Chlorosulfonation of 9-aryloctahydroxanthen-1,8-diones

Article abstract of DOI:10.1080/10426500490494741

The 9-aryloctahydroxanthen-1,8-diones (3, 4-24) were prepared by reaction of cyclohexan-1,3-dione (1) with selected arylaldehydes. The xanthendiones (4-9, 11, 12, 18, 21, 22) were successfully reacted with chlorosulfonic acid, and the crude sulfonyl chlorides were converted into 15 sulfonamides (26-40) for screening as potential pesticides. Attempted chlorosulfonation of the xanthendiones (13-17) was unsuccessful. α-Methylcinnamaldehyde was reacted with cyclohexandione (1) to yield the corresponding xanthendione derivative (23). On the other hand, with o-methoxycinnamaldehyde an impure product formed and the p-methoxy isomer afforded the corresponding 2-arylpyran (25). The NMR spectral data of the compounds are briefly discussed.

Full text of DOI:10.1080/10426500490494741

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Phosphorus, Sulfur, and Silicon
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CHLOROSULFONATION OF 9-
ARYLOCTAHYDROXANTHEN-1,8-
DIONES
Richard J. Cremlyn a & Ghulam Shabbir a
a University of Hertfordshire, Hatfield , England
Published online: 16 Aug 2010.
To cite this article: Richard J. Cremlyn & Ghulam Shabbir (2004)
CHLOROSULFONATION OF 9-ARYLOCTAHYDROXANTHEN-1,8-DIONES, Phosphorus,
Sulfur, and Silicon and the Related Elements, 179:12, 2635-2643, DOI:
10.1080/10426500490494741
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Phosphorus, Sulfur, and Silicon, 179:2635–2643, 2004
ꢀC
Copyright Taylor & Francis Inc.
ISSN: 1042-6507 print / 1563-5325 online
DOI: 10.1080/10426500490494741
CHLOROSULFONATION OF
9-ARYLOCTAHYDROXANTHEN-1,8-DIONES
Richard J. Cremlyn and Ghulam Shabbir
University of Hertfordshire, Hatfield, Hertfordshire, England
(Received April 27, 2004; accepted June 1, 2004)
The 9-aryloctahydroxanthen-1,8-diones (3, 4–24) were prepared by re-
action of cyclohexan-1,3-dione (1) with selected arylaldehydes. The xan-
thendiones (4–9, 11, 12, 18, 21, 22) were successfully reacted with
chlorosulfonic acid, and the crude sulfonyl chlorides were converted
into 15 sulfonamides (26–40) for screening as potential pesticides. At-
tempted chlorosulfonation of the xanthendiones (13–17) was unsuc-
cessful. α-Methylcinnamaldehyde was reacted with cyclohexandione (1)
to yield the corresponding xanthendione derivative (23). On the other
hand, with o-methoxycinnamaldehyde an impure product formed and
the p-methoxy isomer afforded the corresponding 2-arylpyran (25). The
NMR spectral data of the compounds are briefly discussed.
Keywords: 9-Aryloctahydroxanthen-1,8-diones; chlorosulfonation;
sulfonamides
Chlorosulfonic acid is extensively employed as a reagent for the sulfona-
tion and chlorosulfonation of aromatic and heteroaromatic compounds.1
The work described in this article forms part of our previous studies on
the chlorosulfonation of heterocyclic compounds as a route to the syn-
thesis of arylsulfonyl derivatives of potential biological activity.2−5
The chlorosulfonation of dimedione (5,5-dimethylcylohexan-1,3-
dione) derivatives of aromatic aldehydes was studied previously.6 The
work has now been extended to the chlorosulfonation of the anal-
ogous derivatives of cyclohexan-1,3-dione and aromatic aldehydes.
Cyclohexan-1,3-dione (1), like dimedione, is known to be a reagent
for the identification of aldehydes in organic qualitative analysis.7−10
The dione (1;2 moles) reacts with aldehydes (1 mole) by a Michael-type
condensation to yield the 2:1 adducts (2); the latter are readily dehy-
drated by acids, yielding the corresponding octahydroxanthen-1,8-dione
(3, Scheme 1).
Address correspondence to Richard J. Cremlyn,
Colchester, Essex, CO6 IAN, England, UK.
4 Nunns Close, Coggeshall,
2635

2636
R. J. Cremlyn and G. Shabbir
SCHEME 1
The xanthendiones (3) are solids; however, they do not generally form
such well-defined crystals as the analogous dimedione derivatives, and
consequently they are not so widely used in organic qualitative analysis.
Reaction of cyclohexan-1,3-dione with aromatic aldehydes provides
a series of 9-aryloctahydroxanthendiones (3, R Ar), which should be
susceptible to chlorosulfonation by treatment with excess chlorosulfonic
acid because they are essentially alkyl-substituted benzene derivatives
which are known1 to react with chlorosulfonic acid under comparatively
mild conditions. In addition, previous studies have demonstrated that
keto groups are unaffected by treatment with chlorosulfonic acid: thus
hydantoins11 and chalcones12 have been successfully converted into the
corresponding chlorosulfonyl derivatives.
The aromatic aldehydes (1 mole) reacted with cyclohexan-1,3-dione
(2 moles), in boiling aqueous ethanol-piperidine as catalyst to give the
1,2-adducts (2, R Ar), which were dehydrated by heating with ethanol-
concentrated hydrochloric acid under standard conditions,13,14 yielding
the 9-aryloctahydroxanthendiones (3, R Ar). By this procedure, the
xanthendiones (3) were obtained from benzaldehyde (4) and the follow-
ing substituted benzaldehydes: 2ꢁ-methyl (5); 4ꢁ-methyl (6); 2ꢁ-, 3ꢁ-, and
3ꢁ-methoxy (7–9); 4ꢁ-fluoro (10); 3ꢁ-, 4ꢁ-dichloro (11); 2ꢁ-, 4ꢁ-, and 4ꢁ-nitro
(12–14); 2ꢁ- and 4ꢁ-trifluoromethyl (15, 16); and 4ꢁ-dimethylamino (17).
Other analogous derivatives were prepared from thiophen-
2- and 3-carboxaldehyde (18, 19), pyridine-4-carboxaldehyde (20),
biphenyl-4-carboxaldehyde (21), and cinnamaldehyde (22) and
α-methylcinnamaldehyde (23) (Chart 1).
Reaction of cyclohexan-1,3-dione (1) with an equimolar quantity of
p-methoxycinnamaldehyde afforded the pyran derivative (25) (Chart 1).
This product was formed irrespective of the presence or absence of base
(piperidine), which supports the pyran structure. On the other hand, at-
tempted reaction of the dione (1) with o-methoxycinnamaldehyde gave
an impure product (an oil).
The 1H NMR spectra of the 9-aryloctahydroxanthendiones (3)
showed that the tertiary allylic proton (9-H) resonated as relatively
low-field singlet (δ 5.0 approx.) because this proton is deshielded by the
combined effects of the adjacent double bond and the aromatic ring.

Chlorosulfonation
2637
CHART I 9-Aryloctahydroxanthen-1,8-diones and their Sulfonyl Derivatives.
Numbers Under the Y Heading Indicate the Position of the SO2 Y Group.
X
H
X
H
H
H
Y
(4)
(5)
(6)
(7)
(8)
(26)
(27)
(28)
(29)
(30)
(31)
(32)
(33)
(34)
(35)
(36)
(37)
(38)
(39)
(40)
4ꢁ-NMe2
2ꢁ-Me
4ꢁ-Me
2ꢁ-OMe
3ꢁ-OMe
4ꢁ-OMe
4ꢁF
4ꢁ-NHEt
4ꢁ-pyrrolidino
5ꢁ-NMe2
2ꢁ-Me
4ꢁ-Me
2ꢁ-OMe
2ꢁ-OMe
3ꢁ-OMe
3ꢁ-OMe
4ꢁ-OMe
3ꢁ,4ꢁCl2
2ꢁ-NO2
5ꢁ-NMe2
(9)
5ꢁ-NHEt
5ꢁ-piperidino
4ꢁ-NMe2
(10)
(11)
(12)
(13)
(14)
(15)
(16)
(17)
3ꢁ,4ꢁCl2
2ꢁ-NO2
3ꢁ-NO2
4ꢁ-NO2
2ꢁ-CF3
4ꢁ-CF3
4ꢁ-NMe2
4ꢁ-piperidino
5ꢁ-pyrrolidino
5ꢁ-NMe2
4ꢁ-NMe2
4ꢁ-dimethylsulfonamide of (18)
4ꢁ-dimethylsulfonamide of (21)
4ꢁ-dimethylsulfonamide of (22)
(18)
(19)
(20)
(21)
(22)
(23)
2ꢁthienyl
3ꢁthienyl
4ꢁpyridyl
4-Ph.C6H4
PhCH CH
PhCH CMe

2638
R. J. Cremlyn and G. Shabbir
The remaining aliphatic protons generally appeared as a broad mul-
triplet (δ 3.0–1.2); furthermore, relatively low field resonances (δ 2.6,
2.4) could often be clearly identified corresponding to the protons of
the CH2CO and CH2C C moieties, namely the 2- and 4-H protons,
respectively.
Several 9-aryloctahydroxanthen-1,8-diones (4–9, 18, 21, and 22) re-
acted with excess chlorosulfonic acid (10–12 moles) at room tempera-
ture to give the crude sulfonyl chlorides. In the majority of the com-
pounds, the pure sulfonyl chlorides were not isolated (c.f. Cremlyn and
Saunders6). The sulfonyl chlorides were, however, purified and charac-
terized as the alkyl sulfonamide derivatives (Chart 1).
EXPERIMENTAL
Melting points were determined with a Gallenkamp electric apparatus
and are uncorrected. IR spectra were recorded as nujol mulls using a
Perkin Elmer 237 spectrophotometer. 1H NMR spectra were measured
with a Bruker AC 250 spectrometer using tetramethylsilane (TMS) as
internal standard and CDCl3 as solvent. Resonances removed by D2O
treatment are indicated by an asterisk. 13C NMR spectra were recorded
using a Jeol EX 270 instrument. EI mass spectra were obtained with a
V.G. Micromass 16F spectrometer operating at 70 ev.
Preparation of 9-Aryl-1,2,3,4,5,6,7,8-octahydroxanthen-1,
8-diones (3)
Cyclohexane-1,3-dione (5.6 g, 0.05 mole) was dissolved in warm 10%
aqueous ethanol (50 ml), and then a solution of the appropriate ary-
laldehyde (0.025 mole) in ethanol (10 ml) was added followed by piperi-
dine (3 drops). The solution was heated in a steam bath for 10 min.
After cooling in ice water, the crystalline 1,2-adduct (2) separated out,
filtered off, and dried. The product was dissolved in ethanol (30 ml) con-
taining concentrated hydrochloric acid (3 drops), and the solution was
refluxed on the steam bath for 30 min. When the solution was cooled
(ice water), the xanthendione (3) crystallized out and was collected and
dried (vacuum desiccator). By this procedure, the xanthendiones (4–24)
were prepared. The following xanthendiones were novel:
2 ꢀ-Methyl (5)
m.p. 220–222◦C. 1H NMR: δ 7.1–6.8 (m, 4H, Ar H), 4.82 (s, 1H, 9-H),
2.9 (s, 3H, Ar Me), 2.6–2.0 (M, 12H, alip H).

Chlorosulfonation
2639
2 ꢀ-Methoxy (7)
m.p. 221◦C. 1H NMR: δ 7.4–6.78 (m, 4H, Ar H), 4.85 (s, 1H, 9-H), 3.8
(s, 3H, OMe), 2.7 (m, 4H, 2-H), 2.5 (m, 4H, 4-H), 1.8 (m, 4H, 3-H).
4 ꢀ-Fluoro (10)
m.p. 235◦C C19H17O3F requires C, 73.1; H, 5.4. Found: C, 73.0; H,
5.6.
3 ꢀ,4 ꢀ,-Dichloro (11)
m.p. 243–245◦C. C19H16O3Cl2 requires C, 62.8; H, 4.4. Found: C, 63.1;
H, 4.5.
2 ꢀ-Trifluoromethyl (15)
m.p. 235–236◦C. C20H17O3F3 requires C, 66.3; H, 4.7. Found: C, 66.1;
H, 5.0.
4 ꢀ-Trifluoromethyl (16)
m.p. 240–242◦C. C20H17O3F3 requires C, 66.3; H, 4.7. Found: C, 66.0;
H, 4.8.
2 ꢀ-Thienyl (18)
m.p. 218–220◦C. 1H NMR: δ 7.3–6.8 (m, 3H, Ar H), 5.2 (s, 1H, 9-H),
2.65–1.8 (m, 12H, Alip H). MS: 300 (M+).
3 ꢀ-Thienyl (19)
m.p. 208–210◦C. 1H NMR: δ 7.5–6.8 (m, 3H, Ar H), 4.8 (s, 1H, 9-H),
2.6–2.0 (m, 12H, Alip H). MS: 300 (M+).
4 ꢀ-Bipyridyl (21)
m.p. 196–198◦C. 1H NMR: δ 7.6–6.8 (m, 9H, Ar H), 4.82 (s, 1H, 9-H),
2.6 (m, 4H, 2-H), 2.35 (m, 4H, 4-H), 2.0 (m, 4H, 3-H). MS: 370 (M+).
Cinnamaldehyde (22)
m.p. 184–186◦C. C21H20O3 requires C, 78.7; H, 6.2. Found: C, 78.4; H,
6.4. 1H NMR: δ 7.35–7.1 (m, 5H, Ar H), 6.2 (d, 2H, CH CH), 4.4 (s, 1H,
9-H), 2.7–2.0 (m, 12H, alip H). 13C NMR: δ 196.7 (C O), 164.8, 137.2,
131.1 (3 signals, alkenic C), 129.8–115.3 (6 signals, aryl C), 36.9–20.4
(4 signals, alkyl C). MS: 320 (M+).
α-Methylcinnamaldehyde (23)
m.p. 153–155◦C. C22H22O3 requires C, 79.0; H, 6.0. Found: C, 79.3;
1
H, 5.8. H NMR: δ 7.4–7.1 (m, 5H, Ar H), 5.8 (s, H, CH C(Me), 4.5 (s,
1H, 9-H), 2.8 (s, 3H, CH C (Me), 2.6–1.8 (m, 12H, Alip H).

2640
R. J. Cremlyn and G. Shabbir
Terephthaldehyde (24)
m.p. 338–340◦C. C32H30O6 requires C, 75.2; H, 5.9. Found: C, 74.9;
1
H, 6.1. H NMR: δ 8.2–7.4 (m, 4H, Ar H, AAꢁ BBꢁ pattern), 4.9 (s, 2H,
9,9ꢁ-H), 2.6 (m, 4H, 2,2ꢁ-H), 2.4 (m, 4H, 4,4ꢁ-H), 2.0 (m, 4H, 3,3ꢁ-H).
Reaction of Cyclohexan-1,3-Dione (1)
with p-methoxycinnamaldehyde
A solution of cyclohexan-1,3-dione (4.4 g, 0.02 mole) in ethanol (100 ml)
was warmed with p-methoxycinnamaldehyde (3.3 g, 0.02 mole) for
30 min, and the yellow solution was left at room temperature for 1 week.
Cooling in ice-water mixture afforded the 2-(p-methoxy) pyran (25) as
yellow crystals, yield of 4.2 g (80%), m.p. 197–198◦C. C16H15O3 requires
C, 75.3; H, 5.9. Found: C, 75.0; H, 6.1. 1H NMR: δ 7.0–6.8 (m, 4H, Ar H,
AAꢁ BBꢁ pattern), 5.0 (d, 1H, 2-H), 3.7 (s, 3H, OMe), 3.4 (d, 2H, alkenic
H), 2.6–1.2 (m, 6H, alkyl H). MS: 255 (M+).
When the reaction was carried out in the presence of base (piperi-
dine), the identical product (25) was isolated.
Chlorosulfonation of the 9-Aryloctahydroxanthen-1,8-
diones (4–9, 11, 12, 18, 21–22)
The 9-aryloctahydroxanthen-1,8-dione (3, 0.01 mole) was gradually
added, with swirling, to chlorosulfonic acid (14 g, 0.12 mole) at 0◦C. The
solution was left at room temperature until all effervence had ceased
(2–7 days) and was poured onto crushed ice (100 g) with stirring. After
the ice had melted, the product was collected, washed with ice water,
and dried (vacuum desiccator) to yield the sulfonyl chloride. In many
cases, the crude sulfonyl chloride was used and characterized as the
sulfonamide derivative.
Preparation of the Sulfonamides
The 9-(chlorosulfonylaryl)xanthendione (0.01 mole) was gradually
added to a solution of the appropriate amine (0.03 mole) in ethanol
(30 ml) at 0◦C. The mixture was left at room temperature (2–3 days),
added to ice water containing dilute hydrochloric acid, and the precip-
itate filtered off, washed with water, and dried. The solid product was
recrystallized from ethanol to give the sulfonamide derivative.
Compound 26
m.p. 205–206◦C. C21H23NO5S requires C, 62.0; H, 5.65; N, 3.4. Found:
C, 62.3; H, 5.7; N, 3.5. 1H NMR: δ 7.8–7.4 (m, 4H, Ar H, AAꢁ BBꢁ pattern),

Chlorosulfonation
2641
4.85 (s, 1H, 9-H), 2.75 (s, 6H, NMe2), 2.6–1.8 (m, 12H, alip H). MS: 407
(M+).
Compound 27
m.p. 225–227◦C. C21H23NO5S requires C, 62.0; H, 5.65; N, 3.4. Found:
C, 61.6; H, 5.6; N, 3.5. 1H NMR: δ 7.8–7.2 (m, 4H, Ar H, AAꢁ BBꢁ pattern),
5.5∗ (s, 1H, NH), 4.8 (s, 1H, 9-H), 3.0–1.2 (m, 17H, alip H). MS: 407 (M+).
Compound 28
m.p. 189–191◦C. C23H25NO5S requires C, 64.6; H, 5.85; N, 3.3. Found:
C, 64.3; H, 5.8; N, 3.4. 1H NMR: δ 7.85–7.1 (m, 4H, Ar H, AAꢁ BBꢁ
pattern), 4.82 (s, 1H, 9-H), 3.3 (m, 4H, NCH2), 2.62–1.2 (m, 16H, alip
H). 13C NMR: δ 196.5 (C O), 164.7–146 (4 signals, alkenic C), 136–125.4
(6 signals, aryl C), 47.8–20.2 (7 signals, alip C).
Compound 29
m.p. 198–200◦C. C22H25NO5S requires C, 63.6; H, 6.0; N, 3.4. Found:
C, 63.3; H, 5.8; N, 3.5. 1H NMR: δ 7.7–7.0 (m, 3H, Ar H), 4.9 (s, 1H, 9-H),
2.8 (s, 6H, NMe2), 2.3 (s, 3H, Ar-Me), 2.6–1.8 (m, 12H, alip H). MS: 415
(M+).
Compound 30
m.p. 205–206◦C. C22H25NO5S requires C, 63.6; H, 6.0; N, 3.4. Found:
C, 64.0; H, 9.9; N, 3.3. 1H NMR: δ 7.8–7.1 (m, 3H, Ar H), 4.8 (s, 1H, 9-H),
2.8 (s, 6H, NMe2), 2.6–1.9 (m, 12H, alip H), 2.3 (s, 3H, Ar-Me). MS: 415
(M+).
Compound 31
m.p. 230◦C. C22H26NO6S requires C, 61.1; H, 6.0; N, 3.2. Found: C,
60.9; H, 6.2; N, 3.3. 1H NMR: δ 7.8–6.9 (m, 3H, Ar H), 5.0 (s, 1H, 9-H),
4.8∗ (s, 1H, SO2NHEt), 3.8 (s, 3H, OMe), 2.9–1.5 (m, 14H, alip H), 1.2 (t,
3H, CH2Me). 13C NMR: δ 196.6 (C O), 164.7, 160.9 (2 signals, alkenic
C), 133.2–111.1 (6 signals, aryl C), 56.1–14.9 (7 signals, alkyl C).
Compound 32
m.p. 240–242◦C. C25H29NO6S requires C, 63.7; H, 6.1; N, 3.0. Found:
1
C, 63.5; H, 6.0; N, 3.2. H NMR: δ 7.62–7.0 (m, 3H, Ar H), 5.0 (s, 1H,
9-H), 3.9 (s, 3H, OMe), 2.9–1.2 (m, 22H, alip H).
Compound 33
m.p. 135◦C. C22H26NO6S requires C, 61.1; H, 6.0; N, 3.2. Found: C,
60.8; H, 5.9; N, 3.0. MS: 432 (M+).

2642
R. J. Cremlyn and G. Shabbir
Compound 34
m.p. 140–142◦C. C25H29NO6S requires C, 63.7; H, 6.1; N, 3.0. Found:
1
C, 63.5; H, 5.9; N, 2.8. H NMR: δ 8.1–6.2 (m, 3H, Ar H), 4.8 (s, 1H,
9-H), 3.9 (m, 3H, OMe), 3.1–1.4 (m, 22H, alip H). 13C NMR: δ 196.6
(C O), 166.5, 164.4 (2 signals, alkenic C), 135–118 (6 signals, aryl C),
56.5–20.1 (7 signals, alkyl C).
Compound 35
m.p. 208–210◦C. C24H27NO6S requires C, 64.4; H, 3.0; N, 3.1. Found:
1
C, 64.2; H, 2.8; N, 3.4. H NMR: δ 7.8–6.8 (m, 3H, Ar H), 4.85 (s, 1H,
9-H), 3.8 (s, 3H, OMe), 3.3 (m, 6H, CH2NCH2), 2.6–1.7 (m, 16H, alip H).
Compound 36
m.p. 228◦C. C21H21NCl2O5S requires C, 53.6; H, 4.5; N, 3.0. Found:
C, 53.4; H, 4.7; N, 3.1. MS: 473, 469 (M+).
Compound 37
m.p. 206–208◦C. C21H22N2O7S requires C, 56.5; H, 4.9; N, 6.3. Found:
C, 56.3; H, 5.0; N, 6.1. MS: 446 (M+).
Compound 38
m.p. 212◦C. C19H21NO3S2 requires C, 60.8; H, 5.6; N, 3.7. Found: C,
60.6; H, 3.5; N, 4.0. MS: 375 (M+).
Compound 39
m.p. 191–193◦C. C27H27NO5S requires C, 67.8; H, 5.6; N, 2.9. Found:
1
C, 67.6; H, 5.5; N, 3.1. H NMR: δ 7.8–6.8 (m, 8H, Ar H), 4.82 (s, 1H,
9-H), 2.85 (s, 6H, NMe2), 2.5–1.8 (m, 12H, alip H). MS: 477 (M+).
Compound 40
m.p. 188–190◦C. C23H15NO5S requires C, 66.2; H, 3.6; N, 3.35. Found:
C, 66.0; H, 3.9; N, 3.3. 1H NMR: δ 7.3–7.1 (m, 4H, Ar H, AAꢁ BBꢁ pattern),
6.2 (s, 2H, alkenic H), 4.8 (s, 1H, 9-H), 2.9 (s, 6H, NMe2), 2.6–2.0 (m,
12H, alip H). 13C NMR: δ 196.7 (C O), 164.8, 137.2, 131 (3 signals,
alkenic C), 129.8–115.3 (6 signals, aryl C), 36.3–20.4 (4 signals, alkyl
C). MS: 417 (M+).
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Cambridge, 2002).
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Sulfur, and Silicon, 73, 107 (1992).

Chlorosulfonation
2643
[3] R. J. Cremlyn, R. M. Ellam, S. Farouk, S. Graham, and A. Williams, Phosphorus,
Sulfur, and Silicon, 122, 87 (1997).
[4] R. J. Cremlyn, R. M. Ellam, and S. Farouk, Phosphorus, Sulfur, and Silicon, 161,
213 (2000).
[5] R. J. Cremlyn, R. M. Ellam, and S. Farouk, Phosphorus, Sulfur, and Silicon, 178,
1931 (2003).
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