A convenient synthesis of Benzo[c]naphtho[2,1-p]chrysene

Full text of DOI:10.1021/jo961045e

7
198
J . Org. Chem. 1996, 61, 7198-7199
A Con ven ien t Syn th esis of
Sch em e 1
Ben zo[c]n a p h th o[2,1-p]ch r ysen e
Stefan Hagen and Lawrence T. Scott*
Department of Chemistry, Merkert Chemistry Center, Boston
College, Chestnut Hill, Massachusetts 02167-3860
Received J une 3, 1996
The polycyclic aromatic hydrocarbon (PAH) benzo[c]-
naphtho[2,1-p]chrysene1 (1) has recently attracted re-
newed attention as a potential precursor for the synthesis
of bowl-shaped fullerene substructures.2 The published
synthetic approaches to 1, however, are lengthy and
entail one or more photocyclizations of stilbene-type
compounds that suffer from competing [2 + 2]cycloaddi-
tion reactions at normal concentrations and are thereby
rendered quite inefficient.2
bc,3,4
We report here a conve-
nient four-step synthesis of 1 that can be performed on
a multigram scale starting from the commercially avail-
able R-tetralone (2) and 2-bromonaphthalene.
By a method similar to that of Eisenbraun et al.,5 the
aldol condensation of 2 with TiCl
c
and thereby poorly suited for variable temperature NMR
studies, the free enthalpy of activation for signal coales-
4
in refluxing 1,2-
dichloroethane (DCE) gives the dimeric ketone 3 in 71%
q
cence (∆G ) 20.0 ( 0.2 kcal/mol) was determined by
c
5
a-c
13
yield (Scheme 1).
In contrast to the condensation of
C-NMR spectroscopy (125.7 MHz, DMSO-d ), an aver-
6
6
6
-methoxy-R-tetralone with TiCl
4
, no products arising
age value being taken from the coalescence of three
different signals.9 No attempt was made to separate 6a
and 6b, since a rotational barrier of 20 kcal/mol is
insufficient to prevent complete reequilibration of the
individual conformers within a few minutes at room
temperature.10
from the connection of three molecules of 2 were observed
even at these elevated temperatures. The reaction of 3
with 2-naphthyl lithium (4) in THF at -70 °C produces
the desired tertiary alcohol 5 (70%), which can be
aromatized to 1,2′:1′,2′′-ternaphthalene (6) in high yield
(94%) by treatment with 2,3-dichloro-5,6-dicyano-1,4-
benzoquinone (DDQ) and a catalytic amount of p-tolu-
7
enesulfonic acid (p-TsOH) in refluxing benzene.
1
By H-NMR spectroscopy, 6 was shown to consist of a
nearly 1:1 mixture of two conformers at room tempera-
8
ture (6a and 6b) with significant barriers to rotation
around the aryl-aryl bonds hindering their interconver-
1
sion. Since the H-NMR spectrum is badly overlapping,
(1) The name benzo[c]naphtho[2,1-p]chrysene is in accord with the
nomenclature for PAH recommended by the IUPAC and applied by
Chemical Abstracts. The more common name in the chemical literature
for compound 1 is tribenzo[c,i,o]triphenylene.
(2) (a) Faust, R.; Vollhardt, K. P. C. 7th International Symposium
of Novel Aromatics, Victoria, B.C., Canada, 1992; Poster 61. (b) Mehta,
G.; Raghava Sharma, G. V.; Krishna Kumar, M. A.; Vedavyasa, T. V.;
J emmis, E. D. J . Chem. Soc., Perkin Trans. 1 1995, 2529. (c) Erickson,
M. S.; Milliken, J . Polycyclic Arom. Compd. 1996, 8, 1. (d) The
successful conversion of 1 to benz[5,6]-as-indaceno[3,2,1,8,7-mnopqr]-
indeno[4,3,2,1-cdef]chrysene has been presented: Hagen, S.; Bratcher,
M. S.; Scott, L. T.; Zimmermann, G. 210th ACS National Meeting, New
Orleans, 1996; Organic Division poster 52.
Photocyclization of 6 in benzene by the method of Katz
et al.,11 with iodine and propylene oxide, results in the
formation of 1 (96%). Benzo[b]naphtho[2,1-p]chrysene
(7), the other possible product of photocyclization, could
not be detected. The high site selectivity of this photo-
chemical reaction is in accord with the calculated sums
(
3) Laarhoven, W. H.; van Broekhoven, J . A. M. Tetrahedron Lett.
970, 1, 73.
4) (a) J uriew, J .; Skorochodowa, T.; Merkuschew, J .; Winter, W.;
Meier, H. Angew. Chem. 1981, 93, 285; Angew. Chem., Int. Ed. Engl.
981, 20, 269. (b) Winter, W.; Langjahr, U.; Meier, H.; Merkuschew,
J .; J uriew, J . Chem. Ber. 1984, 117, 2452. (c) Meier, H. Angew. Chem.
992, 104, 1425; Angew. Chem., Int. Ed. Engl. 1992, 31, 1399.
5) For prior synthesis of 3 see: (a) Orchin, M.; Reggel, L.; Friedel,
of the free valencies in the S
centers that are to be linked (F
rs* is greater than 1.0 for the formation of 1 and lower
than 1.0 for the unobserved formation of 7 (Scheme 2).
1
state (Frs*) for the carbon
1
4
c,12
r
s
*, F *). As required,
(
F
1
1
(
(9) Signals at δ ) 138.46 ppm (∆ν ) 18.9 Hz, T
136.23 ppm (∆ν ) 23.5 Hz, T ) 120(2 °C), δ ) 135.41 ppm (∆ν )
33.7 Hz, T
c
) 117(2 °C), δ )
R. A. J . Am. Chem. Soc. 1949, 71, 2743. (b) Burnham, J . W.; Melton,
R. G.; Eisenbraun, E. J .; Keen, G. W.; Hamming, M. C. J . Org. Chem.
c
c
) 120(2 °C); δ given for fast exchange at 160 °C; ∆ν given
1
973, 38, 2783. (c) Holba, A. G.; Premasager, V., Barot, R. C.,
for slow exchange at 25 °C.
Eisenbraun, E. J . Tetrahedron Lett. 1984, 26, 571.
(10) (a) House, H. O.; Koepsell, D. G.; Campbell, W. J . J . Org. Chem.
1972, 37, 1003. (b) Ibuki, E.; Ozasa, S.; Fujioka, Y.; Mizutani, H. Bull.
Chem. Soc. J pn. 1982, 55, 845.
(11) Liu, L.; Yang, B.; Katz, T. J .; Poindexter, M. K. J . Org. Chem.
1991, 56, 3769.
(
6) Pyrko, A. N. Zh. Org. Khim. 1992, 28, 215.
(7) This work was originally inspired by the publication of Burnham
et al.5 In the present case, however, their approach did not result in
b
1
but gave instead its constitutional isomer naphtho[2,1-s]picene and
the PAH phenanthro[1,2,3,4-ghi]perylene. These findings are still
under investigation and will be published elsewhere.
(12) (a) Scholz, M.; Dietz, F.; Muehlstaedt, M. Z. Chem. 1967, 7,
329. (b) Scholz, M.; Dietz, F.; Muehlstaedt, M. Tetrahedron Lett. 1967,
665. (c) Laarhoven, W. H.; Cuppen, T. H. J . M.; Nivard, R. J . F. Recl.
Trav. Chim. Pays-Bas 1968, 87, 687.
(
8) The calculated differences in the heats of formation of 6a and
6
b are 0.019 kcal/mol (PM3) and 0.042 kcal/mol (AM1).
S0022-3263(96)01045-6 CCC: $12.00 © 1996 American Chemical Society

Notes
J . Org. Chem., Vol. 61, No. 20, 1996 7199
Sch em e 2
solution. After the addition of 100 mL of diethyl ether, the
organic phase was washed with water, dried with MgSO , and
4
filtered. After evaporation of the solvent under reduced pres-
sure, the residue was dissolved in boiling n-hexane and allowed
to crystallize overnight, yielding colorless crystals of 5 (5.973 g,
7
0%, mp ) 136.5-136.8 °C). IR (KBr): ν 3427 cm- (OH). H-
1
1
NMR: δ 7.63-7.56 (m, 3H), 7.51 (d, J ) 8.5 Hz, 1H), 7.35-7.31
(
(
(
m, 2H), 7.26-7.21 (m, 2H), 7.17 (d, J ) 8.6 Hz, 1H), 7.11-7.09
m, 2H), 6.81 (d, J ) 7.0 Hz, 1H), 6.74-6.68 (m, 2H), 6.62-6.59
m, 1H), 6.14 (m, 1H), 3.68 (d, J ) 10.4, 1H), 3.17 (s, 1H), 3.13-
3
.03 (m, 2H), 2.62-2.58 (m, 2H), 2.33-2.24 (m, 2H), 2.17-2.08
13
(m, 1H), 2.00-1.93 (m, 1H).
C-NMR: δ ) 145.42, 142.25,
1
1
1
2
4
37.58, 137.31, 136.33, 134.78, 132.63, 132.39, 130.46, 128.72,
28.08, 127.68, 127.36 (2 C), 127.20, 127.07, 126.65, 126.19,
25.77 (2 C), 125.71, 125.65, 125.57, 122.38, 76.31, 47.55, 29.92,
8.91, 25.32, 23.47. HRMS:
02.1987. Anal. Calcd for C30
C
30
H
26O calcd 402.1984, found
H
26O: C, 89.51; H, 6.51. Found:
C, 89.37; H, 6.39.
1
,2′:1′,2′′-Ter n a p h th a len e (6). To a stirred solution of
alcohol 5 (6.25 g, 15.5 mmol) in 600 mL of benzene was added
DDQ (13.6 g, 60 mmol) in one portion, and the solution was
heated under reflux with stirring for 1.5 h. Then 100 mg of
p-TsOH was added, and the reaction mixture was stirred for
another 2 h under reflux. After the mixture was cooled to room
temperature, the organic phase was extracted with 5% NaOH
solution until the aqueous phase remained colorless, washed
The fact that only extraction or recrystallization is
necessary to obtain analytically pure samples in each of
the four steps emphasizes the convenience of this syn-
thesis.
4 4
with saturated NH Cl solution and water, dried with MgSO ,
and filtered. Evaporation of the solvent under reduced pressure,
treatment with refluxing methanol, and filtration yielded 5.30
g (90%) of colorless crystals of 6 (mixture of isomers, mp )
1
0
61.5-162.5 °C). From the filtrate was crystallized additionally
.27 g (4.5%) of 6. UV (CH CN): λmax(log ꢀ) 220 nm (5.135), 272
3
1
Exp er im en ta l Section
(4.342, sh), 284 (4.390). H-NMR (25 ˚C, two conformers): δ
.97-7.93 (m, 4H), 7.81 (s, 1H), 7.74-7.67 (m, 8H), 7.62-7.48
m, 8H), 7.45 (d, J ) 8.4 Hz, 1H), 7.39-7.28 (m, 12H), 7.23-
7
(
Gen er a l P r oced u r es. 1H-NMR (400 MHz) and 13C-NMR
(100 MHz) spectra were recorded in CDCl
3
with CDCl
3
(δ ) 7.26
13
7
.12 (m, 5H), 7.01 (d, J ) 8.4 Hz, 1H). C-NMR (125.7 MHz,
DMSO-d , 160 °C, δ 39.51 ppm as internal standard): δ 138.46,
37.73, 136.23, 135.41, 132.33, 132.18, 131.90, 131.74, 131.32,
31.11, further signals at 129.2-123.0 (no complete coalescence).
and 77.23 ppm, respectively) or TMS (δ ) 0.00 ppm) as internal
standard unless otherwise noted. Melting points are uncor-
rected.
6
1
1
3
,3′,4,4′-Tetr a h yd r o-[1,2′-bin a p h th a len ]-1′(2′H)-on e (3).
To a stirred solution of R-tetralone (2, 10.0 g, 68.5 mmol) in 50
mL of 1,2-dichloroethane at 25 °C under N was added 5.00 mL
of TiCl (45.5 mmol) all at once. The dark brownish reaction
MS (70 eV): m/ z (rel int) 381 (32), 380 (100), 379 (31), 377 (14),
76 (13), 253 (13), 252 (20). HRMS: C30 20 calcd 380.1565,
20: C, 94.70; H, 5.30.
3
H
2
found 380.1560. Anal. Calcd for C30
Found: C, 94.77; H, 5.27.
H
4
mixture was heated under reflux for 30 min, cooled, and poured
into ice-cooled 2 M HCl. The organic phase was washed with 1
M HCl and water, dried with MgSO , and filtered. The solvent
4
Ben zo[c]n a p h th o[2,1-p]ch r ysen e (1). A stirred solution of
hydrocarbon 6 (4.74 g, 12.5 mmol), iodine (3.30 g, 13 mmol), and
propylene oxide (40 mL, 570 mmol) in 550 mL of benzene in a
was removed under reduced pressure, and the crude product was
extracted with hot pentane yielding 6.675 g (71%) of pale yellow
quartz flask purged with N
2
was irradiated with a 450 W
medium-pressure mercury UV-lamp for 21 h. After evaporation
of the solvent under reduced pressure and recrystallization of
the crude product from benzene/hexane, the mother liquor was
irradiated for another 3 h and worked up in the same manner,
5
a
crystals of 3 (mp 130.5-132 °C (lit. mp 132.5-134.2 °C); IR,
1
UV, H-NMR, and MS were in agreement with those reported
5
b,c
13
in the literature ). C-NMR: δ 199.08, 144.12, 136.97, 135.32,
1
1
33.83, 133.48, 133.01, 128.84, 127.86, 127.62, 127.18, 126.83,
26.76, 126.33, 123.17, 50.83, 28.77, 28.30, 28.15, 23.20.
3
yielding a total of 4.52 g (96%) of 1 (mp ) 231-232 °C (lit. mp
1
13
2
33-234 °C); MS, UV, H-NMR, and C-NMR were in agree-
2c,3,4b
3
,4,3′,4′-Tetr a h yd r o-[1,2′:1′,2′′-ter n a p h th a len ]-1′(2′H)-ol
5). To a stirred solution of 2-bromonaphthalene (5.657 g, 27.3
mmol) in 400 mL of THF at -70 °C were added 12.3 mL of 2.5
M n-butyllithium in hexane (31 mmol) under N After the
ment with those reported in the literature
).
(
.
Ack n ow led gm en t. Financial support of this work
by the U.S. Department of Energy and by a scholarship
to S.H. from the German Academic Exchange Service
is gratefully acknowledged.
2
yellow solution had been stirred for 1 h (glass stirrer), a solution
of ketone 3 (5.821 g, 21.2 mmol) in 100 mL of THF was added
dropwise. The reaction mixture was stirred for another 1 h at
-
70 °C, allowed to warm to room temperature over a period of
2
h, stirred for 1 h more, and then quenched with NH Cl
4
J O961045E