New Cyano-Group-Containing 1,3-Oxaselenoles: Nucleophilic Substitution of a Cyano Group with Rearrangement

Article abstract of DOI:10.1055/s-0037-1609939

New cyano-group-containing 1,3-oxaselenoles were obtained by the treatment of aroylacetonitriles with selenium(IV) oxide. The resulting products were shown to react with ammonia, hydrazine, or primary amines; this reaction was accompanied by aryl rearrangement.

Full text of DOI:10.1055/s-0037-1609939

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Georg Thieme Verlag Stuttgart · New York
2018, 29, A–D
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Synlett
A. V. Kachanov et al.
Letter
New Cyano-Group-Containing 1,3-Oxaselenoles: Nucleophilic
Substitution of a Cyano Group with Rearrangement
Andrey V. Kachanov*a
O
O
Andrey V. Zamaraevb
Andrey V. Gerasimenkoc
Konstantin V. Maslova
Oleg Yu. Slabkoa
CN
Se
R
Ar
O
N
H
Ar
SeO2, Δ
– 2H2O
R
NH2
2
Ar
O
O
Se
CN
– HCN
Ar = Ph, 4-MeOC6H4
Ar
CN
77–81%
2 examples
Ar
CN
37–61%
0 examples
1
Vladimir A. Kaminskiia
R = H, NH2, CH2Ph, 4-Tol, 4-MeOC6H4
a
Far Eastern Federal University, School of Natural Sciences,
Sukhanov Str., 8, Vladivostok 690950, Russian Federation
kachanov.av@dvfu.ru
G. B. Elyakov Pacific Institute of Bioorganic Chemistry, Far East
b
Branch of the Russian Academy of Sciences, prospect 100 let
Vladivostoku, 159, Vladivostok 690022, Russian Federation
Institute of Chemistry, Far East Branch of the Russian Academy
c
of Sciences, prospect 100 let Vladivostoku, 159, Vladivostok
690022, Russian Federation
Received: 04.06.2018
Accepted after revision: 06.08.2018
Published online: 24.08.2018
In this study, we used aroylacetonitriles as active meth-
ylene group-containing malononitrile analogues. We found
that, on treatment with selenium(IV) oxide, aroylacetoni-
triles 1 and 2 underwent heterocyclization to give the pre-
viously unknown cyano-group-containing 1,3-oxaselenoles
DOI: 10.1055/s-0037-1609939; Art ID: st-2018-v0337-l
Abstract New cyano-group-containing 1,3-oxaselenoles were ob-
tained by the treatment of aroylacetonitriles with selenium(IV) oxide.
The resulting products were shown to react with ammonia, hydrazine,
or primary amines; this reaction was accompanied by aryl rearrange-
ment.
3
and 4 (Scheme 1) in good yields. The starting aroylaceto-
nitriles were obtained from the methyl esters of the corre-
sponding aromatic acids.7
Key words aroylacetonitriles, selenium oxide, oxaselenoles, nucleo-
O
philic substitution, rearrangement
CN
Se
O
Ar
CN
SeO2, Δ
O
2
Ar
toluene
1
,3-Oxaselenoles are an underinvestigated group of het-
Ar
CN
1, 2
3, 4
erocyclic compounds. They are most often prepared by the
interaction of selenium(IV) oxide with cyclic 1,3- or 1,2-di-
carbonyl compounds or, in some cases, with 1,3,5-tricar-
bonyl compounds. 1,3-Oxaselenoles are also obtained by
the addition of the SeCN anion to certain epoxides, and
3
Ar = Ph, 4 Ar = 4-MeOC6H4
Scheme 1 Formation of 1,3-oxaselenoles 3 and 4 from aroylacetonitriles
1
–
2
The formation of oxaselenoles 3 and 4 from the aroy-
lacetonitriles 1 and 2 occurred optimally on reaction for
five hours in boiling toluene. Other solvents, for example,
they can also be synthesized via α-carbonyl-stabilized sul-
fur ylides or by using α-bromoacetophenones. 1,3-Oxas-
3
4
8
elenoles can also be prepared from 2-oxo-1,2-diphenylethyl
1,4-dioxane, can also be used as reaction media. However,
when 1,4-dioxane was used, the resulting product con-
tained small amounts of insoluble impurities. The proposed
mechanism for the formation of oxaselenoles 3 and 4 is
similar to that previously proposed for the formation of ox-
5
selenocyanate.
1
,3-Selenocyanates are known to react with bromine.1a
They can react with diazomethane to form 1,4,7-dioxasele-
1
e,f
nocines.
A method for converting 1,3-oxaselenole into
4
1d
oxaselenolium perchlorates is also known. However, the
reactions of 1,3-oxaselenoles with N-nucleophiles has not
previously been reported.
aselenoles from cyclic 1,3-dicarbonyl compounds.
The crystalline form of the product 4 was subjected to
X-ray analysis, which confirmed its structure to be that of
2-(4-methoxybenzoyl)-5-(4-methoxyphenyl)-1,3-oxasele-
nole-2,4-dicarbonitrile (Figure 1).9
We previously studied the interaction of malononitrile
with selenium(IV) oxide. Depending on the reaction condi-
tions, this proceeds with the formation of various products:
pyridinium ylides, tetracyanoethylene, 1,1,2,3,3-penta-
During chromatography of 1,3-oxaselenoles 3 and 4 on
Al O (eluent: 1,2-dichloroethane), elimination of the aroyl
2
3
5
6
cyanopropene salts, or triselenodicyanide.
fragment occurred to form the corresponding 2,4-dicyano-
-aryl-1,3-oxazenolenes 5 and 6, respectively. The weakly
5
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A. V. Kachanov et al.
Letter
to give the substituted amides 7a–e and 8a–e. In this reac-
tion, the cyano group at the 2-position is replaced by an
aryl fragment that migrates from the carbonyl function. A
suggested mechanism of interaction is shown in Scheme 3.
The amides 7a–e and 8a–e were prepared from the oxasele-
noles 3 and 4 by cooling the reactants in an ethanol or ace-
tonitrile medium.11 The resulting products were amor-
phous or fine crystalline substances with a gray or pale-yel-
low color that precipitated spontaneously from of the
reaction mixture as the reaction proceeded. The yield of the
products purified by crystallization reached 61%.
Figure 1 X-Ray structure of compound 4
R
O
O
NH2
Ar
CN
Se
R
Ar
N
H
O
O
Se
basic nature of the sorbent contributes to this reaction.
Elimination of the aroyl fragment did not occur during
chromatography on silica gel. The proposed mechanism for
the dearoylation reaction is shown in Scheme 2.1
1
) –CN
Ar
CN
2) – H
Ar
CN
7, 8a–e
3
, 4
7
Ar = Ph, 8 Ar = 4-MeOC6H4
0
a R = H, b R = NH2, c R = CH2Ph, d R = 4-Tol, e R=p-MeOPh
Scheme 3 Nucleophilic substitution of cyano group with rearrange-
ment in reactions of oxaselenoles 3 and 4 with amines.
O
HO
CN
Se
CN
Se
H
O
CN
Se
Ar
H2O
– O
O
O
O
–
The product structures were confirmed by IR and 1
H
Ar
CN
Ar
OH Ar
, 5 Ar = Ph
, 6 Ar = 4-MeOC6H4
CN
Ar
CN
3, 4
5, 6
and 13С NMR spectra. The IR spectra for all compounds 7a–e
and 8a–e were characterized by the presence of an absorp-
tion band for the amide group. The proton signals of the
3
4
Scheme 2 Dearoylation mechanism of oxaselenoles 3 and 4
NH group for products 7a and 8a were observed as two
2
separate and equally intense signals. For compounds 7c and
8c, the proton signals of the N–H group underwent splitting
and appeared as triplet signals. In this case, the signals of
the protons of the benzyl group also underwent splitting,
In the IR spectra of products 5 and 6, a broadened ab-
sorption band for the CN groups at 2195–2206 cm–1 re-
mained unchanged. There was also an absence of an ab-
sorption band in the carbonyl group region compared with
the spectra of the starting substances. This showed the ab-
indicating the absence of rotation around the N–CH bond.
2
A comparison of the X-ray data for oxaselenole 4 (Figure
1
9
sence of the benzoyl-fragment. The Н NMR spectra of
1) and substitution product 7с (Figure 2) showed the dif-
products 5 and 6 contained proton signals for only one aro-
matic nucleus, and an additional signal with an intensity
corresponding to 1 H appeared at δ = 7.2 ppm. The GC/MS
ferent positions of the aryl substituent originally at position
spectra showed isotope splittings for the molecular ions
+
[
M ], and the m/z values coincided with the calculated ones.
Oxaselenoles 3 and 4 and their products are unstable
compounds with respect to oxygen, and during prolonged
storage they are oxidized with the release of elementary se-
lenium. One product of atmospheric oxidation of oxasele-
nole 3 is benzoic acid; this was isolated by sublimation
from a partially oxidized sample.
Oxidation of oxaselenole 3 with hydrogen peroxide also
led to the formation of benzoic acid. The extraction mixture
of oxidation products was analyzed by GC/MS. The starting
aroylacetonitrile 1 was found in the mixture as a second
component, and its presence was confirmed by the detec-
tion of an absorption band for the unconjugated cyano
group in the IR spectrum of the isolated mixture.
A peculiarity of the 2-cyano-containing oxaselenoles 3
and 4 is their ability to interact selectively with such active
N-nucleophiles as ammonia, primary amines, or hydrazine
Figure 2 X-Ray structure of compound 7c
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Georg Thieme Verlag Stuttgart · New York — Synlett 2018, 29, A–D

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A. V. Kachanov et al.
Letter
2
, before and after the reaction. Therefore, the rearrange-
H). 13C NMR (100 MHz, DMSO-d ): δ = 45.2, 79.6, 114.4, 116.0,
6
1
26.6, 127.9, 129.2, 129.3, 129.7, 130.2, 132.5, 135.0, 160.8,
ment process under the conditions of the reaction was con-
firmed.
+
183.8. LC/MS (APCI): m/z [M ] calcd for C18H N O Se: 365.99;
10
2
2
found: 365.98.
In conclusion, it should be noted that the number of
known oxaselenoles is small. We have found a method for
synthesizing new 2-cyano-1,3-oxaselenoles. These com-
pounds eliminate a cyano group and undergo rearrange-
ment on treatment with an active N-nucleophile. The oxa-
selenoles were obtained from unsubstituted or electron-do-
nating-group-containing aroylacetonitriles. Unfortunately,
attempts to obtain aroylacetonitriles with an electron-ac-
ceptor nitro group were unsuccessful.
2
-(4-Methoxybenzoyl)-5-(4-methoxyphenyl)-1,3-oxasele-
nole-2,4-dicarbonitrile (4)
Orange solid; yield: 5.57 g (77%); mp 122–124 °C. IR (KBr):
–1 1
3076, 2843, 2205, 1655, 1593 cm . H NMR (400 MHz, DMSO-
): δ = 3.85 (s, 3 H), 3.88 (s, 3 H), 7.14 (d, J = 9.0 Hz, 4 H), 7.87
d
6
13
(d, J = 9.0 Hz, 2 H), 8.12 (d, J = 9.0 Hz, 2 H). C NMR (100 MHz,
DMSO-d ): δ = 55.7, 55.9, 76.5, 79.20, 114.6, 114.7, 114.9, 116.2,
6
118.8, 122.5, 130.0, 132.4, 160.8, 162.3, 164.6, 182.4.
(
9) CCDC 1824131 and 1824130 contain the supplementary crys-
tallographic data for compounds 4 and 7c, respectively. The data
can be obtained free of charge from The Cambridge Crystallo-
graphic Data Centre via www.ccdc.cam.ac.uk/getstructures.
10) 1,3-Oxaselenole-2,4-dicarbonitriles 5 and 6; General Method
The appropriate oxaselenole 3 or 4 (300.0 mg) was applied to a
chromatographic plate measuring 250 × 300 mm with an unat-
tached layer of Al O , and was eluted four times with DCE.
Supporting Information
(
Supporting information for this article is available online at
https://doi.org/10.1055/s-0037-1609939.
S
u
p
p
ortioIgnfrm oaitn
S
u
p
p
ortioIgnfrm oaitn
2
3
During the chromatography, dearoylation occurred and the
color of the upper spot changed from yellow to pale yellow. Part
of the upper area was collected and extracted with DCE. The
solvent was evaporated and the semi-solid residue was dis-
References and Notes
(
1) (a) Stamm, H.; Gossrau, K. Ber. Dtsch. Chem. Ges. A 1933, 66,
solved in an Et O–hexane mixture. The resulting solution was
1558. (b) Borsche, W.; Hartmann, H. Ber. Dtsch. Chem. Ges. A
2
slowly evaporated at r.t. over a few days. The resulting crystals
were separated and dried under reduced pressure.
1940, 73, 839. (c) Laitalainen, T.; Simonen, T.; Kivekäs, R. Tetra-
hedron Lett. 1978, 19, 3079. (d) Laitalainen, T.; Simonen, T.;
Kivekäs, R.; Klinga, M. J. Chem. Soc., Perkin Trans. 1 1983, 333.
5
-Phenyl-1,3-oxaselenole-2,4-dicarbonitrile (5)
Gray solid; yield: 50.0 mg (24%); mp 78–79 °C. IR (KBr): 2997,
(
e) Matoba, K.; Yamazaki, T. Chem. Pharm. Bull. 1987, 35, 4967.
f) Matoba, K.; Yamazaki, T. Heterocycles 1983, 20, 1959.
2) (a) Robert, A.; Le Maréchal, A. M. J. Chem. Soc., Chem. Commun.
978, 447. (b) Le Maréchal, A. M.; Robert, A.; Leban, I. J. Chem.
–
1 1
2
206, 1595 cm . H NMR (400 MHz, DMSO-d ): δ = 7.24 (s, 1
(
6
13
H), 7.58 (m, 3 H), 7.78 (m, 2 H). C NMR (100 MHz, DMSO-d ):
(
6
δ = 65.4, 77.7, 114.9, 117.5, 127.0, 127.3, 129.4, 132.2, 161.3.
1
+
GC/MS: m/z [M ] calcd for C H N OSe: 261.97, found: 262.00.
Soc., Perkin Trans. 1 1993, 351.
11
6
2
5
-(4-Methoxyphenyl)-1,3-oxaselenole-2,4-dicarbonitrile (6)
(3) Nakayama, J.; Sugiura, H.; Hoshino, M.; Kobayashi, H. Tetrahe-
dron Lett. 1985, 26, 2201.
Gray solid; yield: 70.0 mg (33%); mp 100–101 °C. IR (KBr): 2934,
–1 1
2
839, 2195, 1607 cm . H NMR (400 MHz, DMSO-d ): δ = 3.83
(
(
4) Weber, M.; Hartmann, H. Z. Chem. 1987, 27, 95.
5) Gramza, M.; Mitchell, R. B.; Dittmer, D. C. J. Org. Chem. 1984, 49,
6
(
s, 3 H), 7.11 (d, J = 9.0 Hz, 2 H), 7.20 (s, 1 H), 7.76 (d, J = 9.0 Hz, 2
13
H). C NMR (100 MHz, DMSO-d ): δ = 55.7, 65.0, 74.6, 114.8,
1
2057.
6
+
15.4, 117.6, 119.3, 129.3, 161.3, 162.1. GC/MS: m/z [M ] calcd
(
6) (a) Kachanov, A. V.; Slabko, O. Yu.; Skronts, M. V.; Kaminskii, V.
A. Russ. J. Org. Chem. 2006, 42, 774. (b) Kachanov, A. V.; Slabko,
O. Yu.; Kaminskii, V. A. Russ. J. Org. Chem. 2017, 53, 462.
for C12H N O Se: 291.98, found: 292.00.
8
2
2
(
11) Replacement Products 7a–e and 8a–e; General Procedure
A solution of the appropriate oxaselenole 3 or 4 (1.6 mmol) in
(c) Kaminskii, V. A.; Slabko, O. Yu.; Kachanov, A. V.; Buhvetskii,
EtOH or MeCN (3 mL) was cooled and aq NH , N H ·H O, or a
B. V. Tetrahedron Lett. 2003, 44, 139. (d) Kachanov, A. V.; Slabko,
O. Yu.; Baranova, O. V.; Shilova, E. V.; Kaminskii, V. A. Tetrahe-
dron Lett. 2004, 45, 4461.
3
2
4
2
primary amine was added with stirring. After 2 h, the product
spontaneously precipitated as an amorphous precipitate that
was collected by filtration, washed once with the cooled sol-
vent, and dried. The resulting product was crystallized from the
appropriate solvent.
(7) Baba, A.; Yasuma, T.; Tawada, H.; Yamashita, M. WO
2005111046, 2005.
(8) 2-Aroyl-1,3-oxaselenole-2,4-dicarbonitriles 3 and 4: General
Procedure
4
-Cyano-2,5-diphenyl-1,3-oxaselenole-2-carboxamide (7a)
White solid; yield: 227.3 mg (40%); mp 207–208 °C (THF–hex-
The appropriate aroylacetonitrile 1 or 2 (34 mmol) and SeO2
ane). IR (KBr): 3393, 3312, 3061, 2210, 1674, 1593 cm–1
.
1
H
(5.66 g, 51 mmol) were added successively, with stirring, to
NMR (400 MHz, DMSO-d ): δ = 7.41–7.47 (m, 3 H), 7.56–7.62
toluene (100 mL), and the mixture was heated to boiling for 5 h
until the reaction was complete (TLC). During the reaction, the
color of the mixture changed from yellow to dark-red, and a
small amount of gray selenium precipitated. The solution was
then decanted and the solvent was evaporated to give an oily
residue that was dried under reduced pressure. If necessary, the
product could be purified chromatographically (silica gel, DCE).
6
(m, 3 H), 7.64 (d, J = 7.7 Hz, 1 H), 7.65 (d, J = 8.2 Hz, 1 H), 7.99 (s,
1
H), 8.13 (d, J = 8.0 Hz, 1 H), 8.14 (d, J = 7.3 Hz, 1 H), 8.21 (s, 1
13
H). C NMR (100 MHz, DMSO-d ): δ = 75.2, 97.7, 115.1, 125.1,
6
127.4, 127.5, 128.6, 129.2, 129.6, 131.9, 139.6, 160.4, 170.1.
4
-Cyano-2,5-diphenyl-1,3-oxaselenole-2-carbohydrazide
(7b)
White solid; yield: 335.1 mg (57%); mp 184–185 °C (toluene). IR
2-Benzoyl-5-phenyl-1,3-oxaselenole-2,4-dicarbonitrile (3)
–
1 1
(KBr): 3325, 3275, 3063, 2199, 1663, 1597 cm
. H NMR (400
Red oil; yield: 5.03 g (81%). IR (KBr): 3067, 2206, 1701, 1597
–1 1
MHz, DMSO-d ): δ = 4.58 (s, 2 H), 7.40–7.46 (m, 3 H), 7.57–7.61
cm . H NMR (400 MHz, DMSO-d ): δ = 7.57–7.66 (m, 5 H), 7.76
6
6
(
m, 3 H), 7.63 (d, J = 7.8 Hz, 1 H), 7.64 (d, J = 8.3 Hz, 1 H), 8.17 (d,
(t, J = 7.4 Hz, 1 H), 7.90 (d, J = 8.5 Hz, 2 H), 8.13 (d, J = 8.5 Hz, 2
13
J = 8.0 Hz, 1 H), 8.18 (d, J = 7.3 Hz, 1 H), 10.06 (s, 1 H). C NMR
©
Georg Thieme Verlag Stuttgart · New York — Synlett 2018, 29, A–D

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Synlett
A. V. Kachanov et al.
Letter
(
1
100 MHz, DMSO-d ): δ = 75.2, 97.4, 115.1, 125.0, 127.4, 127.5,
28.6, 129.2, 129.7, 131.9, 139.8, 160.4, 166.9.
4-Cyano-2,5-bis(4-methoxyphenyl)-1,3-oxaselenole-2-car-
bohydrazide (8b)
6
N-Benzyl-4-cyano-2,5-diphenyl-1,3-oxaselenole-2-carbox-
amide (7c)
Pale-yellow solid; yield: 344.2 mg (50%); 106–108 °C (toluene).
IR (KBr): 3352, 3323, 2935, 2839, 2201, 1670, 1607 cm–1
.
1
H
White solid; yield: 299.0 mg (42%); mp 169–170 °C (toluene). IR
NMR (400 MHz, DMSO-d ): δ = 3.74 (s, 3 H), 3.85 (s, 3 H), 4.55
6
–1 1
(KBr): 3312, 3065, 2851, 2205, 1659, 1593 cm
.
H NMR (400
(s, 2 H); 6.97 (d, J = 8.9 Hz, 2 H), 7.12 (d, J = 8.9 Hz, 2 H), 7.54 (d,
MHz, DMSO-d ): δ = 4.36 (m, 2 H), 7.15–7.29 (m, 5 H), 7.41–
J = 8.9 Hz, 2 H), 8.13 (d, J = 8.9 Hz, 2 H), 10.00 (s, 1 H). 13C NMR
6
7.48 (m, 3 H), 7.57–7.63 (m, 3 H), 7.66 (d, J = 7.4 Hz, 1 H), 7.67
(100 MHz, DMSO-d ): δ = 55.4, 55.7, 72.2, 97.4, 113.9, 114.6,
6
(
d, J = 8.0 Hz, 1 H), 8.12 (d, J = 7.9 Hz, 1 H), 8.13 (d, J = 7.1 Hz, 1
115.7, 120.0, 126.6, 129.5, 131.5, 160.2, 160.6, 161.9, 167.1.
N-Benzyl-4-cyano-2,5-bis(4-methoxyphenyl)-1,3-oxasele-
nole-2-carboxamide (8c)
13
H), 9.31 (t, J = 6.1 Hz, 1 H). C NMR (100 MHz, DMSO-d ):
δ = 42.5, 75.4, 97.4, 115.0, 125.1, 127.0, 127.1, 127.4, 128.4,
6
1
4
28.7, 129.2, 129.7, 131.9, 138.7, 139.5, 160.5, 168.2.
-Cyano-N-(4-tolyl)-2,5-diphenyl-1,3-oxaselenole-2-carbox-
Pale-yellow solid; yield: 336.6 mg (42%); 133–134 °C (toluene).
IR (KBr): 3319, 2930, 2837, 2197, 1653, 1607 cm . H NMR
–1
1
amide (7d)
(400 MHz, DMSO-d ): δ = 3.75 (s, 3 H), 3.84 (s, 3 H), 4.35 (qd,
6
White solid; yield: 315.7 mg (44%); 145–146 °C (EtOH). IR
J = 15.3, 6.2 Hz, 2 H), 6.99 (d, J = 9.0 Hz, 2 H), 7.13 (d, J = 9.0 Hz, 2
H), 7.17–7.30 (m, 5 H), 7.57 (d, J = 8.8 Hz, 2 H), 8.08 (d, J = 9.0
–1 1
(KBr): 3331, 3055, 2920, 2201, 1663, 1595 cm
. H NMR (400
13
MHz, DMSO-d ): δ = 2.25 (s, 3 H), 7.15 (d, J = 8.3 Hz, 2 H), 7.45–
Hz, 2 H), 9.25 (t, J = 6.2 Hz, 1 H). C NMR (100 MHz, DMSO-d ):
6
6
7
.51 (m, 5 H), 7.60–7.64 (m, 3 H), 7.73 (d, J = 8.0 Hz, 1 H), 7.74
δ = 42.5, 55.4, 55.7, 72.4, 97.4, 114.0, 114.6, 115.7, 120.0, 126.8,
127.0, 128.4, 129.5, 131.2, 138.8, 160.2, 160.6, 161.9, 168.4.
4-Cyano-2,5-bis(4-methoxyphenyl)-N-(4-tolyl)-1,3-oxasele-
nole-2-carboxamide (8d)
13
(d, J = 8.4 Hz, 1 H), 8.13–8.16 (m, 2 H), 10.31 (s, 1 H). C NMR
(100 MHz, DMSO-d ): δ = 20.5, 75.6, 97.8, 115.1, 121.2, 125.7,
6
1
1
4
27.5, 127.6, 128.8, 129.2, 129.9, 131.9, 134.1, 134.8, 138.9,
60.6, 166.7.
White solid; yield: 490.6 mg (61%); 158–161 °C (EtOH). IR
–1 1
-Cyano-N-(4-methoxyphenyl)-2,5-diphenyl-1,3-oxasele-
(KBr): 3330, 3055, 2201, 1663, 1595 cm . H NMR (400 MHz,
nole-2-carboxamide (7e)
DMSO-d ): δ = 2.25 (s, 3 H), 3.75 (s, 3 H), 3.85 (s, 3 H), 7.02 (d,
6
White solid; yield: 274.0 mg (37%); 123–124 °C (EtOH). IR
J = 8.9 Hz, 2 H), 7.15 (d, J = 8.9 Hz, 4 H), 7.46 (d, J = 8.5 Hz, 2 H),
7.63 (d, J = 8.9 Hz, 2 H), 8.11 (d, J = 9.0 Hz, 2 H), 10.26 (s, 1 H).
–1 1
(KBr): 3315, 3061, 2833, 2203, 1657, 1597 cm
. H NMR (400
13
MHz, DMSO-d ): δ = 3.72 (s, 3 H), 6.91 (d, J = 9.1 Hz, 2 H), 7.45–
C NMR (100 MHz, DMSO-d ): δ = 20.6, 55.5, 55.7, 72.7, 97.8,
6
6
7
.51 (m, 5 H), 7.60–7.63 (m, 3 H), 7.73 (d, J = 7.8 Hz, 1 H), 7.74
113.7, 114.1, 114.6, 115.7, 120.1, 121.2, 127.4, 129.3, 129.7,
130.5, 134.9, 160.4, 160.9, 162.0, 167.0.
13
(d, J = 8.2 Hz, 1 H), 8.14–8.16 (m, 2 H), 10.29 (s, 1 H). C NMR
(
100 MHz, DMSO-d ): δ = 55.3, 75.6, 97.8, 113.9, 115.1, 122.9,
25.6, 127.5, 127.6, 128.8, 129.2, 129.9, 130.2, 131.9, 139.0,
56.4, 160.6, 166.5.
-Cyano-2,5-bis(4-methoxyphenyl)-1,3-oxaselenole-2-car-
4-Cyano-N,2,5-tris(4-methoxyphenyl)-1,3-oxaselenole-2-
carboxamide (8e)
6
1
1
4
Yellow solid; yield: 454.1 mg (54%); 212–214 °C (EtOH–1,4-
dioxane). IR (KBr): 3306, 2932, 2835, 2199, 1664, 1607 cm–1. 1H
boxamide (8a)
NMR (400 MHz, DMSO-d ): δ = 3.72 (s, 3 H), 3.75 (s, 3 H), 3.85
6
Pale-yellow solid; yield: 299.5 mg (45%); 184–185 °C (EtOH). IR
(s, 3 H), 6.91 (d, J = 9.0 Hz, 2 H), 7.02 (d, J = 8.9 Hz, 2 H), 7.14 (d,
J = 9.0 Hz, 2 H), 7.48 (d, J = 9.1 Hz, 2 H), 7.63 (d, J = 8.9 Hz, 2 H),
8.11 (d, J = 8.9 Hz, 2 H), 10.23 (s, 1 H). C NMR (100 MHz,
–1 1
(KBr): 3495, 3331, 2935, 2837, 2199, 1691, 1605 cm . H NMR
13
(
400 MHz, DMSO-d ): δ = 3.74 (s, 3 H), 3.84 (s, 3 H), 6.98 (d,
6
J = 9.0 Hz, 2 H), 7.12 (d, J = 9.0 Hz, 2 H), 7.55 (d, J = 8.9 Hz, 2 H),
DMSO-d ): δ = 55.3, 55.5, 55.7, 72.6, 97.8, 113.7, 114.0, 114.1,
114.6, 115.7, 120.1, 122.9, 127.3, 129.7, 130.7, 156.4, 160.4,
160.9, 162.0, 166.8.
6
13
7.91 (s, 1 H), 8.09 (d, J = 9.0 Hz, 2 H), 8.15 (s, 1 H). C NMR (100
MHz, DMSO-d ): δ = 55.4, 55.7, 72.2, 97.7, 113.9, 114.6, 115.7,
6
120.1, 126.7, 129.4, 131.4, 160.2, 160.6, 161.9, 170.4.
©
Georg Thieme Verlag Stuttgart · New York — Synlett 2018, 29, A–D