Simple Synthesis of Dimethyl Nitrobenzhydrylphosphonates and Heteroarylnitroarylacetonitriles via Vicarious Nucleophilic Substitution (VNS) Reaction

Article abstract of DOI:10.1055/s-0040-1707230

Acetals of dimethyl phenyl- and heteroaryl-α-hydroxymethanephosphonates were deprotonated to generate carbanions, which enter the vicarious nucleophilic substitution (VNS) of hydrogen in aromatic nitro compounds to form 4-nitrobenzhydrylphosphonates and α

Full text of DOI:10.1055/s-0040-1707230

SYNTHESIS
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© Georg Thieme Verlag Stuttgart · New York
2020, 52, A–G
paper
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M. Mąkosza et al.
Paper
Synthesis
Simple Synthesis of Dimethyl Nitrobenzhydrylphosphonates and
Heteroarylnitroarylacetonitriles via Vicarious Nucleophilic
Substitution (VNS) Reaction
Mieczysław Mąkosza*
Małgorzata Bechcicka
Krzysztof Wojciechowski
OEt
Ar
Y
Me
O
Y
1) B–
2) H+
Me
H
Ar
t-BuOK/DMF
Z
O
OEt
Z
+
30–85%
Z
Institute of Organic Chemistry Polish Academy of
Sciences, ul. Kasprzaka 44/52, 01-224 Warszawa,
Poland
Ar
Y
NO2
18 examples
NO2
N
Ar = Ph, 2-furyl,
2-thienyl
Y = PO(OMe)2, CN
Z = H, 2-Cl, 3-Cl, 2-I
1-nitronaphthalene
5-nitroquinoline
O
O
icho-s@icho.edu.pl
Received: 28.05.2020
Accepted after revision: 30.06.2020
Published online: 25.08.2020
Dialkyl benzyl- and benzhydrylphosphonates are wide-
ly used in agrochemistry and pharmacy, since development
of simple synthesis of this class of compounds is of great in-
terest.6
DOI: 10.1055/s-0040-1707230; Art ID: ss-2020-t0292-op
Abstract Acetals of dimethyl phenyl- and heteroaryl--hydroxymetha-
nephosphonates were deprotonated to generate carbanions, which en-
ter the vicarious nucleophilic substitution (VNS) of hydrogen in aromat-
ic nitro compounds to form 4-nitrobenzhydrylphosphonates and -
heteroaryl-4-nitrobenzylphosphonates. Similarly acetals of cyano-
hydrins of heteroaromatic aldehydes (furfural and 2-formylthiophene)
react to form heteroaryl 4-nitroarylacetonitriles. The anion of the hemi-
acetal of acetaldehyde is an efficient leaving group in the base-induced
-elimination step – the crucial step in the VNS reaction. The reaction
selectively occurred at the para-position to the nitro group.
There are a few ways of synthesis of dialkyl benzhydryl-
phosphonates: typical Michaelis–Becker and Arbuzov reac-
tions of benzhydryl halides with dialkyl or trialkyl phos-
phites,7 Friedel–Crafts type reaction of -chlorobenzyl-
phosphonates,8 and Pd-catalyzed nucleophilic substitution
of bromide in bromobenzenes by dialkyl benzylphospho-
nate carbanions.9 Earlier we have reported VNS in nitroben-
zenes by carbanion of dialkyl -chlorobenzylphosphonates2
that was confirmed in other laboratories10 and oxidative
substitution (ONSH) in nitrobenzenes by carbanion of di-
alkylbenzylphosphonate.11 Both of these reactions gave di-
alkyl nitrobenzhydrylphosphonates.
Key words arylmethanephosphonates, arylacetonitriles, carbanions,
nitroarenes, acetals, vicarious nucleophilic substitution
Vicarious nucleophilic substitution (VNS) of hydrogen is
presently a well-established method of introduction of
carbon, nitrogen, and oxygen substituents into electron-
deficient aromatic rings, particularly nitroarenes.1 The
most important and widely used variant of this process
consists in the addition of -chlorocarbanions to nitroaro-
matic rings to the ortho- and/or para-positions occupied by
hydrogens.2,3 Subsequent base-induced -elimination of
HCl from the formed H-adduct gives products in the form
of nitrobenzylic carbanions isolated upon protonation.
Since -chlorocarbanions are very unstable it was shown
that carbanions containing some other leaving groups such
as methoxy, phenoxy, phenylthio, N,N-dialkyldithiocarbam-
oyl are in some cases more convenient starting materials in
the VNS reaction.4,5 VNS is an efficient tool for replacement
of hydrogen in aromatic rings with carbon substituents,
hence can be considered as an umpolung and complemen-
tary to the Friedel–Crafts reaction that cannot be applied to
nitroarenes (Scheme 1).
In 2019, an interesting paper describing synthesis of di-
arylmethanephosphonates via BF3-catalyzed reactions of
trimethylsilyl-protected diethyl -hydroxybenzyl phospho-
nates, generated in situ from aromatic aldehydes and tri-
ethyl phosphite with electron-rich arenes was published by
Korean chemists.12 This reaction is a classic example of the
Friedel–Crafts reaction.
R
Y
X
X
B–
R
Y
R
Y
R
Y
H
B–
H+
R
X
–
+
Y
Z
Z
Z
Z
– HX
NO2–
NO2
and/or ortho-isomers
NO2
NO2
X = Cl, MeO, PhO, PhS, R2NCS2
Y = CN, CO2R, SO2Ph, etc.
R = H, alkyl, aryl
Z = Cl, Br, I, OMe, CF3, CN, CO2R, etc.
Scheme 1 General scheme of the VNS reaction
© 2020. Thieme. All rights reserved. Synthesis 2020, 52, A–G
Georg Thieme Verlag KG, Rüdigerstraße 14, 70469 Stuttgart, Germany

B
M. Mąkosza et al.
Paper
Synthesis
Similarly, diarylacetonitriles are versatile intermediates
in organic synthesis, particularly as pharmaceuticals and
plant protection agents. They are usually synthesized via
Friedel–Crafts reaction of -cyanobenzylic electrophiles
with arenes,13 reactions of benzhydrylic halides with cya-
nide sources,14 transition-metal-catalyzed reactions of aryl
bromides with arylacetonitriles carbanions,15 or SNAr sub-
stitution of halogen in ortho- and para-halonitroarenes by
phenylacetonitrile carbanions.16 Surprisingly, arylhet-
eroarylacetonitriles are scarcely mentioned in literature.
Phenylpyridyl17 and phenylquinazolyl18 acetonitriles were
obtained via substitution of bromine in these azine rings by
reaction with phenylacetonitrile carbanion. A series of di-
heteroarylacetonitriles have been obtained via reductive
transformation of 1,1-diheteroaryl-2-nitroethanes.19 On
the other hand arylfuryl and arylthienylacetonitriles were
not described. Some years ago we have reported that nitro-
diarylacetonitriles are efficiently synthesized via VNS reac-
tion of carbanions of -methoxy- and -phenoxypheny-
lacetonitriles with nitroarenes.5 Recently, we have present-
ed a simple synthesis of p-nitrodiarylacetonitriles via VNS
reaction of carbanions generated from readily available cy-
anohydrins of aromatic aldehydes protected in the form of
acetals in the reaction with ethyl vinyl ether.20 Observation
that a hemiacetal group can be eliminated in base-induced
-elimination prompted us to attempt VNS reaction in ni-
troarenes by carbanions of readily available dimethyl -hy-
droxybenzylphosphonates O-protected in a form of acetals
and expand this approach to the synthesis of heteroaryl-
nitroarylacetonitriles.
tion of equimolar amounts of phosphonate 1 and nitro-
benzene (4a) in DMF to t-BuOK (3 molar excess ) in DMF at
–10 °C resulted in an intense purple coloration of the reac-
tion mixture. After stirring for 30 minutes, the reaction
mixture was quenched with acidified water and the prod-
uct was isolated and purified by column chromatography.
The expected product dimethyl 4-nitrobenzhydrylphos-
phonate (1a) was isolated in 62% yield. Under similar condi-
tions the phosphonates 2 and 3 were reacted with ni-
troarenes to give expected esters of diarylmethylphosphon-
ic acids 1a–3e. The products are presented in Scheme 3.
OEt
Ar
PO(OMe)2
1) B–
2) H+
Me
O
PO(OMe)2
Ar
Me
t-BuOK/DMF
H
O
Z
Z
+
Ar
OEt
PO(OMe)2
1, Ar = Ph
2, Ar = 2-furyl
Z
NO2
4a, Z = H
NO2
1a–3e
N
3, Ar = 2-thienyl 4b, Z = 2-Cl
4c, Z = 3-Cl
O
O
4d, 1-nitronaphthalene
4e, 5-nitroquinoline
NO2
NO2
Cl
NO2
PO(OMe)2
1a (62%)
PO(OMe)2
PO(OMe)2
1d (45%)
1b (55%)
NO2
NO2
Cl
NO2
O
PO(OMe)2
NO2
O
S
PO(OMe)2
PO(OMe)2
2a (64%)
3a (62%)
2b (53%)
NO2
NO2
The starting dimethyl aryl--hydroxymethanephospho-
nates were obtained via base-catalyzed addition of dimeth-
yl phosphite to benzaldehyde, furfural, and 2-formylthio-
phene following the known procedure.21 Protection of the
hydroxy group in these hydroxyarylmethylphosphonates in
the reaction with ethyl vinyl ether was not reported in the
literature. We have found that this protection proceeds
smoothly upon treatment of these -hydroxyphosphonates
and ethyl vinyl ether in diethyl ether catalyzed by dichloro-
acetic acid (Scheme 2). Desired protected phosphonates 1–
3 were purified by column chromatography and were ob-
tained in good yields as mixtures of two diastereoisomers.
Cl
N
Cl
S
S
S
PO(OMe)2
PO(OMe)2
PO(OMe)2
3e (42%)
3b (53%)
3c (39%)
Scheme 3 Synthesis of aryl/heteroarylmethanephosphonates
Yields of the nitroarylheteroarylmethane phosphonates
1a–3e are only moderate because in cases of every reac-
tions some amounts of unidentified and tarry materials
were formed. The lower yields are probably due to a steric
hindrance in the H-adduct caused by the bulky carbanions
of 1–3.
Cyanohydrins of furfural and 2-formylthiophene were
prepared by the reaction of the aldehydes with sodium cya-
nide in the presence of NaHSO3 following the known proce-
dure.22 Protection of these cyanohydrins in the reaction
with ethyl vinyl ether was not reported. Acetal of the furfu-
ral cyanohydrin 5 was synthesized via reaction of the cy-
anohydrin with ethyl vinyl ether catalyzed by dichloroace-
tic acid. In the same manner, acetal 6 of the cyanohydrin of
2-formylthiophene was prepared (Scheme 4). The protect-
ed cyanohydrins of furfural 5 and 2-formylthiophene 6
were purified by column chromatography and obtained as a
mixture of two diastereoisomers in about a 1:1 ratio.
Et
Me
O
HOP(OMe)2
Et3N
O
OH
CHCl2CO2H (cat)
Ar
OEt
ArCHO
Ar
PO(OMe)2
PO(OMe)2
1, Ar = Ph
2, Ar = 2-furyl
3, Ar = 2-thienyl
Scheme 2 Synthesis of protected of -hydroxyarylmethanephospho-
nates
The first experiments of the VNS reaction of phospho-
nate 1 with nitrobenzene (4a) were carried out under con-
ditions commonly used for this reaction. Addition of a solu-
© 2020. Thieme. All rights reserved. Synthesis 2020, 52, A–G

C
M. Mąkosza et al.
Paper
Synthesis
enter the VNS reaction with nitroarenes to give dimethyl
nitrobenzhydrylphosphonates and -heteroaryl-4-nitro-
benzyl phosphonates as the final products. The presented
results offer a general and versatile way to dimethyl nitro-
benzhydryl- and -(nitroaryl)--(heteroaryl)methanephos-
phonates. Similarly, deprotonation of protected cyanohy-
drins of heterocyclic aldehydes followed by the VNS reac-
tion of the generated carbanions with nitroarenes produced
heteroarylnitroarylacetonitriles. These results and that re-
ported earlier20 can be considered analogous and comple-
mentary to the recently reported12,23 introduction of such
substituents into electron-rich arenes via Friedel–Crafts re-
action (Scheme 6). Complementary because they offer pos-
sibility of introduction of -phosphorylbenzyl and -cya-
nobenzyl substituents into electron-deficient nitroaromatic
rings that is not possible via Friedel–Crafts reaction.
Me
OEt
KCN/NaHSO3
Et
O
OH
O
CHO
X
X
CHCl2CO2H cat
X
CN
CN
5, X = O
6, X = S
Scheme 4 Synthesis of cyanohydrin acetals
The preliminary reaction of 5 with nitrobenzene (4a)
was carried out under the conditions commonly used for
the VNS reaction by the addition of equimolar mixture of
the reagents dissolved in DMF to a solution of potassium
tert-butoxide (three molar excess) in DMF at –10 °C. The ad-
dition resulted in strong red-violet (purple) coloration of
the mixture characteristic for para-nitrobenzyl carbanions.
After stirring for 30 minutes, the mixture was poured into
dilute HCl, and the product was isolated and purified by col-
umn chromatography. The expected fur-2-yl-(4-nitrophe-
nyl)acetonitrile (5a) was obtained in a good yield of 82%.
Since bulky sterically demanding carbanion of 5 does not
add at the ortho-position in relation to the nitro group the
substitution proceeds selectively at the para-position, so no
isomers are formed. The mechanism of this reaction consist
in the formation of the H-adduct that undergoes base-in-
duced elimination of acetaldehyde hemiacetal to form car-
banion of the final product. Under similar conditions 6 was
reacted with a variety of substituted nitroarenes 4. Due to
bulkiness of this carbanion only nitroarenes unsubstituted
in the para-position to the nitro group entered the VNS re-
action with 5 and 6. Under similar conditions VNS reaction
of thienyl derivative 6 with nitroarenes was performed.
Also in this case the bulky carbanion entered the substitu-
tion selectively in the para-position to the nitro group giv-
ing (p-nitroaryl)thien-2-ylacetonitriles 6a–d,f. The results
of these experiments are shown in Scheme 5. The het-
eroarylnitroarylacetonitriles are obtained via the VNS reac-
tion of the protected cyanohydrins in good yields.
OEt
Me
O
CN
1) B–
2) H+
NC
X
t-BuOK/DMF
H
5, 6
Z
+
X
Z
Z
NO2
4a, Z = H
4b, Z = 2-Cl
4c, Z = 3-Cl
4d, 1-nitronaphthalene
4f, Z = 2-I
N
NO2
O
O
5a–6f
NO2
NO2
NO2
Cl
O
O
O
Cl
CN
CN
CN
5a (82%)
5b (73%)
5c (50%)
NO2
Cl
NO2
NO2
S
O
S
CN
CN
CN
CN
5d (80%)
6a (77%)
6b (85%)
NO2
NO2
I
NO2
S
S
S
Cl
CN
6d (30%)
CN
In conclusion, we have shown that readily available ac-
etals of -hydroxybenzylphosphonates are deprotonated
upon action of a strong base and the produced carbanions
6c (50%)
6f (46%)
Scheme 5 Synthesis of heteroarylnitroarylacetonitriles
Ar
Ar
Y
Y
H
BF3
– H+
OSiMe3
Y
EDG
Ar
Ar CH
Y
EDG
EDG
EtO
OH
Y
Ar
EtO
Ar
Y
O
Me
1.
–
H
Me
Me
Me
OEt
HO
2. H+
H
Y
O
Y
t-BuOK
O
Y
NO2
Ar
OEt
Ar
NO2
NO2
Y = CN, PO(OR)2
Scheme 6 Similarity and umpolung of the VNS and Friedel–Crafts reactions
© 2020. Thieme. All rights reserved. Synthesis 2020, 52, A–G

D
M. Mąkosza et al.
Paper
Synthesis
31P NMR (202 MHz, CDCl3):  = 25.10.
IR spectra were recorded on JASCO FT/IR-6200 in KBr or film after
evaporation from CH2Cl2. 1H and 13C NMR spectra were recorded on a
Bruker Avance 500 or Varian VNMR S500 (both 500 MHz for H and
MS (EI): m/z (%) = 357 (M+ + 2, 23), 355 (M+, 38), 325 (7), 309 (9), 248
(43), 247 (28), 246 (100), 232 (10), 230 (25), 200 (33), 199 (26), 181
(20), 165 (69), 164 (22), 163 (26), 153 (24), 139 (10), 165 (69), 164
(22), 163 (27), 153 (24), 139 (10), 115 (12), 111 (13), 109 (29).
1
125 MHz for 13C spectra) instruments at 298 K. Chemical shifts are
expressed in parts per million (ppm) referred to TMS, coupling con-
stants in hertz (Hz). Electron impact mass spectra (EI, 70 eV) were ob-
tained on AutoSpec Premier spectrometer. Electrospray mass spectra
(ESI) were obtained on 4000 Q-TRAP and SYNAPT G2-S HDMS. Silica
gel (Merck 60, 230–400 mesh) was used for column chromatography
(CC). Hexane/EtOAc mixtures were used for elution. TLC analyses
were performed on Merck Kieselgel 60 F254 Alufolien with hex-
ane/EtOAc mixtures. All reagents and solvents were of reagent grade
or purified according to standard methods before use. All reactions
were run under argon atmosphere. The starting dimethyl aryl--hy-
droxymethanephosphonates were obtained via base-catalyzed addi-
tion of dimethyl phosphite to benzaldehyde, furfural and 2-formylth-
iophene following the known procedure.21 The synthesis of phospho-
nates 1–3 is described in the Supporting Information. Cyanohydrins
of furfural and 2-formylthiophene were prepared following the
known procedure.22
HRMS (EI): m/z calcd for C15H15ClNO5P: 355.0376; found: 355.0373.
Dimethyl (4-Nitronaphth-1-yl)phenylmethanephosphonate (1d)
Yield: 167 mg (45%); brown semi-solid.
1H NMR (500 MHz, CDCl3):  = 3.58 (d, J = 10.8 Hz, 3 H), 3.60 (d, J =
10.8 Hz, 3 H), 5.32 (d, J = 26.4 Hz, 1 H), 7.24–7.28 (m, 1 H), 7.30–7.35
(m, 2 H), 7.49–7.53 (m, 2 H), 7.60–7.70 (m, 2 H), 8.18 (d, J = 9.8 Hz, 1
H), 8.20 (d, J = 8.6 Hz, 1 H), 8.38 (dd, J = 7.8, 2.0 Hz, 1 H), 8.51 (br d, J =
9.0 Hz, 1 H).
13C NMR (125 MHz, CDCl3):  = 46.13 (d, J = 140 Hz), 53.36 (d, J = 7.6
Hz), 53.97 (d, J = 7.4 Hz), 122.96 (d, J = 1.5 Hz), 123.70, 123.86, 125.64,
126.06 (d, J = 6.6 Hz), 127.82 (d, J = 2.7 Hz), 127.91, 128.81, 128.92 (d,
J = 2.0 Hz), 129.51 (d, J = 6.9 Hz), 132.37 (d, J = 11.5 Hz), 135.01 (d, J =
6.6 Hz), 139.43 (d, J = 2.7 Hz), 146.54 (d, J = 1.5 Hz).
31P NMR (202 MHz, CDCl3):  = 26.62.
MS (EI): m/z (%) = 371 (M+, 46), 325 (8), 263 (31), 262 (100), 261 (22),
VNS Reaction; General Procedure
To a stirred solution of t-BuOK (3.5 mmol) in DMF (9 mL) that was
cooled to –10 °C under an inert atmosphere was added a solution of
nitroarene 4 (1 mmol) and phosphonate 1–3 or nitrile 5,6 (1 mmol) in
DMF (1 mL). The resulting mixture turned a deep violet and was
stirred for 30 min at this temperature. Then it was poured into a 2%
solution of HCl (20 mL), and the mixture was extracted with EtOAc.
The combined organic extracts were dried, concentrated, and the
product was purified by column chromatography (hexane/EtOAc).
245 (27), 231 (26), 216 (67), 215 (87), 203 (22).
HRMS (EI): m/z calcd for C19H18NO5P: 371.0923; found: 371.0920.
Dimethyl (Fur-2-yl)(4-nitrophenyl)methanephosphonate (2a)
Yield: 199 mg (64%); pale brown semisolid.
1H NMR (500 MHz, CD2Cl2):  = 3.62 (d, J = 10.6 Hz, 3 H), 3.68 (d, J =
11.0 Hz, 3 H), 4.73 (d, J = 26.2 Hz, 1 H), 6.43 (dd, J = 2.7, 2.0 Hz, 1 H),
6.53 (dd, J = 2.7, 2.6 Hz, 1 H), 7.44 (br s, 1 H), 7.62–7.66 (m, 2 H), 8.17–
8.22 (m, 2 H).
13C NMR (125 MHz, CD2Cl2):  = 44.74 (d, J = 130 Hz), 53.48 (d, J = 7.0
Hz), 53.70 (d, J = 6.9 Hz), 109.85 (d, J = 5.2 Hz), 111.20 (d, J = 1.6 Hz),
123.99 (d, J = 2.6 Hz), 130.67 (d, J = 6.2 Hz), 142.36 (d, J = 6.2 Hz),
143.15 (d, J = 2.3 Hz), 147.74 (d, J = 2.6 Hz), 148.52 (d, J = 3.8 Hz).
Dimethyl 4-Nitrobenzhydrylphosphonate (1a)
Yield: 198 mg (62%); brownish solid; mp 49–51 °C.
IR (KBr): 2954, 1596, 1520, 1493, 1453, 1348, 1254, 1183, 1111, 1054,
1030, 890, 868, 823, 750, 705, 564 cm–1
.
1H NMR (500 MHz, CDCl3):  = 3.56 (d, J = 10.7 Hz, 3 H), 3.62 (d, J =
10.8 Hz, 3 H), 4.56 (d, J = 25.1 Hz, 1 H), 7.26–7.40 (m, 3 H), 7.47–7.53
(m, 2 H), 7.67–7.73 (m, 2 H), 8.15–8.20 (m, 2 H).
13C NMR (125 MHz, CDCl3):  = 50.65 (d, J = 140 Hz), 53.30 (d, J = 7.0
Hz), 53.88 (d, J = 7.0 Hz), 123.80 (d, J = 1.5 Hz), 127.90 (d, J = 2.0 Hz),
129.03 (d, J = 1.2 Hz), 129.38 (d, J = 8.0 Hz), 130.26 (d, J = 7.9 Hz),
135.05 (d, J = 5.6 Hz), 144.19 (d, J = 5.2 Hz), 147.10.
31P NMR (202 MHz, CDCl3):  = 19.48.
MS (EI): m/z (%) = 311 (M+, 23), 203 (22), 202 (100), 186 (12), 172 (7),
156 (32), 128 (19), 127 (100), 109 (13).
HRMS (EI): m/z calcd for C13H14NO6P: 311.0559; found: 311.0560.
Dimethyl (3-Chloro-4-nitrophenyl)(fur-2-yl)methanephospho-
nate (2b)
31P NMR (202 MHz, CDCl3):  = 25.67.
MS (EI): m/z (%) = 321 (M+, 31), 275 (11), 213 (26), 212 (100), 196
Yield: 184 mg (53%); pale brown semisolid.
(18), 166 (40), 165 (53), 143 (13), 139 (8), 115 (7), 109 (16).
IR (film): 2956, 2854, 1639, 1584, 1529, 1475, 1353, 1254, 1184,
HRMS (EI): m/z calcd for C15H16NO5P: 321.0766; found: 321.0769.
1033, 829, 743, 600 cm–1
.
1H NMR (500 MHz, CDCl3):  = 3.67 (d, J = 10.7 Hz, 3 H), 3.69 (d, J =
10.8 Hz, 1 H), 4.62 (d, J = 26.1 Hz, 1 H), 6.40 (m, 1 H), 5.52 (m, 1 H),
7.50 (ddd, J = 8.6, 1.9, 1.9 Hz, 1 H), 7.61 (dd, J = 1.9, 1.9 Hz, 1 H), 7.85
(d, J = 8.6 Hz, 1 H).
13C NMR (125 MHz, CDCl3):  = 44.21 (d, J = 143 Hz), 53.59 (d, J = 7.2
Hz), 54.03 (d, J = 6.6 Hz), 109.82 (d, J = 5.4 Hz), 110.94 (d, J = 1.9 Hz),
125.75 (d, J = 2.3 Hz), 127.32 (d, J = 2.3 Hz), 128.45 (d, J = 6.5 Hz),
152.52 (d, J = 6.3 Hz), 140.77 (d, J = 6.3 Hz), 143.00 (d, J = 2.5 Hz),
147.20, 147.23.
Dimethyl 3-Chloro-4-nitrobenzhydrylphosphonate (1b)
Yield: 195 mg (55%); pale brown semisolid.
IR (film): 2954, 2852, 1591, 1528, 1494, 1475, 1454, 1349, 1254,
1183, 1054, 1031, 934, 907, 828, 768, 700 cm–1
.
1H NMR (500 MHz, CDCl3):  = 3.56 (d, J = 10.8 Hz, 3 H), 3.68 (d, J =
10.8 Hz, 3 H), 4.48 (d, J = 25.1 Hz, 1 H), 7.30–7.34 (m, 1 H), 7.35–7.40
(m, 2 H), 7.46–7.50 (m, 2 H), 7.60 (ddd, J = 8.8, 1.7, 1.7 Hz, 1 H), 7.68
(dd, J = 1.7, 1.7 Hz, 1H), 7.85 (d, J = 8.4 Hz, 1 H).
31P NMR (202 MHz, CDCl3):  = 22.20.
MS (EI): m/z (%) = 347 (M+ + 2, 22), 345 (M+), 238 (45), 236 (100), 220
13C NMR (125 MHz, CDCl3):  = 50.22 (d, J = 140 Hz), 53.30 (d, J = 7.0
Hz), 54.04 (d, J = 7.0 Hz), 125.84 (d, J = 1.3 Hz), 127.37, 128.12 (d, J =
2.0 Hz), 128.44 (d, J = 7.2 Hz), 129.16 (d, J = 1.0 Hz), 129.35 (d, J = 7.5
Hz), 132.60 (d, J = 8.1 Hz), 134.50 (d, J = 5.6 Hz), 143.22 (d, J = 5.0 Hz).
(13), 206 (19), 190 (41), 155 (27), 127 (24).
HRMS (EI): m/z calcd for C13H13ClNO6P: 345.0169; found: 345.0176.
© 2020. Thieme. All rights reserved. Synthesis 2020, 52, A–G

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M. Mąkosza et al.
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Synthesis
Dimethyl (4-Nitrophenyl)(thien-2-yl)methanephosphonate (3a)
Yield: 203 mg (62%); brown semisolid.
IR (KBr): 3088, 2953, 1594, 1520, 1495, 1400, 1332, 1254, 1224, 1188,
1151, 1049, 1017, 878, 835, 789, 748, 702, 526 cm–1
.
1H NMR (500 MHz, CDCl3):  = 3.56 (d, J = 10.9 Hz, 3 H), 3.70 (d, J =
10.8 Hz, 1 H), 6.93 (d, J = 25.1 Hz, 1 H), 6.96 (dd, J = 5.0, 3.6 Hz, 1 H),
7.20 (d, J = 5.0 Hz, 1 H), 7.36 (br s, 1 H), 7.67 (dd, J = 8.8, 4.1 Hz, 1 H),
8.38 (d, J = 8.2 Hz, 1 H), 8.42 (dd, J = 8.2, 2.5 Hz, 1 H), 9.03 (dd, J = 8.8,
1.6 Hz, 1 H), 9.08 (dd, J = 4.1, 1.6 Hz, 1 H).
13C NMR (125 MHz, CDCl3):  = 37.14 (d, J = 143 Hz), 53.32 (d, J = 7.5
Hz), 54.05 (d, J = 7.5 Hz), 121.35, 124.01, 124.40 (d, J = 2.5 Hz), 125.43
(d, J = 2.5 Hz), 127.04 (d, J = 2.5 Hz), 127.72 (d, J = 7.5 Hz), 128.42 (d,
J = 5.0 Hz), 132.42, 137.80 (d, J = 5.3 Hz), 143.10 (d, J = 3.8 Hz), 145.13,
145.20, 150.77.
IR (KBr): 3104, 2957, 1604, 1521, 1345, 1249, 1175, 1108, 1047, 1022,
884, 864, 801, 771, 719, 577, 555 cm–1
.
1H NMR (500 MHz, CDCl3):  = 3.61 (d, J = 10.9 Hz, 3 H), 3.67 (d, J =
10.8 Hz, 3 H), 4.81 (d, J = 25.8 Hz, 1 H), 7.01 (dd, J = 5.0, 3.7 Hz, 1 H),
7.24–7.29 (m, 2 H), 7.66–7.70 (m, 2 H), 8.20 (br d, J = 8.7 Hz, 2 H).
13C NMR (125 MHz, CDCl3):  = 45.13 (d, J = 151 Hz), 53.65 (d, J = 6.3
Hz), 54.04 (d, J = 7.5 Hz), 123.85 (d, J = 1.3 Hz), 125.80 (d, J = 2.5 Hz),
127.30 (d, J = 1.3 Hz), 127.76 (d, J = 7.5 Hz), 130.12 (d, J = 7.6 Hz),
136.47 (d, J = 6.4 Hz), 143.60 (d, J = 6.5 Hz), 147.34.
31P NMR (202 MHz, CDCl3):  = 23.83.
MS (EI): m/z (%) = 327 (M+, 22), 281 (3), 219 (23), 218 (100), 202 (11),
31P NMR (202 MHz, CDCl3):  = 25.51.
MS (EI): m/z (%) = 378 (M+, 100), 346 (22), 316 (6), 300 (11), 270 (27),
188 (7), 172 (37), 171 (40), 160 (14).
269 (90), 238 (41), 223 (64), 222 (55), 191 (19).
HRMS (EI): m/z calcd for C13H14NO5PS: 327.0330; found: 327.0325.
HRMS (EI): m/z calcd for C16H15N2O5PS: 378.0439; found: 378.0448.
Dimethyl (3-Chloro-4-nitrophenyl)(thien-2-yl)methanephospho-
nate (3b)
(Fur-2-yl)(4-nitrophenyl)acetonitrile (5a)
Yield: 187 mg (82%); pale yellow crystals; mp 82–84 °C.
Yield: 192 mg (53%); pale brown semisolid.
IR (film): 2925, 2211, 1330, 1608, 1585, 1523, 1347, 1191, 1111,
IR (film): 2955, 2852, 1591, 1526, 1475, 1351, 1254, 1183, 1053,
1014, 855, 737 595 cm–1
.
1033, 918, 829, 706 cm–1
.
1H NMR (500 MHz, CDCl3):  = 5.33 (s, 1 H), 6.38–6.41 (m, 2 H), 7.41–
7.43 (m, 2 H), 7.60 and 8.27 (AA′XX′, 4 H).
13C NMR (125 MHz, CDCl3):  = 36.47, 109.34, 111.02, 116.26, 124.44,
128.75, 139.77, 144.11, 145.90, 148.11.
MS (EI): m/z (%) = 228 (M+, 90), 211 (11), 198 (6), 182 (40), 154 (67),
1H NMR (500 MHz, CDCl3):  = 3.65 (d, J = 3.7 Hz, 3 H), 3.68 (d, J = 3.6
Hz, 3 H), 4.73 (d, J = 25.8 Hz, 1 H), 7.02 (dd, J = 5.2, 3.6 Hz, 1 H), 7.25–
7.29 (m, 2 H), 7.57 (ddd, J = 8.4, 1.8, 1.8 Hz, 1 H), 7.65 (dd, J = 1.8, 1.8
Hz, 1 H), 7.86 (d, J = 8.4 Hz, 1 H).
13C NMR (125 MHz, CDCl3):  = 45.11 (d, J = 141 Hz), 53.64 (d, J = 7.5
Hz), 54.20 (d, J = 7.5 Hz), 125.85 (d, J = 2.5 Hz), 126.02 (d, J = 2.5 Hz),
127.38 (d, J = 1.8 Hz), 127.40 (d, J = 2.5 Hz), 127.94 (J = 6.3 Hz), 128.28
(d, J = 6.3 Hz), 132.40 (d, J = 6.3 Hz), 135.80 (d, J = 6.3 Hz), 142.63 (d,
J = 5.0 Hz), 147.00.
153 (84), 140 (10), 127 (100), 116 (10), 106 (64), 77 (24).
(3-Chloro-4-nitrophenyl)(fur-2-yl)acetonitrile (5b)
Yield: 191 mg (73%); pale yellow crystals; mp 121–123 °C.
31P NMR (202 MHz, CDCl3):  = 23.30.
IR (film): 2210, 1733, 1609, 1584, 1530, 1347, 1199, 1146, 1095,
1051, 1015, 837, 747 cm–1
.
MS (EI): m/z (%) = 363 (M+ + 2, 14), 361 (M+, 32), 254 (46), 253 (25),
252 (100), 236 (8), 222 (12), 208 (19), 206 (38), 171 (40), 159 (11),
127 (9), 109 (19).
1H NMR (500 MHz, CDCl3):  = 5.27 (s, 1 H), 6.41 (dd, J = 3.2, 1.6 Hz, 1
H), 6.43 (br d, J = 3.2 Hz, 1 H), 7.44 (d, J = 1.6 Hz, 1 H), 7.44 (d, J = 1.6
Hz, 1 H), 7.47 (dd, J = 8.3, 1.9 Hz, 1 H), 7.61 (d, J = 1.9 Hz, 1 H), 7.92 (d,
J = 8.3 Hz, 1 H).
HRMS (EI): m/z calcd for C13H13ClNO5SP 360.9941; found: 360.9935.
Dimethyl (2-Chloro-4-nitrophenyl)(thien-2-yl)methanephospho-
nate (3c)
13C NMR (125 MHz, CDCl3):  = 36.06, 109.61, 111.10, 115.80, 126.39,
126.85, 128.18, 131.10, 138.70, 144.32, 145.31.
MS (EI): m/z (%) = 264 (M+ + 2, 43), 262 (100), 245 (9), 227 (32), 217
(19), 216 (30), 215 (20), 204 (10), 189 (22), 188 (28), 187 (36), 181
(15), 169 (15), 153 (57), 152 (39), 141 (15), 140 (29), 127 (18), 126
(31), 125 (21), 114 (17), 106 (68), 99 (16).
Yield: 142 mg (39%); pale brown semisolid.
IR (KBr): 3088, 2953, 1594, 1520, 1495, 1400, 1332, 1254, 1224, 1188,
1049, 1017, 878, 835, 789, 748, 702, 526 cm–1
.
1H NMR (500 MHz, CDCl3):  = 3.64 (d, J = 10.8 Hz, 3 H), 3.70 (d, J =
10.8 Hz, 3 H), 5.45 (d, J = 25.5 Hz, 1 H), 6.99 ( dd, J = 5.1, 3.7 Hz, 1 H),
6.99 (dd, J = 5.2, 3.5 Hz, 1 H), 7.24–7.29 (m, 2 H), 8.13 (dd, J = 8.6, 2.1
Hz, 1 H), 8.17 (dd, J = 8.6, 2.1 Hz, 1 H), 8.29 (br s, 1 H).
13C NMR (125 MHz, CDCl3):  = 41.00 (d, J = 142 Hz), 53.54 (d, J = 7.2
Hz), 54.31 (d, J = 7.6 Hz), 122.08 (d, J = 2.2 Hz), 124.80, 126.06 (d, J =
2.2 Hz), 127.23 (d, J = 2.7 Hz), 128.02 (d, J = 7.8 Hz), 131.56 (d, J = 4.4
Hz), 134.72 (d, J = 10.5 Hz), 135.75 (d, J = 6.1 Hz), 141.53 (d, J = 2.5 Hz),
147.33.
HRMS (EI): m/z calcd for C12H7ClN2O3: 262.0145; found: 262.0148.
(2-Chloro-4-nitrophenyl)(fur-2-yl)acetonitrile (5c)
Yield: 130 mg (50%); pale brown oil.
IR (film): 3103, 2927, 2251, 1590, 1528, 1473, 1351, 1184, 11443,
1119, 1014, 892, 818, 742 cm–1
.
1H NMR (500 MHz, CDCl3):  = 5.73 (s, 1 H), 6.39–6.43 (m, 2 H), 7.42
(br s, 1 H), 7.76 (d, J = 8.6 Hz, 1 H), 8.20 (dd, J = 8.6, 2.3 Hz, 1 H), 8.33
(d, J = 2.3 Hz, 1 H).
13C NMR (125 MHz, CDCl3):  = 34.04, 109.94, 111.05, 115.71, 122.59,
125.31, 130.50, 134.35, 137.67, 144.19, 144.40, 148.47.
31P NMR (202 MHz, CDCl3):  = 23.30.
MS (EI): m/z (%) = 363 (32), 361 (M+, 29), 254 (47), 252 (100), 237 (9),
208 (17), 206 (37), 171 (37), 159 (10).
HRMS (ESI): m/z (M+ – 1) calcd for C12H6ClN2O3: 261.0067; found:
HRMS (EI): m/z calcd for C13H13ClNO5PS: 360.9941; found: 360.9954.
261.0073
(5-Nitroquinol-8-yl)(thien-2-yl)methanephosphonate (3e)
Yield: 158 mg (42%); pale brown solid; mp 119–121 °C.
© 2020. Thieme. All rights reserved. Synthesis 2020, 52, A–G

F
M. Mąkosza et al.
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Synthesis
(Fur-2-yl)(4-nitronaphth-1-yl)acetonitrile (5d)
(4-Nitronaphth-1-yl)(thien-2-yl)acetonitrile (6d)
Yield: 222 mg (80%); yellowish crystals; mp 137–139 °C.
Yield: 88 mg (30%); pale brown semisolid.
IR (film): 3125, 3063, 2924, 2825, 2251, 1604, 1528, 1367, 1346,
IR (film): 3087, 2195, 1659, 1523, 1413, 1354, 1262, 1098, 808, 765,
735 cm–1
1259, 1227, 1146, 1069, 1014, 866, 824, 795, 766, 745 cm–1
.
.
1H NMR (500 MHz, CDCl3):  = 5.96 (s, 1 H), 6.32 (d, J = 3.2 Hz, 1 H),
6.38 (br s, 1 H), 7.42 (br s, 1 H), 7.70–7.78 (m, 3 H), 8.07 (d, J = 8.5 Hz,
1 H), 8.16 (d, J = 7.9 Hz, 1 H), 8.53 (d, J = 8.6 Hz, 1 H).
13C NMR (125 MHz, CDCl3):  = 34.47, 109.81, 111.10, 116.61, 122.77,
123.15, 124.09, 125.19, 125.49, 128.61, 129.47, 131.10, 134.70,
143.82, 145.89, 147.88.
MS (EI): m/z (%) = 278 (M+, 100), 261 (10), 249 (11), 231 (33), 221
(15), 205 (38), 204 (36), 203 (54), 177 (37), 176 (38), 165 (30), 151
(19).
1H NMR (500 MHz, CDCl3):  = 6.11 (s, 1 H), 7.00 (dd, J = 4.8, 3.6 Hz, 1
H), 7.10 (m, 1 H), 7.31 (d, J = 4.7 Hz, 1 H), 7.69 (m, 1 H), 7.76 (m, 1 H),
7.84 (d, J = 7.8 Hz, 1 H), 8.07 (d, J = 8.4 Hz, 1 H), 8.18 (d, J = 7.8 Hz, 1 H),
8.53 (d, J = 8.4 Hz, 1 H).
13C NMR (125 MHz, CDCl3):  = 35.64, 117.94, 122.82, 123.34, 124.15,
125.07, 125.58, 127.02, 127.38, 127.63, 128.66, 129.52, 130.92,
136.36, 136.73, 147.88.
MS (EI): m/z (%) = 294 (M+, 100), 277 (14), 249 (23), 248 (28), 247
(55), 246 (52), 237 (11), 222 (17), 221 (36), 220 (13), 190 (9), 176 (11),
164 (21), 126 (25), 122 (52).
HRMS (EI): m/z calcd for C16H10N2O3: 278.0691; found: 278.0696.
HRMS (EI): m/z calcd for C16H10N2O2S: 294.0463; found: 194.0463.
(4-Nitrophenyl)(thien-2-yl)acetonitrile (6a)
(3-Iodo-4-nitrophenyl)(thien-2-yl)acetonitrile (6f)
Yield: 188 mg (77%); pale yellow crystals; mp 62–63 °C.
Yield: 160 mg (46%); pale brown solid; mp 95–97 °C.
IR (KBr): 3090, 2247, 1581, 1526, 1348, 1035, 851, 822, 708 cm–1
.
R (film): 3111, 3080, 2922, 2248, 1608, 1998, 1521, 1347, 1111, 1015,
852, 818, 702 cm–1
.
1H NMR (500 MHz, CDCl3):  = 5.49 (s, 1 H), 7.02 (dd, J = 5.1, 3.7 Hz, 1
H), 7.12 (d, J = 3.7 Hz, 1 H), 7.34 (d, J = 5.1 Hz, 1H), 7.61 and 8.27
(AA′XX′, 4 H).
1H NMR (500 MHz, CDCl3):  = 5.39 (s, 1 H), 7.03 (dd, J = 4.9, 3.3 Hz, 1
H), 7.12 (d, J = 3.3 Hz, 1 H), 7.36 (d, J = 4.9 Hz, 1 H), 7.55 (dd, J = 8.4, 1.5
Hz, 1 H), 7.88 (d, J = 8.4 Hz, 1 H), 8.07 (d, J = 1.7 Hz, 1 H).
13C NMR (125 MHz, CDCl3):  = 37.63, 117.64, 124.53, 127.27, 127.44,
13C NMR (125 MHz, CDCl3):  = 36.86, 87.18, 117.21, 126.08, 127.47,
127.45, 128.58, 136.39, 142.10, 148.04.
127.54, 127.62, 128.19, 135.84, 140.79, 140.88, 152.99.
MS (EI): m/z (%) = 244 (M+, 100), 227 (14), 216 (7), 198 (36), 197 (30),
MS (EI): m/z (%) = 370 (M+, 99), 324 (6), 269 (9), 260 (11), 244 (100),
196 (22), 171 (35), 154 (17), 127 (13), 122 (45).
227 (14), 198 (51), 197 (64), 196 (60), 171 (50), 154 (18), 122 (82).
HRMS (EI): m/z calcd for C12H8N2O2S: 244.0306; found: 244.0313.
HRMS (EI): m/z calcd for C12H7IN2O2S: 369.9273; found: 369.9279.
(3-Chloro-4-nitrophenyl)(thien-2-yl)acetonitrile (6b)
Yield: 138 mg (85%); pale yellow solid; mp 36–38 °C.
Supporting Information
IR (film): 2922, 2247, 1586, 1529, 1475, 1350, 1238, 1052, 884, 829,
Supporting information for this article is available online at
709 cm–1
.
https://doi.org/10.1055/s-0040-1707230.
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1H NMR (500 MHz, CDCl3):  = 5.43 (s, 1 H), 7.03 (dd, J = 5.1, 3.5 Hz, 1
H), 7.13 (d, J = 3.5 Hz, 1 H), 7.37 (d, J = 5.1 Hz, 1 H), 7.48 (dd, J = 8.4, 2.0
Hz, 1 H), 7.61 (d, J = 2.0 Hz, 1 H), 7.93 (d, J = 8.4 Hz, 1 H).
References
13C NMR (125 MHz, CDCl3):  = 37.22, 117.18, 126.51, 126.67, 127.54,
(1) (a) Goliński, J.; Mąkosza, M. Tetrahedron Lett. 1978, 3495.
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(c) Mąkosza, M.; Wojciechowski, K. Chem. Rev. 2004, 104, 2631.
(d) Mąkosza, M. Chem. Soc. Rev. 2010, 39, 2855. (e) Mąkosza, M.
Synthesis 2017, 49, 3247. (f) Loska R., Mąkosza M.; Synthesis
2020, 52: in press; DOI: 10.1055/s-0040-1707149.
(2) Mąkosza, M.; Goliński, J. Angew. Chem. Int. Ed. 1982, 21, 451.
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127.57, 126.69, 128.27, 130.92, 135.65, 141.01, 147.77.
MS (EI): m/z (%) = 280 (M+ + 2, 27), 278 (76, M+), 261 (5), 243 (23), 231
(11), 213 (10), 197 (40), 196 (48), 184 (7), 170 (10), 148 (9), 122 (100),
95 (11), 75 (18).
HRMS (ESI): m/z (M+ – 1) calcd for C12H6ClN2O2S: 276.9839; found:
276.9830.
(2-Chloro-4-nitrophenyl)(thien-2-yl)acetonitrile (6c)
Yield: 235 mg (50%); pale brown semisolid.
(4) (a) Mąkosza, M.; Winiarski, J. Chem. Lett. 1984, 13, 1623.
(b) Mąkosza, M.; Danikiewicz, W.; Wojciechowski, K. Liebigs
Ann. Chem. 1988, 203.
IR (KBr): 3102, 2249, 1523, 1471, 1351, 1118, 1046, 894, 853, 812,
738, 711 cm–1
.
1H NMR (500 MHz, CDCl3):  = 5.89 (s, 1 H), 7.02 (dd, J = 5.1, 3.6 Hz, 1
H), 7.15 (d, J = 3.6 Hz, 1 H), 7.34 (dd, J = 5.2, 1.1 Hz, 1 H), 7.81 (dd, J =
8.6, 2.3 Hz, 1 H), 8.33 (d, J = 2.3 Hz, 1 H).
(5) Mąkosza, M.; Winiarski, J. J. Org. Chem. 1984, 49, 1494.
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1446.
13C NMR (125 MHz, CDCl3):  = 35.14, 117.16, 122.77, 125.42, 127.26,
127.39, 127.75, 130.23, 134.06, 134.79, 140.00, 148.41.
MS (EI): m/z (%) = 280 (M+ + 2, 47 ), 278 (100, M+), 251 (14), 243 (33),
232 (18), 216 (14), 205 (27), 197 (31), 196 (39), 170 (13), 122 (56).
HRMS (EI): m/z calcd for C12H7ClN2O2S: 277.9917; found: 277.9920.
© 2020. Thieme. All rights reserved. Synthesis 2020, 52, A–G

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M. Mąkosza et al.
Paper
Synthesis
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© 2020. Thieme. All rights reserved. Synthesis 2020, 52, A–G