tert-Butyl Nitrite Mediated Nitro-Nitratosation of Internal Alkenes

Article abstract of DOI:10.1002/ejoc.202000149

In an oxygen atmosphere tert-butyl nitrite (TBN) reacts with unsymmetrical internal benzylic alkenes giving nitro-nitratosation product exclusively. The γ-diaryl-substituted styrenes provided better yields compared to γ-alkyl-aryl-substituted styrenes. The higher yields for the former type of substrates is possibly dictated by the additional stability of benzylic radical due to the anchimeric assistance imparted by the γ-substituted phenyl ring. During oxidative nitration, the nitro (NO₂) group adds at the non-benzylic site, whereas the nitrato group (ONO₂) is attached at the relatively stable benzylic position. Under similar reaction conditions, α,β-unsaturated carboxylic acids, afforded nitroalkenes as the sole product.

Full text of DOI:10.1002/ejoc.202000149

European Journal of Organic Chemistry
Accepted Article
Accepted Article
Title: tert-Butyl Nitrite Mediated Nitro-Nitratosation of Internal Alkenes
Authors: Bilal Ahmad Mir, Suresh Rajamanickam, Pakiza Begum, and
Bhisma Kumar Patel
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To be cited as: Eur. J. Org. Chem. 10.1002/ejoc.202000149
Link to VoR: https://doi.org/10.1002/ejoc.202000149
01/2020

10.1002/ejoc.202000149
European Journal of Organic Chemistry
FULL PAPER
DOI: ((will be filled in by the editorial staff))
tert-Butyl Nitrite Mediated Nitro-Nitratosation of Internal
Alkenes
Bilal Ahmad Mir,a Suresh Rajamanickam,a Pakiza Begum,a and Bhisma K. Patela,*
Received: ((will be filled in by the editorial staff))
Supporting information for this article is available on the WWW under http://dx.doi.org/######.((Please delete if not
appropriate))
Abstract: In an oxygen atmosphere tert-butyl nitrite (TBN) reacts with unsymmetrical internal benzylic
alkenes giving nitro-nitratosation product exclusively. The -diaryl substituted styrenes provided better yields
compared to -alkyl-aryl substituted styrenes. The higher yields for the former type of substrates is possible
dictated by the additional stability of benzylic radical due to the anchimeric assistance imparted by the -
substituted phenyl ring. During oxidative nitration, the nitro (NO2) group adds at the non-benzylic site, whereas
the nitrato group (ONO2) is attached at the relatively stable benzylic position. Under similar reaction conditions,
α,β-unsaturated carboxylic acids, afforded nitroalkenes as the sole product.
Keywords: tert-Butyl nitrite (TBN); oxidative nitration; nitro alkenes; internal alkenes, -attack.
Introduction
The metal-free reagent, tert-butyl nitrite (TBN) is
emerging as a multi-tasking reagent in various
synthetic applications because of its easy availability,
easy handling, low cost, and stability.[1] Thermolysis of
TBN provides NO and tBuO radicals. The former can
directly participate in a reaction, whereas both of these
radicals can initiate several reactions. Due to the
intrinsic ability of TBN to activate molecular oxygen
it captures dioxygen generating a NO2 radical, which
prompts nitration and many other oxidation processes.
Interestingly, the NO radical is a good acceptor of
transient radicals thus serving as an efficient radical
trapper and source of N and N-O synthons.[1]
Terminal alkenes such as styrene react differently
with TBN depending upon the other additives present
in the reaction. Styrenes react with TBN in the
presence of Fe(II) catalyst and NaBH4 to give
corresponding oximes.[2] Treatment of styrene with
TBN in an air atmosphere in toluene at room
temperature provided -nitroalcohol along with some
nitrated products (Scheme 1c).[3] Styrenes undergo
cross-coupling in the presence of metal-based carbene
and NO radical (generated in situ from TBN)
providing isooxazolines.[4] In this process, styrene
serve as a dienophile and undergo [3+2]cycoaddition
in situ generated nitrile oxide intermediate. Following
the analogous [3+2] cycloaddition strategy our group
obtained symmetrical isoxazolines from styrenes in
the presence of TBN, Sc(OTf)3 and quinoline.[5] While
quinoline did not participate and serve only as a base
during the formation of isoxazolines. However, in a
Cu-catalyzed process, it took part along with the
styrene and TBN providing imidazo[1,2-a]quinolines
via a three-component process. Here, TBN serves the
dual role of an N1 synthon as well as an oxidant.[6] In
the absence of any other additives, styrene analogues
react with TBN in DMSO providing 1,2,4-oxadiazole-
5(4H)-ones.[7] Sulfonyl hydrazide as sulfonyl radical
and TBN as the NO source adds across the styrene
double bond to give a bi-functionalized product -
sulfonylethanone oximes, which is mediated by a
base.[8] Similarly,-sulfonylethanone oxime is
obtained from styrene, where TOsMIC acts as the
sulfonyl source and TBN as the NO source as well as
an oxidant.[9] Using sulfinic acids as the sulfonating
agent and TBN as the NO source as well as an oxidant a
vicinal sulfoximation of styrene has been
accomplished.[10a] TBN has also been employed for the
stereoselective nitration,[10b] aerobic oxynitration of
terminal olefins,[10c] metal-free nitration of 2-
oxindoles,[10d] metal-freesynthesisofisatins,[10e] synthesis
of quinoxaline N-oxides,[10f] cascade nitration/cyclization
of 1,7enynes,[10g] and nitration-peroxidation of styrenes,
where the TBN serves as a NO source and TBHP as a
tBuOO source (Scheme 1f).[10h] From the above
[a]
B. A. Mir, S. Rajamanickam, Dr. P. Begum, Prof.
Dr. B. K. Patel
Department of Chemistry, Indian Institute of Technology
Guwahati, 781039, Assam, India. E-mail: patel@iitg.ac.in
https://www.iitg.ac.in/patel/
1
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10.1002/ejoc.202000149
European Journal of Organic Chemistry
literature reports, it is evident that TBN reacts with
styrenes in many ways depending on the reaction
conditions and other additives present. On the other hand,
internal benzylic and non-benzylic alkenes also react
differently with TBN. An interesting synthesis of
furoxane is accomplished from benzylic internal alkene
using TBN, quinoline and K2S2O8 (Scheme 1e). Under a
similar condition -unsaturated carboxylic acids and
cyclic internal alkene afforded nitroalkenes.[11]
exclusively a mono nitro product where the nitro group
is at the benzylic position -carbon) (Scheme 1f).
Surprisingly, compared to all other previous results[5-7]
this is an unusual attacking position for the nitro group
as it always prefers to attack at the -position (Scheme
1a-d).[11] Styrenes react with TBN in an oxygen
atmosphere to give -nitro alcohols and their nitrate
derivatives, where the exclusive attack of the NO2
group is at the terminal carbon of the styrene (Scheme
1c).[3] Thus, instead of a terminal alkene (styrene) if an
internal alkene such as -diaryl substituted or -alkyl-
aryl substituted styrene is treated with TBN under an
oxygen atmosphere will they react similarly or behave
differently giving different products? Further, if
mono-nitration takes place will it be at the  or at the
-position of the internal benzylic alkenes? Therefore,
we were curious to investigate the reaction of various
internal alkenes with TBN in an oxygen atmosphere.
Results and Discussion
Our initial investigation started by reacting -diaryl
substituted internal alkene (1) with tert-butyl nitrite
(a). Initially, alkene (1) was treated with tert-butyl
nitrite (a) (2 equiv.) in chlorobenzene (2.0 mL) at room
temperature for 24 h in an air atmosphere. A new
product (1a) was isolated in 39% yield after column
chromatographic separation (Table 1, entry 1).
1
Spectroscopic (IR, H and 13C NMR) analysis of the
product (1a) revealed the disappearance of both alkene
protons at 6.60 ppm and 6.40 ppm. However, the
appearance of two doublets one at 5.87 ppm and
another at 4.88 ppm along with a multiplet at 5.69 ppm
suggests that the PhCH(Ph)- part is intact thereby
confirming di-functionalization across the double
bond of (1). Further, HRMS analysis of the product
indicates the loss of two protons and the addition of
NO2 and ONO2 groups. Eventually, the exact structure
of the product was confirmed by X-ray
crystallographic analysis of one of its derivative (10a)
as shown in Figure 1.
Scheme 1. Various methods for nitration of alkenes.
During the formation of isoxazoline,[4,5]
imidazo[1,2-a]quinolines,[6] and 1,2,4-oxadiazole-
5(4H)-ones[7] from styrenes and TBN, the in situ
generated NO2 radical attacks at the -carbon while the
NO radical attacks at the -carbon even though both
the radicals coexist in the medium. From the
computational calculation, it was found that the attack
of NO2 radical at the terminal carbon that is at the -
carbon is stabilised by around 6 kcal/mole less than the
attack by NO radical at the same site.[7] During the
furoxane formation from internal alkenes viz. (E)-1,3-
diphenyl-1-butenes, the NO2 radical again attacks at the
-carbon while the NO radical at the benzylic position
(i.e -carbon) leading to the formation of furoxane
(Scheme 1e).[11] However, in an analogous internal
alkene viz. prop-2-ene-1,1,3-triyltriaryl system gave
Figure 1. ORTERP molecular diagram of (10a)[12]
Fascinated by the formation of this oxidative
nitration product (1a), this reaction was further
screened by varying various other solvents. Among the
solvents screened such as CH3CN, DCE, DMSO,
DMF, MeOH and THF (Table 1, entries 26) the polar
2
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10.1002/ejoc.202000149
European Journal of Organic Chemistry
aprotic solvent CH3CN (Table 1, entry 2) was found to
give the best yield of (1a) in 48% under otherwise
identical condition. Gratifyingly, when the same
reaction was performed in an oxygen atmosphere, the
product (1a) was obtained in an improved yield of 65%
(Table 1, entry 7). To see if the use of a metal catalyst
can help improve the yield, various metal catalysts
such as Cu(OAc)2, CuCl2, Cu(acac)2, CuO, Cu2O, FeCl3
were employed but none provided any improved yield
of the product (1a) compared to the uncatalyzed
reaction (Table 1, entries 814). Interestingly, when
the reaction was performed at 0 °C under otherwise
identical reaction conditions provided the desired
product (1a) in improved yield of 74% (Table 1, entry
15). On the other hand, when the reaction was
performed at 50 °C, the yield of (1a) dropped
drastically to 11%, possibly due to competitive side
reactions among various radicals (Table 1, entry 16).
internal benzylic alkenes possessing moderately
electron-donating groups such as p-Me (2), m-Me (3),
p-tBu (4), p-Ph (5), p-CH2Cl (6) gave their
corresponding oxidative nitration products (2a, 67%),
(3a, 65%), (4a, 62%), (5a, 64%), (6a, 64%) in moderate
yields (Scheme 2). Internal benzylic alkenes bearing
moderately electron-withdrawing groups such as p-Cl
(7), m-Cl (8), p-Br (9) and p-F (10) in their phenyl rings,
provided their corresponding products (7a, 75%), (8a,
73%), (9a, 75%) and (10, 77%), in good yields as
shown in (Scheme 2). Alkene possessing strongly
electron-withdrawing group such as m-NO2 (11) also
underwent oxidative nitration and provided the
corresponding product (11a) in 68% yield. As can be
seen from the pattern in the yield obtained, phenyl ring
possessing moderately electron-withdrawing groups
provided better yields than substrates having electron-
donating groups. This yield trend is not pronounced for
a substrate having strongly electron-withdrawing
groups such as nitro suggesting some additional factors
may be responsible for it. Alkene having a polycyclic
ring such as 2-naphthyl (12) at the double also delivered
the desired oxidative nitration product (12a) in
moderate yield (Scheme 2). In addition to simple phenyl
rings at the -position (1-12) substituted phenyl rings
(1316) all reacted efficiently. -Phenyl rings having
electron-donating p-Me (13), p-Et (14) as well as
electron-withdrawing p-Cl (15), p-F (16) all reacted
successfully and provided their corresponding
oxidative nitration products (13a, 73%), (14a, 75%) and
(15a, 77%), (16a, 79%) in good yields (Scheme 2). An
alkene (17) where both the -phenyl rings are locked
through the C(CH3)2 unit also reacted successfully and
provided the expected product (17a) in a good yield of
74%. As can be seen from Scheme 2, -diaryl
substituted styrene (1) provided the better yield of the
product compared to -alkyl-aryl substituted styrene
(18) even though the benzylic radical formed is away.
The higher yield of the product (1a) obtained for the
substrate (1) may be due to additional stability of the
benzylic radical imparted by the -phenyl ring through
anchimeric assistance. However, such type of
assistance is missing for substrate (18). The same trend
was also observed for two other substrates (19) and (20)
providing their products (19a, 57%) and (20a, 52%) in
lesser yields. Under the present reaction conditions
when this method was applied to other terminal alkenes
such as styrene or vinylcyclopentane none provided
nitro-nitrosation product. Interestingly, both gave their
respective isooxazolines, which is consistent with our
earlier report.[5,11]
Table 1. Screening of reaction conditions[a]
Entry
Catalyst
(10 mol %)
Solvent
Yield
(%)[b]
39[c]
48[c]
23[c]
38[c]
14[c]
18[c]
65[d]
27[d]
23[d]
24[d]
22[d]
45[d]
34[d]
11[d]
74[d,e]
11[e,f]
PhCl
CH3CN
DCE
DMSO
DMF
MeOH
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
CH3CN
1.
2.
3.
4.
5.
6.
7.
8.
Cu(OAc)2
CuCl2
Cu(acac)2
CuO
Cu(OTf)2
Cu2O
FeCl3
9.
10.
11.
12.
13.
14.
15.
16.
[a]Reaction conditions: 1 (0.5 mmol), tert-butyl nitrite (1.0
mmol) solvent (2.0 mL). [b]Yield after 24 h. [c]Under an air
atmosphere. [d]In the presence of O2 (balloon). [e]Temperature
0 °C. [f]Temperature 50 °C.
After a series of screening experiments, it was found
that this bis-functionalization is best achieved using
alkene (1) (0.5 mmol), TBN (2 equiv.) at 0 °C for 24 h.
After establishing the optimized reaction condition for
this oxidative nitration as shown in (Table 1), we
explored the reaction of various (E)-prop-2-ene-1,1,3-
triyltribenzenes (117) with TBN (a). This reaction
proceeds well with a variety of internal alkenes (117)
bearing electron-donating as well as electron-
withdrawing groups in their phenyl ring attached
directly to the double bond. Phenyl rings of these
To check whether the reaction is proceeding via a
radical path, alkene (1) was reacted with tert-butyl
nitrite (a) in the presence of an equimolar quantity of
radical scavenger (2,2,6,6-tetramethylpiperidin-1-
yl)oxidanyl (TEMPO). Formation of (<8%) of the
product (1a), suggests a possible radical pathway. In
order to ascertain, whether molecular oxygen is
3
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10.1002/ejoc.202000149
European Journal of Organic Chemistry
Scheme 2. Substrate scope for nitro-nitratosation. Reaction conditions: 117 (0.50 mmol), tert-butyl nitrite (1.0 mmol) in
CH3CN (2.0 mL) at 0 oC for 24 h. Isolated yields.
involved in the product formation or not, a reaction was
performed under an atmosphere of nitrogen keeping all
other parameters identical. Under
a
nitrogen
atmosphere the reaction did not yield the desired
product (1a) and most of the starting material remained
unreacted thereby, suggesting the involvement of
molecular oxygen in the product formation. No 18O
labelled product was obtained when the reaction was
carried out in the presence of an equivalent of 18O
labelled water. Taking cues from the above reactions
and on the basis of the literature reports,[13] a plausible
mechanism has been proposed for this nitro
nitratosation. Initially, tert-butyl nitrite reacts with
molecular oxygen to generate NO2 radical via
peroxynitrite radical (ONOO•) intermediate (Scheme 4,
path-I).[13] Alternatively, the nitro radical can also be
obtained by the reaction of TBN with water generating
HNO2, decomposition of which would give NO2 radical
(Scheme 4, path-II).[3,13d-f] The NO2 radical so generated
then attacks at the nonbenzylic carbon of the internal
Scheme 3. Plausible mechanism for nitro nitratosation.
4
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10.1002/ejoc.202000149
European Journal of Organic Chemistry
alkene (1) to form a nitroalkane benzyl radical give the product (1a) (Scheme 3). This proposed
intermediate (A) (Scheme 3). The benzylic radical mechanism is well supported by DFT calculations as
intermediate (A) then reacts with the molecular O2 to shown in Figure 2. Based on experimental results, we
generate a peroxy radical intermediate (B). The have considered a credible mechanistic design which
intermediate (B) reacts further with TBN (a) to give has been studied using Density Functional Theory
intermediate (C) via the transfer of NO radical. The O- (DFT) in order to verify our findings. This plausible
O bond cleavage of intermediate (C) generates an mechanistic approach is depicted in Figure 2. All DFT
oxyradical intermediate (D) via the loss of a NO2 radical calculations have been accomplished using 6-
(Scheme 3). The intermediate (D) reacts with NO2 31+G(d,p) basis set for the atoms present in the system
radical where the electron is localized at the N atom to at M06[14a] level of theory.
Figure 2. Calculated energy profile diagram for the nitro-nitratosation nitration reaction. The relative energies from DFT
calculations are in kcal.mol-1 at M06/6-31g+(d,p) level of theory. The relative energies are shown in blue color, activation
barrier in italic bold and stabilization energy in normal font are given in kcal.mol-1.
GAUSSIAN 09 program package has been utilized to supporting information. The reaction starts with the
perform the calculation.[14b,c] Frequency calculations attack of NO2 radical at the internal C=C thereby
have been done on all modelled structures with the generating another free radical (A) at the benzylic
same level of theory. The reaction coordinates of all the position; which is stabilized by releasing an energy of
species involved {i.e. reactants, intermediates, 11.19 kcal.mol-1 and formed by crossing a barrier height
transition states (TSs) and products} along with the of 0.27 kcal.mol-1. The intermediate benzylic radical
energy values are provided in the supporting attack a molecular oxygen forming a peroxy radical
information. The optimized geometries of the various intermediate (B) involving a barrier of 0.83 kcal.mol-1
structures involved in the reaction, as well as selected and releasing 17.54 kcal.mol-1 of energy. At this stage,
bond lengths are provided in Figure S1 of the the NO radical generated from TBN attacks the
5
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10.1002/ejoc.202000149
European Journal of Organic Chemistry
intermediate (B) forming an intermediate (C) in which (a) is serving as a decarboxylative nitrating agent. Prior
the transition state is associated with a barrier of 1.28 to this report, there are reports on decarboxylative
[15a-c]
kcal.mol-1 and releases energy of 26.83 kcal.mol-1. The nitration of trans-cinnamic acid using HNO3
t
intermediate (C) upon decomposition generates an BuONO in combination with CuCl,[15d] TEMPO,[15e]
unstable oxy-radical intermediate (D) by crossing and K2S2O8.[11] These decarboxylations have been
energy barrier of 27.26 kcal.mol-1 and releasing energy achieved either using metal catalyst or the use of harsh
of 5.42 kcal.mol-1 which is the rate determining step in reaction conditions such as high temperature, highly
the proposed reaction mechanism. The radical acidic conditions stoichiometric amounts of metal
intermediate (D) readily gets attached to the N-site of nitrates or stoichiometric amounts of additives.[15]
the NO2 radical and the process is stabilized by Compared to all the methods reported our present
releasing 39.70 kcal.mol-1 of energy and formed by method is the mildest as it is achieved in the absence of
crossing a height of 1.13 kcal.mol-1. In the case of any other additives.
intermediate (C), the NO2 is linked to the O-atom of the
To explore the generality of this strategy, the
benzylic position with O-site of NO2; whereas, in the reaction of trans-cinnamic acid having moderately
final product (1a) the NO2 group is attached through its electron-donating such as p-Me (22) and strongly
N-site. Further, from the energy profile diagram, we electron-donating group such as p-OMe (23) both
could see that the final product (1a) is energetically provided their corresponding products (22a, 63%),
more favourable as compared to intermediate (C) by (23a, 61%), in moderate yields. The moderately
38.57 kcal.mol-1 of energy. The overall reaction is electron-withdrawing groups such as p-Cl (24), p-Br
found to be exothermic in nature. Thus, the theoretical (25), p-F (26) and strongly electron-withdrawing
findings are in good agreement with the proposed groups such as p-Cl-m-NO2 (27) cinnamic acids all
mechanism.
reacted successfully and delivered their corresponding
nitroalkenes (24a, 68%), (25a, 70%), (26a, 71%),
(27a, 76%), in moderate to good yields. This strategy
is equally successful even for a sterically crowded
(28), and multinuclear (29) alkene carboxylic acids
both provided their corresponding products (28a,
59%) and (29a, 57%) in moderate yields (Scheme 4).
Scheme 4. Nitration of α,β-Unsaturated carboxylic acids.
Reaction conditions: 2129 (0.50 mmol), tert-butyl nitrite
(1.0 mmol) in CH3CN (2.0 mL) at 100 oC for 24 h. Isolated
yield.
Scheme 5. Plausible mechanism for decarboxylative
nitration.
Further, to check whether this nitro nitratosation
strategy is applicable to other internal alkenes such as
α,β-unsaturated acids or not? trans-cinnamic acid (21)
To account for the formation of nitroalkenes from
-unsaturated carboxylic acids, a mechanism as
depicted in Scheme 5 (path I) has been suggested
which is similar to previously proposed one. The
trans-cinnamic acid reacts with tBuO radical and form
a nitro benzylic intermediate (E), which upon
decarboxylation gives nitroalkene (21a) (Scheme
5).[15e] Alternatively, a sequence of CO2 elimination
followed by a radical (NO2) coupling cannot be ruled
out (path II). To validate the later path a Density
Functional Theory (DFT) calculation was attempted
but unfortunately the desired transition state could not
o
was reacted with TBN (a) at 100 C otherwise under
identical reaction conditions. The reaction proceeded
well and provided a new product (21a). Spectroscopic
1
(IR, H and 13C NMR) analysis of the isolated product
(21a) showed the absence of COOH group. The HRMS
analysis of the new product revealed the loss of a
COOH group and incorporation of a NO2 group. The
reaction of corresponding ester (ethyl cinnamate) with
TBN did not yield any trace of the nitroalkene nor any
oxidative nitration product. Thus the tert-butyl nitrite
6
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10.1002/ejoc.202000149
European Journal of Organic Chemistry
be obtained even after repeated attempts. This may be
possibly due to the formation of an extremely unstable
vinylradical intermediate (F), thus ruling out the later
pCaothn. clusion
General Procedure for the Synthesis of E-(2-
Nitrovinyl)benzene (21a)
To an oven-dried 25 mL double neck round bottom
flask were added trans-cinnamic acid (74 mg, 0.5
mmol) and fitted with reflux condenser. The reaction
setup was subjected to the vacuum for 10 minutes.
tert-Butyl nitrite (0.119 mL, 1.0 mmol) was purged
into 2.0 mL of acetonitrile, the TBN containing
acetonitrile was introduced into the reaction setup in
an oxygen atmosphere. Then the reaction mixture was
refluxed at 100 oC for 24 h. After the completion of the
reaction excess solvent was evacuated under reduced
pressure. The reaction mixture was admixed with ethyl
acetate 20 mL washed with water (2 x 10 mL). The
separated organic layer was dried over anhydrous
sodium sulphate (Na2SO4), and evaporated under
reduced pressure. The crude product so obtained was
purified by silica gel column chromatography using
hexane as the eluent to give pure E-(2-
nitrovinyl)benzene (21a, 49 mg, 67% yield). The
identity and purity of the product was confirmed by
spectroscopic analysis.
In conclusion, we have demonstrated the
differential reactivity of TBN with internal benzylic
alkenes in an oxygen atmosphere, which provided
nitro-nitrosation products. This result is in contrast to
the furoxane formation for the same substrate with
TBN but in the presence of K2S2O8. The -diaryl
substituted styrenes provided better yields compared
to -alkyl-aryl substituted styrenes possibly due to
anchimeric assistance imparted by the -phenyl ring.
While α,β-unsaturated esters are inert to TBN but α,β-
unsaturated acids provided corresponding nitroalkenes
via decarboxylation. Even though other radical species
coexist in the medium the nitro radical attacks
exclusively at the -carbon in internal benzylic
alkenes. A plausible mechanism has been proposed
which is supported by DFT calculation.
Experimental Section
2-Nitro-1,3,3-triphenylpropyl nitrate (1a): Yellow
gummy, (140 mg, 61%). 1H NMR (400 MHz, CDCl3)
δ 7.36–7.31 (m, 10H), 7.28 (bs, 1H), 7.25–7.19 (m,
4H), 5.87 (d, J = 5.0 Hz, 1H), 5.69 (dd, J = 11.4, 5.0
Hz, 1H), 4.88 (d, J = 11.4 Hz, 1H) ppm. 13C NMR (101
MHz, CDCl3) δ 138.14, 138.12, 133.04, 130.02,
129.78, 129.33, 129.23, 128.25, 128.10, 127.87,
General Information:
All the reagents were commercial grade and
purified according to the established procedures.
Organic extracts were dried over anhydrous sodium
sulphate. Solvents were removed in a rotary
evaporator under reduced pressure. Silica gel (100-200
mesh size) was used for the column chromatography.
Reactions were monitored by TLC on silica gel 60 F254
(0.25 mm). NMR spectra were recorded in CDCl3 with
tetramethylsilane as the internal standard for 1H NMR
(400 and 600 MHz) and in for 13C NMR (101 and 151
MHz) CDCl3 as the internal standard. HRMS spectra
were recorded using +ESI (TOF) mode. IR spectra
were recorded in KBr or neat.
127.63, 126.08, 93.51, 80.40, 52.09.ppm. IR (KBr): ν
= 3032, 2913, 1646, 1556, 1493, 1453, 1363, 1272,
1031, 903, 828, 746, 695 cm-1. HRMS (ESI/Q-TOF)
̃
m/z: [M + Na]+ Calcd for C21H18N2NaO5 401.1108,
Found 401.1116.
2-Nitro-3,3-diphenyl-1-(p-tolyl)propyl nitrate (2a):
1
Yellow solid, (131 mg, 67%); m.p. 110114 °C. H
NMR (400 MHz, CDCl3) δ 7.35 (d, J = 7.6 Hz, 2H),
7.31 (d, J = 4.4 Hz, 5H), 7.28–7.21 (m, 4H), 7.11 (d, J
= 4.0 Hz, 3H), 5.83 (d, J = 5.2 Hz, 1H), 5.67 (dd, J =
11.6, 5.2 Hz, 2H), 4.87 (d, J = 11.6 Hz, 1H), 2.30 (s,
3H) ppm. 13C NMR (CDCl3, 101 MHz) δ 140.12,
138.16, 138.13, 130.10, 129.92, 129.73, 129.22,
128.15, 128.07, 127.86, 127.64, 126.00, 93.52, 80.41,
General Procedure for the Synthesis of 2-Nitro-
1,3,3-triphenylpropyl nitrate (1a)
To an oven-dried 25 mL round bottom flask was
added (E)-prop-2-ene-1,1,3-triyltribenzene (135 mg,
0.5 mmol) and subjected to the vacuum for 10 minutes.
Next, CH3CN (2 mL) and tert-butyl nitrite (0.119 mL,
1.0 mmol) were introduced to the flask through a
syringe under an oxygen atmosphere (balloon). Then
the reaction mixture was stirred at 0 oC for 24 h. After
the completion of the reaction excess solvent was
evacuated under reduced pressure. The reaction
mixture was admixed with dichloromethane (20 mL)
and washed with water (2 x 10 mL) and organic layer
was separated. The separated organic layer was dried
over anhydrous sodium sulphate (Na2SO4), and
evaporated under reduced pressure. The crude product
so obtained was purified by silica gel column
chromatography using hexane as the eluent to give
pure 2-nitro-1,3,3-triphenylpropyl nitrate (1a, 140 mg,
74% yield). The identity and purity of the product was
confirmed by spectroscopic analysis.
52.01, 21.35 ppm. IR (KBr): ν̃ = 3031, 2915, 1653,
1552, 1492, 1450, 1363, 1270, 1087, 1031, 823, 751,
704, 588, 532 cm-1. HRMS (ESI/Q-TOF) m/z: [M +
NH4]+ Calcd for C22H24N3O5 410.1710, Found
410.1739.
2-Nitro-3,3-diphenyl-1-(m-tolyl)propyl
nitrate
(3a): Yellow solid, (128 mg, 65%); m.p. 116119 °C.
1H NMR (400 MHz, CDCl3) δ 7.36 (d, J = 7.5 Hz, 2H),
7.31 (d, J = 4.4 Hz, 4H), 7.28–7.19 (m, 5H), 7.12 (d, J
= 7.6 Hz, 1H), 7.03 (d, J = 7.6 Hz, 1H), 6.97 (s, 1H),
5.84 (d, J = 5.1 Hz, 1H), 5.68 (dd, J = 11.4, 5.1 Hz,
1H), 4.86 (d, J = 11.4 Hz, 1H), 2.29 (s, 3H) ppm. 13C
NMR (CDCl3, 101 MHz) δ 139.14, 138.15, 138.12,
132.86, 130.82, 129.69, 129.21, 128.18, 128.07,
127.84, 127.63, 126.72, 123.06, 93.43, 80.56, 52.13,
7
This article is protected by copyright. All rights reserved.

10.1002/ejoc.202000149
European Journal of Organic Chemistry
21.45 ppm. IR (KBr): ν
̃
= 3031, 2915, 1645, 1556,
707, 674 cm-1. HRMS (ESI/Q-TOF) m/z: [M + NH4]+
Calcd for C21H21ClN3O5 430.1164, Found 430.1180.
1492, 1452, 1364, 1272, 1036, 836, 748, 696, 613 cm-
1. HRMS (ESI/Q-TOF) m/z: [M + NH4]+ Calcd for
C22H24N3O5 410.1710, Found 410.1735.
1-(3-Chlorophenyl)-2-nitro-3,3-diphenylpropyl
nitrate (8a): Yellow solid, (151 mg, 73%); m.p.
116119 °C. 1H NMR (400 MHz, CDCl3) δ 7.36 (d, J
= 7.6 Hz, 2H), 7.32–7.22 (m, 10H), 7.17 (s, 1H), 7.12
(d, J = 7.6 Hz, 1H), 5.83 (d, J = 5.2 Hz, 1H), 5.67 (dd,
J = 11.6, 5.2 Hz, 1H), 4.86 (d, J = 11.6 Hz, 1H) ppm.
13C NMR (CDCl3, 101 MHz) δ 139.14, 138.15,
138.12, 132.86, 130.82, 129.69, 129.21, 128.18,
128.07, 127.84, 127.63, 126.72, 123.06, 93.43, 80.56,
1-(4-(tert-Butyl)phenyl)-2-nitro-3,3-
diphenylpropyl nitrate (4a): Yellow gummy, (135
1
mg, 62%). H NMR (400 MHz, CDCl3) δ 7.35–7.26
(m, 11H), 7.23–7.19 (m, 2H), 7.12 (d, J = 8.0 Hz, 2H),
5.90 (d, J = 5.6 Hz, 1H), 5.69 (dd, J = 11.2, 5.6 Hz,
1H), 4.81 (d, J = 11.2 Hz, 1H), 1.26 (s, 9H) ppm. 13C
NMR (CDCl3, 101 MHz) δ 153.12, 138.23, 138.14,
129.73, 129.62, 129.20, 128.08, 128.05, 127.88,
127.67, 126.19, 93.17, 80.94, 52.40, 31.26 ppm. IR
52.13, 21.45 ppm. IR (KBr): ν̃ = 3029, 2958, 1658,
1554, 1491, 1361, 1275, 1098, 1079, 1032, 820, 787,
747, 696, 614 cm-1. HRMS (ESI/Q-TOF) m/z: [M +
NH4]+ Calcd for C21H21ClN3O5 430.1164, Found
430.1176.
(KBr): ν̃ = 3034, 2961, 1645, 1556, 1493, 1453, 1363,
1272, 1107, 1029, 831, 749, 698, 610 cm-1. HRMS
(ESI/Q-TOF) m/z: [M + NH4]+ Calcd for C25H30N3O5
452.2180, Found 452.2209.
1-(4-Bromophenyl)-2-nitro-3,3-diphenylpropyl
nitrate (9a): Yellow gummy, (171 mg, 75%). H
1
1-([1,1'-Biphenyl]-4-yl)-2-nitro-3,3-diphenylpropyl
nitrate (5a): Yellow gummy, (145 mg, 64%). H
1
NMR (400 MHz, CDCl3) δ 7.45 (d, J = 8.4 Hz, 2H),
7.36–7.26 (m,10H), 7.08 (d, J = 8.4 Hz, 2H), 5.82 (d,
J = 5.2 Hz, 1H), 5.65 (dd, J = 11.6, 5.2 Hz, 1H), 4.85
(d, J = 11.2 Hz, 1H) ppm. 13C NMR (CDCl3, 101 MHz)
δ 137.94, 137.89, 132.57, 129.84, 129.29, 128.31,
128.19, 127.84, 127.78, 127.56, 124.38, 93.24, 79.83,
NMR (600 MHz, CDCl3) δ 7.53–7.50 (m, 3H), 7.43 (t,
J = 7.5 Hz, 2H), 7.37 (d, J = 7.8 Hz, 3H), 7.30–7.27
(m, 9H), 7.25–7.21 (m, 2H), 5.94 (d, J = 5.4 Hz, 1H),
5.74 (dd, J = 11.4, 5.4 Hz, 1H), 4.88 (d, J = 11.4 Hz,
1H) ppm. 13C NMR (151 MHz, CDCl3) δ 142.92,
140.07, 138.10, 138.05, 131.71, 129.72, 129.24,
129.00, 128.13, 128.12, 127.97, 127.88, 127.63,
52.12 ppm. IR (KBr): ν̃ = 3029, 2958, 1658, 1554,
1491, 1361, 1275, 1098, 1079, 1032, 820, 787, 747,
698, 616 cm-1. HRMS (ESI/Q-TOF) m/z: [M + NH4]+
Calcd for C21H21BrN3O5 476.0642, Found 476.0658.
127.25, 126.71, 93.31, 80.56, 52.26 ppm. IR (KBr): ν
= 3035, 2961, 1646, 1556, 1489, 1451, 1362, 1270,
1025, 828, 749, 695 cm-1. HRMS (ESI/Q-TOF) m/z:
̃
[M + NH4]+ Calcd for C27H26N3O5 472.1867, Found
472.1870.
1-(4-Fluorophenyl)-2-nitro-3,3-diphenylpropyl
nitrate (10a): Colourless solid, (153 mg, 77 %); m.p.
128131 °C. 1H NMR (400 MHz, CDCl3) δ 7.35 (d, J
= 7.2 Hz, 2H), 7.31–7.29 (m, 5H), 7.27–7.18 (m, 5H),
7.00 (t, J = 8.6 Hz, 2H), 5.86 (d, J = 5.2 Hz, 1H), 5.66
(dd, J = 11.2, 5.2 Hz, 1H), 4.85 (d, J = 11.2 Hz, 1H)
ppm. 13C NMR (101 MHz, CDCl3) δ 163.49 (d, J =
251.49 Hz), 137.97 (d, J = 5.1 Hz), 129.80, 129.27,
128.87 (d, J = 3.3 Hz), 128.28, 128.20, 128.17, 127.83,
127.57, 116.5 (d, J = 22.2 Hz), 93.39, 79.89, 52.17
ppm. 19F NMR (CDCl3, 377 MHz) δ -110.42. IR
1-(4-(Chloromethyl)phenyl)-2-nitro-3,3-
diphenylpropyl nitrate (6a): Yellow solid, (137 mg,
64%); m.p. 120125 °C. 1H NMR (400 MHz, CDCl3)
δ 7.36–7.33 (m, 4H), 7.31–7.28 (m, 5H), 7.27–7.20
(m, 5H), 5.87 (d, J = 5.2 Hz, 1H), 5.68 (dd, J = 11.6,
5.2 Hz, 1H), 4.87 (d, J = 11.6 Hz, 1H), 4.52 (s, 2H)
13
ppm. C NMR (CDCl3, 101 MHz) δ 140.94, 138.09,
136.14, 136.08, 129.75, 127.72, 127.23, 127.00,
126.12, 125.97, 125.90, 125.65, 125.25, 124.75, 91.33,
(KBr): ν̃ = 3031, 2958, 1654, 1601, 1551, 1508, 1492,
78.61, 50.30, 27.83 ppm. IR (KBr): ν
̃
= 3032, 2960,
1364, 1270, 1228, 1158, 1092, 1031, 825, 752, 703,
674 cm-1. HRMS (ESI/Q-TOF) m/z: [M + NH4]+ Calcd
for C21H21FN3O5 414.1460, Found 414.1480.
1654, 1554, 1492, 1451, 1360, 1275, 1032, 899, 828,
748, 698, 671, 617, 591, 552 cm-1. HRMS (ESI/Q-
TOF) m/z: [M + NH4]+ Calcd for C22H23ClN3O5
444.1321, Found 444.1334.
2-Nitro-1-(3-nitrophenyl)-3,3-diphenylpropyl
1
nitrate (11a): Yellow gummy, (144 mg, 68%). H
1-(4-Chlorophenyl)-2-nitro-3,3-diphenylpropyl
nitrate (7a): Yellow solid, (155 mg, 75%); m.p.
140144 °C. 1H NMR (400 MHz, CDCl3) δ 7.35 (d, J
= 8.0 Hz, 2H), 7.31–7.27 (m, 8H), 7.25–7.22 (m, 2H),
7.14 (d, J = 8.4 Hz, 2H), 5.83 (d, J = 5.2 Hz, 1H), 5.66
(dd, J = 11.6, 5.6 Hz, 1H), 4.86 (d, J = 11.6 Hz, 1H)
ppm. C NMR (101 MHz, CDCl3) δ 137.94, 137.88,
136.15, 131.52, 129.83, 129.61, 129.28, 128.30,
128.18, 127.83, 127.54, 93.29, 79.77, 52.11 ppm. IR
NMR (600 MHz, CDCl3) δ 8.18 (d, J = 8.4 Hz, 1H),
8.05 (s, 1H), 7.60 (d, J = 7.8 Hz, 1H), 7.53 (t, J = 7.8
Hz, 1H), 7.36 (d, J = 7.2 Hz, 2H), 7.32–7.29 (m, 6H),
7.25–7.22 (m, 2H), 5.98 (d, J = 5.4 Hz, 1H), 5.74 (dd,
J = 12.0, 5.4 Hz, 1H), 4.88 (d, J = 11.4 Hz, 1H) ppm.
13C NMR (151 MHz, CDCl3) δ 148.45, 137.72,
137.54, 135.31, 131.80, 130.65, 129.93, 129.36,
128.44, 128.30, 127.81, 127.46, 126.64, 124.91,
13
121.85, 92.94, 79.45, 52.32 ppm. IR (KBr): ν̃ = 3032,
(KBr): ν
̃ = 3029, 2912, 1658, 1598, 1554, 1491, 1452,
2922, 1658, 1554, 1524, 1451, 1349, 1274, 1090,
1410, 1365, 1273, 1196, 1091, 1033, 900, 826, 755,
1031, 825, 736, 700, 592, 551 cm-1. HRMS (ESI/Q-
8
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10.1002/ejoc.202000149
European Journal of Organic Chemistry
TOF) m/z: [M + Na]+ Calcd for C21H17N3NaO7
446.0959, Found 446.0965.
3,3-bis(4-Fluorophenyl)-2-nitro-1-phenylpropyl
nitrate (16a): Yellow solid, (164 mg, 79%); m.p.
130135 °C. 1H NMR (400 MHz, CDCl3) δ 7.347.19
(m, 9H), 7.02–6.96 (m, 4H), 5.89 (d, J = 5.6 Hz, 1H),
5.60 (dd, J = 11.2, 5.6 Hz, 1H), 4.82 (d, J = 11.2 Hz,
1H) ppm. 13C NMR (CDCl3, 101 MHz) δ 162.46 (d, J
= 248.46 Hz), 162.35 (d, J = 249.47 Hz), 133.72 (d, J
= 3.8 Hz), 132.70, 130.22, 129.51, 129.42, 129.41,
129.35, 129.27, 126.33, 116.68 (d, J = 47.47 Hz),
116.45 (d, J = 47.47 Hz), 93.29, 80.63 50.72 ppm. 19F
NMR (377 MHz, CDCl3) δ -113.10, -113.61 IR (KBr):
1-(Naphthalen-2-yl)-2-nitro-3,3-diphenylpropyl
nitrate (12a): Yellow gummy, (122 mg, 57%) H
1
NMR (600 MHz, CDCl3) δ 7.82–7.79 (m, 3H), 7.69 (s,
1H), 7.52–7.50 (m, 2H), 7.37 (d, J = 7.8 Hz, 2H), 7.34
(d, J = 7.2 Hz, 2H), 7.31–7.27 (m, 5H), 7.24–7.19 (m,
2H), 6.04 (d, J = 5.4 Hz, 1H), 5.80 (dd, J = 11.4, 5.4
Hz, 1H), 4.92 (d, J = 11.4 Hz, 1H) ppm. 13C NMR (151
MHz, CDCl3) δ 138.08, 138.06, 133.81, 133.03,
130.22, 129.73, 129.50, 129.25, 128.34, 128.21,
128.12, 127.94, 127.86, 127.64, 127.32, 127.04,
126.11, 122.71, 93.35, 80.64, 52.17 ppm. IR (KBr): ν
= 2921, 2853, 1646, 1555, 1493, 1453, 1364, 1273,
1029, 824, 747, 698 cm-1. HRMS (ESI/Q-TOF) m/z:
[M + Na]+ Calcd for C25H20N2NaO5 451.1264, Found
451.1273.
ν̃ = 3065, 2917, 1661, 1603, 1564, 1508, 1453, 1418,
1366, 1230, 1161, 1109, 1033, 905, 833, 777, 750,
700, 677 cm-1. HRMS (ESI/Q-TOF) m/z: [M + NH4]+
Calcd for C21H20F2N3O5 432.1366, Found 432.1371.
̃
1-(10,10-Dimethyl-9,10-dihydroanthracen-9-yl)-2-
nitro-2-phenylethyl nitrate (17a): Gummy, (155 mg,
1
74%). H NMR (400 MHz, CDCl3) δ 7.60 (dd, J =
2-Nitro-1-phenyl-3,3-di-p-tolylpropyl nitrate (13a):
Yellow gummy, (148 mg, 73%). 1H NMR (400 MHz,
15.2, 8.0 Hz, 2H), 7.44–7.33 (m, 7H), 7.26 (d, J = 4.4
Hz, 3H), 7.18 (d, J = 7.6 Hz, 1H), 6.02 (d, J = 7.2 Hz,
1H), 5.02 (t, J = 6.9 Hz, 1H), 4.72 (d, J = 6.8 Hz, 1H),
1.68 (s, 3H), 1.65 (s, 3H) ppm. 13C NMR (CDCl3, 101
MHz) δ 145.60, 144.86, 132.92, 131.54, 130.57,
130.40, 129.70, 128.70, 128.67, 128.04, 127.99,
127.40, 127.15, 127.08, 126.67, 97.10, 80.83, 45.18,
CDCl3) δ 7.33–7.31 (m, 3H), 7.23–7.18 (m, 6H), 7.11–
7.06 (m, 4H), 5.85 (d, J = 4.8 Hz, 1H), 5.64 (dd, J =
11.6, 4.8 Hz, 1H), 4.82 (d, J = 11.6 Hz, 1H), 2.28 (s,
3H), 2.25 (s, 3H) ppm. 13C NMR (101 MHz, CDCl3) δ
137.96, 137.71, 135.34, 135.31, 133.20, 130.42,
129.87, 129.30, 127.40, 126, 93.74, 80.32, 51.28,
38.87, 35.53, 32.77 ppm. IR (KBr): ν̃ = 3036, 2971,
21.13, 21.11 ppm. IR (KBr): ν̃ = 3030, 2919, 1646,
1656, 1511, 1365, 1273, 1037, 906, 832, 732, 697 cm-
1. HRMS (ESI/Q-TOF) m/z: [M + NH4]+ Calcd for
C23H26N3O5 424.1867, Found 424.1875.
1658, 1599, 1448, 1322, 1264, 1167, 1039, 932, 735,
700 cm-1. HRMS (ESI/Q-TOF) m/z: [M + Na]+ Calcd
for C24H22NaN2O5 441.1421, Found 441.1432.
2-Nitro-1,3-diphenylbutyl nitrate (18a): Gummy,
(79 mg, 50%). H NMR (400 MHz, CDCl3) δ 7.45–
3,3-bis(4-Ethylphenyl)-2-nitro-1-phenylpropyl
nitrate (14a): Yellow gummy, (163 mg, 75%). H
1
1
7.42 (m, 3H), 7.38–7.36 (m, 2H), 7.27–7.25 (m, 3H),
7.01–6.99 (m, 2H), 6.20 (d, J = 9.6 Hz, 1H), 5.11 (dd,
J = 9.6, 6.0 Hz, 1H), 3.27–3.17 (m, 1H), 1.33 (d, J =
7.2 Hz, 3H). ppm. 13C NMR (101 MHz, CDCl3) δ
138.45, 132.29, 130.68, 129.45, 128.78, 128.30,
128.18, 127.84, 92.88, 82.29, 40.17, 18.86 ppm. IR
NMR (400 MHz, CDCl3) δ 7.24–7.21 (m, 3H), 7.18 (d,
J = 8.4 Hz, 2H), 7.44–7.12 (m, 4H), 7.03 (t, J = 8.2 Hz,
4H), 5.79 (d, J = 4.8 Hz, 1H), 5.58 (dd, J = 11.6, 4.8
Hz, 1H), 4.75 (d, J = 11.2 Hz, 1H), 2.53–2.44 (m, 4H),
1.12–1.05 (m, 6H) ppm. 13C NMR (CDCl3, 101 MHz)
δ 144.17, 143.92, 135.57, 135.48, 133.21, 129.89,
129.26, 129.18, 128.64, 127.73, 127.47, 126.08, 93.70,
80.49, 51.48, 28.49, 28.45, 15.41, 15.41 ppm. IR
(KBr): ν̃ = 3037, 2979, 1694, 1640, 1552, 1494, 1452,
1270, 1199, 1084, 1040, 745, 695 cm-1. HRMS
(ESI/Q-TOF) m/z: [M + Na]+ Calcd for C16H16NaN2O5
339.0951, Found 339.0959.
(KBr): ν̃ = 3031, 2966, 1646, 1557, 1510, 1455, 1365,
1273, 1125, 1034, 905, 829, 744, 696 cm-1. HRMS
(ESI/Q-TOF) m/z: [M + NH4]+ Calcd for C25H30N3O5
452.2180, Found 452.2192.
1,3-bis(4-Bromophenyl)-2-nitrobutyl nitrate (19a):
o
1
Yellow solid, m.p. 183187 C, (135 mg, 57%). H
NMR (600 MHz, CDCl3) δ 7.52 (d, J = 8.4 Hz, 2H),
7.35 (d, J = 8.4 Hz, 2H), 7.15 (d, J = 8.4 Hz, 2H), 6.79
(d, J = 8.4 Hz, 2H), 6.05 (d, J = 9.0 Hz, 1H), 4.96 (dd,
J = 9.0, 6.0 Hz, 1H), 3.17–3.11 (m, 1H), 1.28 (d, J =
7.2 Hz, 3H) ppm. 13C NMR (151 MHz, CDCl3) δ
137.27, 132.86, 132.11, 131.20, 129.81, 129.53,
125.32, 122.43, 92.44, 81.16, 39.74, 18.61 ppm. IR
3,3-bis(4-Chlorophenyl)-2-nitro-1-phenylpropyl
nitrate (15a): Yellow gummy, (171 mg, 77%). H
1
NMR (400 MHz, CDCl3) δ 7.33 (d, J = 8.0 Hz, 3H),
7.28–7.25 (m, 6H), 7.22–7.17 (m, 4H), 5.89 (d, J = 5.6
Hz, 1H), 5.60 (dd, J = 10.8, 5.6 Hz, 1H), 4.79 (d, J =
11.2 Hz, 1H) ppm. 13C NMR (101 MHz, CDCl3) δ
136.15, 136.05, 134.45, 134.41, 132.59, 130.26,
129.99, 129.58, 129.43, 129.11, 128.95, 126.34, 92.83,
(KBr): ν̃ = 3049, 2925, 2854, 1644, 1555, 1460, 1375,
1274, 1016, 801, 723 cm-1. HRMS (ESI/Q-TOF) m/z:
[M + NH4]+ Calcd for C16H18Br2N3O5 491.9588,
Found 491.9595.
80.62, 50.95.ppm. IR (KBr): ν̃ = 3030, 2916, 1900,
1654, 1648, 1557, 1490, 1410, 1364, 1273, 1091,
1013, 906, 819, 730, 696 cm-1. HRMS (ESI/Q-TOF)
m/z: [M + NH4]+ Calcd for C21H20Cl2N3O5 464.0775,
Found 464.0782.
1,3-bis(4-Chlorophenyl)-2-nitrobutyl nitrate (20a):
Gummy, (100 mg, 52 %). 1H NMR (600 MHz, CDCl3)
9
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10.1002/ejoc.202000149
European Journal of Organic Chemistry
δ 7.45 (d, J = 6.6 Hz, 2H), 7.39–7.37 (m, 2H), 7.28–
7.25 (m, 2H), 7.00–6.98 (m, 2H), 6.19 (d, J = 9.6 Hz,
1H), 5.10 (dd, J = 9.0, 5.4 Hz, 1H), 3.23–3.19 (m, 1H),
1.36 (d, J = 7.2 Hz, 3H) ppm. 13C NMR (151 MHz,
CDCl3) δ 138.44, 132.39, 130.74, 129.51, 128.85,
128.40, 128.27, 127.90, 92.88, 82.28, 40.22, 18.99
Calcd for C8H6BrNaNO2 [M + Na]+ 249.9474, Found
249.9480.
(E)-1-Fluoro-4-(2-nitrovinyl)benzene (26a): Yellow
solid, (59 mg, 71%); m.p. 102105 °C. 1H NMR (400
MHz, CDCl3) δ 7.99 (d, J = 13.7 Hz, 1H), 7.59–7.52
(m, 3H), 7.16 (t, J = 8.6 Hz, 2H) ppm. 13C NMR (101
MHz, CDCl3) δ 165.06 (d, J = 255.83 Hz), 137.96,
136.99, 131.41 (d, J = 8.9 Hz), 126.46, 116.91 (d, J =
22.32 Hz) ppm. 19F NMR (377 MHz, CDCl3) δ -
ppm. IR (KBr): ν
1449, 1366, 1275, 1092, 1014, 749 cm-1. HRMS
(ESI/Q-TOF) m/z: [M
NH4]+ Calcd for
̃ = 3036, 2924, 2848, 1653, 1558,
+
C16H18Cl2N3O5 402.0618, Found 402.0625.
105.81. IR (KBr): ν̃ = 3109, 2973, 1630, 1554, 1514,
1449, 1338, 1261, 1189, 1072, 964, 762, 699 cm-1.
HRMS (ESI/Q-TOF) m/z: Calcd for C8H6FNaNO2 [M
+ Na]+ 190.0275, Found 190.0287.
(E)-(2-Nitrovinyl)benzene (21a): Yellow solid, (49
mg, 67%), m.p. 5761 °C.1H NMR (600 MHz, CDCl3)
δ 8.01 (d, J = 13.7 Hz, 1H), 7.59 (d, J = 13.7 Hz, 1H),
7.56–7.54 (m, 2H), 7.52–7.49 (m, 1H), 7.47–7.44 (m,
2H) ppm. 13C NMR (151 MHz, CDCl3) δ 139.21,
137.24, 132.27, 130.19, 129.52, 129.27 ppm. IR
(E)-1-Chloro-2-nitro-4-(2-nitrovinyl)benzene
(27a): Yellow solid, (87 mg, 76%); m.p. 131135 °C.
1H NMR (600 MHz, CDCl3 +DMSO-d6) δ 8.33 (d, J =
6.0 Hz, 1H), 8.10–7.96 (m, 2H), 7.93–7.83 (m, 1H),
7.73–7.61 (m, 1H) ppm. 13C NMR (151 MHz, CDCl3
+ DMSO-d6) δ 147.68, 139.39, 134.85, 132.77,
(KBr): ν̃ = 3109, 2923, 1632, 1577, 1513, 1449, 1344,
1262, 967, 764, 750 cm-1. HRMS (ESI/Q-TOF) Calcd
for C8H7NaNO2 [M + Na]+ 172.0369, Found 172.0382.
132.10, 129.96, 128.80, 125.34 ppm. IR (KBr): ν̃ =
(E)-1-Methyl-4-(2-nitrovinyl)benzene
(22a):
3103, 3039, 2924, 2852, 1734, 1633, 1591, 1518,
1404, 1339, 1259, 1086, 970, 819, 742 cm-1. HRMS
(ESI/Q-TOF) m/z: Calcd for C8H5ClNaN2O4 [M +
Na]+ 250.983, Found 250.989.
1
Yellow solid, (51 mg, 63%); m.p. 106109 °C. H
NMR (400 MHz, CDCl3) δ 7.99 (d, J = 13.6 Hz, 1H),
7.57 (d, J = 13.7 Hz, 1H), 7.45 (d, J = 8.4 Hz, 2H),
7.26 (d, J = 7.6 Hz, 2H), 2.41 (s, 3H) ppm. 13C NMR
(101 MHz, CDCl3) δ 143.24, 139.30, 136.42, 130.28 ,
(E)-1,3,5-Trimethyl-2-(2-nitrovinyl)benzene (28a):
1
Yellow solid, (56 mg, 59%); m.p.  °C. H
129.32, 127.41, 21.79 ppm. IR (KBr): ν̃ = 3109, 2923,
2853, 1632, 1496, 1341, 1265, 965, 810, 741 cm-1.
HRMS ESI/Q-TOF) m/z: Calcd for C9H10NO2 [M +
H]+ 164.0706, found 164.0712.
NMR (400 MHz, CDCl3) δ 8.27 (d, J = 13.9 Hz, 1H),
7.31 (d, J = 13.9 Hz, 1H), 6.95 (s, 2H), 2.39 (s, 6H),
2.31 (s, 3H) ppm. 13C NMR (101 MHz, CDCl3) δ
141.01, 139.82, 138.61, 136.72, 130.02, 125.88, 21.67,
(E)-1-Methoxy-4-(2-nitrovinyl)benzene
(23a):
21.34 ppm. IR (KBr): ν̃ = 2918, 1627, 1604, 1500,
Yellow solid, (55 mg, 61%); m.p. 8588 °C. 1H NMR
(600 MHz, CDCl3) δ 7.97 (d, J = 13.6 Hz, 1H), 7.54–
7.48 (m, 3H), 6.96 (d, J = 8.8 Hz, 2H), 3.87 (s, 3H)
1329, 1149, 1032, 967, 922, 799, 751, 716 cm-1.
HRMS (ESI/Q-TOF) m/z: Calcd for C11H13NaNO2 [M
+ Na]+ 214.0838, Found 214.0847.
13
ppm. C NMR (151 MHz, CDCl3) δ 163.03, 139.18,
135.07, 131.29, 122.60, 115.01, 55.64 ppm. IR (KBr):
(E)-2-(2-Nitrovinyl)naphthalene (29a): Yellow
solid, (57 mg, 57%); m.p. 129132 °C. 1H NMR (400
MHz, CDCl3) δ 8.14 (d, J = 13.6 Hz, 1H), 7.99 (s, 1H),
7.89–7.85 (m, 3H), 7.68 (d, J = 13.6 Hz, 1H), 7.63–
7.53 (m, 3H) ppm. 13C NMR (101 MHz, CDCl3) δ
139.34, 137.25, 135.03, 133.26, 132.39, 129.48,
128.95, 128.51, 128.06, 127.66, 127.40, 123.44 ppm.
ν̃ = 2925, 1605, 1498, 1339, 1256, 1176, 1031, 973,
809 cm-1. HRMS (ESI/Q-TOF) m/z: Calcd for
C9H10NO3 [M + H]+ 180.0655, Found 180.0669.
(E)-1-Chloro-4-(2-nitrovinyl)benzene
(24a):
1
Yellow solid, (62 mg, 68%), m.p. 102105 °C. H
NMR (400 MHz, CDCl3) δ 7.97 (d, J = 13.7 Hz, 1H),
7.57 (d, J = 14.0 Hz, 1H), 7.50 (d, J = 8.8 Hz, 2H),
7.44 (d, J = 8.8 Hz, 2H) ppm. 13C NMR (151 MHz,
CDCl3) δ 138.46, 137.85, 137.52, 130.40, 129.89,
IR (KBr): ν̃ = 3106, 1625, 1503, 1328, 1267, 1169,
960, 872, 821, 750, 710 cm-1. HRMS (ESI/Q-TOF)
m/z: Calcd for C12H9NaNO2 [M + Na]+ 222.0525,
Found 222.0531.
128.63 ppm. IR (KBr): ν̃ = 3107, 2924, 2852, 1721,
1642, 1601, 1529, 1344, 1201, 1048, 965, 832, 753,
677 cm-1. HRMS (ESI/Q-TOF) m/z: calcd for
C8H6ClNaNO2 [M + Na]+ 205.9979, Found 205.9991.
(E)-1-Bromo-4-(2-nitrovinyl)benzene (25a): Yellow
solid, (80 mg, 70%); m.p. 151154 °C. 1H NMR (400
MHz, CDCl3) δ 7.95 (d, J = 13.7 Hz, 2H), 7.61–7.56
(m, 3H), 7.42 (d, J = 8.4 Hz, 2H) ppm. 13C NMR (151
MHz, CDCl3) δ 137.93, 137.58, 132.87, 130.52,
Acknowledgements
B. K. P acknowledges the support of this research by
the Department of Science and Technology
(DST/SERB) (EMR/2016/007042), CSIR (0333/NS-
EMRII) and MHRD: 5-5/2014-TS-VII (SB/S1/OC-
53/2013), New Delhi and CIF for instrumental
facilities.
129.06, 126.92 ppm. IR (KBr): ν
̃ = 2923, 2849, 1633,
1517, 1341, 1073, 812 cm-1. HRMS (ESI/Q-TOF) m/z:
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10.1002/ejoc.202000149
European Journal of Organic Chemistry
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12
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