Synthesis of Vinylcyclopropane-Fused Pyrazolone Derivatives by Sulfur Ylide-Initiated 1,6-Michael Addition-Cyclization Reactions

Article abstract of DOI:10.1002/ejoc.201800710

A highly diastereoselective cyclopropanation of α,β,γ,δ-unsaturated pyrazolones has been disclosed. This method allows for construction of a vinylcyclopropane-fused pyrazolone framework via a 1,6-addition/substitution sequence providing excellent regio- and chemoselectivity, good yields, broad functional group tolerance and gram-scale capacity. Moreover, the subsequent transformation of derivatives demonstrates great potential in building useful synthetic architectures.

Full text of DOI:10.1002/ejoc.201800710

A Journal of
Accepted Article
Title: Synthesis of vinylcyclopropane-fused pyrazolone derivatives via
sulfur ylide-initiated 1,6-Michael addition-cyclization reaction
Authors: Xiang Li, Yan-Qing Liu, Jing-Wen Kang, Fei-Yu Chen, Xi-Guo
He, Shan-Shan Yuan, Li Guo, Cheng Peng, and Wei Huang
This manuscript has been accepted after peer review and appears as an
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of the final Version of Record (VoR). This work is currently citable by
using the Digital Object Identifier (DOI) given below. The VoR will be
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the VoR from the journal website shown below when it is published
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To be cited as: Eur. J. Org. Chem. 10.1002/ejoc.201800710
Link to VoR: http://dx.doi.org/10.1002/ejoc.201800710
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European Journal of Organic Chemistry
10.1002/ejoc.201800710
FULL PAPER
Synthesis of Vinylcyclopropane-Fused Pyrazolone Derivatives via
Sulfur Ylide-Initiated 1,6-Michael Addition-Cyclization Reactions
Xiang Li,[a,c] Yan-Qing Liu,[b,c] Jing-Wen Kang, Fei-Yu Chen, Xi-Guo He, Shan-Shan Yuan, Li
[b]
[b]
[a]
[a]
[
b]
[a,b]
and Wei Huang*[a]
Guo, Cheng Peng*
Abstract: A highly diastereoselective cyclopropanation of α,β,γ,δ-
unsaturated pyrazolones has been disclosed. This method allows for
construction of a vinylcyclopropane-fused pyrazolone framework via
a 1,6-addition/substitution sequence providing excellent regio- and
chemoselectivity, good yields, broad functional group tolerance and
gram-scale capacity. Moreover, the subsequent transformation of
derivatives demonstrates great potential in building useful synthetic
architectures.
Introduction
Since the first report of the Wittig reaction in 1953, ylides have
been developed into powerful and versatile synthetic tools in
1
organic chemistry. Ylide chemistry has served as the basis for
constructing various structurally unique, multifunctionalized
2
products and important intermediates. Syntheses based on 1,2-
addition with ylides can rapidly generate various functionalized
3
alkenes (Scheme 1a, upper panel) and small ring compounds
such as epoxides and aziridines (Scheme 1a, lower panel).4
Syntheses based on 1,4-addition with ylides usually exploit highly
chemoselective [2+1] annulation of α,β-unsaturated carbonyl or
imine compounds with ylides to generate multi-substituted
cyclopropane fragments (Scheme 1b, upper panel).5 Using
rationally designed α,β-unsaturated substrates allows the efficient
preparation of numerous five-membered heterocyclic compounds
via a [4+1] pathway instead of a competing [2+1] pathway
(
Scheme 1b, lower panel).6 These heterocyclic compounds
include dihydrofurans, pyrrolines, indolines, oxazolidin-2-ones
and other useful compounds.
Despite significant achievements in ylide addition chemistry,
ylide-initiated remote 1,6-addition/substitution cyclization remains
a challenge, especially for constructing synthetically useful
vinylcyclopropanes7,8 with high chemo- and regio-selectivity
9
(
Scheme 1c). This likely reflects the fact that remote 1,6-
addition/substitution cyclization is much more difficult than 1,2- or
1,4-addition annulation, in part because of the need to ensure
Scheme 1. Different addition patterns of ylide chemistry (X = O or N).
[
[
a]
Ministry of Education Key Laboratory of Standardization of Chinese
Medicine, School of Pharmacy, Chengdu University of Traditional
regioselectivity between the β- and δ-positions due to the
propagation of electronic effects through the conjugated π-
system.10 Robiette and colleagues were the first to present an
Chinese Medicine Chengdu 611137, China.
,
E-mail: huangwei@cdutcm.edu.cn
b]
c]
State Key Laboratory Breeding Base of Systematic Research,
Development and Utilization of Chinese Medicine Resources,
Chengdu University of Traditional Chinese Medicine, Chengdu
effective [2+1] annulation between sulfur ylides and linear α,β,γ,δ-
unsaturated esters, affording versatile vinylcyclopropane
intermediates that could be transformed to functionalized
611137, China.
E-mail: pengcheng@cdutcm.edu.cn
These authors contributed equally to this work.
[
11
cyclopentanoids in one pot. This reaction shows limitations in
substrate compatibility and efficiency, highlighting the need for
more efficient methods for remote cyclization of ylide chemistry.
Supporting information and ORCID(s) from the author(s) for this
article are available on the WWW under https//doi.org/xxxxxx
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European Journal of Organic Chemistry
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Table 1 Optimization of [2 + 1] cyclization conditions.[a]
Entry
Solvent
Base
dr[b]
3a/4a)
Yield[c]
(%)
(
1
2
3
4
5
6
7
8
9
MeCN
THF
K
K
K
K
K
2
2
2
2
2
CO
CO
CO
CO
CO
3
3
3
3
3
60:40
65:35
78:22
75:25
80:20
86:14
88:12
88:12
78:22
88:12
73:27
88:12
86:14
88:12
72
70
81
78
85
89
86
92
85
89
90
92
93
89
DCM
2
Et O
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
Toluene
t-BuOK
KOH
Cs
2
CO
3
Na
2
CO
3
Scheme 2. Selected bioactive compounds containing pyrazolone (a) or
vinylcyclopropane structures (b), and synthesis of vinylcyclopropane-based
pyrazolone (c).
0[d]
1
Cs
Cs
Cs
Cs
Cs
2
2
2
2
2
CO
CO
CO
CO
CO
3
3
3
3
3
11[e]
1
1
1
2[f]
3[g]
4[h]
Vinylcyclopropanes are a privileged skeleton and versatile
synthon in medicinal chemistry, occurring among various
biologically active natural products such as α-Cubebene and
Lumisantonin (Scheme 2a).12 Pyrazolones, for their part, are an
[a] Unless otherwise noted, reactions were performed with 0.1 mmol of 1a,
0.1 mmol of 2a, and 0.12 mmol of base in 2 mL solvent for 8 h at room
temperature. [b] The diastereomeric ratio was determined by H NMR
1
important class of nitrogen-containing units derivatized from
pyrazoles, and they are present in many drugs and bioactive
compounds.13 For example, pyrazolone phenazone, first
synthesized in 1883, is considered the forerunner of synthetic
analgesic and antipyretic drugs.14 Pyrazolone 3-carboxylic acid
skeleton has been used to generate HIV-1 integrase inhibitors
that work effectively at micromolar concentrations (Scheme 2b).15
Merging these two chemical building blocks may lead to a unique
structural motif useful in pharmaceutical and synthetic chemistry.
Although several groups have constructed pyrazolone derivatives
bearing a simple cyclopropane moiety,16 few examples of ylide-
based synthesis of multi-substituted vinylcyclopropane-fused
pyrazolones with high diastereoselectivity have been reported. As
part of our on-going interest in constructing drug-like
spectroscopy of the crude reaction mixture. [c] Total yield of isolated
o
products. [d] The reaction was performed at 40 C. [e] The reaction was
o
performed at -10 C. [f] 1.5 equiv 1a was used. [g] 1.5 equiv 2a was used.
[
h] The reaction was performed for 24 h.
temperature. To our delight, the reaction proceeded smoothly,
delivering the desirable products 4a in 72% yield together with
poor diastereoselectivity (Table 1, entry 1). This initial result
encouraged us to further enhance diastereoselectivity by
investigating solvent effects (entries 2-5). Surprisingly, using
toluene as solvent afforded 4a in 85% yield and sharply improved
diastereoselectivity from 60:40 to as high as 80:20 (entry 5). Next,
we investigated the influence of other reaction parameters,
including bases of different strengths and temperature. The
2 3
strong base Cs CO proved to be optimal for this reaction,
17
frameworks, we describe here the efficient synthesis of multi-
substituted vinylcyclopropane-fused pyrazolones through 1,6-
addition/substitution cyclization involving sulfur ylides and α,β,γ,δ-
unsaturated pyrazolones (Scheme 2c). This reaction allowed to
generate product in high yield with good diastereoselectivity.
generating product in 92% yield with 88:12 dr (entries 6-9).
Increasing reaction temperature to 40 oC led to diastereo-
selectivity as high as at room temperature, but it slightly lowered
o
yield (entry 10). Lowering the temperature to -10 C slowed the
reaction and reduced the dr value appreciably (entry 11).
Moreover, changing the ratio of reagents resulted in almost the
same high yields (entries 12 and 13), albeit with a slight loss in
diastereoselectivity when 1.5 equiv 2a was used (entry 13).
Similarly, extending the reaction time remained the high dr value
together with a little bit of decline in yield (entry 14).
Results and Discussion
Initially, the model reaction of substrate 2a and sulfonium salt 1a
2 3
was carried out in the presence of K CO in MeCN for 8 h at room
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European Journal of Organic Chemistry
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Table 2. Synthesis of vinylcyclopropane-fused pyrazolones 3.[a]
Entry
R1
R2
R3
dr[b]
3/4)
Yield of
isomer 3 (%)
(
1
2
3
4
5
6
7
8
9
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
88:12
86:14
85:15
80:20
80:20
83:17
84:16
82:18
83:17
80:20
85:15
86:14
80 (3a)
71 (3b)
74 (3c)
65 (3d)
61 (3e)
70 (3f)
68 (3g)
65 (3h)
71 (3i)
70 (3j)
76 (3k)
75 (3l)
2-F-Ph
4-F-Ph
2,4-Cl-Ph
3,4-Cl-Ph
4-Br-Ph
2
2-NO -Ph
4-OMe-Ph
Naphthyl
Thienyl
OEt
10
11
12
Me
13
Ph
Ph
78:22
70 (3m)
14
15
16
17
18
19
20
21
22
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
Ph
2-F-Ph
4-F-Ph
2,4-Cl-Ph
3,4-Cl-Ph
4-Br-Ph
4-OMe-Ph
Naphthyl
Ph
Ph
84:16
85:15
78:22
78:22
83:17
82:18
81:19
88:12
87:13
72 (3n)
71 (3o)
61 (3p)
60 (3q)
71 (3r)
67 (3s)
68 (3t)
81 (3u)
79 (3v)
Ph
Ph
Ph
Ph
Ph
Ph
3-Cl-Ph
4-Me-Ph
Ph
[
a] Unless otherwise noted, reactions were performed with 0.1 mmol of 1a, 0.1 mmol of 2a, and 0.12 mmol of Cs
2
CO
3
in 2 mL toluene for 8 h at
1
room temperature. [b] The diastereomeric ratio was determined by H NMR spectroscopy of the crude reaction mixture.
Having established optimal conditions for this remote [2+1]
cyclization reaction, we began to explore its generality and
limitations. Sulfonium salts 1 bearing various substituents with
electron-deficient and -rich aryl groups at different positions were
tolerated well and gave the corresponding products 3a-3i in
outstanding yields with high diastereoselectivities of up to 88:12
efficiency when an ethyoxyl or methyl group was present on R1,
producing the desired product 3k and 3l with high dr values of
85:15 and 86:14, respectively (entry 11-12). Notably, this reaction
also tolerated the disubstituted sulfonium salt with generation of
structurely interesting spiro-indole product 3m with acceptable
diastereoselectivity of 78:22 (entry 13). Next we explored the
possibility of modifying the α,β,γ,δ-unsaturated pyrazolone
(Table 2, entries 1-9). Using a disubstituted aryl group led to yield
similar to that with a monosubstituted aryl group albeit with slightly
lower diastereocontrol (entries 4-5). Besides, sulfonium salt 1
bearing heteroaryl substituent like thienyl group was also
tolerated, providing the desired product 3j with good reaction
performance (entry 10). The reaction proceeded with high
substrate 2. The annulation process tolerated electron-
2
2
withdrawing aryl groups on R (-F, -Cl, -Br, -NO ) as well as an
electron-donating aryl group (-OMe) and a naphthyl group, with dr
values up to 85:15 (entries 14-20). Using disubstituted aryl groups
led to lower yield with moderate diastereoselectivity of 78:22
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European Journal of Organic Chemistry
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(entries 16-17). The reaction was only slightly affected by
changes in the electronic and steric properties of the aryl group
3
on R ; in both cases tested, the desired products 3u and 3v were
obtained in excellent yields (entries 21-22). Moreover, structural
correctness and the relative configuration of both isomers 3/4
were confirmed by X-ray diffraction analysis of representative
products 3r18 and 4k , and the relative configuration of the other
vinylcyclopropane-fused pyrazolones were tentatively assigned
by analogy (Figure 2).
19
During optimization of reaction conditions, we noticed that the
ratio of diastereomers 3a and 4a strongly depended on reaction
temperature and strength of the base present. Lower reaction
temperature or use of a weak base favored the formation of 4a.
We hypothesized that the ratio of 3a to 4a depended on a
20
combination of thermodynamics and kinetics , which we tested
o
by incubating 4a at 60 C in the presence of the strong base
2 3
Cs CO for 4 h. The thermodynamic product 3a was generated in
43% yield, as well as the kinetic product 4a in 57% yield (Scheme
3a). This was consistent with our observation that lower reaction
temperature and weaker base favored synthesis of 4a. Therefore,
we re-optimized reaction conditions, this time with a focus on
enhancing diastereoselectivity towards compound 4a. While the
reaction was conducted in the presence of 2-F-BzOK in MeCN at
Scheme 3. Control experiment of the transformation of compound 4a to 3a (a)
and synthesis of compound 4a (b).
o
the reaction temperature of -45 C, the diastereoisomer 4a was
obtained in 44% yield with a reversed 55:45 dr value (Scheme 3b).
Figure 2. Representative chemical shifts of 1H and 13C NMR in CDCl
, and
3
determination of the relative configuration by single-crystal X-ray analysis of
Figure 1. Representative chemical shifts of 1H and 13C NMR in CDCl
, and
3
determination of the relative configuration by single-crystal X-ray analysis of
product 4k.
product 3r.
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European Journal of Organic Chemistry
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FULL PAPER
Conclusions
In conclusion, we have developed a cyclopropanation of α,β,γ,δ-
unsaturated pyrazolones with sulfonium salts to construct the
vinylcyclopropane-fused pyrazolone framework. The reaction
proceeds via remote 1,6-addition/substitution from novel starting
materials. This approach exhibits good functional group tolerance
as well as excellent regio- and chemoselectivity, and it can be
scaled up to gram synthesis. The products obtained with this
approach can be further transformed into useful synthetic
architectures. Further studies on the bioactivity of the resulting
compounds and on direct asymmetric catalytic versions of the
reaction21 are underway in our laboratories.
Experimental Section
Scheme 4. Gram-scale synthesis of vinylcyclopropane-pyrazolone 3a (a) and
further synthetic transformation of 3a to 5 (b).
1
General Methods: NMR data were obtained for
13C at 100 MHz, or for 1H at 600 MHz and for 13C at 150 MHz. Chemical
shifts are reported in parts per million from tetramethylsilane based on
solvent resonance in CDCl solution as the internal standard. Mass spectra
H at 400 MHz and for
3
Lastly, using these optimal conditions, we performed a gram-
scale reaction of substrate 1a with sulfonium salt 2a. Gratifyingly,
the valuable vinylcyclopropane-pyrazolones 3a smoothly
obtained in respective yields of 77% (Scheme 4a). The resulting
were recorded using ESI as the ionization method. ESI-HRMS spectra
were measured with a Q-TOF instrument. Column chromatography was
performed on silica gel (200-300 mesh) using an eluent of ethyl acetate
and petroleum ether. TLC was performed on glass-backed silica plates;
[
2+1] cyclization product 3a could be subjected to further synthetic
transformation: the structurally unique, pharmacologically
interesting cyclopentene-spiro-pyrazolone derivative was
products were visualized using UV light and I
2
.
5
Preparation of α,β,γ,δ-unsaturated pyrazolones 1:
A
mixture of
rapidly constructed in 54% yield via diastereospecific MgI
catalyzed rearrangement (Scheme 4b).
2
-
hydrazine (3.0 mmol) with ethyl acetoacetate (3.6 mmol, 1.2 equiv) was
refluxed in acetic acid (5 mL) for about 8 h, and left to cool. The pure
product could be obtained by recrystallization by using acetic acid as a
yellow solid, which could be used directly in next step without further
purification. To a solution of the above product in THF (5 mL) under argon
atmosphere was added ethyl (E)-4-oxo-4-arylbut-2-enoate (1.0 equiv) and
pyridine (3.0 equiv). The mixture was stirred at -10 oC followed by addition
of titanium isopropoxide (2.5 equiv). The solution was stirred at room
temperature until the reaction had stopped progressing as observed by
TLC analysis, and then diluted with EtOAc (20 mL) and washed with 1N
aqueous HCl (5 mL), saturated aqueous Na
x 5 mL ). The organic layer was dried over Na
2
CO
3
(2 x 5 mL ), and brine (2
SO , removed under
2
4
reduced pressure, and purified by column chromatography to provide
substrate 1, which were dried under vacuum and analyzed by high-
resolution mass spectrometry.
General procedures for the synthesis of compounds 3: A mixture of
α,β,γ,δ-unsaturated pyrazolone 1 (0.2 mmol) with sulfonium salt 2 (0.2
mmol, 1.0 equiv) was added Cs CO (0.24 mmol, 1.2 equiv) in toluene (2
2 3
mL). The reaction mixture was stirred at room temperature until the
reaction was complete as observed by TLC analysis. Then the solution
was concentrated and the residue was purified by flash chromatography
on silica gel (petroleum ether/ethyl acetate = 6:1) to afford compounds 3,
Scheme 5. Proposed mechanism to explain the transformation of 3a to 5.11
which were dried under vacuum and further analyzed by 1H NMR, 13
NMR and high-resolution mass spectrometry.
C
We hypothesize that 3a is transformed to 5 via the following
reaction mechanism, which is consistent with the pioneering work
of Robiette's group (Scheme 5).11 Highly diastereoselective
rearrangement of vinylcyclopropane-fused pyrazolone to spiro-
Trans-ethyl-2-benzoyl-3-((E)-(3-methyl-5-oxo-1-phenyl-1,5-dihydro-
4
(
H-pyrazol-4-ylid-ene)(phenyl)methyl)cyclopropane-1-carboxylate
3a): yellow solid, 38.3 mg, 80% yield, 88:12 dr, m.p. 106 – 108 oC; 1
H
cyclopentene pyrazolone takes place in the presence of MgI
2
via
3
NMR (400 MHz, CDCl ) δ (ppm) 8.14 – 8.07 (m, 2H), 7.83 – 7.75 (m, 2H),
a
ring-opening step. Subsequent diastereocontrolled
7
.56 – 7.52(m, 1H), 7.48 – 7.43 (m, 5H), 7.37 – 7.32 (m, 3H), 7.14 (t, J =
spirocyclopentenation involving intra-molecular SN
generates 5.
2
alkylation
7.2 Hz, 1H), 4.18 (q, J = 7.2 Hz, 2H), 4.02 (dd, J = 10.0, 5.2 Hz, 1H ), 3.84
(dd, J = 10.0, 6.8 Hz, 1H), 2.48 (dd, J = 7.2, 5.6 Hz, 1H), 1.54 (s, 3H), 1.26
(
t, J = 7.2 Hz, 3H); 13C NMR (100 MHz, CDCl
3
) δ (ppm) 194.6, 170.8, 162.6,
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European Journal of Organic Chemistry
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FULL PAPER
1
1
60.2, 148.0, 138.0, 137.6, 137.0, 133.3, 129.6, 128.8, 128.7, 128.6, 128.5,
Trans-ethyl-2-((E)-(3-methyl-5-oxo-1-phenyl-1,5-dihydro-4H-pyrazol-
4-ylidene)(phenyl)methyl)-3-(2-nitrobenzoyl)cyclopropane-1-
carboxylate (3g): yellow solid, 35.6 mg, 68% yield, 84:16 dr, m.p. 156 –
28.1, 124.8, 118.9, 61.4, 37.4, 35.5, 30.7, 17.1, 14.2; HRMS (ESI) m/z
+
calcd for C30
26
H N
2
O
4
Na 501.1790, found 501.1789.
o
1
1
7
58 C; H NMR (600 MHz, CDCl
.88 – 7.86 (m, 2H), 7.65 – 7.56 (m, 4H), 7.50 – 7.49 (m, 4H), 7.41 – 7.38
3
) δ (ppm) 8.0 (dd, J = 7.8, 1.2 Hz, 1H),
Trans-ethyl-2-(2-fluorobenzoyl)-3-((E)-(3-methyl-5-oxo-1-phenyl-1,5-
dihydro-4H-pyrazol-4-ylidene)(phenyl)methyl)cyclopropane-1-
carboxylate (3b): yellow solid, 35.3 mg, 71% yield, 86:18 dr, m.p. 158 –
1
7
7
9
7
1
(m, 2H), 7.20 – 7.17 (m, 1H), 4.20 – 4.16 (m, 2H), 3.63 (dd, J = 9.6, 5.4
Hz, 1H), 3.56 (dd, J = 9.6, 7.8 Hz, 1H), 2.47 (dd, J = 7.8, 5.4 Hz, 1H), 1.64
60 oC; 1H NMR (600 MHz, CDCl
3
) δ (ppm) 7.82 – 7.77 (m, 3H), 7.50 –
s, 3H), 1.26 (t, J = 7.2 Hz, 3H); 13C NMR (150 MHz, CDCl
3
) δ (ppm) 196.6,
(
.46 (m, 5H), 7.36 – 7.33 (m, 2H), 7.17 (td, J = 7.2, 0.6 Hz, 1H), 7.15 –
.11 (m, 2H), 4.19 (q, J = 6.6 Hz, 2H), 4.01 – 3.98 (m, 1H), 3.66 (dd, J =
.6, 7.2 Hz, 1H), 2.35 (dd, J = 7.2, 4.8 Hz, 1H), 1.69 (s, 3H), 1.26 (t, J =
1
1
1
5
70.4, 162.7, 160.2, 148.4, 146.6, 138.2, 137.9, 136.4, 133.9, 131.2, 129.8,
29.2, 128.9, 128.6, 128.3, 125.0, 124.3, 118.8, 61.6, 40.7, 36.5, 33.1,
+
7.2, 14.3; HRMS (ESI) m/z calcd for C30
25
H N
O
3 6
Na : 546.1641, found
.2 Hz, 3H); 13C NMR (150 MHz, CDCl
61.5 (d, JCF = 254.9 Hz), 160.3, 148.2, 138.2, 138.0, 134.7 (d, JCF = 8.9
3
) δ (ppm) 193.1, 170.7, 162.5,
46.1640.
Hz), 130.8 (d, JCF = 1.7 Hz), 129.6, 128.8, 128.3, 126.2 (d, JCF = 11.3 Hz),
Trans-ethyl-2-(4-methoxybenzoyl)-3-((E)-(3-methyl-5-oxo-1-phenyl-
1,5-dihydro-4H-py-razol-4-ylidene)(phenyl)methyl)cyclopropane-1-
carboxylate (3h): yellow solid, 33.1 mg, 65 % yield, 82:18 dr, m.p. 133 –
1
1
5
24.8, 124.4 (d, JCF = 3.5 Hz), 118.8, 116.8, 61.4, 40.4, 35.6, 32.0, 17.2,
4.3; HRMS (ESI) m/z calcd for C30H25FN2O4Na+ 519.1696, found
19.1695.
135 oC; 1H NMR (600 MHz, CDCl
3
) δ (ppm) 8.10 – 8.08 (m, 2H), 7.79 –
7
6
3
=
1
1
.78 (m, 2H), 7.46 – 7.45 (m, 3H), 7.37 – 7.32 (m, 4H), 7.15 – 7.13 (m, 1H),
Trans-ethyl-2-(4-fluorobenzoyl)-3-((E)-(3-methyl-5-oxo-1-phenyl-1,5-
dihydro-4H-pyrazol-4-ylidene)(phenyl)methyl)cyclopropane-1-
carboxylate (3c): yellow solid, 36.7 mg, 74% yield, 85:15 dr, m.p. 156 –
.93 – 6.91 (m, 2H), 4.20 – 4.16 (m, 2H), 3.96 (dd, J = 10.2, 5.4 Hz, 1H),
.86 – 3.83 (m, 4H), 2.48 (dd, J = 7.2, 5.4 Hz, 1H), 1.52 (s, 3H), 1.26 (t, J
7.2 Hz, 3H); 13C NMR (150 MHz, CDCl
3
) δ (ppm) 192.6, 171.0, 163.7,
1
7
4
58 oC; 1H NMR (600 MHz, CDCl
3
) δ (ppm) 8.16 – 8.12 (m, 2H), 7.78 –
.76 (m, 2H), 7.48 – 7.45 (m, 3H), 7.37 – 7.34 (m, 4H), 7.16 – 7.10 (m, 3H),
.20 – 4.16 (m, 2H), 3.96 (dd, J = 9.6, 5.4 Hz, 2H), 3.80 (dd, J = 10.2, 7.2
62.6, 160.7, 148.0, 138.1, 137.5, 131.2, 123.0, 129.5, 128.7, 128.3, 128.0,
24.7, 118.8, 113.7, 61.3, 55.5, 37.2, 35.2, 30.1, 17.0, 14.2; HRMS (ESI)
+
m/z calcd for C31
H N
28 2
O
5
Na : 531.1896, found 531.1896.
Hz, 1H), 2.47 (dd, J = 7.2, 5.4 Hz, 1H), 1.54 (s, 3H), 1.26 (t, J = 7.2 Hz,
3
2
H); 13C NMR (150 MHz, CDCl
53.8 Hz), 162.7, 161.5, 160.3, 148.1, 138.2, 138.0, 133.5 (d, JCF = 3.0
3
) δ (ppm) 193.1, 170.8, 166.0 (d, JCF
=
Trans-ethyl-2-(2-naphthoyl)-3-((E)-(3-methyl-5-oxo-1-phenyl-1,5-
dihydro-4H-pyrazol-4-ylidene)(phenyl)methyl)cyclopropane-1-
carboxylate (3i): yellow solid, 37.5 mg, 71% yield, 83:17 dr, m.p. 158 –
Hz), 131.6 (d, JCF = 9.3 Hz), 129.7, 128.8, 128.6, 128.2, 124.9, 118.9,
1
m/z calcd for C30
o
1
15.7 (d, JCF = 21.9 Hz), 61.5, 37.3, 35.6, 30.7,17.1, 14.3; HRMS (ESI)
160 C; H NMR (600 MHz, CDCl
3
) δ (ppm) 8.82 – 8.81 (m, 1H), 8.04 (dd,
+
H25FN
2 4
O
Na : 519.1696, found 519.1698.
J = 8.4, 1.8 Hz, 1H), 8.02 (d, J = 8.4 Hz, 1H), 7.86 (dd, J = 10.8, 8.4 Hz,
2
7
4
=
H), 7.76 – 7.74 (m, 2H), 7.61 – 7.57 (m, 1H), 7.54 – 7.51 (m, 1H), 7.48 –
.47 (m, 3H), 7.33 – 7.29 (m, 4H), 7.12 – 7.10 (m, 1H), 4.23 – 4.19 (m, 2H),
.16 (dd, J = 10.2, 5.4 Hz, 1H), 3.96 (dd, J = 10.2, 6.6 Hz, 1H), 2.57 (dd, J
6.6, 5.4 Hz,1H), 1.52 (s, 3H), 1.28 (t, J = 7.2 Hz, 3H); 13C NMR (150 MHz,
Trans-ethyl-2-(2,4-dichlorobenzoyl)-3-((E)-(3-methyl-5-oxo-1-phenyl-
,5-dihydro-4H-pyrazol-4-ylidene)(phenyl)methyl)cyclopropane-1-
carboxylate (3d): yellow solid, 35.6 mg, 65% yield, 80:20 dr, m.p. 165 –
1
o
1
1
67 C; H NMR (600 MHz, CDCl
J = 8.4 Hz, 1H), 7.50 – 7.45 (m, 4H), 7.40 – 7.37 (m, 3H), 7.28 – 7.26 (m,
H), 7.19 – 7.16 (m, 1H), 4.20 – 4.16 (m, 2H), 3.84 – 3.82 (m, 1H), 3.58
dd, J = 9.6, 7.2 Hz, 1H), 2.35 – 2.33 (m, 1H), 1.62 (s, 3H), 1.25 (t, J = 7.2
Hz, 3H); 13C NMR (150 MHz, CDCl
) δ (ppm) 195.6, 170.4, 162.6, 159.9,
48.3, 138.1, 137.9, 136.5, 132.7, 131.4, 130.5, 129.7, 128.9, 128.5, 128.3,
3
) δ (ppm) 7.83 – 7.81 (m, 2H), 7.69 (d,
CDCl
3
) δ (ppm) 194.3, 171.0, 162.8, 160.5, 148.1, 138.1, 137.5, 135.8,
1
1
34.3, 132.6, 131.4, 129.9, 129.7, 128.8, 128.6, 128.5, 128.2, 127.8, 126.9,
24.8, 124.1, 118.9, 61.5, 37.6, 35.5, 30.4, 17.1, 14.3; HRMS (ESI) m/z
2
(
+
calcd for C34
28
H N
2
O
4
Na : 551.1947, found 551.1948.
3
1
1
Trans-ethyl-2-((E)-(3-methyl-5-oxo-1-phenyl-1,5-dihydro-4H-pyrazol-
4ylidene)(phenyl)methyl)-3-(thiophene-2-carbonyl)cyclopropane-1-
carboxylate (3j): yellow solid, 33.9 mg, 70% yield, 80:20 dr, m.p. 150 –
27.4, 124.9, 118.8, 61.5, 40.9, 36.2, 32.8, 17.2, 14.3; HRMS (ESI) m/z
+
calcd for C30
H24Cl
2 2
N O
4
Na : 569.1011, found 569.1012.
o
1
1
51 C; H NMR (600 MHz, CDCl
3
) δ (ppm) 8.05 (d, J = 2.4 Hz, 1H), 7.76 (d,
Trans-ethyl-2-(3,4-dichlorobenzoyl)-3-((E)-(3-methyl-5-oxo-1-phenyl-
,5-dihydro-4H-pyrazol-4-ylidene)(phenyl)methyl)cyclopropane-1-
carboxylate (3e): yellow solid, 33.4 mg, 61% yield, 80:20 dr, m.p. 152 –
J = 7.8 Hz, 2H), 7.64 (d, J = 4.2 Hz, 1H), 7.46 (bro, s, 3H), 7.35 (t, J = 6.6 Hz,
1
4
3
3
H), 7.14 (d, J = 4.8 Hz, 2H), 4.19 – 4.18 (m, 2H), 3.93 (dd, J = 9.6, 4.8 Hz, 1H),
.75 (t, J = 9.6 Hz, 1H), 2.43 (t, J = 4.8 Hz, 1H), 1.55 (s, 3H), 1.26 (t, J = 6.6 Hz,
o
1
1
54 C; H NMR (600 MHz, CDCl
3
) δ (ppm) 8.21 (d, J = 1.8 Hz, 1H), 7.95
H); 13C NMR (150 MHz, CDCl
3
) δ (ppm) 186.7, 170.8, 162.6, 159.9, 148.1,
(dd, J = 8.4, 1.8 Hz, 1H), 7.80 – 7.78 (m, 2H), 7.53 (d, J = 7.8Hz, 1H), 7.49
1
6
5
43.8, 138.1, 137.6, 134.5, 134.0, 129.6, 128.8, 128.6, 128.5, 128.2, 124.8, 119.0,
1.5, 37.7, 35.2, 30.5, 17.1, 14.3; HRMS (ESI) m/z calcd for C28
07.1354, found 507.1352.
–
1
7
3
1
1
7.47 (m, 3H), 7.38 – 7.35 (m, 2H), 7.33 – 7.32 (m, 2H), 7.17 – 7.14 (m,
H), 4.21 – 4.15 (m, 2H), 3.92 (dd, J = 9.6, 5.4 Hz, 1H), 3.79 (dd, J = 9.6,
.2 Hz, 1H), 2.47 (dd, J = 7.2, 5.4 Hz, 1H), 1.55 (s, 3H), 1.26 (t, J = 6.6 Hz,
SNa+:
24 2 4
H N O
H); 13C NMR (150 MHz, CDCl
Trans-diethyl-3-((E)-(3-methyl-5-oxo-1-phenyl-1,5-dihydro-4H-
pyrazol-4-ylidene)(phenyl)methyl)cyclopropane-1,2-dicarboxylate
(3k): yellow solid, 33.9 mg, 76% yield, 85:15 dr, m.p. 124 – 126 oC; 1
H
3
) δ (ppm) 192.7, 170.6, 162.6, 159.5, 148.1,
38.0 138.0, 137.5, 136.6, 133.3, 130.9, 130.7, 129.8, 128.9, 128.7, 128.2,
28.0, 125.0, 118.8, 61.6, 37.2, 35.9, 30.9, 17.1, 14.3; HRMS (ESI) m/z
+
calcd for C30
H24Cl
2 2
N O
4
Na : 569.1011, found 569.1009.
3
NMR (600 MHz, CDCl ) δ (ppm) 7.94 – 7.92 (m, 2H), 7.47 – 7.45 (m, 3H),
7
7
.41 – 7.38 (m, 2H), 7.34 (s, bro, 2H), 7.17 (t, J = 7.2 Hz, 1H), 4.15 (q, J =
.2 Hz, 2H), 4.08 – 4.01 (m, 2H), 3.48 (dd, J = 9.6, 7.2 Hz, 1H), 3.05 (dd,
Trans-ethyl-2-(4-bromobenzoyl)-3-((E)-(3-methyl-5-oxo-1-phenyl-1,5-
dihydro-4H-pyrazol-4-ylidene)(phenyl)methyl)cyclopropane-1-
carboxylate (3f): yellow solid, 39.0 mg, 70% yield, 83:17 dr, m.p. 133 –
J = 9.6, 5.4 Hz, 1H), 2.16 (dd, J = 7.2, 5.4 Hz, 1H), 1.58 (s, 3H), 1.24 (t, J
7.2 Hz, 3H), 1.17 (t, J = 7.2 Hz, 3H); 13C NMR (150 MHz, CDCl
=
1
1
3
) δ (ppm)
o
1
1
7
7
=
1
1
1
3
35 C; H NMR (600 MHz, CDCl ) δ (ppm) 7.97 (dt, J = 9.0, 2.4 Hz, 2H),
70.5, 169.5, 162.6, 159.5, 148.2, 138.3, 137.8, 129.6, 128.9, 128.9, 128.2,
.77 – 7.75 (m, 2H), 7.59 (dt, J = 9.0, 1.2 Hz, 2H), 7.48 – 7.46 (m, 3H),
.38 – 7.34 (m, 4H), 7.17 – 7.14 (m, 1H), 4.20 – 4.16 (m, 2H), 3.95 (dd, J
10.2, 5.4 Hz, 1H), 3.79 (dd, J = 10.2, 7.2 Hz), 2.47 (dd, J = 7.2, 5.4 Hz),
24.9, 118.8, 61.4, 61.4, 33.0, 32.9, 29.5, 17.2, 14.2; HRMS (ESI) m/z
+
calcd for C26
26
H N
2
O
5
Na : 469.1739, found 469.1741.
.54 (s, 3H), 1.26 (t, J = 7.2 Hz); 13C NMR (150 MHz, CDCl
Trans-ethyl-2-acetyl-3-((E)-(3-methyl-5-oxo-1-phenyl-1,5-dihydro-4H-
pyrazol-4-ylidene)(phenyl)methyl)cyclopropane-1-carboxylate (3l):
yellow solid, 31.2 mg, 75% yield, 86:14 dr, m.p. 118 – 120 oC; 1H NMR
3
) δ (ppm) 193.7,
70.8, 162.6, 159.9, 148.1, 138.1, 137.6, 135.8, 131.9, 130.4, 129.7, 128.9,
28.7, 128.6, 128.2, 124.9, 118.9, 61.5, 37.3, 35.7, 30.8, 17.1, 14.3; HRMS
+
(ESI) m/z calcd for C30H25BrN
O
2 4
Na : 579.0895, found 579.0897.
3
(600 MHz, CDCl ) δ (ppm) 7.90 (d, J = 7.8 Hz, 1H), 7.47 – 7.45 (m, 2H),
This article is protected by copyright. All rights reserved.

European Journal of Organic Chemistry
10.1002/ejoc.201800710
FULL PAPER
7
–
1
1
4
.43 – 7.38 (m, 1H), 7.18 (t, J = 7.8 Hz, 1H), 4.15 (q, J = 7.2 Hz, 1H), 3.41
3.35 (m, 1H), 2.35 (s, 2H), 2.12 (dd, J = 6.0, 6.6 Hz, 1H), 1.59 (s, 3H),
4.05 (dd, J = 9.6, 5.4 Hz, 1H), 3.69 – 3.67 (m, 1H), 2.37 (dd, J = 6.6, 2.4
Hz, 1H), 1.64 (s, 3H), 1.28 (t, J = 7.2 Hz, 3H); 13C NMR (150 MHz, CDCl
3
)
.24 (t, J = 7.2 Hz, 2H); 13C NMR (150 MHz, CDCl
δ (ppm) 195.0, 170.6, 162.2, 156.6, 147.2, 137.9, 137.6, 136.9, 134.0,
3
) δ (ppm) 203.4, 170.7,
62.6, 160.2, 148.2, 138.1, 129.6, 128.9, 128.3, 128.2, 125.0, 119.0, 61.4,
133.6, 129.1, 128.9, 128.8, 128.7, 128.5, 125.0, 118.9, 61.7, 37.4, 31.3,
+
0.4, 35.0, 31.3, 30.9, 17.2, 14.2; HRMS (ESI) m/z calcd for
17.5, 14.3; HRMS (ESI) m/z calcd for C30
H24Cl
N
2 2
O
4
Na : 569.1011, found
+
C
25
H
24
N
2
O
4
Na : 439.1634, found 439.1636.
569.1012.
Trans-ethyl-1'-methyl-3-((E)-(3-methyl-5-oxo-1-phenyl-1,5-dihydro-
H-pyrazol-4-ylidene)(phenyl)methyl)-2'-oxospiro[cyclopropane-1,3'-
indoline]-2-carboxylate (3m): yellow solid, 35.3 mg, 70% yield, 78:22 dr,
m.p. 160 – 161 oC; 1H NMR (600 MHz, CDCl
) δ (ppm) 7.71 (d, J = 7.6
Hz, 1H), 7.47 – 7.44 (m, 3H), 7.35 – 7.29 (m, 1H), 7.12 – 7.07 (m, 1H),
Trans-ethyl-2-benzoyl-3-((E)-(4-bromophenyl)(3-methyl-5-oxo-1-
phenyl-1,5-dihydro-4H-pyrazol-4-ylidene)methyl)cyclopropane-1-
carboxylate (3r): yellow solid, 39.6 mg, 71% yield, 83:17 dr, m.p. 182 –
4
o
1
3
3
184 C; H NMR (600 MHz, CDCl ) δ (ppm) 8.06 (dd, J = 7.8, 0.6 Hz, 2H),
7.76 (dd, J = 9.0, 1.2 Hz, 2H), 7.63 (d, J = 9.0 Hz, 2H), 7.57 – 7.54 (m, 1H),
7.47 – 745 (m, 2H), 7.36 – 7.33 (m, 4H), 7.15 – 7.13 (m, 1H), 4.22 – 4.16
(m, 2H), 4.04 (dd, J = 10.2, 5.4 Hz, 1H), 3.75 (dd, J = 9.6, 7.2 Hz, 1H), 2.40
(dd, J = 7.2, 5.4 Hz, 1H), 1.59 (s, 3H), 1.27 (t, J = 7.2 Hz, 3H); 13C NMR
6
1
3
1
1
.89 (d, J = 7.2 Hz, 1H), 4.11 – 4.09 (m, 1H), 4.06 – 4.05 (d, J = 9.0 Hz,
H), 3.20 (s, 3H), 2.60 (d, J = 9.0 Hz, 1H), 1.25 (s, 3H), 1.14 (t, J = 7.2 Hz,
H); 13C NMR (150 MHz, CDCl
3
) δ (ppm) 192.6, 172.2, 171.4, 162.6, 156.1,
42.3, 130.3, 129.1, 128.8, 128.8, 128.6, 128.0, 126.5, 124.9, 124.0, 119.4,
(150 MHz, CDCl
136.6, 133.5, 131.5, 128.9, 128.8, 128.7, 128.7, 124.9, 124.1, 118.9, 61.6,
37.5, 35.4, 31.0, 17.4, 14.3; HRMS (ESI) m/z calcd for C30
Na+:
79.0895, found 579.0893.
3
) δ (ppm) 195.0, 170.7, 162.4, 158.6, 147.6, 138.0, 137.0,
19.1, 100.0, 60.7, 40.6, 35.5, 29.8, 19.7, 17.7, 16.4; HRMS (ESI) m/z
+
27
calcd for C31H N
3
4
O Na : 528.1899, found 528.1896.
2 4
H25BrN O
5
Trans-ethyl-2-benzoyl-3-((E)-(2-fluorophenyl)(3-methyl-5-oxo-1-
phenyl-1,5-dihydro-4H-pyrazol-4-ylidene)methyl)cyclopropane-1-
carboxylate (3n): yellow solid, 35.6 mg, 72% yield, 84:16 dr, m.p. 122 –
Trans-ethyl-2-benzoyl-3-((E)-(4-methoxyphenyl)(3-methyl-5-oxo-1-
phenyl-1,5-dihydro-4H-pyrazol-4-ylidene)methyl)cyclopropane-1-
carboxylate (3s): yellow solid, 34.1 mg, 67% yield, 82:18 dr, m.p. 170 –
o
1
1
7
7
7
4
3
24 C; H NMR (600 MHz, CDCl ) δ (ppm) 8.10 (dd, J = 7.8, 0.6 Hz, 2H),
72 oC; 1H NMR (600 MHz, CDCl
1
7
7
–
9
7
1
1
3
) δ (ppm) 8.11 – 8.09 (m, 2H), 7.80 –
.75 (dd, J = 8.4, 1.2 Hz, 2H), 7.57 – 7.54 (m, 1H), 7.51 – 7.48 (m, 2H),
.48 – 7.45 (m, 2H), 7.36 – 7.33 (m, 2H), 7.28 (td, J = 7.8, 1.2 Hz, 1H),
.21 (td, J = 8.4, 1.2 Hz, 1H), 7.15 – 7.12 (m, 1H), 4.20 – 4.16 (m, 2H),
.05 (dd, J = 10.2, 5.4 Hz, 1H), 3.78 – 3.75 (m, 1H), 2.36 (dd, J = 7.2, 6.4
.78 (m, 2H), 7.55 – 7.52 (m, 1H), 7.46 – 7.44 (m, 2H), 7.37 – 7.33 (m, 2H),
.26 (d, J = 9.0 Hz, 2H), 7.15 – 7.12 (m, 1H), 6.99 (d, J = 8.4 Hz, 2H), 4.22
4.18 (m, 2H), 4.02 (dd, J = 9.6, 5.4 Hz, 1H), 3.89 (s, 3H), 3.81 (dd, J =
.6, 6.6 Hz, 1H), 2.53 (dd, J = 6.6, 5.4 Hz, 1H), 1.62 (s, 3H), 1.28 (t, J =
Hz, 1H), 1.62 (s, 3H), 1.25 (t, J = 7.2 Hz, 3H); 13C NMR (150 MHz, CDCl
δ (ppm) 195.3, 170.7, 162.2, 159.0 (d, JCF = 247.2 Hz), 154.8, 147.5, 138.0,
3
)
.2 Hz, 3H); 13C NMR (150 MHz, CDCl
3
) δ (ppm) 194.7, 170.9, 162.9,
61.0, 160.6, 148.2, 138.2, 137.1, 133.4, 130.0, 128.9, 128.8, 128.6, 128.1,
24.8, 118.9, 61.4, 55.5, 37.4, 35.8, 30.8, 17.4, 14.3; HRMS (ESI) m/z
1
1
37.1, 133.5, 133.0, 132.5 (d, JCF = 2.3 Hz), 132.0 (d, JCF = 8.0 Hz), 129.7,
28.9, 128.6, 124.9, 123.7 (d, JCF = 3.3 Hz), 118.9, 115.7 (d, JCF = 20.7
+
calcd for C31
28
H N
2
O
5
Na : 531.1896, found 531.1898.
Hz), 61.4, 37.3, 35.5, 30.8, 17.0, 14.3; HRMS (ESI) m/z calcd for
+
30
C H
25FN
2
O
4
Na : 519.1696, found 519.1694.
Trans-ethyl-2-benzoyl-3-((E)-(3-methyl-5-oxo-1-phenyl-1,5-dihydro-
H-pyrazol-4-ylid-ene)(naphthalen-1-yl)methyl)cyclopropane-1-
carboxylate (3t): yellow solid, 36 mg, 68% yield, 81:19 dr, m.p. 137 – 139
4
Trans-ethyl-2-benzoyl-3-((E)-(4-fluorophenyl)(3-methyl-5-oxo-1-
phenyl-1,5-dihydro-4H-pyrazol-4-ylidene)methyl)cyclopropane-1-
carboxylate (3o): yellow solid, 35.3 mg, 71% yield, 85:15 dr, m.p. 158 –
o
1
C; H NMR (600 MHz, CDCl
3
) δ (ppm) 8.12 – 8.10 (m, 2H), 7.96 (d, J =
.4 Hz, 1H), 7.94 – 7.92 (m, 2H), 7.86 (s, bro, 1H), 7.80 – 7.78 (m, 2H),
.61 – 7.58 (m, 2H), 7.57 – 7.54 (m, 1H), 7.48 – 7.45 (m, 3H), 7.38 – 7.34
8
7
o
1
1
7
60 C; H NMR (600 MHz, CDCl
3
) δ (ppm) 8.09 (dd, J = 8.4, 1.2 Hz, 2H),
.77 – 7.75 (m, 2H), 7.57 – 7.54 (m, 1H), 7.47 – 7.44 (m, 2H), 7.37 – 7.33
(m, 2H), 7.16 – 1.13 (m, 1H), 4.18 (q, J = 7.2 Hz, 2H), 4.07 (dd, J = 10.2,
(m, 4H), 7.18 (t, J = 9.0 Hz, 2H), 7.15 – 7.13 (m, 1H), 4.21 – 4.16 (m, 2H),
5
1
1
1
.4 Hz, 1H), 3.87 (dd, J = 10.2, 7.2 Hz, 1H), 2.48 (s, bro, 1H), 1.52 (s, 3H),
.25 (t, J = 7.2 Hz, 3H); 13C NMR (150 MHz, CDCl
) δ (ppm) 194.8, 171.0,
62.7, 160.3, 148.1, 138.2, 137.1, 133.5, 133.4, 132.4, 128.9, 128.8, 128.7,
4
=
.03 (dd, J = 10.2, 5.4 Hz, 1H), 3.78 (dd, J = 9.6, 7.2 Hz, 1H), 2.42 (dd, J
7.8, 5.4 Hz, 1H), 1.58 (s, 3H), 1.27 (t, J = 7.2 Hz, 3H); 13C NMR (150
3
MHz, CDCl
3
) δ (ppm) 194.9, 170.8, 163.5 (d, JCF = 248.7 Hz), 162.5, 159.0,
28.6, 128.0, 127.4, 127.0, 124.8, 118.9, 61.5, 37.5, 31.1, 17.4, 14.3;
1
1
C
47.7, 138.1, 137.0, 133.7, 133.5 (d, JCF = 3.6 Hz), 128.9, 128.8, 128.7,
+
HRMS (ESI) m/z calcd for C34
H
N
28 2
O
4
Na : 551.1947, found 551.1945.
24.9, 118.9, 61.5, 37.5, 35.6, 31.0, 17.3, 14.3; HRMS (ESI) m/z calcd for
+
30
H
25FN
2
O
4
Na : 519.1696, found 519.1698.
Trans-ethyl-2-benzoyl-3-((E)-(1-(3-chlorophenyl)-3-methyl-5-oxo-1,5-
dihydro-4H-pyrazol-4-ylidene)(phenyl)methyl)cyclopropane-1-
carboxylate (3u): yellow solid, 41.6 mg, 81% yield, 88:12 dr, m.p. 125 –
Trans-ethyl-2-benzoyl-3-((E)-(2,4-dichlorophenyl)(3-methyl-5-oxo-1-
phenyl-1,5-di-hydro-4H-pyrazol-4-ylidene)methyl)cyclopropane-1-
carboxylate (3p): yellow solid, 33.4 mg, 61% yield, 78:22 dr, m.p. 168 –
o
1
1
7
28 C; H NMR (600 MHz, CDCl
3
) δ (ppm) 8.09 (dd, J = 8.4, 1.2 Hz, 2H),
.85 (t, J = 1.8 Hz, 1H), 7.72 (ddd, J = 8.4, 2.4, 1.2 Hz, 1H), 7.57 – 7.54
1
7
1
4
7
70 oC; 1H NMR (600 MHz, CDCl
3
) δ (ppm) 8.11 – 8.09 (m, 2H), 7.76 –
(
7
m, 1H), 7.49 – 7.45 (m, 5H), 7.39 – 7.32 (m, 2H), 7.26 (t, J = 7.8Hz, 1H),
.09 (ddd, J = 8.4, 2.4, 1.2Hz, 1H), 4.18 (qd, J = 7.2, 2.4 Hz, 2H), 4.03 (dd,
J = 10.2, 5.4 Hz, 1H), 3.79 (dd, J = 9.6, 6.6 Hz, 1H), 2.46 (dd, J = 8.4, 6.6
Hz, 1H), 1.54 (s, 3H), 1.26 (t, J = 7.2 Hz, 3H); 13C NMR (150 MHz, CDCl
δ (ppm) 194.6, 170.8, 162.6, 161.0, 148.5, 139.1, 137.5, 136.9, 134.4,
.74 (m, 2H), 7.58 – 7.54 (m, 3H), 7.49 – 7.45 (m, 2H), 7.41 (dd, J = 7.8,
.8 Hz, 1H), 7.36 – 7.33 (m, 2H), 7.16 – 7.13 (m, 1H), 4.22 – 4.16 (m, 2H),
.07 (dd, J = 9.6, 5.4 Hz, 1H), 3.77 (dd, J = 9.6, 7.2 Hz, 1H), 2.26 (dd, J =
.2, 5.4 Hz, 1H), 1.58 (s, 3H), 1.26 (t, J = 7.2 Hz, 3H); 13C NMR (150 MHz,
3
)
CDCl
3
) δ (ppm) 195.4, 170.6, 162.1, 155.7, 147.2, 137.9, 137.0, 136.4,
1
3
5
33.4, 129.7, 129.7,128.8, 128.6, 128.1,128.1, 124.6, 118.5, 116.4, 61.4,
1
6
C
34.8, 133.6, 133.3, 132.8, 129.6, 128.9, 128.8, 128.7, 126.8, 125.0, 118.9,
Na+:
7.4, 35.5, 30.7, 17.0, 14.2; HRMS (ESI) m/z calcd for C30
35.1401, found 535.1402.
H25ClN O
2 4
1.5, 37.8, 35.4, 30.7, 17.0, 14.3; HRMS (ESI) m/z calcd for
+
30
H
24Cl
2
N
O
2 4
Na : 569.1011, found 569.1013.
Trans-ethyl-2-benzoyl-3-((E)-(3-methyl-5-oxo-1-(p-tolyl)-1,5-dihydro-
Trans-ethyl-2-benzoyl-3-((E)-(3,4-dichlorophenyl)(3-methyl-5-oxo-1-
phenyl-1,5-dihy-dro-4H-pyrazol-4-ylidene)methyl)cyclopropane-1-
carboxylate (3q): yellow solid, 32.9 mg, 60% yield, 78:22 dr, m.p. 155 –
4
(
H-pyrazol-4-ylidene)(phenyl)methyl)cyclopropane-1-carboxylate
3v): yellow solid, 38.9 mg, 79% yield, 87:13 dr, m.p. 119 – 122 oC; 1
H
3
NMR (600 MHz, CDCl ) δ (ppm) 8.11-8.09 (m, 2H), 7.65 – 7.63 (m, 2H),
o
1
1
7
7
3
57 C; H NMR (600 MHz, CDCl ) δ (ppm) 8.07 (dd, J = 7.8, 1.2 Hz, 2H),
.74 – 7.72 (m, 2H), 7.58 – 7.55 (m, 3H), 7.47 (t, J = 7.8 Hz, 2H), 7.36 –
.33 (m, 2H), 7.26 (s, 1H), 7.16 – 7.13 (m, 1H), 4.20 (q, J = 7.2 Hz, 2H),
7
8
.55 – 7.52 (m, 1H), 7.47 – 7.44 (m, 5H), 7.35 – 7.33 (m, 2H), 7.15 (d, J =
.4 Hz, 2H), 4.20 – 4.12 (m, 2H), 4.01 (dd, J = 10.2, 5.4 Hz, 1H), 3.84 (dd,
J = 9.6, 7.2 Hz, 1H), 2.47 (dd, J = 7.2, 5.4 Hz, 1H), 2.32 (s, 3H), 1.53 (s,
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European Journal of Organic Chemistry
10.1002/ejoc.201800710
FULL PAPER
3
1
1
H), 1.25 (t, J = 7.2 Hz, 3H); 13C NMR (150 MHz, CDCl
70.9, 162.5, 160.1, 147.9, 137.7, 137.1, 135.7, 134.5, 133.4, 129.6, 129.3,
3
) δ (ppm) 194.7,
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+
HRMS (ESI) m/z calcd for C31
H N
28 2
O
4
Na : 515.1947, found 515.1945.
Synthesis of compound 4a: A mixture of α,β,γ,δ-unsaturated pyrazolone
a (72.5 mg, 0.2 mmol) with sulfonium salt 2a (52.2 mg, 0.2 mmol) was
1
added 2-F-BzOK (33.6 mg, 0.24 mmol) in MeCN (2 mL) at -45 oC. The
reaction mixture was stirred at -45 oC until the reaction was complete as
observed by TLC analysis. Then the solution was concentrated and the
residue was purified by flash chromatography on silica gel (petroleum
ether/ethyl acetate = 4:1) to afford compounds 4a, which were dried under
vacuum and further analyzed by 1H NMR, 13C NMR and high-resolution
mass spectrometry.
30, 50-61; g) D. Seidel, Acc.Chem. Res. 2015, 48, 317-328; h) G. Qiu,
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Cis-ethyl-2-benzoyl-3-((E)-(3-methyl-5-oxo-1-phenyl-1,5-dihydro-4H-
pyrazol-4-ylid-ene)(phenyl)methyl)cyclopropane-1-carboxylate
yellow solid, 21.1 mg, 44% yield, 55:45 dr, m.p. 139 – 141 oC; 1H NMR
4a:
1708-1711.
(
1
7
400 MHz, CDCl ) δ (ppm) 7.96 (d, J = 1.2 Hz, 1H), 7.94 (d, J = 0.8 Hz,
H), 7.92 (d, J = 0.8 Hz, 1H), 7.91 (d, J = 1.6 Hz, 1H), 7.56 – 7.50 (m, 4H),
.45 – 7.36 (m, 4H), 7.20 – 7.14 (m, 3H), 5.43 (t, J = 6.4 Hz, 1H), 4.07 (q,
3
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1
H), 1.42 (s, 3H), 1.09 (t, J = 7.2 Hz, 3H); 13C NMR (100 MHz, CDCl
3
) δ
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2
27.8, 127.7, 127.6, 127.3, 127.2, 126.9, 123.7, 117.9, 60.4, 31.8, 28.6,
+
6.5, 15.5, 12.9; HRMS (ESI) m/z calcd for C30
26
H N
2 4
O Na : 501.1790,
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of 3a (95.7 mg, 0.2 mmol) was added MgI (66.7 mg, 0.24 mmol, 1.2 equiv)
in CH Cl (2 mL) and the solution was stirred for 18 h at room temperature.
The reaction mixture was then diluted with CH Cl (2.0 mL), water (2.0 mL),
and an aqueous solution of NaOH (10 wt%; 1 mL). The aqueous phase
was washed with CH Cl (2 x 5 mL). The combined organic layer was
washed with water (2 x 5 mL), brine (2 x 5 mL), dried over MgSO , and
concentrated under reduced pressure. The residue was purified by flash
chromatography on silica gel (petroleum ether/ethyl acetate = 5:1) to give
the desired compound 5, which was dried under vacuum and further
analyzed by 1H NMR, 13C NMR and high-resolution mass spectrometry.
2
2
2
2
2
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Shen and Y. Tang, Org. Lett. 2010, 12, 504-507.
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nona-1,8-diene-7-carboxylate (5)： yellow oil, 51.7 mg, 54% yield, 82:18
1
dr; H NMR (600 MHz, CDCl
3
) δ (ppm) 7.64 (dd, J = 8.4, 1.2 Hz, 2H), 7.37
–
7.32 (m, 3H), 7.28 – 7.17 (m, 8H), 7.13 – 7.06 (m, 3H), 6.55 (d, J = 2.4
Hz, 1H), 5.03 (dd, J = 6.6, 3.0 Hz, 1H), 4.84 (d, J = 6.6 Hz, 1H), 4.27 –
.22 (m, 2H), 2.20 (s, 3H), 1.33 (t, J = 7.2 Hz, 3H); 13C NMR (150 MHz,
CDCl ) δ (ppm) 195.4, 172.3, 160.7, 140.0, 137.2, 136.9, 133.4, 132.3,
29.0, 128.8, 128.5, 128.0, 126.0, 125.3, 61.9, 54.6, 50.7, 32.0, 29.8, 14.3;
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4
3
1
+
26 2 4
HRMS (ESI) m/z calcd for C30H N O Na : 501.1790, found 501.1789.
Acknowledgements
We are grateful for financial support from the National Natural
Science Foundation of China (81573589, 81630101 and
81773890), the Science & Technology Department of Sichuan
Province (2017JQ0002, 2017TD0001 and 2016TD0006) and the
China Postdoctoral Science Foundation.
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Keywords: Sulfur Ylide • 1,6-Michael Addition •
Vinylcyclopropane • Pyrazolone
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European Journal of Organic Chemistry
10.1002/ejoc.201800710
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This article is protected by copyright. All rights reserved.

European Journal of Organic Chemistry
10.1002/ejoc.201800710
FULL PAPER
FULL PAPER
[
a]
[b]
Xiang Li, Yan-Qing Liu, Jing-Wen
Kang,[ Fei-Yu Chen, Xi-Guo He,
b]
[b]
[a]
[
a]
[b]
Shan-Shan Yuan, Li Guo, Cheng
Peng*[ and Wei Huang*
a,b]
[a]
Page No. – Page No.
A highly diastereoselective cyclopropanation of α,β,γ,δ-unsaturated pyrazolones has
been disclosed. This method allows for construction of a vinylcyclopropane-fused
pyrazolone framework via a 1,6-addition/substitution sequence providing excellent
regio- and chemoselectivity, good yields, broad functional group tolerance and gram-
scale capacity. Moreover, the subsequent transformation of derivatives demonstrates
great potential in building useful synthetic architectures.
Synthesis of Vinylcyclopropane-
Fused Pyrazolone Derivatives via
Sulfur Ylide-Initiated 1,6-Michael
Addition-Cyclization Reactions
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