Synthesis of Allenylphosphonates through Cu(I)-Catalyzed Coupling of Terminal Alkynes with Diazophosphonates

Article abstract of DOI:10.1055/s-0035-1561298

Through the Cu(I)-catalyzed coupling of diazophosphonates with terminal alkynes, an efficient method for the synthesis of allenylphosphonates has been developed. Simple and inexpensive CuI is used as the catalyst and the reaction is conducted under mild conditions.

Full text of DOI:10.1055/s-0035-1561298

SYNTHESIS
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© Georg Thieme Verlag Stuttgart · New York
2016, 48, 751–760
paper
751
C. Wu et al.
Paper
Synthesis
Synthesis of Allenylphosphonates through Cu(I)-Catalyzed
Coupling of Terminal Alkynes with Diazophosphonates
Chenggui Wua,b
Fei Yeb
Guojiao Wub
Shuai Xub
(MeO)2OP
R
PO(OMe)2
Ar
CuI (20 mol%)
N2
•
i-Pr2NH (1.0 equiv)
R
+
Ar
1,4-dioxane, 80 °C, 3 h
Guisheng Deng*a
Yan Zhangb
Jianbo Wang*b
22 examples; 52–98%
a College of Chemistry and Chemical Engineering, Hunan
Normal University, Changsha 410081, P. R. of China
gsdeng@hunnu.edu.cn
b Key Laboratory of Bioorganic Chemistry and Molecular Engi-
neering of Ministry of Education, College of Chemistry, Peking
University, Beijing 100871, P. R. of China
wangjb@pku.edu.cn
Received: 15.10.2015
Accepted after revision: 26.11.2015
Published online: 04.01.2016
O
Ph
Ph
•
P
O
DOI: 10.1055/s-0035-1561298; Art ID: ss-2015-h0611-op
R1
R2
P(OEt)2
•
Abstract Through the Cu(I)-catalyzed coupling of diazophosphonates
with terminal alkynes, an efficient method for the synthesis of allenyl-
phosphonates has been developed. Simple and inexpensive CuI is used
as the catalyst and the reaction is conducted under mild conditions.
Me
1
DNA cleavage and antitumor activity
Key words diazophosphonate, allene, cross-coupling, carbene, cop-
per
MeO
2
G6PDH: inhibitors for the glucose-
6-phosphate dehydrogenase
Due to the characteristics of two perpendicular π-
bonds, the chemistry of allenes has emerged as a bourgeon-
ing research topic in organic chemistry and other related
areas, such as pharmaceutical research.1,2 Among the allene
structural units that have been widely discovered in natural
products and pharmaceuticals,1,3 allenylphosphonates play
an especially important role in biological and medicinal
chemistry. Besides, because of the electron-withdrawing
nature of the phosphonate group, allenylphosphonates are
found to be potentially useful synthetic intermediates.4 The
prominent reactivity features of this type of allene com-
pounds are: 1) selective addition of various N-, O-, and S-
nucleophiles;5–7 2) selective total or partial hydrogena-
tion;8,9 3) radical reactions;10 and 4) Diels–Alder reaction
and other cycloadditions.11,12 In addition, a number of com-
pounds containing allenylphosphonates show interesting
biological activities.13 For example, allene 1 shows DNA
cleavage and antitumor activity14 and G6PDH (2) is an in-
hibitor for the glucose-6-phosphate dehydrogenase3a (Fig-
ure 1).
Figure 1 Biologically active allenes
On account of their wide applications in various fields, it
is highly desirable to develop efficient methods for the syn-
thesis of allenylphosphonates.
The synthetic methods for allenylphosphonates docu-
mented in the literature are summarized in Scheme 1. The
first method generates allenylphosphonates via [2,3]-sig-
matropic rearrangement of propargyl phosphates, which
are easily obtained from the corresponding propargylic al-
cohols (Scheme 1, a).15 Although the substrate scope of
propargylic alcohols is wide, the corresponding phosphates
that can be derived by simple nucleophilic reaction with
phosphorochloridates is rather limited. The second method
that has attracted significant attention in allenylphospho-
nate synthesis is based on the transition-metal-catalyzed
propargylic substitution (SN2′) reaction (Scheme 1, b).16 The
reaction affords the allenylphosphonate products in good
yields with wide substrate scope. However, the reaction re-
quires complex ligands, and the by-products are usually not
easy to separate, which significantly limits the practical ap-
plication of this method.
© Georg Thieme Verlag Stuttgart · New York — Synthesis 2016, 48, 751–760

752
C. Wu et al.
Paper
Synthesis
Table 1 Optimization of Reaction Conditionsa
RO
OR
O
O
OH
R2
P
R2
R3
P
OR
(RO)2PCl
cat. CuI
i-Pr2NH
N2
Ph
R1
O
OR
(a)
(b)
•
R2
R1
•
R3
Ph
+
PO(OMe)2
R1
Ph
(MeO)2OP
Ph
1,4-dioxane,
R3
80–90 °C, 3 h
3a
4a
5a
R5
R4
R1
R2
P
X
R1
O
P
H
Entry 3a (equiv) Cat. (mol%) Base (mol%)
Temp (°C) Yield (%)b
cat. Pd(0)
R5
R3
R4
+
•
R3
R2
1
2
3
4
5
6
1.2
1.2
1.3
1.3
1.3
1.3
CuI (20)
CuI (20)
CuI (20)
CuI (10)
CuI (20)
CuI (20)
i-Pr2NH (100) 90
72
82
85
75
70
75
i-Pr2NH (100) 80
i-Pr2NH (100) 80
i-Pr2NH (100) 80
this work
R1
N2
O
•
cat. Cu(I)
RO
R2
R2
R1
+
P
P
(c)
i-Pr2NH (20)
i-Pr2NH (60)
80
80
OR
RO
O
RO
Scheme1 Synthetic strategies towards allenylphosphonates
aReaction conditions: 3a, 4a (0.2 mmol), CuI, and i-Pr2NH in 1,4-dioxane (1
mL) under an N2 atmosphere for 3 h.
b Isolated yields by column chromatography.
Recently, we and others have developed a novel method
for the allene synthesis based on the copper(I)-catalyzed
cross-coupling of N-tosylhydrazones or diazo compounds
with terminal alkynes.17 In view of the importance of allen-
ylphosphonates, we have conceived that a similar cop-
per(I)-catalyzed cross-coupling of terminal alkynes with di-
azophosphonates may serve as a novel approach for the
synthesis of allenylphosphonates. Herein we report our
studies along these lines (Scheme 1, c).
CuI (20 mol%)
Ph
N2
i-Pr2NH (1 equiv)
•
R
+
(MeO)2OP
R
1,4-dioxane, 80 °C,
3 h
Ph
PO(OMe)2
3a
4b–n
5b–n
5b, X = Me, 90%
5c, X = OMe, 98%
5d, X = NMe2, 57%
5e, X = Cl, 86%
Ph
Ph
•
The study began with the evaluation of the feasibility of
the reaction between dimethyl [diazo(phenyl)methyl]phos-
phonate (3a) and phenylacetylene (4a), with CuI as the cat-
alyst, i-Pr2NH as the base, and 1,4-dioxane as the solvent
(Table 1). The desired product 5a was obtained in 72% yield
at 90 °C (Table 1, entry 1). Slightly lowering the reaction
temperature to 80 °C improved the yield to 82% (entry 2).
The yield was further enhanced when the amount of 3a was
slightly increased (entry 3). Attempts to reduce either the
catalyst loading or the amount of base led to diminished
yields, although the reaction still proceeded smoothly to
give moderate yields of the allene product (entries 4–6).
With the optimized reaction conditions in hand, the
scope of this reaction was then explored with a series of di-
azophosphonates and terminal alkynes. First, the scope of
terminal alkynes was examined through the reaction with
diazophosphonate 3a (Scheme 2). Under identical reaction
conditions, the reactions afforded the corresponding allene
products 5b–n in good yields. It is noteworthy that the re-
actions were not significantly affected by the substituents
on the aromatic ring in terminal alkynes 4b–i. Moreover,
the reaction also worked with terminal alkynes bearing
substituents such as heterocycle 5j, alkenyl 5k, and alkyl 5l,
5m. In particular, a substrate containing an unprotected hy-
droxyl group was applied in the synthesis of 5m. Interest-
ingly, when the alkyne bearing TIPS (triisopropylsilyl) sub-
stituent was subjected to the reaction, the main product
was the internal alkyne 5n′, instead of the allene product.
The ratio of alkyne 5n′ and the minor product allene 5n was
•
Cl
(MeO)2OP
(MeO)2OP
5f, X = Br, 80%
5g, X = CF3, 70%
5h, 78%
X
Ph
Ph
•
•
(MeO)2OP
(MeO)2OP
S
5j, 56%
5i, 95%
OMe
Ph
•
Ph
Ph
(MeO)2OP
(MeO)2OP
•
•
(MeO)2OP
OH
5l, 80%
Me
5m, 62%a
5k, 95%
Ph
Ph
•
TIPS
+
(MeO)2OP
TIPS
(MeO)2OP
5n'
5n
68%b (5n':5n = 10:1)
Scheme 2 The substrate scope of terminal alkynes. Reaction condi-
tions: 3a (1.3 equiv), terminal alkynes 4b–n (0.2 mmol), CuI (20 mol%),
i-Pr2NH (1.0 equiv) in 1.4-dioxane (1 mL) under N2 at 80 °C for 3 h; iso-
lated yields by column chromatography. a Diastereomeric ratio (dr): 1:1.
b Overall yield of 5n and 5n′. Ratio of 5n′/5n: 10:1.
© Georg Thieme Verlag Stuttgart · New York — Synthesis 2016, 48, 751–760

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C. Wu et al.
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Synthesis
approximately 10:1. This result is consistent with our previ-
ous report on the Cu(I)-catalyzed Csp–Csp3 cross-coupling
of N-tosylhydrazones and trialkylsilylethynes.18,19
Next, the reaction scope was investigated for a variety of
aryldiazophosphonates under the optimized reaction con-
ditions (Scheme 3). The reactions examined under the
identical conditions afforded the corresponding allene
products in good yields. It is also noteworthy that the reac-
tions were not significantly affected by the substituents on
the aromatic ring in diazophosphonates 3b–i.
drazone 7a and phenylacetylene (4a) as the model sub-
strates. Following the reaction conditions applied in our
previous work,17 we first tried to use inorganic bases, such
as LiOt-Bu and K2CO3. Only a trace amount of the allene
product was observed when LiOt-Bu was used as the base,
while the yield reached 53% when K2CO3 was the base in the
reaction system. To our delight, the desired allene product
was obtained in 78% yield when i-Pr2NH was used as the
base. Moreover, ethyl and isopropyl groups could all be in-
troduced into the allene products in moderate to excellent
yields (Scheme 4).
(MeO)2OP
(MeO)2OP
Ph
CuI (20 mol%)
Ph
CuI (20 mol%)
i-Pr2NH (2.0 equiv)
N2
•
NNHTs
PO(OMe)2
7a–c
i-Pr2NH (1.0 equiv)
Ph
+
•
Ph
+
1,4-dioxane, 80 °C, 3 h
1,4-dioxane (1 mL)
80 °C, 3 h
R
R1
R1
PO(OMe)2
8a–c
R
3b–h
4a
6b–i
4a
Ph
Ph
Ph
(MeO)2OP
Ph
(MeO)2OP
Ph
(MeO)2OP
Ph
•
•
•
•
•
•
PO(OMe)2
8c, 58%
MeO
PO(OMe)2
8a,78%
PO(OMe)2
MeO
8b, 83%
Me
6b, 70%
6c, 95%
6d, 81%
Scheme 4 The scope of alkyldiazophosphonates. Reaction conditions:
N-tosylhydrazones 7a–c (1.2 equiv), 4a (0.2 mmol), CuI (20 mol%) and
i-Pr2NH (2.0 equiv) in 1,4-dioxane (1 mL) under N2 at 80 °C for 3 h; iso-
lated yields by column chromatography.
(MeO)2OP
Ph
Ph
(MeO)2OP
Ph
(MeO)2OP
•
•
•
Me
Ph
Cl
In conclusion, we have developed a novel synthetic
method for allenylphosphonates from terminal alkynes and
diazophosphonates through the alkynyl migratory inser-
tion into a Cu-carbene. The reaction is operationally simple
providing good yields, and the conditions are mild without
the need for complex ligands. It is thus expected that this
reaction will find wide applications in organic synthesis
and pharmaceutical research.
Me
6f, 82%
6e, 52%
(MeO)2OP
6g, 62%
Ph
(MeO)2OP
Ph
•
•
HOH2C
F
6h, 56%
6i, 68%
Scheme 3 The substrate scope of diazophosphonates. Reaction condi-
tions: diazophosphonates 3b–i (1.3 equiv), 4a (0.2 mmol), CuI (20
mol%), and i-Pr2NH (1 equiv) in 1,4-dioxane (1 mL) under N2 at 80 °C for
3 h; isolated yields by column chromatography.
All reactions were performed under an N2 atmosphere in a 10 mL
Schlenk tube. 1,4-Dioxane was dried over Na before use. For chro-
matographic purification, 200–300 mesh silica gel (Qingdao, China)
was employed. 1H NMR and 13C NMR spectra were recorded on Varian
300 MHz and Bruker ARX 400 MHz spectrometer in CDCl3 or DMSO-d6
solution and the chemical shifts were reported in parts per million
(δ) relative to internal standard TMS (0 ppm). Unless otherwise not-
ed, the chemicals obtained from commercial suppliers were used
without further purification.
Generally, diazophosphonates containing electron-do-
nating groups gave better results than those with electron-
withdrawing groups on the aromatic ring. In addition, di-
azophosphonate 3h with a free hydroxyl group is also sub-
jected to the reaction, affording the desired product 6h in
moderate yield.
CuI-Catalyzed Cross-Coupling of Diazophosphonates 3 with Ter-
minal Alkynes 4; General Procedure
Encouraged by the success in the reaction of aryldiazo-
phosphonates, we next tried to extend the reaction scope to
achieve the preparation of alkyldiazophosphonates. N-To-
sylhydrazones 7a-c derived from acylphosphonates were
used as the starting materials; these generated the corre-
sponding diazo compounds in situ in the presence of a base.
At the beginning of our study, we employed the N-tosylhy-
Under an N2 atmosphere, the corresponding terminal alkyne 4 (0.2
mmol) was added to a mixture of CuI (8 mg, 0.04 mmol), i-Pr2NH (20
mg, 0.2 mmol), and the appropriate diazophosphonate 3 (0.26 mmol)
in 1,4-dioxane (1 mL). The solution was stirred at 80 °C for 3 h and the
progress of the reaction was monitored by TLC. Upon completion of
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754
C. Wu et al.
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Synthesis
the reaction, the reaction mixture was cooled down to r.t. and filtered
through a short pad of silica gel using EtOAc as eluent. The solvent
was removed in vacuo to leave a crude mixture, which was purified
by column chromatography on silica gel to afford the corresponding
product 5 or 6.
materials. The crude residue was purified by column chromatography
(silica gel, EtOAc–PE, 1:1) to afford the respective final product 3;
yield: 50–90%.
α-Ketoalkylphosphonate N-Tosylhydrazones 7a–c;21 General Pro-
cedure (Scheme7 )
CuI-Catalyzed Cross-Coupling of α-Ketoalkylphosphonate N-To-
sylhydrazones 7 with Phenyl Acetylene (4a); General Procedure
O
NNHTs
P(OMe)2
O
P(OMe)3
0 °C–r.t.
TsNHNH2
Under an N2 atmosphere, phenyl acetylene (4a; 0.2 mmol) was added
to a mixture of CuI (8 mg, 0.04 mmol), i-Pr2NH (40 mg, 0.4 mmol),
and the appropriate α-ketoalkylphosphonate N-tosylhydrazone 7
(0.24 mmol) in 1,4-dioxane (1 mL). The solution was stirred at 80 °C
for 3 h and the progress of the reaction was monitored by TLC. Upon
completion of the reaction, the reaction mixture was cooled down to
r.t. and filtered through a short pad of silica gel using EtOAc as eluent.
The solvent was removed in vacuo to leave a crude mixture, which
was purified by column chromatography on silica gel to afford the
corresponding product 8.
R
R
P(OMe)2
THF, HCl
0 °C–r.t.
R
Cl
O
O
7a–c
Scheme 7
Dimethylα-Ketoalky1phosphonates: Under an N2 atmosphere, the ap-
propriate acyl halide (20 mmol) was stirred in a flask equipped with a
dropping funnel and a magnetic stirring assembly at 0 °C. P(OMe)3
(2.6 g, 21 mmol, distilled before use) was added dropwise over a peri-
od of 20–60 min, depending on the reaction scale. The reaction mix-
ture was stirred for 6 h at r.t. and the solution was used directly in the
following step without further workup.
Dimethyl (1-Diazo-2-oxopropyl)phosphonate (Scheme 5)
O
O
O
O
NaH (1.1 equiv)
α-Ketoalkylphosphonate N-Tosylhydrazones: Under an ambient atmo-
sphere, a solution of pure TsNHNH2 (3.72 g, 20 mmol) in THF (20 mL)
in a 50 mL flask was cooled to 0 °C and concd HCl (1.8 mL) was added.
The resulting solution was stirred in an ice bath while the above-
mentioned mixture solution was added over a 5 min period. The mix-
ture was stirred at r.t. for 6 h. The resulting white precipitate was fil-
tered and dried to give the final product 7; yield: 70–80%.
p-ABSA
P(OMe)2
P(OMe)2
r.t.
toluene, THF
0 °C, 1 h
N2
Scheme 5
Under an N2 atmosphere, a suspension of NaH (60% in oil, 0.88 g, 22.0
mmol) in toluene (85 mL) and THF (18 mL) was stirred and cooled to
0 °C in an ice–water bath for 30 min. To this suspension was added
slowly dimethyl 2-oxopropylphosphonate (3.32 g, 20.0 mmol). The
mixture was stirred at 0 °C for 1 h, and p-acetamidobenzenesulfonyl
azide (p-ABSA; 5.28 g, 22.0 mmol) was then added. The reaction was
warmed to r.t. and stirring was continued overnight. The mixture was
filtered through a Celite pad, and the filtrate was evaporated in vacuo
to remove the volatile materials. The crude residue was purified by
chromatography (silica gel, PE–EtOAc, 1:1) to give the product as a
yellow oil; yield: 2.38 g (62%).
Dimethyl [Diazo(phenyl)methyl]phosphonate (3a)20a
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 360 mg
(80%); yellow oil; Rf = 0.45 (EtOAc–PE, 1:1).
1H NMR (400 MHz, CDCl3): δ = 7.34–7.38 (m, 2 H), 7.13–7.17 (m, 3 H),
3.81 (d, J = 11.9 Hz, 6 H).
Dimethyl [Diazo(3-methoxyphenyl)methyl]phosphonate (3b)20a
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 297 mg
(58%); yellow oil; Rf = 0.45 (EtOAc–PE, 1:1).
1H NMR (400 MHz, CDCl3): δ = 7.27 (t, J = 7.9 Hz, 1 H), 6.75 (d, J = 8.2
Hz, 1 H), 6.68–6.71 (m, 2 H), 3.81 (d, J = 11.9 Hz, 6 H), 3.80 (s, 3 H).
Aryldiazophosphonates 3a–i20 (Scheme 6)
O
O
P(OMe)2
N2
Pd(PPh3)4 (5 mol%)
K2CO3
N2
+
P(OMe)2
O
Dimethyl [Diazo(4-methoxyphenyl)methyl]phosphonate (3c)20a
R
toluene–MeOH (1:1), r.t.
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 297 mg
(58%); yellow oil; Rf = 0.45 (EtOAc–PE, 1:1).
I
3a–i
R
1H NMR (400 MHz, CDCl3): δ = 7.09–7.12 (m, 2 H), 6.92–6.94 (m, 2 H),
3.81 (d, J = 12.0 Hz, 6 H), 3.80 (s, 3 H).
Scheme 6
Under an ambient atmosphere, Pd(PPh3)4 (116 mg, 5 mol%), K2CO3
(552 mg, 4.0 mmol), and the corresponding aryl iodide (2.0 mmol)
were suspended in MeOH (5 mL) and toluene (5 mL) in a 25 mL flask.
Dimethyl (1-diazo-2-oxopropyl)phosphonate (499 mg, 1.3 equiv) was
then added, and the resulting solution was stirred at r.t. for 5 h. The
mixture was filtered through a short pad of silica gel eluting with
EtOAc and the filtrate was evaporated in vacuo to remove the volatile
Dimethyl [Diazo(p-tolyl)methyl]phosphonate (3d)20a
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 346 mg
(72%); yellow oil; Rf = 0.45 (EtOAc–PE, 1:1).
1H NMR (400 MHz, CDCl3): δ = 7.17 (d, J = 8.4 Hz, 2 H), 7.06 (d, J = 8.4
Hz, 2 H), 3.80 (d, J = 11.6 Hz, 6 H), 2.33 (s, 3 H).
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Dimethyl [(4-Chlorophenyl)(diazo)methyl]phosphonate (3e)20b
HRMS (ESI): m/z [(M + H)+] calcd for C17H18O3P: 301.0988; found:
301.0991.
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 365 mg
(70%); yellow oil; Rf = 0.45 (EtOAc–PE, 1:1).
Dimethyl [1-Phenyl-3-(p-tolyl)propa-1,2-dien-1-yl]phosphonate
(5b)
1H NMR (400 MHz, CDCl3): δ = 7.31–7.34 (m, 2 H), 7.08–7.11 (m, 2 H),
3.82 (d, J = 12.0 Hz, 6 H).
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 57 mg
(90%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1).
13C NMR (100 MHz, CDCl3): δ = 130.0, 128.5, 124.0 (d, J = 9.5 Hz),
122.8 (d, J = 5.5 Hz), 52.2 (d, J = 5.1 Hz).
IR (film): 2952, 1928, 1543, 1493, 1260, 1027, 830, 770 cm–1
.
Dimethyl [Diazo(3,4-dimethylphenyl)methyl]phosphonate (3f)20a
1H NMR (400 MHz, CDCl3): δ = 7.63 (d, J = 8.0 Hz, 2 H), 7.34 (t, J = 7.2
Hz, 2 H), 7.24–7.29 (m, 3 H), 7.15 (d, J = 8.0 Hz, 2 H), 6.74 (d, J = 12.4
Hz, 1 H), 3.80 (d, J = 11.2 Hz, 3 H), 3.77 (d, J = 10.8 Hz, 3 H), 2.34 (s, 3
H).
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 320 mg
(65%); yellow oil; Rf = 0.45 (EtOAc–PE, 1:1).
13C NMR (100 MHz, CDCl3): δ = 212.70 (d, J = 2.7 Hz), 138.05 (d, J = 1.7
Hz), 131.20 (d, J = 8.1 Hz), 129.64 (d, J = 1.0 Hz), 128.67, 128.21 (d, J =
7.8 Hz), 127.96, 127.53 (d, J = 6.1 Hz), 127.08 (d, J = 2.2 Hz), 100.52 (d,
J = 187.7 Hz), 97.80 (d, J = 15.3 Hz), 53.39 (d, J = 6.1 Hz), 53.29 (d, J =
6.4 Hz), 21.14.
EI-MS: m/z (%) = 314 (M+, 49), 299 (16), 282 (6), 267 (7), 221 (5), 205
(100), 189 (12).
1H NMR (400 MHz, CDCl3): δ = 7.12 (d, J = 8.5 Hz, 1 H), 6.92–6.90 (m, 2
H), 3.80 (d, J = 11.9 Hz, 6 H), 2.26 (s, 3 H), 2.24 (s, 3 H).
Dimethyl [(1,1′-Biphenyl)-4-yl(diazo)methyl]phosphonate (3g)20b
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 301 mg
(59%); yellow oil; Rf = 0.45 (EtOAc–PE, 1:1).
1H NMR (400 MHz, CDCl3): δ = 7.60 (d, J = 8.4 Hz, 2 H), 7.57 (d, J = 7.6
Hz, 2 H), 7.42–7.45 (m, 2 H), 7.32–7.36 (m, 1 H), 7.23 (d, J = 8.4 Hz, 2
H), 3.84 (d, J = 12.0 Hz, 6 H).
HRMS (ESI): m/z [(M + H)+] calcd for C18H20O3P: 315.1145; found:
315.1149.
Dimethyl [3-(4-Methoxyphenyl)-1-phenylpropa-1,2-dien-1-
yl]phosphonate (5c)
13C NMR (100 MHz, CDCl3): δ = 140.2, 138.1, 128.8, 127.9, 127.3,
126.7, 125.2 (d, J = 9.5 Hz), 122.9 (d, J = 5.5 Hz), 53.2 (d, J = 5.1 Hz).
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 65 mg
(98%); colorless oil; Rf = 0.40 (EtOAc–PE, 1:1).
Dimethyl {Diazo[4-(hydroxymethyl)phenyl]methyl}phosphonate
(3h)20b
IR (film): 2953, 1929, 1606, 1511, 1250, 1173, 1027, 831, 730 cm–1
.
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 48 mg
(45%); yellow oil; Rf = 0.40 (EtOAc–PE, 2:1).
1H NMR (400 MHz, CDCl3): δ = 7.37 (d, J = 8.4 Hz, 2 H), 7.15 (d, J = 8.0
Hz, 2 H), 4.67 (s, 2 H), 3.81 (d, J = 12.0 Hz, 6 H).
1H NMR (400 MHz, CDCl3): δ = 7.63 (d, J = 8.0 Hz, 2 H), 7.34 (d, J = 8.0
Hz, 2 H), 7.28 (d, J = 8.5 Hz, 3 H), 6.88 (d, J = 8.8 Hz, 2 H), 6.74 (d, J =
12.8 Hz, 1 H), 3.80 (d, J = 11.2 Hz, 3 H), 3.79 (s, 3 H), 3.78 (d, J = 11.2
Hz, 3 H).
13C NMR (100 MHz, CDCl3): δ = 212.71 (d, J = 2.7 Hz), 159.43, 131.34
(d, J = 8.3 Hz), 128.67, 128.41 (d, J = 2.4 Hz), 127.94, 127.52 (d, J = 6.0
Hz), 123.28 (d, J = 8.1 Hz), 114.45, 100.52 (d, J = 188.0 Hz), 97.60 (d, J =
15.3 Hz), 55.21, 53.37 (d, J = 6.1 Hz), 53.48 (d, J = 6.5 Hz).
EI-MS: m/z (%) = 330 (M+, 39), 315 (25), 283 (7), 221 (100), 206 (10),
178 (20), 152 (8), 109 (5).
13C NMR (100 MHz, CDCl3): δ = 138.4, 128.0, 125.2 (d, J = 9.5 Hz),
122.6 (d, J = 4.4 Hz), 64.5, 53.1 (d, J = 4.9 Hz).
Dimethyl [Diazo(4-fluorophenyl)methyl]phosphonate (3i)20a
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 365 mg
(70%); yellow oil; Rf = 0.45 (EtOAc–PE, 1:1).
HRMS (ESI): m/z [(M + H)+] calcd for C18H20O4P: 331.1094; found:
331.1099.
1H NMR (400 MHz, CDCl3): δ = 7.12–7.16 (m, 2 H), 7.05–7.09 (m, 2 H),
3.82 (d, J = 11.9 Hz, 6 H).
Dimethyl {3-[4-(Dimethylamino)phenyl]-1-phenylpropa-1,2-dien-
1-yl}phosphonate (5d)
Dimethyl (1,3-Diphenylpropa-1,2-dien-1-yl)phosphonate (5a)
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 39 mg
(57%); colorless oil; Rf = 0.40 (EtOAc–PE, 1:1).
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 51 mg
(85%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1).
IR (film): 2987, 1924, 1607, 1523, 1250, 1028, 831, 730 cm–1
.
IR (film): 2952, 1930, 1598, 1493, 1251, 1208, 911, 831, 731 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.64 (d, J = 8.0 Hz, 2 H), 7.22–7.35 (m, 5
H), 6.73 (d, J = 12.8 Hz, 1 H), 6.67–6.70 (m, 2 H), 3.80 (d, J = 11.2 Hz, 3
H), 3.78 (d, J = 11.6 Hz, 3 H), 2.96 (s, 6 H).
13C NMR (100 MHz, CDCl3): δ = 213.33 (d, J = 2.8 Hz), 150.28, 131.79
(d, J = 9.2 Hz), 128.63, 128.24 (d, J = 2.2 Hz), 127.76, 127.53 (d, J = 6.2
Hz), 118.03 (d, J = 7.9 Hz), 112.57, 100.21 (d, J = 188.6 Hz), 98.14 (d, J =
15.6 Hz), 53.43 (d, J = 6.2 Hz), 53.31 (d, J = 6.6 Hz), 42.29.
1H NMR (400 MHz, CDCl3: δ = 7.64 (d, J = 8.0 Hz, 2 H), 7.31–7.35 (m, 6
H), 7.25–7.27 (m, 2 H), 6.76 (d, J = 12.4 Hz, 1 H), 3.80 (d, J = 11.6 Hz, 3
H), 3.77 (d, J = 11.2 Hz, 3 H).
13C NMR (100 MHz, CDCl3): δ = 212.58 (d, J = 2.7 Hz), 131.24 (d, J = 8.0
Hz), 130.96 (d, J = 7.7 Hz), 128.86 (d, J = 1.2 Hz), 128.63, 127.98,
127.48 (d, J = 6.0 Hz), 127.11, 127.08, 100.60 (d, J = 187.2 Hz), 97.95
(d, J = 15.2 Hz), 53.30 (d, J = 6.6 Hz), 53.22 (d, J = 6.4 Hz).
EI-MS: m/z (%) = 343 (M+, 7), 235 (100), 199 (15), 165 (58), 105 (7), 79
(3).
EI-MS: m/z (%) = 300 (M+, 10), 281 (12), 263 (5), 249 (13), 239 (100),
207 (80), 191 (10), 155 (5), 117 (11), 105 (15), 91 (70).
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HRMS (ESI): m/z [(M + H)+] calcd for C19H23NO3P: 344.1410; found:
EI-MS: m/z (%) = 368 (M+, 50), 353 (8), 336 (7), 306 (5), 275 (5), 259
344.1413.
(100), 240 (25), 169 (28), 109 (21).
HRMS (ESI): m/z [(M + H)+] calcd for C18H17F3O3P: 369.0862; found:
369.0869.
Dimethyl [3-(4-Chlorophenyl)-1-phenylpropa-1,2-dien-1-yl]phos-
phonate (5e)
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 58 mg
(86%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1).
Dimethyl [3-(2-Chlorophenyl)-1-phenylpropa-1,2-dien-1-yl]phos-
phonate (5h)
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 52 mg
(78%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1).
IR (film): 1930, 1491, 1257, 1027, 831, 760 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.61 (d, J = 8.0 Hz, 2 H), 7.27–7.38 (m, 7
H), 6.73 (d, J = 12.8 Hz, 1 H), 3.81 (d, J = 11.2 Hz, 3 H), 3.78 (d, J = 10.8
Hz, 3 H).
13C NMR (100 MHz, CDCl3): δ = 212.66 (d, J = 2.7 Hz), 133.77 (d, J = 2.0
Hz), 130.75 (d, J = 7.6 Hz), 129.95 (d, J = 8.1 Hz), 129.16 (d, J = 1.1 Hz),
128.79, 128.35 (d, J = 2.3 Hz), 128.23, 127.59 (d, J = 5.9 Hz), 101.19 (d,
J = 186.9 Hz), 97.16 (d, J = 15.3 Hz), 53.42 (d, J = 6.7 Hz), 53.35 (d, J =
6.9 Hz).
IR (film): 2954, 1932, 1738, 1477, 1247, 1030, 909, 833, 730 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.63 (d, J = 8.0 Hz, 2 H), 7.46–7.49 (m, 1
H), 7.34–7.41 (m, 3 H), 7.28–7.32 (m, 1 H), 7.17–7.25 (m, 3 H), 3.83 (d,
J = 11.6 Hz, 3 H), 3.79 (d, J = 11.2 Hz, 3 H).
13C NMR (100 MHz, CDCl3): δ = 213.04 (d, J = 2.7 Hz), 132.36 (d, J = 3.0
Hz), 130.59 (d, J = 7.4 Hz), 129.88, 129.40 (d, J = 7.9 Hz), 129.00 (d, J =
1.2 Hz), 128.68, 128.50 (d, J = 2.2 Hz), 128.09, 127.53 (d, J = 6.2 Hz),
127.07, 100.79 (d, J = 186.8 Hz), 94.36 (d, J = 15.2 Hz), 53.30 (d, J = 6.1
Hz).
EI-MS: m/z (%) = 334 (M+, 42), 319 (11), 299 (9), 287 (5), 269 (5), 237
(7), 225 (100), 189 (48), 163 (8), 109 (10).
HRMS (ESI): m/z [(M + H)+] calcd for C17H17ClO3P: 335.0598; found:
EI-MS: m/z (%) = 334 (M+, 62), 319 (12), 299 (25), 225 (100), 189 (60),
335.0605.
163 (5), 109 (7).
HRMS (ESI): m/z [(M + H)+] calcd for C17H17ClO3P: 335.0598; found:
335.0606.
Dimethyl [3-(4-Bromophenyl)-1-phenylpropa-1,2-dien-1-yl]phos-
phonate (5f)
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 61 mg
(80%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1).
Dimethyl [3-(6-Methoxynaphthalen-2-yl)-1-phenylpropa-1,2-
dien-1-yl]phosphonate (5i)
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 72 mg
(95%); colorless oil; Rf = 0.45 (EtOAc–PE, 1:1).
IR (film): 1930, 1487, 1256, 1027, 831, 762 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.61 (d, J = 8.0 Hz, 2 H), 7.47 (d, J = 8.0
Hz, 2 H), 7.30–7.38 (m, 3 H), 7.21–7.23 (m, 2 H), 6.71 (d, J = 12.2 Hz, 1
H), 3.80 (d, J = 11.6 Hz, 3 H), 3.78 (d, J = 11.2 Hz, 3 H).
IR (film): 2952, 2242, 1929, 1732, 1629, 1604, 1235, 1030, 908, 730
cm–1
.
13C NMR (100 MHz, CDCl3): δ = 212.66 (d, J = 2.7 Hz), 132.14 (d, J = 1.1
Hz), 130.71 (d, J = 7.3 Hz), 130.46 (d, J = 8.1 Hz), 128.82, 128.67 (d, J =
2.5 Hz), 128.28, 127.62 (d, J = 6.0 Hz), 121.91 (d, J = 2.0 Hz), 101.28 (d,
J = 186.9 Hz), 97.26 (d, J = 15.3 Hz), 53.46 (d, J = 6.3 Hz), 53.39 (d, J =
6.6 Hz).
EI-MS: m/z (%) = 378 (M+, 32), 363 (5), 299 (33), 269 (100), 237 (21),
189 (85), 163 (7), 109 (11).
1H NMR (400 MHz, CDCl3): δ = 7.67–7.70 (m, 5 H), 7.45–7.47 (m, 1 H),
7.37 (t, J = 8.0 Hz, 2 H), 7.26–7.309 (m, 1 H), 7.10–7.15 (m, 2 H), 6.81
(d, J = 12.4 Hz, 1 H), 3.89 (s, 3 H), 3.82 (d, J = 11.2 Hz, 3 H), 3.79 (d, J =
11.2 Hz, 3 H).
13C NMR (100 MHz, CDCl3): δ = 213.07 (d, J = 2.5 Hz), 157.95, 134.23,
131.20 (d, J = 8.2 Hz), 129.24, 128.92 (d, J = 1.3 Hz), 128.72, 128.03,
127.58 (d, J = 5.9 Hz), 127.27, 126.40 (d, J = 3.0 Hz), 126.32 (d, J = 8.2
Hz), 124.96 (d, J = 1.2 Hz), 119.20, 105.80, 100.79 (d, J = 187.7 Hz),
98.45 (d, J = 15.3 Hz), 55.18, 53.45 (d, J = 6.3 Hz), 53.32 (d, J = 6.5 Hz).
HRMS (ESI): m/z [(M + H)+] calcd for C17H17BrO3P: 379.0093; found:
379.0101.
HRMS (ESI): m/z [(M + H)+] calcd for C22H22O4P: 381.1250; found:
381.1258.
Dimethyl {1-Phenyl-3-[4-(trifluoromethyl)phenyl]propa-1,2-
dien-1-yl}phosphonate (5g)
Dimethyl (1-Phenyl-3-(thiophen-3-yl)propa-1,2-dien-1-yl]phos-
phonate (5j)
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 52 mg
(70%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1).
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 34 mg
(56%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1).
IR (film): 2959, 1931, 1616, 1324, 1259, 1166, 1123, 1064, 1027, 831,
762 cm–1
.
IR (film): 2952, 1929, 1492, 1254, 1027, 827, 770, 731 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.61 (t, J = 7.6 Hz, 4 H), 7.47 (d, J = 8.0
Hz, 2 H), 7.27–7.39 (m, 3 H), 6.79 (d, J = 12.8 Hz, 1 H), 3.83 (d, J = 10.8
Hz, 3 H), 3.80 (d, J = 10.8 Hz, 3 H).
13C NMR (100 MHz, CDCl3): δ = 212.97 (d, J = 2.6 Hz), 135.50 (d, J = 9.1
Hz), 130.46 (d, J = 7.2 Hz), 129.90 (q, J = 32.8 Hz), 128.88, 128.41,
127.66 (d, J = 3.0 Hz), 127.35 (d, J = 2.2 Hz), 125.95 (d, J = 3.1 Hz),
123.90 (q, J = 270.8 Hz), 101.52 (d, J = 186.5 Hz), 97.10 (d, J = 15.1 Hz),
53.47 (d, J = 6.0 Hz), 53.41 (d, J = 5.4 Hz).
1H NMR (400 MHz, CDCl3): δ = 7.52 (d, J = 8.0 Hz, 2 H), 7.21–7.39 (m, 5
H), 7.10–7.11 (m, 1 H), 6.84 (d, J = 12.8 Hz, 1 H), 3.81 (d, J = 11.2 Hz, 3
H), 3.80 (d, J = 11.2 Hz, 3 H).
13C NMR (100 MHz, CDCl3): δ = 213.33 (d, J = 2.7 Hz), 131.91 (d, J = 8.2
Hz), 131.20 (d, J = 8.1 Hz), 128.73, 128.05, 127.64 (d, J = 6.0 Hz),
126.72, 126.01 (d, J = 1.0 Hz), 122.87 (d, J = 3.6 Hz), 99.91 (d, J = 187.5
Hz), 92.59 (d, J = 15.3 Hz), 53.39 (d, J = 6.2 Hz), 53.33 (d, J = 6.7 Hz).
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EI-MS: m/z (%) = 306 (M+, 30), 291 (21), 274 (7), 259 (6), 207 (25), 197
(100), 152 (12), 91 (10).
HRMS (ESI): m/z [(M + H)+] calcd for C15H16O3PS: 307.0552; found:
307.0557.
13C NMR (100 MHz, CDCl3): δ = 209.67 (d, J = 4.5 Hz), 209.45 (d, J = 4.5
Hz), 131.32 (d, J = 4.7 Hz), 131.25 (d, J = 4.5 Hz), 128.63, 128.60,
127.81, 127.42 (d, J = 5.7 Hz), 127.36 (d, J = 5.6 Hz), 100.63 (d, J = 14.4
Hz), 100.49 (d, J = 14.4 Hz), 98.36 (d, J = 187.9 Hz), 97.85 (d, J = 187.3
Hz), 65.51 (d, J = 6.0 Hz), 64.98 (d, J = 6.0 Hz), 53.21 (d, J = 6.0 Hz),
53.18 (d, J = 5.9 Hz), 53.13 (d, J = 5.3 Hz), 53.08 (d, J = 5.6 Hz), 23.31 (d,
J = 2.7 Hz), 23.18 (d, J = 3.0 Hz).
Dimethyl [3-(Cyclohex-2-en-1-yl)-1-phenylpropa-1,2-dien-1-
yl]phosphonate (5k)
HRMS (ESI): m/z [(M + Na)+] calcd for C13H17O4PNa: 291.0757; found:
291.0752.
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 58 mg
(95%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1).
Dimethyl [1-Phenyl-3-(triisopropylsilyl)prop-2-yn-1-yl]phospho-
nate (5n′)
IR (film): 2928, 1922, 1493, 1443, 1259, 1026, 829, 765, 730 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.97 (d, J = 8.0 Hz, 2 H), 7.34 (t, J = 8.0
Hz, 2 H), 7.24–7.28 (m, 1 H), 6.43 (d, J = 12.4 Hz, 1 H), 5.48 (d, J = 2.4
Hz, 1 H), 3.80 (d, J = 11.2 Hz, 3 H), 3.78 (d, J = 11.2 Hz, 3 H), 2.14–2.19
(m, 4 H), 1.58–1.70 (m, 4 H).
13C NMR (100 MHz, CDCl3): δ = 212.50 (d, J = 2.9 Hz), 131.89 (d, J = 8.6
Hz), 129.55 (d, J = 8.6 Hz), 129.27 (d, J = 5.0 Hz), 128.54, 127.64,
127.34 (d, J = 5.8 Hz), 101.28 (d, J = 15.3 Hz), 99.56 (d, J = 189.2 Hz),
53.13 (d, J = 6.4 Hz), 53.11 (d, J = 6.1 Hz), 25.89 (d, J = 2.1 Hz), 25.88,
22.18, 21.94.
EI-MS: m/z (%) = 304 (M+, 30), 289 (5), 276 (4), 194 (100), 179 (19),
165 (30), 152 (8), 115 (18), 91 (11), 79 (7).
HRMS (ESI): m/z [(M + H)+] calcd for C17H22O3P: 305.1301; found:
305.1301.
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 52 mg
(68%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1). The two isomers were
difficult to separate; hence the spectral data for the main product are
given.
IR (film): 2944, 2865, 2174, 1918, 1463, 1263, 1030, 830, 679 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.51–7.54 (m, 2 H), 7.27–7.37 (m, 3 H),
4.20 (d, J = 28.4 Hz, 1 H), 3.72 (d, J = 5.2 Hz, 3 H), 3.69 (d, J = 5.2 Hz, 3
H), 1.11 (s, 21 H).
13C NMR (100 MHz, CDCl3): δ = 132.87 (d, J = 8.6 Hz), 128.87 (d, J = 5.1
Hz), 128.42 (d, J = 3.0 Hz), 127.58 (d, J = 3.5 Hz), 100.80 (d, J = 13.4 Hz),
86.67 (d, J = 8.5 Hz), 54.36 (d, J = 7.0 Hz), 53.82 (d, J = 6.9 Hz), 38.42 (d,
J = 137.2 Hz), 18.51, 11.21.
EI-MS: m/z (%) = 380 (M+, 5), 337 (100), 203 (5), 181 (3), 143 (5), 91
(70).
HRMS (ESI): m/z [(M + H)+] calcd for C20H34O3PSi: 381.2009; found:
381.2018.
Dimethyl (3-Cyclohexyl-1-phenylpropa-1,2-dien-1-yl)phospho-
nate (5l)
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 49 mg
(80%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1).
Dimethyl [1-(3-Methoxyphenyl)-3-phenylpropa-1,2-dien-1-
yl]phosphonate (6b)
IR (film): 2925, 2551, 1939, 1448, 1259, 1027, 828, 766 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.57 (d, J = 8.0 Hz, 2 H), 7.33 (t, J = 7.6
Hz, 2 H), 7.23–7.28 (m, 1 H), 5.75 (dd, J = 6.0, 12.4 Hz, 1 H), 3.78 (d, J =
11.2 Hz, 6 H), 2.22–2.27 (m, 1 H), 1.87–1.90 (m, 2 H), 1.74–1.77 (m, 2
H), 1.66 (d, J = 12.4 Hz, 1 H), 1.22–1.30 (m, 5 H).
13C NMR (100 MHz, CDCl3): δ = 209.97 (d, J = 4.3 Hz), 132.08 (d, J = 9.1
Hz), 128.52, 127.42, 127.19 (d, J = 6.0 Hz), 100.58 (d, J = 14.9 Hz), 97.1
(d, J = 190.2 Hz), 53.06 (d, J = 6.0 Hz), 53.03 (d, J = 5.9 Hz), 37.11 (d, J =
5.7 Hz), 32.88 (d, J = 3.0 Hz), 32.74 (d, J = 3.1 Hz), 25.85, 25.82, 25.79.
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 46 mg
(70%); colorless oil; Rf = 0.40 (EtOAc–PE, 1:1).
IR (film): 2954, 1925, 1957, 1485, 1258, 1179, 1027, 831, 752 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.32–7.38 (m, 4 H), 7.24–7.29 (m, 3 H),
7.13–7.22 (m, 2 H), 6.76 (d, J = 12.8 Hz, 1 H), 3.81 (d, J = 11.6 Hz, 3 H),
3.79 (s, 3 H), 3.78 (d, J = 11.2 Hz, 3 H).
13C NMR (100 MHz, CDCl3): δ = 212.83 (d, J = 2.9 Hz), 159.78, 132.47
(d, J = 7.8 Hz), 131.38 (d, J = 7.9 Hz), 129.74, 129.00 (d, J = 1.2 Hz),
128.12 (d, J = 1.2 Hz), 127.28 (d, J = 2.4 Hz), 120.16 (d, J = 5.9 Hz),
113.69, 113.27 (d, J = 6.4 Hz), 100.67 (d, J = 187.9 Hz), 98.09 (d, J = 15.3
Hz), 55.22, 53.49 (d, J = 6.9 Hz), 53.40 (d, J = 6.5 Hz).
EI-MS: m/z (%) = 306 (M+, 100), 277 (15), 265 (52), 237 (20), 224 (20),
196 (62), 167 (62), 153 (51), 129 (45), 115 (91), 93 (17).
HRMS (ESI): m/z [(M + H)+] calcd for C17H24O3P: 307.1458; found:
307.1461.
EI-MS: m/z (%) = 330 (M+, 53), 315 (11), 298 (7), 283 (8), 266 (7), 221
(100), 178 (21), 152 (10), 109 (7).
HRMS (ESI): m/z [(M + H)+] calcd for C18H20O4P: 331.1094; found:
31.1099.
Dimethyl (4-Hydroxy-1-phenylpenta-1,2-dien-1-yl)phosphonate
(5m)
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 37 mg
(62%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1). The diastereoisomers
were difficult to separate; hence the spectral data of the diastereoiso-
meric mixture are given below.
Dimethyl [1-(4-Methoxyphenyl)-3-phenylpropa-1,2-dien-1-
yl]phosphonate (6c)
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 63 mg
(95%); colorless oil; Rf = 0.40 (EtOAc–PE, 1:1).
IR (film): 3365, 2594, 1954, 1494, 1448, 1244, 1026, 831, 76 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.54 (t, J = 8.0 Hz, 2 H), 7.34 (t, J = 7.2
Hz, 2 H), 7.25–7.27 (m, 1 H), 5.87–5.96 (m, 1 H), 4.57–4.60 (m, 1 H),
3.79 (d, J = 11.2 Hz, 3 H), 3.76 (d, J = 11.2 Hz, 3 H), 1.42 (d, J = 6.4 Hz, 3
H).
IR (film): 2954, 1929, 1606, 1509, 1252, 1180, 1028, 834, 751 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.57 (d, J = 8.4 Hz, 2 H), 7.32–7.36 (m, 4
H), 7.25–7.28 (m, 1 H), 6.88 (d, J = 8.8 Hz, 2 H), 6.74 (d, J = 12.8 Hz, 1
H), 3.80 (d, J = 11.2 Hz, 3 H), 3.79 (s, 3 H), 3.78 (d, J = 11.6 Hz, 3 H).
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13C NMR (100 MHz, CDCl3): δ = 212.05 (d, J = 2.9 Hz), 159.49, 131.66
(d, J = 8.0 Hz), 128.93 (d, J = 2.2 Hz), 128.86 (d, J = 6.4 Hz), 127.97 (d, J
= 3.2 Hz), 127.17 (d, J = 2.2 Hz), 122.98 (d, J = 7.9 Hz), 114.20, 100.16
(d, J = 187.0 Hz), 98.05 (d, J = 15.3 Hz), 55.21, 53.40 (d, J = 6.1 Hz),
53.32 (d, J = 6.5 Hz).
13C NMR (100 MHz, CDCl3): δ = 212.41 (d, J = 3.0 Hz), 137.05, 136.83,
131.69 (d, J = 8.0 Hz), 130.02, 128.94 (d, J = 1.0 Hz), 128.64 (d, J = 6.3
Hz), 128.32 (d, J = 7.7 Hz), 127.95 (d, J = 1.7 Hz), 127.23 (d, J = 2.3 Hz),
125.08 (d, J = 5.9 Hz), 100.58 (d, J = 186.6 Hz), 97.84 (d, J = 15.3 Hz),
53.43 (d, J = 6.1 Hz), 53.33 (d, J = 6.4 Hz), 19.79, 19.45.
EI-MS: m/z (%) = 330 (M+, 51), 315 (10), 283 (7), 221 (100), 206 (5),
EI-MS: m/z (%) = 328 (M+, 50), 313 (4), 286 (7), 281 (4), 264 (4), 219
178 (12), 152 (5).
(100), 202 (15), 178 (7), 109 (5).
HRMS (ESI): m/z [(M + H)+] calcd for C18H20O4P: 331.1094; found:
HRMS (ESI): m/z [(M + H)+] calcd for C19H22O3P: 329.1301; found:
331.1099.
329.1307.
Dimethyl [3-Phenyl-1-(p-tolyl)propa-1,2-dien-1-yl]phosphonate
Dimethyl {1-[(1,1′-Biphenyl)-4-yl]-3-phenylpropa-1,2-dien-1-
(6d)
yl}phosphonate (6g)
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 51 mg
(81%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1).
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 54 mg
(62%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1).
IR (film): 2952, 1929, 1510, 1457, 1252, 1027, 830, 732 cm–1
.
IR (film): 2952, 1929, 1487, 1457, 1259, 1027, 832, 767, 695 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.52 (d, J = 8.0 Hz, 2 H), 7.31–7.36 (m, 4
H), 7.24–7.28 (m, 1 H), 7.15 (d, J = 8.4 Hz, 2 H), 6.74 (d, J = 12.4 Hz, 1
H), 3.80 (d, J = 11.2 Hz, 3 H), 3.77 (d, J = 11.2 Hz, 3 H), 2.34 (s, 3 H).
1H NMR (400 MHz, CDCl3): δ = 7.71 (d, J = 8.4 Hz, 2 H), 7.54–7.59 (m, 4
H), 7.41–7.45 (m, 2 H), 7.32–7.39 (m, 5 H), 7.25–7.29 (m, 1 H), 6.80 (d,
J = 12.4 Hz, 1 H), 3.84 (d, J = 11.2 Hz, 3 H), 3.81 (d, J = 11.6 Hz, 3 H).
13C NMR (100 MHz, CDCl3): δ = 212.41 (d, J = 2.7 Hz), 138.04, 131.54
(d, J = 8.0 Hz), 129.45, 128.92, 127.98 (d, J = 1.6 Hz), 127.96 (d, J = 6.7
Hz), 127.47 (d, J = 6.0 Hz), 127.19 (d, J = 2.3 Hz), 100.51 (d, J = 186.8
Hz), 97.98 (d, J = 15.3 Hz), 53.39 (d, J = 6.1 Hz), 53.31 (d, J = 6.3 Hz),
21.09.
13C NMR (100 MHz, CDCl3): δ = 212.89 (d, J = 2.6 Hz), 140.96, 140.40,
131.41 (d, J = 8.0 Hz), 130.01 (d, J = 7.9 Hz), 129.04, 128.78, 128.17 (d,
J = 1.2 Hz), 128.05 (d, J = 6.0 Hz), 127.49, 127.48 (d, J = 2.1 Hz), 127.31
(d, J = 2.3 Hz), 126.98, 100.53 (d, J = 187.4 Hz), 98.29 (d, J = 15.1 Hz),
53.53 (d, J = 6.1 Hz), 53.44 (d, J = 6.5 Hz).
EI-MS: m/z (%) = 314 (M+, 52), 299 (11), 282 (9), 267 (7), 250 (5), 205
EI-MS: m/z (%) = 376 (M+, 5), 357 (25), 330 (7), 281 (8), 221 (12), 207
(100), 169 (12).
(30), 133 (100), 105 (20), 77 (18).
HRMS (ESI): m/z [(M + H)+] calcd for C18H20O3P: 315.1145; found:
HRMS (ESI): m/z [(M + H)+] calcd for C23H22O3P: 377.1301; found:
315.1150.
377.1308.
Dimethyl [1-(4-Chlorophenyl)-3-phenylpropa-1,2-dien-1-yl]phos-
phonate (6e)
Dimethyl {1-[4-(Hydroxymethyl)phenyl]-3-phenylpropa-1,2-dien-
1-yl}phosphonate (6h)
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 35 mg
(52%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1).
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 43 mg
(56%); colorless oil; Rf = 0.30 (EtOAc–PE, 1:1).
IR (film): 2953, 1930, 1490, 1257, 1027, 835, 773 cm–1
.
IR (film): 3401, 2958, 1929, 1716, 1457, 1247, 1028, 833, 730 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.57 (d, J = 8.4 Hz, 2 H), 7.30–7.36 (m, 7
H), 6.78 (d, J = 12.8 Hz, 1 H), 3.81 (d, J = 11.6 Hz, 3 H), 3.78 (d, J = 11.6
Hz, 3 H).
1H NMR (400 MHz, CDCl3): δ = 7.52 (d, J = 8.4 Hz, 2 H), 7.31–7.39 (m, 1
H), 7.25–7.27 (m, 5 H), 7.19–7.22 (m, 1 H), 6.68 (d, J = 12.8 Hz, 1 H),
4.58 (s, 2 H), 3.72 (d, J = 11.2 Hz, 3 H), 3.69 (d, J = 10.8 Hz, 3 H).
13C NMR (100 MHz, CDCl3): δ = 212.67 (d, J = 2.7 Hz), 134.06, 131.05
(d, J = 7.6 Hz), 129.63 (d, J = 8.3 Hz), 129.05 (d, J = 1.0 Hz), 128.93,
128.75 (d, J = 5.9 Hz), 128.28 (d, J = 1.3 Hz), 127.28 (d, J = 2.4 Hz),
99.97 (d, J = 188.3 Hz), 98.46 (d, J = 5.0 Hz), 53.53 (d, J = 6.3 Hz), 53.44
(d, J = 6.6 Hz).
13C NMR (100 MHz, CDCl3): δ = 212.70 (d, J = 2.8 Hz), 141.26, 132.02
(d, J = 10.0 Hz), 131.37 (d, J = 8.0 Hz), 130.13 (d, J = 8.0 Hz), 129.01 (d,
J = 1.1 Hz), 128.14 (d, J = 1.1 Hz), 127.72 (d, J = 6.0 Hz), 127.26, 100.45
(d, J = 187.8 Hz), 98.15 (d, J = 15.3 Hz), 64.60, 53.50 (d, J = 6.8 Hz),
53.28 (d, J = 6.9 Hz).
EI-MS: m/z (%) = 334 (M+, 55), 319 (12), 302 (6), 287 (5), 225 (100),
HRMS (ESI): m/z [(M + H)+] calcd for C18H20O4P: 331.1094; found:
189 (50), 163 (5), 109 (10).
331.1099.
HRMS (ESI): m/z [(M + H)+] calcd for C17H17ClO3P: 335.0598; found:
335.0606.
Dimethyl [1-(4-Fluorophenyl)-3-phenylpropa-1,2-dien-1-yl]phos-
phonate (6i)
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 43 mg
(68%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1).
Dimethyl [1-(3,4-Dimethylphenyl)-3-phenylpropa-1,2-dien-1-
yl]phosphonate (6f)
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 54 mg
(82%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1).
IR (film): 2924, 1930, 1508, 1458, 1258, 1027, 840 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.59–7.63 (m, 2 H), 7.35 (d, J = 4.4 Hz, 4
H), 7.27–7.31 (m, 1 H), 7.04 (t, J = 8.4 Hz, 2 H), 6.77 (d, J = 12.4 Hz, 1
H), 3.82 (d, J = 11.6 Hz, 3 H), 3.78 (d, J = 11.6 Hz, 3 H).
IR (film): 2951, 1925, 1501, 1456, 1258, 1026, 831, 762 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.31–7.39 (m, 6 H), 7.24–7.28 (m, 1 H),
7.11 (d, J = 8.4 Hz, 1 H), 6.73 (d, J = 12.8 Hz, 1 H), 3.80 (d, J = 11.2 Hz, 3
H), 3.78 (d, J = 10.8 Hz, 3 H), 2.24 (s, 6 H).
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13C NMR (100 MHz, CDCl3): δ = 212.47 (d, J = 2.9 Hz), 162.58 (d, J =
247.0 Hz), 131.27 (d, J = 7.9 Hz), 129.50 (d, J = 6.0 Hz), 129.41 (d, J =
6.2 Hz), 129.07 (d, J = 0.9 Hz), 128.25 (d, J = 1.5 Hz), 127.28 (d, J = 2.3
Hz), 115.39 (d, J = 21.7 Hz), 99.94 (d, J = 188.2 Hz), 98.31 (d, J = 15.2
Hz), 53.55 (d, J = 6.1 Hz), 53.45 (d, J = 6.4 Hz).
EI-MS: m/z (%) = 318 (M+, 55), 303 (7), 286 (5), 271 (5), 254 (3), 225
(5), 209 (100), 163 (7), 109 (5).
Dimethyl (1-Phenylpenta-1,2-dien-3-yl)phosphonate (8b)
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel (EtOAc–PE, 1:1);
yield: 42 mg (83%); colorless oil; Rf = 0.5.
IR (film): 2952, 1938, 1458, 1250, 1025, 829, 775 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.14–7.27 (m, 5 H), 6.39 (td, J = 13.2,
3.2 Hz, 1 H), 3.69 (d, J = 11.2 Hz, 3 H), 3.66 (d, J = 11.6 Hz, 3 H), 2.20–
2.35 (m, 2 H), 1.81 (t, J = 7.2 Hz, 3 H).
13C NMR (100 MHz, CDCl3): δ = 209.13 (d, J = 4.9 Hz), 132.43 (d, J = 8.4
Hz), 128.77 (d, J = 1.3 Hz), 127.62 (d, J = 1.9 Hz), 126.87 (d, J = 2.6 Hz),
99.21 (d, J = 185.7 Hz), 97.30 (d, J = 16.3 Hz), 53.09 (d, J = 5.7 Hz),
53.03 (d, J = 5.9 Hz), 22.31 (d, J = 6.4 Hz), 12.57 (d, J = 7.8 Hz).
EI-MS: m/z (%) = 252 (M+, 30), 237 (30), 219 (5), 205 (11), 175 (5), 142
(100), 128 (79), 115 (60), 102 (11), 93 (10), 77 (9).
HRMS (ESI): m/z [(M + H)+] calcd for C13H18O3P: 253.0988; found:
253.0988.
HRMS (ESI): m/z [(M + H)+] calcd for C17H17FO3P: 319.0894; found:
319.6900.
Dimethyl [1-(2-Tosylhydrazono)ethyl]phosphonate (7a)21
Following the general procedure described above, the crude residue
was purified by recrystallization; yield: 5.12 g (80%); white solid; Rf =
0.30 (EtOAc–PE, 3:1). The E/Z-isomers were difficult to separate.
1H NMR (400 MHz, CDCl3): δ (E/Z-mixture) = 8.72 (s, 1 H), 7.82 (d, J =
8.4 Hz, 2 H), 7.32 (d, J = 8.0 Hz, 2 H), 3.72–3.75 (m, 6 H), 2.43 (s, 3 H),
2.02 (d, J = 9.6 Hz, 0.4 H), 1.95 (d, J = 10.8 Hz, 2.6 H).
Dimethyl (4-Methyl-1-phenylpenta-1,2-dien-3-yl)phosphonate
(8c)
Dimethyl [1-(2-Tosylhydrazono)propyl]phosphonate (7b)20b
Following the general procedure described above, the crude residue
was purified by recrystallization; yield: 4.68 g (70%); white solid; Rf =
0.30 (EtOAc–PE, 3:1).The E/Z-isomers were difficult to separate.
1H NMR (400 MHz, DMSO-d6): δ (E/Z-mixture) = 11.46 (s, 1 H), 7.73
(d, J = 8.4 Hz, 2 H), 7.43 (d, J = 8.0 Hz, 2 H), 3.53 (d, J = 10.8 Hz, 6 H),
2.34–2.43 (m, 5 H), 0.97 (t, J = 7.6 Hz, 3 H).
13C NMR (100 MHz, DMSO-d6): δ (E/Z-mixture) = 151.7 (d, J = 212 Hz),
143.8, 135.6, 129.6, 127.3, 53.2 (d, J = 6.5 Hz), 21.3 (d, J = 20.3 Hz),
21.0, 9.3.
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel (EtOAc–PE, 1:1);
yield: 31 mg (58%); colorless oil; Rf = 0.55.
IR (film): 2963, 1935, 1458, 1250, 1028, 830, 695 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.16–7.27 (m, 5 H), 6.40 (dd, J = 13.2,
2.0 Hz, 1 H), 3.68 (d, J = 10.8 Hz, 3 H), 3.65 (d, J = 11.2 Hz, 3 H), 2.55–
2.65 (m, 1 H), 1.14 (d, J = 6.8 Hz, 3 H), 1.11 (d, J = 6.8 Hz, 3 H).
13C NMR (100 MHz, CDCl3): δ = 208.69 (d, J = 4.8 Hz), 132.44 (d, J = 8.4
Hz), 128.82 (d, J = 1.3 Hz), 127.63 (d, J = 1.4 Hz), 136.77 (d, J = 2.5 Hz),
104.30 (d, J = 183.6 Hz), 97.80 (d, J = 16.3 Hz), 53.06 (d, J = 6.2 Hz),
53.00 (d, J = 6.4 Hz), 29.39 (d, J = 6.9 Hz), 22.89 (d, J = 5.8 Hz), 22.50 (d,
J = 5.3 Hz).
EI-MS: m/z (%) = 266 (M+, 92), 251 (75), 224 (91), 209 (15), 189 (14),
156 (95), 141 (89), 128 (53), 115 (100), 102 (15), 91 (17), 79 (16).
HRMS (ESI): m/z [(M + H)+] calcd for C14H20O3P: 267.1145; found:
267.1144.
Dimethyl (2-Methyl-1-(2-tosylhydrazono)propyl)phosphonate
(7c)21
Following the general procedure above, the crude residue was puri-
fied by recrystallization; yield: 5.15 g (74%); white solid; Rf = 0.30
(EtOAc–PE, 3:1). The E/Z-isomers were difficult to separate.
1H NMR (400 MHz, DMSO-d6): δ (E/Z-mixture) = 11.48 (s, 1 H), 7.73
(d, J = 8.0 Hz, 2 H), 7.43 (d, J = 8.0 Hz, 2 H), 3.50 (d, J = 11.2 Hz, 6 H),
3.00–3.14 (m, 1 H), 2.38 (s, 3 H), 1.05 (d, J = 6.8 Hz, 3 H).
Acknowledgment
Dimethyl (4-Phenylbuta-2,3-dien-2-yl)phosphonate (8a)
Following the general procedure described above, the crude residue
was purified by column chromatography on silica gel; yield: 37 mg
(78%); colorless oil; Rf = 0.50 (EtOAc–PE, 1:1).
The project was supported by National Basic Research Program (973
Program, No. 2012CB821600) and Natural Science Foundation of Chi-
na (Grant 21272010 and 21332002).
IR (film): 2953, 1943, 1460, 1256, 1024, 831, 780 cm–1
.
1H NMR (400 MHz, CDCl3): δ = 7.13–7.25 (m, 5 H), 6.29 (qd, J = 13.2,
2.8 Hz, 1 H), 3.68 (d, J = 11.2 Hz, 3 H), 3.66 (d, J = 11.6 Hz, 3 H), 1.81
(dd, J = 14.0, 3.0 Hz, 3 H).
13C NMR (100 MHz, CDCl3): δ = 209.75 (d, J = 2.8 Hz), 132.13 (d, J = 8.2
Hz), 128.64 (d, J = 1.3 Hz), 127.51 (d, J = 1.4 Hz), 126.94 (d, J = 2.5 Hz),
95.34 (d, J = 16.2 Hz), 92.15 (d, J = 187.6 Hz), 52.98 (d, J = 5.4 Hz),
52.92 (d, J = 6.0 Hz), 14.90 (d, J = 5.7 Hz).
EI-MS: m/z (%) = 238 (M+, 28), 223 (7), 205 (5), 191 (2), 145 (2), 128
(100), 109 (7), 102 (10), 93 (5), 77 (9).
HRMS (ESI): m/z [(M + H)+] calcd for C12H16O3P: 239.0832; found:
239.0832.
Supporting Information
Supporting information for this article is available online at
http://dx.doi.org/10.1055/s-0035-1561298.
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References
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© Georg Thieme Verlag Stuttgart · New York — Synthesis 2016, 48, 751–760