Poly(N,N'-dichloro-N-ethyl-benzene-1, 3-disulfonamide) and N,N,N',N'-Tetrachlorobenzene-1,3-disulfonamide as novel catalytic reagents for synthesis of Bis-indolyl, Tris-indolyl, Di(bis-indolyl), Tri(bis-indolyl) and Tetra(bis-indolyl) methanes under solid-state, solvent and water conditions

Article abstract of DOI:10.1590/s0103-50532010000200002

Easy and rapid preparation of bis-indolyl, tris-indolyl, di(bis-indolyl), tri(bis-indolyl) and tetra(bis-indolyl) methanes from indole with various aldehydes and ketones using poly (N,N'-dichloro-N-ethyl-benzene-1,3- disulfonamide) [PCBS] and N,N,N',N'-tetrachlorobenzene-1,3-disulfonamide [TCBDA] as novel catalysts under various conditions are here described.

Full text of DOI:10.1590/s0103-50532010000200002

J. Braz. Chem. Soc., Vol. 21, No. 2, 193-201, 2010.
Printed in Brazil - ©2010 Sociedade Brasileira de Química
0103 - 5053 $6.00+0.00
Poly(N,N’-dichloro-N-ethyl-benzene-1, 3-disulfonamide) and N,N,N’,N’-
Tetrachlorobenzene-1,3-disulfonamide as Novel Catalytic Reagents for Synthesis
of Bis-indolyl, Tris-indolyl, Di(bis-indolyl), Tri(bis-indolyl) and Tetra(bis-indolyl)
Methanes under Solid-State, Solvent and Water Conditions
Ramin Ghorbani-Vaghei*,a and Hojat Veisia,b
aDepartment of Organic Chemistry, Faculty of Chemistry, Bu-Ali Sina University, 65174, Hamadan, Iran
bDepartment of Chemistry, Payame Noor University, Songhor, Kermanshah, Iran
Descreve-se a preparação fácil e rápida de bis-indolil, tris-indolil, di(bis-indolil), tri(bis-indolil)
e tetra(bis-indolil) metanos a partir de indole com diferentes aldeídos e cetonas, sob diferentes
condições reacionais, usando poly(N,N´-dicloro-N-etil-benzeno-1,3-disulfonamida), [PCBS], e
N,N,N´,N´-tetraclorobenzeno-1,3-disulfonamida, [TCBDA], como novos catalizadores.
Easy and rapid preparation of bis-indolyl, tris-indolyl, di(bis-indolyl), tri(bis-indolyl) and
tetra(bis-indolyl) methanes from indole with various aldehydes and ketones using poly (N,N’-
dichloro-N-ethyl-benzene-1,3-disulfonamide) [PCBS] and N,N,N’,N’-tetrachlorobenzene-1,3-
disulfonamide [TCBDA] as novel catalysts under various conditions are here described.
Keywords: TCBDA, PCBS, bis(indolyl)methanes, catalytic reagents
Introduction
(SSA),25 TiO2,26 (NH4)2HPO4,27 acidic ionic liquid,28
NaBF4,29 metal hydrogen sulfates,30 tetrabutylammonium
tribromide,31 superacid SO42-/TiO2,32 NaHSO4/ionic
liquid,33 NBS,34 Ph3CCl,35 H3PW12O40,36 LiClO4,37 Zr(DS)4,38
and Bi(NO3)3·5H2O.39
Indole derivatives are widely distributed in nature and
are known to possess broad spectrum of biological and
pharmaceutical activities.1 Bis(indolyl)methanes are found
in cruciferous plants and are known to promote beneficial
estrogen metabolism2 and induce apoptosis in human cancer
cell. Thus, the development of facile and environmental
friendly synthetic methods for the preparation of these
compounds constitutes an active area of investigation in
pharmaceutical and organic synthesis.3-5
Synthetically the reaction of 1H-indole with aldehydes
or ketones produces azafulvenium salts that react further
with a second 1H-indole molecule to form bis(indol-3-
yl)methanes.6 In recent years, synthesis of this class of
molecules under mild conditions have been reported, with
promoters such as montmorillonite clay K-10,7 trichloro-
1,3,5-triazine,8 AlPW12O40,9 sodium dodecyl sulfate
(SDS),10 ZrCl4,11 H2NSO3H,12 I2,13 zeolites,14 bentonite,15
In(OTf)3/ionic liquid,16 CuBr2,17 Dy(OTf)3/ ionic liquid,18
HClO4-SiO2,19 InCl3,20 MW/ Lewis acids (FeCl3, BiCl3,
InCl3, ZnCl2, CoCl2),21 NaHSO4 and Amberlyst-15,22
sulfated zirconia,23 ZrOCl2/SiO2,24 silica sulfuric acid
Result and Discussion
In continuation of our interest in the synthesis of
N-halo sulfonamide and application of these reagents in
organic synthesis,40-43 we report the synthesis of poly (N,N’-
dichloro-N-ethyl-benzene-1,3-disulfonamide) [PCBS]
and N,N,N’,N’-tetrachlorobenzene-1,3-disulfonamide
[TCBDA] as novel catalytic reagents in organic reactions
(Scheme 1).
Many of the methods described above involve the
use of expensive reagents, high catalyst loading, long
reaction times and environmentally hazardous reagents.
Therefore, we studied the use of poly (N,N’-dichloro-
N-ethyl-benzene-1,3-disulfonamide) and N,N,N’,N’-
tetrachlorobenzene-1,3-disulfonamide as novel catalysts
in the electrophilic substitutions of indole with a variety of
aldehydes and ketones under (i) solvent-free, (ii) solvent
conditions (H2O and EtOH) to afford bis(indolyl)methanes
(Scheme 1).
*e-mail: rgvaghei@yahoo.com

194
Poly(N,N’-dichloro-N-ethyl-benzene-1, 3-disulfonamide) and N,N,N’,N’-Tetrachlorobenzene-1,3-disulfonamide
J. Braz. Chem. Soc.
Scheme 1.
Since TCBDA and PCBS contain chlorine atoms which
their reduced pollution, low cost, simplicity in process and
handling. Therefore, we decided to test this reaction under
solvent-free conditions (grinding) with these reagents. We
found that the reaction could be rapid with excellent yield,
(98%, entry 1) using N,N,N’,N’-tetrachlorobenzene-1,3-
disulfonamide [TCBDA] (1 min) and using poly (N,N’-
dichloro-N-ethyl-benzene-1,3-disulfonamide) [PCBS]
(1.5 min). In comparison to the reported methods, TCBDA
and PCBS under solvent-free conditions were found to be
efficient catalysts in terms of handling, temperature, yield
and reaction times.
These results promoted us to investigate the scope
and the generality of these new protocols for various
aldehydes and ketones under optimized conditions.
As shown in Table 1, a series of aromatic, aliphatic
and heterocyclic aldehydes underwent electrophilic
substitution reaction with indole smoothly to afford a
wide range of substituted bis(indolyl)methanes in good
to excellent yields. The electron deficiency and nature of
the substituents on the aromatic ring effect the conversion
are attached to nitrogen atoms, it is also possible that they
release Cl+ in situ which can act as Lewis acid to activate
the carbonyl oxygen to form the bis-indole derivatives.
Initially, we carried out the reaction of indole
with benzaldehyde in the presence catalytic amount
of N,N,N’,N’-tetrachlorobenzene-1,3-disulfonamide
(TCBDA) in EtOH at room temperature. After 5 min the
reaction completed with good yield (96%).
The applicability of the present methodology is further
extended by performing the reaction in an aqueous media.
In this reaction, we also found that, water in the presence
of 5 mol% CTAB (N-cetyl-N,N,N-trimethylammonium
bromide) as surfactant is essential for this reaction using
TCBDA at room temperature. However, this process is
green, environmentally friendly, clean, and could be carried
out easily at room temperature without undesirable side
reactions.
In recent years, there has been an increasing interest
in reactions that proceed in the absence of solvents due to
HN
CHO
Condition A
Condition B
Condition C
2
+
N
N
N
N
H
H
H
H
Condition A: TCBDA or PCBS, EtOH, 40 °C, 30 min, 95%
Condition B: TCBDA or PCBS, solid-state, grinding, r.t., 10 min, 96%
Condition C: TCBDA,CTAB, H2O, 100 °C, 120 min, 90%
45
method A: 70 °C, 30 min, 90%
HN
O
O
method B: r.t. 10 min, 96%
2
+
N
method C: 100 °C, 200 min, 70%
N
H
H
N
N
H
O
H
a
Scheme 2.

Vol. 21, No. 2, 2010
Ghorbani-Vaghei and Veisi
195
Table 1. Synthesis of bis(indolyl)methanes by the reaction of indole with aldehydes and ketones in various conditions
Entry
Carbonyl compound
TCBDA (method A) PCBS (method A) TCBDA (method B) PCBS (method B) TCBDA (method C)
time/min yield (%)a time/min yield (%)a time/min yield (%)a time/min yield (%)a time/h yield (%)a
9011
8011
CHO
1
2
5
96
92
10
15
90
90
1
98
96
1.5
2
98
96
2
10
1.5
2.5
3
5
98
10
95
1
99
2
98
3
8911
4
5
6
8
96
92
89
12
15
16
90
87
85
1
2
98
92
95
1.5
2
96
92
90
4
7811
7536
8035
Br
CHO
15
15
3.5
3.5
Cl
CHO
1.5
2.5
7
10
96
20
90
1
96
2
96
2
8235
8
25
15
20
90
92
90
30
20
30
80
90
85
2.5
1
92
96
98
2.5
2
90
96
96
4
2
5
7025a
7911
7035
O
CHO
9
10
1
2
11
25
90
30
85
2
97
2-3
97
4
7035
12
13
30
25
78
95
40
35
75
90
2.5
2
96
95
3
4
96
94
5
7513
7211
4.5
14
15
2
92
85
5
90
80
1
4
98
90
2
6
96
90
2
6
8236
7013
S
CHO
70
85
16
17
18
120
100
110
80
85
78
120
100
120
75
85
70
4
4.5
5
90
85
80
6
5
6
90
80
80
9
7
6
6536
7511
7011
O
a Products were characterized from their physical properties, comparison with authentic samples and by spectroscopic methods.
rate; aromatic aldehydes having electron-withdrawing
groups on the aromatic ring (Table 1, entries 10,11) react
slower than electron-donating groups (Table 1, entries
4, 8, 9, 12). Furthermore, unsaturated aldehydes, such
as cinnamaldehyde, give the corresponding bis(indolyl)
methanes without polymerization or halogenation under the
above reaction conditions. Ketones required longer reaction
times, which is most probably due to the electron-donating
and steric effects of the methyl group.
This reaction was further explored for the synthesis
of tri-indolylmethane by the condensation of indol-3-
carbaldehyde or isatin with two equivalents of indole under
similar conditions with our methods in good to high yields
(Scheme 2 and 3).
Selective condensation of a dialdehyde, i.e.,
terephthaldialdehyde to the corresponding bis-indolyl
methane was achieved by controlling the molar ratio of
indole (Scheme 3). The results showed that addition of 2

196
Poly(N,N’-dichloro-N-ethyl-benzene-1, 3-disulfonamide) and N,N,N’,N’-Tetrachlorobenzene-1,3-disulfonamide
J. Braz. Chem. Soc.
CHO
2-methoxyphenyl-3,3-bis(indolyl)methane in first run (in
solvent condition), which gave the corresponding product
in 98% isolated yield (Table 1, entry 3), the N,N’-dichloro
benzene-1,3-disulfonamide (TCBDA) catalyst was
subjected to a second run reaction from which it gave the
product in 85% yield; the average chemical yield for four
consecutive runs was 60%. The reusability of catalysts are
shown in Figure 1.
2
N
H
method A, B and C
90-92%
N
N
H
H
CHO
CHO
b
H
H
N
N
4
N
H
method A, B and C
95-98%
The chemo selectivity of the present methods is also
demonstrated by competitive reactions of indol with
arylaldehydes in the presence of aliphatic ones and ketones.
For example, when a 1:1 mixture of benzaldehyde and
propionaldehyde was allowed to react with two equivalents
ofindoleinthepresenceofTCBDAandPCBSundervarious
conditions, it was found that the arylaldehydes was chemo
selectively converted to the corresponding bis(indolyl)
methane but the aliphatic ones was converted slightly.
Also, in an equimolar mixture arylaldehyde and ketone,
only arylaldehyde was converted to the corresponding
bis(indolyl)methane, whereas ketone remained (Scheme 7).
The reaction was clean and the products were obtained in
high yields without the formation of any side products such
as N-alkylated products.
In conclusion, we have introduced the novel catalytic
reagents poly (N,N’-dichloro-N-ethyl-benzene-1,3-
disulfonamide) [PCBS] and N,N,N’,N’-tetrachlorobenzene-
1,3-disulfonamide [TCBDA] for the efficient preparation
of bis-indolyl, tris-indolyl, di(bis-indolyl), tri(bis-indolyl)
and tetra(bis-indolyl) methanes from indole with various
aldehydes and ketones in ethanol, water and in solid-state
conditions at room temperature with excellent yields.
This method is applicable to a wide range of aldehydes,
including aromatic, aliphatic, a,b-unsaturated, heterocyclic
substrates, and ketones. In addition, efficiency, mild reaction
conditions, easy work up, simplicity and chemoselectivity
of this protocol provide a fast, green, and low cost procedure
for the synthesis of these compounds.
N
H
N
H
c
Scheme 3.
equivalents of indole to terephthaldialdehyde, gives (b) in
good yield under various conditions (Scheme 3). Treatment
of 4 equivalents of indole with terephthaldialdehyde
gives the corresponding di(bis-indolyl methanes), (c)
in excellent yield at room temperature under various
conditions.38
This reaction was further explored for the synthesis of
tri(bis-indolyl)methane (e) and tetra(bis-indolyl)methanes
(g, h) as new triarylmethanes, by the condensation of
aldehyde (d) with 6 equivalents indole and aldehydes (f,
h) with 8 equivalents indole under similar condition (reflux
in DMSO) in high yields (Scheme 4 and 5).
3-Substituted indoles were examined for this reaction
under the above reaction conditions with aldehydes
(Scheme 6). Since the more active site (C-3) in indole was
blocked in this case electrophilic substitution took place at
C-2 in indole giving the corresponding bis(indolyl)methane
in high yield under various conditions. The results were
summarized in Table 2.
Our experiments also indicated that TCBDA and PCBS
were reusable catalysts and after four runs, the catalytic
activities of the reagents were almost the same as those
of fresh catalysts. Thus, after the successful synthesis of
H
H
N
N
CHO
O
O
O
CH2
6
O
NH
CH2
CH2
N
CH2
H
CHO
DMSO/ 100°C / 10 min
PCBS/ 95%
CH2
O
NH
H2C
TCBDA/ 98%
O
OHC
HN
d
HN
e
Scheme 4.

Vol. 21, No. 2, 2010
Ghorbani-Vaghei and Veisi
197
HN
NH
CHO
O
NH
O
CHO
8
N
H
H
O
N
O
O
O
DMSO/100°C / 15 min
PCBS/ 90%
OHC
N
H
O
TCBDA/ 96%
O
HN
CHO
NH
HN
f
g
NH
HN
H
N
OHC
O
NH
O
OHC
O
8
O
N
H
O
O
DMSO/100°C / 15 min
PCBS/ 90%
TCBDA/ 96%
HN
O
N
H
CHO
CHO
O
NH
HN
h
I
Scheme 5.
Table 2. The reaction of aromatic aldehydes with 3-substituted indoles under various conditions
Condition A
Condition B
Condition C
Entry
Carbonyl compound
Indole
Product
time/min yield (%)a time/min yield (%)a time/min yield (%)a
HOOC
COOH
n
n
HOOC
N
N
H
1
30
30
95
92
10
10
96
90
120
150
9013
H
N
H
OMe
n=3
HOOC
COOH
COOH
N
H
N
H
2
8013
N
H
Me
N
H
N
H
CHO
3
4
25
60
96
75
5
90
70
100
180
8525
N
H
N
H
N
H
10
5044
N
H
NH
a Products were characrerized from their physical properties, comparison with authentic samples and by spectroscopic methods

198
Poly(N,N’-dichloro-N-ethyl-benzene-1, 3-disulfonamide) and N,N,N’,N’-Tetrachlorobenzene-1,3-disulfonamide
J. Braz. Chem. Soc.
R/
R/
/
R
Condition A
Condition B
Condition C
2
+
RCHO
N
N
N
H
H
H
R
Condition A: TCBDA or PCBS, EtOH
Condition B: TCBDA or PCBS, solid-state, grinding, r.t.
Condition C: TCBDA,CTAB, H2O, 100 °C
Scheme 6.
Figure 1. Reusability of catalysts. Conditions: TCBDA (0.1 mmol) or PCBS (0.1 g), indole (4 mmol), 2-methoxybenzaldehyde (2 mmol), EtOH (5 mL)
and time (10 min).
CHO
O
+
+
O
N
N
H
N
H
H
100%
100%
100%
95%
98%
90%
method A:
method B:
method C:
CHO
+
+
N
N
N
N
H
N
H
H
H
H
CHO
3
15%
80%
90%
65%
method A:
10%
15%
method B:
method C:
Scheme 7.
Experimental
(50 mL, 14%), at 25 °C for 30 min. The color of the solution
did not change. After this time, acetic acid (20 mL, 50%)
was added to the solution. The insoluble chlorinated reagent
was removed by filtration and washed with water (5 mL).
Procedure for the preparation of poly (N,N’-dichloro-N-
ethyl-benzene-1,3-disulfonamide) [PCBS] and N,N,N’,N’-
tetrachlorobenzene-1,3-disulfonamide [TCBDA]
Analytical data for N,N,N’,N’-tetrachlorobenzene-1,3-
disulfonamide
White solid, mp: 145-147 °C. IR (KBr) nmax/cm-1: 3050,
2950, 2900, 1570, 1462, 1417, 1377, 1304, 1167, 1082,
A sample of white finely powdered poly (N-ethyl-
benzene-1,3-disulfonamide) (1 g) or benzene-1,3-
disulfonamide (1 g) was dissolved in a solution of NaOCl

Vol. 21, No. 2, 2010
Ghorbani-Vaghei and Veisi
199
1
807, 776, 675. H NMR (250 MHz, CDCl3) d 7.95-8.09
(m, CH aromatic, 1H), 8.11-8.58 (m, CH aromatic, 2H),
8.79 (s, CH aromatic, 1H). m/e: 374 ([M+H]+), 339, 337,
321, 319, 305, 303, 272, 269, 267, 156, 154, 139, 125, 120,
104, 91, 77, 63. Anal. Calc. for C6H4N2S2O4Cl4: C, 19.25;
H, 1.06; N, 7.48; S, 17.11. Found: C, 19.05; H, 1.16; N,
6.94; S, 16.28.
Synthesis of tri(bis-indolyl)methanes in DMSO catalyzed
by TCBDA or PCBS
A mixture of indole (6.0 mmol), aldehyde, (d),
(1.0 mmol) and catalyst PCBS (0.05 g) or TCBDA
(0.05 mmol, 0.04 g) in DMSO (5 mL) was heated in an oil
bath until 100 °C. The reaction mixture was filtered after
10 min. The residue was washed with EtOH (5 mL). Then,
water (30 mL) was added to the filtrate, and the product
was precipated and filtered. The product was purified by
washing with cold EtOH (2 ×5 mL).
Analytical data for poly (N,N’-dichloro-N-ethyl-benzene-
1,3-disulfonamide)
White solid, mp: 175-178 °C, IR (KBr) nmax/cm-1: 3050,
2950, 2900, 1578, 1462, 1418, 1377, 1303, 1168, 1081,
Synthesis of tetra(bis-indolyl)methanes in DMSO catalyzed
by TCBDA or PCBS
1
809, 779, 674, 603, 570. H NMR (250 MHz, CDCl3) d
7.56-8.48 (b, CH aromatic).
A mixture of indole (8.0 mmol), aldehyde, (f or h),
(1.0 mmol), and catalyst PCBS (0.05 g) or TCBDA
(0.05 mmol, 0.04 g) in DMSO (5 mL) was heated in an oil
bath until 100 °C. The reaction mixture was filtered after
15 min. The residue was washed with EtOH (5 mL). Then,
water (30 ml) was added to the filtrate, and the product
was precipated and filtered. The product was purified by
washing with cold EtOH (2 ×5 mL).
Synthesis of bis(indolyl)methanes in ethanol catalyzed by
TCBDA or PCBS (method A)
A mixture of indole (2.0 mmol), aldehyde or ketone
(1.0 mmol) and catalyst [PCBS (0.05 g) or TCBDA
(0.05 mmol, 0.04 g)] in EtOH (3 mL) was stirred at room
temperature for the appropriate time (Table 1). The progress
of the reaction was monitored by TLC (4:1, n-hexan/
acetone). After completion of reaction, the organic solvent
was concentrated in vacuo and then CH2Cl2 (10 mL)
was added, and the catalyst was removed by filtration.
Evaporation of the solvent under reduced pressure
gave the products. Further purification was achieved by
recrystalization from ethanol-water to afford pure products.
Analytical data for compound e
o
Light red solid, mp 208-210 C. IR (KBr) nmax/cm-1:
3421, 2950, 2900, 1635, 1506, 1457, 1377, 1216, 1173,
1082, 742. 1H NMR (300 MHz, DMSO-d6) dH (ppm) 5.01
(s, CH2 benzylic, 6H), 5.72 (s, CH, 3H), 6.74-7.50 (m,
CH aromatic, 46H), 10.71 (s, NH, 6H). 13C NMR (300
MHz, DMSO-d6) dc (ppm) 40.08, 69.48, 111.85, 114.67,
115.24, 118.54, 118.82, 119.58, 121.25, 123.87, 127.05,
129.66, 137.03, 137.73, 138.15, 156.91. Anal. Calc. for
C78H60N6O3: C, 82.95; H, 5.35; N, 7.44. Found: C, 82.52;
H, 5.21; N, 7.36.
Synthesis of bis(indolyl)methanes in solid-state catalyzed
by TCBDA or PCBS (method B)
A mixture of indole (2.0 mmol), aldehyde or ketone
(1.0 mmol) and catalyst [PCBS (0.05 g) or TCBDA
(0.05 mmol, 0.04 g)] were added to a mortar and the
mixture was pulverized with a pestle. A spontaneouse
reaction took place (1-6 min, Table 1, montored byTlC, 4:1,
hexane/ acetone).After completion of the reaction, CH2Cl2
(10 mL) was added, and insoluble reagents were removed
by filtration. The filtrate was evaporated under reduced
pressure and the resulting crude material was purified by
recrystalization from ethanol-water to afford pure products.
Analytical data for compound g
Red solid, mp 250-251 °C d. IR (KBr) nmax/cm-1: 3417,
2926, 2854, 1609, 1506, 1456, 1413, 1338, 1218, 1172,
1127, 1012, 743.1H NMR (300 MHz, DMSO-d6) dH (ppm)
5.08 (s, CH2 benzylic, 8H), 5.76 (s, CH, 4H), 6.82-7.65
(m, CH aromatic, 60H), 10.70 (s, NH, 8H). 13C NMR (300
MHz, DMSO-d6) dc (ppm) 41.05, 70.40, 111.45, 114.52,
115.12, 117.85, 118.85, 119.26, 120.85, 122.82, 126.65,
129.26, 136.76, 137.43, 138.63, 157.43. Anal. Calc. for
C102H78N8O4: C, 82.79; H, 5.31; N, 7.57. Found: C, 82.12;
H, 5.20; N, 7.35.
Synthesis of bis(indolyl)methanes in H2O catalyzed by
TCBDA and TBAB (method C)
A mixture of indole (2.0 mmol), aldehyde or ketone
(1.0 mmol), TCBDA (0.05 mmol, 0.04 g) and CTAB
(5 mol%) in water (3 mL) was stirred at room temperature
for the appropriate time (Table 1). The progress of the
reaction was monitored by TLC. After completion of the
reaction, the solid which separated was filtered and then
recrystallized from ethanol-water to afford pure products.
Analytical data for compound I
°
Red solid, mp 255-257 C. IR (KBr) nmax/cm-1: 3420,
2912, 2860, 1612, 1510, 1435, 1403, 1327, 1218, 1170,
1118, 735. 1H NMR (300 MHz, DMSO-d6) dH (ppm) 5.10
(s, CH2 benzylic, 8H), 5.71 (s, CH, 4H), 6.75-7.85 (m, CH

200
Poly(N,N’-dichloro-N-ethyl-benzene-1, 3-disulfonamide) and N,N,N’,N’-Tetrachlorobenzene-1,3-disulfonamide
J. Braz. Chem. Soc.
aromatic, 60H), 10.65 (s, NH, 8H). 13C NMR (300 MHz,
DMSO-d6) dc (ppm) 42.10, 70.41, 111.43, 114.60, 115.10,
117.88, 118.86, 119.36, 120.01, 120.85, 122.09, 122.90,
126.65, 129.25, 136.82, 137.45, 138.70, 157.45. Anal.
Calc. for C102H78N8O4: C, 82.79; H, 5.31; N, 7.57. Found:
C, 82.35; H, 5.18; N, 7.42.
16. Ji, S.-J.; Zhou, M.-F.; Gu, D.-G.;Wang, S.-Y.; Loh, T.-P.; Synlett
2003, 2077.
17. Mo, L.-P.; Ma, Z.-C.; Zhang, Z.-H.; Synth. Commun. 2005, 35,
1997.
18. Mi, X.; Luo, S.; He, J.; Cheng, J.-P.; Tetrahedron Lett. 2004,
45, 4567.
19. Kamble, V. T.; Kadam, K. R.; Joshi, N. S.; Muley, D. B.; Catal.
Commun. 2007, 8, 498.
Supplementary Information
20. Pradhan, P. K.; Dey, S.; Giri,V. S.; Jaisankar, P.; Synthesis 2005,
1779.
1
Supplementary characterization data and H NMR
spectra are available, free of charge at http://jbcs.sbq.org.br,
as a PDF file
21. Xia, M.; Wang, S. H.; Yuan, W. B.; Synth. Commun. 2004, 34,
3175.
22. Ramesh, C.; Banerjee, J.; Pal, R.; Das, B.; Adv. Synth. Catal.
2003, 345, 557.
Acknowledgments
23. Reddy, B. M.; Sreekanth, P. M.; Lakshmanan, P.; J. Mol. Catal.
A: Chem. 2005, 237, 93.
We are thankful to Bu-Ali Sina University, Center of
Excellence of Chemical Methods (CEDCM) for financial
support, and the University of Sheffield for NMR, mass
spectra and CHN. Also the author acknowledges Prof. I.
Coldham from the University of Sheffield for this useful
comments and his kindness for hosting the author as a
research visitor.
24. Firouzabadi, H.; Iranpoor, N.; Jafarpour, M.; Ghaderi, A.;
J. Mol. Catal. A: Chem. 2006, 253, 249.
25. Pore, D. M.; Desai, U. V.; Thopate, T. S.; Wadgaonkar, P. P.;
ARKIVOC 2006, 12, 75; Zolfigol, M. A.; Salehi, P.; Shiri, M.;
Sayadi, A.; Abdoli, A.; Keypour, H.; Rezaeivala, M.; Niknam,
K.; Kolvari, E.; Mol. Divers. 2008, 12, 203.
26. Hosseini-Sarvari, M.; Acta Chim. Slovenica 2007, 54,
354.
References
27. Dabiri, M.; Salehi, P.; Baghbanzadeh, M.;Vakilzadeh,Y.; Kiani,
S.; Monatshefte for Chemie 2007, 138, 595.
28. Hagiwara, H.; Sekifuji, M.; Hoshi, T.; Qiao, K.;Yokoyama, C.;
Synlett 2007,1320.
1. Sundberg, R. J.; The Chemistry of Indoles, Academic Press:
New York, USA, 1996.
2. Zeligs, M. A.; J. Med. Food 1998, 1, 67-68.
3. Chakrabarty, M.; Ghosh, N.; Basak, R.; Harigaya, Y.;
Tetrahedron Lett. 2002, 43, 4075.
29. Kamble, V. T.; Bandgar, B. P.; Bavikar, S. N.; Chin. J. Chem.
2007, 25, 13.
4. Bandgar, B. P.; Shaikh, K.A.; Tetrahedron Lett. 2003, 44, 1959.
5. Reddy, A. V.; Ravinder, K.; Reddy, V. L. N.; Venkateshwer
Goud, T.; Ravikanth, V.; Venkateswarlu, Y.; Synth. Commun.
2003, 33, 3687.
30. Niknam, K.; Zolfigol, M. A.; Sadabadi, T.; Nejati, A.; J. Iran.
Chem. Soc. 2006, 3, 318.
31. Lin, X. F.; Cui, S. L.; Wang, Y. G.; Synth. Commun. 2006, 36,
3153.
6. Remers, W. A. In Heterocyclic Compounds; Houlihan, W. J.,
ed.; Interscience Publishers: New York, USA, 1972, p. 1.
7. Maiti, A. K.; Bhattacharyya, P.; J. Chem. Res. 1997, 424.
8. Sharma, G. V. M.; Reddy, J. J.; Lakshmi, P. S.; Krishna, P. R.;
Tetrahedron Lett. 2004, 45, 7729.
32. Zeng, X. F.; Ji, S. J.; Lett. Org. Chem. 2006, 3, 374.
33. Zhang, L. P.; Li, Y. Q.; Zhou, M. Y.; Chin. Chem. Lett. 2006,
17, 723.
34. Koshima, H.; Matsuaka, W.; J. Heterocycl. Chem. 2002,
1089.
9. Firouzabadi, H.; Iranpoor, N.; Jafari, A. A. ; J. Mol. Catal. A:
Chem. 2005, 244, 168.
35. Khalafi-Nezhad, A.; Parhami, A.; Zare, A.; Moosavi Zare, A.
R.; Hasaninejad, A.; Panahi, F.; Synthesis 2008, 617.
36. Azizi, N.; Torkian, L.; Saidi, M. R.; J. Mol. Catal. A: Chem.
2007, 275, 109.
10. Deb, M. L.; Bhuyan, P. J.; Tetrahedron Lett. 2006, 47, 1441.
11. Zhang, Z.-H.; Yin, L.; Wang, Y.-M.; Synthesis 2005, 1949.
12. Li, J.-T.; Dai, H.-G.; Xu,W.-Z.; Li, T.-S.; Ultrasonics Sonochem.
2006, 13, 24.
37. Mehrazma, S.; Azizi, N.; Saidi, M. R.; Lett. Org. Chem. 2006,
3, 161.
13. Bandgar, B. P.; Shaikh, K. A.; Tetrahedron Lett. 2003, 44,
1959.
38. Zolfigol, M.A.; Salehi, P.; Shiri, M.; Tanbakouchian, Z.; Catal.
Commun. 2007, 8, 173.
14. Karthik, M.; Tripathi, A. K.; Gupta, N. M.; Palanichamy, M.;
Murugesan, V.; Catal. Commun. 2004, 5, 371.
39. Khodaei, M. M.; Mohammadpoor-Baltork, I.; Memarian, H. R.;
Khosropour, A. R.; Nikofar, K.; Ghanbary, P.; J. Heterocyclic
Chem. 2008, 45, 1.
15. Penieres-Carrillo, G.; García-Estrada, J. G.; Gutiérrez-Ramírez,
J. L.; Alvarez-Toledano, C.; Green Chem. 2003, 5, 337.
40. Ghorbani-Vaghei, R.; Jalili, H.; Synthesis 2005, 1099.

Vol. 21, No. 2, 2010
Ghorbani-Vaghei and Veisi
201
41. Ghorbani-Vaghei, R.; Zolfigol, M, A.; Chegeny, M.; Veisi, H.;
Tetrahedron Lett. 2006, 47, 4505.
43. Ghorbani-Vaghei, R.; Shahbazee, E.; Veisi, H.; Mendeleev
Commun. 2005, 207.
42. Zolfigol, M, A.; Ghorbani-Vaghei, R.; Mallakpour, S;
Chehardoli, G.; Ghorbani Choghamani, A.; Yazdi Hosain, A.;
Synthesis 2006, 1631.
44. Chakrabarty, M.; Sarkar, S.; Tetrahedron Lett. 2002, 43, 1351.
45. Wang, S.-Y.; Ji, S.-J.; Tetrahedron 2006, 62, 1527.
Received: March 2, 2009
Web Release Date: November 6, 2009

J. Braz. Chem. Soc., Vol. 21, No. 2, S1-S10, 2010.
Printed in Brazil - ©2010 Sociedade Brasileira de Química
0103 - 5053 $6.00+0.00
Poly (N,N’-dichloro-N-ethyl-benzene-1, 3-disulfonamide) and N,N,N’,N’-
Tetrachlorobenzene-1,3-disulfonamide as Novel Catalytic Reagents for Synthesis
of Bis-indolyl, Tris-indolyl, Di(bis-indolyl), Tri(bis-indolyl) and Tetra(bis-indolyl)
methanes under Solid-State, Solvent and Water Conditions
Ramin Ghorbani-Vaghei*,a and Hojat Veisia,b
aDepartment of Organic Chemistry, Faculty of Chemistry, Bu-Ali Sina University, 65174, Hamadan, Iran
bDepartment of Chemistry, Payame Noor University, Songhor, Kermanshah, Iran
3,3’-Bisindolyl-phenylmethane (Table 1, entry 1)
3,3’-Bisindolyl-4-bromophenylmethane (Table 1, entry 5)
Pink solid, mp 110-112 °C. IR (KBr) nmax/cm-1: 3410,
3054, 1487, 1455, 1089. 1H NMR (90 MHz, CDCl3) dH
(ppm) 6.66 (s, 2H), 7.02-7.45 (m, ArH, 12H), 7.85 (br s,
NH, 2H). MS: (MS-EI) m/z 361.
Solid, mp 124-125 °C. IR (KBr) nmax/cm-1: 3402, 3050,
2986, 1615, 1600, 1455, 1112.1H NMR (90 MHz, CDCl3) dH
(ppm) 5.88 (s, 1H), 6.68 (s, 2H), 7.13-7.45 (m, ArH, 13H),
7.95 (br s, NH, 2H). 13C NMR (75 MHz, CDCl3) dc (ppm)
31.6, 110.9, 111.9, 118.4, 119.5, 1121.2, 124.0, 126.3, 127.1,
128.5, 128.6, 137.0, 145.2. MS: (MS-EI) m/z 322.
3,3’-Bisindolyl-4-chlorophenylmethane (Table 1, entry 6)
mp 75-76 oC, FT-IR (KBr) nmax/cm-1: 3409, 2958, 1456,
1488. 1H NMR (300 MHz, acetone-d6) d (ppm) 5.90 (s, 1H),
3,3’-Bisindolyl-4-methylphenylmethane (Table 1, entry 2)
Solid, mp 97-98 °C. IR (KBr) nmax/cm-1: 3452, 3112,
3045, 2950, 1604, 1523, 1210, 1052, 765. 1H NMR (90
MHz, CDCl3) dH (ppm) 2.38 (s, 3H), 5.85 (s, 1H), 6.70-
7.55 (m,ArH, 14H), 7.85 (br s, NH, 2H).MS: (MS-EI) m/z
336. Anal. Calc. for C24H20N2: C, 85.68; H, 5.99; N, 8.33.
Found: C, 85.45; H, 5.88; N, 8.14.
13
6.82 (s, 2H), 6.89-7.39 (m, 12H), 9.99 (s, 2H, N-H). C
NMR (75 MHz, acetone-d6) d (ppm) 40.8, 112.1, 119.2,
120.1, 120.3, 121.9, 124.5, 128.1, 129.2, 138.0, 143.4.
3,3’-Bisindolyl-2-chlorophenylmethane (Table 1, entry 7)
1H NMR (90 MHz, CDCl3) d (ppm) 7.89 (br s, 2H), 7.07-
7.51 (m, 12H), 6.53 (s, 2H), 6.36 (s, 1H); 13C NMR (75 MHz,
CDCl3) d (ppm) 36.9, 110.1, 111.3, 119.3, 119.8, 122.0,
124.0, 126.7, 127.0, 128.3, 30.4, 130.7, 135.3, 136.7, 141.5.
3,3’-Bisindolyl-2-methoxylphenylmethane (Table 1, entry 3)
Red solid, mp 134-136 °C. IR (KBr) nmax/cm-1: 3408,
3056, 2932, 1597, 1486, 1450, 1335, 1102, 745. 1H NMR
(90 MHz, CDCl3) dH (ppm) 3.82 (s, 3H), 6.32 (s, 1H),
6.61 (s, 2H), 6.81-7.40 (m, ArH, 12H), 7.80 (br s, NH,
2H). 13C NMR (75 MHz, CDCl3) dc (ppm) 32.3, 56.0,
110.0, 110.8, 111.1, 119.2, 119.8, 120.2, 120.6, 121.9,
123.7, 127.2, 129.9, 132.5, 136.9, 157.1. Anal. Calc. for
C24H20N2O: C, 81.79; H, 5.72; N, 7.95. Found: C, 81.24;
H, 5.45; N, 7.86.
3,3’-Bisindolyl-2-furylmethane (Table 1, entry 8)
1H NMR (90 MHz, CDCl3) d (ppm) 7.74 (br s, 2H), 7.32-
7.63 (m, 9H), 7.09 (s, 2H), 6.21-6.35 (m, 2H), 5.82 (s, 1H);
13CNMR(75MHz,CDCl3)d(ppm)41.2,102.1,110.3,111.8,
112.6, 119.4, 120.3, 121.5, 122.6, 131.0, 136.4, 141.2, 152.0.
3,3’-Bisindolyl-4-hydroxyphenylmethane (Table 1, entry 9)
o
mp 212-213 C, FT-IR (KBr) nmax/cm-1: 3420, 3239,
3,3’-Bisindolyl-4-methoxyphenylmethane (Table 1, entry 4)
1H NMR (90 MHz, CDCl3) dH (ppm) 3.84 (s, 3H), 5.90
(s, 1H), 6.64-7.65 (m, ArH, 14H), 7.80 (br s, NH, 2H).
13C NMR (75 MHz, CDCl3) d (ppm) 39.7, 55.6, 111.5,
114.0, 119.6, 120.4, 120.4, 122.3, 123.9, 127.5,130.0,
136.7, 137.1, 158.3.
1455, 1511, 1616. 1H NMR (90 MHz, DMSO) d (ppm) 7.58
(br s, 2H), 6.69-7.24 (m, 13H), 6.67 (s, 2H), 5.85 (s, 1H).
13C NMR (300 MHz, DMSO-d6) d (ppm) 31.12, 111.89,
115.28, 118.58, 119.19, 119.71, 121.30, 123.89, 127.17,
129.66, 135.71, 136.93, 137.10, 155.79.
3,3’-Bisindolyl-4-nitrophenylmethane (Table 1, entry 10)
1H NMR (90 MHz, CDCl3) d (ppm) 8.19 (d, 2H, J 7.81),
7.76 (br s, 2H), 7.40-7.58 (m, 10H), 7.03 (s, 2H), 6.05 (s,
*e-mail: rgvaghei@yahoo.com

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Poly (N,N’-dichloro-N-ethyl-benzene-1, 3-disulfonamide)
J. Braz. Chem. Soc.
1H); 13C NMR (75 MHz, CDCl3) d (ppm) 44.5, 110.0,
112.1, 119.6, 119.8, 120.9, 121.3, 121.9, 130.2, 133.8,
136.2, 143.1, 145.2
758, 699 cm-1. 1H NMR (90 MHz, CDCl3) dH (ppm) 1.56
(m, 6H), 2.48 (m, 4H), 6.81 (s, 2H), 7.03-7.65 (m, 8H),
7.84 (br s, NH, 2H).
3,3’-Bisindolyl-3-nitrophenylmethane (Table 1, entry 11)
1H NMR (90 MHz, CDCl3) d (ppm) 8.46 (br s, 2H),
7.02-7.87 (m, 12H), 6.61 (s, 2H), 5.34 (s, 1H); 13C NMR
(75 MHz, CDCl3) d (ppm) 34.9, 111.5, 111.6, 119.5, 120.7,
121.9, 122.2, 124.3, 126.8, 129.6, 131.2, 132.6, 134.2,
136.8, 149.7.
Analitical data for compound Tri-indolylmethane
o
1
Yellow solid, mp 243-245 C. H NMR (90 MHz,
DMSO-d6) dH (ppm) 9.67 (br s, 2H), 6.24 (s, 3H), 6.27-6.87
(m, 12H), 5.47 (s, 1H). IR (KBr) nmax/cm-1: 3403, 3043,
2918 cm-1. MS: (MS-EI) m/z 361.
Analitical data for compound (a)
o
1
3,3’-Bisindolyl-4-(N,N-dimethyl)phenylmethane (Table 1,
entry 12)
1H NMR (90 MHz, CDCl3) dH (ppm) 3.28 (s, 6H), 5.75
(s, 1H), 6.76-7.84 (m,ArH, 14H), 7.82 (br s, NH, 2H).MS:
(MS-EI) m/z 365.
Yellow solid, mp 243-245 C. H NMR (90 MHz,
DMSO-d6) dH (ppm) 9.98 (br s, 2H), 9.81 (br s, 1H),
6.45 (m, 2H), 6.52-6.93 (m, 12H). 13C NMR (90 MHz,
DMSO-d6) dc (ppm) 200.8, 160.5, 137.4, 136.8, 125.5,
124.4, 123.9, 121.0, 120.5, 118.3, 117.7, 117.0, 113.9,
111.7, 111.5. MS: (MS-EI) m/z 364.
3,3’-Bisindolyl-1-(2-phenylethylene)methane (Table 1,
entry 13)
Analitical data for compound (c)
1H NMR (90 MHz, CDCl3) d (ppm) 5.92-6.07 (m, 2H),
5.76 (m, 1H), 6.71 (s, 2H), 6.89-7.68 (m, 15H), 8.02 (br s,
2H, NH). MS: (MS-EI) m/z 348.
Pink solid, mp 194-195 oC. FT-IR (KBr) nmax/cm-1: 3405,
3049, 1622, 1455, 1216 cm-1. 1H NMR (90 MHz, DMSO-d6)
dH (ppm) 5.75 (s, CH, 1H), 6.29 (s, 4H), 7.05-7.40 (m, CH
aromatic, 20H), 7.31 (br s, NH, 4H). 13C NMR (90 MHz,
DMSO-d6)dc (ppm)142.5, 136.7, 128.1, 126.8, 123.6, 120.9,
119.2, 118.4, 118.3, 111.5, 29.1. MS: (MS-EI) m/z 566.200.
3,3’-Bisindolyl-[2]thienylmethane (Table 1, entry 14)
Brown solid, mp 185-186 °C. IR (KBr) nmax/cm-1: 3412,
1715, 1452, 1260, 1105 cm-1. 1H NMR (90 MHz, CDCl3)
dH (ppm) 6.18 (s, 1H), 6.87 (s, 2H), 6.92-7.48 (m, ArH,
11H), 7.98 (br s, NH, 2H). Anal. Calc. for C21H16N2S: C,
76.80; H, 4.91; N, 8.53. Found: C, 76.52; H, 5.10; N, 8.35.
Analitical data for compound (Table2, entry 1)
1H NMR (90 MHz, DMSO-d6) dH (ppm) 10.68 (br s,
2H), 8.53 (br s, 2H), 6.75-7.55 (m, 12H), 6.35 (s, 1H), 4.12
(s, 3H), 2.55 (t, 2H), 2.23 (t, 2H), 1.78 (m, 2H)..Anal. Calc.
for C32H32N2O5: C, 73.26; H, 6.15; N, 5.34. Found: C, 72.86;
H, 6.18; N, 5.23. MS: (MS-EI) m/z 524.
3,3’-Bisindolyl-1-butylmethane (Table 1, entry 15)
1H NMR (90 MHz, CDCl3) d (ppm) 0.80 (t, J 6.7 Hz,
3H), 1.25-1.29 (m, 6H), 4.62 (t, J 6.7 Hz, 1H), 6.80 (d, J
2.5 Hz, 2H), 6.89-7.68 (m, 8H), 8.12 (br s, 2H, NH). MS:
(MS-EI) m/z 302.
Analitical data for compound (Table2, entry 2)
1H NMR (90 MHz, DMSO-d6) dH (ppm) 10.59 (br s,
2H), 8.86 (br s, 2H), 6.92-7.62 (m, 12H), 6.22 (s, 1H), 5.22
(s, 4H), 2.30 (s, 3H). Anal. Calc. for C28H24N2O4: C, 74.32;
H, 5.35; N, 6.19. Found: C, 73.92; H, 5.12; N, 5.79. MS:
(MS-EI) m/z 452.
3,3’-Bisindolyl-1-methyl-1-phenylmethane (Table 1, entry
16)
o
1
mp 165-167 C. H NMR (90 MHz, CDCl3) d (ppm)
2.40 (s, 3H), 6.67 (s, 2H), 6.95-7.43 (m, 13H), 7.91 (br s,
2H, NH). MS: m/z 336.
2,2’-Bisindolyl-phenylmethane (Table2, entry 3)
1H NMR (90 MHz, DMSO-d6) dH (ppm) 7.94 (br s, 2H),
7.22-7.66 (m, 13H), 6.04 (s, 1H), 2.23 (s, 6H). Anal. Calc.
for C25H22N2: C, 85.68; H, 6.33; N, 7.99. Found: C, 85.43;
H, 5.95; N, 7.68. MS: (MS-EI) m/z 350.
3,3’-Bisindolyl-1-methyl-1-(4-nitro)phenylmethane (Table
1, entry 17)
1H NMR (90 MHz, CDCl3) d (ppm) 2.46 (s, 3H), 6.78
(s, 2H), 6.79-7.68 (m, 12H), 7.98 (br s, 2H, NH). MS:
(MS-EI) m/z 381.
2,2’-Bisindolyl-4-methoxyphenylmethane (Table2, entry 4)
1H NMR (90 MHz, DMSO-d6) dH (ppm) 7.90 (br s,
2H), 7.06-7.66 (m, 12H), 6.12 (s, 1H), 3.73 (s, 3H), 2.30 (s,
6H).Anal. Calc. for C26H24N2O: C, 82.07; H, 6.36; N, 7.36.
Found: C, 81.67; H, 6.14; N, 7.03. MS: (MS-EI) m/z 380.
3,3’-Bisindolyl-[1,1]cyclohexane (Table 1, entry 18)
°
Red solid, mp 115-116 C. IR (KBr) nmax/cm-1: 3478,
3020, 2935, 1603, 1522, 1421, 1335, 1216, 1099, 1017,

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Ghorbani-Vaghei and Veisi
S3
Figure S1. 1H NMR (CDCl3) spectrum of 3,3’-bisindolyl-phenylmethane (Table 1, entry 1).
Figure S2. 1H NMR (CDCl3) spectrum of 3,3’-bisindolyl-4-chlorophenylmethane (Table 1, entry 6).

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Poly (N,N’-dichloro-N-ethyl-benzene-1, 3-disulfonamide)
J. Braz. Chem. Soc.
Figure S3. 1H NMR (CDCl3) spectrum of 3,3’-bisindolyl-4-(N,N-dimethyl)phenylmethane (Table 1, entry 12).
Figure S4. 1H NMR (CDCl3) spectrum of compound (a).

Vol. 21, No. 2, 2010
Ghorbani-Vaghei and Veisi
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Figure S4. 1H NMR (CDCl3) spectrum of compound (a). Same compound? Different spectrum?Again S4 ?
Figure S5. 1H NMR (DMSO-d6) spectrum of compound (c).

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Poly (N,N’-dichloro-N-ethyl-benzene-1, 3-disulfonamide)
J. Braz. Chem. Soc.
Figure S6. 1H NMR (DMSO-d6) spectrum of compound tri-indolylmethane.
Figure S7. 1H NMR (DMSO-d6) spectrum of compound (e).

Vol. 21, No. 2, 2010
Ghorbani-Vaghei and Veisi
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Figure S8. 1H NMR (DMSO-d6 + D2O) spectrum of compound (e).

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Poly (N,N’-dichloro-N-ethyl-benzene-1, 3-disulfonamide)
J. Braz. Chem. Soc.
Figure S9. 1H NMR and 13C NMR (DMSO-d6) spectrum of compound (e).

Vol. 21, No. 2, 2010
Ghorbani-Vaghei and Veisi
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Figure S10. 1H NMR (DMSO-d6) spectrum of compound (g).
Figure S11. 1H NMR (CDCl3) spectrum of compound 3,3’-bisindolyl-4-hydroxyphenylmethane (Table 1, entry 9).

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Poly (N,N’-dichloro-N-ethyl-benzene-1, 3-disulfonamide)
J. Braz. Chem. Soc.
Figure S12. 1H NMR (CDCl3) spectrum of compound 2,2’-bisindolyl-phenylmethane (Table2, entry 3).
Figure S13. 1H NMR (CDCl3) spectrum of compound 3,3’-bisindolyl-4-bromophenylmethane (Table 1, entry 5).