Convenient synthesis of 1-(Trimethylsilyl)-and 1-(Trimethylstannyl) vinylphosphonates

Article abstract of DOI:10.1080/10426507.2013.855765

(Equation present) Dimethyl 1,1-bis(trimethylsilyl)methylphosphonate and dimethyl 1-(trimethylsilyl)-1-(trimethylstannyl)methylphosphonate were succeeded to react with aromatic aldehydes in the presence of methyl benzoate as additive to give the correspon

Full text of DOI:10.1080/10426507.2013.855765

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Phosphorus, Sulfur, and Silicon and the
Related Elements
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Convenient Synthesis of
1-(Trimethylsilyl)- and 1-
(Trimethylstannyl)vinylphosphonates
Yoshiharu Okadaa, Tomohiro Maruyamaa, Shin-ichi Tamuraa, Hirohito
Kameokaa, Satoshi Masudaa, Yuichiro Tokudaa, Junya Sakaia & Masato
Nomuraa
a Department of Biotechnology and Chemistry, Faculty of
Engineering, Kinki University, Umenobe 1, Takaya, 739-2116,
Higashi-Hiroshima, Japan
Accepted author version posted online: 23 Jan 2014.Published
online: 12 Jun 2014.
To cite this article: Yoshiharu Okada, Tomohiro Maruyama, Shin-ichi Tamura, Hirohito Kameoka,
Satoshi Masuda, Yuichiro Tokuda, Junya Sakai & Masato Nomura (2014) Convenient Synthesis of 1-
(Trimethylsilyl)- and 1-(Trimethylstannyl)vinylphosphonates, Phosphorus, Sulfur, and Silicon and the
Related Elements, 189:6, 778-790, DOI: 10.1080/10426507.2013.855765
To link to this article: http://dx.doi.org/10.1080/10426507.2013.855765
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Phosphorus, Sulfur, and Silicon, 189:778–790, 2014
Copyright ꢀC Taylor & Francis Group, LLC
ISSN: 1042-6507 print / 1563-5325 online
DOI: 10.1080/10426507.2013.855765
CONVENIENT SYNTHESIS OF 1-(TRIMETHYLSILYL)-
AND 1-(TRIMETHYLSTANNYL)VINYLPHOSPHONATES
Yoshiharu Okada, Tomohiro Maruyama, Shin-ichi Tamura,
Hirohito Kameoka, Satoshi Masuda, Yuichiro Tokuda,
Junya Sakai, and Masato Nomura
Department of Biotechnology and Chemistry, Faculty of Engineering, Kinki
University, Umenobe 1, Takaya, Higashi-Hiroshima 739-2116, Japan
GRAPHICAL ABSTRACT
O
CHO
SiMe3
O
O
O
O
LDA, methyl benzoate
THF, -70 ºC
(MeO)2P
SiMe3
+
P(OMe)2
O
SiMe3
4a
5e
(E)- or (Z)-6e
Abstract Dimethyl 1,1-bis(trimethylsilyl)methylphosphonate and dimethyl 1-(trimethylsilyl)-
1-(trimethylstannyl)methylphosphonate were succeeded to react with aromatic aldehydes in
the presence of methyl benzoate as additive to give the corresponding vinylphosphonates in
moderate yields.
Keywords Vinylphosphonates; vinylsilanes; Peterson reaction
INTRODUCTION
Organophosphorus, organosilicon, and organotin compounds are useful intermediates
for organic synthesis. Methylphosphonates with two phosphorus functional groups1 and
phosphorus and silicon functional groups2 are actively used in organic synthesis. However,
to the best our knowledge the derivatives with three functional groups are little investigated
so far. So, we became interested in the reactivity of multi-functionalized methylphospho-
nates toward carbonyl compounds. Furthermore, the vinylphosphonates obtained are useful
reagents in tandem reactions such as Michael reaction—Horner–Emmons–Woodwards
reaction.3 Here, we report on the convenient synthesis of vinylphosphonates with
trimethylsilyl and trimethylstannyl groups at α-position starting from multi-functionalized
methylphosphonates with trimethylsilyl and trimethylstannyl groups.
Received 29 April 2013; accepted 21 September 2013.
Address correspondence to Yoshiharu Okada, Department of Biotechnology and Chemistry, Fac-
ulty of Engineering, Kinki University, Umenobe 1, Takaya, Higashi-Hiroshima 739-2116, Japan. E-mail:
okadasan@hiro.kindai.ac.jp
Color versions of one or more of the figures in the article can be found online at www.tandfonline.com/gpss.
778

CONVENIENT SYNTHESIS OF 1-(TRIMETHYLSILYL)
779
RESULTS AND DISCUSSION
Dimethyl (trimethylsilyl)methylphosphonate (3a) and dimethyl (trimethylstannyl)-
methylphosphonate (3b) were prepared by an established procedure.2a Reaction of 3a,b
with chlorotrimethylsilane in the presence of LDA gave dimethyl 1,1-bis(trimethylsilyl)-
methylphosphonate (4a) and dimethyl 1-(trimethylsilyl)-1-(trimethylstannyl)methylphos-
phonate (4b) in 94% and 28% yield, respectively (Scheme 1).
Scheme 1
The reactions of 4a with carbonyl compounds 5a-k in the presence of LDA in THF
were carried out to give Peterson olefination products 6a-k (Equation (1)). The results are
summarized in Table 1.
(1)
The reaction of 4a with benzaldehyde 5a did not give the desired Peterson reaction
product 6a, only 4a was recovered (entry 1). Similar reaction in the presence of methyl
benzoate as an additive gave the mixture of (E)-6a and (Z)-6a. Preparative thin layer
chromatography (TLC) of these mixture afforded pure (E)-6a and (Z)-6a in 28% and 51%
yield, respectively (entry 2). Also sodium fluoride as an additive was effective (entry 3).
The structures of (E)-6a and (Z)-6a were assigned on the basis of their 1H, 13C, and
H,C HETCOR NMR spectra. Thus, the 1H-NMR spectrum of (E)-6a shows a signal for the
olefinic proton at 8.36 (d, J = 35.4 Hz), while that of (Z)-6a shows the respective signal
at 7.63 (d, J = 61.0 Hz). Minami and co-workers have reported that the olefinic protons
of diethyl (E)- and (Z)-2-(ethylthio)-1-(trimethylsilyl)vinylphosphonates were observed at
8.11 (d, 3JPH = 31.8 Hz) and 7.35 (d, 3JP-H = 55.6 Hz), respectively.4 Therefore, the larger
3
coupling constant was assigned to the anti JP-H. In order to confirm these assignments,
reactions of 4a with a variety of aromatic aldehydes were carried out (entries 4–8).
The reaction of 4a with piperonal 5e gave the mixture of (E)-6e and (Z)-6e. The
1H-NMR spectrum of (E)-6e shows a signal for the olefinic proton at 8.22 (d, J = 35.2 Hz),
while that of (Z)-6e shows the respective signal at 7.43 (d, J = 60.8 Hz).
Recrystallization of compound (Z)-6e from ether–hexane gave pure white
single crystals, suitable for X-ray diffraction. The X-ray analysis of (Z)-6e demon-
strated that the compound was indeed dimethyl (Z)-2-(3,4-methylenedioxyphenyl)-1-
(trimethylsilyl)vinylphosphonate (Figure 1).

780
Y. OKADA ET AL.
Table 1 Peterson reaction of 4a with carbonyl compounds 5a-k.1)

CONVENIENT SYNTHESIS OF 1-(TRIMETHYLSILYL)
781
Figure 1 ORTEP diagram of (Z)-6e.
In order to determine the limitation of this reaction, a similar reaction of 4a with
aliphatic aldehydes and ketones was carried out. Reaction of 4a with benzophenone, ace-
tophenone, and isobutyraldehyde did not occur because of steric hindrance and/or more
acidic protons (entries 9–14). However, 4a reacted with α,β-unsaturated aldehydes such as
crotonaldehyde, 4-methoxycinnamaldehyde, and pelliraldehyde in the presence of methyl
benzoate or sodium fluoride to give 6i-k in 46%–81% yields (entries 15–19). These results
indicate that the additive plays an important role in the activation of the silicon functional
group. Methyl benzoate seems to assist the Peterson reaction through a weak interaction
between silicon and oxygen. It was found that reaction of 4a with aromatic aldehydes gave
predominantly the Z-form of the corresponding vinylphosphonates, while similar reaction
with α,β-unsaturated aldehydes afforded mainly the E-form vinylphosphonates.
Next, the usage of a second functional group was investigated. Michael addition
and subsequent Peterson olefination reaction of 6e with 3,4,5-trimethoxyphenyllithium
and crotonaldehyde afforded the corresponding compound (2E,4E)-7 in 34% yield
(Equation (2)).5
(2)
Also the Peterson reaction of 1-(trimethylsilyl)-1-(trimethylstannyl)methyl
phosphonate 4b with aldehydes 5a,b,j was carried out and gave the corresponding mixture

782
Y. OKADA ET AL.
Table 2 Peterson reaction of 4b with carbonyl compounds 5a,b,j1)
of (E)- and (Z)-1-(trimethylstannyl)vinylphosphonates (E)- and (Z)-8a,b,j in moderate
yields (Equation (3)). The results are summarized in Table 2.
(3)
In this reaction, a similar tendency as in the case of 6a-k was observed. The reaction
of 4b with aromatic aldehydes afforded mainly (E)-1-(trimethylstannyl)vinylphosphonates,
while the corresponding reaction with an α,β-unsaturated aldehyde gave predominantly
(Z)-1-(trimethyl-stannyl)vinylphosphonate.
In conclusion, the multi-functionalized methylphosphonates 4a,b were useful for the
synthesis of 1-(trimethylsilyl)vinylphosphonate and 1-(trimethylstannyl)vinylphosphonate.
Reaction of 4a,b with aromatic aldehydes gave mainly the anti-isomers with respect to the
olefinic proton and the phosphonyl group. On the other hand, reaction of 4a,b with α,β-
unsaturated aldehydes gave predominantly the respective syn-isomers.
EXPERIMENTAL
1H, 13C, 29Si, and 31P NMR spectra were obtained with a JEOL JNM-EX400 spec-
trometer in CDCl3 operating at 400 MHz, 100 MHz, 79 MHz, and 160 MHz, respec-
tively, using Me4Si (1H, 13C, 29Si) and 85% H3PO4 (31P) as internal standards. IR spectra
were recorded with a Shimadzu FTIR-8100A instrument. X-ray diffraction data were
collected with a Rigaku XtaLAB mini diffractometer using graphite monochromated Mo-
Kα radiation (0.71075 Å). Melting points were measured in open capillary tubes and
are uncorrected. All reactions were carried out using degassed solvents under an argon
atmosphere.

CONVENIENT SYNTHESIS OF 1-(TRIMETHYLSILYL)
783
Tetrahydrofuran (THF) was purified by distillation over benzophenone ketyl under
an argon atmosphere before use.
Preparation of Dimethyl (Trimethylsilyl)methylphosphonate (3a)
and Dimethyl (Trimethylstannyl)methylphosphonate (3b)
A solution of dimethyl methylphosphonate 1 (12.4 g, 100 mmol) in THF (40 mL) was
added slowly to n-BuLi (1.65 M in hexane, 65.6 mL, 100 mmol) in THF (65 mL) at −70◦C
under argon atmosphere. After stirring for 15 min at the same temperature copper (I) iodide
(20.0 g, 100 mmol) was added to the mixture. The reaction mixture was warmed to −35 ◦C
and was stirred at −35◦C for 1 h. A solution of 2a,b (100 mmol) in THF (30 mL) was
added to the mixture at −35◦C. The reaction mixture was stirred for 12 h and was quenched
by the addition of water (100 mL). The mixture was filtered on celite pad, extracted with
diethyl ether and the organic layer was dried over anhydrous magnesium sulfate. The
solvent was removed in vacuo and the residue was distilled under reduced pressure to
give 3a,b.
Dimethyl (Trimethylsilyl)methylphosphonate (3a)
1
Yield: 12.5 g (64%). B.p.: 126–131◦C/45 mmHg. H NMR (CDCl3): δ = 0.09 (s,
9H, SiCH3), 1.07 (d, J = 22.0 Hz, 2H, CH2), 3.62 (d, J = 11.2 Hz, 6H, OCH3). 13C NMR
(CDCl3): δ = −0.30, 13.5 (d, J = 127.7 Hz), 52.0 (d, J = 6.6 Hz).
Dimethyl (Trimethylstannyl)methylphosphonate (3b)
1
Yield: 10.7 g (77%). B.p.: 80–85◦C/1.0 mmHg. H NMR (CDCl3): δ = −0.39 (s,
9H, CH3), 0.43 (d, J = 18.2 Hz, 2H, CH2), 3.02 (d, J = 11.0 Hz, 6H, OCH3). 13C NMR
(CDCl3): δ = −8.3, 4.5 (d, J = 133.4 Hz), 51.9 (d, J = 6.7 Hz).
Preparation of Dimethyl Bis(trimethylsilyl)methylphosphonate (4a)
and Dimethyl (Trimethylsilyl)(trimethylstannyl)methylphosphonate (4b)
To a solution of diisopropylamine (15.3 g, 90 mmol) in THF (120 mL) was added
n-BuLi (1.65 M in hexane, 125 mL, 90 mmol) at −70◦C under argon atmosphere. Af-
ter stirring for 15 min at the same temperature, a solution of 3a,b (90 mmol) in THF
(40 mL) was added to the mixture. After stirring for 15 min at the same temperature
chlorotrimethylsilane (14.8 mL, 90 mmol) was added to the mixture. The reaction mixture
was warmed to −35◦C and stirring was continued at −35◦C for 1 h. The reaction mixture
was stirred for 12 h at room temperature and was quenched by addition of 2 M hydrochloric
acid. The mixture was extracted with diethyl ether and the organic layer was dried over
anhydrous magnesium sulfate. The solvent was removed in vacuo and the residue was pu-
rified by vacuum distillation or column chromatography on silica gel (chloroform:diethyl
ether = 1:1) to give 4a,b.
Dimethyl Bis(trimethylsilyl)methylphosphonate (4a)
1
Yield: 22.35 g (93%). B.p.: 84–88◦C/0.3 mmHg. H NMR (CDCl3): δ = 0.14 (s,
18H, CH3), 0.65 (d, J = 25.1 Hz, 1H, CH), 3.64 (d, J = 11.0 Hz, 6H, OCH3). 13C NMR

784
Y. OKADA ET AL.
(CDCl3): δ = 1.30, 1.33, 15.8 (d, J = 107.0 Hz), 51.7 (d, J = 6.6 Hz). 29Si NMR (CDCl3):
δ = 0.8 (d, J = 6.8 Hz). 31P NMR (CDCl3): δ = 37.5 (s).
Dimethyl (Trimethylsilyl)(trimethylstannyl)methylphosphonate (4b)
Yield: 2.28 g (18%). 1H NMR (CDCl3): δ = 0.15–0.23 (m, 18H, CH3), 0.69 (d, J =
25.1 Hz, 1H, CH), 3.69 (d, J = 11.0 Hz, 6H, OCH3). 13C NMR (CDCl3): δ = 1.28, 1.31,
15.8 (d, J = 107.8 Hz, CH), 51.7 (d, J = 7.5 Hz, OCH3).
Reaction of 4a with Carbonyl Compounds 5a-k: General Procedure
To a solution of diisopropylamine (0.7 mL, 5.0 mmol) in THF (5 mL) was added n-
BuLi (1.65 M in hexane, 3 mL, 5.0 mmol) at −70◦C under argon atmosphere. After stirring
for 15 min at the same temperature, a solution of 4a (0.54 g, 2.0 mmol) in THF (5 mL) was
added to the mixture. After stirring for 15 min at the same temperature, a solution of the re-
spective carbonyl compound 5a-k (4 mmol) in THF (5 mL) was added to the mixture. After
stirring for 15 min at the same temperature, the additive (methyl benzoate (0.41 g, 3.0 mmol)
or sodium fluoride (0.10 g, 2.4 mmol)) was added to the mixture in one portion. The reaction
mixture was allowed to warm to room temperature and stirring was continued for 12 h. The
reaction mixture was quenched by the addition of 2M hydrochloric acid. The mixture was
extracted with diethyl ether and the organic layer was dried over anhydrous magnesium sul-
fate. The solvent was removed in vacuo and the residue was chromatographed on preparative
TLC (ethyl acetate:hexane = 2:3) to give compounds 6a-k. The results are summarized in
Table 1.
Dimethyl (E)-2-Phenyl-1-(trimethylsilyl)vinylphosphonate (E)-6a
Yield 0.16 g (28%). IR (neat): ν = 1581, 1244, 1030 cm−1. 1H NMR (CDCl3): δ =
0.06 (s, 9H, CH3), 3.78 (d, J = 11.0 Hz, 6H, OCH3), 7.24–7.35 (m, 5H, arom-H), 8.36
(d, J = 35.4 Hz, 1H, olefinic-H). 13C NMR (CDCl3): δ = 0.7 (d, J = 2.5 Hz), 52.2 (d,
J = 5.8 Hz), 127.76, 127.78, 127.9, 128.0, 128.4, 131.9 (d, J = 128.5 Hz), 138.5 (d, J =
29.9 Hz), 160.5. 29Si NMR (CDCl3): δ = −5.9 (d, J = 14.2 Hz).
Dimethyl (Z)-2-Phenyl-1-(trimethylsilyl)vinylphosphonate (Z)-6a
1
Yield 0.29 g (51%). IR (neat): ν = 1582, 1248, 1030 cm−1. H NMR (CDCl3):
δ = 0.29 (s, 9H, CH3), 3.49 (d, J = 11.2 Hz, 6H, OCH3), 7.32-7.38 (m, 3H, arom-H),
7.62 (d, J = 6.8 Hz, 1H, arom-H), 7.63 (d, J = 61.0 Hz, 1H, olefinic-H). 13C NMR
(CDCl3): δ = −0.5, 51.6 (d, J = 6.6 Hz), 127.2, 127.9, 128.8, 128.90, 128.92, 131.4 (d, J
= 138.5 Hz), 137.3 (d, J = 14.1 Hz), 156.1 (d, J = 2.5 Hz). 29Si NMR (CDCl3): δ = 1.7
(d, J = 15.1 Hz).
Dimethyl (E)-2-(4-Methylphenyl)-1-(trimethylsilyl)vinylphosphonate
(E)-6b
1
Yield 0.19 g (32%). IR (neat): ν = 1610, 1246, 1030 cm−1. H NMR (CDCl3): δ
= 0.08 (s, 9H, CH3), 2.37 (s, 3H, CH3), 3.76 (d, J = 11.0 Hz, 6H, OCH3), 7.16 (s, 4H,

CONVENIENT SYNTHESIS OF 1-(TRIMETHYLSILYL)
785
arom-H), 8.31 (d, J = 35.4 Hz, 1H, olefinic-H). 13C NMR (CDCl3): δ = 0.8 (d, J = 2.5 Hz),
21.3, 52.1 (d, J = 6.6 Hz), 127.99, 128.00, 128.6, 130.7 (d, J = 128.5 Hz), 135.5 (d, J =
29.9 Hz), 138.5, 160.7. 29Si NMR (CDCl3): δ = −6.2 (d, J = 13.7 Hz).
Dimethyl (Z)-2-(4-Methylphenyl)-1-(trimethylsilyl)vinylphosphonate
(Z)-6b
1
Yield 0.29 g (49%). IR (neat): ν = 1608, 1246, 1030 cm−1. H NMR (CDCl3):
δ = 0.27 (s, 9H, CH3), 2.36 (s, 3H, CH3), 3.51 (d, J = 11.2 Hz, 6H, OCH3),
7.16 (d, J = 7.8 Hz, 2H, arom-H), 7.54 (d, J = 61.3 Hz, 1H, olefinic-H), 7.55 (d, J =
8.1 Hz, 1H, arom-H). 13C NMR (CDCl3): δ = −0.5, 21.4, 51.6 (d, J = 5.8 Hz), 128.5,
129.6 (d, J = 138.5 Hz), 129.17, 129.19, 134.3 (d, J = 13.3 Hz), 139.1, 156.3 (d, J =
2.5 Hz). 29Si NMR (CDCl3): δ = 1.7 (d, J = 15.1 Hz).
Dimethyl 2-(4-Methoxyphenyl)-1-(trimethylsilyl)vinylphosphonate 6c
1
Yield 0.42 g (67%). H NMR (CDCl3): δ = 0.19 (s, 9H × 2/5, CH3), 0.26 (s, 9H
× 3/5, CH3), 3.53 (d, J = 11.2 Hz, 6H × 3/5, OCH3), 3.74 (d, J = 11.0 Hz, 6H × 2/5,
OCH3), 3.83 (s, 3H × 2/5, OCH3), 3.83 (s, 3H × 2/5, OCH3), 6.88–6.90 (m, 4H × 2/5,
arom-H), 7.25 (d, J = 8.5 Hz, 2H × 3/5, arom-H), 7.49 (d, J = 61.3 Hz, 1H × 3/5,
olefinic-H), 7.67 (d, J = 8.8 Hz, 2H × 3/5, arom-H), 8.27 (d, J = 35.4 Hz, 1H × 2/5,
olefinic-H).
Dimethyl 2-Pyrenyl-1-(trimethylsilyl)vinylphosphonate 6d
Yield 0.50 g (61%). 1H NMR (CDCl3): δ = −0.11 (s, 9H × 2/3, CH3), 0.45 (s, 9H
× 1/3, CH3), 3.28 (d, J = 13.2 Hz, 6H × 1/3, OCH3), 3.92 (d, J = 11.0 Hz, 6H × 2/3,
OCH3), 7.27–8.32 (m, 9H, arom-H), 8.41 (d, J = 60.5 Hz, 1H × 1/3, olefinic-H), 9.05 (d,
J = 34.9 Hz, 1H × 2/3, olefinic-H).
Dimethyl (E)-2-(3,4-methylenedioxyphenyl)-1-(trimethylsilyl)
vinylphosphonatet (E)-6e
1
Yield 0.14 g (21%). IR (neat): ν = 1568, 1238, 1030 cm−1. H NMR (CDCl3): δ
= 0.12 (s, 9H, CH3), 3.76 (d, J = 11.0 Hz, 6H, OCH3), 5.99 (s, 2H, CH2), 6.76 (d, J =
9.5 Hz, 2H, arom-H), 6.79 (s, 1H, arom-H), 8.22 (d, J = 35.2 Hz, 1H, olefinic-H). 13C
NMR (CDCl3): δ = 0.8 (d, J = 2.5 Hz), 52.1 (d, J = 5.8 Hz), 101.2, 107.81, 108.4, 122.5
(d, J = 1.7 Hz), 130.2 (d, J = 129.4 Hz), 132.2 (d, J = 29.9 Hz), 147.3, 147.9, 160.0. 29Si
NMR (CDCl3): δ = −6.4 (d, J = 13.7 Hz).
Dimethyl (Z)-2-(3,4-methylenedioxyphenyl)-1-(trimethylsilyl)
vinylphosphonate (Z)-6e
Yield 0.28 g (42%). M.p. 85–88◦C (from Et2O/hexane). IR (KBr): ν = 1570, 1240,
1
1032 cm−1. H NMR (CDCl3): δ = 0.41 (s, 9H, CH3), 3.56 (d, J = 11.2 Hz, 6H,
OCH3), 5.99 (s, 2H, CH2), 6.80 (d, J = 8.1 Hz, 1H, arom-H), 7.15 (dd, J = 1.7 Hz,
8.1 Hz, 1H, arom-H), 7.31 (d, J = 1.7 Hz, 1H, arom-H), 7.43 (d, J = 60.8 Hz, 1H,

786
Y. OKADA ET AL.
olefinic-H). 13C NMR (CDCl3): δ = −0.4, 51.6 (d, J = 5.8 Hz), 101.2, 107.6, 109.4
(d, J = 1.7 Hz), 124.7 (d, J = 2.5 Hz), 128.4 (d, J = 137.7 Hz), 131.2 (d, J =
13.3 Hz), 147.2, 148.3, 155.7 (d, J = 2.5 Hz). 29Si NMR (CDCl3): δ = 2.0 (d, J =
15.1 Hz). Crystal system: Monoclinic; Space group: P21/n, a = 6.625(3) Å, b = 7.127(3)
Å, c = 34.852(16) Å, β = 91.045(4)◦, V = 1645.3(13) Å3, Z = 4, R1 = 0.0512,
wR = 0.1320.
Dimethyl (1E,3E)-1-(Trimethylsilyl)-1,3-pentadienylphosphonate
(1E,3E)-6i
1
Yield 0.31 g (62%). IR (neat): ν = 1637, 1250, 1028 cm−1. H NMR (CDCl3):
δ = 0.26 (s, 9H, CH3), 1.89 (d, J = 6.8 Hz, 3H, CH3), 3.68 (d, J = 11.0 Hz, 6H, OCH3),
6.17 (sext, J = 6.8 Hz, 1H, olefinic-H), 6.24–6.49 (m, 1H, olefinic-H), 7.63 (dd, J =
11.5 Hz, 33.7 Hz, 1H, olefinic-H). 13C NMR (CDCl3): δ = 0.6 (d, J = 2.5 Hz), 18.8, 51.9
(d, J = 5.8 Hz), 125.0 (d, J = 137.7 Hz), 130.1 (d, J = 31.5 Hz), 141.5, 159.0. 29Si NMR
(CDCl3): δ = −7.1 (d, J = 14.6 Hz).
Dimethyl (1Z,3E)-1-(Trimethylsilyl)-1,3-pentadienylphosphonate
(1Z,3E)-6i
Yield 0.11 g (22%). IR (neat): 1635, 1248, 1028 cm−1. 1H NMR (CDCl3): δ = 0.19
(s, 9H, CH3), 1.89 (d, J = 6.6 Hz, 3H, CH3), 3.69 (d, J = 11.0 Hz, 6H, OCH3), 6.10 (sext,
J = 6.8 Hz, 1H, olefinic-H), 6.94–7.12 (m, 2H, olefinic-H). 13C NMR (CDCl3): δ = −0.8,
18.6, 51.6 (d, J = 5.8 Hz), 125.1 (d, J = 135.2 Hz), 130.6 (d, J = 14.1 Hz), 140.7, 156.9.
29Si NMR (CDCl3): δ = −0.3 (d, J = 15.6 Hz).
Dimethyl (1E,3E)-4-(4-Methoxyphenyl)-1-(trimethylsilyl)-1,3-
butadienylphosphonate (1E,3E)-6j
1
Yield 0.39 g (57%). IR (neat): ν = 1601, 1248, 1028 cm−1. H NMR (CDCl3):
δ = 0.32 (s, 9H, CH3), 3.71 (d, J = 11.0 Hz, 6H, OCH3), 3.84 (s, 3H, OCH3),
6.86 (d, J = 15.4 Hz, 1H, olefinic-H), 6.90 (d, J = 8.8 Hz, 2H, arom-H), 7.02 (ddd,
J = 2.4 Hz, 11.5 Hz, 14.9 Hz, 1H, olefinic-H), 7.39 (d, J = 8.5 Hz, 2H, arom-
H), 7.80 (dd, J = 11.5 Hz, 33.0 Hz, 1H, olefinic-H). 13C NMR (CDCl3): δ = 0.8
(d, J = 2.5 Hz), 51.9 (d, J = 5.8 Hz), 55.3, 114.2, 124.2 (d, J = 31.5 Hz), 126.2
(d, J = 138.5 Hz), 128.7, 141.8, 158.6, 160.4. 29Si NMR (CDCl3): δ = −6.9 (d,
J = 14.2 Hz).
Dimethyl (1Z,3E)-4-(4-Methoxyphenyl)-1-(trimethylsilyl)-1,3-
butadienylphosphonate (1Z,3E)-6j
1
Yield 0.19 g (28%). IR (neat): ν = 1603, 1248, 1030 cm−1. H NMR (CDCl3):
δ = 0.22 (s, 9H, CH3), 3.71 (d, J = 11.2 Hz, 6H, OCH3), 3.83 (s, 3H, OCH3), 6.77 (d, J =
15.4 Hz, 1H, olefinic-H), 6.88 (d, J = 8.5 Hz, 2H, arom-H), 7.21 (dd, J = 9.3 Hz, 59.6 Hz,
1H, olefinic-H), 7.46 (d, J = 8.8 Hz, 2H, arom-H), 7.69 (dd, J = 11.2 Hz, 14.4 Hz, 1H,
olefinic-H). 13C NMR (CDCl3): δ = 0.7, 52.3 (d, J = 5.8 Hz), 56.0, 114.7, 125.6 (d, J =

CONVENIENT SYNTHESIS OF 1-(TRIMETHYLSILYL)
787
17.1 Hz), 127.0 (d, J = 135.2 Hz), 129.5, 129.6, 141.8 (d, J = 2.2 Hz), 157.4, 160.9. 29Si
NMR (CDCl3): δ = −0.2 (d, J = 15.1 Hz).
(Z)-4-Isopropenyl-1-(2-(dimethylphosphono)-2-(trimethylsilylvinyl))
cyclohexene (Z)-6k
Yield 0.16 g (24%). 1H NMR (CDCl3): δ = 0.20 (s, 9H, CH3), 1.43–1.53 (m, 1H),
1.74 (s, 3H, CH3), 1.88 (d, J = 14.2 Hz, 1H, CH2), 2.09–2.34 (m, 5H, CH2 and CH), 3.66
(d, J = 11.2 Hz, 6H, OCH3), 4.73 (d, J = 8.1 Hz, 2H, CH2), 6.16 (s, 1H, olefinic-H), 6.93
(d, J = 61.5 Hz, 1H, olefinic-H).
(E)-4-Isopropenyl-1-(2-(dimethylphosphono)-2-(trimethylsilylvinyl))
cyclohexene (E)-6k
1
Yield 0.12 g (18%). H NMR (CDCl3): δ = 0.21 (s, 9H, CH3), 1.42–1.53 (m, 1H,
CH2), 1.76 (s, 3H, CH3), 1.87 (d, J = 12.5 H, 1H, CH2), 2.02–2.33 (m, 5H, CH2 and CH),
3.72 (d, J = 11.0 Hz, 6H, OCH3), 4.74 (d, J = 9.3 Hz, 2H, CH2), 5.70 (s, 1H, olefinic-H),
7.61 (d, J = 34.7 Hz, 1H, olefinic H).
Michael Addition and Peterson Tandem Reaction of 6d
To a solution of 1-bromo-3,4,5-trimethoxybenzene (0.08 g, 0.3 mmol) in THF (3 mL)
was added n-BuLi (1.65 M in hexane, 0.2 mL, 0.3 mmol) at −70◦C under argon atmosphere.
After stirring for 15 min at the same temperature a solution of 6e (0.10 g, 0.3 mmol) in THF
(3 mL) was added to the mixture. After being stirring for further 15 min at the same temper-
ature a solution of crotonaldehyde (0.03 g, 0.4 mmol) in THF (2 mL) was added to the mix-
ture. The reaction mixture was warmed to room temperature and stirring was continued for
2 h. The reaction mixture was quenched by the addition of 2 M hydrochloric acid. The mix-
ture was extracted with diethyl ether and the organic layer was dried over anhydrous mag-
nesium sulfate. The solvent was removed in vacuo and the residue was chromatographed
on preparative TLC (ethyl acetate:hexane = 2:3) to give 0.05 g of compound 7 (34%
yield).
(2E,4E)-1-(3,4,5-Trimethoxyphenyl)-1-(3,4-methylenedioxyphenyl)-2-
(dimethylphosphono)- hexa-2,4-diene ((2E,4E)-7)
1H NMR (CDCl3): δ = 1.68 (d, J = 6.1 Hz, 3H, CH3), 3.51 (d, J = 11.0 Hz, 3H,
OCH3), 3.57 (d, J = 11.0 Hz, 3H, OCH3), 3.76 (s, 6H, OCH3), 3.85 (s, 3H, OCH3), 5.15
(d, J = 17.1 Hz, 1H, CH), 5.93–6.07 (m, 2H, olefinic-H), 5.96 (s, 2H, CH2), 6.43 (s, 2H,
arom-H), 6.60 (dd, J = 1.0 Hz, 8.1 Hz, 1H, arom-H), 6.68 (d, J = 1.7 Hz, 1H, arom-H),
6.74 (d, J = 8.1 Hz, 1H, arom-H), 7.23 (dd, J = 10.5 Hz, 24.2 Hz, 1H, olefinic-H). 13C
NMR (CDCl3): δ = 18.8, 49.6 (d, J = 10.8 Hz), 52.1 (d, J = 5.0 Hz), 55.9, 60.8, 100.7,
106.1, 107.6, 109.2, 121.8, 126.8 (d, J = 179.3 Hz), 127.2 (d, J = 23.3 Hz), 135.7 (d,
J = 6.6 Hz), 136.3, 137.0 (d, J = 6.6 Hz), 139.7, 145.7 (d, J = 4.1 Hz), 145.9, 147.3,
152.6.

788
Y. OKADA ET AL.
Reaction of 4b With Carbonyl Compounds 5a,b,j
To a solution of diisopropylamine (0.7 mL, 5.0 mmol) in THF (5 mL) was added
n-BuLi (1.65 M in hexane, 3 mL, 5.0 mmol) at −70◦C under argon atmosphere. Af-
ter stirring for 15 min at the same temperature a solution of 4b (0.72 g, 2.0 mmol) in
THF (5 mL) was added to the mixture. After stirring for further 15 min at the same
temperature a solution of the respective carbonyl compound 5a,b,j (4.0 mmol) in THF
(5 mL) was added to the mixture and stirring was continued for 15 min at the same
temperature. Sodium fluoride (0.10 g, 2.4 mmol) was added to the mixture one portion.
The reaction mixture was warmed to room temperature and stirring was continued for
12 h. The reaction mixture was quenched by the addition of 2 M hydrochloric acid.
The mixture was extracted with diethyl ether and the organic layer was dried over an-
hydrous magnesium sulfate. The solvent was removed in vacuo, and the residue was
chromatographed on preparative TLC (chloroform:diethyl ether = 9:1) to give compounds
8a,b,j.
Dimethyl (E)-2-Phenyl-1-(trimethylstannyl)vinylphosphonate (E)-8a
Yield 0.22 g (29%). 1H NMR (CDCl3): δ = 0.28 (s, 9H, CH3), 3.49 (d, J = 11.2 Hz,
6H, OCH3), 7.30–7.39 (m, 3H, arom-H), 7.58 (d, J = 61.0 Hz, 1H, olefinic-H), 7.62 (dd,
J = 1.7 Hz, 8.1 Hz, 2H, arom-H). 13C NMR (CDCl3): δ = −0.5, 51.6 (d, J = 6.6 Hz),
127.8, 128.85 (d, J = 8.3 Hz), 128.9, 131.3 (d, J = 137.7 Hz), 137.3 (d, J = 13.3 Hz),
156.2 (d, J = 2.5 Hz).
Dimethyl (Z)-2-Phenyl-1-(trimethylstannyl)vinylphosphonate (Z)-8a
Yield 0.10 g (13%). 1H NMR (CDCl3): δ = 0.06 (s, 9H, CH3), 3.77 (d, J = 10.7 Hz,
6H, OCH3), 7.23–7.27 (m, 2H, arom-H), 7.32–7.36 (m, 3H, arom-H), 8.35 (d, J = 35.6 Hz,
1H, olefinic-H). 13C NMR (CDCl3): δ = 0.7 (d, J = 2.5 Hz), 52.2 (d, J = 6.6 Hz),
127.8 (d, J = 1.7 Hz), 127.9, 128.4, 131.8 (d, J = 129.4 Hz), 138.4 (d, J = 29.9 Hz),
160.5.
Dimethyl (E)-2-(4-Methylphenyl)-1-(trimethylstannyl)vinylphosphonate
(E)-8b
1
Yield 0.24 g (31%). H NMR (CDCl3): δ = 0.27 (s, 9H, CH3), 2.35 (s, 3H, CH3),
3.50 (d, J = 11.2 Hz, 6H, OCH3), 7.16 (d, J = 7.8 Hz, 2H, arom-H), 7.54 (d, J = 61.3 Hz,
1H, olefinic-H), 7.55 (d, J = 8.1 Hz, 2H, arom-H). 13C NMR (CDCl3): δ = −0.6, 21.3,
51.5 (d, J = 6.6 Hz), 126.7, 128.4, 128.9 (d, J = 36.5 Hz), 129.1, 134.1 (d, J = 13.3 Hz),
137.4 (d, J = 187.4 Hz), 139.0, 156.3 (d, J = 2.5 Hz).
Dimethyl (Z)-2-(4-Methylphenyl)-1-(trimethylstannyl)vinylphosphonate
(Z)-8b
Yield 0.19 g (24%). 1H NMR (CDCl3): δ = 0.09 (s, 9H, CH3), 2.36 (s, 3H, CH3), 3.76
(d, J = 11.0 Hz, 6H, OCH3), 7.16 (s, 4H, arom-H), 8.32 (d, J = 35.4 Hz, 1H, olefinic-H).
13C NMR (CDCl3): δ = 0.8 (d, J = 2.5 Hz), 21.3, 52.1 (d, J = 5.8 Hz), 128.0 (d, J =

CONVENIENT SYNTHESIS OF 1-(TRIMETHYLSILYL)
789
1.7 Hz), 128.5, 130.6 (d, J = 129.4 Hz), 135.4 (d, J = 29.9 Hz), 138.5, 160.7 (d, J =
1.7 Hz).
(1E,3E)-4-(4-Methoxyphenyl)-1-(dimethylphosphono)-1-
trimethylstannyl-1,3-butadiene (1E,3E)-8j
Yield 0.20 g (23%). 1H NMR (CDCl3): δ = 0.22 (s, 9H, CH3), 3.71 (d, J = 11.2 Hz,
6H, OCH3), 3.83 (s, 3H, OCH3), 6.77 (d, J = 15.4 Hz, 1H, olefinic-H), 6.88 (d, J = 8.5 Hz,
2H, arom-H), 7.21 (dd, J = 11.0 Hz, 59.6 Hz, olefinic-H), 7.46 (d, J = 8.5 Hz, 2H, arom-H),
7.69 (dd, J = 11.0 Hz, 15.4 Hz, 1H, olefinic-H). 13C NMR (CDCl3): δ = −0.7, 51.6 (d,
J = 5.8 Hz), 55.3, 114.0, 124.9 (d, J = 14.1 Hz), 126.2 (d, J = 136.0 Hz), 128.8, 128.9,
141.1 (d, J = 2.5 Hz), 156.7, 160.2.
(1Z,3E)-4-(4-Methoxyphenyl)-1-(dimethylphosphono)-1-
trimethylstannyl-1,3-butadiene (1Z,3E)-8j
Yield 0.39 g (45%). 1H NMR (CDCl3): δ = 0.32 (s, 9H, CH3), 3.71 (d, J = 11.0 Hz,
6H, OCH3), 3.84 (s, 3H, OCH3), 6.86 (d, J = 15.1 Hz, 1H, olefinic-H), 6.91 (d, J = 8.8 Hz,
2H, arom-H), 7.02 (ddd, J = 2.7 Hz, 11.2 Hz, 15.1 Hz, olefinic-H), 7.39 (d, J = 8.5 Hz,
2H, arom-H), 7.81 (dd, J = 11.2 Hz, 32.7 Hz, 1H, olefinic-H). 13C NMR (CDCl3): δ = 0.8
(d, J = 2.5 Hz), 51.9 (d, J = 5.8 Hz), 55.3, 114.2, 124.2 (d, J = 31.5 Hz), 126.2 (d, J =
137.7 Hz), 128.6, 128.7, 141.8, 158.6, 160.3.
ACKNOWLEDGMENT
We thank Mr. T. Matsumoto (Rigaku Co.) for X-ray analysis.
SUPPLEMENTAL MATERIAL
Supplementary data of this article can be accessed on the publisher’s website,
www.tandfonline.com/gpss
REFERENCES
1. (a) Smith, P. W.; Chamiec, A. J.; Chung, G.; Cobley, K. N.; Duncan, K.; Howes, P. D.; Whit-
tington, A. R.; Wood, M. R. J. Antibiotics 1995, 48, 73-82. (b) Iorga, B.; Eymery, F.; Savignac,
P. Tetrahedron Lett. 1998, 39, 4477-4480. (c) Borodkin, V. S.; Ferguson, M. S. J.; Nikolaev, A.
V. Tetrahedron Lett. 2001, 42, 5305-5308. (d) Zgani, I.; Menut, C.; Monte´ro, J. L. Heteroatom
Chem. 2002, 13, 654-661. (e) Ronchi, S.; Compostella, F.; Lay, L.; Ronchetti, F.; Toma, L. Eur.
J. Org. Chem. 2005, 4459-4463. (f) Watkins, W. J.; Chen, J. M.; Cho, A.; Chong, L.; Collins,
N.; Fardis, M.; Huang, W.; Hung, M.; Kirschberg, T.; Lee, W. A.; Liu, X.; Thomas, W.; Xu, J.;
Zeynalzadegan, A.; Zhang, J. Bioorg. Med. Lett. 2006, 16, 3479-3483. (g) Bortolini, O.; Mulani,
I.; De Nino, A.; Maiuolo, L.; Nardi, M.; Russo, B.; Avnet, S. Tetrahedron 2011, 67, 5635-5641.
2. (a) Savignac, P.; Mathey, F. Synthesis, 1982, 725-726. (b) Kawashima, T.; Ishii, T.; Inamoto, N.
Tetrahedron Lett. 1983, 24, 739-742. (c) Aboujaoude, E. E.; Lietje, S.; Collignon, N.; Teulade,
M. P.; Savignac, P. Synthesis 1986, 934-937. (d) Savignac, P.; Teulade, M. P.; Collignon, N. J.
Orgnomet. Chem. 1987, 323, 135-144. (e) Kawashima, T.; Ishii, T.; Inamoto, N. Bull. Chem.
Soc. Jpn. 1987, 60, 1831-1837. (f) Umezawa, T.; Seino, T.; Matsuda, F. Org. Lett. 2012, 14,
4206-4209.

790
Y. OKADA ET AL.
3. For a review on synthetic uses of vinylphosphonates, see: Minami, T.; Motoyoshiya, J. Synthesis
1992, 333-349.
4. Kouno, R.; Okauchi, T.; Nakamura, M.; Ichikawa, J.; Minami, T. J. Org. Chem. 1998, 63,
6239-6246.
5. Chang, K.; Ku, B.; Oh, D. Y. Synth.Commun. 1989, 19, 1891-1898.