Synthesis of benzo-ortho-thiazines S-oxides by diels-alder reaction of N-sulfinylanilines with norbornadiene

Article abstract of DOI:10.1134/S1070428013110079

From substituted N-sulfinylanilines acting as dienes in the Diels-Alder reaction with norbornadiene S-oxides of benzo-ortho-thiazines were obtained, which were oxidized into the corresponding S,S-dioxides belonging to the class of hybrid thiazinesulfonami

Full text of DOI:10.1134/S1070428013110079

ISSN 1070-4280, Russian Journal of Organic Chemistry, 2013, Vol. 49, No. 11, pp. 1605−1609. © Pleiades Publishing, Ltd., 2013.
Original English Text © Ya.V. Veremeichik, P.V. Merabov, A.V. Chuiko, O.A. Lodochnikova, V.V. Plemenkov, 2013, published in Zhurnal Organicheskoi Khimii,
2013, Vol. 49, No. 11, pp. 1627−1630.
Synthesis of Benzo-ortho-thiazines S-Oxides by Diels–Alder
Reaction of N-Sulfinylanilines with Norbornadiene
a
a
a
b
a
Ya. V. Veremeichik , P. V. Merabov , A. V. Chuiko , O. A. Lodochnikova , and V. V. Plemenkov
aKant Baltic Federal University, Kaliningrad, 236040 Russia
e-mail: plem-kant@yandex.ru
bArbuzov Institute of Organic and Physical Chemistry, Kazan Scientific Center,
Russian Academy of Sciences, Kazan, Russia
Received March 27, 2013
Abstract—From substituted N-sulfinylanilines acting as dienes in the Diels–Alder reaction with norbornadiene
S-oxides of benzo-ortho-thiazines were obtained, which were oxidized into the corresponding S,S-dioxides belonging
to the class of hybrid thiazinesulfonamide compounds.
DOI: 10.1134/S1070428013110079
Aromatic N-sulfinylamines readily obtainable from
the corresponding anilines and thionyl chloride [1] exhibit
versatile ability in cycloaddition reactions playing the role
of dienophiles [2] and dienes [3] in Diels–Alder reaction.
The adducts of these reactions are compounds of hybrid
structure with benzo-ortho-thiazine and sulfonamide
fragments. Aromatic N-sulfinylamine react as dienes
with strained cycloolefins used as dienophiles similar to
styrenes [4, 5].
a С=С bond in the bicyclic fragment of the molecule,
which opened an opportunity of further functionalization
of adducts to increase the range of potential sulfonamide
substances of a new generation.
The reactions were carried out at the ratio thionylani-
line–norbornadiene 1 : 1.5 without solvent or in benzene
under an argon atmosphere in sealed ampules.At the room
temperature the precipitation of the crystals of the reaction
product started after several days whereas at 80–90°С the
reaction completed in several hours.
We formerly studied the reactions of substituted N-
sulfinylaniline with norbornene, and these adducts were
oxidized to the corresponding benzothiazinesulfonamides
[6].
From para-substituted N-sulfinylanilines and norbor-
nadiene we obtained adducts of the benzo-ortho-thiazine
structure IIa–IIe, whose IR spectra contained character-
istic absorption bands of the N–H (3193–3233 cm–1) and
S=O (1055–1063 cm–1) bonds. In the 1Н NMR spectra the
singlet signal of the proton of the N–H group appears in
In this research we investigated reactions of a series
of N-sulfinylanilines Ia–Ie with norbornadiene aiming at
the preparation of benzothiazinesulfonamides containing
O
:
:
11
O
O
S
4
S
S
4a
N
5
3
N
HN6
1
10b
H
H
2
7
8
10a
10
H
H
H
9
X
Ia_Ie
X
X
IIа_IIe
X = Н (а), Me (b), MeO (c), Cl (d), Br (e).
1605

VEREMEICHIK et al.
1606
the region 8.5–9.2 ppm; the signal system of the aromatic
protons of the adduct of unsubstituted N-sulfinylaniline
IIа is observed as two doublets (1H, 6.90 ppm, J 7.5 Hz;
1H, 6.50 ppm, J 7.4 Hz) and two triplets (1H, 6.78 ppm,
J 7.5 Hz; 1H, 6.68 ppm, J 7.5 Hz), in the spectra of ad-
ducts of the para-substituted N-sulfinylanilines IIb–IIe
this system gives rise to one singlet (1H, 6.88–7.48 ppm)
and two doublets of the АВ system (1H, 6.72–7.43 ppm,
J 8.6–8.8 Hz; 1H, 6.32–6.78 ppm, J 8.3–8.4 Hz). Among
the signals of the bicyclic fragments the characteristic
protons are those at the С=С bond (m, 6.02–6.34 ppm)
and the protons of the endo-methylene bridge (АВ system,
2 J 8.6–9.0 Hz) in the region 0.83–1.91 ppm. The signals
of the node protons Н4а and Н10b appear as two doublets
of the АВ system with 3 J 7.6–9.1 Hz (2.75–3.25 ppm), the
signals of the node protons Н1 and Н4, by two broadened
singlets at 2.40–2.97 ppm. The spatial structure of adducts
we assigned based on the data which had been obtained
in the study of reactions between N-sulfinylanilines with
norbornene [6].
In 1Н NMR spectra of the oxidation products the signal
of the proton of the N–H group is present at 10.2–10.3 ppm;
the system of the signals of aromatic protons of compound
IIIa appears as two doublets (1H, 7.40 ppm, J 7.7 Hz;
1H, 6.94 ppm, J 7.7 Hz) and two triplets (1H, 7.25 ppm,
J 7.4 Hz; 1H, 7.16 ppm, J 7.4 Hz), the similar system
of substituted oxides IIIb–IIIe gives rise to one singlet
(1H, 7.42–7.68 ppm) and two doublets of the АВ system
(1H, 7.22–7.48 ppm, J 8.3–8.5 Hz; 1H, 6.63–6.83 ppm,
J 8.3–8.5 Hz). Characteristically in the 1Н NMR spectra
of all oxidation products the signals of the protons of the
olefin fragment are absent and in the resonance region of
the protons of the bicyclic scaffold a weakly resolved АВ
system of two protons at δ 3.42–3.54 ppm (3 J 3.5–3.7 Hz)
is observed that may be ascribed to an epoxy fragment.
The proton signals of the endo-methylene bridge (АВ
2
system, J 10.6–10.9 Hz) are present in the region
1.08–1.54 ppm. The signals of node protons Н4а and Н10b
are observed as two doublet АВ systems, 3 J 9.0–9.2 Hz
(3.50–3.63 ppm), the signals of node protons Н1 and Н4,
as two broadened singlets in the region 2.20–3.07 ppm
Adducts IIa–IIe were oxidized with hydrogen per-
oxide in acetic acid at room temperature to the corre-
sponding sulfonamides IIIa–IIIe whose structure was
confirmed by the data of IR and NMR spectra and of
XRD analysis. Their spectra contained the characteristic
absorption bands of SO2 group vibrations (1135–1140,
1309–1318 cm–1) and the vibration bands of the N–H
bond (3253–3263 cm–1), the absorption band of the S=O
bond characteristic of initial sulfinamides was absent. It
should be noted that the absorption band of NH bond in
sulfonamides suffered a considerable shift to higher fre-
quencies as compared to the corresponding sulfinamides.
The XRD analysis of a single crystal of compound
IIIa showed that the addition of the diene system of N-
sulfinylaniline to the olefin bond of the norbornadiene
actually occurs from the side of the endo-methylene
bridge, and the epoxidation of the olefin bond also pro-
ceeds from the side of this bridge of the norbornadiene
fragment (see the figure).
The observed route of dienes addition and of epoxida-
tion of compounds with bicyclo[2.2.1]heptene skeleton
from the side of endo-methylene bridge has a fairly
general character (cf.,e.g., [5, 7]).
EXPERIMENTAL
IR spectra were recorded on a spectrophotometer
Bruker Vertex 70 from pellets with KBr. 1Н NMR spectra
in DMSO-d6 were registered on a spectrometer Bruker
Avance IITM-500. Elemental analysis was carried out
on a CHNS-analyzer EuroEA3000. Melting points were
measured using a digital analyzer of melting points Digi-
tal Mel-Temp 3.0.
XRD analysis of crystal IIIa was performed on a dif-
fractometer Bruker SMARTApex II (graphite monochro-
mator, λMoKα 0.71073 Å). The correction for extinction
was carried out semiempirically along SADABS program
[8]. The structure was solved by the direct method ap-
General view of the molecule of (6aS,7S,7aR,8aS,9S,9aS)-
6a,7,7a,8a,9,9a-hexahydro-5H-7,9-methanobenzo[c]oxi-
reno[2’,3’,4,5]benzo[1,2-e][1,2]-thiazine 6,6-dioxide (IIIa)
according XRD data.
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 49 No. 11 2013

SYNTHESIS OF BENZO-ortho-THIAZINES S-OXIDES
1607
plying SHELXS software [9]. Nonhydrogen atoms were
refined first in the isotropic, then in the anisotropic ap-
proximation by SHELXL-97 software [10]. The hydrogen
atoms were placed in the calculated positions and refined
in the rider model. All calculations were carried out us-
ing programs WinGX [11] and APEX2 [12]. The figures
were obtained with the help of PLATON program [13].
J 7.2 Hz), 8.70 s (1Н, Н6). Found, %: С 67.69; Н 5.55;
N 6.13; S 13.71. C13H13NOS. Calculated, %: С 67.50;
Н 5.66; N 6.06; S 13.86.
Compounds IIb–IIe were similarly obtained.
(1R,4S,4aR,10bS)-9-Methyl-1,4,4а,10b-tetrahydro-
6Н-1,4-methanodibenzo[c,e][1,2]thiazine 5-oxide
(IIb) was obtained from 3.1 g (0.02 mol) of reagent Ib.
Yield 4.4 g (88%). White crystals, mp 185–186°С. IR
Crystals of compound IIIa are monoclinic, C13H-
13NO3S. At 20°С a 12.866(4), b 10.469(3), c 8.853(3)
Å, β 105.572(4)°, V 1148.7(6) Е3, Z 4, dcalc 1.522 gг/
cm3, space group P 21/c, μMо 2.81 cm–1. The intensity of
8170 reflections were mesured, 1778 among them had I ≥
2σ. The final values of the divergence factors R 0.0512,
Rw 0.1449. XRD results are deposited in the Cambridge
Crystallographic Data Center (CCDC no. 917575).
1
spectrum, ν, cm–1: 3233 (NH), 1056 (S=O). Н NMR
spectrum, δ, ppm: 1.14 d (1Н, Н11а, J 8.7 Hz), 1,76 d
(1Н, Н11b, J 8.7 Hz), 2.22 s (3Н, СН3), 2.75–3.00 m
(4Н, Н1,4,4а,10b), 6.35 m (2Н, Н2,3), 6.71 d (1Н, Н8,
J 8.6 Hz), 6.92 d (1Н, Н7, J 8.6 Hz), 7.05 s (1Н,
Н10), 8.90 s (1Н, Н6). Found, %: С 68.59; Н 6.15;
N 5.73; S 13.11. C14H15NOS. Calculated, %: С 68.53;
Н 6.17; N 5.71; S 13.07.
N-Sulfinylanilines were synthesized from the corre-
sponding anilines and SOCl2 in benzene by the procedure
[1].
(1R,4S,4aR,10bS)-9-Methoxy-1,4,4а,10b-
tetrahydro-6Н-1,4-methanodibenzo[c,e][1,2]thiazine
5-oxide (IIc) was obtained from 3.4 g (0.02 mol) of re-
agent Ic. Yield 4.8 g (91%). White crystals with a reddish
tint, mp 195–196°С. IR spectrum, ν, cm–1: 3222 (NH),
The reactions of sulfinylanilines with norbornadiene
were carried out by mixing the reagents (thionylani-
line–norbornadiene, 1 : 1.5) in sealed ampules at room
temperature. The formed precipitate was separated by
decanting, washed with petroleum ether, and recrystal-
lized from ethanol.
1
1063 (S=O). Н NMR spectrum, δ, ppm: 1.15 d (1Н,
Н11а, J 8.9 Hz), 1,80 d (1Н, Н11b, J 8.8 Hz), 2.97–3.25 m
(4Н, Н1,4,4а,10b), 3.72 s (3Н, Me), 6.30–6.38 m (2Н, Н2,3),
6.73 d (1Н, Н8, J 8.8 Hz), 6.78 d (1Н, Н7, J 8.5 Hz), 6.92 s
(1Н, Н10), 9.60 s (1Н, H6). Found, %: С 64.20; Н 5.60;
N 6.53; S 12.11. C14H15NOS. Calculated, %: С 64.34;
Н 5.79; N 5.36; S 12.27.
The oxidation of adducts was performed at heating
in a minimal amount of glacial acetic acids using a large
excess of Н2О2. After cooling the solution the product
precipitated as crystals which were recrystallized from
alcohol.
(1R,4S,4aR,10bS)-9-Chloro-1,4,4а,10b-tetrahydro-
6Н-dibenzo[c,e][1,2]thiazine 5-oxide (IId) was obtained
from 3.5 g (0.02 mol) of reagent Id and 2.8 g (0.03 mol)
of norbornadiene. Yield 4.7 g (89%). Light yellow
crystals, mp 250°С (decomp.). IR spectrum, ν, cm–1:
(1R,4S,4aR,10bS)-1,4,4а,10b-Tetrahydro-6Н-1,4-
methanodibenzo[c,e][1,2]thiazine 5-oxide (IIa). A
mixture of 2.9 g (0.02 mol) of N-sulfinylaniline Ia and
2.8 g (0.03 mol) of norbornadiene was charged into a
glass ampule that was sealed. If after mixing the reagents
the complete dissolution did not occur the ampule was
slightly heated till total homogenization. The reaction
completion was visually seen by the growing amount of
precipitated crystals and the reduction in the volume of
the liquid phase in the ampule. On opening the ampule
the precipitate was separated by decanting, washed with
petroleum ether, and recrystallized from warm ethanol.
Yield 4.2 g (90%). White crystals, mp 187–188°С. IR
1
3228 (NH), 1056 (S=O). Н NMR spectrum, δ, ppm:
1.15 d (1Н, Н11а, J 8.8 Hz), 1,73 d (1Н, Н11b, J 8.8 Hz),
2.77–3.05 m (4Н, Н1,4,4а,10b), 6.30 m (2Н, Н2,3), 6.85 d
(1Н, Н8, J 8.4 Hz), 7.17 d (1Н, Н7, J 8.4 Hz), 7.34 s (1Н,
Н10), 9.40 s (1Н, Н6). Found, %: С 58.69; Н 4.55; N 5.23;
S 12.11. C13H12СlNOS. Calculated, %: С 58.75; Н 4.56;
N 5.27; S 12.06.
(1R,4S,4aR,10bS)-9-Bromo-1,4,4а,10b-tetrahydro-
6Н-1,4-methanodibenzo[c,e][1,2]thiazine-5-oxide (IIe)
was obtained from 4.4 g (0.02 mol) of reagent Ie and
2.8 g (0.03 mol) of norbornadiene. Yield 5.2 g (84%).
Light brown crystals, mp 250°С (decomp.). IR spectrum,
1
spectrum, ν, cm–1: 3165 (NH), 1054 (S=O). Н NMR
spectrum, δ, ppm: 0.80 d (1Н, Н11а, J 8.8 Hz), 1.45 d
(1Н, Н11b, J 9.2 Hz), 2.40–2.75 m (4Н, Н1,4,4а,10b), 6.25 m
(2Н, Н2,3), 6.50 d (1Н, Н10, J 7.9 Hz), 6.65 t (1Н, Н9,
J 7.5 Hz), 6.79 t (1Н, Н8, J 7.2 Hz), 6.91 d (1Н, Н7,
1
ν, cm–1: 3229 (N–H), 1055 (S=O). Н NMR spectrum,
δ, ppm: 1.15 d (1Н, Н11а, J 8.8 Hz), 1.72 d (1Н, Н11b,
RUSSIAN JOURNAL OF ORGANIC CHEMISTRY Vol. 49 No. 11 2013

VEREMEICHIK et al.
1608
3.50 d (1Н, Н6а, J 9.1 Hz), 3.72 s (3Н, OCH3), 6.72–6.78
(2Н, Н4,3), 6.88 s (1Н, H1), 9.60 s (1Н, Н5). Found, %:
С 57.34; Н 5.18; N 4.73; S 10.95. C14H15NO4S. Calcu-
lated, %: С 57.32; Н 5.16; N 4.77; S 10.93.
J 8.8 Hz), 2.77–3.05 m (4Н, Н1,4,4а,10b), 6.33 m (2Н, Н2,3),
6.80 d (1Н, Н8, J 8.4 Hz), 7.28 d (1Н, Н7, J 8.4 Hz), 7.48 s
(1Н, Н10), 9.20 s (1Н, Н6). Found, %: С 50.39; Н 3.85;
N 4.53; S 10.41. C14H15BrNOS. Calculated, %: С 50.33;
Н 3.90; N 4.51; S 10.34.
(6aS,7S,7aR,8aS,9S,9aS)-2-Chloro-6a,7,7a,8a,9,9a-
hexahydro-5H-7,9-methanobenzo[c]oxire-
no-[2’,3’,4,5]benzo[1,2-e][1,2]thiazine 6,6-dioxide
(IIId) was obtained from 4.5 g (0.015 mol) of adduct
IId. Yield 3.4 g (75%). White crystals with a reddish tint,
mp 257–258°С. IR spectrum, ν, cm–1: 3223 (N–H), 1318,
(6aS,7S,7aR,8aS,9S,9aS)-6a,7,7a,8a,9,9a-Hexa-
hydro-5H-7,9-methanobenzo[c]oxireno-[2’,3’,4,5]
benzo[1,2-e][1,2]thiazine 6,6-dioxide (IIIa). In glacial
acetic acid was dissolved at heating 3.5 g (0.015 mol)
of adduct IIa. After the homogenization of the solution
the heating was stopped, and slowly 10 mL of Н2О2 was
added. On cooling the precipitated crystals were separated
by decanting and recrystallized from ethanol. Yield 3.0 g
(75%). White crystals, mp 129–131°С. IR spectrum, ν,
cm–1: 3257 (NH), 1310, 1137 (SO2). 1Н NMR spectrum,
1135 (SO2). 1Н NMR spectrum, δ, ppm: 1.08 d (1Н, Н10а
,
J 10.7 Hz), 1.36 d (1Н, Н10b, J 10.7 Hz), 2.60 s (1Н, Н7),
2.90 s (1Н, Н9), 3.36 d (1Н, Н7а, J 3.2 Hz), 3.42 d (1Н,
Н8а, J 2.8 Hz), 3.51 d (1Н, Н9а, J 9.2 Hz), 3.56 d (1Н,
Н6а, J 9.2 Hz), 6.83 d (1Н, Н3, J 8.5 Hz), 7.22 d (1Н,
Н4, J 8.5 Hz), 7.42 s (1Н, Н1), 10.20 s (1Н, H5). Found,
%: С 52.42; Н 4.12; N 4.73; S 10.81. C13H12ClNO3S.
Calculated, %: С 52.44; Н 4.07; N 4.70; S 10.77.
δ, ppm: 1.20 d (1Н, Н10а, J 10.7 Hz), 1.54 d (1Н, Н10b
,
J 10.9 Hz), 2.65 s (1Н, Н7), 3.07 s (1Н, Н9) 3.52 d (1Н,
Н7а, J 3.5 Hz), 3.54 d (1Н, Н8а, J 3.5 Hz), 3.58 d (1Н,
Н9а, J 9.1 Hz), 3.63 d (1Н, Н6а, J 9.0 Hz), 6.94 d (1Н,
Н1, J 7.8 Hz), 7.15 t (1Н, Н2, J 7.5 Hz), 7.25 t (1Н, Н3,
J 7.3 Hz), 7.40 d (1Н, Н4, J 7.6 Hz), 10.20 s (1Н, H5).
Found, %: С 59.29; Н 4.95; N 5.34; S 12.21. C13H13NO3S.
Calculated, %: С 59.30; Н 4.98; N 5.32; S 12.18.
(6aS,7S,7aR,8aS,9S,9aS)-2-Bromo-6a,7,7a,8a,9,9a-
hexahydro-5H-7,9-methanobenzo[c]oxire-
no-[2’,3’,4,5]benzo[1,2-e][1,2]thiazine 6,6-dioxide
(IIIe) was obtained from 5.1 g (0.015 mol) of adduct
IIe. Yield 3.8 g (74%), white crystals, mp 264–265°С.
IR spectrum, ν, cm–1: 1137, 1310 (SO2), 3259 (N–H).
1Н NMR spectrum, δ, ppm: 1.08 d (1Н, Н10а, J 10.6 Hz),
1.35 d (1Н, Н10b, J 10.8 Hz), 2.48 s (1Н, Н7), 2.57 s (1Н,
Н9), 3.34 d (1Н, Н7а, J 3.6 Hz), 3.40 d (1Н, Н8а, J 3.6 Hz),
3.50 d (1Н, Н9а, J 9.2 Hz), 3.58 d (1Н, Н6а, J 9.2 Hz),
6.77 d (1Н, Н3, J 8.4 Hz), 7.35 d (1Н, Н4, J 8.5 Hz), 7.55 s
(1Н, Н1), 10.30 s (1Н, H5). Found, %: С 45.62; Н 3.52;
N 4.07; S 9.41. C13H12BrNO3S. Calculated, %: С 45.63;
Н 3.54; N 4.09; S 9.37.
Compounds IIIb–IIIe were similarly obtained.
(6aS,7S,7aR,8aS,9S,9aS)-2-Methyl-6a,7,7a,8a,9,9a-
hexahydro-5H-7,9-methanobenzo[c]oxire-
no-[2’,3’,4,5]benzo[1,2-e][1,2]thiazine 6,6-dioxide
(IIIb) was obtained from 4.2 g (0.015 mol) of adduct
IIb. Yield 3.2 g (77%). Yellow crystals, mp 187–188°С.
IR spectrum, ν, cm–1: 3223 (N–H), 1320, 1138 (SO2).
1Н NMR spectrum, δ, ppm: 1.06 d (1Н, Н10а, J 10.7 Hz),
1.38 d (1Н, Н10b, J 10.7 Hz), 2.22 s (3Н, С11Н3), 2.54 s
(1Н, Н7), 2.94 s (1Н, Н9), 3.38 d (1Н, Н8а, J 3.8 Hz),
3.42 d (1Н, Н7а, J 3.9 Hz), 3.46 d (1Н, Н6а, J 8.6 Hz),
3.48 d (1Н, Н9а, J 8.7 Hz), 6.72 d (1Н, Н4, J 8.0 Hz),
6.96 d (1Н, Н3, J 7.9 Hz), 7.09 s (1Н, Н1), 9.80 s (1Н,
H5). Found, %: С 60.67; Н 5.42; N 5.03; S 11.61. C14H-
15NO3S. Calculated, %: С 60.63; Н 5.46; N 5.05; S 11.56.
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