C–H-Alkenylation of Arenes in a One-Pot VNS – Julia-Kocienski Reaction

Article abstract of DOI:10.1002/ejoc.201801018

A one-pot reaction sequence is reported that enables direct introduction of alkenyl substituents into C–H positions of electron-poor aromatic compounds under transition metal free conditions. The process incorporates vicarious nucleophilic substitution of hydrogen with carbanion of benzotriazolyl chloromethyl sulfone, followed by Julia-Kocienski olefination with aliphatic or aromatic aldehydes or trifluoromethyl ketones. The resulting nitrostyrene derivatives are usually formed with very high E/Z selectivity.

Full text of DOI:10.1002/ejoc.201801018

A Journal of
Accepted Article
Title: C-H-Alkenylation of Arenes in a One-pot VNS - Julia-Kocienski
Reaction
Authors: Rafał Loska
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To be cited as: Eur. J. Org. Chem. 10.1002/ejoc.201801018
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10.1002/ejoc.201801018
European Journal of Organic Chemistry
FULL PAPER
C–H-Alkenylation of Arenes in a One-pot VNS – Julia-Kocienski
Reaction
Rafał Loska*
Abstract: A one-pot reaction sequence is reported that enables
direct introduction of alkenyl substituents into C–H positions of
electron-poor aromatic compounds under transition metal free
conditions. The process incorporates vicarious nucleophilic
substitution of hydrogen with carbanion of benzotriazolyl
chloromethyl sulfone, followed by Julia-Kocienski olefination with
aliphatic or aromatic aldehydes or trifluoromethyl ketones. The
resulting nitrostyrene derivatives are usually formed with very high
E/Z selectivity.
halosubstituted nitrobenzylic carbanions (2, R2 = halogen),
followed by in situ reaction with aldehydes and Michael
acceptors to form nitroaryl oxiranes[8] and cyclopropanes,[9]
respectively, via nucleophilic addition and intramolecular
nucleophilic substitution.
A VNS reaction of a chloromethyl heteroaryl sulfone would result
in the formation of a nitrobenzyl carbanion 2 containing a
heteroaryl sulfonyl group (EWG = HetSO2, Het = heteroaryl) at
the anionic centre. With an appropriate heteroaryl moiety, such
as benzothiazolyl (BT), 2-pyrimidynyl (PY) or phenyltetrazolyl
(PT), such anion would be an appropriate partner for a Julia-
Kocienski (J-K) olefination process,[10] assuming that it is
capable of undergoing addition to a carbonyl compound,
followed by a heterocyclic moiety transfer from sulfur to oxygen
and subsequent SO2 and HetO- elimination. Overall, such a
tandem process would be a means of introducing an alkenyl
moiety into an aromatic ring directly at the position occupied by
hydrogen, in a transition metal-free reaction (Scheme 1(b)). The
HetSO2 moiety would therefore play a dual role: an EWG
enabling deprotonation and carbanion formation necessary for
the VNS step, and elimination of oxygen from the intermediate
aldol adduct in the Julia-type process. Examples of the above
concept exploiting phosphorous chemistry have been already
described in the literature, but they were all two-step processes
and involved preparation of benzylphosphonyl intermediates in a
VNS reaction, followed by condensation with aromatic
aldehydes as a separate step.[11]
Introduction
Development of synthetic methods that enable selective
functionalization of C–H bonds by transforming them into
desired functional groups, without the need for substrate pre-
functionalization, is a prevalent theme of modern organic
synthesis.[1] C–H-alkenylation of aromatic compounds using
alkene substrates that do not contain any activating substituents
began with the Pd-catalysed Fujiwara-Moritani process already
in the 1960s.[2] Discovery of similar, more selective and robust
reaction protocols has been pursued very actively in recent
years, relying mostly upon Rh(III) catalysis and substrates
bearing directing groups in the aromatic ring.[3] Another general
approach to arene C–H-alkenylation is hydroarylation of
alkynes.[4]
Vicarious nucleophilic substitution of hydrogen is
a well-
established and robust method of functionalizing the rings of
electron-deficient arenes, particularly nitroarenes (1).[5] In its
most common, carbon-carbon bond forming variant, the
aromatic ring is attacked by a carbanion stabilised by an
electron-withdrawing group (EWG) and bearing a good leaving
group at the anionic -carbon (Scheme 1(a), X = leaving group).
Consequently, the newly introduced group has the general
structure of an EWG-substituted alkyl. Moderately successful
attempts have been made to perform VNS with EWG groups
(CF3SO2) playing also the role of leaving groups, thus enabling
VNS alkylation of nitroarenes.[6] In recent years, a new approach
to introduce further molecular complexity to the VNS reaction
products has been attracting attention. This concept is based
(a) VNS in nitroarenes
R2
X
R1
R1
R2
EWG
X
+
H
- HX
EWG
O2N
O2N
R2
R2
1
R1
R1
H+
O2N
EWG
EWG
O2N
nitrobenzylic anion (2)
(b) VNS - Julia-Kocienski alkenylation sequence
R2
R2
Cl
R1
R1
R1
R2
KHMDS
BT
BT
S
S
+
Cl
H
O2
O2
-78
C
- HCl
O2S BT
O2N
O2N
O2N
O
1
3
4
R2 = H
R2 = Me
R3
R4
upon reactions of the intermediate nitrobenzylic anions
2
produced in the VNS process with various electrophiles, instead
of simple protonation. Apart from alkylation of such anions,[7]
efficient one-pot processes have been developed that involve
R3
R4
O
R2
R2
R1
R1
R3
C
H alkenylation
products
S
BT
O2
R4
initial VNS reactions with halogenated carbanions to form
-
- BT-O
- SO2
O2N
O2N
[a]
Dr. R. Loska
Institute of Organic Chemistry
Polish Academy of Sciences
Scheme 1. (a) A general scheme of the VNS reaction, (b) one-pot VNS –
Julia-Kocienski olefination of arenes (for clarity, only attack para to NO2 has
been shown).
Kasprzaka 44/52, 01-224 Warsaw, Poland
E-mail: rafal.loska@icho.edu.pl; www.icho.edu.pl
Supporting information for this article is given via a link at the end of
the document.
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10.1002/ejoc.201801018
European Journal of Organic Chemistry
FULL PAPER
(1M in THF) used instead of KHMDS. [c] LiHMDS (0.5M in toluene) used
instead of KHMDS. [d] THF instead of DMF for dissolving 1a and 3.
Herein, successful realization of the one-pot nitroarene
alkenylation is described, using sulfur chemistry and resulting in
the development of a fairly general method of synthesis of both
nitrostyrenes and nitrostilbenes. Such nitroarenes are versatile
synthetic intermediates.[12] In particular, their ortho isomers have
been reported to be very useful as starting materials for the
synthesis of indoles.[13]
With the optimal conditions of the VNS step in hand, attempts
were undertaken to couple this reaction with a J-K-type
alkenylation process by adding carbonyl compounds to the
reaction mixture instead of quenching it with strong acid.
When studying a model reaction between 1a and 3 in the
presence of KHMDS, followed by addition of 4-
chlorobenzaldehyde 5a as a carbonyl reaction partner, it was
Results and Discussion
The development of the VNS – J-K alkenylation methodology
began with investigation of the VNS reaction between
chloromethyl benzothiazolyl sulfone 3 and a simple nitroarene,
4-chloronitrobenzene (1a). The results of the reactions of 1a with
slight excess of 3 (1.2 – 1.4 equiv.) under basic conditions are
summarised in Table 1. Potassium bis(trimethylsilyl) amide
(KHMDS) has been chosen as the base required for VNS, as it
has been reported to be efficient in other VNS reactions
described in the literature[9b,14] and also because it is very
convenient to use as a commercially available 1M solution in
THF. Too short reaction time (Table 1, entry 1) or too low
temperature (entry 3) resulted in poor or moderate yields of the
expected VNS product 3a. Increasing excess of the reagents
and extending the reaction time, while performing it at
intermediate temperature (-30 C, entry 4) gave the highest yield
of 3a (82%). Exchanging the base for a sodium or lithium amide
(NaHMDS, LiHMDS) resulted in lower yield (entry 5), as did
performing the reaction in THF alone instead of DMF (entry 7).
Clearly, the VNS reaction can be efficient only when carbanions
3- do not form tight ion pairs with metal counterions since such
interactions prevent nucleophilic addition of 3- to the aromatic
ring of nitroarene.
quickly established that due to poor nucleophilicity of
-
sulfonylnitrobenzylic carbanions with potassium or sodium
counterions, the equilibrium of their addition to 4-
chlorobenzaldehyde was strongly shifted towards the starting
materials. In consequence, the J-K olefination step failed to
occur at any noticeable rate. Fortunately, this problem could be
averted by addition of excess of lithium salts to the reaction
mixture together with aldehyde after the VNS step, specifically 3
equiv. of LiCl as a 0.5M solution in THF. Larger excess of lithium
salts had little effect on the final yield of nitrostilbene. After
extensive optimization of the tandem process leading from 1a, 3
and 5a to 4-chloro-2-[2-(4-chlorophenyl)ethenyl]nitrobenzene
(6aa)[7a] it was found that the optimal conditions were the
following: 1a (0.5 mmol) and 3 (0.65 mmol) in DMF were added
to KHMDS (1.15 mmol, 1M in THF) at -30 C, then after 40 min
the reaction mixture (deep violet owing to the presence of
carbanions 2) was cooled to -60 C and aldehyde (1.5 mmol)
and LiCl (1.5 mmol, 3 mL of 0.5M THF solution) were slowly
added. The reaction mixture was then allowed to reach slowly
the room temperature. Under these conditions, nitrostilbene 6aa
could be obtained in 65%, as E isomer exclusively. With respect
to the conditions established for the VNS reaction alone, excess
of 3 and of KHMDS had to be diminished slightly to inhibit
formation of side products that result from the J-K reaction
between aldehyde and sulfone 3, leading to chlorostilbenes.[15]
The highest yield of the alkenylation product 6aa obtained after
optimization was still rather moderate, but it has to be noted that
both stages of the reactions are in fact multistep processes.
A two-step alkenylation reaction in the absence of any metal
cations but using DBU as base instead, provided no products of
reaction between 1b, 3 and 5a. Concerning other sulfones
typically used in the J-K olefination processes, 2-pyrimidynyl or
phenyltetrazolyl chloromethyl sulfones gave poor results already
at the VNS step (low conversion and formation of unidentified
numerous side products). Another approach to VNS-based
alkenylation of arenes has also been attempted which was
based upon an innovative sulfone-based olefination protocol
developed recently by the Barbasiewicz group.[16] Unlike the J-K
and similar olefination reactions, this reaction is based upon
addition of deprotonated sulfonyl esters to carbonyl compounds,
followed by sulfaoxetane formation in a manner resembling the
mechanism of the Wittig reaction. A VNS reaction between o-
chloronitrobenzene and appropriate sulfonyl ester (2,2,2-
trifluoroethyl chloromethanesulfonate) could be achieved but,
unfortunately, the intermediate nitrobenzylsulfonyl anion failed to
Table 1. Optimization of the VNS reaction between 4-chloronitrobenzene 1a
and chloromethyl sulfone 3 (BT = 2-benzothiazolyl)[a]
1) KHMDS
Cl
H
Cl
BT
2) HCl
S
+
BT
3a
O2
NO2
Cl
S
O2N
O2
1a
3
Amount of 3
(mmol)
Amount of base
(mmol)
Time,
temperature
3a isolated
yield
1
0.6
1.25
1.25
1.25
1.4
15 min, -20 C
30 min, -45 C
30 min, -78 C
52%
2
3
4
5
6
7
0.6
55%
0.6
<20%
82%
57%
0.75
0.75
0.75
0.6
45 min, -30 C
1.4[b]
1.4[c]
1.25
45 min, -30 C
45 min, -30 C
45 min, -30 C
<5%
<5%[d]
[a] To KHMDS (1M in THF) a solution of 1a (0.5 mmol).and 3 in DMF (the
same volume as KHMDS solution) was added dropwise under inert
atmosphere and quenched with 2M HCl after time indicated. [b] NaHMDS
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10.1002/ejoc.201801018
European Journal of Organic Chemistry
FULL PAPER
react further with aldehydes even in the presence of lithium salts, requirements of carbanion 3- are moderate, unlike some other
probably due to its low nucleophilicity.
nucleophiles employed in one-pot processes involving VNS, for
example PhCCl2-.[9b] A serious limitation of those processes was
inability to achieve efficient substitution ortho to the nitro group.
Nitroarenes with more than one C–H position activated for
nucleophilic attack give mixtures of regioisomers. For example,
3-iodonitrobenzene reacted at the para and the less hindered
ortho position, in both cases with complete E selectivity.
Interestingly, with nitroarenes substituted ortho to NO2 with Cl or
OMe the reaction proceeded with lower E/Z selectivity, usually
with marked preference for Z isomers (7b, 7k, 7m). Moreover,
this effect occurred only for alkenylation ortho to the nitro group,
as product 7b’ was obtained as E isomer only (Scheme 3, top).
The crucial role of Li+ cations for the one-pot alkenylation
protocol can be probably explained by their coordination to the
intermediate carbanions of the type 2 (EWG = BTSO2) and
exchange of K+ counterions, accompanied by Lewis-acidic
activation of the aldehyde carbonyl group and facilitating the
nucleophilic addition step. Moreover, the Li+ cation probably
stabilizes the aldol adduct and thus enables the BT moiety
transfer and further elimination. The whole one-pot protocol
cannot be simplified by using a lithium base at the VNS step
since lithiated carbanions of sulfones fail to attack nitroarene
rings.
NO2
NO2
R
Et
Cl
(i)
Cl
Et
Cl
Et
1a
3
+
+
7a R = Cl (68%)
7c R = CF3 (63%)[a]
7d R = CN (56%)[b]
7f R = F (41%)
NO2
O2N
R
R = 4-Cl 6aa (65%)
7b (28%; Z:E 3.7:1)
7b' (38%)
R = 4-OMe 6ab (21%)
R = 2-F,3-F 6ac (68%)
R = 4-CF3 6ad (59%)
NO2
NO2
O2N
R
Et
NO2
Et
I
NO2
Et
+
Cl
NO2
Cl
Ar
(i)
Cl
Ar
Et
3
+
+
7j R = Cl
I
Cl
O2N
(27%; Z:E 1:1.7)[a]
7k R = OMe
SO2
N
7g' (48%)
7g (24%)
6ba (34%)
6ba' (32%)
1b
O
7e (64%)
(43%; Z:E 2.7:1)
Et
Et
Scheme 2. Synthesis of nitrostilbenes in a one-pot VNS-J-K olefination
reaction. (i) 1) KHMDS, 2) aldehyde 5a-d, LiCl
OMe
NO2
NO2
NO2
N
Et
N
7m
NO2
7l (63%)[a]
The optimized synthetic procedure has been next applied to the
synthesis of nitrostilbenes. As demonstrated by the examples
shown in Scheme 2, the reaction proceeds with both electron-
poor and electron-rich benzaldehydes: 4-methoxy (5b), 2,3-
difluoro (5c) and 4-trifluoromethyl (5d). The yield of the reaction
with 5b was lower, though, probably due to its lower
electrophilicity resulting in less efficient reaction with the
nitrobenzylic carbanions 2. 2-Chloronitrobenzene, which
displays two non-equivalent positions activated by the nitro
group, gave two isomeric products 6ba, 6ba’ in nearly equal
amounts.
7i (35%)[c]
7h (56%)[c]
(19%; Z:E 2.9:1)[a]
Et
[a]
Scheme 3. Alkenylation of nitroarenes and nitroheterocycles. VNS time: 15
min. [b] VNS time: 5 min. [c] VNS time: 10 min.
The yields of alkenylation obtained for some strongly
electrophilic arenes are moderate (7d, j, h, m), although such
substrates should be excellent partners for nucleophilic attack. It
seems that high electrophilicity of the aromatic ring associated
with good delocalisation of negative charge results in low
nucleophilicity of the intermediate benzotriazolylsulfonyl
nitrobenzyl anions 2, which results in less efficient addition to
aldehyde and overall lower yield of the two-step process. For
these reasons alkenylation of 3-nitropyridine or nitropyrrole and
nitrothiazole derivatives failed altogether, although nucleophilic
addition of 3- evidently proceeded well, as evidenced by strong
coloration of the reaction mixtures. On the other hand, a
minimum electrophilic character of the starting arene is required,
as nitroanisoles fail to react with 3- carbanion. The presence of
additional weakly activating substituents such as Cl is already
sufficient for the VNS of o-nitroanisole to proceed (7k formed in
43% yield).
Interestingly, the alkenylation process turned out to be efficient
also with aliphatic, enolizable aldehydes, which generally tend to
be problematic in reactions performed under basic conditions.
Under the same conditions as those established above for
aromatic aldehydes, propionaldehyde provided a series of
ethylvinyl derivatives of various nitroarenes in moderate or good
yields (Scheme 3). These reactions were also much cleaner
than those of benzaldehydes. Only traces of side products
formed in Knoevenagel-like condensation of propanal with
sulfone 3 were detected in some cases, whereas excess of
propanal and its J-K olefination product (1-chlorobutene) were
easily removed during evaporation. Nitroarenes with para
position blocked with substituents such as Cl, afforded products
of ortho substitution exclusively in E configuration, in moderate
Generally, nucleophilic attack is strongly preferred at ring
positions activated by NO2 and occupied by hydrogen atoms.[5]
Accordingly, alkenylation of 4-fluoronitrobenzene proceeded
selectively ortho to the nitro group to give nitrostyrene 7f. On the
other hand, with increasing electrophility of the ring classical
1
to good yields. No Z isomers could be detected by H NMR of
crude reaction mixtures nor by TLC analysis. Efficient
substitution ortho to the NO2 group indicates that the sterical
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10.1002/ejoc.201801018
European Journal of Organic Chemistry
FULL PAPER
SNAr substitution of fluorine becomes predominant as observed
in the reaction of ethyl 4-fluoro-3-nitrobenzoate, which resulted
in an inseparable mixture of product of H and F substitution in
very low yield.
A benzothiazolyl sulfone bearing a branched chloroalkyl chain
should in principle provide nitroaryl alkenes with higher degree
of substitution at the double bond. Indeed, the reaction of
sulfone 4 with 1b and propanal gave alkenes E,Z-8b, but in low
yield probably due to higher steric hindrance as compared to the
standard reagent 3 (Scheme 4).
group from the plane of the aromatic ring in aldol-type adducts
formed from nitrobenzylic carbanions
2
and carbonyl
compounds. If one of the NO2 oxygen atoms participates in
coordination of Li+ cation together with the anionic aldol oxygen,
than the abovementioned deviation from planarity can certainly
influence the energy of diastereoselective aldol adducts and/or
of the transition states that lead to them. That in turn affects the
ratio of Z and E isomers of the final alkene.
Conclusions
Me
Cl
SO2
1) KHMDS
2) EtCHO, LiCl
Cl
Me
N
S
Me
1b
+
A one-pot VNS – Julia-Kocienski reaction sequence has been
developed that allows for direct substitution of hydrogen of an
electron-deficient aromatic ring with an alkenyl group, often with
high E selectivity. Importantly, although the reaction involves
basic conditions, it tolerates simple, enolizable aliphatic
aldehydes that lead to alkylvinyl products. Ketones are generally
O2N
8b (13%, E:Z 3:1)
4
Scheme 4. Synthesis of a trisubstituted alkene from sulfone 4
poor
substrates,
but
trifluoromethylketones
provide
Simple enolizable ketones such as acetone fail to give
alkenylation products, obviously due to concurrent enolisation
and lower electrophilic character compared to aldehydes.
However, more electrophilic trifluoromethyl phenyl ketone turned
out to be a viable substrate, providing a method of synthesis of
trifluoromethylalkenes efficiently. Both homo- and heterocyclic
aromatic nitro compounds can be thus transformed selectively
into nitrostyrenes containing alkyl, aryl and trifluoromethyl
substituents. The success of this two-step transformation
depends upon meeting the specific requirements of the both
reactions regarding the kind of metal cations present in the
reaction mixture.
trifluoromethylvinyl-substituted
nitroarenes.[17]
Another
electrophilic ketone capable of reacting with nitrobenzylic anions
2 was N-methylisatin which yielded the expected alkene 10 as a
single stereoisomer, but in low yield (Scheme 5).
1) KHMDS
2) PhCOCF3,
LiCl
Experimental Section
R
CF3
Ph
Ph
+
1
3
Compound 3a: In a flame-dried Schlenk flask filled with argon a 1M THF
solution of KHMDS (1.4 mmol, 1.4 mL) was placed and cooled to -30 C.
A solution of nitroarene (0.5 mmol) and sulfone 3 (0.75 mmol, 186 mg) in
DMF (1.4 mL) was added dropwise with vigorous stirring. The stirring
continued at -30 C for 45 min and 2M HCl(aq) (0.75 mL) was then added,
followed by brine (5 mL), water (2 mL) and Et2O (5 mL). The mixture was
then separated between Et2O (25 mL) and brine (50 mL), the organic
phase was washed with brine (3 x 40 mL), dried over anhydrous Na2SO4
and concentrated. Purification by column chromatography on silica gel
using hexanes–AcOEt 2:1 gave 3a as yellow solid in 152 mg (82%) yield.
Crystallisation from heptane–CH2Cl2 gave yellow crystals. M.p. 146–148
C . 1H NMR (500 MHz, CDCl3): = 5.35 (s, 2H, CH2), 7.52 (m, 2H,
O2N
F3C
NO2
Cl
Ph
Cl
Ph
+
CF3
CF3
O2N
N
NO2
9l (58%)
9b
(34%; Z:E 1.3:1)
9b' (8%)
Cl
Me
N
O
1) KHMDS
2) LiCl,
+
1a
3
O
3
3
NO2
10 (13%)
Harom), 7.62 (t, JH,H = 7.14 Hz, 1H, Harom), 7.67 (t, JH,H = 7.14 Hz, 1H,
O
3
3
Harom), 8.00 (d, JH,H = 8.4 Hz, 1H, Harom), 8.03 (d, JH,H = 8.4 Hz, 1H,
N
Me
3
Harom), 8.22 (d, JH,H = 7.9 Hz, 1H, Harom) ppm. 13C NMR (125 MHz,
CDCl3): = 56.8, 122.3, 123.8, 125.6, 127.2, 127.9, 128.4, 130.6, 134.3,
136.8, 139.9, 147.7, 152.4, 164.5 ppm. HRMS (ESI+) calcd for
C14H10ClN2O4S2 ([M+H]+), 368.9771; found, 368.9775.
Scheme 5. Synthesis of trisubstituted alkenes from ketones
General procedure for alkenylation of nitroarenes. In a flame-dried
Schlenk flask filled with argon a 1M THF solution of KHMDS (1.15 mmol,
1.15 mL) was placed and cooled to -30 C. A solution of nitroarene (0.5
mmol) and sulfone 3 (0.65 mmol, 161 mg) in DMF (1.15 mL) was added
dropwise with vigorous stirring. The stirring continued at -30 C for 40
min (or, for some substrates, shorter time period indicated in Scheme 3).
The reaction mixture was then cooled to -60 C and benzaldehyde
derivative (1.5 mmol), ketone (1.5 mmol) or propanal (2.0 mmol, 116 mg,
144 L) was added dropwise, followed by LiCl (1.5 mmol, 3.0 mL of 0.5M
From the examples of olefination with both aldehydes and
ketones described above it is evident that loss of
stereoselectivity in the newly formed double bond occurs only
when the nitro group becomes flanked by two substituents at its
ortho, ortho’ positions (7b, 7j, 7k, 7m, 9b), with one exception of
stilbene 6ba. An extensive computational study is probably
necessary to explain this phenomenon, but it is reasonable to
assume that it may result from a significant deviation of the NO2
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10.1002/ejoc.201801018
European Journal of Organic Chemistry
FULL PAPER
THF solution). The reaction was allowed to warm to RT and stirred for
another 20 h. 2M HCl(aq) (0.75 mL) was then added, followed by brine (5
mL), water (2 mL) and Et2O (5 mL). For amine products (7m, 7n), the
water phase was neutralized at this point by dilution with saturated
aqueous Na2CO3 (2 mL) and addition of solid Na2CO3. The mixture was
then separated between Et2O (25 mL) and brine (50 mL), the organic
phase was washed with brine (3 x 40 mL), dried over anhydrous Na2SO4
and concentrated. The products were purified by column chromatography
on silica gel using hexanes, hexanes–CH2Cl2 5:1 or hexanes–Et2O 10:1
as eluent.
(d, 3JH,H = 16.1 Hz, 1H, vinyl CH), 7.34 (d, 3JH,H = 8.5 Hz, 2H, Harom), 7.41
(m, 4H, Harom), 7.65 (m, 1H, Harom) ppm. 13C NMR (100 MHz, CDCl3):
=
120.2, 124.7, 125.4, 128.3, 129.1, 129.2, 130.7, 131.2, 133.9, 134.2,
134.9, 148.4 ppm.
(E)-2-Chloro-4-[2-(4-chlorophenyl)ethenyl]nitrobenzene (6ba’): 49 mg
(32%) yield, yellow crystals (heptane–CH2Cl2). M.p. 152–154 C. 1H
NMR (400 MHz, CDCl3): = 7.01 (d, 3JH,H = 16.3 Hz, 1H, vinyl CH), 7.17
(d, 3JH,H = 16.3 Hz, 1H, vinyl CH), 7.37 (d, 3JH,H = 8.4 Hz, 2H, Harom), 7.47
(m, 3H, Harom), 7.63 (s, 1H, Harom), 7.93 (d, 3JH,H = 8.5 Hz, 1H, Harom) ppm.
13C NMR (100 MHz, CDCl3): = 125.0, 125.6, 126.4, 128.0, 128.2, 129.2,
129.4, 132.7, 134.4, 134.8, 142.7, 146.1 ppm. MS (EI): m/z (%) = 293
(M+, 100), 263 (25), 212 (83), 176 (73), 165 (41). HRMS (EI) calcd for
C14H9Cl2NO2 (M+), 293.0010; found, 293.0009.
(E)-4-Chloro-2-[2-(4-chlorophenyl)ethenyl]nitrobenzene (6aa):[7a] 96
1
mg (65%) yield, yellow crystals (heptane–CH2Cl2). M.p. 105–107 C . H
NMR (400 MHz, CDCl3): = 7.03 (d, 3JH,H = 16.1 Hz, 1H, vinyl CH), 7.37
(m, 3H, Harom), 7.47 (d, 3JH,H = 8.5 Hz, 2H, Harom), 7.56 (d, 3JH,H = 16.1 Hz,
4
3
1H, vinyl CH), 7.71 (d, JH,H = 2.2 Hz, 1H, Harom), 7.96 (d, JH,H = 8.7 Hz,
(E)-2-(But-1-enyl)-4-chloronitrobenzene (7a): 72 mg (68%) yield, pale
1H, Harom) ppm.
yellow oil. IR (CH2Cl2): max = 3099, 2968, 2932, 2875, 1600, 1563, 1522,
1
1461, 1343, 964, 909, 841 cm-1. H NMR (400 MHz, CDCl3): = 1.11 (t,
(E)-4-Chloro-2-[2-(4-methoxyphenyl)ethenyl]nitrobenzene (6ab): 30
mg (21%) yield, yellow crystals (heptane–CH2Cl2). M.p. 78–79 C. IR
3JH,H = 7.5 Hz, 3H, CH3), 2.28 (m, 2H, CH2), 6.29 (dt, 3JH,H = 15.6 Hz, 6.5
3
3
Hz, 1H, vinyl CH), 6.82 (d, JH,H = 15.7 Hz, 1H, vinyl CH), 7.27 (dd, JH,H
4
4
(KBr):
= 3062, 2957, 2932, 2835, 1596, 1508, 1459, 1342, 1298,
= 8.7 Hz, JH,H = 2.2 Hz, 1H, Harom), 7.54 (d, JH,H = 2.2 Hz, 1H, Harom),
max
1251, 1173, 1025, 921, 811 cm-1. 1H NMR (400 MHz, CDCl3): = 3.84 (s,
7.83 (d, JH,H = 8.7 Hz, 1H, Harom) ppm. 13C NMR (100 MHz, CDCl3):
=
3
3
3
3H, OCH3), 6.92 (d, JH,H = 8.7 Hz, 2H, Harom), 7.06 (d, JH,H = 16.1 Hz,
1H, vinyl CH), 7.31 (dd, 3JH,H = 8.8 Hz, 4JH,H = 2.2 Hz, 1H, Harom), 7.47 (m,
vinyl CH, 3H, Harom), 7.72 (d, JH,H = 2.2 Hz, 1H, Harom), 7.92 (d, JH,H
8.7 Hz, 1H, Harom) ppm. 13C NMR (100 MHz, CDCl3): = 55.4, 114.3,
120.0, 126.4, 127.4, 127.6, 128.7, 128.9, 134.8, 135.2, 139.4, 145.9,
160.4 ppm. MS (EI): m/z (%) = 289 (M+, 56), 272 (54), 244 (39), 199 (32),
165 (58), 153 (63), 135 (100), 121 (77). HRMS (EI) calcd for
C15H12ClNO3 (M+), 289.0506; found, 289.0492.
13.1, 26.2, 123.2, 125.9, 127.3, 128.2, 135.3, 139.1, 139.7, 145.8 ppm.
MS (EI): m/z (%) = 211 (M+, 10), 194 (23), 182 (15), 166 (35), 154 (43),
138 (25), 126 (63), 115 (52), 99 (38), 75 (50), 57 (100). HRMS (EI) calcd
for C10H10ClNO2 (M+), 211.0400; found, 211.0402. Anal. calcd for
C10H10ClNO2: C, 56.75; H, 4.76; N, 6.62; Cl, 16.75. Found: C, 56.97; H,
4.70; N, 6.53; Cl, 16.55.
4
3
=
(E,Z)-2-(But-1-enyl)-6-chloronitrobenzene (7b): 30 mg (28%) yield, Z:E
3.7:1; pale yellow oil. IR (CH2Cl2):
= 2969, 2876, 1538, 1461, 1367,
max
(E)-4-Chloro-2-[2-(2,3-difluorophenyl)ethenyl]nitrobenzene
(6ac):
1187, 851, 790, 715 cm-1. Z: 1H NMR (400 MHz, CDCl3): = 1.00 (t, 3JH,H
3
100 mg (68%) yield, pale yellow crystals, (heptane–CH2Cl2). M.p. 116–
118 C. IR (KBr): max = 3077, 1921, 1594, 1563, 1509, 1481, 1335, 1285,
1252, 1197, 1068, 983, 921, 848, 780, 715 cm-1. 1H NMR (400 MHz,
= 7.5 Hz, 3H, CH3), 2.13 (m, 2H, CH2), 5.88 (dt, JH,H = 11.4 Hz, 7.5 Hz,
1H, vinyl CH), 6.22 (m, 1H, vinyl CH), 7.24 (m, 1H, Harom), 7.37 (m, 2H,
Harom) ppm. E:1H NMR (400 MHz, CDCl3): = 1.07 (t, 3JH,H = 7.4 Hz, 3H,
CH3), 2.24 (m, 2H, CH2), 6.22 (m, 1H, vinyl CH), 6.38 (dt, 3JH,H = 15.7 Hz,
6.4 Hz, 1H, vinyl CH), 7.33 (m, 2H, Harom), 7.47 (m, 1H, Harom) ppm. E,Z:
13C NMR (100 MHz, CDCl3): = 13.0, 13.9, 22.1, 26.2, 120.5, 120.7,
124.8, 124.9, 124.9, 127.9, 128.3, 128.7, 128.8, 130.2, 130.5, 131.8,
132.0, 140.0, 140.3. MS (EI): m/z (%) = 211 (M+, 2), 194 (27), 179 (12),
166 (41), 154 (63), 125 (73), 115 (61), 90 (75), 75 (64), 57 (100). HRMS
(EI) calcd for C10H10ClNO2 (M+), 211.0400; found, 211.0397.
3
CDCl3): = 7.11 (m, 2H, Harom), 7.19 (d, JH,H = 16.2 Hz, 1H, vinyl CH),
3
4
7.37 (m, 1H, Harom), 7.40 (dd, JH,H = 8.7 Hz, JH,H = 2.2 Hz, 1H, Harom),
7.66 (d, 3JH,H = 16.2 Hz, 1H, vinyl CH), 7.72 (d, 4JH,H = 2.2 Hz, 1H, Harom),
7.96 (d, JH,H = 8.7 Hz, 1H, Harom) ppm. 13C NMR (50 MHz, CDCl3):
3
=
117.0, 117.3, 122.2 (m), 124.2 (dd, JC,F = 6.9 Hz, 4.6 Hz), 125.9 (m),
1
126.2 (m), 126.4, 128.3, 128.5, 134.5, 139.8, 146.0, 148.6 (dd, JC,F
=
2
1
2
252.5 Hz, JC,F = 13.4 Hz), 150.9 (dd, JC,F = 248.0 Hz, JC,F = 12.6 Hz)
ppm. 19F NMR (376 MHz, CDCl3): = -142.66 (1F, dm, 3JF,F = 20.2 Hz), -
137.90 (1F, dm, JF,F = 19.4 Hz) ppm. MS (EI): m/z (%) = 295 (M+, 26),
3
(E)-4-(But-1-enyl)-2-chloronitrobenzene (7b’): 40 mg (38%) yield, pale
278 (44), 250 (30), 212 (48), 201 (47), 153 (100), 141 (69), 127 (89).
HRMS (EI) calcd for C14H8F2ClNO2 (M+), 295.0212; found, 295.0206.
yellow oil. IR (CH2Cl2): max = 2968, 2933, 2875, 1650, 1590, 1523, 1345,
1
3
1046, 966, 837 cm-1. H NMR (400 MHz, CDCl3): = 1.11 (t, JH,H = 7.4
Hz, 3H, CH3), 2.28 (m, 2H, CH2), 6.34 (d, 3JH,H = 15.9 Hz, 1H, vinyl CH),
3
3
(E)-4-Chloro-2-[2-(4-trifluoromethylphenyl)ethenyl]nitrobenzene
(6ad): 96 mg (59%) yield, pale yellow crystals, (heptane–CH2Cl2). M.p.
139–140 C. IR (KBr): max = 3079, 1563, 1519, 1328, 1159, 1113, 1068,
966, 864, 817 cm-1. 1H NMR (400 MHz, CDCl3): = 7.08 (d, 3JH,H = 16.1
6.46 (dt, JH,H = 15.8 Hz, 6.3 Hz, 1H, vinyl CH), 7.31 (dd, JH,H = 8.7 Hz,
4JH,H = 1.8 Hz, 1H, Harom), 7.47 (d, 4JH,H = 1.8 Hz, 1H, Harom), 7.86 (d, 3JH,H
= 8.5 Hz, 1H, Harom) ppm. 13C NMR (100 MHz, CDCl3): = 13.1, 26.2,
124.5, 126.0, 126.2, 127.7, 128.9, 138.8, 143.7, 145.6 ppm.
3
4
Hz, 1H, vinyl CH), 7.40 (dd, JH,H = 8.8 Hz, JH,H = 2.0 Hz, 1H, Harom),
7.65 (m, vinyl CH, 5H, Harom), 7.72 (d, 4JH,H = 2.0 Hz, 1H, Harom), 7.98 (d,
3JH,H = 8.7 Hz, 1H, Harom) ppm. 13C NMR (100 MHz, CDCl3): = 124.0 (q,
(E)-2-(But-1-enyl)-1-nitro-4-trifluoromethylbenzene (7c): 77 mg (63%)
yield, colourless oil. IR (film): max = 2971, 2878, 1532, 1328, 1176, 1137,
3
1JC,F = 272.1 Hz), 125.2, 125.8 (q, JC,F = 3.8 Hz), 126.5, 127.3, 128.2,
1096, 965, 916, 843 cm-1. 1H NMR (400 MHz, CDCl3): = 1.13 (t, 3JH,H
=
2
128.5, 130.6 (q, JC,F = 32.4 Hz), 133.3, 134.4, 139.4, 139.8, 146.1. 19F
7.4 Hz, 3H, CH3), 2.32 (m, 2H, CH2), 6.39 (dt, 3JH,H = 15.7 Hz, 6.5 Hz, 1H,
vinyl CH), 6.80 (dt, 3JH,H = 15.7 Hz, 4JH,H = 1.5 Hz, 1H, vinyl CH), 7.58 (dd,
NMR (376 MHz, CDCl3): = -62.68 (s, CF3) ppm. MS (EI): m/z (%) = 327
(M+, 18), 310 (47), 282 (30), 246 (22), 225 (24), 176 (46), 173 (51), 159
(52), 153 (100), 125 (81). HRMS (EI) calcd for C15H9F3ClNO2 (M+),
327.0274; found, 327.0262.
4
4
3JH,H = 8.5 Hz, JH,H = 1.7 Hz, 1H, Harom), 7.84 (d, JH,H = 1.1 Hz, 1H,
3
Harom), 7.93 (d, JH,H = 8.5 Hz, 1H, Harom) ppm. 13C NMR (100 MHz,
1
3
CDCl3): = 13.0, 26.3, 122.6, 123.0 (q, JC,F = 272.8 Hz), 124.1 (q, JC,F
3
2
= 3.5 Hz), 124.9, 125.5 (q, JC,F = 3.6 Hz), 133.9, 134.3 (q, JC,F = 33.3
Hz), 140.5, 149.5 ppm. 19F NMR (376 MHz, CDCl3): = -63.26 (s, CF3)
ppm. MS (EI): m/z (%) = 245 (M+, 3), 228 (13), 200 (22), 188 (30), 160
(E)-2-Chloro-6-[2-(4-chlorophenyl)ethenyl]nitrobenzene (6ba): 50 mg
(34%) yield, colourless crystals (heptane–CH2Cl2). M.p. 113–114 C. 1H
NMR (400 MHz, CDCl3): = 6.86 (d, 3JH,H = 16.0 Hz, 1H, vinyl CH), 7.12
This article is protected by copyright. All rights reserved.

10.1002/ejoc.201801018
European Journal of Organic Chemistry
FULL PAPER
(40), 57 (100). HRMS (EI) calcd for C11H10F3NO2 (M+), 245.0664; found,
245.0664.
(E)-4-(But-1-enyl)-1-nitronaphthalene (7h): 64 mg (56%) yield, pale
yellow oil. IR (CH2Cl2): max = 3064, 2965, 2874, 1648, 1524, 1459, 1362,
1
3
960, 865, 813, 747 cm-1. H NMR (400 MHz, CDCl3): = 1.12 (t, JH,H
=
3
7.5 Hz, 3H, CH3), 2.30 (m, 2H, CH2), 6.47 (d, JH,H = 15.9 Hz, 1H, vinyl
CH), 6.53 (dt, 3JH,H = 15.8 Hz, 5.4 Hz, 1H, vinyl CH), 7.51 (m, 1H, Harom),
7.58 (m, 1H, Harom), 7.67 (t, 3JH,H = 8.0 Hz, 2H, Harom), 7.84 (t, 3JH,H = 8.0
Hz, 2H, Harom) ppm. 13C NMR (100 MHz, CDCl3): = 13.2, 26.5, 121.6,
121.7, 122.9, 124.7, 126.9, 126.9, 127.9, 128.6, 130.2, 132.6, 139.5,
146.0 ppm. MS (EI): m/z (%) = 227 (M+, 36), 210 (78), 182 (44), 170
(100), 165 (81), 141 (83), 127 (67), 115 (86), 57 (71). HRMS (EI) calcd
for C14H13NO2 (M+), 227.0946; found, 227.0947. Anal. calcd for
C14H13NO2: C, 73.99; H, 5.77; N, 6.16. Found: C, 73.74; H, 5.71; N, 6.13.
(E)-2-(But-1-enyl)-4-cyanonitrobenzene (7d): 57 mg (56%) yield, white
needles (heptane–CH2Cl2). M.p. 86–88 C. IR (KBr):
= 3077, 2970,
max
2882, 2231, 1649, 1573, 1518, 1362, 1267, 962, 901, 830, 736, 611 cm-1.
1H NMR (400 MHz, CDCl3): = 1.13 (t, 3JH,H = 7.4 Hz, 3H, CH3), 2.31 (m,
2H, CH2), 6.38 (dt, 3JH,H = 15.7 Hz, 6.5 Hz, 1H, vinyl CH), 6.74 (d, 3JH,H
=
15.7 Hz, 1H, vinyl CH), 7.61 (dd, 3JH,H = 8.4 Hz, 4JH,H = 1.7 Hz, 1H, Harom),
7.89 (d, 4JH,H = 1.6 Hz, 1H, Harom), 7.91 (d, 3JH,H = 8.4 Hz, 1H, Harom) ppm.
13C NMR (100 MHz, CDCl3): = 12.9, 26.3, 116.6, 116.9, 121.9, 125.1,
130.4, 132.4, 134.3, 141.3, 149.6 ppm. MS (EI): m/z (%) = 202 (M+, 6),
185 (17), 157 (47), 145 (46), 117 (74), 57 (100). HRMS (EI) calcd for
C11H10N2O2 (M+), 202.0742; found, 202.0736. Anal. calcd for C11H10N2O2:
C, 65.34; H, 4.98; N, 13.85. Found: C, 65.23; H, 5.05; N, 13.69.
(E)-1-(But-1-enyl)-2-nitronaphthalene (7i): 40 mg (35%) yield, pale
yellow oil. IR (CH2Cl2):
= 2965, 2930, 2873, 1587, 1524, 1345, 967,
max
819, 760 cm-1. 1H NMR (400 MHz, CDCl3): = 1.18 (t, 3JH,H = 7.5 Hz, 3H,
CH3), 2.37 (m, 2H, CH2), 5.91 (dt, 3JH,H = 16.1 Hz, 6.4 Hz, 1H, vinyl CH),
Sulfonamide 7e: 104 mg (64%) yield, pale yellow crystals (heptane–
3
4
CH2Cl2). M.p. 107–108 C. 1H NMR (500 MHz, CDCl3): = 1.14 (t, 3JH,H
=
6.86 (dt, JH,H = 16.1 Hz, JH,H = 1.6 Hz, 1H, vinyl CH), 7.61 (m, 2H,
3
3
Harom), 7.81 (d, JH,H = 9.0 Hz, 1H, Harom), 7.84 (d, JH,H = 9.0 Hz, 1H,
Harom), 7.89 (m, 1H, Harom), 8.27 (m, 1H, Harom) ppm. 13C NMR (100 MHz,
CDCl3): = 13.1, 26.4, 120.0, 121.4, 127.4, 127.8, 128.0, 128.2, 128.4,
132.0, 132.4, 134.8, 140.8, 146.2 ppm. MS (EI): m/z (%) = 227 (M+, 53),
210 (70), 198 (45), 170 (100), 143 (70), 115 (100), 57 (76). HRMS (EI)
calcd for C14H13NO2 (M+), 227.0946; found, 227.0941.
7.4 Hz, 3H, CH3), 2.33 (m, 2H, CH2), 3.07 (m, 4H, NCH2), 3.77 (m, 4H,
3
3
OCH2), 6.43 (dt, JH,H = 15.8 Hz, 6.4 Hz, 1H, vinyl CH), 6.78 (d, JH,H
=
15.5 Hz, 1H, vinyl CH), 7.69 (dd, 3JH,H = 8.4 Hz, 4JH,H = 2.0 Hz, 1H, Harom),
7.95 (d, 4JH,H = 1.8 Hz, 1H, Harom), 7.97 (d, 3JH,H = 8.4 Hz, 1H, Harom) ppm.
13C NMR (125 MHz, CDCl3): = 12.9, 26.3, 45.9, 66.0, 122.2, 125.2,
126.1, 127.6, 134.3, 139.3, 141.2, 149.8 ppm. MS (EI): m/z (%) = 151
(100), 123 (58), 96 (60).
(E,Z)-1-(But-1-enyl)-3,5-dichloro-2-nitrobenzene (7j): 34 mg (27%)
yield. pale yellow oil, Z:E 1:1.7. IR (CH2Cl2):
= 3078, 2969, 2934,
max
(E)-2-(But-1-enyl)-4-fluoronitrobenzene (7f): 40 mg (41%) yield, pale
yellow oil. IR (CH2Cl2): max = 3083, 2969, 2876, 1617, 1580, 1524, 1471,
1347, 1273, 1219, 1075, 964, 877, 843, 752, 607 cm-1. 1H NMR (400
MHz, CDCl3): = 1.12 (t, 7.5 Hz, 3H, CH3), 2.30 (m, 2H, CH2), 6.29 (dt,
15.6 Hz, 6.5 Hz, 1H, vinyl CH), 6.88 (dm, 15.6 Hz, 1H, vinyl CH), 7.01
2875, 1540, 1363, 1135, 962, 861 cm-1. Z: H NMR (400 MHz, CDCl3):
1
3
3
= 1.02 (t, JH,H = 7.5 Hz, 3H, CH3), 2.14 (m, 2H, CH2), 5.92 (dt, JH,H
=
=
4
11.5 Hz, 7.5 Hz, 1H, vinyl CH), 6.17 (m, 1H, vinyl CH), 7.22 (d, JH,H
4
2.0 Hz, 1H, Harom), 7.40 (d, JH,H = 2.0 Hz, 1H, Harom) ppm. E: 1H NMR
3
3
3
(ddd, JH,H = 9.2 Hz, JH,F = 7.3 Hz, 4JH,H = 2.8 Hz, 1H, Harom), 7.25 (3JH,F
(400 MHz, CDCl3): = 1.07 (t, JH,H = 7.5 Hz, 3H, CH3), 2.25 (m, 2H,
3
4
3
4
CH2), 6.17 (m, 1H, vinyl CH), 6.40 (dt, JH,H = 15.6 Hz, 6.5 Hz, 1H, vinyl
= 9.6 Hz, JH,H = 2.8 Hz, 1H, Harom), 7.96 (dd, JH,H = 9.1 Hz, JH,F = 5.2
CH), 7.33 (d, 4JH,H = 2.0 Hz, 1H, Harom), 7.45 (d, 4JH,H = 2.0 Hz, 1H, Harom
)
Hz, 1H, Harom) ppm. 13C NMR (100 MHz, CDCl3): = 13.0, 26.2, 114.4 (d,
ppm. Z, E: 13C NMR (100 MHz, CDCl3): = 12.9, 13.8, 22.1, 26.3, 119.7,
119.9, 125.0, 126.06, 126.07, 128.0, 128.5, 128.8, 133.1, 133.2, 135.9,
136.2, 141.3, 141.4 ppm. MS (EI): m/z (%) = 245 (M+, 3), 228 (17), 200
(30), 188 (44), 159 (72), 124 (56), 57 (100). HRMS (EI) calcd for
C10H9Cl2NO2 (M+), 245.0010; found, 245.0018.
2JC,F = 23.7 Hz), 114.8 (d, JC,F = 24.1 Hz), 123.6, 127.3 (d, JC,F = 9.9
2
3
Hz), 136.9 (d, 3JC,F = 9.5 Hz), 139.6, 164.6 (d, 1JC,F = 255.1 Hz) ppm. 19
F
NMR (376 MHz, CDCl3): = -104.75 (m) ppm. MS (EI): m/z (%) = 195
(M+, 9) 178 (14), 150 (25), 138 (27), 133 (30), 109 (40), 83 (35), 75 (36),
57 (100). HRMS (EI) calcd for C10H10FNO2 (M+), 195.0696; found,
195.0698.
(E)-2-(But-1-enyl)-4-chloro-6-methoxynitrobenzene (7k): 52 mg (43%)
yield, pale yellow oil, Z:E 2.7:1. IR (CH2Cl2):
= 2970, 2876, 1599,
max
(E)-2-(But-1-enyl)-5-iodonitrobenzene (7g): 36 mg (24%) yield, pale
1571, 1534, 1459, 1416, 1369, 1301, 1074, 891, 834 cm-1. Z: 1H NMR
yellow oil. IR (CH2Cl2):
= 2965, 1642, 1523, 1465, 1345, 1269,
max
(400 MHz, CDCl3): = 1.0 (t, 3JH,H = 7.5 Hz, 3H, CH3), 2.14 (m, 2H, CH2),
10176, 965, 872, 847, 818, 711 cm-1. 1H NMR (400 MHz, CDCl3):
=
3
1.11 (t, 3JH,H = 7.4 Hz, 3H, CH3), 2.27 (m, 2H, CH2), 6.30 (dt, 3JH,H = 15.6
Hz, 6.5 Hz, 1H, vinyl CH), 6.75 (d, 3JH,H = 15.6 Hz, 1H, vinyl CH), 7.31 (d,
3.88 (s, 3H, OMe), 5.85 (dt, JH,H = 11.4 Hz, 7.5 Hz, 1H, vinyl CH), 6.18
4
(m, 1H, vinyl CH), 6.87 (d, JH,H = 1.8 Hz, 1H, Harom), 6.91 (d, 4JH,H = 1.9
Hz, 1H, Harom) ppm. E: 1H NMR (400 MHz, CDCl3): = 1.06 (t, 3JH,H = 7.4
3JH,H = 8.4 Hz, 1H, Harom), 7.81 (dd, JH,H = 8.3 Hz, JH,H = 1.7 Hz, 1H,
3
4
4
Harom), 8.17 (d, JH,H = 1.7 Hz, 1H, Harom) ppm. 13C NMR (100 MHz,
Hz, 3H, CH3), 2.23 (m, 2H, CH2), 3.87 (s, 3H, OMe), 6.18 (m, 1H, vinyl
3
4
CH), 6.37 (dt, JH,H = 15.7 Hz, 6.5 Hz, 1H, vinyl CH), 6.84 (d, JH,H = 1.9
CDCl3): = 13.1, 26.3, 90.4, 123.2, 129.7, 132.8, 132.9, 139.1, 141.6,
147.9 ppm. MS (EI): m/z (%) = 303 (M+, 18), 246 (44), 218 (28), 159 (37),
131 (49), 115 (49), 91 (37), 57 (100). HRMS (EI) calcd for C10H10INO2
(M+), 302.9756; found, 302.9756.
4
Hz, 1H, Harom), 7.11 (d, JH,H = 1.8 Hz, 1H, Harom) ppm. 13C NMR (100
MHz, CDCl3): = 13.0, 13.9, 22.1, 26.2, 56.7, 111.0, 111.5, 117.9, 120.1,
120.2, 121.6, 132.4, 132.4, 136.1, 136.4, 138.6, 139.5, 140.2, 140.3,
151.4, 151.4 ppm. MS (EI): m/z (%) = 241 (M+, 12), 224 (45), 196 (45),
184 (40), 161 (71), 140 (79), 127 (77), 115 (85), 102 (54), 75 (67), 57
(100). HRMS (EI) calcd for C11H12ClNO3 (M+), 241.0506; found, 241.0511.
Anal. calcd for C11H12ClNO3: C, 54.67; H, 5.00; N, 5.80; Cl, 14.76. Found:
C, 54.62; H, 5.01; N, 5.78; Cl, 14.80.
(E)-4-(But-1-enyl)-3-iodonitrobenzene (7g’): 72 mg (48%) yield, pale
yellow oil. IR (CH2Cl2): max = 3092, 2965, 1641, 1575, 1515, 1459, 1342,
1
3
1113, 963, 736 cm-1. H NMR (400 MHz, CDCl3): = 1.15 (t, JH,H = 7.4
3
Hz, 3H, CH3), 2.33 (m, 2H, CH2), 6.36 (dt, JH,H = 15.6 Hz, 6.5 Hz, 1H,
3
3
vinyl CH), 6.61 (d, JH,H = 15.6 Hz, 1H, vinyl CH), 7.55 (d, JH,H = 8.7 Hz,
3
4
(E)-5-(But-1-enyl)-8-nitroquinoline (7l): 72 mg (63%) yield, pink
crystals (heptane–CH2Cl2). M.p. 121–123 C. IR (KBr): max = 2976, 2915,
1649, 1529, 1379, 959, 874, 830, 797, 650 cm-1. 1H NMR (400 MHz,
1H, Harom), 8.13 (dd, JH,H = 8.7 Hz, JH,H = 2.3 Hz, 1H, Harom), 8.66 (d,
4JH,H = 2.4 Hz, 1H, Harom) ppm. 13C NMR (100 MHz, CDCl3): = 13.1,
26.3, 97.8, 123.2, 126.0, 131.4, 134.5, 140.5, 146.4, 147.3 ppm. Anal.
calcd for C10H10INO2: C, 39.63; H, 3.33; N, 4.62. Found: C, 39.45; H,
3.39; N, 4.64.
3
CDCl3): = 1.10 (t, JH,H = 7.5 Hz, 3H, CH3), 2.29 (m, 2H, CH2), 6.44 (d,
3
3JH,H = 15.8 Hz, 1H, vinyl CH), 6.37 (dt, JH,H = 15.7 Hz, 6.5 Hz, 1H, vinyl
CH), 6.58 (dt, 3JH,H = 15.7 Hz, 6.4 Hz, 1H, vinyl CH), 7.41 (dd, 3JH,H = 8.3
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10.1002/ejoc.201801018
European Journal of Organic Chemistry
FULL PAPER
Hz, 4.3 Hz, 1H, Harom), 7.70 (d, 3JH,H = 8.8 Hz, 1H, Harom), 7.79 (d, 3JH,H
=
165 (35), 105 (20). HRMS (EI) calcd for C15H9F3ClNO2 (M+), 327.0274;
found, 327.0275.
3
4
8.7 Hz, 1H, Harom), 8.11 (dd, JH,H = 8.3 Hz, JH,H = 1.5 Hz, 1H, Harom),
3
4
8.89 (dd, JH,H = 4.2 Hz, JH,H = 1.5 Hz, 1H, Harom) ppm. 13C NMR (100
MHz, CDCl3): = 13.0, 26.5, 121.0, 122.2, 123.5, 127.3, 129.1, 129.4,
135.5, 139.9,140.8, 146.1, 152.2 ppm. MS (EI): m/z (%) = 228 (M+, 11),
211 (45), 199 (41), 183 (33), 171 (100), 154 (32), 142 (64), 128 (43), 116
(49), 57 (29). HRMS (EI) calcd for C13H12N2O2 (M+), 228.0899; found,
228.0892. Anal. calcd for C13H12N2O2: C, 68.41; H, 5.30; N, 12.27.
Found: C, 68.27; H, 5.23; N, 12.04.
(Z)-1-(3-Chloro-4-nitrophenyl)-2-phenyl-3,3,3-trifluoropropene (9b’):
13 mg (8%) yield, pale yellow oil. IR (CH2Cl2):
= 3063, 2928, 2858,
max
1577, 1527, 1350, 1283, 1172, 1123, 964, 907, 835, 765, 699 cm-1. 1H
NMR (400 MHz, CDCl3): = 6.99 (s, 1H, vinyl CH), 7.44 (m, 6H, Harom),
7.56 (s, 1H, Harom), 7.92 (d, 3JH,H = 8.4 Hz, 1H, Harom) ppm. 13C NMR (100
1
MHz, CDCl3): = 122.8 (q, JC,F = 276.0 Hz), 125.5, 127.2, 127,6 (m),
128.0, 128.7, 129.2, 131.7 (m), 134.2 (q, 4JC,F = 3.2 Hz), 135.7 (q, 2JC,F
=
(E,Z)-2-(But-1-enyl)-4-methoxy-3-nitropyridine (7m): 20 mg (19%)
30.3 Hz), 140.4, 147.1 ppm. 19F NMR (376 MHz, CDCl3): = 56.46 (s)
ppm. MS (EI): m/z (%) = 327 (M+, 100), 280 (42), 246 (46), 212 (68), 176
(45), 165 (39). HRMS (EI) calcd for C15H9F3ClNO2 (M+), 327.0274; found,
327.0269.
yield, pale yellow oil, Z:E 2.9:1. IR (CH2Cl2):
= 2966, 2935, 2875,
max
1703, 1645, 1589, 1532, 1469, 1367, 1304, 1065, 854, 819 cm-1. Z: 1H
NMR (400 MHz, CDCl3): = 1.04 (t, 3JH,H = 7.5 Hz, 3H, CH3), 2.56 (m, 2H,
CH2), 3.94 (s, 3H, OCH3), 6.03 (dt, 3JH,H = 11.7 Hz, 7.4 Hz, 1H, vinyl CH),
6.24 (dt, 3JH,H = 11.7 Hz, 4JH,H = 1.6 Hz, 1H, vinyl CH), 6.84 (d, 3JH,H = 5.8
(E)-1-(8-Nitroquinolin-5-yl)-2-phenyl-3,3,3-trifluoropropene (9l): 100
mg (58%) yield, pink crystals (heptane–CH2Cl2). M.p. 140–142 C. 1H
3
Hz, 1H, Harom), 8.53 (d, JH,H = 5.8 Hz, 1H, Harom) ppm. 13C NMR (100
3
MHz, CDCl3): = 13.8, 22.6, 56.4, 105.6, 119.7, 123.2, 144.5, 149.3,
NMR (200 MHz, CDCl3): = 6.95 (d, JH,H = 8.8 Hz, 1H, Harom), 7.34 (m,
1
3
3
151.2, 156.9 ppm. E: H NMR (400 MHz, CDCl3): = 1.10 (t, JH,H = 7.4
6H, vinyl CH, Ph), 7.52 (dd, JH,H = 8.4 Hz, 4.3 Hz, 1H, Harom), 7.58 (d,
3
3
4
3JH,H = 9.0 Hz, 1H, Harom), 8.11 (dd, JH,H = 8.3 Hz, JH,H = 1.6 Hz, 1H,
Hz, 3H, CH3), 2.29 (m, 2H, CH2), 3.94 (s, 3H, OCH3), 6.32 (dt, JH,H
=
15.2 Hz, 4JH,H = 1.5 Hz, 1H, vinyl CH), 6.79 (d, JH,H = 5.7 Hz, 1H, Harom),
3
Harom), 9.00 (dd, JH,H = 4.3 Hz, JH,H = 1.6 Hz, 1H, Harom) ppm. 13C NMR
(50 MHz, CDCl3): = 122.9 (q, 1JC,F = 274.3 Hz), 123.3, 124.6 (m), 125.9
(q, 3JC,F = 5.7 Hz), 126.6, 126.7, 128.3, 128.9, 128.9, 129.5, 129.8, 131.0,
3
4
3
3
7.14 (dt, JH,H = 15.1 Hz, 6.7 Hz, 1H, vinyl CH), 8.46 (d, JH,H = 5.7 Hz,
1H, Harom) ppm. 13C NMR (100 MHz, CDCl3): = 12.8, 26.0, 56.5, 105.5,
120.6, 126.4, 143.8, 148.0, 151.5, 159.6 ppm.
2
135.6, 137.1 (q, JC,F = 31.0 Hz), 139.3, 152.7 ppm. Anal. calcd for
C18H11F3N2O2: C, 62.79; H, 3.22; N, 8.14. Found: C, 62.71; H, 3.18; N,
8.33.
(E,Z)-2-(3-Chloro-4-nitrophenyl)-2-pentene (8b): 15 mg (13%), pale
yellow oil, E:Z = 3:1. IR (CH2Cl2):
= 2967, 2873, 1587, 1523, 1345,
max
1045, 859, 835 cm-1. E: 1H NMR (400 MHz, CDCl3): = 1.08 (t, JH,H
=
3
Alkene 10: 21 mg (13%), orange oil. IR (CH2Cl2):
= 3058, 2931,
max
4
1712, 1607, 1563, 1523, 1469, 1377, 1337, 1104, 914, 749 cm-1. 1H
7.5 Hz, 3H, CH3), 2.02 (d, JH,H = 1.1 Hz, 3H, CH3), 2.24 (m, 2H, CH2),
5.94 (tq, 3JH,H = 7.2 Hz, 4JH,H = 1.3 Hz, 1H, vinyl CH), 7.36 (dd, 3JH,H = 8.6
Hz, 4JH,H = 2.0 Hz, 1H, Harom), 7.50 (d, 4JH,H = 2.0 Hz, 1H, Harom), 7.86 (d,
3JH,H = 8.6 Hz, 1H, Harom) ppm. 13C NMR (100 MHz, CDCl3): = 13.7,
15.2, 22.3, 124.3, 125.8, 127.3, 128.8, 131.6, 135.1, 145.6, 149.5 ppm.
NMR (200 MHz, CDCl3): = 3.28 (s, 3H), 6.84 (m, 3H), 7.28 (m, 1H),
3
4
4
7.60 (dd, JH,H = 8.9 Hz, JH,H = 2.3 Hz, 1H), 7.68 (d, JH,H = 2.2 Hz, 1H),
7.98 (s, 1H), 8.27 (d, 3JH,H = 8.9 Hz, 1H) ppm. 13C NMR (50 MHz, CDCl3):
= 26.2, 108.6, 120.1, 122.1, 122.6, 126.9, 129.0, 130.0, 130.7, 130.8,
131.2, 133.2, 140.4, 144.7, 145.5, 167.2 ppm.
1
Z: H NMR (400 MHz, CDCl3): = 0.95 (t, 3JH,H = 7.5 Hz, 3H, CH3), 1.96
3
4
(m, 2H, CH2), 2.01 (m, 3H), 5.58 (tq, JH,H = 7.5 Hz, JH,H = 1.4 Hz, 1H,
3
4
vinyl CH), 7.19 (dd, JH,H = 8.4 Hz, JH,H = 1.8 Hz, 1H, Harom), 7.34 (d,
3
4JH,H = 1.8 Hz, 1H, Harom), 7.87 (d, JH,H = 8.3 Hz, 1H, Harom) ppm. 13C
Acknowledgements
NMR (100 MHz, CDCl3): = 14.3, 22.5, 24.7, 125.6, 127.0, 127.2, 131.3,
132.4, 132.7, 145.1, 148.2 ppm.
Financial support from the National Science Centre, Poland, is
(E)-1-(3-Chloro-2-nitrophenyl)-2-phenyl-3,3,3-trifluoropropene
(E-
gratefully
2017/25/B/ST5/00214).
acknowledged
(Grant
Opus
UMO-
9b): 24 mg (14%) yield, pale yellow oil. IR (CH2Cl2):
= 3064, 2891,
max
1538, 1365, 1294, 1270, 1169, 1128, 963, 850, 794, 706, 626 cm-1. 1H
3
NMR (400 MHz, CDCl3): = 7.91 (d, JH,H = 7.9 Hz, 1H, Harom), 7.09 (t,
3JH,H = 8.1 Hz, 1H, Harom), 7.13 (d, 4JH,F = 1.4 Hz, 1H, vinyl CH), 7.23 (m,
Keywords: Nucleophilic substitution • Olefination • Carbanions •
2H, Harom), 7.34 (m, 4H, Harom) ppm. 13C NMR (100 MHz, CDCl3):
=
Elimination • Arenes
122.8 (q, 1JC,F = 274.3 Hz), 125.5, 126.0 (q, 3JC,F = 6.1 Hz), 128.6, 128.7,
128.9, 129.1, 129.4, 129.6, 130.4, 130.8, 136.9 (q, 2JC,F = 30.4 Hz), 149.3
ppm. 19F NMR (376 MHz, CDCl3): = -66.22 (s) ppm. MS (EI): m/z (%) =
327 (M+, 11), 280 (13), 245 (21), 230 (57), 213 (36), 176 (42), 153 (100),
125 (83), 105 (47). HRMS (EI) calcd for C15H9F3ClNO2 (M+), 327.0274;
found, 327.0282.
[1]
a) J. Yamaguchi, A. D. Yamaguchi, K. Itami, Angew. Chem. Int. Ed.
2012, 51, 8960-9009; b) S. A. Girard, T. Knauber, C.-J. Li, Angew.
Chem. Int. Ed. 2014, 53, 74-100; c) M. Gulías, J. L. Mascareñas,
Angew. Chem. Int. Ed. 2016, 55, 11000-11019.
[2]
[3]
a) Y. Fujiwara, I. Moritani, S. Danno, R. Asano, S. Teranishi, J. Am.
Chem. Soc. 1969, 91, 7166–7169; b) T. Nishikata, B. H. Lipshutz, Org.
Lett. 2010, 12, 1972–1975.
(Z)-1-(3-Chloro-2-nitrophenyl)-2-phenyl-3,3,3-trifluoropropene (Z-9b):
32 mg (20%) yield, colourless crystals (heptane–CH2Cl2). M.p. 75–77 C.
a) S. Prakash, K. Muralirajan, C.-H. Cheng, Chem.Commun. 2015, 51,
13362-13364; b) K. D. Otley, J. A. Ellman, Org. Lett. 2015, 17, 1332-
1335; c) Y. Takahama, Y. Shibata, K. Tanaka, Chem. Eur. J. 2015, 21,
9053–9056; d) W.-B. Qin, W.-W. Li, P.-F. Zhu, X.-G. Mo, H.-J. Zhang,
T.-B. Wen, Org. Chem. Front. 2018, 5,1096–1100.
IR (KBr):
= 3100, 3060, 2925, 2859, 1968, 1896, 1576, 1524, 1347,
max
1268, 1161, 1116, 923, 835, 699 cm-1. 1H NMR (400 MHz, CDCl3):
=
3
6.98 (d, JH,H = 8.6 Hz, 1H, Harom), 7.19 (m, 2H, Harom), 7.25 (m, 2H,
Harom), 7.43 (m, 3H, Harom), 7.65 (d, JH,H = 8.5 Hz, 1H, Harom) ppm. 13C
3
1
[4]
[5]
Catalytic Hydroarylation of Carbon-Carbon Multiple Bonds, Eds.: L.
Ackermann, T. B. Gunnoe, L. G. Habgood, Wiley-VCH, Weinheim,
2018.
NMR (100 MHz, CDCl3): = 123.0 (q, JC,F = 273.9 Hz), 125.4, 127.2,
128.5, 129.3, 129.4, 129.7, 129.7 (m), 131.1, 133.0, 135.2 (q, 2JC,F = 30.2
Hz), 139.1, 147.0 ppm. 19F NMR (376 MHz, CDCl3): = -66.62 (s) ppm.
MS (EI): m/z (%) = 327 (M+, 100), 281 (51), 246 (66), 212 (68), 176 (46),
a) M. Mąkosza, J. Winiarski, Acc. Chem. Res. 1987, 20, 282-289; b) M.
Mąkosza, Chem. Eur. J. 2014, 20, 5536-5545; c) K. Błaziak, W.
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FULL PAPER
Danikiewicz, M. Mąkosza, J. Am. Chem. Soc. 2016, 138, 7276-7281; d)
M. Mąkosza, Synthesis 2017, 3247-3254.
[12] a) G. Yan, M. Yang, Org. Biomol. Chem. 2013, 11, 2554-2566; b) M.-Y.
Chang, H.-Y. Chen, H.-S. Wang, J. Org. Chem. 2017, 82, 10601-10610.
[13] a) S. Tong, Z. Xu, M. Mamboury, Q. Wang, J. Zhu, Angew. Chem Int.
Ed. 2015, 54, 11809-11812; b) N. Jana, F. Zhou, T. G. Driver, J. Am.
Chem. Soc. 2015, 137, 6738–6741; c) M. Shevlin, X. Guan, T. G.
Driver, ACS Catal. 2017, 7, 5518–5522.
[6]
[7]
M. Mąkosza, K. Wojciechowski, Liebigs Ann. 1997, 1805-1816.
a) D. A. Jackson, N. J. Lawrence, J. Liddle, Synlett 1996, 55-56; b) S.
Florio, P. Lorusso, C. Granito, L. Ronzini, L. Troisi, Eur. J. Org. Chem.
2003, 4053-4058.
[8]
[9]
a) S. Florio, P. Lorusso, C. Granito, R. Luisi, L. Troisi, J. Org. Chem.
2004, 69, 4961-4965; b) A. Sakowicz, R. Loska, M. Mąkosza, Synlett
2016, 2443-2446.
[14]
-
, R. Loska, M. Mąkosza, J. Org. Chem. 2016, 81,
11751−11757
[15] M.-E. Lebrun, P. Le Marquand, C. Berthelette, J. Org. Chem. 2006, 71,
2009-2013.
a) M. Makosza, K. Bester, P. Cmoch, J. Org. Chem. 2015, 80, 5436-
5443; b) J. Brześkiewicz, R. Loska, M. Mąkosza, J. Org. Chem. 2018,
DOI: 10.1021/acs.joc.8b01091.
[16] B. Górski, D. Basiak, A. Talko, T. Basak, T. Mazurek, M. Barbasiewicz,
Eur. J. Org. Chem. 2018, 1774-1784.
[10] (a) P. R. Blakemore, J. Chem. Soc., Perkin Trans. 1 2002, 2563-2585;
b) C. Aïssa, Eur. J. Org. Chem. 2009, 1831-1844. (c) P. R. Blakemore,
S. Milicevic Sephton, E. Ciganek, Org. React. 2018, 95, 1-422.
[11] a) N. J. Lawrence, J. Liddle, D. Jackson, J. Chem. Soc., Perkin Trans 1
2002, 2260-2267; b) G. Iakobson, P. Beier, Beilstein. J. Org. Chem.
2012, 8, 1185-1190.
[17] S. Domański, W. Chaładaj, ACS Catal. 2016, 6, 3452-3456.
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Entry for the Table of Contents (Please choose one layout)
Layout 2:
FULL PAPER
C–H Alkenylation
Rafał Loska*
R2
R1
R1
1) KHMDS
R2
R3
Page No. – Page No.
+ Cl
2) LiCl, R3COR4
C–H-Alkenylation of Arenes in a One-
pot VNS – Julia-Kocienski Reaction
R4
O2S BT
O2N
O2N
Text for Table of Contents
C–H bonds in nitroarenes and heteroarenes can be efficiently functionalized with alkene moieties in a one-pot, two-step
reaction sequence without the need for transition metal catalysis. The resulting two- or three-substituted double bonds are
formed usually with complete E selectivity.
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