O-Trimethylsilyl-N-phenylsulfonylacetimidate: Synthesis and Structure

Article abstract of DOI:10.1134/S1070363220090091

Abstract: A method for silylation of N-acetylbenzenesulfonamide has been proposed. The structural features of the obtained O-trimethylsilyl-N-phenylsulfonylacetimidate have been studied by means of NMR and IR spectroscopy as well as single-crystal X-ray d

Full text of DOI:10.1134/S1070363220090091

ISSN 1070-3632, Russian Journal of General Chemistry, 2020, Vol. 90, No. 9, pp. 1641–1645. © Pleiades Publishing, Ltd., 2020.
Russian Text © The Author(s), 2020, published in Zhurnal Obshchei Khimii, 2020, Vol. 90, No. 9, pp. 1382–1386.
O-Trimethylsilyl-N-phenylsulfonylacetimidate:
Synthesis and Structure
a
a,
a
a
a
A. Yu. Nikonov , I. V. Sterkhova *, N. A. Kolyvanov , V. Yu. Serykh , and N. F. Lazareva
a
Favorsky Irkutsk Institute of Chemistry, Siberian Branch of Russian Academy of Sciences, Irkutsk, 664033 Russia
e-mail: irina_sterkhova@irioch.irk.ru
*
Received April 30, 2020; revised April 30, 2020; accepted May 11, 2020
Abstract—Amethod for silylation of N-acetylbenzenesulfonamide has been proposed. The structural features of the
obtained O-trimethylsilyl-N-phenylsulfonylacetimidate have been studied by means of NMR and IR spectroscopy
as well as single-crystal X-ray diffraction analysis.
Keywords: N-acylaryl sulfonamides, O-trimethylsilyl-N-phenylsulfonylacetimidate, silylation, silicon-containing
sulfonamides
DOI: 10.1134/S1070363220090091
Silylation of organic compounds is widely applied in
organic and analytical chemistry as well as in materials
science [1–4]. Trisorganylsilyl fragments are efficient
protective groups blocking the O-, N-, and S-reactive
sites [3, 5]. The introduction of a silyl group in organic
compounds alters their reactivity, improves the solubility
in nonpolar solvents, and increases the volatility.
Enhanced volatility allows the use of GLC and mass
spectrometry for isolation and analysis of organic species
reports [10–12]. This study aimed to elaborate a method of
N-acetylbenzenesulfonamide 1 silylation and investigate
the structure of the reaction products.
N-Acetylbenzenesulfonamide 1 was prepared as
describedelsewhere[13].Acylationofbenzenesulfonamide
with acetic anhydride in the presence of a catalytic amount
of ZnCl occurred in bulk and afforded compound 1 in
2
90% yield (Scheme 1).
N-Acetylbenzenesulfonamide reacted with trimethyl-
chlorosilane in benzene medium, the yield of the silylation
product 2 being 68%. The reaction occurred at room
temperature in the presence of triethylamine as hydrogen
chloride acceptor (Scheme 2).
[
3, 6].
A series of organosilicon compounds [R R R SiCl,
R SiNR , and (Me Si) NH] have been used to introduce
1
2 3
3
2
3
2
a silyl group in the compounds structure. О- or N-TMS-
and O,N-bis(TMS) derivatives of carboxylic and sulfonic
acid amides and the related compounds are among the
most efficient and convenient laboratory-scale donors
of trimethylsilyl (TMS) groups [1–3, 7–9]. Silicon-
containing derivatives of N-acylarylsulfonamides
RC(O)N(SiMe )SO Ar are of special interest, yet the
Structure of compound 2 was studied by means of
IR and NMR spectroscopy as well as X-ray diffraction
analysis. The crystal suitable for the latter were obtained
via recrystallization.
According to the X-ray diffraction analysis data,
compound 2 in the crystal exists in the form of
the O-silylated derivative 2b—O-trimethylsilyl-N-
phenylsulfonylacetimidate. Molecular structure of
3
2
data on these compounds have been scarce. To the best of
our knowledge, they have been mentioned only in a few
Scheme 1.
1
641

1642
NIKONOV et al.
Scheme 2.
imidate 2b is shown in Fig. 1, and selected structural
parameters of it are listed in Table 1. A single molecule
of compound 2b was found in the independent part of the
unit cell. Structural analogs of imidate 2b without a SiMe3
group were found in the Cambridge Crystallographic
Data Centre [14–22]. Comparative analysis of those
The amido-imidate tautomeric equilibrium in the
silylated carboxamides is dependent on the nature of
the substituents in the amide moiety as well as external
factors (temperature and solvent) [7, 23–27]. However,
such structures have been earlier studied only using
spectral methods. Herein we investigated the structure of
compound 2 by means of the density functional theory
DFT [B3LYP functional and 6-311G(d) basis set]. The
obtained data revealed the most stable conformers of
the tautomers 2a and 2b as minimums in the potential
energy surface as well as the transition state with the
energy maximum corresponding to the energy barrier of
the 2a→2b transition. Relative energy of tautomer 2a
was 7.9 kcal/mol higher in comparison with tautomer
compounds revealed very close values of the С SN
Ph
bond angle 98.8–100.2° (98.76° for imidate 2b) and
SNC one 120.4–128.6° (122.75° for imidate 2b), yet the
values of the С SNС torsion angle were significantly
Ph
different. The range of the latter covered about 50°
(
123°–176°), being equal to 161.87° for imidate 2b.
Evidently, the difference was due to the presence of
bulky substituents in the structural analogs. For example,
the closest value of the С SNС angle was observed for
Ph
2
b. The simulated energy barrier height was 12 kcal/mol
isopropyl-3-(tert-butylcarbonylamino)-3-cyclohexyl-
relative to tautomer 2a and 19.9 kcal/mol with respect
to tautomer 2b.
2
-methyl-N-(4-nitrophenylsulfonyl)propaneimidate
(163.5°) [24]. The S–N and N=С distances in imidate 2b
In summary, silylation of N-acetylbenzenesulfonamide
afforded O-trimethylsilyl-N-phenylsulfonylacetimidate as
the only product. Its structure was confirmed by means
of X-ray diffraction analysis, IR and NMR spectroscopy,
and quantum-chemical simulation. As in the case of
carboxamides, the amido-imidate tautomerism was
possible for N-acylbenzenesulfonamides [28]. The X-ray
diffraction analysis data suggested the imidate form
of the prepared compound in the solid state. Likely,
were 1.637 and 1.286 Å, respectively, very close to the
corresponding values for the structural analogs (1.633
and 1.285 Å, respectively, on the average) [14–22]. The
adjacent molecules of imidate 2b in the crystal were
linked via CH···O short contacts of the hydrogen atoms
of the MeC(O) and Me Si methyl groups and the phenyl
3
ring with the oxygen atoms of the S=O and Me SiO
3
groups (Fig. 2). The intermolecular bonds length was of
2
.492–2.717 Å.
Fig. 1. General view of molecule of compound 2b in the
crystal.
Fig. 2. Intermolecular short contacts in the crystal of imide 2b.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 90 No. 9 2020

O-TRIMETHYLSYLYL-N-PHENYLSULFONYLACETIMIDATE
1643
Table 1. Selected bond lengths, bond angles, and torsion angles in the molecule of compound 2b
Bond
Si –O
d, Å
Bond angle
φ, deg
111.8(1)
101.3(1)
98.7(1)
111.3(1)
126.7(1)
122.8 (1)
117.3(1)
109.5(1)
112.4(1)
118.3(1)
128.9(1)
Torsion angle
C Si O C
θ, deg
1
1
1
1
1
7
1
1 2
1.713(1)
1.637(1)
1.851(1)
1.850(1)
1.439(1)
1.441(1)
1.765(1)
1.323(1)
1.286(2)
1.388(2)
1.496(2)
O Si С
O Si C
–159.0(1)
–40.5(1)
84.4(1)
–47.9(1)
–161.9(1)
175.2(1)
–5.5(2)
–8.2(2)
172.4(1)
1.4(2)
1
1
1
1
7
1
1
11 2
S –N
C Si O C
1
1
7
1
1
3
2
1
1 2
Si –C
N S C
O S N C
1
7
1
1
1
3
1
11 2
Si –C
O Si C
O S N C
1
2
2
1
3
1
1
22
1
S –O
C O Si
C S N C
1
3
2
1
1
1
1 2
S –O
C N S
S N C O
1
3
3
1
2
1
1
1
1
2
10
1
S –C
O S O
S N C C
1
2
2
2
1
1
1 2
O –C
O S N
Si O C N
1
3
1
1
1 2 10
N –C
O S N
Si O C C
3
4
1
2
1
3 4 5 6
C –C
N C O
C C C C
2
10
1
2
10
1 1 3 4
C –C
N C C
N S C C
129.6(1)
O-trimethylsilyl-N-phenylsulfonylacetimidate was
formed via the substitution of the imidate proton with
the trimethylsilyl group and was a kinetically as well as
thermodynamically favorable reaction product.
dissolution of the benzenesulfonamide precipitate and the
formation of colorless low-viscous solution (10 min).After
that, the mixture was heated at the same temperature at
stirring during 10 min and then the pressure was reduced
to ~10–15 mmHg, the temperature being gradually raised
to 60–65°C. The mixture was kept at those temperature and
pressure during 15 min, and the residue was cooled to room
temperature. ~1.36 g of compound 1 was obtained (yield
EXPERIMENTAL
NMR spectra of a solution in CDCl were recorded
3
1
using a Bruker DPX-400 spectrometer [400.1 ( H), 100.6
13
29
(
C), and 79.5 MHz ( Si)] with HMDS and cyclohexane as
~90%). Spectral parameters of the obtained compound were
internal references. IR spectra were recorded using a Bruker
Vertex 70 spectrometer. X-ray diffraction analysis was
performed using a Bruker D8Venture diffractometer (MoKα
radiation, λ= 0.71073 Å) in the φ- and ω-scanning mode.The
structure was solved and refined via a direct method using
SHELX software suite [29]. The absorption was accounted
for using SADABS software. The non-hydrogen atoms were
refined under anisotropic approximation using SHELX
software [29]. The crystallographic data for compound 1
were deposited at the Cambridge Crystallographic Data
Centre (CCDC 1947408). Quantum-chemical simulation
was performed using GAUSSIAN-09 software suite [30].
identical to the reference ones [31].
О-Trimethylsilyl-N-phenylsulfonylacetimidate (2b).
Amixture of 0.5 g (4.62 mmol) of trimethylchlorosilane and
5
(
(
mL of benzene was slowly added to a solution of 0.91 g
4.56 mmol) of N-acetylbenzenesulfonamide 1 and 0.5 g
5 mmol) of triethylamine in 15 mL of benzene at vigorous
stirring. The obtained mixture was stirred during 3 h at room
temperature; the precipitate was filtered and washed with
20 mL of benzene; the solvent was evaporated off. The
obtained yellowish transparent residue was distilled in
vacuum. Yield 68% (0.84 g), bp 185°С (3–4 mmHg). IR
–1
spectrum (KBr), ν, cm : 757, 784, 851, 1039, 1095, 1162,
The crystals of compound 2b were colorless,
prismatic, 0.40×0.50×0.50 mm, C H NO SSi, М
1
1255, 1333, 1597, 1727, 2961, 3068. H NMR spectrum,
1
1
17
3
δ, ppm: 0.22 s [9H, (CH ) Si], 2.49 s [3H, CH C(O)],
3 3
13
3
2
71.40, monoclinic crystal system, space group P2 /c,
1
7
–
1
.5–7.9 m (5H, PhSO2). C NMR spectrum, δ , ppm:
C
θmin/θmax = 2.33/30.12, T = 100 K, a = 9.8204(4),
b = 8.1281(3), c = 17.0421(8) Å, β = 94.249(2)°, V =
o
m
0.42 (CH Si), 22.16 [CH C(O)], 126.45 (C ), 128.67 (C ),
3
3
p
i
29
32.36 (C ), 141.73 (C ), 174.12 [CH C(O)]. Si NMR
3
3
3
1
356.6(1) Å , Z = 4, d = 1.329 g/cm , F(000) = 576,
calc
–
1
spectrum: δSi 27.0 ppm. Found, %: C 49.12; H 6.27; N
.05; S 11.67; Si 10.49. C H NO SSi. Calculated, %:
μ = 0.323 mm . 36439 reflections were collected
including 3977 independent, 158 parameters were refined,
5
11
17
3
C 48.68; H 6.31; N 5.16; S 11.81; Si 10.35.
R = 2.95, R = 0.0376 (over all reflections), goodness of
w
2
3
fit over F 1.045, Δρmax/Δρmin = 0.341/–0.399 e/Å .
FUNDING
N-Acetylbenzenesulfonamide (1).Amixture of 1.20 g
7.63 mmol) of benzenesulfonamide, 1 g (9.8 mmol, excess)
This study was financially supported by the Russian
Foundation for Basic Research (project no. 18-33-00368-mol_a)
and performed using the equipment of the Baikal Analytical
Center for Collective Usage, Siberian Branch, RAS.
(
of acetic anhydride, and 0.05 g of ZnCl was heated on a
2
water bath at 40–45°C with vigorous stirring until complete
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 90 No. 9 2020

1644
NIKONOV et al.
16. Anugu, R.R. and Chegondi, R., J. Org. Chem., 2017,
CONFLICT OF INTEREST
vol. 82, no. 13, p. 6786.
No conflict of interest was declared by the authors.
https://doi.org/10.1021/acs.joc.7b00936
REFERENCES
1
1
7. Peng, J., Cui, H., and Chen, J.C., Sci. China. Chem.,
2011, vol. 54, p. 81.
1
. Kashutina, M.V., Ioffe, S.L., and Tartakovskii, V.A.,
Russ. Chem. Rev., 1975, vol. 44, no. 9, p. 1620.
https://doi.org/10.1070/RC1975v044n09ABEH002373
https://doi.org/10.1007/s11426-010-4137-2
8. Nikolaev, V., Hennig, L., Sieler, J., Rodina, L.,
2
. Mizhiritskii, M.D. and Yuzhelevskii, Yu.A., Russ.
Chem. Rev., 1987, vol. 56, no. 4, p. 355.
https://doi.org/10.1070/RC1987v056n04ABEH003276
Schulze, B., and Nikolaev, B., Org. Biomol. Chem.,
2
005, vol. 3, no. 22, p. 4108.
https://doi.org/10.1039/b508317f
3
4
5
6
. Look, G., Silylating Agents, Buchs: Fluka Chemie AG,
1
2
2
9. Shen, R. and Huang, X., J. Org. Chem., 2007,
vol. 72, no. 10, p. 3961.
1
995.
. Auner, N. and Weis, J., Organosilicon Chemistry From
Molecules to Materials, Weinheim: VCH, 1994.
https://doi.org/10.1021/jo070239z.
0. Dabbagh, H.A., Modarresi-Alam, A.R., Tadjarodi, A., and
Taeb, A., Tetrahedron, 2002, vol. 58, no. 13, p. 2621.
https://doi.org/10.1016/S0040-4020(02)00130-8
. Greene, T.W. and Wuts, P.G.M., Protective Groups in Or-
ganic Synthesis, New York: John Wiley and Sons, 1999.
. Splitter, J.S. and Turecek, F., Applications of Mass Spec-
trometry to Organic Stereochemistry, Weinheim: VCH,
1. Nguyen, H.V., Matsubara, R., and Kobayashi, S., Angew.
Chem. Int. Ed., 2009, vol. 48, no. 32, p. 5927.
https://doi.org/10.1002/anie.200900309
1
994.
7
. Klebe, J.F., Acc. Chem. Res., 1970, vol. 3, no. 9, p. 299.
https://doi.org/10.1021/ar50033a003
22. Matsubara, R., Berthiol, F., and Kobayashi, S., J. Am.
Chem. Soc., 2008, vol. 130, no. 6, p. 1804.
https://doi.org/10.1021/ja077054u
8
. Verboom, W., Visser, G.W., and Reinhoudt, D.N.,
Synthesis, 1981, no. 10, p. 807.
https://doi.org/10.1055/s-1981-29605
2
3. Bassindale, A.R. and Posner, T.B., J. Organomet.
Chem., 1979, vol. 175, no. 2, p. 273.
9
. Gihani, M.T. and Heaney, H., Synthesis, 1998, no. 4,
p. 357.
https://doi.org/10.1055/s-1998-2043
https://doi.org/10.1016/S0022-328X(00)84548-9
2
4. Jancke, H., Engelhardt, G., Wagner, S., Dirnens, W.,
Herzog, G., Thieme, E., and Rühlmann, K., J. Organomet.
Chem., 1977, vol. 134, no. 1, p. 21.
1
0. Shinichi, I. and Iwao, O., J. Organometal. Chem., 1979,
vol. 169, no. 2, p. 171.
https://doi.org/10.1016/S0022-328X(00)81156-0
https://doi.org/10.1016/S0022-328X(00)93609-X
1
1. Iwao, O., Shinichi, I., and Yoichiro, N., J. Chem.
2
2
2
5. Fukui, M., Itoh, K., Ishii, Y., J. Chem. Soc. Perkin
Soc. Chem. Commun., 1974, no. 20, p. 826.
Trans. 2, 1972, no. 9, p. 1043.
https://doi.org/10.1039/c39740000826
https://doi.org/10.1039/P29720001043
1
1
1
1
2. Gordetsov, F.S., Vostokov, I.A., Dergunov, Yu.I., and
Mushkin, Yu.I., Zh. Obshch. Khim., 1974, vol. 44,
no. 11, p. 2456.
6. Albanov, A.I., Larin, M.F., Pestunovich, V.A., Voron-
kov, M.G., Kramarova, E.P., and Baukov, Yu.I., Zh.
Obshch. Khim., 1981, vol. 51, no. 2, p. 488.
3. Reddy, C.R., Mahipal, B., and Yaragorla, S.R., Tetrahedron
Lett., 2007, vol. 48, no. 42, p. 7528.
7. Otter, J.C., Adamson, C.L., Yoder, C.H., and Rhein-
gold, A.L., Organometallics, 1990, vol. 9, no. 5, p. 1557.
https://doi.org/10.1021/om00119a030.
https://doi.org/10.1016/j.tetlet.2007.08.048
4. Deng, H., Han, T., Zhao, E., Kwok, R.T.K., Lam, J.W.Y., and
Tang, B.Z., Polym. Chem., 2016, vol. 7, no. 36, p. 5646.
https://doi.org/10.1039/C6PY01337F
28. Padrela, L., Zeglinski, J., and Ryan, K., Cryst. Growth
Des., 2019, vol. 19, no. 2, p. 613.
https://doi.org/10.1021/acs.cgd.8b01015
5. Yao, Z.-J., Li, K., Zhang, J.-Y., Wang, Y., and Deng, W.,
Inorg. Chim. Acta, 2016, vol. 450, p. 118.
29. Sheldrick, G.M., Acta Crystallogr. (A), 2008, vol. 64,
p. 112.
https://doi.org/10.1016/j.ica.2016.05.032
https://doi.org/10.1107/S0108767307043930
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 90 No. 9 2020

O-TRIMETHYLSYLYL-N-PHENYLSULFONYLACETIMIDATE
1645
3
0. Frisch, M.J., Trucks, G.W., Schlegel, H.B., Scuseria, G.E.,
Robb, M.A., Cheeseman, J.R., Scalmani, G., Barone, V.,
Mennucci, B., Petersson, G.A., Nakatsuji, H., Caricato, M.,
Li, X., Hratchian, H.P., Izmaylov, A.F., Bloino, J., Zheng, G.,
Sonnenberg, J.L., Hada, M., Ehara, M., Toyota, K., Fuku-
da, R., Hasegawa, J., Ishida, M., Nakajima, T., Honda, Y.,
Kitao, O., Nakai, H., Vreven, T., Montgomery, J.A., Jr.,
Peralta, J.E., Ogliaro, F., Bearpark, M., Heyd, J.J., Broth-
ers, E., Kudin, K.N., Staroverov, V.N., Kobayashi, R., Nor-
mand, J., Raghavachari, K., Rendell, A., Burant, J.C., Iy-
engar, S.S., Tomasi, J., Cossi, M., Rega, N., Millam, J.M.,
Klene, M., Knox, J.E., Cross, J.B., Bakken, V., Adamo, C.,
Jaramillo, J., Gomperts, R., Stratmann, R.E., Yazyev, O.,
Austin, A.J., Cammi, R., Pomelli, C., Ochterski, J.W.,
Martin, R.L., Morokuma, K., Zakrzewski, V.G.,
Voth, G.A., Salvador, P., Dannenberg, J.J., Dapprich, S.,
Daniels, A.D., Farkas, O., Foresman, J.B., Ortiz, J.V.,
Cioslowski, J., and Fox, D.J., Gaussian 09, Revision A.01,
Gaussian, Inc., Wallingford CT, 2009.
31. Taylor, J.E., Jones, M.D., Williams, J.M.J., and Bull, S.D.,
J. Org. Chem., 2012, vol. 77, no, p. 2808.
https://doi.org/10.1021/jo202647f
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 90 No. 9 2020