesis 2009, No. 20, 3427–3432 © Thieme Stuttgart · New York

PAPER
Furan-Substituted Tertiary Phosphines and Their Chalcogenides
3431
2-(2-Furylmethoxy)ethyl]bis(2-phenylethyl)phosphine Selenide
(9f)
Colorless solid; yield: 388 mg (87%); mp 84 °C (hexane).
31P NMR: d = 48.65.
Anal. Calcd for C26H33O2PS: C, 70.88; H, 7.55; P, 7.03; S, 7.28.
Found: C, 70.44; H, 7.57; P, 7.02; S, 7.50.
IR (KBr): 3147, 3118, 3082, 3059, 3024, 2997, 2943, 2928, 2897,
2866, 1600, 1582, 1496, 1487, 1467, 1453, 1392, 1352, 1336, 1266,
1224, 1212, 1178, 1147, 1093, 1028, 1014, 1003, 990, 930, 917,
883, 852, 833, 820, 800, 772, 742, 703, 600, 570, 498, 459 cm–1.
{2-[1-(2-Furyl)butoxy]ethyl}bis(2-phenylethyl)phosphine
Selenide (9i)
Colorless oil; yield: 473 mg (97%).
1H NMR: d = 2.22–2.31 (m, 6 H, CH2P), 2.88–2.93 (m, 4 H,
IR (film): 3144, 3107, 3086, 3062, 3026, 3001, 2957, 2932, 2870,
1603, 1584, 1497, 1463, 1454, 1400, 1382, 1332, 1270, 1219, 1179,
1151, 1093, 1074, 1030, 1010, 980, 948, 920, 884, 811, 747, 699,
664, 599, 575, 495, 462 cm–1.
CH2Ph), 3.83 (dt, 3JHH = 5.9, 3JPH = 19.7 Hz, 2 H, CH2O), 4.45 (s, 2
4
H, CH2-Fur), 6.29 (dd, 3J = 3.2, J = 0.9 Hz, 1 H, H3 in Fur), 6.31
3
(dd, J = 3.2, 3J = 1.8 Hz, 1 H, H4 in Fur), 7.14–7.27 (m, 10 H, Ph),
7.28 (dd, 3J = 1.8, 4J = 0.9 Hz, 1 H, H5 in Fur).
1H NMR: d = 0.85 (t, 3J = 7.4 Hz, 3 H, Me), 1.27 (m, 2 H, CH2Me),
1
13C NMR: d = 29.41 (CH2Ph), 31.51 (d, JPC = 42.8 Hz,
1.77 (m, 2 H, CH2Et), 2.15–2.30 (m, 6 H, CH2P), 2.86–2.95 (m, 4
PCH2CH2O), 33.17 (d, 1JPC = 41.3 Hz, PCH2), 64.80 (CH2O), 65.05
(CH2-Fur), 109.79 (C3 in Fur), 110.38 (C4 in Fur), 126.52 (p-C in
Ph), 128.37 (o-C in Ph), 128.81 (m-C in Ph), 140.66 (d, ipso-C in
Ph, 3JPC = 14.7 Hz), 143.01 (C5 in Fur), 151.17 (C2 in Fur).
H, CH2Ph), 3.60–3.69 (m, 2 H, CH2O), 4.25 (t, J = 7.0 Hz, 1 H,
3
3
3
CH-Fur), 6.23 (d, J = 3.1 Hz, 1 H, H3 in Fur), 6.28 (dd, J = 3.1,
3J = 1.6 Hz, 1 H, H4 in Fur), 7.12–7.28 (m, 10 H, Ph), 7.34 (m, 1 H,
H5 in Fur).
31P NMR: d = 35.93.
13C NMR: d = 13.70 (Me), 18.80 (CH2Me), 29.19 and 29.14 (d,
2
1
2JPC = 2.3 and JPC = 2.7 Hz, CH2Ph), 32.69 (d, JPC = 41.4 Hz,
Anal. Calcd for C23H27O2PSe: C, 62.02; H, 6.11; P, 6.95; Se, 17.73.
Found: C, 62.26; H, 6.14; P, 6.81; Se, 17.95.
PCH2CH2O), 31.48 (d, 1JPC = 42.6 Hz, PCH2), 35.90 (CH2Et), 62.12
2
(d, JPC = 4.2 Hz, CH2O), 75.19 (CH-Fur), 108.30 (C3 in Fur),
109.92 (C4 in Fur), 126.33 (p-C in Ph), 128.20 (o-C in Ph), 128.51
(m-C in Ph), 140.53 (d, 3JPC = 15.3 Hz, ipso-C in Ph), 142.18 (C5 in
Fur), 153.76 (C2 in Fur).
Bis[2-(4-tert-butylphenyl)ethyl][2-(2-furylmethoxy)ethyl]phos-
phine Selenide (9g)
Colorless oil; yield: 507 mg (91%).
31P NMR: d = 35.97.
IR (film): 3117, 3092, 3055, 3024, 2962, 2906, 2867, 1517, 1509,
1475, 1464, 1443, 1413, 1394, 1364, 1219, 1150, 1107, 1093, 1016,
966, 943, 921, 884, 871, 853, 839, 816, 740, 600, 564, 473 cm–1.
Anal. Calcd for C26H33O2PSe: C, 64.06; H, 6.82; P, 6.35; Se, 16.20.
Found: C, 64.04; H, 7.04; P, 6.61; Se, 15.82.
1H NMR: d = 1.29 (s, 18 H, Me), 2.23–2.31 (m, 6 H, CH2P), 2.85–
2.93 (m, 4 H, CH2C6H4), 3.85 (dt,, 3JHH = 6.0, 3JPH = 18.9 Hz, 2 H,
CH2O), 4.47 (s, 2 H, CH2-Fur), 6.31 (dd, 3J = 3.4, 4J = 0.7 Hz, 1 H,
H3 in Fur), 6.33 (dd, 3J = 3.4, 3J = 1.6 Hz, 1 H, H4 in Fur), 7.09–7.30
(m, 8 H, C6H4), 7.36 (dd, 3J = 1.6, 4J = 0.7 Hz, 1 H, H5 in Fur).
Bis(2-phenylethyl)[2-(tetrahydrofuran-2-ylmethoxy)eth-
yl]phosphine Sulfide (12b)
Crystals; yield: 398 mg (99%); mp 58–59 °C (hexane).
IR (KBr): 3103, 3084, 3061, 3027, 3001, 2960, 2925, 2860, 1602,
1583, 1496, 1453, 1399, 1373, 1359, 1331, 1227, 1211, 1189, 1179,
1111, 1086, 1028, 1007, 946, 928, 919, 832, 796, 771, 754, 698,
2
13C NMR: d = 28.73 (d, JPC = 2.6 Hz, CH2C6H4), 31.20 (d,
1
1JPC = 43.3 Hz, PCH2CH2O), 31.32 (Me), 33.0 (d, JPC = 41.1 Hz,
677, 594, 546, 496 cm–1
PCH2), 34.37 (CCH3), 64.72 (d, 2JPC = 3.7 Hz, CH2O), 64.93 (CH2-
Fur), 109.71 (C4 in Fur), 110.27 (C3 in Fur), 125.48 (C2,6 in C6H4),
127.93 (C3,5 in C6H4), 137.41 (d, 3JPC = 14.7 Hz, C1 in C6H4), 142.91
(C4 in C6H4), 149.31 (C5 in Fur), 151.03 (C2 in Fur).
.
1H NMR: d = 1.51 (m, 1 H, H3 in THF), 1.80 (m, 2 H, H4 in THF),
1.87 (m, 1 H, H3 in THF), 2.19 (m, 6 H, CH2P), 2.93 (dt, 3JHH = 8.1,
3JPH = 8.84 Hz, 4 H, CH2Ph), 3.41 (dd, 2J = 10.3, 3J = 3.9 Hz, 1 H,
2
3
CH2-THF), 3.46 (dd, J = 10.3, J = 6.6 Hz, 1 H, CH2-THF), 3.86
(m, 2 H, CH2O), 3.70 and 3.78 (m, 2 H, H5 in THF), 3.98 (m, 1 H,
H2 in THF), 7.18 (m, 6 H, o-C, p-C in Ph), 7.27 (m, 4 H, m-C in Ph).
31P NMR: d = 36.26.
Anal. Calcd for C31H43O2PSe: C, 66.77; H, 7.77; P, 5.55; Se, 14.16.
Found: C, 66.83; H, 7.73; P, 5.48; Se, 14.10.
13C NMR: d = 25.46 (C4 in THF), 27.90 (C3 in THF), 28.49 (d,
1
2JPC = 2.9 Hz, CH2Ph), 31.48 (d, JPC = 50.3 Hz, PCH2CH2O),
{2-[1-(2-Furyl)butoxy]ethyl}bis(2-phenylethyl)phosphine
Sulfide (9h)
Colorless oil; yield: 431 mg (98%).
1
1
33.46 and 33.33 (d, JPC = 48.1 and JPC = 48.4 Hz, CH2P), 65.21
(d, JPC = 3.7 Hz, CH2O), 68.13 (C5 in THF), 73.78 (CH2-THF),
2
77.52 (C2 in THF), 126.31 and 126.32 (p-C in Ph), 128.14 and
128.52 (o-C, m-C in Ph), 140.68 (d, 3JPC = 14.7 Hz, ipso-C in Ph).
IR (film): 3108, 3086, 3062, 3027, 3002, 2958, 2932, 2870, 1603,
1584, 1497, 1454, 1400, 1384, 1332, 1269, 1219, 1179, 1150, 1091,
1030, 1009, 983, 947, 920, 884, 860, 842, 810, 749, 698, 677, 600,
557, 545, 495 cm–1.
31P NMR: d = 47.57.
Anal. Calcd for C23H31O2PS: C, 68.63; H, 7.76; P, 7.69; S, 7.97.
Found: C, 69.09; H, 7.94; P, 8.03; S, 8.57.
3
1H NMR: d = 0.85 (t, J = 7.3 Hz, 3 H, Me), 1.23–1.31 (m, 2 H,
CH2Me), 1.72–1.85 (m, 2 H, CH2Et), 2.04–2.35 (m, 6 H, CH2P),
2.86–2.93 (m, 4 H, CH2Ph), 3.60–3.69 (m, 2 H, CH2O), 4.25 (t,
3J = 7.3 Hz, 1 H, CH-Fur), 6.23 (d, 3J = 2.7 Hz, 1 H, H3 in Fur), 6.28
(m, 1 H, H4 in Fur), 7.12–7.28 (m, 10 H, Ph), 7.30 (m, 1 H, H5 in
Fur).
Diphenylethyl[2-(tetrahydrofuran-2-ylmethoxy)ethyl]phos-
phine Selenide (12c)
Colorless oil; yield: 440 mg (98%).
IR (film): 3105, 3084, 3060, 3026, 2998, 2973, 2947, 2923, 2896,
2866, 1602, 1583, 1496, 1473, 1453, 1402, 1360, 1335, 1285, 1226,
1211, 1180, 1135, 1123, 1084, 1007, 973, 947, 926, 929, 835, 795,
13C NMR: d = 13.73 (Me), 18.82 (CH2Me), 28.37 (d, 2JPC = 2.9 Hz,
CH2Ph), 31.72 (d, 1JPC = 49.5 Hz, PCH2CH2O), 32.67 and 33.66 (d,
768, 750, 699, 659, 572, 499, 459 cm–1
2
1JPC = 48.1 Hz, PCH2), 35.92 (CH2Et), 62.49 (d, JPC = 4.4 Hz,
.
CH2O), 75.16 (CH-Fur), 108.30 (C3 in Fur), 109.92 (C4 in Fur),
126.29 and 126.31 (p-C in Ph), 128.17 and 128.18 (o-C in Ph),
128.51 and 128.52 (m-C in Ph), 140.78 (d, 3JPC = 15.4 Hz, ipso-C in
Ph), 142.20 (C5 in Fur), 153.72 (C2 in Fur).
1H NMR: d = 1.50 (m, 1 H, H3 in THF), 1.80 (m, 2 H, H4 in THF),
1.87 (m, 1 H, H3 in THF), 2.28 (m, 6 H, CH2P), 2.92 (m, 4 H,
CH2Ph), 3.41 (dd, 2J = 10.3, 3J = 6.6 Hz, 1 H, CH2-THF), 3.48 (dd,
2J = 10.3, 3J = 3.9 Hz, 1 H, CH2-THF), 3.74 and 3.83 (m, 2 H, H5 in
Synthesis 2009, No. 20, 3427–3432 © Thieme Stuttgart · New York

3432
L. A. Oparina et al.
PAPER
THF), 3.88 (m, 2 H, CH2O), 3.98–4.01 (m, 1 H, H2 in THF), 7.18–
7.28 (m, 10 H, Ph).
(8) (a) Varbanov, S.; Borisov, G. Eur. Polym. J. 1984, 20, 185.
(b) Varbanov, S.; Borisov, G. Acta Polym. 2003, 39, 507.
(9) (a) Tolmachev, A. A.; Ivonin, S. P.; Kharchenko, A. V.;
Kozlov, E. S. J. Gen. Chem. USSR (Engl. Transl.) 1991, 61,
778. (b) Santelli-Rouvier, C.; Coin, C.; Toupet, L.; Santelli,
V. J. Organomet. Chem. 1995, 495, 91. (c) Zapata, A. J.;
Rondon, A. C. Org. Prep. Proced. Int. 1995, 27, 567.
(d) Appel, M.; Blaurock, S.; Berger, S. Eur. J. Org. Chem.
2002, 7, 1143.
(10) (a) Trofimov, B. A.; Gusarova, N. K.; Arbuzova, S. N. Russ.
Chem. Rev. 1999, 68, 240. (b) Ivanova, N. I.; Gusarova, N.
K.; Nikitina, E. A.; Medvedeva, S. A.; Alpert, M. L.;
Trofimov, B. A. Chem. Heterocycl. Comp. (Engl. Transl.)
2004, 40, 426.
13C NMR: d = 25.66 (C4 in THF), 28.10 (C3 in THF), 28.44 and
2
1
28.48 (d, JPC = 2.9 Hz, CH2Ph), 31.28 (d, JPC = 43.3 Hz,
1
1
PCH2CH2O), 33.27 and 33.06 (d, JPC = 41.1 and JPC = 41.5 Hz,
CH2P), 66.11 (d, JPC = 3.7 Hz, CH2O), 68.35 (C5 in THF), 74.01
2
(CH2-THF), 77.70 (C2 in THF), 126.57 (p-C in Ph), 128.39 and
128.74 (o-C, m-C in Ph), 140.65 (d, 3JPC = 14.7 Hz, ipso-C in Ph).
31P NMR: d = 36.71.
Anal. Calcd for C21H31O2PSe: C, 61.47; H, 6.95; P, 6.89; Se, 17.57.
Found: C, 61.83; H, 6.80; P, 6.89; Se, 17.62.
Acknowledgment
(11) (a) Arbuzova, S. N.; Brandsma, L.; Gusarova, N. K.;
Trofimov, B. A. Recl. Trav. Chim. Pays-Bas 1994, 113,
575. (b) Trofimov, B. A.; Brandsma, L.; Arbuzova, S. N.;
Malysheva, S. F.; Gusarova, N. K. Tetrahedron Lett. 1994,
35, 7647.
(12) Gusarova, N. K.; Bogdanova, M. V.; Ivanova, N. I.;
Chernysheva, N. A.; Sukhov, B. G.; Sinegovskaya, L. M.;
Kazheva, O. N.; Alexandrov, G. G.; D’yachenko, O. A.;
Trofimov, B. A. Synthesis 2005, 3103.
This work has been carried out with financial support of leading sci-
entific schools by the President of the Russian Foundation (grant
NSH-263.2008.3) and the Russian Foundation of Basic Research
(grant no. 07-03-00562).
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