Synthesis of triphenylene derivatives by rhodium-catalyzed [2 + 2 + 2] cycloaddition: Application to the synthesis of highly fluorescent triphenylene-based long ladder molecules

Article abstract of DOI:10.1021/jo4008892

The convenient synthesis of substituted triphenylenes and azatriphenylenes has been achieved by the cationic rhodium(I)/H₈-BINAP or BINAP complex-catalyzed [2 + 2 + 2] cycloaddition under mild conditions. Photophysical properties of representat

Full text of DOI:10.1021/jo4008892

Article
pubs.acs.org/joc
Synthesis of Triphenylene Derivatives by Rhodium-Catalyzed [2 + 2 +
2] Cycloaddition: Application to the Synthesis of Highly Fluorescent
Triphenylene-Based Long Ladder Molecules
Koichi Murayama,† Yayoi Sawada,† Keiichi Noguchi,‡ and Ken Tanaka*,†,§
‡
†Department of Applied Chemistry, Graduate School of Engineering and Instrumentation Analysis Center, Tokyo University of
Agriculture and Technology, Koganei, Tokyo 184-8588, Japan
§JST, ACT-C, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
S
* Supporting Information
ABSTRACT: The convenient synthesis of substituted tri-
phenylenes and azatriphenylenes has been achieved by the
cationic rhodium(I)/H8-BINAP or BINAP complex-catalyzed
[2 + 2 + 2] cycloaddition under mild conditions. Photo-
physical properties of representative triphenylenes and azatri-
phenylenes were examined, which revealed that azatriphenyl-
enes showed higher fluorescence quantum yields than
triphenylenes. This method was successfully applied to the
synthesis of highly fluorescent triphenylene-based long ladder
molecules.
phenylenes by using the cationic rhodium(I)/H8-BINAP or
BINAP complex as a catalyst (Scheme 2). Recently, our
research group reported the rhodium-catalyzed enantioselective
synthesis and photophysical properties of helically chiral 1,1′-
bitriphenylenes.15 In this paper, we disclose the rhodium-
catalyzed synthesis and photophysical properties of substituted
azatriphenylenes, as well as triphenylenes. The application of
this method to the synthesis of highly fluorescent triphenylene-
based long ladder molecules is also disclosed.
INTRODUCTION
■
Triphenylene derivatives have attracted much attention in
supramolecular and materials chemistry because of their rigid,
planar, and conjugated structures and also their self-assembling
character.1 For example, triphenylenes possessing long aliphatic
side chains form discotic liquid crystals as a result of their self-
assembly.2 Numbers of substituted triphenylenes have been
synthesized, and their physical properties have been inves-
tigated to date,1,2 while synthetic methods3,4 of substituted
azatriphenylenes have not been well investigated and no report
has been published for their physical properties. As the
transition-metal-catalyzed synthesis of substituted triphenyl-
enes, the homo-[2 + 2 + 2] cycloaddition of three benzynes
leading to symmetrically substituted triphenylenes has been
reported.5 For the transition-metal-catalyzed synthesis of
unsymmetrically substituted triphenylenes, the Deiters group
reported the [2 + 2 + 2] cycloaddition of a biaryl-linked diyne
with alkynes using a nickel catalyst.4 Importantly, this method
could be applied to the synthesis of substituted azatriphenyl-
enes by using a cobalt catalyst.4 However, these reactions
employed high reaction temperatures under microwave
irradiation. On the other hand, our research group reported
that the cationic rhodium(I)/H8-BINAP or BINAP complex is
able to catalyze the [2 + 2 + 2] cycloadditions6,7 of 1,7-
octadiyne derivatives with alkynes,8,9 nitriles,10,11 and iso-
cyanates12,13 leading to 6−6 fused carbocycles and heterocycles
under mild conditions despite the absence of the Thorpe−
Ingold effect14 (Scheme 1).
RESULTS AND DISCUSSION
■
We first examined the substituted triphenylene synthesis, as
shown in Table 1. Pleasingly, the reaction of biaryl-linked
terminal diyne 1a and ethyl 2-butynoate (2a, 1.1 equiv)
proceeded in the presence of the cationic rhodium(I)/H8-
BINAP complex (5 mol %) at room temperature to give the
corresponding triphenylene 3aa in high yield. The use of
BINAP in place of H8-BINAP afforded 3aa in lower yield.
Various electron-deficient unsymmetrical internal alkynes 2b−f
were able to react with 1a to give the corresponding
triphenylenes in good to high yields. Electron-rich propargyl
alcohols 2g,h were also suitable substrates for this process. For
highly electron-deficient internal alkyne 2i and terminal alkyne
2j,16 excess alkynes (2 equiv) were employed due to
consumption of these alkynes by the undesired homo-[2 + 2
+ 2] cycloaddition. In the case of 2i, the use of BINAP in place
of H8-BINAP improved the product yield. Biaryl-linked internal
diyne 1b was also a suitable substrate for this process. Diyne 1b
These results prompted our investigation into the [2 + 2 + 2]
cycloadditions of biaryl-linked diynes with alkynes, nitriles, and
isocyanates leading to substituted triphenylenes and azatri-
Received: April 25, 2013
Published: May 21, 2013
© 2013 American Chemical Society
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Scheme 1. Rhodium-Catalyzed [2 + 2 + 2] Cycloadditions of 1,7-Octadiyne Derivatives with Alkynes, Nitriles, and Isocyanates
Scheme 2. Rhodium-Catalyzed [2 + 2 + 2] Cycloadditions of Biaryl-Linked Diynes with Alkynes, Nitriles, and Isocyanates
reacted with both electron-deficient and -rich internal alkynes
2a,g to give the corresponding triphenylenes in high yields.
We next examined the substituted azatriphenylene synthesis,
as shown in Table 2. The reaction of the terminal diyne 1a and
acetonitrile (4a) proceeded at room temperature in the
presence of the cationic rhodium(I)/BINAP complex (5 mol
%) to give the corresponding azatriphenylene 5aa in good yield.
Both primary and secondary aliphatic nitriles 4b,c could also
participate in this reaction. Not only aliphatic nitriles but also
aromatic nitriles 4d−g16 reacted with 1a at room temperature
to give the corresponding conjugated azatriphenylenes in good
yields. Diyne 1a selectively reacted with the cyano group of
acrylonitrile (4h) to give vinylazatriphenylene 5ah in high
yield.10 Although elevated reaction temperature (80 °C) was
required, the reactions of activated nitriles 4i−k and 1a
proceeded to give the corresponding azatriphenylenes in
moderate to good yields. The internal diyne 1b also reacted
with 4d and 4i at 80 °C to give the corresponding
azatriphenylenes 5bd and 5bi in moderate to high yields.
Because the reactivity of nitriles 4 was lower than that of
alkynes 2, the yields of azatriphenylenes 5 were generally lower
compared to triphenylenes 3, and as a result, excess nitriles (5
equiv) were used in some cases.
and emission maxima compared with triphenylenes 3.
Ethoxycarbonyl or diethoxyphosphinyl-substituted triphenyl-
enes 3ad, 3af, and 3ai showed higher fluorescence quantum
yields (9.7−12.4%) than triphenylene-methanols 3ag and 3ah
(2.9−3.0%), and that of diethoxyphosphinyl-substituted tri-
phenylenes 3af was the highest (12.4%).18 In general,
azatriphenylenes 5 showed higher fluorescence quantum yields
(11.7−30.6%) than triphenylenes 3 (2.9−12.4%) and azatri-
phenylene 7b (5.5%). Especially, π-extended 4-methoxyphenyl-
and 4-cyanophenyl-substituted azatriphenylenes 5af and 5ag
showed promising high fluorescence quantum yields (23.0 and
30.6%, respectively).
The present rhodium-catalyzed [2 + 2 + 2] cycloaddition of
biaryl-linked diynes with alkynes was successfully applied to the
synthesis of triphenylene-based ladder molecules. The reaction
of the terminal diyne 1a with phenyl-substituted propargyl
alcohol 2k in the presence of the cationic rhodium(I)/H8-
BINAP catalyst at room temperature afforded triphenylene 3ak.
Subsequent dehydration afforded triphenylene 8ak, containing
a fluorene skeleton, in good yield (Scheme 4). The rhodium-
catalyzed double [2 + 2 + 2] cycloaddition of 1a with benzene-
linked bispropargyl alcohol 2l followed by dehydration afforded
triphenylene-based ladder molecule 8al19 in good yield
(Scheme 5).
Not only nitriles but also n-butylisocyanate (6) could be
employed, as shown in Scheme 3. The internal diyne 1b reacted
with 6 in the presence of the cationic rhodium(I)/H8-BINAP
catalyst at room temperature to give the corresponding
azatriphenylene 7b in excellent yield.17
Longer ladder molecule 8am19,20 was also synthesized in
good yield by the rhodium-catalyzed double [2 + 2 + 2]
cycloaddition of 1a with fluorene-linked bispropargyl alcohol
2m followed by dehydration (Scheme 6).
Absorption and emission data of representative triphenylenes
and azatriphenylenes in CHCl3 are shown in Table 3.
Azatriphenylenes 5 and 7b showed red shifts of absorption
Single-crystal X-ray analyses of these ladder molecules 8al
and 8am showed that the conjugated triphenylene-fluorene
cores are almost flat as shown in the Supporting Information
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a
Table 1. Synthesis of Triphenylenes by Rhodium-Catalyzed [2 + 2 + 2] Cycloaddition
a
[Rh(cod)2]BF4 (0.0050 mmol), H8-BINAP or BINAP (0.0050 mmol), 1 (0.10 mmol), 2 (0.11−0.20 mmol), and (CH2Cl)2 (2.0 mL) were used.
Cited yields are of isolated products.
(Figures S-7 and S-8, top). Ladder molecule 8al is stacked
along the b-axis with a mean interplanar distance of 3.51 Å
(Figure S-7, bottom). On the other hand, ladder molecule 8am
is cocrystallized with n-hexane and stacked along the a-axis with
a mean interplanar distance of 3.28 Å (Figure S-8, bottom).
Absorption and emission data of these triphenylene-based π-
conjugated molecules in CHCl3 are shown in Table 4. As
expected, longer π-conjugated molecules showed larger red
shifts of absorption and emission maxima. The fluorescence
quantum yields of 8al and 8am are very high in CHCl3: 88.1%
for 8al and 84.6% for 8am. Importantly, 8al and 8am also emit
in the solid state. The fluorescence quantum yields are 9.2% for
8al and 12.5% for 8am.
rhodium(I)/H8-BINAP or BINAP complex-catalyzed [2 + 2 +
2] cycloaddition under mild conditions. Photophysical proper-
ties of representative triphenylenes and azatriphenylenes were
examined, which revealed that azatriphenylenes showed higher
fluorescence quantum yields than triphenylenes. This method
was successfully applied to the synthesis of highly fluorescent
triphenylene-based long ladder molecules.
EXPERIMENTAL SECTION
■
General. Anhydrous CH2Cl2 (No. 27,099-7) and (CH2Cl)2 (No.
28,450-5) were obtained from Sigma-Aldrich and used as received.
Solvents for the synthesis of substrates were dried over molecular
sieves 4 Å (Wako) prior to use. H8-BINAP was obtained from
Takasago International Corporation. Diynes (1a,21,22 1b,23 and 2m24)
and monoynes (2c25 and 2k26) were prepared according to the
literature. All other reagents were obtained from commercial sources
CONCLUSION
■
In conclusion, we have achieved the convenient synthesis of
substituted triphenylenes and azatriphenylenes by the cationic
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a
Table 2. Synthesis of Azatriphenylenes by Rhodium-Catalyzed [2 + 2 + 2] Cycloaddition
a
[Rh(cod)2]BF4 (0.0050 mmol), BINAP (0.0050 mmol), 1 (0.10 mmol), 4 (0.11−0.50 mmol), and (CH2Cl)2 (2.0 mL) were used. Cited yields are
b
c
d
of isolated products. Catalyst: 10 mol %. Conv of 1a ≈ 85%. Conv of 1b ≈ 85%.
(10 mL) were added 1,4-diiodobenzene (0.402 g, 1.22 mmol) and 5-
Scheme 3. Rhodium-Catalyzed [2 + 2 + 2] Cycloaddition of
Biaryl-Linked Internal Diyne 1b with Isocyanate 6
ethynyl-5-nonanol (0.430 g, 2.56 mmol). The resulting mixture was
stirred at 60 °C for 4 h. The reaction mixture was filtered and
concentrated. The crude product was purified by a silica gel column
chromatography (hexane/EtOAc = 10:1) to give 2l (0.329 g, 0.800
mmol, 66% yield). Pale orange solid, mp 52.6−54.4 °C; IR (KBr)
1
3347, 3077, 2963, 2861, 1507, 1380 cm−1; H NMR (CDCl3, 300
MHz) δ 7.35 (s, 4H), 1.95 (s, 2H), 1.80−1.66 (m, 8H), 1.62−1.47 (m,
8H), 1.38 (sext, J = 7.2 Hz, 8H), 0.95 (t, J = 7.2 Hz, 12H); 13C NMR
(CDCl3, 125 MHz) δ 131.5, 122.7, 94.0, 83.9, 71.7, 41.8, 26.5, 22.9,
14.1; HRMS (ESI-TOF) calcd for C28H42O2Na [M + Na]+ 433.3077,
found 433.3071.
General Procedure for Rhodium-Catalyzed [2 + 2 + 2]
Cycloaddition. H8-BINAP or BINAP (0.0050 mmol) and [Rh-
(cod)2]BF4 (0.0050 mmol) were dissolved in CH2Cl2, and the mixture
and used as received. All reactions were carried out under an
atmosphere of argon in oven-dried glassware with magnetic stirring.
5-[4-(3-Butyl-3-hydroxyhept-1-ynyl)phenylethynyl]nonan-5-ol
(2l). To a stirred solution of PdCl2(PPh3)2 (8.6 mg, 0.012 mmol) and
CuI (9.3 mg, 0.049 mmol) in di-isopropylamine (30 mL) and toluene
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= 7.2 Hz, 2H), 3.19 (t, J = 7.8 Hz, 2H), 1.80−1.67 (m, 2H), 1.56−1.18
(m, 17H), 0.89 (t, J = 6.9 Hz, 3H); 13C NMR (CDCl3, 75 MHz) δ
167.9, 142.3, 132.1, 130.7, 129.5, 129.4, 128.8, 128.7, 128.0, 127.4,
127.3, 127.23, 127.21, 126.5, 125.3, 123.7, 123.3, 123.2, 61.0, 35.1,
32.1, 31.9, 29.9, 29.7, 29.63, 29.62, 29.3, 22.7, 14.4, 14.1; HRMS (ESI-
TOF) calcd for C31H36O2Na [M + Na]+ 463.2608, found 463.2611.
3-Phenyltriphenylene-2-carboxylic Acid Ethyl Ester (3ad): Color-
less solid, mp 156.0−157.9 °C, 35.3 mg (94%); IR (KBr) 3088, 2980,
2935, 1953, 1709, 1249 cm−1; 1H NMR (CDCl3, 300 MHz) δ 9.14 (s,
1H), 8.79−8.47 (m, 5H), 7.81−7.56 (m, 4H), 7.56−7.34 (m, 5H),
4.22 (q, J = 6.9 Hz, 2H), 1.09 (t, J = 6.9 Hz, 3H); 13C NMR (CDCl3,
75 MHz) δ 168.7, 141.8, 140.5, 131.7, 130.6, 129.8, 129.7, 129.1,
128.8, 128.7, 128.4, 128.1, 128.0, 127.6, 127.5, 127.3, 127.2, 125.8,
125.6, 123.8, 123.5, 123.4, 123.3, 61.1, 13.7; HRMS (ESI-TOF) calcd
for C27H20O2Na [M + Na]+ 399.1356, found 399.1356.
Table 3. Photophysical Properties of Representative
Triphenylenes and azatriphenylenes
a
UV absorption λmax
fluorescence λmax
entry compound
(nm)
(nm)
ϕF
1
2
3ad
3af
3ag
3ah
3ai
5ad
5ae
5af
5ag
5ai
7b
270
384
0.099
0.124
0.030
0.029
0.097
0.176
0.193
0.230
0.306
0.117
0.055
267
359, 375
369
3
266
4
266
368
5
269
365, 381
361, 379
360, 378
377, 387
363, 381
358, 375
498
6
274
7
274
8
259, 279
277
9
10
11
267
1-(3-Phenyltriphenylen-2-yl)ethanone (3ae): Colorless solid, mp
200.2−201.9 °C, 25.5 mg (74%); IR (KBr) 3070, 3031, 2925, 1959,
278, 288
1
1678, 761 cm−1; H NMR (CDCl3, 500 MHz) δ 8.85 (s, 1H), 8.74−
a
Measured in CHCl3 at 25 °C.
8.56 (m, 4H), 8.59 (s, 1H), 7.75−7.60 (m, 4H), 7.59−7.43 (m, 5H),
2.15 (s, 3H); 13C NMR (CDCl3, 125 MHz) δ 204.5, 141.0, 139.4,
138.9, 131.4, 130.6, 129.9, 129.2, 129.1, 128.9, 128.8, 128.6, 128.1,
128.0, 127.7, 127.5, 127.4, 125.3, 123.8, 123.7, 123.5, 123.4, 123.3,
30.6; HRMS (ESI-TOF) calcd for C26H18ONa [M + Na]+ 369.1250,
found 369.1256.
was stirred at room temperature for 10 min. H2 was introduced to the
resulting solution in a Schlenk tube. After being stirred at room
temperature for 1 h, the resulting solution was concentrated to
dryness. The residue was redissolved in (CH2Cl)2 (0.5 mL), and a
(CH2Cl)2 (0.5 mL) solution of 2, 4, or 6 (0.110−0.500 mmol) was
added. A (CH2Cl)2 (1.0 mL) solution of 1 (0.100 mmol) was added
dropwise to this solution, and the mixture was stirred at rt−80 °C for
16−72 h. The resulting solution was concentrated and purified by a
preparative TLC, which furnished 3, 5, or 7.
(3-Phenyltriphenylen-2-yl)phosphonic Acid Diethyl Ester (3af):
Colorless solid, mp 206.8−209.0 °C, 28.3 mg (64%); IR (KBr) 3073,
1
2980, 2864, 1599, 1242, 1032 cm−1; H NMR (CDCl3, 500 MHz) δ
9.40 (d, J = 16.0 Hz, 1H), 8.84−8.75 (m, 1H), 8.70−8.63 (m, 2H),
8.62 (d, J = 8.5 Hz, 1H), 8.56 (d, J = 5.0 Hz, 1H), 7.76−7.67 (m, 3H),
7.66−7.56 (m, 3H), 7.52−7.42 (m, 3H), 4.09−3.89 (m, 4H), 1.20 (t, J
= 7.0 Hz, 6H); 13C NMR (CDCl3, 125 MHz) δ 143.44, 143.37,
141.61, 141.58, 132.21, 132.18, 130.9, 130.5, 130.4, 129.8, 129.6,
129.0, 128.7, 128.3, 128.1, 127.9, 127.7, 127.6, 127.5, 127.4, 126.2,
126.1, 124.7, 123.8, 123.6, 123.4, 123.3, 61.95, 61.90, 16.14, 16.08; 31P
NMR (CDCl3, 202 MHz) δ 19.2; HRMS (ESI-TOF) calcd for
C28H25O3PNa [M + Na]+ 463.1434, found 463.1435.
(3-Phenyltriphenylen-2-yl)methanol (3ag): Colorless solid, mp
195.9−197.2 °C, 31.6 mg (94%); IR (KBr) 3339, 3052, 2927, 2242,
1601, 1438 cm−1; 1H NMR (CDCl3, 500 MHz) δ 8.82 (s, 1H), 8.77−
8.71 (m, 1H), 8.70−8.64 (m, 2H), 8.62 (d, J = 8.0 Hz, 1H), 8.52 (s,
1H), 7.76−7.59 (m, 4H), 7.57−7.43 (m, 5H), 4.87 (s, 2H), 1.79 (br,
1H); 13C NMR (CDCl3, 75 MHz) δ 140.7, 140.2, 137.2, 130.0, 129.8,
129.47, 129.46, 129.3, 129.1, 129.0, 128.4, 127.5, 127.3, 127.2, 124.9,
123.44, 123.36, 123.3, 122.9, 63.6; HRMS (ESI-TOF) calcd for
C25H18ONa [M + Na]+ 357.1250, found 357.1255.
3-Methyltriphenylene-2-carboxylic Acid Ethyl Ester (3aa): Color-
less solid, mp 118.3−119.1 °C, H8-BINAP 28.1 mg (89%), BINAP
24.0 mg (76%); IR (KBr) 3074, 2973, 1710, 1271, 1095, 753 cm−1; 1H
NMR (CDCl3, 300 MHz) δ 9.13 (s, 1H), 8.66−8.47 (m, 4H), 8.32 (s,
1H), 7.72−7.54 (m, 4H), 4.49 (q, J = 7.2 Hz, 2H), 2.80 (s, 3H), 1.51
(t, J = 7.2 Hz, 3H); 13C NMR (CDCl3, 75 MHz) δ 167.6, 137.7, 132.1,
130.6, 129.4, 129.3, 128.6, 128.5, 127.9, 127.30, 127.25, 127.2, 126.3,
125.9, 123.7, 123.3, 123.2, 123.1, 60.9, 22.3, 14.5; HRMS (ESI-TOF)
calcd for C22H18O2Na [M + Na]+ 337.1199, found 337.1194.
3-Butyltriphenylene-2-carboxylic Acid Ethyl Ester (3ab): Colorless
solid, mp 85.0−85.9 °C, 30.9 mg (87%); IR (KBr) 3078, 2952, 1719,
1
1269, 1086, 752 cm−1; H NMR (CDCl3, 300 MHz) δ 9.15 (s, 1H),
8.69−8.55 (m, 4H), 8.42 (s, 1H), 7.72−7.59 (m, 4H), 4.50 (q, J = 7.2
Hz, 2H), 3.20 (t, J = 7.8 Hz, 2H), 1.81−1.67 (m, 2H), 1.58−1.42 (m,
5H), 1.01 (t, J = 7.2 Hz, 3H); 13C NMR (CDCl3, 75 MHz) δ 167.9,
142.3, 132.1, 130.6, 129.5, 129.4, 128.8, 128.7, 127.9, 127.4, 127.3,
127.22, 127.20, 126.5, 125.3, 123.7, 123.3, 123.2, 61.0, 34.8, 34.2, 22.9,
14.4, 14.1; HRMS (ESI-TOF) calcd for C25H24O2Na [M + Na]+
379.1669, found 379.1674.
(3-Trimethylsilanyltriphenylen-2-yl)methanol (3ah): Colorless
solid, mp 151.7−152.3 °C, 30.6 mg (93%); IR (KBr) 3276, 3085,
2941, 1606, 1245, 839 cm−1;1H NMR (CDCl3, 300 MHz) δ 8.81 (s,
1H), 8.76−8.54 (m, 5H), 7.73−7.58 (m, 4H), 5.02 (s, 2H), 1.93 (br,
1H), 0.50 (s, 9H); 13C NMR (CDCl3, 125 MHz) δ 144.5, 136.6,
130.3, 130.2, 130.0, 129.7, 129.6, 129.4, 127.8, 127.4, 127.2, 127.1,
3-Decyltriphenylene-2-Carboxylic Acid Ethyl Ester (3ac). Color-
less solid, mp 80.5−81.4 °C, 39.4 mg (89%); IR (KBr) 3078, 2923,
1
1721, 1271, 1091, 754 cm−1; H NMR (CDCl3, 300 MHz) δ 9.16 (s,
1H), 8.69−8.56 (m, 4H), 8.43 (s, 1H), 7.72−7.60 (m, 4H), 4.50 (q, J
Scheme 4. Rhodium-Catalyzed [2 + 2 + 2] Cycloaddition of Biaryl-Linked Terminal Diyne 1a with Phenyl-Substituted
Propargyl Alcohol 2k
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Scheme 5. Rhodium-Catalyzed [2 + 2 + 2] Cycloaddition of Biaryl-Linked Terminal Diyne 1a with Phenyl-Substituted
Bispropargyl Alcohol 2l
Scheme 6. Rhodium-Catalyzed [2 + 2 + 2] Cycloaddition of Biaryl-Linked Terminal Diyne 1a with Fluorene-Substituted
Bispropargyl Alcohol 2m
2-Decyltriphenylene (3aj): Colorless solid, mp 57.7−59.5 °C, 26.8
Table 4. Photophysical Properties of Triphenylene-Based π-
Conjugated Molecules
1
mg (73%); IR (KBr) 3071, 2919, 2849, 1620, 1469, 745 cm−1; H
a
NMR (CDCl3, 300 MHz) δ 8.78−8.59 (m, 4H), 8.57 (d, J = 8.4 Hz,
1H), 8.45 (d, J = 1.5 Hz, 1H), 7.77−7.58 (m, 4H), 7.50 (dd, J = 8.4,
1.5 Hz, 1H), 2.87 (t, J = 7.5 Hz, 2H), 1.79 (quint, J = 7.5 Hz, 2H),
1.51−1.20 (m, 14H), 0.89 (t, J = 6.9 Hz, 3H); 13C NMR (CDCl3, 75
MHz) δ 141.9, 129.9, 129.8, 129.7, 129.4, 128.0, 127.7, 127.4, 127.1,
127.03, 127.02, 126.7, 123.27, 123.25, 123.2, 123.1, 122.7, 36.3, 31.9,
31.6, 29.62, 29.57, 29.4, 29.3, 22.7, 14.1; HRMS (APCI-TOF) calcd
for C28H33 [M + H]+ 369.2577, found 369.2592.
UV absorption λmax fluorescence λmax
entry compound
(nm)
(nm)
ϕF
1
2
8ak
8al
278
392
362, 381
396, 419
0.265
0.859
(0.092 )
0.881
(0.125 )
b
3
8am
407
412, 437
b
a
b
Measured in CHCl3 at 25 °C. Fluorescence quantum yields in the
1,3,4-Trimethyltriphenylene-2-carboxylic Acid Ethyl Ester (3ba):
Colorless solid, mp 171.6−173.9 °C, 33.9 mg (99%); IR (KBr) 3412,
solid state.
1
3063, 2970, 2865, 1721, 1221 cm−1; H NMR (CDCl3, 300 MHz) δ
8.62−8.36 (m, 2H), 8.33−8.06 (m, 2H), 7.79−7.36 (m, 4H), 4.51 (q, J
= 7.5 Hz, 2H), 2.85 (s, 3H), 2.79 (s, 3H), 2.42 (s, 3H), 1.47 (t, J = 7.5
Hz, 3H); 13C NMR (CDCl3, 125 MHz) δ 171.1, 135.2, 133.9, 131.3,
131.1, 130.8, 130.7, 130.6, 130.5, 130.3, 129.0, 128.2, 126.9, 126.7,
126.6, 126.1, 125.9, 123.4, 61.2, 21.39, 21.37, 17.4, 14.3; HRMS (ESI-
TOF) calcd for C24H22O2Na [M + Na]+ 365.1512, found 365.1512.
(1,4-Dimethyl-3-phenyltriphenylen-2-yl)methanol (3bg): Color-
less solid, mp 87.3−89.0 °C, 32.4 mg (89%); IR (KBr) 3578, 3386,
127.0, 123.35, 123.27, 123.2, 123.0, 121.6, 65.6, 0.4; HRMS (ESI-
TOF) calcd for C22H22OSiNa [M + Na]+ 353.1332, found 353.1342.
Triphenylene-2,3-dicarboxylic Acid Diethyl Ester (3ai): A
(CH2Cl)2 solution of 1a and 2i was added dropwise to a (CH2Cl)2
solution of the Rh catalyst. Colorless solid, mp 106.9−108.4 °C, 28.3
1
mg (76%); IR (KBr) 3081, 2980, 2937, 2904, 1721, 1251 cm−1; H
NMR (CDCl3, 300 MHz) δ 8.97 (s, 2H), 8.75−8.57 (m, 4H), 7.79−
7.63 (m, 4H), 4.49 (q, J = 7.2 Hz, 4H), 1.47 (t, J = 7.2 Hz, 6H); 13C
NMR (CDCl3, 75 MHz) δ 167.9, 131.3, 130.5, 130.0, 128.6, 128.5,
127.6, 124.8, 123.9, 123.4, 61.8, 14.2; HRMS (ESI-TOF) calcd for
C24H20O4Na [M + Na]+ 395.1254, found 395.1255.
1
3062, 2922, 1725, 1439 cm−1; H NMR (CDCl3, 300 MHz) δ 8.52
(dd, J = 8.1, 1.5 Hz, 2H), 8.31 (dt, J = 8.1, 1.5 Hz, 2H), 7.68−7.40 (m,
7H), 7.38−7.29 (m, 2H), 4.61 (s, 2H), 3.05 (s, 3H), 2.55 (s, 3H), 1.42
6207
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(br, 1H); 13C NMR (CDCl3, 75 MHz) δ 142.2, 141.1, 135.9, 133.05,
132.96, 131.1, 130.92, 130.90, 130.8, 129.6, 129.3, 128.9, 128.6, 127.2,
126.7, 126.6, 125.95, 125.92, 123.45, 123.42, 61.0, 23.5, 20.7; HRMS
(ESI-TOF) calcd for C27H22ONa [M + Na]+ 385.1563, found
385.1568.
123.40, 123.39, 122.5, 117.9, 114.1; HRMS (ESI-TOF) calcd for
C19H14N [M + H]+ 256.1121, found 256.1126.
2-Azatriphenylene-3-carboxylic Acid Ethyl Ester (5ai): Colorless
solid, mp 170.1−171.6 °C, 4i: 1.1 equiv, 19.6 mg (65%), 4i: 5 equiv,
25.9 mg (86%); IR (KBr) 3076, 2976, 2869, 1712, 1262, 1129 cm−1;
1H NMR (CDCl3, 300 MHz) δ 9.93 (s, 1H), 9.15 (s, 1H), 8.72−8.51
(m, 4H), 7.81−7.61 (m, 4H), 4.60 (q, J = 7.2 Hz, 2H), 1.55 (t, J = 7.2
Hz, 3H); 13C NMR (CDCl3, 75 MHz) δ 165.7, 146.9, 144.6, 135.3,
131.2, 130.7, 129.7, 128.9, 128.0, 127.8, 127.3, 127.2, 126.6, 124.0,
123.45, 123.36, 123.2, 118.7, 62.0, 14.5; HRMS (ESI-TOF) calcd for
C20H15NO2Na [M + Na]+ 324.0995, found 324.1006.
(2-Azatriphenylen-3-yl)acetonitrile (5aj): Pale yellow solid, mp
176.8−177.7 °C, 23.5 mg (88%); IR (KBr) 3082, 2916, 2851, 2252,
1609, 1399 cm−1; 1H NMR (CDCl3, 300 MHz) δ 9.78 (s, 1H), 8.70−
8.47 (m, 4H), 8.38 (s, 1H), 7.83−7.62 (m, 4H), 4.13 (s, 2H); 13C
NMR (CDCl3, 125 MHz) δ 147.1, 147.0, 136.1, 131.5, 130.0, 129.8,
128.4, 128.0, 127.7, 127.6, 126.9, 123.9, 123.8, 123.5, 122.6, 117.3,
114.6, 26.7; HRMS (ESI-TOF) calcd for C19H12N2Na [M + Na]+
291.0893, found 291.0904.
(2-Azatriphenylen-3-yl)phenylmethanone (5ak): Pale yellow solid,
mp 194.2−194.8 °C, 13.4 mg (40%); IR (KBr) 3060, 2925, 2854,
1652, 1390, 1266 cm−1; 1H NMR (CDCl3, 300 MHz) δ 10.02 (s, 1H),
9.20 (s, 1H), 8.85−8.59 (m, 4H), 8.24−8.14 (m, 2H), 7.87−7.70 (m,
4H), 7.69−7.50 (m, 3H); 13C NMR (CDCl3, 75 MHz) δ 151.6, 145.8,
136.9, 135.7, 132.8, 131.3, 131.1, 130.8, 129.8, 129.0, 128.2, 128.1,
127.9, 127.54, 127.50, 126.3, 124.2, 123.6, 123.5, 123.3, 118.4; HRMS
(ESI-TOF) calcd for C24H15NONa [M + Na]+ 356.1046, found
356.1047.
3-Methyl-2-azatriphenylene (5aa)4: Colorless solid, 14.8 mg
1
(61%); H NMR (CDCl3, 300 MHz) δ 9.81 (s, 1H), 8.77−8.51 (m,
4H), 8.17 (s, 1H), 7.81−7.59 (m, 4H), 2.79 (s, 3H); 13C NMR
(CDCl3, 75 MHz) δ 155.0, 146.2, 135.5, 131.3, 129.4, 129.1, 128.2,
127.7, 127.54, 127.46, 127.3, 123.6, 123.35, 123.31, 122.3, 122.1,
115.1, 24.6; HRMS (ESI-TOF) calcd for C18H14N [M + H]+
244.1121, found 244.1121.
3-Propyl-2-azatriphenylene (5ab): Pale yellow solid, mp 121.0−
122.6 °C, 19.8 mg (73%); IR (KBr) 3076, 2959, 2871, 1725, 1606,
1
1437 cm−1; H NMR (CDCl3, 300 MHz) δ 9.85 (s, 1H), 8.77−8.51
(m, 4H), 8.17 (s, 1H), 7.78−7.58 (m, 4H), 3.01 (t, J = 7.2 Hz, 2H),
1.93 (sext, J = 7.2 Hz, 2H), 1.07 (t, J = 7.2 Hz, 3H); 13C NMR
(CDCl3, 75 MHz) δ 159.0, 146.4, 135.5, 131.3, 129.4, 129.1, 128.3,
127.7, 127.6, 127.5, 127.3, 123.6, 123.35, 123.30, 122.3, 114.6, 40.5,
23.4, 14.0; HRMS (ESI-TOF) calcd for C20H18N [M + H]+ 272.1434,
found 272.1445.
3-Isopropyl-2-azatriphenylene (5ac): Pale yellow solid, mp 116.5−
117.7 °C, 19.3 mg (71%); IR (KBr) 3079, 2954, 2869, 1730, 1604,
1
1437 cm−1; H NMR (CDCl3, 300 MHz) δ 9.88 (s, 1H), 8.74−8.51
(m, 4H), 8.21 (s, 1H), 7.78−7.58 (m, 4H), 3.32 (sept, J = 7.2 Hz, 1H),
1.49 (d, J = 7.2 Hz, 6H); 13C NMR (CDCl3, 75 MHz) δ 164.1, 146.3,
135.6, 131.3, 129.4, 129.0, 128.3, 127.73, 127.71, 127.5, 127.3, 123.6,
123.4, 123.3, 122.4, 122.3, 112.5, 36.4, 22.8; HRMS (ESI-TOF) calcd
for C20H18N [M + H]+ 272.1434, found 272.1440.
1,4-Dimethyl-3-phenyl-2-azatriphenylene (5bd): Pale yellow
3-Phenyl-2-azatriphenylene (5ad)4: Colorless solid, 17.6 mg
solid, mp 188.0−190.0 °C, 17.3 mg (52%); IR (KBr) 3059, 2963,
1
1
2927, 1731, 1542, 1393 m−1; H NMR (CDCl3, 300 MHz) δ 8.67−
(58%); H NMR (CDCl3, 500 MHz) δ 9.90 (d, J = 4.5 Hz, 1H),
8.42 (m, 4H), 7.79−7.38 (m, 9H), 3.21 (s, 3H), 2.82 (s, 3H); 13C
NMR (CDCl3, 75 MHz) δ 155.6, 152.0, 141.5, 139.3, 132.3, 130.9,
129.65, 129.58, 129.5, 129.1, 128.4, 128.3, 127.8, 127.7, 127.2, 126.8,
126.1, 125.8, 123.5, 123.3, 122.6, 28.6, 22.7; HRMS (ESI-TOF) calcd
for C25H20N [M + H]+ 334.1590, found 334.1607.
8.72−8.45 (m, 5H), 8.19 (d, J = 8.0 Hz, 2H), 7.76−7.61 (m, 4H),
7.61−7.54 (m, 2H), 7.51−7.46 (m, 1H); 13C NMR (CDCl3, 125
MHz) δ 154.1, 146.7, 139.6, 135.6, 131.3, 129.7, 129.1, 128.81, 128.78,
128.0, 127.7, 127.6, 127.4, 127.0, 123.5, 123.35, 123.29, 123.1, 122.4,
112.6; HRMS (ESI-TOF) calcd for C23H16N [M + H]+ 306.1277,
found 306.1278.
1,4-Dimethyl-2-azatriphenylene-3-carboxylic Acid Ethyl Ester
(5bi): Colorless oil, 29.8 mg (91%); IR (KBr) 3068, 2978, 2931,
3-(4-Trifluoromethylphenyl)-2-azatriphenylene (5ae): Colorless
1
1718, 1213, 1080 cm−1; H NMR (CDCl3, 300 MHz) δ 8.54 (d, J =
solid, mp 231.8−233.3 °C, 28.4 mg (76%); IR (KBr) 3075, 2933,
1
2364, 1615, 1328, 1111 cm−1; H NMR (CDCl3, 300 MHz) δ 10.04
8.1 Hz, 2H), 8.45 (d, J = 7.5 Hz, 1H), 8.38 (d, J = 8.1 Hz, 1H), 7.79−
7.50 (m, 4H), 4.55 (q, J = 7.2 Hz, 2H), 3.17 (s, 3H), 2.98 (s, 3H), 1.50
(t, J = 7.2 Hz, 3H); 13C NMR (CDCl3, 75 MHz) δ 167.8, 152.4, 145.8,
139.2, 132.2, 131.3, 129.00, 128.98, 128.8, 128.1, 128.0, 127.8, 126.9,
126.3, 124.7, 123.6, 123.4, 61.8, 28.5, 20.8, 14.3; HRMS (ESI-TOF)
calcd for C22H19NO2Na [M + Na]+ 352.1308, found 352.1315.
2-Butyl-1,4-dimethyl-2H-2-azatriphenylen-3-one (7b): Yellow
solid, mp 79.7−82.3 °C, 30.3 mg (92%); IR (KBr) 3062, 2958,
(s, 1H), 8.82 (s, 1H), 8.85−8.57 (m, 4H), 8.33 (d, J = 8.1 Hz, 2H),
7.87−7.65 (m, 6H); 13C NMR (CDCl3, 125 MHz) δ 152.6, 147.0,
142.9, 135.8, 131.5, 130.0, 129.5, 128.2, 128.0, 127.9, 127.6, 127.5,
127.3, 125.79, 125.76, 123.9, 123.63, 123.58, 123.5, 122.7, 113.2;
HRMS (ESI-TOF) calcd for C24H15F3N [M + H]+ 374.1151, found
374.1153.
3-(4-Methoxyphenyl)-2-azatriphenylene (5af): Pale yellow solid,
mp 234.1−235.8 °C, 22.3 mg (66%); IR (KBr) 3069, 3012, 2940,
2842, 1602, 1250 cm−1; 1H NMR (CDCl3, 500 MHz) δ 9.96 (s, 1H),
8.75−8.66 (m, 3H), 8.66−8.56 (m, 2H), 8.17 (d, J = 8.5 Hz, 2H), 7.76
(t, J = 7.5 Hz, 1H), 7.73−7.63 (m, 3H), 7.09 (d, J = 8.5 Hz, 2H), 3.91
(s, 3H); 13C NMR (CDCl3, 125 MHz) δ 160.4, 154.1, 146.7, 135.8,
132.2, 131.4, 129.7, 129.2, 128.3, 127.9, 127.8, 127.7, 127.5, 123.7,
123.5, 123.4, 122.8, 122.5, 114.2, 111.8, 55.4; HRMS (ESI-TOF) calcd
for C24H18NO [M + H]+ 336.1383, found 336.1395.
1
2871, 1622, 1599, 760 cm−1; H NMR (CDCl3, 300 MHz) δ 8.31−
8.08 (m, 3H), 7.77−7.67 (m, 1H), 7.62−7.52 (m, 1H), 7.52−7.34 (m,
3H), 4.31 (t, J = 7.8 Hz, 2H), 2.92 (s, 3H), 2.68 (s, 3H), 1.76 (quint, J
= 7.2 Hz, 2H), 1.51 (sext, J = 7.2 Hz, 2H), 1.02 (t, J = 7.2 Hz, 3H);
13C NMR (CDCl3, 75 MHz) δ 162.2, 140.6, 137.6, 133.3, 130.55,
130.53, 129.9, 129.7, 129.2, 127.8, 126.9, 126.7, 126.2, 123.8, 123.5,
119.6, 113.8, 45.5, 30.7, 20.7, 20.5, 18.0, 13.8; HRMS (ESI-TOF) calcd
for C23H23NONa [M + Na]+ 352.1672, found 352.1673.
4-(2-Azatriphenylen-3-yl)benzonitrile (5ag): Colorless solid, mp
291.2−292.0 °C, 19.3 mg (58%); IR (KBr) 3055, 2923, 2364, 2221,
1604, 1435 cm−1; 1H NMR (CDCl3, 500 MHz) δ 10.03 (s, 1H), 8.82
(s, 1H), 8.80−8.64 (m, 4H), 8.33 (d, J = 8.0 Hz, 2H), 7.89−7.78 (m,
3H), 7.78−7.69 (m, 3H); 13C NMR (CDCl3, 125 MHz) δ 152.0,
147.2, 143.8, 135.9, 132.7, 131.6, 130.2, 129.7, 128.4, 128.1, 127.8,
127.7, 127.53, 127.51, 124.2, 123.7, 123.6, 122.8, 118.9, 113.5, 112.2;
HRMS (ESI-TOF) calcd for C24H15N2 [M + H]+ 331.1230, found
331.1244.
14,14-Dibutyl-14H-indeno[1,2-b]triphenylene (8ak): H8-BINAP
(3.2 mg, 0.0050 mmol) and [Rh(cod)2]BF4 (2.0 mg, 0.0050 mmol)
were dissolved in CH2Cl2, and the mixture was stirred at room
temperature for 10 min. H2 was introduced to the resulting solution in
a Schlenk tube. After stirring at room temperature for 1 h, the resulting
solution was concentrated to dryness. The residue was redissolved in
(CH2Cl)2 (0.4 mL) and a (CH2Cl)2 (0.6 mL) solution of 2k (24.4 mg,
0.100 mmol) was added. A (CH2Cl)2 (1.0 mL) solution of 1a (10.1
mg, 0.050 mmol) was added dropwise to this solution, and the mixture
was stirred at room temperature for 16 h. The resulting solution was
concentrated and purified by a preparative TLC (hexane/CH2Cl2 =
5:6), which furnished adulterated 3ak. Tetrafluoroboric acid diethyl
ether complex (12.3 μL, 0.090 mmol) was added to a stirred solution
of this adulterated 3ak (13.4 mg, 0.030 mmol) in CH2Cl2 (3.0 mL),
and the mixture was stirred at room temperature for 18 h. The
3-Vinyl-2-azatriphenylene (5ah):4: Pale yellow solid, 21.9 mg
(86%);1 H NMR (CDCl3, 500 MHz) δ 9.85 (s, 1H), 8.69−8.63 (m,
1H), 8.62−8.52 (m, 3H), 8.25 (s, 1H), 7.78−7.62 (m, 4H), 7.04 (dd, J
= 17.0, 10.5 Hz, 1H), 6.45 (dd, J = 17.0, 1.0 Hz, 1H), 5.59 (dd, J =
10.5, 1.0 Hz, 1H); 13C NMR (CDCl3, 125 MHz) δ 152.4, 146.7, 136.8,
135.5, 131.3, 129.7, 129.2, 128.2, 127.8, 127.6, 127.4, 123.63, 123.57,
6208
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The Journal of Organic Chemistry
Article
resulting solution was concentrated and purified by a preparative TLC
(hexane/CH2Cl2 = 12:1), which furnished 8ak (13.7 mg, 0.0319
mmol, 64% yield from 1a): Colorless solid, mp 170.0−172.3 °C; IR
ASSOCIATED CONTENT
* Supporting Information
■
S
1
(KBr) 3063, 2958, 2928, 2858, 1458, 1436 cm−1; H NMR (CDCl3,
Detailed conditions for measurement of photophysical proper-
ties, absorption and emission spectra, X-ray crystallographic
500 MHz) δ 8.98 (s, 1H), 8.82 (d, J = 8.0 Hz, 1H), 8.77 (d, J = 8.0 Hz,
1H), 8.72−8.65 (m, 2H), 8.60 (s, 1H), 8.01−7.95 (m, 1H), 7.77−7.63
(m, 4H), 7.46−7.37 (m, 3H), 2.22−2.07 (m, 4H), 1.10 (sext, J = 7.5
Hz, 4H), 0.71−0.62 (m, 10H); 13C NMR (CDCl3, 125 MHz) δ 151.3,
150.0, 140.9, 140.7, 130.3, 129.6, 129.2, 127.7, 127.2, 127.1, 127.0,
126.92, 126.90, 123.4, 123.35, 123.32, 123.1, 120.1, 117.0, 113.8, 55.2,
40.8, 26.1, 23.1, 13.8; HRMS (APCI-TOF) calcd for C33H33 [M + H]+
429.2577, found 429.2573.
1
structures, copies of H and 13C NMR spectra, and X-ray
crystallographic information files. This material is available free
of charge via the Internet at http://pubs.acs.org.
AUTHOR INFORMATION
Corresponding Author
*E-mail: tanaka-k@cc.tuat.ac.jp.
■
Triphenylene-Based Ladder Molecule 8al. H8-BINAP (6.3 mg,
0.010 mmol) and [Rh(cod)2]BF4 (4.1 mg, 0.010 mmol) were
dissolved in CH2Cl2, and the mixture was stirred at room temperature
for 10 min. H2 was introduced to the resulting solution in a Schlenk
tube. After stirring at room temperature for 1 h, the resulting solution
was concentrated to dryness. The residue was redissolved in (CH2Cl)2
(0.4 mL), and a (CH2Cl)2 (0.6 mL) solution of 2l (20.5 mg, 0.0500
mmol) was added. A (CH2Cl)2 (1.0 mL) solution of 1a (50.6 mg,
0.250 mmol) was added dropwise to this solution, and the mixture was
stirred at room temperature for 16 h. The resulting solution was
concentrated and purified by a preparative TLC (hexane/CH2Cl2 =
35:90), which furnished adulterated 3al. Tetrafluoroboric acid diethyl
ether complex (26.3 μL, 0.193 mmol) was added to a stirred solution
of this adulterated 3al in CH2Cl2 (3 mL), and the mixture was stirred
at room temperature for 13 h. The reaction was quenched by the
addition of water and extracted with CH2Cl2. The organic layer was
washed with H2O and brine, dried over Na2SO4, and concentrated.
The residue was purified by a silica gel column chromatography
(hexane/CH2Cl2 = 5:1) to give 8al (27.8 mg, 0.0357 mmol, 71% yield
from 2l): Colorless solid, mp >300 °C; IR (KBr) 3080, 2953, 2927,
2858, 1723, 1421 cm−1; 1H NMR (CDCl3, 300 MHz) δ 9.09 (s, 2H),
8.93 (d, J = 7.5 Hz, 2H), 8.81 (d, J = 7.5 Hz, 2H), 8.71 (d, J = 7.5 Hz,
4H), 8.65 (s, 2H), 7.99 (s, 2H), 7.83−7.58 (m, 8H), 2.44−2.09 (m,
8H), 1.30−1.01 (m, 8H), 0.90−0.64 (m, 8H), 0.66 (t, J = 7.2 Hz,
12H); 13C NMR (CDCl3, 125 MHz) δ 151.0, 150.5, 141.2, 140.9,
130.34, 130.32, 129.8, 129.6, 129.3, 129.2, 127.2, 127.1, 126.93,
126.89, 123.5, 123.4, 123.3, 117.1, 114.5, 113.7, 55.0, 41.3, 26.2, 23.2,
13.9; HRMS (APCI-TOF) calcd for C60H59 [M + H]+ 779.4611,
found 779.4608.
Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
■
This work was supported partly by a Grant-in-Aid for Scientific
Research (No. 20675002) from MEXT and ACT-C from JST
(Japan). We thank Takasago International Corporation for the
gift of H8-BINAP, and Umicore for generous support in
supplying a rhodium complex.
REFERENCES
■
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Triphenylene-Based Ladder Molecule 8am. H8-BINAP (6.3 mg,
0.010 mmol) and [Rh(cod)2]BF4 (4.1 mg, 0.010 mmol) were
dissolved in CH2Cl2, and the mixture was stirred at room temperature
for 10 min. H2 was introduced to the resulting solution in a Schlenk
tube. After being stirred at room temperature for 1 h, the resulting
solution was concentrated to dryness. The residue was redissolved in
(CH2Cl)2 (0.4 mL), and a (CH2Cl)2 (0.6 mL) solution of 2m (33.4
mg, 0.0500 mmol) was added. A (CH2Cl)2 (1.0 mL) solution of 1a
(50.6 mg, 0.250 mmol) was added dropwise to this solution, and the
mixture was stirred at room temperature for 16 h. The resulting
solution was concentrated and purified by a preparative TLC (hexane/
CH2Cl2 = 1:2), which furnished 3am. Tetrafluoroboric acid diethyl
ether complex (30.0 μL, 0.220 mmol) was added to a stirred solution
of this adulterated 3am in CH2Cl2 (5 mL), and the mixture was stirred
at room temperature for 13 h. The reaction was quenched by the
addition of water and extracted with CH2Cl2. The organic layer was
washed with H2O and brine, dried over Na2SO4, and concentrated.
The residue was purified by a preparative TLC (hexane/CH2Cl2 =
10:1) to give 8am (34.0 mg, 0.0329 mmol, 66% yield from 2m):
Yellow solid, mp 122.4−124.5 °C; IR (KBr) 3077, 2925, 2852, 1609,
Chem.Asian J. 2009, 4, 508. (h) Varela, J. A.; Saa,
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Hoboken, NJ, 2007; Vol. 68, p 1. (l) Chopade, P. R.; Louie, J. Adv.
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1
1421, 1289 cm−1; H NMR (CDCl3, 500 MHz) δ 9.10 (s, 2H), 8.94
(d, J = 8.0 Hz, 2H), 8.81 (d, J = 7.0 Hz, 2H), 8.75 (s, 2H), 8.71 (d, J =
8.0 Hz, 4H), 7.99 (s, 2H), 7.97 (s, 2H), 7.80−7.65 (m, 8H), 2.38−2.19
(m, 4H), 1.81 (s, 12H), 1.29−1.04 (m, 36H), 0.94−0.83 (m, 4H), 0.79
(t, J = 6.5 Hz, 6H); 13C NMR (CDCl3, 75 MHz) δ 153.7, 153.4, 151.0,
141.5, 139.4, 138.1, 130.2, 129.6, 129.4, 129.1, 127.1, 126.9, 126.8,
123.5, 123.4, 123.3, 117.0, 114.7, 113.8, 54.7, 46.7, 41.2, 31.8, 30.2,
29.7, 29.60, 29.55, 29.3, 29.2, 28.1, 23.9, 22.6, 14.0; HRMS (ESI-TOF)
calcd for C79H87 [M + H]+ 1035.6802, found 1035.6766.
(9) For other examples of the transition-metal-catalyzed [2 + 2 + 2]
cycloaddition of 1,7-octadiyne derivatives with alkynes (nickel
catalyses), see the following: (a) Jeevanandam, A.; Korivi, R. P.;
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Article
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(11) For selected other recent examples of the transition-metal-
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nitriles, see the following. Co: (a) Hapke, M.; Weding, N.;
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(16) The double [2 + 2 + 2] cycloaddition of 1a with terminal diyne
2k proceeded in the presence of the cationic rhodium(I)/H8-BINAP
catalyst at room temperature to give the known benzene-linked bis-
triphenylene 3an. For a report of 3an, see: Yu, J.-Y.; Huang, M.-J.;
Chen, C.-H.; Lin, C.-S.; Cheng, C.-H. J. Phys. Chem. C. 2009, 113,
7405. The double [2 + 2 + 2] cycloaddition of 1a with dinitrile 4g also
proceeded in the presence of the cationic rhodium(I)/BINAP catalyst
at room temperature to give benzene-linked bis-azatriphenylene 5ag′.
Unfortunately, these cycloadducts could not be fully characterized due
to their insolubility in common organic solvents.
(17) The reaction of the terminal diyne 1a with n-butylisocyanate 6
was also examined in the presence of the cationic rhodium(I)/H8-
BINAP catalyst at room temperature. The desired azatriphenylene 7a
was generated with high yield, while this cycloadduct could not be
isolated in a pure form due to its instability.
(18) The fluorescence quantum yield for triphenylene is 6.6%. See:
Montalti, M.; Credi, A.; Prodi, L.; Gandolfi, M. T. Handbook of
Photochemistry, 3rd ed; Taylor & Francis: Boca Raton, FL, 2006.
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