Solvent free, phosphine free Pd-catalyzed annulations of aryl bromides with diarylacetylenes

Article abstract of DOI:10.1039/c3ra41924j

Palladium nanoparticles and sodium acetate catalyze the reaction of aryl bromide with diarylacetylene to produce annulated products in good yield. One equivalent of PEG-600 serves as the solvent. This procedure is compatible with a wide variety of functional groups.

Full text of DOI:10.1039/c3ra41924j

RSC Advances
View Article Online
View Journal
PAPER
Solvent free, phosphine free Pd-catalyzed annulations
of aryl bromides with diarylacetylenes3
Cite this: DOI: 10.1039/c3ra41924j
Ansuman Bej, Amarnath Chakraborty and Amitabha Sarkar*
Received 19th April 2013,
Accepted 3rd July 2013
Palladium nanoparticles and sodium acetate catalyze the reaction of aryl bromide with diarylacetylene to
produce annulated products in good yield. One equivalent of PEG-600 serves as the solvent. This
procedure is compatible with a wide variety of functional groups.
DOI: 10.1039/c3ra41924j
www.rsc.org/advances
The Pd-nanoparticles were prepared by heating K2PdCl4
and PEG-600 at 70 uC for 15 mins. The colloidal solution was
Introduction
Polycyclic aromatic hydrocarbons (PAHs) have been the
subject of popular research due to their high stability,
enhanced ability to transport charges, fluorescent properties
in the solid state, and their applications in organic optoelec-
tronic devices and organic semiconductor luminescent mate-
rials.1 The recent discovery of graphene, which can be
regarded as giant PAHs, has further stimulated interest in
this area.2
Several approaches have been reported in the literature for
efficient assemblage of fused aromatic rings.3 Among these,
metal mediated annulation reactions have received particular
attention in recent time.4 Palladium mediated annulation5 of
aryl halide with alkynes, emerged as a useful route for the
synthesis of a wide variety of polycyclic aromatics. An
intriguing yet fascinating aspect of these palladium mediated
reactions is the change in product selectivity as a function of
reaction parameters6 as depicted in Scheme 1.
cooled to room temperature and it was found to be stable for
several days. In a preliminary experiment, 2-bromobenzoni-
trile, diphenylacetylene and potassium carbonate were added
to a dispersion of freshly prepared palladium nanoparticles
(average size y3.8 nm, see ESI ) and the mixture was stirred at
3
80 uC. 5,6,7,8-Tetraphenylnaphthalene-2-carbonitrile was
formed as the major product along with some biaryls typically
in 3–5 h (Table 1). No other product6 was formed if the
equivalents of arylbromide and alkyne were altered (Table 1,
entries 13 and 14). It was eventually found that heating the
substrates (aryl bromide and alkyne) at 80 uC with palladium
nanoparticles and sodium acetate afforded excellent yield of
desired annulated product in 2.5 h (entry 8, Table 1).
This reaction condition is compatible with a variety of
functional groups such as keto, ester, cyano, nitro and
carboxylic acid. Reactions with electron-deficient aryl bro-
In this report we describe the first example of nano-sized
palladium catalyzed annulation reaction of aryl bromides with
alkynes leading to 1,2,3,4-tetrasubstituted naphthalene deri-
vatives.
There are several advantages of this reaction: it is free of
phosphine, highly regio-selective, operationally simple, and
produces good to excellent yield of product with high catalytic
efficiency. No solvent other than PEG was necessary. An
equivalent amount of PEG-600 (needed to prepare Pd-
nanoparticles7) with respect to the aryl bromides was found
to be adequate. Accordingly, this protocol appears to be highly
competitive, if not superior to many of the methods reported
earlier.4e,5b,q
Department of Organic Chemistry, Indian Association for the Cultivation of Science,
Kolkata 700 032, India. E-mail: ocas@iacs.res.in; Fax: +91-33-2473 2805;
Tel: +91-33-2473 4971
Electronic supplementary information (ESI) available: 1H and 13C NMR spectra
3
of annulated products 3a–3y, and X-ray crystal data of compound 3b and 3i.
CCDC 928656 and 928657. For ESI and crystallographic data in CIF or other
electronic format see DOI: 10.1039/c3ra41924j
Scheme 1
This journal is ß The Royal Society of Chemistry 2013
RSC Adv.

View Article Online
Paper
RSC Advances
Table 1 Screening of conditions for annulation reactions
Entry
Ar–Br (eq)
Alkyne (eq)
K2PdCl4 (mol%)
Base
T (uC)
Time (h)
Yield (%)
1
2
3
4
5
6
1
1
1
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
2
2
2
1
1
3
5
5
5
3
3
3
5
5
5
3
5
5
5
K2CO3
K2CO3
K2CO3
K2CO3
NaOAc
NaOAc
NaOAc
NaOAc
NaOAc
KOAc
NaOH
NaOH
NaOAc
K2CO3
80
80
80
100
r.t.
60
80
80
80
80
60
100
80
80
3
3
5
5
5
5
5
2.5
5
5
5
5
3
30
50
57
55
0
45
57
82
82
70
0
7
8a
9
10
11
12
13
14
0
40
35
3
a
Typical conditions subsequently used for most of the reactions studied.
mides afford product with better yield (Table 2) than those
with electron-rich aryl bromides or bromoheterocycles
(Table 3). There was no significant change in the yield of the
annulation product as a result of positioning of substituents
(ortho, meta and para).
in 2.5–4 h at 80 uC in absence of any phosphine ligand.
Moreover, the present protocol uses aryl bromides rather than
aryl iodides. Nitro substituted aryl bromides (Table 2, entries 5
and 6) yielded desired products in 80–83%, at variance with an
earlier observation.9
It has been observed that the ortho and para substituted
aryl bromides reacted with diphenylacetylene to provide only
one product. In case of meta substituted aryl bromides
(Table 2, entries 3, 4, 6, 9, 15, 17, and Table 3, entry 2) a
small amount of the isomeric product (5–10%) was also
formed. Again, the heteroaryl bromides or iodide (Table 3,
A possible mechanistic pathway is depicted in Scheme 2.
After the first insertion of the acetylene, the intermediate can
undergo a second insertion followed by ortho-metalation and
finally reductive elimination (path A).4c,5b,k Alternatively, ortho-
palladation might precede insertion of the second alkyne
molecule (path B).5b,k In both pathways, intermediacy of PdIV
has been invoked in keeping with current observations.12
If PdIV is not an intermediate, we could envisage an
alternative pathway where the PdII is involved in an insertion
reaction leading to C–C bond formation, followed by a
b-hydride elimination to afford the desired product as shown
in Scheme 3.
entries 6,
7 and 9) furnished only one regioisomer.
3-Iodopyridine, on the other hand, produced about 5% of
the regioisomeric product (Table 3, entry 7).
It may be pertinent, at this point, to compare some of these
results with related reactions reported earlier using homo-
geneous palladium catalysis. It was reported earlier8 that a
similar reaction between methyl 2-iodobenzoate and dipheny-
lacetylene yielded isocoumarin as the only identified product
in moderate yield after a prolonged reaction. Under the
present reaction condition, methyl 2-bromobenzoate and
diphenylacetylene afforded tetrasubstituted naphthalene only
(Table 2, entry 7). Use of a mild base like NaOAc and absence
of a strong electrolyte like LiCl appears to have suppressed
participation of the carbomethoxy group in the present case
and consequently no isocoumerin was produced in the present
study.
Conclusions
In conclusion, a new, highly regioselective, phosphine-free
protocol was developed for efficient synthesis of densely
substituted naphthalene derivatives. It is an operationally
simple and mild method that uses essentially solvent-free (a
small amount of PEG is used as a ‘green’ reagent13 and
stabilizer of nanoparticles) and ligand-less condition in tune
with the current thrust on ‘‘green’’ technology.
Another report described the reaction between aryl iodide
and diphenylacetylene (2 equiv.) at 100 uC for 24 h in presence
of PPh3 or P(o-tol)3 and Et3N to produce naphthalene
derivatives in moderate yield.5q In the Pd-nanoparticle
catalyzed reaction described herein, the reaction is complete
RSC Adv.
This journal is ß The Royal Society of Chemistry 2013

View Article Online
RSC Advances
Paper
Table 2 Pd-catalyzed annulation of aryl bromidesa
Time
(h)
Yield
(%)b
Time
(h)
Yield
(%)b
Entry Ar-Br
1
Product
Entry Ar-Br
11
Product
2.5
82
85
80
75
83
80
76
3
3
3
3
3
3
3
84
76
73
61
72
75
62
2
3
4
5
6c
7
2.5
2.5
3
12
13
14
15c
16
17c
3
3
3
8
3
70
18
3
73
This journal is ß The Royal Society of Chemistry 2013
RSC Adv.

View Article Online
Paper
RSC Advances
Table 2 (Continued)
Time
(h)
Yield
(%)b
Time
(h)
Yield
(%)b
Entry Ar-Br
9
Product
Entry Ar-Br
19
Product
3
73
4
59
10
3
65
20
4
59
a
Reaction condition: aryl bromide (1 mmol), diphenylacetylene (2 mmol), K2PdCl4 (5 mol%), NaOAc (2 mmol), PEG-600 (1.16 mmol), 80 uC
b
c
under Argon. Yield of the isolated product. Isomeric products were obtained in 7%, 4% and 5% for entries 6, 15 and 17 respectively.
125.84, 125.8, 124.8, 117.8, 110.4; IR (KBr): 3391, 3080, 3053,
Experimental section
3026, 2218, 1599, 1493, 1443, 1383, 1338, 1072, 1028 cm21
HRMS calcd for C35H24N [M + H]+: 458.1909 found 458.1902.
;
General comments
5,6,7,8-Tetraphenylnaphthalene-2-carbonitrile (3b). mp 230–
232 uC; H NMR (500 MHz, CDCl3): d: 8.04 (s, 1H), 7.73 (d, J =
All chemicals were purchased from commercial suppliers
(Aldrich, Merck, Avra and SRL) and used as received. All 1H,
13C NMR spectra were recorded on a Bruker-Avance DPX300
and Bruker-Avance III DPX500 for a CDCl3 solution and
reported in ppm (d). Electrospray ionisation mass spectroscopy
(ESI-MS) experiments were carried out on Microtek QtoF Micro
YA 263 spectrometer in positive ion ESI mode.
1
8.5 Hz, 1H), 7.50 (d, J = 8.25 Hz, 1H), 7.30–7.17 (m, 10H), 6.90–
6.82 (m, 10H); 13C NMR (125 MHz, CDCl3): d: 142.3, 140.9,
139.8, 139.7, 139.3, 138.9, 138.6, 138.2, 133.6, 133.5, 131.5,
131.2, 131.17, 131.13, 131.0, 128.5, 128.1, 127.9, 127.3, 127.1,
126.9, 126.7, 126.3, 125.9, 119.7, 109.4; IR (KBr): 3435, 3418,
3078, 3057, 3022, 1950, 1897, 1880, 1603, 1497, 1439, 1367,
1068, 1030 cm21; HRMS calcd for C35H23NNa [M + Na]+:
480.1728 found 480.1728.
General procedure for the Pd catalyzed annulation reaction
Weighted amount of K2PdCl4 (16 mg, 5 mol%) and PEG 600
(700 mg, 1.16 mmol) was heated at 70 uC for 15 min to form
colloidal Pd. Then it was cooled to room temperature, aryl
bromide (1 mmol) and diphenylacetylene (2 mmol) and NaOAc
(182 mg, 2 eq) were added then stirred at 80 uC for the
specified time. Then the reaction mixture was allowed to cool
at room temperature, extracted with dichloromethane and the
organic layers were dried over anhydrous Na2SO4 and
concentrated in vacuum. The residue thus obtained was
purified by flash column chromatography on silica gel
(230y400 mesh) with a mixture of ethyl acetate (2–10%) and
petroleum ether as eluent.
5,6,7,8-Tetraphenylnaphthalene-1-carbonitrile (3a). mp .
240 uC; 1H NMR (500 MHz, CDCl3): d: 7.93–7.89 (m, 2H),
7.40 (dd, J = 7.0, 8.25 Hz, 1H), 7.31–7.17 (m, 10H), 6.87–6.79
(m, 10H); 13C NMR (125 MHz, CDCl3): d: 142.4, 140.6, 139.8,
139.7, 139.5, 138.8, 138.6, 137.4, 137.2, 132.8, 132.7, 132.3,
131.3, 131.0, 130.8, 128.2, 127.9, 127.7, 127.1 126.8, 126.7,
5,6,7,8-Tetraphenylnaphthalene-2-carboxylic acid (3c). mp
235–238 uC; 1H NMR (500 MHz, CDCl3): d: 8.42 (s, 1H), 7.91 (d,
J = 8.5 Hz, 1H), 7.63 (d, J = 8.5 Hz, 1H), 7.20–7.12 (m, 10H),
6.80–6.75 (m, 10H); 13C NMR (125 MHz, CDCl3): d: 171.9,
141.8, 140.2, 140.1, 139.1, 138.7, 138.6, 134.8, 131.5, 131.3,
131.2, 131.1, 127.8, 127.6, 127.0, 126.8, 126.5, 125.8, 125.7,
125.4; IR (KBr): 3055, 3012, 2654, 2536, 1689, 1599, 1564, 1493,
1441, 1367, 1306, 1279, 1072, 1026 cm21; HRMS calcd for
C
35H24O2Na [M + Na]+: 499.1674 found 499.1675.
1
6-Nitro-1,2,3,4-tetraphenylnaphthalene (3d)14. H NMR (500
MHz, CDCl3): d: 8.60 (s, 1H), 8.11 (dd, J = 2.5, 9.25 Hz,1H), 7.76
(d, J = 9.5 Hz, 1H), 7.29–7.18 (m, 10H), 6.89–6.81 (m, 10H); 13
C
NMR (125 MHz, CDCl3): d: 145.7, 142.9, 141.3, 140.8, 139.8,
139.7, 138.9, 138.6, 138.1, 134.8, 131.3, 131.2, 131.1, 130.9,
129.0, 128.1, 128.0, 127.4, 127.2, 126.9, 126.0, 125.9, 123.9,
119.2; HRMS calcd for C34H24NO2 [M + H]+: 478.1807 found
478.1802.
RSC Adv.
This journal is ß The Royal Society of Chemistry 2013

View Article Online
RSC Advances
Paper
Table 3 Pd-catalyzed annulation of aryl bromidesa
Time
(h)
Yield
(%)b
Time
(h)
Yield
(%)b
Entry
1
Ar-Br
Product
Entry
5
Ar-Br
Product
4
51d
53d
46d
49d
3
4
4
4
62
52
60
49
2c
3
4
4
6
3
7c
4
8
a
Reaction conditions: aryl bromide (1 mmol), diphenylacetylene (2 mmol), K2PdCl4 (5 mol%), NaOAc (2 mmol), PEG-600 (1.16 mmol), 80 uC
b
c
d
under Argon. Yield of the isolated product. Isomeric products were obtained in 5% and 10% for entries 2 and 7 respectively. Homo-
coupling products were isolated in 5%,7%,7% and 10% from corresponding aryl bromides in entries 1,2,3,4 respectively and identified after
comparison with literature7b,10,11 data.
140.26, 140.24, 140.0, 139.9, 139.2, 138.9, 138.6, 134.3, 131.5,
131.4, 131.3, 131.2, 130.1, 128.5, 127.8, 127.5, 126.9, 126.8,
125.7, 125.6, 125.3, 52.3.
Methyl 5,6,7,8-tetraphenylnaphthalene-1-carboxylate (3e).
mp 165–167 uC; 1H NMR (500 MHz, CDCl3): d: 7.72 (d, J =
8.5 Hz, 1H), 7.61 (d, J = 6.5 Hz, 1H), 7.36 (t, J = 7.5 Hz, 1H) 7.25–
7.08 (m, 10H), 6.86–6.70 (m, 10H), 3.17 (s, 3H); 13C NMR (125
MHz, CDCl3): d: 170.5, 141.3, 140.4, 140.1, 139.9, 139.5, 139.0,
137.2, 133.4, 132.4, 132.3, 131.4, 131.3, 131.1, 130.4, 128.7,
128.5, 127.7, 127.1, 126.8, 126.7, 126.6, 126.5, 125.6, 125.4,
124.6, 51.9; IR (KBr): 3078, 3055, 3043, 1722, 1599, 1564, 1495,
1443, 1271, 1192, 1134, 1086, 1026 cm21 HRMS calcd for
C36H26O2Na [M + Na]+: 513.1830 found 513.1830.
1,2,3,4-Tetraphenyltriphenylene (3h)5i. 1H NMR (500 MHz,
CDCl3): d: 8.44 (d, J = 8.0 Hz, 2H), 7.62 (d, J = 8.0 Hz, 2H), 7.41
(t, J = 7.5 Hz, 2H), 7.13–7.08 (m, 10H), 7.04 (t, J = 7.75 Hz, 2H)
6.95–6.87 (m, 6H), 6.72 (d, J = 6.5 Hz, 4H); 13C NMR (125 MHz,
CDCl3): d: 142.9, 140.53, 140.5, 137.3, 132.3, 131.7, 131.3,
130.9, 130.1, 128.1, 126.7, 126.5, 126.3, 125.6, 125.4, 123.3;
HRMS calcd for C42H29 [M + H]+: 533.2269 found 533.2264.
1,2,3,4-Tetraphenylnaphthalene (3f)4a 1H NMR (500 MHz,
.
5,6,7,8-Tetraphenylnaphthalene-2-carbaldehyde (3i)4a
.
1H
CDCl3): d: 7.65 (dd, J = 3.5, 6.5 Hz, 2H), 7.39 (dd, J = 3.5, 6.5 Hz,
2H), 7.26–7.18 (m, 10H), 6.88–6.82 (m, 10H); 13C NMR (125
MHz, CDCl3): d: 140.7, 139.7, 139.0, 138.6, 132.2, 131.4, 127.7,
127.1, 126.7, 126.6, 126.0, 125.5.
NMR (500 MHz, CDCl3): d: 10.01 (s, 1H), 8.18 (s, 1H), 7.89
(d, J = 9.2 Hz, 1H), 7.78 (d, J = 9.0 Hz, 1H), 7.34–7.23 (m, 10H),
6.93–6.87 (m, 10H); 13C NMR (125 MHz, CDCl3): d: 192.6,
142.3, 140.4, 140.2, 140.1, 139.9, 138.9, 138.7, 135.2, 134.3,
134.0, 131.7, 131.4, 131.3, 131.2, 131.1, 128.4, 127.9, 127.8,
127.1, 126.9, 126.88, 126.85, 125.84, 125.8, 122.4; HRMS calcd
for C35H25O [M + H]+: 461.1905 found 461.1901.
Methyl 5,6,7,8-tetraphenylnaphthalene-2-carboxylate (3g)4a
.
1H NMR (500 MHz, CDCl3): d: 8.44 (s, 1H), 7.97 (d, J = 9.5 Hz,
1H), 7.71 (d, J = 9.5 Hz, 1H), 7.29–7.21 (m, 10H), 6.90–6.85 (m,
10H), 3.87 (s, 3H); 13C NMR (125 MHz, CDCl3): d: 167.4, 141.4,
This journal is ß The Royal Society of Chemistry 2013
RSC Adv.

View Article Online
Paper
RSC Advances
1,2,3,4-Tetraphenyl-6-(trifluoromethoxy)naphthalene (3k).
mp 170–172 uC; 1H NMR (500 MHz, CDCl3): d: 7.71 (d, J =
9.5 Hz, 1H), 7.49 (s, 1H), 7.29–7.21 (m, 11H), 6.90–6.83 (m,
10H); 13C NMR (125 MHz, CDCl3): d: 147.2, 140.4, 140.3, 140.2,
139.6, 139.2, 138.9, 138.7, 138.6, 132.8, 131.33, 131.30, 131.2,
130.7, 129.5, 127.9, 127.8, 126.9, 126.86, 126.82, 126.7, 125.7,
125.6, 121.7, 119.8, 117.8; IR (KBr): 3060, 1620, 1601, 1491,
1443, 1261, 1221, 1171, 1157, 1072, 1026 cm21; HRMS calcd
for C35H23F3ONa [M + Na]+: 539.1599 found 539.1599.
5-(Trifluoromethyl)-1,2,3,4-tetraphenylnaphthalene (3l)15
.
mp 178–180 uC; 1H NMR (500 MHz, CDCl3): d: 8.01 (d, J =
7.0 Hz, 1H), 7.89 (d, J = 8.5 Hz, 1H), 7.44 (t, J = 8.0 Hz, 1H),
7.30–7.08 (m, 10H), 6.90–6.73 (m, 10H); 13C NMR (125 MHz,
CDCl3): d: 142.8, 140.5, 140.4, 140.2, 139.9, 139.5, 139.3, 137.2,
133.9, 132.8, 132.2, 131.4, 131.05, 131.0, 128.9, 128.23, 128.18,
128.12, 128.1, 127.8, 127.0, 126.9, 126.7, 126.5, 126.4, 126.2,
125.6, 125.4, 123.9, 123.2; IR (KBr): 3055, 3032, 1601, 1493,
1443, 1352, 1286, 1182, 1163, 1138, 1121, 1099,1074, 1061,
1024 cm21; HRMS calcd for C35H23F3Na [M + Na]+: 523.1650
found 523.1649.
6-(Trifluoromethyl)-1,2,3,4-tetraphenylnaphthalene (3m)4a
.
1H NMR (500 MHz, CDCl3): d: 7.86 (s, 1H), 7.66 (d, J = 9.0
Hz, 1H), 7.44 (d, J = 8.0 Hz, 1H), 7.18–7.09 (m, 10H), 6.78–6.72
(m, 10H); 13C NMR (125 MHz, CDCl3): d: 141.2, 140.4, 140.1,
139.6, 139.0, 138.7, 138.6, 133.5, 131.3, 131.2, 128.5, 128.3,
127.9, 127.8, 127.6, 127.1, 126.9, 126.8, 125.8, 125.7, 125.6,
124.8, 124.78, 124.74, 123.5, 121.5; HRMS calcd for
Scheme 2 Plausible mechanism of annulation reaction.
C
35H23F3Na [M + Na]+: 523.1650 found 523.1651.
6-Fluoro-1,2,3,4-tetraphenylnaphthalene (3n)4a
.
1H NMR
1-(1,2,3,4-Tetraphenylnaphthalen-7-yl)ethanone (3j). mp
236–237 uC; 1H NMR (300 MHz, CDCl3): d: 8.28 (s, 1H), 7.93
(dd, J = 1.5, 8.9 Hz, 1H), 7.69 (d, J = 8.9 Hz, 1H), 7.26–7.18 (m,
10H), 6.89–6.84 (m, 10H), 2.47 (s, 3H); 13C NMR (75 MHz,
CDCl3): d: 198.3, 141.6, 140.2, 140.1, 139.9, 139.1, 138.8, 138.6,
134.4, 134.3, 131.5, 131.3, 131.2, 131.1, 129.5, 127.8, 127.0,
126.8, 125.7, 123.8, 26.6; IR (KBr): 3055, 3026, 1682, 1603,
(500 MHz, CDCl3): d: 7.43 (d, J = 9.0 Hz, 1H), 7.32–6.94 (m,
13H), 6.85–6.78 (m, 9H); 13C NMR (125 MHz, CDCl3): d: 160.7,
158.7, 141.9, 141.8, 140.9, 140.3, 140.1, 139.9, 139.6, 138.5,
135.1, 135.0, 134.53, 134.51, 131.4, 131.3, 131.2, 130.2, 130.1,
127.7, 126.9, 126.7, 126.6, 126.1, 125.9, 125.8, 125.6, 125.5,
123.6, 123.5, 122.2, 122.1, 111.8, 111.6; HRMS calcd for
C
34H23FNa [M + Na]+: 473.1681 found 473.1683.
1495, 1441, 1420, 1367, 1354, 1294, 1246, 1072, 1026 cm21
HRMS calcd for C36H27O [M + H]+: 475.2062 found 475.2055.
;
5,7-Bis(trifluoromethyl)-1,2,3,4-tetraphenylnaphthalene
(3o). mp 195–197 uC; 1H NMR (500 MHz, CDCl3): d: 8.11 (s,
1H), 8.08 (s, 1H), 7.26–7.01 (m, 10H), 6.86–6.80 (m, 6H), 6.74
(dd, J = 1.75, 7.75 Hz, 2H), 6.66–6.64 (m, 2H); 13C NMR (125
MHz, CDCl3): d: 145.0, 141.3, 140.7, 140.5, 139.8, 139.6, 138.3,
137.6, 133.3, 132.7, 131.6, 131.4, 131.3, 130.8, 130.7, 130.2,
129.6, 129.5, 128.6, 128.4, 128.1, 127.5, 127.3, 126.9, 126.8,
126.7, 126.4, 126.3, 126.0, 125.9, 125.8, 125.7, 125.5, 125.3,
124.8, 124.6, 123.8, 123.7, 122.7 122.5; IR (KBr): 3099, 1680,
1653, 1558, 1497, 1319, 1286, 1267, 1163, 1128, 1068, 1027
cm21; HRMS calcd for C36H22F6Na [M + Na]+: 591.1523 found
591.1524.
5,6,7,8-Tetra p-tolylnaphthalene-1-carbonitrile (3p). mp .
1
240 uC; H NMR (500 MHz, CDCl3): d: 7.90–7.86 (m, 2H), 7.35
(t, J = 8.0 Hz, 1H), 7.08–7.02 (m, 8H), 6.68–6.66 (m, 8H), 2.34 (s,
3H), 2.31 (s, 3H), 2.09 (s, 6H); 13C NMR (125 MHz, CDCl3): d:
142.7, 140.8, 139.4, 137.7, 137.4, 137.0, 136.99, 136.95, 136.3,
136.1, 135.8, 134.9, 134.8, 132.9, 132.7, 132.1, 131.1, 131.0,
130.8, 128.5, 128.4, 127.5, 127.3, 124.4, 117.9, 110.4, 21.6, 21.4,
21.2; IR (KBr): 3435, 3045, 3022, 2991, 2949, 2920, 2866, 2831,
2214, 1898, 1512, 1479, 1445, 1404, 1379, 1350, 1337, 1209,
Scheme 3
RSC Adv.
This journal is ß The Royal Society of Chemistry 2013

View Article Online
RSC Advances
Paper
1182, 1111, 1034, 1020 cm21; HRMS calcd for C39H32N [M +
H]+: 514.2535 found 514.2529.
1485, 1441, 1385, 1367, 1238, 1099, 1070, 1026 cm21; HRMS
calcd for C36H26N [M + H]+: 472.2065 found 472.2060.
5,6,7,8-Tetraphenylisoquinoline (3x)4a 1H NMR (500 MHz,
.
5,6,7,8-Tetra p-tolylnaphthalene-2-carbonitrile (3q). mp .
1
CDCl3): d: 9.04 (s, 1H), 8.44 (d, J = 5.5 Hz, 1H), 7.48 (d, J = 6.0
Hz, 1H), 7.29–7.17 (m, 10H), 6.90–6.81 (m, 10H); 13C NMR (125
MHz, CDCl3): d: 151.4, 143.8, 142.1, 140.9, 139.7, 139.5, 139.4,
137.9, 137.7, 137.4, 135.1, 131.3, 131.26, 131.2, 130.9, 127.98,
127.9, 127.3, 127.2, 126.9, 126.1, 125.9, 119.6; HRMS calcd for
240 uC; H NMR (500 MHz, CDCl3): d: 8.00 (s, 1H), 7.68 (d, J =
9.0 Hz, 1H), 7.45 (dd, J = 1.5, 9.0 Hz, 1H), 7.08–7.02 (m, 8H),
6.68 (s, 8H), 2.34 (s, 3H), 2.32 (s, 3H) 2.11 (s, 6H); 13C NMR (125
MHz, CDCl3): d: 142.5, 141.1, 139.2, 138.7, 137.1, 136.9, 136.6,
136.4, 135.8, 135.4, 135.03, 135.0, 133.8, 133.6, 131.6, 131.1,
131.0, 130.9, 130.8, 128.7, 128.6, 128.4, 127.6, 127.5, 125.9,
119.9, 108.9, 21.4, 21.2; IR (KBr): 3045, 3020, 2993, 2968, 2729,
2221, 1900, 1609, 1558, 1514, 1487, 1441, 1402, 1371, 1292,
1213, 1184, 1107, 1080, 1035, 1024 cm21; HRMS calcd for
C39H31NNa [M + Na]+: 536.2354 found 536.2355.
C
33H24N [M + H]+: 434.1903 found 434.1903.
7,8,9,10-Tetraphenylphenanthridine (3y). mp . 200 uC; 1H
NMR (500 MHz, CDCl3): d: 9.01 (s, 1H), 8.03(d, J = 8.0 Hz, 1H),
7.48 (t, J = 7.25 Hz, 1H), 7.26 (d, J = 8.5 Hz, 1H), 7.23–7.07 (m,
10H), 7.02 (t, J = 7.75 Hz, 1H) 6.82–6.70 (m,10H); 13C NMR (125
MHz, CDCl3): d: 152.9, 145.7, 145.2, 141.9, 140.9, 140.7, 139.9,
139.7, 138.0, 137.9, 131.5, 131.2, 131.1, 130.9, 130.7, 129.9,
128.7, 128.1, 127.8, 127.6, 127.2, 127.1, 126.9, 126.7, 125.8,
125.7, 125.6, 124.5; IR (KBr): 3055, 3024, 1599, 1585, 1493,
.
5-Methyl-1,2,3,4-tetraphenylnaphthalene (3r)4a 1H NMR
(500 MHz, CDCl3): d: 7.52 (dd, J = 1.5, 8.0 Hz, 1H), 7.28–7.10
(m, 12H), 6.93–6.75 (m, 10H), 1.96 (s, 3H); 13C NMR (125 MHz,
CDCl3): d: 143.1, 140.9, 140.8, 140.6, 140.5, 138.6, 138.2, 136.1,
131.8, 131.5, 131.4, 131.3, 131.1, 130.4, 127.6, 126.9, 126.6,
126.5, 126.4, 126.3, 125.6, 125.3, 125.1, 25.4; HRMS calcd for
C35H27 [M + H]+: 447.2113 found 447.2108.
1439, 1394, 1332, 1072, 1026 cm21; HRMS calcd for C37H26
[M + H]+: 484.2065 found 484.2060.
N
6-Methyl-1,2,3,4-tetraphenylnaphthalene (3s)4a
.
1H NMR
(500 MHz, CDCl3): d: 7.52 (d, J = 9.0 Hz, 1H), 7.39 (s, 1H),
7.25–7.16 (m, 11H), 6.86–6.79 (m, 10H) 2.38 (s, 3H); 13C NMR
(125 MHz, CDCl3): d: 140.8, 140.7, 139.9, 139.1, 138.3, 138.1,
137.9, 135.7, 132.3, 131.5, 131.48, 131.43, 131.2, 130.4, 128.2,
127.6, 127.0, 126.6, 126.5, 125.9, 125.4, 21.9; HRMS calcd for
C35H27 [M + H]+: 447.2113 found 447.2106.
Acknowledgements
A.B and A.C are thankful to DST and CSIR, India, for research
fellowships. The authors thank Mr. Ranjan Dutta of the
Department of Inorganic Chemistry, IACS, and DST-funded
National Single Crystal Diffractometer Facility of IACS for
crystal structure determination.
5-Methoxy-1,2,3,4-tetraphenylnaphthalene (3t). mp . 200
uC; 1H NMR (500 MHz, CDCl3): d: 7.31 (t, J = 8.0 Hz, 1H), 7.26–
7.17 (m, 6H), 7.11–7.02 (m, 5H), 6.85–6.77 (m, 11H), 3.38 (s,
3H); 13C NMR (125 MHz, CDCl3): d: 157.4, 144.0, 140.7, 140.3,
140.0, 139.6, 138.3, 136.8, 134.3, 131.6, 131.4, 131.3, 129.9,
127.6, 126.6, 126.5, 126.3, 126.1, 125.3, 125.1, 124.9, 123.9,
120.3, 107.1, 55.9; IR (KBr): 3074, 3057, 300, 1599, 1560, 1547,
1491, 1450, 1441, 1425, 1373, 1354, 1257, 1234, 1115, 1057,
1026, 1003 cm21; HRMS calcd for C35H27O [M + H]+: 463.2062
found 463.2056.
Notes and references
1 (a) J. E. Anthony, Angew. Chem., Int. Ed., 2008, 47, 452; (b)
M. Bendikov, F. Wudl and D. F. Perepichka, Chem. Rev.,
2004, 104, 4841.
2 J. Wu, W. Pisula and M. Mu¨llen, Chem. Rev., 2007, 107, 718.
3 (a) T.-A. Chen and R.-S. Liu, Chem.–Eur. J., 2011, 17, 8023;
ˇ
´
(b) Z. Wang, Z. Tomovic, M. Kastler, R. Pretsch, F. Negri,
6-Methoxy-1,2,3,4-tetraphenylnaphthalene (3u)4a 1H NMR
.
V. Enkelmann and K. Mu¨llen, J. Am. Chem. Soc., 2004, 126,
(500 MHz, CDCl3): d: 7.55 (d, J = 9.0 Hz, 1H), 7.25–7.15 (m,
10H), 7.06 (dd, J = 2.5, 9.0 Hz, 1H), 6.94 (d, J = 2.5 Hz, 1H) 6.86–
6.79 (m, 10H), 3.68 (s, 3H). 13C NMR (125 MHz, CDCl3): d:
157.7, 140.8, 140.7, 139.9, 139.8, 139.5, 138.5, 137.4, 136.9,
133.4, 132.4, 131.6, 131.4, 131.3, 128.8, 127.7, 127.6, 126.6,
126.5, 125.4, 125.3, 118.1, 105.8, 55.3; HRMS calcd for
C35H26ONa [M + Na]+: 485.1881 found 485.1881.
¨
7794; (c) F. Dotz, J. D. Brand, S. Ito, L. Gherghel and
K. Mu¨llen, J. Am. Chem. Soc., 2000, 122, 7707; (d) M. Mu¨ller,
C. Ku¨bel and K. Mu¨llen, Chem.–Eur. J., 1998, 4, 2099.
4 (a) T. Fukutani, K. Hirano, T. Satoh and M. Miura, J. Org.
Chem., 2011, 76, 2867; (b) N. Guimond, C. Gouliaras and
K. Fagnou, J. Am. Chem. Soc., 2010, 132, 6908; (c)
T. Fukutani, K. Hirano, T. Satoh and M. Miura, Org. Lett.,
2009, 11, 5198; (d) M. Miyamoto, Y. Harada, M. Tobisu and
N. Chatani, Org. Lett., 2008, 10, 2975; (e) Y. Harada,
J. Nakanishi, H. Fujihara, M. Tobisu, Y. Fukumoto and
N. Chatani, J. Am. Chem. Soc., 2007, 129, 5766; (f) D. Suzuki,
R. Tanaka, H. Urabe and F. Sato, J. Am. Chem. Soc., 2002,
124, 3518.
5 (a) Y.-D. Lin, C.-L. Cho, C.-W. Ko, A. Pulte and Y.-T. Wu, J.
Org. Chem., 2012, 77, 9979; (b) H. Huang, J. Li, W. Zhao,
Y. Mei and Z. Duan, Org. Biomol. Chem., 2011, 9, 5036; (c)
T.-A. Chen and R.-S. Liu, Org. Lett., 2011, 13, 4644; (d)
J. Wu, X. Cui, X. Mi, Y. Li and Y. Wu, Chem. Commun., 2010,
46, 6771; (e) C. Wang, S. Rakshit and F. Glorius, J. Am.
Chem. Soc., 2010, 132, 14006; (f) C.-C. Hsiao, Y.-K. Lin, C.-
J. Liu, T.-C. Wu and Y.-T. Wu, Adv. Synth. Catal., 2010, 352,
4,5,6,7-Tetraphenylbenzo[b]thiophene (3v)5b 1H NMR (500
.
MHz, CDCl3): d: 7.37 (d, J = 5.5 Hz, 1H), 7.31–7.15 (m, 11H),
6.89–6.83 (m, 10H); 13C NMR (125 MHz, CDCl3): d: 140.8,
140.4, 140.3, 140.1, 140.0, 138.6, 137.9, 137.1, 136.1, 135.2,
131.9, 131.8, 130.7, 130.1, 128.1, 127.7, 127.2, 126.85, 126.83,
126.6, 125.6, 125.5, 124.8.
6,7,8,9-Tetraphenyl-3H-benzo[e]indole (3w). mp . 240 uC;
1H NMR (500 MHz, CDCl3): d: 8.33 (s, 1H), 7.44 (s, 2H), 7.29–
7.17 (m, 10H), 6.91–6.79 (m, 11H), 5.12 (s, 1H); 13C NMR (125
MHz, CDCl3): d: 142.5, 141.2, 141.1, 140.9, 139.5, 139.2, 137.1,
136.7, 133.5, 131.7, 131.6, 131.3, 128.3, 128.1, 127.5, 126.9,
126.7, 126.5, 126.4, 126.3, 125.2, 125.1, 122.6, 122.5, 120.9,
112.9, 106.2; IR (KBr): 3400, 3360, 3076, 3055, 3022, 1599,
This journal is ß The Royal Society of Chemistry 2013
RSC Adv.

View Article Online
Paper
3267; (g) K.-T. Chan, Y.-H. Tsai, W.-S. Lin, J.-R. Wu, S.-
RSC Advances
7 (a) W. Han, C. Liu and Z.-L. Jin, Org. Lett., 2007, 9, 4005; (b)
D. Srimani, A. Bej and A. Sarkar, J. Org. Chem., 2010, 75,
4296; (c) A. Bej, D. Srimani and A. Sarkar, Green Chem.,
2012, 14, 661.
8 R. C. Larock, M. J. Doty and X. Han, J. Org. Chem., 1999, 64,
8770.
9 In ref. 5q, it was stated that: ‘‘p-Nitroiodobenzene,
o-iodoaniline, p-iodo-N,N-dimethylaniline, and 2-iodo-1,4-
dimethoxybenzene with diphenylacetylene gave complex
product mixtures and we were unable to isolate pure
products from any of these’’.
J. Chen, F.-X. Liao, C.-H. Hu and H. M. Lee,
Organometallics, 2010, 29, 463; (h) Z. Shi, S. Ding, Y. Cui
and N. Jiao, Angew. Chem., Int. Ed., 2009, 48, 7895; (i) Y.-
T. Wu, K.-H. Huang, C.-C. Shin and T.-C. Wu, Chem.–Eur. J.,
2008, 14, 6697; (j) D. V. Kadnikov and R. C. Larock, J.
Organomet. Chem., 2003, 687, 425; (k) S. Kawasaki, T. Satoh,
M. Miura and M. Nomura, J. Org. Chem., 2003, 68, 6836; (l)
R. C. Larock and Q. Tian, J. Org. Chem., 2001, 66, 7372; (m)
˜
R. C. Larock, Pure Appl. Chem., 1999, 71, 1435; (n) D. Pena,
´
´
D. Perez, E. Guitian and L. Castedo, Org. Lett., 1999, 1,
1555; (o) R. C. Larock, M. J. Doty and X. Han, J. Org. Chem.,
1999, 64, 8770; (p) R. C. Larock and M. J. Doty, J. Org.
Chem., 1993, 58, 4579; (q) G. Wu, A. L. Rheingold, S. J. Geib
and R. F. Heck, Organometallics, 1987, 6, 1941; (r) G. Wu, A.
L. Rheingold and R. F. Heck, Organometallics, 1986, 5,
1922; (s) T. Sakakibara, Y. Tanaka and S.-I. Yamasaki,
Chem. Lett., 1986, 15, 797.
10 Y. Yuan and Y. Bian, Appl. Organomet. Chem., 2008, 22, 15.
¨
11 C. F. Nising, U. K. Schmid, M. Nieger and S. Brase, J. Org.
Chem., 2004, 69, 6830.
12 P. Sehnal, R. J. K. Taylor and I. J. S. Fairlamb, Chem. Rev.,
2010, 110, 824.
13 J. Chen, S. K. Spear, J. G. Huddleston and R. D. Rogers,
Green Chem., 2005, 7, 64.
14 G. F. Morrision and J. Hooz, J. Org. Chem., 1970, 35, 1196.
15 B. Baigrie, J. I. G. Cadogan, J. R. Mitchell, A. K. Robertson
and J. T. Sharp, J. Chem. Soc., Perkin Trans. 1, 1972, 2563.
6 (a) R. C. Larock and Q. Tian, J. Org. Chem., 2001, 66, 7372;
(b) Q. Tian and R. C. Larock, Org. Lett., 2000, 2, 3329; (c)
G. Dyker and A. Kellner, Tetrahedron Lett., 1994, 35, 7633;
(d) G. Dyker, J. Org. Chem., 1993, 58, 234; (e) S. Cacchi,
M. Felici and B. Pietroni, Tetrahedron Lett., 1984, 25, 3137.
RSC Adv.
This journal is ß The Royal Society of Chemistry 2013