Convenient one-pot synthesis of vinyl ethers from phenyl 2-hydroxyalkyl selenides

Article abstract of DOI:10.1080/00397910500296901

Vinyl ethers were prepared with good yields in a one-pot, two-step transformation by O-alkylation reaction of phenyl 2-hydroxyalkyl selenides with primary or secondary organic halides followed by oxidation elimination with 30% hydrogen peroxide. Copyright

Full text of DOI:10.1080/00397910500296901

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Convenient One‐Pot Synthesis
of Vinyl Ethers from Phenyl
2‐Hydroxyalkyl Selenides
Shou‐Ri Sheng a , Hai‐Rong Luo a , Wu‐Kang Sun a ,
Xiao‐Ling Liu a , Qin Xin a & Qiu‐Ying Wang a
a College of Chemistry and Chemical Engineering,
Jiangxi Normal University, Nanchang, China
Published online: 22 Aug 2006.
To cite this article: Shou‐Ri Sheng , Hai‐Rong Luo , Wu‐Kang Sun , Xiao‐Ling Liu , Qin
Xin & Qiu‐Ying Wang (2005) Convenient One‐Pot Synthesis of Vinyl Ethers from Phenyl
2‐Hydroxyalkyl Selenides, Synthetic Communications: An International Journal for
Rapid Communication of Synthetic Organic Chemistry, 35:22, 2839-2845
To link to this article: http://dx.doi.org/10.1080/00397910500296901
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Synthetic Communicationsw, 35: 2839–2845, 2005
Copyright # Taylor & Francis, Inc.
ISSN 0039-7911 print/1532-2432 online
DOI: 10.1080/00397910500296901
Convenient One-Pot Synthesis of Vinyl
Ethers from Phenyl 2-Hydroxyalkyl
Selenides
Shou-Ri Sheng, Hai-Rong Luo, Wu-Kang Sun, Xiao-Ling Liu,
Qin Xin, and Qiu-Ying Wang
College of Chemistry and Chemical Engineering, Jiangxi Normal
University, Nanchang, China
Abstract: Vinyl ethers were prepared with good yields in a one-pot, two-step trans-
formation by O-alkylation reaction of phenyl 2-hydroxyalkyl selenides with primary
or secondary organic halides followed by oxidation elimination with 30% hydrogen
peroxide.
Keywords: O-Alkylation, oxidation elimination, phenyl 2-hydroxyalkyl selenide,
vinyl ether
Vinyl ethers are valuable intermediates that can be used in a wide array of
chemical transformations[1] as well as vinyl polymer materials[2] containing
oxygen, which are expected to degrade easily in nature. Practically, vinyl
ethers are prepared by the reaction of acetylene with alcohols that was
developed by Reppe.[3] However, this reaction must be carried out under
severe conditions at higher pressure and temperature in the presence of
KOH as a catalyst. Several other methods are reported that prepare vinyl
and alkenyl ethers: for instance, mercury-catalyzed transvinylation of
alcohols with vinyl ethers,[4] elimination of the alcohol moiety or hydrogen
Received in Japan April 27, 2005
Address correspondence to Shou-Ri Sheng, College of Chemistry and Chemical
Engineering, Jiangxi Normal University, Nanchang, 330027, China. E-mail:
shengsr@163.com
2839

2840
S.-R. Sheng et al.
bromide from acetals or a-bromo ethers, respectively,[5,6] isomerization of
allyl ethers,[7] carbometalation of alkynic ethers,[8] and ester methylenation
promoted by metal complexes.[9] Recently, transformation with coupling of
vinyl acetate with alcohols promoted by iridium complexes[10] have also
been reported. However, most of these methods involved difficulties such as
harsh reactions, laborious manipulation, and low overall yields. In some
cases, reactions are unsuitable for sensitive substrates, vigorous toxic
compounds are used, or some reagents are not readily available. Organosele-
nium reagents are now commonly used as a powerful tool for introducing new
functional groups into organic substrates under extremely mild conditions.[11]
For example, phenylseleno group is readily converted to a leaving group,
giving access to carbon–carbon double bond via oxidation followed by
b-elimination. In continuation of our interest in organoselenium
chemistry,[12] we herein report a convenient and efficient one-pot, two-step
preparation of vinyl ethers from phenyl 2-hydroxyalkyl selenides by O-alky-
lation followed by oxidation elimination with 30% hydrogen peroxide
(Scheme 1).
Phenyl 2-hydroxyalkyl selenides (1a, 1b, and 1c) could be easily obtained
by the reaction of benzeneselenolate ions with the corresponding epoxides[13]
in ethanol at ambient temperature in 84%, 53%, and 90% yields, respectively.
With compounds 1a–1c in hand, the O-alkylation reaction was investigated
starting from phenyl 2-hydroxy-2-phenylethyl selenide (1a) with allyl
bromide (2a) in THF in the presence of sodium hydride, and 1a was easily
O-alkylated to afford phenyl 2-(allyloxy)-2-phenylethyl selenide[13d] (3a) in
87% yield without competing styrene oxide formation. As expected, 30%
hydrogen peroxide was added to the stirred solution of 3a in THF at 08C,
slowly resulting in a facile oxidation of the selenide to the corresponding
selenoxide, and then a syn-elimination of the selenoxide effected the release
of the 1-phenyl-1-(3-propenoxy)ethene (4a) in isolated 83% yield. Although
O-alkylated intermediate 3a can be isolated and purified by chromatography,
we have found it most convenient to carry out the oxidation elimination in
one-pot, which gives almost the same yield. To evaluate the scope of this
transformation, a variety of primary or allyl organic halides were subjected
to the reaction conditions. The results are outlined in Table 1 It is worth
noting the yields of vinyl ethers 4d and 4e (Entry 4 and 5) were relative
lower under the same reaction conditions, which may have resulted because
the corresponding O-prop-2-ynylation and O-isopropylation were effected in
Scheme 1.

Vinyl Ether Synthesis
2841
Table 1. One-pot synthesis of vinyl ethers from phenyl 2-hydroxyalkyl selenides
Entry
R1 (1)
C6H5 (1a)
R2R3CHX (2)
Product
Yield (%)a
1
2
3
4
5
6
CH255CHCH2Br (2a)
CH3CH2Br (2b)
CH3I (2c)
4a
4b
4c
4d
4e
4f
83
82
88
73
70
81
C6H5 (1a)
C6H5 (1a)
C6H5 (1a)
C6H5 (1a)
C6H5 (1a)
Propargyl bromide (2d)
(CH3)2CHBr (2e)
3-Cyclohexenyl
bromide (2f)
7
8
C6H5 (1a)
C6H5CH2Cl (2 g)
CH255CHCH2Br (2a)
CH3CH2Br (2b)
CH3CH2Br (2b)
4 g
4 h
4i
85
84
83
82
C6H5OCH2 (1b)
C6H5OCH2 (1b)
p-CH3C6H4OCH2 (1c)
9
10
4j
aIsolated yield based on phenyl 2-hydroxyalkyl selenides 1.
poorer yields than the other O-alkylations or O-allylations. On the other hand,
secondary halide (2e) may easily take place elimination under basic condition.
Further study on the reaction of 1a with tertiary halide such as t-butyl chloride
was examined. However, only 21% isolated yield of 1-tert-butoxy-1-pheny-
lethene (4 k) was obtained. Obviously, t-butyl chloride would tend to
mainly use the elimination reaction rather than the substitution reaction
under sodium alkylate. Additionally, on the basis of these results, an
attempt to synthesize of aryl vinyl ether, using phenyl bromide instead of
primary or secondary halides, resulted in almost no reaction using similar
procedures.
In summary, a facile one-pot procedure for the preparation of vinyl ethers
through O-alkylation of phenyl 2-hydroxyalkyl selenides with primary or
secondary organic halides and subsequent oxidation elimination has been
developed. The present method has advantages such as mild reaction con-
ditions, easy manipulation, and good yields.
EXPERIMENTAL
Melting points are uncorrected.1H NMR (400-MHz) spectra were recorded on
a Bruker Avance (400-MHz) spectrometer, using CDCl3 as the solvent and
TMS as internal standard. FT-IR spectra were taken on a Perkin-Elmer SP
One FT-IR spectrophotometer. Mass spectra (EI, 70eV) were recorded on a
HP5989B mass spectrometer. Microanalyses were performed with a PE
2400 elemental analyzer. Styrene oxide was commercially available and the
other two epoxides were prepared according to the literature procedure.[13]
Diphenyl diselenide[14] and phenyl 2-hydroxyalkyl selenides (1a and 1b are
compounds, 1c is unknown) were prepared according to the literature

2842
S.-R. Sheng et al.
methods.[15] THF was distilled under N2 from sodium/benzophenone immedi-
ately prior to use. Organic halides were obtained from commercial suppliers
and used without further purification. All reactions were monitored by TLC.
2-Hydroxy-3-(p-methylphenoxy)propyl phenyl selenide (1c): Light
yellow oil (yield: 90%);1H NMR: d ¼ 7.54–7.52 (m, 2H), 7.24–7.22 (m,
3H), 7.06 (d, J ¼ 8.4 Hz, 2H), 6.76 (d, J ¼ 8.4 Hz, 2H), 4.00 (dd, J ¼ 9.3,
4.2 Hz, 1H), 3.97 (dd, J ¼ 9.4, 5.8 Hz, 1H), 4.09–4.08 (m, 1H), 3.19 (dd,
J ¼ 12.8, 5.6 Hz, 1H), 3.14 (dd, J ¼ 12.8, 6.8 Hz, 1H), 2.81 (bs, 1H), 2.27
(s, 3H);13C NMR: d ¼ 156.3, 132.9, 130.5, 130.0, 129.4, 129.3, 127.3,
114.5, 70.7, 69.2, 31.9, 20.5; IR (film): n ¼ 3433, 3058, 2927, 2872, 1599,
1587, 1495, 1384, 1244, 1172, 1074, 1041, 941, 902, 814, 737, 669 cm21
.
MS m/z (relative intensity) 322 (Mþ, 5.1); anal. calcd. for C16H18O2Se: C,
59.82; H, 5.65. Found: C, 59.62; H, 5.68.
General Procedure for the Preparation of Vinyl Ethers
To a solution of phenyl 2-hydroxyalkyl selenide (1.0 mmol) in dry THF
(20 mL) at room temperature was added sodium hydride (0.04 g, 60% dis-
persion, 1.0 mmol). The resulting mixture was stirred for ca. 1 h at room tempe-
rature. A solution of the organic halide (1.0 mmol) in dry THF (2 mL) was then
added dropwise, and the reaction flask was placed in an oil bath preheated to
808C. The mixture was refluxed for 1 h and then cooled gradually to 08C. The
30% hydrogen peroxide (1.0 mL, 11.6 mmol) was added over 10 min. After an
additional stirring for 20 min at room temperature, water (20 mL) was added
and the solution was extracted with ether (20 ꢀ 3 mL). The combined
organic phase was washed with saturated NaHCO3 solution, brine, and
water (twice) and then dried over magnesium sulfate. The solvent was
removed in vacuo, and the residue was purified by flash silica-gel column
chromatography (CH2Cl2/hexane, 10 : 90) to give the pure product.
1-Phenyl-1-(3-propenoxy)ethene (4a):[9b] Colorless oil;1H NMR:
d ¼ 6.88–6.45 (m, 2H), 7.01–6.84 (m, 3H), 5.81–6.27 (m, 1H), 5.60–5.14
(m, 2H), 4.65 (d, J ¼ 3.1 Hz, 1H), 4.40–4.11 (m, 2H), 4.16 (d, J ¼ 3.1 Hz,
1H); IR (film): n ¼ 3056, 2974, 2850, 1645, 1622, 1595, 1495, 1242, 1100,
1044, 991, 912, 812 cm21
.
1-Ethoxy-1-phenylethene (4b):[9b] Colorless oil;1H NMR: d ¼ 7.68–
7.56 (m, 2H), 7.19–7.07 (m, 3H), 4.60 (d, J ¼ 2.1 Hz, 1H), 4.20
(d, J ¼ 2.1 Hz, 1H), 3.74 (q, J ¼ 7.1 Hz, 2H), 1.34 (t, J ¼ 7.1 Hz, 3H); IR
(film): n ¼ 3056, 2975, 2852, 1632, 1592, 1495, 1378, 1244, 1096, 1045,
990, 813 cm21
.
1-Methoxy-1-phenylethene (4c):[9b] Colorless oil;1H NMR: d ¼ 7.65–
7.52 (m, 2H), 7.18–7.04 (m, 3H), 4.58 (d, J ¼ 2.0 Hz, 1H), 4.21
(d, J ¼ 2.0 Hz, 1H), 3.71 (s, 3H); IR (film): n ¼ 3057, 2974, 2855, 1634,
1593, 1495, 1380, 1243, 1094, 1045, 988, 812 cm21
.

Vinyl Ether Synthesis
2843
1-Phenyl-1-(3-propynyloxy)ethene (4d): Colorless oil;1H NMR:
d ¼ 6.92–6.57 (m, 2H), 7.04–7.02 (m, 3H), 4.68 (d, J ¼ 3.0 Hz, 1H), 4.22
(d, J ¼ 3.0 Hz, 1H), 4.16 (dd, J ¼ 15.6, 2.4 Hz, 1H), 3.90 (dd, J ¼ 15.6,
2.4 Hz, 1H), 2.41 (t, J ¼ 2.4 Hz, 1H);13C NMR: d ¼ 158.7, 136.7, 132.1,
129.2, 126.8, 126.0, 80.1, 74.5, 56.7; IR (film): n ¼ 3280, 3059, 2972,
2851, 2212, 1636, 1595, 1495, 1354, 1245, 1102, 1044, 990, 910,
665 cm21; anal. calcd. for C11H10O: C, 83.52; H, 6.37. Found: C, 83.60; H,
6.43.
1-Isopropoxy-1-phenylethene (4e):[9b] Colorless oil;1H NMR: d ¼ 7.48–
7.21 (m, 2H), 7.10–7.01 (m, 3H), 4.56 (d, J ¼ 2.1 Hz, 1H), 4.25–4.32
(m, 1H), 4.03 (d, J ¼ 2.1 Hz, 1H), 1.32 (d, J ¼ 7.2 Hz, 6H); IR (film):
n ¼ 3058, 2976, 2845, 1635, 1558, 1495, 1384, 1375, 1240, 1101, 1042,
989, 810 cm21
.
1-(3-Cyclohexenoxy)-1-phenylethene (4f): Colorless oil;1H NMR:
d ¼ 7.77–7.73 (m, 2H), 7.15–7.06 (m, 3H), 5.94 (dd, J ¼ 10, 2.4 Hz, 1H),
5.70 (dt, J ¼ 10, 2.8 Hz, 1H), 4.75 (d, J ¼ 2.4 Hz, 1H), 4.56 (bs, 1H), 4.20
(d, J ¼ 2.4 Hz, 1H), 1.88–1.60 (m, 5H), 1.36–1.31 (m, 1H); 13C NMR:
d ¼ 158.9, 137.7, 131.3, 128.5, 128.3, 126.8, 126.0, 83.3, 70.4, 28.3, 25.3,
19.4; IR (film): n ¼ 3059, 2972, 2851, 1643, 1620, 1590, 1496, 1241, 1101,
1042, 978, 910, 810 cm21; anal. calcd. for C14H16O: C, 83.96; H, 8.05.
Found: C, 83.90; H, 8.15.
1-Benzoxy-1-phenylethene (4 g):[9b] Colorless oil;1H NMR: d ¼ 7.60–
7.01 (m, 10H), 4.81 (s, 2H), 4.52 (d, J ¼ 3.2 Hz, 1H), 4.12 (d, J ¼ 3.2 Hz,
1H); IR (film): n ¼ 3059, 2975, 2844, 1632, 1559, 1494, 1445, 1241, 1100,
1039, 985, 812 cm21
.
1-Phenoxymethyl-1-(3-propenoxy) ethene (4 h): Colorless oil;1H
NMR: d ¼ 6.95–6.86 (m, 2H), 7.27–7.20 (m, 3H), 5.94–5.84 (m, 1H),
5.25 (dd, J ¼ 17.2, 1.6 Hz, 1H), 5.15 (d, J ¼ 10.4 Hz, 1H), 4.12 (s, 2H),
4.09 (d, J ¼ 4.8 Hz, 2H), 3.15–3.26 (m, 2H);13C NMR: d ¼ 158.6, 134.7,
132.6, 129.2, 127.0, 121.0, 117.5, 114.6, 71.4, 29.3; IR (film): n ¼ 3060,
2923, 2856, 1622, 1600, 1495, 1244, 1096, 1079, 925, 814, 737, 691 cm21
anal. calcd. for C12H14O2: C, 75.76; H, 7.42. Found: C, 75.78; H, 7.51.
;
1-Ethoxy-1-phenoxymethylethene (4i): Colorless oil;1H NMR:
d ¼ 7.52–7.19 (m, 2 H), 6.86–7.00 (m, 3H), 4.08 (d, J ¼ 4.8 Hz, 2H), 3.59
(q, J ¼ 7.1 Hz, 2H), 3.26 (dd, J ¼ 12.8, 6.0 Hz, 1H), 3.23 (dd, J ¼ 12.8,
6.0 Hz, 1H), 1.18 (t, J ¼ 7.1 Hz, 3H);13C NMR: d ¼ 158.6, 132.5, 129.4,
126.9, 121.0, 114.6, 65.9, 29.5, 15.2; IR (film): n ¼ 3059, 2975, 2872,
1625, 1600, 1495, 1383, 1243, 1094, 1045, 882, 813, 691 cm21; anal. calcd.
for C11H14O2: C, 74.13; H, 7.92. Found: C, 74.08; H, 7.99.
1-Ethoxy-1-(p-methylphenoxymethyl) ethene (4j): Colorless oil;1H
NMR: d ¼ 7.52 (d, J ¼ 8.8 Hz, 2H), 6.77 (d, J ¼ 8.4 Hz, 2H), 4.06
(d, J ¼ 3.2 Hz, 2H), 3.60 (q, J ¼ 7.2 Hz, 2H), 3.24 (dd, J ¼ 12.8, 6.0 Hz,
1H), 3.17 (dd, J ¼ 12.8, 6.0 Hz, 1H), 2.31 (s, 3H), 1.17 (t, J ¼ 7.2 Hz,
3H);13C NMR: d ¼ 156.7, 132.6, 129.2, 127.2, 121.1, 114.5, 70.0, 29.6,
20.5, 15.3; IR (film): n ¼ 3057, 2975, 2871, 1624, 1600, 1494, 1385, 1244,

2844
S.-R. Sheng et al.
1095, 1045, 880, 812, 690 cm21; anal. calcd. for C12H16O2: C, 74.97; H, 8.39.
Found: C, 75.03; H, 8.44.
1-tert-Butoxy-1-phenylethene (4 k):[9b] Colorless oil;1H NMR:
d ¼ 7.44–7.19 (m, 2H), 7.12–6.95 (m, 3H), 4.65 (d, J ¼ 2.0 Hz, 1H), 4.28
(d, J ¼ 2.0 Hz, 1H), 1.34 (s, 9H); IR (film): n ¼ 3058, 2976, 2845, 1635,
1558, 1500, 1390, 1365, 1240, 1101, 1042, 990, 810 cm21
.
ACKNOWLEDGMENT
We are grateful for the financial support from the National Natural Science
Foundation of China and NSF of Jiangxi Province (No. 0420017).
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