Carbon networks based on 1,5-naphthalene units. Synthesis of 1,5-naphthalene nanostructures with extended π-conjugation

Article abstract of DOI:10.1021/jo0203589

The synthesis and spectroscopic characterization of nanometer-sized conjugated molecules of 5-X-naphthylethynyl (X= NO₂, NMe₂) units with precise length and constitution have been carried out. A new extended π-conjugated 5-nitronaphthyl family was synthesized by palladium-catalyzed cross-coupling reaction between the protected 5-iodonaphthylethynyl 5a and 1-ethynyl-5-nitronaphthalene 9, or the resulting ethynyl compound 11 and the 1-iodo-5-nitronaphthalene 3. Catalytic oxidative dimerization of the terminal acetylene compounds permits the isolation of the corresponding 1,3-butadiyne derivatives 16-18, with the nitro groups at the ends of the conjugation, in excellent yields. A new family of conjugated 5-nitro-(naphthylethynyl)-[5-(N,N-dimethylamino)]-naphthalene (20-22), was also synthesized by palladium-catalyzed cross-coupling reaction between 5-iodo-N,N-dimethylnaphthalene-1-amine (19) with the appropriate terminal acetylene (9, 11, and 13 respectively). Compounds 20-22 show a fluorescence emission and also exhibit a charge-transfer absorption in the visible spectrum. X-ray structure of 20 confirms a centrosymmetric dimer association with an interplanar distance of 3.43 A, and the naphthalene rings adopt an anti conformation around the C≡C triple bond.

Full text of DOI:10.1021/jo0203589

Ca r bon Netw or k s Ba sed on 1,5-Na p h th a len e Un its. Syn th esis of
1,5-Na p h th a len e Na n ostr u ctu r es w ith Exten d ed π-Con ju ga tion
J . Gonzalo Rodr´ıguez* and J . Luis Tejedor
Departamento de Quı´mica Orga´nica, Facultad de Ciencias, Universidad Auto´noma,
Cantoblanco, 28049-Madrid, Spain
gonzalo.rodriguez@uam.es
Received May 31, 2002
The synthesis and spectroscopic characterization of nanometer-sized conjugated molecules of 5-X-
naphthylethynyl (X) NO2, NMe2) units with precise length and constitution have been carried
out. A new extended π-conjugated 5-nitronaphthyl family was synthesized by palladium-catalyzed
cross-coupling reaction between the protected 5-iodonaphthylethynyl 5a and 1-ethynyl-5-nitronaph-
thalene 9, or the resulting ethynyl compound 11 and the 1-iodo-5-nitronaphthalene 3. Catalytic
oxidative dimerization of the terminal acetylene compounds permits the isolation of the corre-
sponding 1,3-butadiyne derivatives 16-18, with the nitro groups at the ends of the conjugation, in
excellent yields. A new family of conjugated 5-nitro-(naphthylethynyl)-[5-(N,N-dimethylamino)]-
naphthalene (20-22), was also synthesized by palladium-catalyzed cross-coupling reaction between
5-iodo-N,N-dimethylnaphthalene-1-amine (19) with the appropriate terminal acetylene (9, 11, and
13 respectively). Compounds 20-22 show a fluorescence emission and also exhibit a charge-transfer
absorption in the visible spectrum. X-ray structure of 20 confirms a centrosymmetric dimer
association with an interplanar distance of 3.43 Å, and the naphthalene rings adopt an anti
conformation around the CtC triple bond.
In tr od u ction
attention by the electronic and optical properties of poly-
(1,3-diynes).13
The synthesis and characterization of nanometer-sized
conjugated molecules of precise length and constitution
are of widespread interest, which is due to their inherent
synthetic flexibility which permits the design of molec-
ular architectures with important properties.1,2 Molecules
showing extended π-conjugation, in general, exhibit high
thermal stability and can present electroconductive,
magnetic, and optical properties.3
The naphthalene conjugated system, for example, the
1,4-ethynylnaphthalene unit, has been used in binaph-
thyl-based oligomers,14 as a spacer in phenylene or
diporphyrin connectors, and applied to studies of in-
tramolecular energy transfer.15,16 However, the 1,5-di-
(4) Nanostructure Based on Molecular Materials; Go¨pel, W.; Ziegler,
Ch., Eds.; VCH: Weinheim, Germany, 1992.
In particular, the field of molecular electronics involves
the search for new materials that favor long-range
vectorial electron or energy transfer and/or exhibit
nonlinear optical properties.4-6 A variety of potential
applications, such as artificial photosynthesis,7 photoca-
talysis,8 molecular photovoltaic cells,9 molecular infor-
matics,10 and optoelectronic devices,11,12 are beginning to
emerge from this new field of research.
(5) Inorganic Materials; Bruce, D. W., O’Hare, D., Eds.; J . Wiley &
Sons Ltd: Chichester, England, 1992.
(6) (a) Verhoeven, J . W.; Kroon, J .; Paddon-Row: M. N.; Warman,
J . M. In Supramolecular Chemistry; Balzani, V., De Cola, L., Eds.;
NATO ASI Ser. C, 1992; Vol. 371, p 181. (b) Balzani, V.; Sacandola, F.
In Supramolecular Photochemistry; Harwood: Chichester, 1991.
(7) Gust, D.; Moore, T. A. Science 1989, 244, 35.
(8) Ziessel, R. In Photosensitization and Photocatalysis Using Inor-
ganic and Organometallic Compounds; Kalyanasundaram, K., Gra¨tzel,
M., Eds.; Kluwer Academic Publishers: Dordecht, 1993; p 217.
(9) O’Regan, B.; Gra¨tzel, M. Nature 1991, 353, 737.
Solid-state polymerization of some 1,3-diynes to form
crystalline conjugated poly(en-ynes) has attracted much
(10) Reynolds, J . R. J . Mol. Electron. 1986, 2, 1.
(11) Grubbs, R. H.; Gorman, C. B.; Ginsburg, E. J .; Perry, J . W.;
Marder, S. R. In Materials with Nonlinear Optics, Chemical Perspec-
tives; Marder, S. R., Sohn, J . E., Stricky, G. D., Eds.; ACS Symposium
Series, 1991; p 455.
(1) Tour, J . M. Chem. Rev. 1996, 96, 537.
(2) (a) Shenlin Huang, S.; Tour, J . M. Polym. Prepr. 1998, 39(2),
525-526. (b) Grosshenny, V.; Romero, F. M.; Ziessel, R. J . Org. Chem.
1997, 62, 1491. (d) Brad Wan, W.; Brand, S. C.; Park; J . J .; Haley, M.
M. Chem. Eur. J . 2000, 6, 2044.
(3) (a) Conjugated Polymers and Related Materials: The Intercon-
nection of Chemical and Electronic Structure; Salaneck, W. R., Lund-
stro¨m, I., Ranby, B., Eds.; Oxford University Press: Oxford, 1993. (b)
Photonic and Optoelectronic Polymers; J enekhe, S. A., Wynne, K. J .,
Eds.; American Chemical Society: Washington D. C., 1995. (c)
Nonlinear Optics of Organic Molecules and Polymers; Nalwa, H. S.,
Miyata, S. Eds.; CRC Press: Boca Raton, FL, 1997. (d) Electronic
Materials: The Oligomer Approach; Mu¨llen, K., Wegner, G., Eds.;
Wiley-VCH: Weinheim, 1998.
(12) Barker, J . R. In Molecular Electronics; Petty, M. C., Bryce, M.
R., Bloor, D., Eds.; Edward Arnold: London, 1995; p 345.
(13) Polydiacetylenes; Bloor, D., Chance, R. R., Eds.; NATO ASI
series E, No. 102, Matinus Nijkoff, Boston, 1985. A. E. Stiegman, E.
Graham, K. J . Perry, R. Khundkard, L. T. Cheng and J . W. Perry, J .
Am. Chem. Soc. 1991, 113, 1658, and references therein.
(14) Chow, H.; Ng, M. Tetrahedron: Asymmetry 1996, 7(8), 2251-
2262. Ibid. Tetrahedron Lett. 1996, 37(17), 2979-2982.
(15) El-Ghayoury, A.; Harriman, A.; Khatyr, A.; Ziessel, R. Tetra-
hedron Lett. 1997, 38(14), 2471-2474. El-Ghayoury, A.; Harriman, A.;
Khatyr, A.; Ziessel, R. J . Phys. Chem. A 2000, 104(7), 1512-1523. Ibid.
Angew. Chem., Int. Ed. 2000, 39(1), 185-189.
10.1021/jo0203589 CCC: $22.00 © 2002 American Chemical Society
Published on Web 10/04/2002
J . Org. Chem. 2002, 67, 7631-7640
7631

Rodr´ıguez and Tejedor
SCHEME 1 a
SCHEME 2 a
a
Reagents: i, Na2S, NH4OH; at 80 °C; ii. NaNO2, H2SO4; KI.
a
Reagents: i, 2-methylbut-3-yn-2-ol, PdCl2(PPh3)2, Cu2Cl2,
HNEt2; ii. NaOH, toluene, at reflux temperature.
ethynylnaphthalene unit has been less used, although it
has been integrated into di- and trinuclear alkyne-
rhodium(I) complexes.17
SCHEME 3 a
The synthesis and the structure analysis of the novel
rigid conjugate nanostructures based on 1,5-diethynyl-
naphthalene units are now reported.
Discu ssion
a
Reagents: i, 2-methylbut-3-yn-2-ol, PdCl2(PPh3)2, Cu2Cl2,
NEt3; ii. NaOH, toluene, at reflux temperature.
The construction of 1,5-naphthalene conjugated nano-
structures has been undertaken from ethynylnaphtha-
lene units. These were prepared by a multistep process
from iodonaphthalene derivatives which were prepared
starting from 1,5-dinitronaphthalene by reduction with
sodium sulfide in a concentrated aqueous ammonia
solution, giving 5-nitronaphthalen-1-amine (1) and 1,5-
diaminonaphthalene (2).18 Compounds 1 and 2 were
transformed into 1-iodo-5-nitronaphthalene (3) and 1,5-
diiodonaphthalene (4) through the single or double dia-
zonium salt, respectively, with potassium iodide, Scheme
1.19,20
The diiodo compound 4 was transformed into a mixture
of 4-(5-iodo-1-naphthyl)-2-methylbut-3-yn-2-ol (5a ) and
1,5-di-[4-(2-methylbut-3-yn-2-ol)]-naphthalene (5b) by
cross-coupling with 2-methylbut-3-yn-2-ol, catalyzed by
palladium. Both derivatives 5a and 5b were individually
transformed to the respective acetylenes 6 and 7 by
treatment with powdered sodium hydroxide, in toluene
at reflux temperature,21 Scheme 2. However, for com-
pound 5a was also isolated an insoluble black powder
(10%), that by IR and mass spectroscopy shows the
naphthylethynyl moiety and proceeds by the nucleophilic
substitution of the iodo by the sodium acetylide during
the acetone elimination step. This secondary product
diminishes under diluted conditions.
transformed into 1-ethynyl-5-nitronaphthalene (9) by
treatment with powdered sodium hydroxide in refluxing
toluene,21 Scheme 3.
The 1-ethynyl-5-nitronaphthalene and its iodo deriva-
tive precursor serve as precursors to nanostructures with
an electron-withdrawing nitro group at the end of the
conjugated system.
Mon on itr oa r yl Na n ostr u ctu r es: 1-Eth yn yl-5-[(5-
n itr o-1-n a p h th yl)eth yn yl]n a p h th a len e a n d 1-Eth y-
n yl-5-({5-[(5-n itr o-1-n a p h th yl)eth yn yl]-1-n a p h th yl}-
eth yn yl)n aph th alen e (11 an d 13). Following the general
method discussed in Scheme 2 for the preparation of
5a ,b, the cross-coupling reaction, catalyzed by palladium,
between compounds 9 and 5a , yields 2-methyl-4-{5-[(5-
nitro-1-naphthyl)ethynyl]-1-naphthyl}but-3-yn-2-ol (10)
as a yellow solid, in good yield (64%). The treatment of
10 with powdered sodium hydroxide in dry toluene at
reflux temperature21 gives 1-ethynyl-5-[(5-nitro-1-naph-
thyl)ethynyl]naphthalene (11) as a yellow-brown solid in
practically quantitative yield.
A DSC analysis of 11 was carried out. The diagram
exhibits an endothermic peak corresponding with the
melting of the compound at 205.3 °C after which appears
a broad exothermic peak of decomposition. In the IR
spectrum, the black solid resulting from the thermal
treatment shows a band at 2193 cm-1 corresponding to
CtC stretching vibration. By 1H NMR were observed
groups of signals corresponding to the decomposition
products, but also a group of broad signals in the
aromatic region with frequencies related to the monomer,
which were assigned to a polymer of 11.
In a similar way, 5-nitronaphthalen-1-amine (1) was
transformed through the diazonium salt and potassium
iodide in the iodo derivative 3, Scheme 1, which by
heterocoupling with 2-methylbut-3-yn-2-ol, catalyzed by
palladium, gives the nitroethynyl alcohol 8, which was
(16) Kajanus, J .; Van Berlekom, S.; Albinsson, B.; Martensson, J .
Synthesis 1999, 7, 1155-1162.
(17) Werner, H.; Bachmann, P.; Laubender, M.; Gevert, O. Eur. J .
Inorg. Chem. 1970, 9, 1217-1224.
A new structure 13 was synthesized, increasing 11 by
a 5-naphthylethynyl unit. Thus, by cross-coupling be-
tween 5a and 11, catalyzed by palladium, was isolated
2-m et h yl-4-[5-({5-[(5-n it r o-1-n a ph t h yl)et h yn yl]-1-
naphthyl}ethynyl)-1-naphthyl]but-3-yn-2-ol (12), as a
brown solid in moderate yield (50%). The treatment of
12 with sodium hydroxide in refluxing toluene21 gives
(18) Harthan, W. W.; Silloway, H. L. Organic Syntheses; Wiley: New
York, 1955; Collect. Vol. III, p 82.
(19) Bossenbroek, B.; Sanders, D. C.; Curry, H. M.; Shechter, H. J .
Am. Chem. Soc. 1969, 9, 371.
(20) Hodgson, H. H.; Whitehurst, J . S. J . Chem. Soc. 1947, 80.
(21) Ames, D. E.; Bull, D.; Takundwa, C. Synthesis 1981, 384.
Rodriguez, J . G., Mart´ın-Villamil, R., Cano, F. H., and Fonseca, I., J .
Chem. Soc., Perkin Trans. 1 1997, 709-714.
7632 J . Org. Chem., Vol. 67, No. 22, 2002

Carbon Networks Based on 1,5-Naphthalene Units
SCHEME 4 a
a
Reagents: i. PdCl2(PPh3)2, Cu2Cl2, NEt3; ii. NaOH, toluene, at reflux temperature.
lene (16)22 and naphthylethynyl homologues 17 and 18
were prepared to explore the solubility of the new
compounds and the nitro electron-withdrawing effect on
the conjugation and also on the topopolymerization of the
1,3-butadiyne system.23
SCHEME 5a
Syntheses of the 1,3-butadiynes (16, 17, and 18) were
carried out by oxidative dimerization of the corresponding
5-nitronaphthylethynyl derivative (9, 11, and 13, respec-
tively) under adapted Glaser conditions, using copper(I)
catalyst in dry pyridine under oxygen atmosphere, at 40
°C, in excellent yields, Scheme 6. Compound 16, soluble
in dichoromethane, was isolated in 98% yield as a pale-
brown solid. Compound 17 shows low solubility in dichlo-
romethane and was isolated in 90% yield as a yellow-
brown solid. Compound 18 shows very low solubility in
dichloromethane and was isolated in 80% yield as a
yellow solid.
5-Nit r o-(n a p h t h ylet h yn yl)-[5-(N,N-d im et h yla m i-
n o)]n a p h th a len e Der iva tives, 20, 21, a n d 22. Another
family of 5-nitronaphthylethynyl derivatives has been
synthesized showing a nitro and a N,N-dimethylamino
groups, with opposite electronic character, at the ends
of the conjugated system. The Sonogashira reaction
between iodonaphthyl 19 and the appropriate 5-nitro-
naphthylethynyl derivatives was undertaken. The prepa-
ration of 5-iodo-N,N-dimethylnaphthalene-1-amine 19
was carried out by reduction of 1-iodo-5-nitronaphthalene
(3)with tin(II) chloride dihydrate,24 giving 5-iodonaph-
thalene-1-amine as a pale-brown solid in excellent yield,
which was treated with aqueous formaldehyde (37%) and
sodium cyanoborohydride in glacial acetic acid,25 yielding
quantitatively 19, as a brown-red solid, Scheme 7.
The cross-coupling between the iodo derivative 19 and
5-nitronaphthalene 9, catalyzed by palladium, affords the
conjugated compound 20, as a red-orange solid, in practi-
cally quantitative yield; a charge-transfer band appears
in the UV-vis spectrum (CH2Cl2, in 1 × 10-3 mol L-1),
425 nm (ꢀ, 3985), which for lowest concentrations is
missing.
a
Reagents: i. PdCl2(PPh3)2, Cu2Cl2, NEt3.
1-ethynyl-5-({5-[(5-nitro-1-naphthyl)ethynyl]-1-naphthyl}-
ethynyl)naphthalene (13), as a dark yellow solid in
practically quantitative yield, Scheme 4.
Din itr oa r yl Na n ostr u ctu r es: 1-Nitr o-5-[(5-n itr o-
1-n a p h th yl)eth yn yl]n a p h th a len e a n d 1-Nitr o-5-({5-
[(5-n itr o-1-n a p h th yl)eth yn yl]-1-n a p h th yl}eth yn yl)-
n aph th alen e (14 an d 15). The synthesis of an interesting
family of compounds, containing symmetrical 5-nitronaph-
thylethynyl units, has been carried out.
1-Nitro-5-[(5-nitro-1-naphthyl)ethynyl]naphthalene (14)-
was obtained, by cross-coupling reaction, catalyzed by
palladium, between the compounds 3 and 9, as a yellow
solid in good yield (74%), which shows low solubility in
common organic solvents.22 Furthermore, 1-nitro-5-({5-
[(5-n it r o-1-n a ph t h yl)et h yn yl]-1-n a ph t h yl}et h yn yl)-
naphthalene (15), despite the insolubility observed in 14,
was also prepared. Thus, cross-coupling reaction, cata-
lyzed by palladium, between the iodo derivative 3 and
1-ethynyl-5-[(5-nitro-1-naphthyl)ethynyl]naphthalene (11),
provides 15 as a brown solid in moderate yield (50%),
Scheme 5. The compound shows very low solubility in
dichloromethane and was isolated in pure form by
continuous extraction of the starting reagents.
N,N-Dimethyl-5-({5-[(5-nitro-1-naphthyl)ethynyl]-1-
naphthyl}ethynyl)naphthalen-1-amine (21) was synthe-
sized by cross-coupling between nitronaphthylethynyl
derivative 11 and iodonaphthyl derivative 19, catalyzed
1,4-Di(5-n itr on a p h th yleth yn yl)-1,3-bu ta d iyn es 16,
17, a n d 18: Oxid a tive Dim er iza tion of th e 5-Ni-
tr on a p h th yleth yn yl Der iva tives 9, 11, a n d 13. 1-Ni-
tro-5-[4-(5-nitro-1-naphthyl)buta-1,3-diynyl]naphtha-
(23) Rodr´ıguez, J . G.; et al. To be published.
(24) Bellamy, F. D.; Ou, K. Tetrahedron Lett. 1984, 25, 839.
(25) Borch, R. F.; Hassid, A. I. J . Org. Chem. 1972, 37, 1673.
(22) Rudenko, A. P., Vasiil′iev, A. V. Zh. Org. Khim. 1995, 31(10),
1502-1522.
J . Org. Chem, Vol. 67, No. 22, 2002 7633

Rodr´ıguez and Tejedor
SCHEME 6 a
a
Reagents: i. Cu2Cl2, pyridine, oxygen atmosphere.
SCHEME 7 a
TABLE 1. F lu or escen ce Em ission : F r equ en cies a n d
Qu a n tu m Yield
compound
λem
F
20
21
22
513.42
519.01
542.77
6.15 × 10-4
2.51 × 10-3
1.2 × 10-2
a
In the same way, conjugated compound 22, a 5-naph-
thylethynyl homologue of compound 21 and 20, was
prepared. Cross-coupling between the nitronaphthylethy-
nyl derivative 13 and the iodonaphthyl derivative 19,
catalyzed by palladium, gave N,N-dimethyl-5-{[5-({5-[(5-
nitro-1-naphthyl)ethynyl]-1-naphthyl}ethynyl)-1-naphthyl]-
ethynyl}naphthalen-1-amine (22), as a dark brown solid
in low yield (22%), probably due to the low solubility of
compound 13.
Reagents: i. SnCl2‚2H2O, Cu2Cl2, NEt3.
SCHEME 8 a
5-Nitro-(naphthylethynyl)-[5-(N,N-dimethylamino)]-
naphthalene derivatives (20-22) in solution exhibit a
fluorescence radiation which was analyzed in dichlo-
romethane, Table 1. Remarkably, the quantum yield
increases with the separation distance between the nitro
and the electron-releasing N,N-dimethylamino group in
dichloromethane; the emission wavelength also increases
in 21 and 22 with respect to 20. Thus, when the nitro
and N,N-dimethylamino groups are separated by one or
two 5-naphthylethynyl units (compound 21 or 22) with
respect to 20, the quantum yield is about 4 or 20 times
greater, respectively. The quantum yield is very sensitive
to protic and polar solvents.26
Str u ctu r a l An a lysis of th e Eth yn yln a p h th a len e
Com p ou n d s. All the 5-nitronaphthylethynyl structures
and intermediates were isolated in pure form and identi-
fied unambiguously, in particular by 1H, 13C NMR
a
Reagents: i. Cl2Pd(PPh3)2, Cu2I2, NEt3 (or piperidine for 22).
1
1
(bidimensional H/13C and H/1H), and IR spectroscopy.
by palladium, yielding 21 as an orange solid (60%),
Scheme 8; a charge-transfer band appears in the UV-
vis spectrum (CH2Cl2, in 0.7 × 10-3 mol L-1), 419 nm (ꢀ,
5714), which for lowest concentrations is missing.
(26) Catala´n, J .; Lo´pez, V.; Pe´rez, P.; Mart´ın-Villamil, R.; Rodr´ıguez,
J . G. Liebigs Ann. 1995, 241-252.
7634 J . Org. Chem., Vol. 67, No. 22, 2002

Carbon Networks Based on 1,5-Naphthalene Units
an important single bond character, 1.469(2) Å.30 The
molecular structure consists of two practically planar
conjugated 5-nitronaphthylethynyl-5-(N,N-dimethylami-
no)naphthalene molecules which are disposed in a paral-
lel association overlapping the acceptor nitronaphthalene
with the donor (N,N-dimethylamino)naphthalene rings
of each molecule of the dimer as a charge-transfer
complex, with the nitro and N,N-dimethylamino substi-
tution at the same extreme. Both molecules in the dimer
are related by a symmetry center located in the middle
of the plane formed by C11-C12 triple bond [1.196(2) Å]
of each molecule. The naphthylethynylnaphthalene hy-
drocarbon nucleus in compound 20 is nearly planar with
C3 at -0.104(2), C15 at 0.143(2), and C16 at 0.116(2) in
the maximum deviation from the mean square plane; the
nitrogen in the nitro and N,N-dimethylamino groups are
N1 at 0.120(2) and N2 at -0.068(2) Å, respectively. The
mean interplanar spacing between the two molecules in
the dimer is 3.43 Å, which agrees well with the distances
observed in other π-π naphthalene charge-transfer
complexes.28 The naphthalene rings, around the triple
bond, are disposed in an anti conformation.
Figure 2 shows a projection of the structure under the
a-axis for the molecules of compound 20. The overlapping
between the two molecules related by symmetry center
is practically complete, including the nitro and N,N-
dimethylamino groups, and the intermolecular symmetry
center coincides with the crystallographic one. The mo-
lecular packing in the crystal is governed by van der
Waals interaction between the dimer molecules in a
herringbone type extended form.
F IGURE 1. The molecule numbering with the thermal
ellipsoids at the 50% probability level.
The 13C chemical shifts of a number of the monosubsti-
tuted naphthalenes27 have been reported, and the 13C
chemical shifts of 1,5-disubstituted naphthalenes were
obtained from the parent compounds used in the syn-
thesis of the naphthylethynyl derivatives.
Moreover, by proton/carbon absorption signals in the
spectra, it was assumed that the strong deshielding effect
observed on the peri protons probably also are influenced
by the electron-current anisotropic effect of the triple
bond.
By DSC (25 to 300 °C) only a narrow endothermic peak
was observed corresponding with the melting of the
compounds, and a possible syn conformation disorder
phase was not detected. Thus, an anti conjugated con-
formation in the solid state would be assumed, Schemes
4 and 6.
Compounds 20, 21, and 22, containing nitro and N,N-
dimethylamino groups, in the solid state, show the anti
conformation of the naphthalene rings around the acety-
lene axis, confirmed for 20 by monocrystal X-ray struc-
ture analysis.
Exp er im en ta l Section
Gen er a l. The IR spectra frequencies are given in cm-1. H
1
and 13C NMR spectra were recorded at 300.13 (or 200.13) and
75.47 MHz, respectively. Chemical shifts are given in δ with
TMS as an internal reference, coupling constants J are given
in hertz, and the solvent is indicated with each spectrum. The
UV-vis spectra frequencies are given in nm and ꢀ in L
mol-1.cm-1. Yields are given after chromatography column
separation or solvent extraction.
Cr yst a llogr a p h ic a n d Molecu la r St r u ct u r e of
Com p ou n d 20. The crystal X-ray diffraction analysis of
20 has been carried out. The molecular structure, to-
gether with its numbering scheme, is shown in Figure
1. Bond distances and angles of compound 20 correlate
well with other naphthalene-related structures.23,28 Some
distances in the naphthalene ring show significant devia-
tions due to the stereoelectronic effects of the N,N-
dimethylamino and nitro groups and also to the charge-
transfer association between both molecules forming a
dimer. Thus, C1-C2, C3-C4, C7-C8, C9-C10, C13-
C14, C15-C16, C19-C20, C21-C22 show the shortest
distances (1.359(2)-1.377(2) Å) in the naphthalene rings.
The electron-releasing effect of the N,N-dimethylamino
group was evidenced by the double bond character of
C19-N2 compared with N2-C23 or N2-C24 single
bonds of the same group, 1.413(2) vs 1.454(2) or 1.452(2)
Å,29 while the nitro group shows the C1-N1 bond with
5-Nitr on a p h th a len -1-a m in e (1) a n d 1,5-Dia m in on a p h -
th a len e (2).18 To a suspension of 1,5-dinitronaphthalene (8
g, 0.037 mol) in water (110 mL) was added a solution of
ammonium chloride (14 g, 0.263 mol) in concentrated aqueous
ammonia (28%). The mixture was stirred and warmed at 80-
85 °C, and sodium sulfide (9.5 g, 0.122 mol) was added in three
portions each 10 min. The mixture was heated at 85 °C for 4
h (monitored by TLC) and then filtered through a heated
Bu¨chner funnel. The solid was extracted twice with dichlo-
romethane (10 mL), dried over anhydrous sodium sulfate, and
filtered. After the solvent was removed to afford a residual
solid that was purified by silica gel column chromatography,
elution with hexane/ethyl acetate (2:1) gave two reduction
products, 5-nitronaphthalen-1-amine (1) as a brown-red solid,
mp 88-90 °C, 3.68 g (54%) yield, and 1,5-diaminonaphthalene
(2) as a brown solid, mp 186-188°, 2.04 g (34%) yield, which
agrees well with a commercial sample.
Compound 1: IR (KBr, cm-1): 3343, 1509, 1322, 770. 1H
NMR (300 MHz, CDCl3): δ 8.09 (d, 1H, J ) 11.1 Hz), 8.07 (d,
1H, J ) 12.9 Hz), 7.87 (d, 1H, J ) 12.9 Hz), 7.46 (t, 1H, J )
12.9 Hz), 7.41 (t, 1H, J ) 11.1 Hz), 6.86 (1H, d, J ) 11.1 Hz),
4.26 (s, 2H). 13C NMR (75 MHz, CDCl3): δ 147.33, 142.56,
(27) Carbon-13 NMR Spectroscopy: High-Resolution Methods and
Applications in Organic Chemistry and Biochemistry, 3rd ed.; Breit-
maier, E., Voelter, W., Eds.; VCH Verlagsgesellschaft mbH, D-6940
Weinheim, 1987; pp 262-264.
(28) Rodr´ıguez, J . G.; Vilches, J .; Smith-Verdier, P.; Garc´ıa-Blanco,
S., Tetrahedron 1983, 39(1), 199-201.
(29) Rodr´ıguez, J . G.; Ramos, S.; Mart´ın-Villamil, R.; Fonseca, I.;
and Albert, A. J . Chem. Soc., Perkin Trans.
Rodr´ıguez, J . G.; Lafuente, A.; Mart´ın-Villamil, R.; Martinez-Alcazar,
M. P. J . Phys. Org. Chem., 2001, 14, 1-859-868.
1 1996, 541-543.
(30) Rodr´ıguez, J . G.; Fonseca, I.; Martinez-Carreras, S. J . Chem.
Res. (S) 1991, 8-9. Ibid. (M), 1991, 145-170, and references therein.
J . Org. Chem, Vol. 67, No. 22, 2002 7635

Rodr´ıguez and Tejedor
F IGURE 2. View of the molecular packing of the molecules under the a-axis projection.
129.97, 127.01, 126.01, 124.39, 123.54, 122.66, 113.31, 111.15.
10H8N2O2 (188.06): Anal. Calcd: C 63.83, H 4.28, N 14.89;
found: C 63.91, H 4.25, N 14.64.
aqueous ammonium chloride solution with a little amount of
KCN and extracted with dichloromethane. The extracts were
dried on anhydrous sodium sulfate, and after filtration, the
solvent was removed to give a brown solid, which was purified
by silica gel column chromatography, eluting with hexane/
ethyl acetate (2:1). Compound 5a was isolated as a yellow solid,
mp 107-108 °C, 470 mg (54%) yield; 5b was obtained as a
yellow solid, mp 124-125 °C, 198 mg (26%) yield.
C
1,5-Diiod on a p h th a len e (4). Gen er a l P r oced u r e for
Iod a tion of Am in oa r en es.19,20 To a solution of sodium nitrite
(3 g, 0.044 mol) in concentrated sulfuric acid (25 mL) at 0 °C
was added dropwise a solution of 1,5-diaminonaphthalene (2)
(3 g, 0.019 mol) in glacial acetic acid (25 mL). The mixture
was stirred for 15 min and poured onto ice (50 g) and urea
(0.25 g), and then a solution of potassium iodide (100 g, 0.6
mol) in water (100 mL) was added and stirred overnight under
reduced pressure. The solid was filtered, dried, and extracted
with dichloromethane. The combined extracts were refluxed
with charcoal and finally purified by silica gel column chro-
matography, eluting with hexane/dichloromethane (2:1) to give
4 as pale-yellow needles, mp 148-150 °C (lit.19 mp 147 °C),
4-(5-Iodo-1-naphthyl)-2-methylbut-3-yn-2-ol (5a ): IR (KBr,
1
cm-1): 3323, 2160, 1143, 782. H NMR (200 MHz, CDCl3): δ
8.31 (d, 1H, J ) 8.8 Hz), 8.10 (d, 1H, J ) 7.0 Hz), 8.07 (d, 1H,
J ) 8.4 Hz), 7.68 (d, 1H, J ) 7.2 Hz), 7.48 (dd, 1H, J ) 7.7
Hz), 7.24 (t, 1H, J ) 7.8 Hz), 1,7 (s, 6H). 13C NMR (75 MHz,
CDCl3): δ 137.88, 133.75 (2C), 132.75, 130.98, 127.45, 126.94,
126.67, 120.88, 99.78, 99.33, 79.47, 65.69, 31.52 (2C). C15H13
-
OI (336.00): Anal. Calcd: C 53.59, H 3.90; found: C 53.45, H
3.84.
1
5.55 g (77%) yield. IR (KBr, cm-1): 1131, 780. H NMR (200
MHz, CDCl3): δ 8.13 (d, 4H, J ) 7.6 Hz), 7.26 (t, 2H, J ) 7.6
Hz). 13C NMR (75 MHz, CDCl3): δ 138.54 (2C), 134.64 (2C),
133.59 (2C), 128.41 (2C), 99.68 (2C). C10H6I2 (379.86): Anal.
Calcd: C 31.61, H 1.59; found: C 31.48, H 1.65.
1,5-Di-[4-(2-methylbut-3-yn-2-ol)]-naphthalene (5b): IR (KBr,
1
cm-1): 3335, 2100, 1160, 790. H NMR (200 MHz, CDCl3): δ
8.26 (d, 2H, J ) 8.2 Hz), 7.66 (d, 2H, J ) 7.0 Hz), 7.47 (t, 2H,
J ) 8.2 Hz), 2.32 (s, 2H), 1.73 (s, 12H). 13C NMR (75 MHz,
CDCl3): δ 132.95 (2C), 130.85 (2C), 126.75 (2C), 125.94 (2C),
120.68 (2C), 99.17 (2C), 79.99 (2C), 65.84 (2C), 31.60 (4C).
20H20O2 (292.15): Anal. Calcd: C 82.16, H 6.89; found: C
82.30, H 6.74.
1-Eth yn yl-5-iod on a p h th a len e (6). Gen er a l P r oced u r e
for Ar yla cetylen es.21 To a solution of 5a (88 mg, 0.26 mmol)
in anhydrous toluene (30 mL) was added finely powdered
sodium hydroxide (7 mg, 0,18 mmol), under argon atmosphere,
and the mixture was warmed at the reflux temperature for
1.5 h (monitored by TLC) and then filtered. The solvent was
removed at reduced pressure, and the solid residue was
4-(5-Iod o-1-n a p h t h yl)-2-m et h ylb u t -3-yn -2-ol (5a ) a n d
1,5-Di-[4-(2-m eth ylbu t-3-yn -2-ol)]-n a p h th a len e (5b). Gen -
er a l P r oced u r e of th e Cr oss-Cou p lin g Rea ction . To a
solution of aryl iodide 3 (1 g, 2.6 mmol) and 2-methylbut-3-
yn-2-ol (241 mg, 2.86 mmol) in freshly distilled diethylamine
(or triethylamine) (10 mL), under argon atmosphere and at
room temperature, were added dichloro bis(triphenylphos-
phine)palladium (18 mg, 0.026 mmol) and copper iodide (4.8
mg, 0.003 mmol). The mixture was stirred for 21 h (monitored
by TLC), and then the amine was removed under reduced
pressure. The crude residue was washed with a saturated
C
7636 J . Org. Chem., Vol. 67, No. 22, 2002

Carbon Networks Based on 1,5-Naphthalene Units
purified by silica gel column chromatography, eluting with
hexane to give 6 as a pale brown solid, mp 74-75 °C, 49.5 mg
(68%) yield. UV-vis (CH2Cl2), λ max (nm): 234 (ꢀ, 25777), 297s
(ꢀ, 8399), 307 (ꢀ, 11019), 320s (ꢀ, 8399). IR (KBr, cm-1): 3271,
mp 148-150 °C, 258 mg (89%) yield. UV-vis (CH2Cl2), λ max
(nm): 240 (ꢀ, 22021), 255s (ꢀ, 19933), 321s (ꢀ, 9550), 341 (ꢀ,
10857). IR (KBr, cm-1): 2160, 1513, 1345, 1328, 786. 1H NMR
(300 MHz, CDCl3): δ 8.65 (d, 1H, J ) 8.4 Hz), 8.50 (d, 1H, J
) 8.7 Hz), 8.21 (d, 1H, J ) 7.5 Hz), 7.81 (d, 1H, J ) 7.5 Hz),
7.61 (dd, 1H, J ) 8.7 Hz, J ) 7.5 Hz), 7.59 (t, 1H, J ) 7.5 Hz),
3.56 (s, 1H). 13C NMR (75 MHz, CDCl3): δ 146.94, 134.15,
132.49, 132.41, 128.45, 125.07, 124.90, 124.34, 123.99, 120.75,
83.59, 80.67. C12H7NO2 (197.05): Anal. Calcd: C 73.09, H 3.58,
N 7.10; found: C 72.98, H 3.70, N 76.94.
1
2100, 1023, 784. H NMR (200 MHz, CDCl3): δ 8.39 (d, 1H, J
) 8.2 Hz), 8.12 (d, 2H, J ) 8.4 Hz), 7.77 (d, 1H, J ) 7.5 Hz),
7.50 (dd, 1H, J ) 8.4 Hz, J ) 7.5 Hz), 7.25 (dd, 1H, J ) 8.2
Hz, J ) 8.4 Hz), 3.48 (s, 1H). 13C NMR (75 MHz, CDCl3):
138.19, 134.27, 133.96, 133.55, 132.04, 127.81, 127.15, 126.83,
120.54, 99.78, 82.615, 80.98. C12H7I (277.96): Anal. Calcd: C
51.83, H 2.54; found: C 51.69, H 2.70.
2-Meth yl-4-{5-[(5-n itr o-1-n aph th yl)eth yn yl]-1-n aph th yl}-
bu t-3-yn -2-ol (10). Following the general method used for the
synthesis of 5a , a mixture of dichloro bis(triphenylphosphine)-
palladium (II) 72 mg (0.051 mmol), copper iodide 0.9 mg (0.005
mmol), compound 9 342 mg (0.51 mmol), compound 5a 200
mg (0.51 mmol), and triethylamine 30 mL was stirred for 15
h. Flash chromatography on silica gel, eluting with hexane/
ethyl acetate 3/1, provided 10 as a yellow solid, mp 176-178
°C, 345 mg (84%) yield. IR (KBr, cm-1): 3545, 2160, 1518,
1,5-Dieth yn yln a p h th a len e (7). Following the general
method used for the preparation of 6, a solution of the
compound 5b (210 mg, 0.72 mmol) in anhydrous toluene (30
mL) was stirred with finely powdered sodium hydroxide (40
mg, 1 mmol), at reflux temperature for 20 h. After filtration,
the solvent was removed under reduced pressure giving a
residual solid, which was washed with hexane to give 7 as a
pale-brown solid, mp 147-150 °C (lit.31 mp 150 °C), 127 mg
(100%) yield. UV-vis (CH2Cl2), λ max (nm): 237 (ꢀ, 29604),
312 (ꢀ, 22858), 327 (ꢀ, 19326). IR (KBr, cm-1): 3269, 2100,
792.1H NMR (200 MHz, CDCl3): δ 8.39 (d, 2H, J ) 8.0 Hz),
7.78 (d, 2H, J ) 7.0 Hz), 7.52 (t, 2H, J ) 8.0 Hz), 3.49 (s,
2H).13C NMR (75 MHz, CDCl3): δ 133.22 (2C), 131.81 (2C),
127.33 (2C), 126.11 (2C), 120.26 (2C), 82.43 (2C), 81.45 (2C).
1
1329, 1160, 782. H NMR (300 MHz, CDCl3): δ 8.85 (d, 1H, J
) 8.4 Hz), 8.55 (d, 1H, J ) 9.0 Hz), 8.46 (d, 1H, J ) 8.7 Hz),
8.35 (d, 1H, J ) 8.7 Hz), 8.26 (d, 1H, J ) 7.2 Hz), 7.97 (d, 1H,
J ) 6.9 Hz), 7.90 (d, 1H, J ) 6.9 Hz), 7.73 (d, 1H, J ) 7.5 Hz),
7.72 (t, 1H, J ) 7.6 Hz), 7.66 (t, 1H, J ) 8.0 Hz), 7.59 (t, 1H,
J ) 7.8 Hz), 7.56 (t, 1H, J ) 7.8 Hz), 1.76 (s, 6H). 13C NMR
(75 MHz, CDCl3): δ 147.07, 134.00, 133.17, 132.94, 132.71,
131.79, 131.34, 131.11, 128.74, 127.50, 126.71, 126.34, 126.12,
125.19, 125.06, 124.40, 123.69, 121.98, 121.07, 120.78, 99.44,
93.68, 91.55, 79.91, 65.91, 31.63 (2C). C27H19NO3 (405.14):
Anal. Calcd: C 79.98, H 4.72, N 3.45; found: C 80.09, H 4.58,
N 3.62.
C
14H8 (176.06): Anal. Calcd: C 95.42, H 4.58; found: C 95.49,
H 4.51.
1-Iod o-5-n itr on a p h th a len e (3). Following the general
method used for the preparation of 4, to a solution of sodium
nitrite (805 mg, 11.7 mmol) in concentrated sulfuric acid (8
mL), at 0 °C was dropped a solution of 1 (2 g, 10.6 mmol) in
glacial acetic acid (15 mL) and stirred for 30 min. Then, the
mixture was poured on ice (14 g), urea (0.14 g), potassium
iodide (29 g, 0.2 mol), and water (29 mL) and stirred overnight.
The solid was filtered, dried, and extracted with dichlo-
romethane. After the solvent was removed and the residual
solid was purified by flash chromatography on silica gel,
eluting with hexane/ethyl acetate 2:1 gave 3 as a pale-yellow
solid, mp 155-156 °C, 2.42 g (76%) yield. IR (KBr, cm-1): 1514,
1322, 1150, 780. 1H NMR (200 MHz, CDCl3): δ 8.47 (d, 2H,
J ) 8.6 Hz), 8.24 (d, 1H, J ) 7.6 Hz), 8.22 (d, 1H, J ) 7.8
Hz), 7.64 (t, 1H, J ) 8.6 Hz), 7.38 (dd, 1H, J ) 7.6 Hz, J ) 8.6
Hz). 13C NMR (75 MHz, CDCl3): δ 147.11, 139.24, 138.52,
134.69, 129.91, 125.71 (2C), 124.18, 123.71, 99.76. C10H6NO2I
(298.94): Anal. Calcd: C 40.16, H 2.02, N 4.68; found: C 39.99,
H 2.18, N 4.65.
1-E t h yn yl-5-[(5-n it r o-1-n a p h t h yl)e t h yn yl]n a p h t h a -
len e (11). Following the general method used for the synthesis
of 6, a mixture of compound 10 (220 mg, 0.54 mmol),
anhydrous toluene (40 mL), and finely powdered sodium
hydroxide (2 mg, 0.54 mmol) was stirred for 12 h and then
filtered. The residual solid was washed with hexane, giving
11 as a yellow-brown solid, mp 205-206 °C (205.3 °C DSC),
186 mg (100%) yield. UV-vis (CH2Cl2), λ max (nm): 243 (ꢀ,
23134), 336 (ꢀ, 8308), 368s (ꢀ, 5948). IR (KBr, cm-1): 3263,
2227, 2197, 1521, 1342, 1330, 781. 1H NMR (300 MHz,
CDCl3): δ 8.88 (d, 1H, J ) 8.7 Hz), 8.57 (d, 1H, J ) 8.7 Hz),
8.52 (d, 1H, J ) 8.4 Hz), 8.45 (d, 1H, J ) 8.7 Hz), 8.29 (d, 1H,
J ) 7.8 Hz), 8.01 (d, 1H, J ) 7.5 Hz), 7.94 (d,1H, J ) 6.9 Hz),
7.83 (d, 1H, J ) 6.9 Hz), 7.75 (dd, 1H, J ) 8.7 Hz, J ) 7.5 Hz),
7.72 (dd, 1H, J ) 8.7 Hz, J ) 7.8 Hz), 7.62 (dd, 1H, J ) 6.9
Hz, J ) 8.7 Hz), 7.59 (dd, 1H, J ) 6.9 Hz, J ) 8.4 Hz), 3.53 (s,
1H, H-20). 13C NMR (75 MHz, CDCl3): δ 147.16, 134.10,
133.50, 132.96, 132.75, 131.96, 131.90, 131.44, 128.75, 127.56,
127.32, 126.38, 126.31, 125.29, 125.15, 124.42, 123.79, 122.02,
120.89, 120.54, 93.63, 91.65, 82.67, 81.42. MS (70 eV): 347
(M+, 100), 317 (34), 300 (47), 287 (17), 149 (18). C24H13NO2
(347.09): Anal. Calcd: C 82.98, H 3.77, N 4.03; found: C 83.12,
H 3.60, N 4.20.
2-Meth yl-4-(5-n itr o-1-n a p h th yl)bu t-3-yn -2-ol (8). Fol-
lowing the general method for the preparation of 5a , a mixture
of dichloro bis(triphenylphosphine)palladium (11.8 mg, 0.017
mmol), copper iodide (0.3 mg, 0.002 mmol), compound 3 (500
mg, 1.67 mmol), 2-methylbut-3-yn-2-ol (169 mg, 2 mmol), and
triethylamine (20 mL) was stirred for 13 h. Flash chromatog-
raphy on silica gel, eluting with hexane/ethyl acetate 2:1
afforded 8 as a red oil, 375 mg (89%) yield. IR (KBr, cm-1):
3375, 2227, 1523, 1343, 1165, 790. 1H NMR (300 MHz,
CDCl3): δ 8.40 (d, 1H, J ) 8.4 Hz), 8.26 (d, 1H, J ) 8.7 Hz),
8.01 (d, 1 H, J ) 7.8 Hz), 7.55 (d, 1H, J ) 6.9 Hz), 7.40 (dd,
1H, J ) 8.4 Hz, J ) 7.8 Hz), 7.36 (t, 1H, J ) 7.8 Hz), 3.32 (s,
1H), 1.71 (s, 6H). 13C NMR (75 MHz, CDCl3): δ 146.71, 133.77,
132.45, 131.45, 128.38, 124.78, 124.71, 124.16, 123.23, 121.31,
100.39, 79.08, 65.71, 31.45 (2C). C15H13NO3 (255.09): Anal.
Calcd: C 70.58, H 5.13, N 5.49; found: C 70.62, H 5.22, N
5.35.
2-Me t h y l-4-[5-({5-[(5-n it r o -1-n a p h t h y l)e t h y n y l]-1-
n a p h th yl}eth yn yl)-1-n a p h th yl]bu t-3-yn -2-ol (12). Follow-
ing the general method used for the synthesis of 5a , a mixture
of dichloro bis(triphenylphosphine) palladium (81 mg, 0.115
mmol), copper iodide (2 mg, 0.011 mmol), compound 11 (400
mg, 1.15 mmol), compound 5a (387 mg, 1.15 mmol), and
triethylamine (50 mL) was stirred for 72 h at the reflux
temperature. Flash chromatography on silica gel, eluting with
hexane/dichloromethane 1:4 gives 12 as a brown solid, mp
249-251 °C, 319 mg (50%) yield.IR (KBr, cm-1): 3500, 2226,
1-Eth yn yl-5-n itr on a p h th a len e (9). Following the general
method used for the preparation of 6; a mixture of the
compound 8 (375 mg, 1.47 mmol), anhydrous toluene (80 mL),
and finely powdered sodium hydroxide (41 mg, 1.03 mmol) was
stirred for 20 h. Flash chromatography on silica gel, eluting
with hexane/ethyl acetate 2:1, gave 9 as a pale-yellow solid,
1
2198, 1518, 1340, 1328, 1164, 781. H NMR (300 MHz, NO2-
benzene[d5], 80 °C): δ 8.04 (d, 1H, J ) 8.7 Hz), 7.82 (d, 1H, J
) 8.4 Hz), 7.78 (d, 1H, J ) 9.0 Hz), 7.75 (d, 1H, J ) 7.8 Hz),
7.61 (d, 1H, J ) 9 Hz), 7.57 (d, 1H, J ) 9.6 Hz), 7.34 (d, 1H,
J ) 8.1 Hz), 7.13 (d, 2H, J ) 6.9 Hz), 7.09 (d, 2H, J ) 8.1 Hz),
1
6.88-6.70 (m, 7H), 0.97 (s, 6H). H NMR (300 MHz, CDCl3):
(31) Rohde, O.; Wegner, G. Makromol. Chem. 1978, 179, 2013.
δ 8.92 (d, 1H, J ) 8.4 Hz), 8.64 (d, 1H, J ) 8.4 Hz), 8.59 (d,
J . Org. Chem, Vol. 67, No. 22, 2002 7637

Rodr´ıguez and Tejedor
1H, J ) 9.0 Hz), 8.56 (d, 2H, J ) 9.0 Hz), 8.37 (d, 1H, J ) 8.4
Hz), 8.31 (d, 1H, J ) 7.8 Hz), 8.04 (d, 1H, J ) 6.9 Hz), 7.98 (d,
2H, J ) 6.6 Hz), 7.94 (d, 1H, J ) 6.6 Hz), 7.80-7.56 (m, 7H),
1.76 (s, 6H). 13C NMR (75 MHz, NO2-benzene[d5], 80 °C): δ
133.54, 132.69, 132.20, 131.95, 131.76, 131.60, 131.42, 131.31,
127.91, 127.58, 127.41, 127.01, 126.84, 126.66, 126.59, 125.68,
124.50, 122.35, 101.09, 94.18, 93.45, 93.04, 92.29, 79.88, 65.86,
31.76 (2C). Twelve carbons missing as a result of overlap.
(60 mg, 0.3 mmol) in dry pyridine (10 mL), and the mixture
was stirred for 5 h. After, solvent was removed to give a
residual solid that was washed with ammonium hydroxide till
the blue color disappeared, and then it was extracted with
dichloromethane. The organic layer was dried on anhydrous
magnesium sulfate and after filtration and solvent evaporation
was obtained a brown solid, that was purified by silica gel
column chromatography, eluting with hexane/dichloromethane
1:1 to give 16 as a pale-brown solid, mp 236-238 °C (dark,
dec; DSC), 116 mg (98%) yield. UV-vis (CH2Cl2), λ max (nm):
244 (ꢀ, 28417), 379 (ꢀ, 16327), 290 (ꢀ, 10191). IR (KBr, cm-1):
2160, 1521, 1349, 1326, 787. 1H NMR (300 MHz, CDCl3): δ
8.75 (d, 2H, J ) 8.1 Hz), 8.60 (d, 2H, J ) 8.4 Hz), 8.29 (d, 2H,
J ) 7.8 Hz), 7.97 (d, 2H, J ) 7.2 Hz), 7.72 (t, 4H, J ) 7.95
Hz). 13C NMR (75 MHz, CDCl3): δ 147.21 (2C), 134.62 (2C),
133.42 (2C), 132.46 (2C), 128.65 (2C), 125.57 (2C), 125.15 (2C),
124.84 (2C), 124.63 (2C), 120.32 (2C), 80.54 (2C), 79.55 (2C).
MS (70 eV): 392 (M+, 100), 362 (12), 346 (3), 334 (6), 316 (9),
300 (19), 298 (34), 288 (24), 287 (33), 149 (19). C24H12N2O4
(392.08): Anal. Calcd: C 73.47, H 3.08, N 7.14; found: C 73.25,
H 3.27, N 7.39.
C
39H25NO3 (555.18): Anal. Calcd: C 84.31, H 4.54, N 2.52;
found: C 84.18, H 4.48, N 2.71.
1-E t h y n y l-5-({5-[(5-n i t r o -1-n a p h t h y l)e t h y n y l]-1-
n a p h th yl}eth yn yl)n a p h th a len e (13). Following the general
method used for the preparation of 6, a mixture of compound
12 (200 mg, 0.36 mmol), anhydrous toluene (100 mL), and
finely powdered sodium hydroxide (14.4 mg, 0.36 mmol) was
stirred for 72 h and then filtered. The residual solid was
washed with HCl (20%) and hot toluene to give 13 as a dark
yellow solid, mp 235-237 °C, 177 mg (100%) yield, which
shows low solubility in organic solvents. UV-vis (CH2Cl2), λ
max (nm): 232 (ꢀ, 70409), 301s (ꢀ, 8882), 362 (ꢀ, 19897). IR
(KBr, cm-1): 3260, 2226, 2196, 1521, 1342, 1330, 782. 1H NMR
(300 MHz, NO2-benzene[d5], 80 °C): δ 8.50 (d, 1H, J ) 8.4
Hz), 8.28-8.22 (m, 3H), 8.03 (d, 1H, J ) 8.4 Hz), 7.98 (d, 1H,
J ) 8.4 Hz), 7.79 (d, 1H, J ) 7.5 Hz), 7.59 (d, 2H, J ) 6.6 Hz),
7.57 (d, 1H, J ) 6.3 Hz), 7.54 (d, 1H, J ) 6.9 Hz), 7.37-7.26
(m, 7H), 3.29 (s, 1H). MS (70 eV): 497 (M+, 100), 467 (6), 450
(10), 449 (14), 448 (22), 224 (21). C36H19NO2 (497.14): Anal.
Calcd: C 86.90, H 3.85, N 2.82; found: C 87.15, H 3.69, N
2.95.
1-Nit r o-5-{[5-(4-{5-[(5-n it r o-1-n a p h t h yl)e t h yn yl]-1-
n a p h t h y l }b u t a -1 ,3 -d i y n y l )-1 -n a p h t h y l ]e t h y n y l }-
n a p h th a len e (17). Following the general method used for the
synthesis of 16, a mixture of cuprous chloride (3,2 mg, 0.016
mmol) in dry pyridine (20 mL) and a solution of compound 11
(110 mg, 0.32 mmol) in dry pyridine (10 mL) was stirred for 7
h. After solvent was removed, the residual solid was washed
with ammonium hydroxide till the blue color disappeared. The
extraction was carried out with abundant dichloromethane
(800 mL). The organic layer was dried on anhydrous magne-
sium sulfate and after filtration and solvent evaporation was
obtained a solid, that was washed with hexane, EtOH, and
Et2O till the starting compounds were removed. Compound
17 was isolated as a yellow-brown solid, mp > 158 °C (darken,
dec DSC), 100 mg (90%) yield, which shows low solubility in
organic solvents. UV-vis (CH2Cl2), λ max (nm): 232 (ꢀ, 39182),
373 (ꢀ, 12784). IR (KBr, cm-1): 2259, 1527, 1363, 784. 1H NMR
(300 MHz, NO2-benzene[d5], 85 °C): δ 8.39 (d, 2H, J ) 8.4
Hz), 8.19 (d, 2H, J ) 8.7 Hz), 7.94 (d, 2H, J ) 7.5 Hz), 7.65 (d,
2H, J ) 8.1 Hz), 7.56 (d, 2H, J ) 8.7 Hz), 7.48-7.26 (m, 14H).
MS (MALDI-TOF): 692.2. C48H24N2O4 (692.17): Anal. Calcd:
C 83.23, H 3.49, N 4.04; found: C 83.14, H 3.62, N 4.38.
1-Nitr o-5-[(5-n itr o-1-n aph th yl)eth yn yl]n aph th alen e (14).
Following the general method discussed for 5a ; a mixture of
dichloro bis(triphenylphosphine)palladium (36 mg, 0.051 mmol),
copper iodide (0.9 mg, 0.005 mmol), compound 9 (100 mg, 0.51
mmol), compound 3 (152 mg, 0.51 mmol), and triethylamine
(30 mL) was stirred for 15 h; the solvent was removed to give
a brown solid that was washed with hexane, EtOH, and CH2-
Cl2 until the starting compounds were removed, affording 14
as a yellow solid, mp 187.6 °C (DSC), 139 mg (74%) yield,
which shows low solubility in organic solvents. UV-vis (CH2-
Cl2), λ max (nm): 232 (ꢀ, 65700), 262s (ꢀ, 21883), 371 (ꢀ, 25746).
IR (KBr, cm-1): 1521, 1347, 789.1H NMR (300 MHz, NO2-
benzene[d5], 90 °C): δ 8.59 (d, 2H, J ) 8.7 Hz), 8.19 (d, 2H, J
) 8.7 Hz), 7.94 (d, 2H, J ) 7.5 Hz), 7.65 (d, 2H, J ) 7.2 Hz),
7.49-7.37 (m, 4H). MS (70 eV): 368 (M+, 100), 338 (20), 308
(4), 276 (24), 274 (38), 137 (12). C22H12N2O4 (368.08): Anal.
Calcd: C 71.74, H 3.28, N 7.61; found: C 71.52, H 3.31, N
7.84.
1-Nitr o-5-({5-[(5-{4-[5-({5-[(5-n itr o-1-n aph th yl)eth yn yl]-
1-n aph th yl}eth yn yl)-1-n aph th yl]bu ta-1,3-diyn yl}-1-n aph -
th yl)eth yn yl]-1-n a p h th yl}eth yn yl)n a p h th a len e (18). Fol-
lowing the general method used for the preparation of 16, a
mixture of cuprous chloride (1,2 mg, 0.006 mmol) in dry
pyridine (20 mL) and compound 13 (60 mg, 0.32 mmol) in dry
pyridine (20 mL) was stirred for 10 h. After solvent was
removed, the residual solid was washed with ammonium
hydroxide till the blue color disappeared. The solid was
extracted with abundant dichloromethane (800 mL). Com-
pound 18 was obtained as a yellow solid, mp > 250 °C (darken,
dec; DSC), 50 mg (80%) yield, which shows very low solubility
in organic solvents. UV-vis (CH2Cl2), λ max (nm): 236 (ꢀ,
205000), 362 (ꢀ, 102410). IR (KBr, cm-1): 2258, 1524, 1312,
1-Nitr o-5-({5-[(5-n itr o-1-n aph th yl)eth yn yl]-1-n aph th yl}-
eth yn yl)n a p h th a len e (15). Following the method for the
synthesis of 5a , a mixture of dichloro bis(triphenylphosphine)-
palladium (20 mg, 0.029 mmol), copper iodide (0.6 mg, 0.003
mmol), compound 11 (100 mg, 0.29 mmol), compound 3 (87
mg, 0.51 mmol), and triethylamine (50 mL), was stirred for
24 h at 40 °C. After, the crude was hydrolyzed and extracted
with abundant dichloromethane (500 mL). The solvent was
removed, and the residual solid was washed with hexane and
hot EtOH till the reagents were removed, giving 15 as a brown
solid, mp > 295 °C (darken, dec), 75 mg (50%) yield, which
shows very low solubility in organic solvents.
1
781. H NMR (300 MHz, NO2-benzene[d5], 85 °C): δ 8.67 (d,
2H, J ) 8.1 Hz), 8.46-8.39 (m, 6H), 8.21 (d, 2H, J ) 8.9 Hz),
8.14 (d, 2H, J ) 8.5 Hz), 7.98 (d, 2H, J ) 7.7 Hz), 7.77 (d, 4H,
J ) 6.1 Hz), 7.75 (d, 2H, J ) 5.7 Hz), 7.72 (d, 2H, J ) 7.3 Hz),
7.55-7.34 (m, 14H). MS (MALDI-TOF): 992.2. C72H36N2O4
(992.17): Anal. Calcd: C 87.08, H 3.65, N 2.82; found: C 87.15,
H 3.87, N 3.11.
UV-vis (CH2Cl2), λ max (nm): 231 (ꢀ, 98187), 373 (ꢀ, 41284).
IR (KBr, cm-1): 2198, 1521, 1348, 1328, 781.1H NMR (300
MHz, NO2-benzene[d5], 85 °C): δ 8.65, 8.41, 8.20. Fifteen
carbons are missing as a result of overlap. MS (70 eV): 518
(M+, 100), 488 (8), 472 (3), 426 (5), 424 (23), 213 (11).
C
34H18N2O4 (518.13): Anal. Calcd: C 78.76, H 3.50, N 5.40;
5-Iodo-N,N-dim eth yln aph th alen e-1-am in e (19). (a) 5-Io-
d on a p h th a len e-1-a m in e.18 To a solution of compound 3 (600
mg, 2 mmol) in ethyl acetate (freshly distilled) (30 mL) was
added SnCl2-2H2O (2.3 g, 0.01 mol), under argon atmosphere.
The mixture was stirred for 10 h at the reflux temperature
and then poured onto ice (75 g). The pH of the mixture was
made basic (9-10) by addition of aqueous sodium hydroxide
found: C 78.89, H 3.34, N 5.67.
1-Nitr o-5-[4-(5-n itr o-1-n a p h th yl)bu ta -1,3-d iyn yl]n a p h -
th a len e (16) by Hom ocou p lin g Rea ction of Ar yla cety-
len e. Gen er a l P r oced u r e. To a solution of cuprous chloride
(3 mg, 0.015 mmol) in dry pyridine (20 mL), under oxygen
atmosphere at 40 °C, was added a solution of arylacetylene 9
7638 J . Org. Chem., Vol. 67, No. 22, 2002

Carbon Networks Based on 1,5-Naphthalene Units
and finally was extracted with dichloromethane. The organic
layer was dried over anhydrous sodium sulfate, and after
filtration, the solvent was removed. The residual brown solid
was purified by silica gel column chromatography, eluting with
dichloromethane/hexane 2:1 to give 5-iodonaphthalene-1-
amine as a pale-brown solid, mp 63-64 °C, 500 mg (93%) yield.
IR (KBr, cm-1): 3380, 3209, 1392, 1181, 777. 1H NMR (200
MHz, CDCl3): δ 8.08 (d, 1H, J ) 7.4 Hz), 7.83 (d, 1H, J ) 8.8
Hz), 7.57 (d, 1H, J ) 8.6 Hz), 7.37 (dd, 1H, J ) 8.6 Hz, J ) 7.4
Hz), 7.13 (dd, 1H, J ) 7.6 Hz, J ) 8.8 Hz), 6.84 (d, 1H, J ) 7.6
Hz), 4.18 (s, 2H). 13C NMR (75 MHz, CDCl3): δ 142.39, 137.69,
135.10, 127.98, 125.52, 123.99, 123.35, 121.68, 110.66, 100.49.
) 768, µ ) 0.686(1) mm-1, at 296 K. Intensities were collected
in ω - 2θ scan mode using Cu KR (λ ) 1.54180 Å) radiation
with a graphite monochromator (-9 < h <9; 0 < k <10; 0 <
l <33) up to θ ) 76°. Two reference reflections after every 90
min showed negligible variation. From 3312 reflections mea-
sured, the structure was solved by direct methods33 and
difference Fourier techniques; no absorption correction was
applied. After preliminary adjustment of the heavy atoms,
H-atoms were positioned from difference Fourier maps and
then the coordinates refined. Thereafter, several cycles of full-
matrix least-squares calculations were carried out for heavy
atoms, with anisotropic thermal parameters and the hydrogens
atoms included as fixed contributors.34 The refinement con-
verged at R ) 0.0348 and Rw ) 0.0975 for I > 2σ and R )
0.0476 and Rw ) 0.1045 for all data. A weighting scheme to
prevent trends in w∆2F vs Fo and vs <sin θ//λ> was applied.
Largest differences of peak and hole were 0.104 and -0.115 e
Å-3. The atomic scattering factors and the anomalous disper-
sion correction were taken from the International Tables for
X-ray Crystallography.35
N,N-Dim et h yl-5-({5-[(5-n it r o-1-n a p h t h yl)et h yn yl]-1-
n a p h th yl}eth yn yl)n a p h th a len -1-a m in e (21). Following the
general method used for the preparation of 5a , a mixture of
dichloro bis(triphenylphosphine)palladium (24 mg, 0.034 mmol),
copper iodide (1 mg, 0.003 mmol), compound 11 (118 mg, 0.34
mmol), compound 19 (100 mg, 0.34 mmol), and triethylamine
(30 mL) was stirred for 40 h. Flash chromatography on silica
gel, eluting with hexane/dichloromethane (1:1), gave compound
21 as an orange-yellow solid, mp 195-198 °C, 105 mg (60%)
yield. UV-vis (CH2Cl2), λ max (nm): 232 (ꢀ, 33997), 372 (ꢀ,
30377). IR (KBr, cm-1): 2202, 1522, 1342, 1329, 1419, 797.
1H NMR (300 MHz, CDCl3): δ 8.92 (d, 1H, J ) 8.7 Hz), 8.65
(d, 1H, J ) 8.7 Hz), 8.58 (d, 1H, J ) 9.0 Hz), 8.54 (d, 1H, J )
8.7 Hz), 8.32 (d, 1H, J ) 8.7 Hz), 8.30 (d, 1H, J ) 8.4 Hz),
8.26 (d, 1H, J ) 8.1 Hz), 8.03 (d, 1H, J ) 7.2 Hz), 7.97 (d, 2H,
J ) 6.9 Hz), 7.89 (d, 1H, J ) 7.2 Hz), 7.77 (dd, 1H, J ) 8.7 Hz,
J ) 7.2 Hz), 7.71 (t, 1H, J ) 7.8 Hz), 7.67 (dd, 2H, J ) 8.4 Hz,
J ) 7.2 Hz), 7.56 (t, 1H, J ) 8.4 Hz), 7.52 (dd, 1H, J ) 8.7 Hz,
J ) 7.2 Hz), 7.17 (d, 1H, J ) 6.6 Hz), 2.93 (s, 6H). 13C NMR
(75 MHz, CDCl3): δ 151.48, 147.15, 134.68, 134.09, 133.23,
133.15, 132.80, 131.88, 131.44, 131.20, 130.67, 128.78, 127.88
(2C), 126.92, 126.75, 126.57, 126.27, 125.44, 125.26, 125.13,
124.52, 124.43, 123.72, 122.06, 122.00, 121.03, 120.94, 120.86,
114.70, 93.78, 93.66, 91.73, 91.60, 45.37 (2C). MS (70 eV): 516
(M+, 100), 486 (6), 470 (4), 424 (8), 212 (12). C36H24N2O2
(516.18): Anal. Calcd: C 83.70, H 4.68, N 5.42; found: C 83.79,
H 4.44, N 5.71.
C
10H8NI (268.97): Anal. Calcd: C 44.64, H 3.00, N 5.21;
found: C 42.97, H 3.18, N 5.09.
(b) 5-Iod o-N,N-d im eth yln a p h th a len e-1-a m in e (19).19,20
To a solution of compound 5-iodonaphthalene-1-amine (100
mg, 0.37 mmol) and aqueous formaldehyde (37%, 100 mg, 0.37
mmol) in acetonitrile (20 mL) and under argon atmosphere
was slowly added sodium cyanoborohydride (70 mg, 1.11
mmol). The mixture was stirred at room temperature, and
glacial acetic acid (0.08 mL) was slowly added (for 1 h). The
mixture was stirred for 4 h and then washed with two portions
of KOH (pH 9-10) and extracted with dichloromethane. The
organic layer was dried over anhydrous sodium sulfate, and
after filtration, solvent was removed. The solid residual was
purified by silica gel column chromatography, eluting with
hexane/dichloromethane (1:1) to give 19 as a brown-red solid,
mp 40-42 °C, 100 mg (100%) yield. IR (KBr, cm-1): 1388, 933,
1
780. H NMR (300 MHz, CDCl3): δ 8.35 (d, 1H, J ) 8.4 Hz),
8.13 (d, 1H, J ) 7.2 Hz), 7.88 (d, 1H, J ) 8.4 Hz), 7.53 (t, 1H,
J ) 7.8 Hz), 7.21 (dd, 1H, J ) 8.4 Hz, J ) 7.2 Hz), 7.17 (d, 1H,
J ) 7.2 Hz), 2.92 (s, 6H).13C NMR (75 MHz, CDCl3): δ 151.15,
137.42, 135.41, 129.59, 127.33, 126.94, 125.87, 125.09, 114.76,
99.87, 45.33 (2C). C12H12NI (297.00): Anal. Calcd: C 48.51, H
4.07, N 4.71; found: C 48.35, H 4.29, N 4.65.
N,N-Dim eth yl-5-[(5-n itr o-1-n aph th yl)eth yn yl]n aph th a-
len -1-a m in e (20). Following the general method used for the
preparation of 5a , a mixture of dichloro bis(triphenylphos-
phine)palladium (36 mg, 0.051 mmol), copper iodide (1 mg,
0.005 mmol), compound 9 (100 mg, 0.51 mmol), compound 19
(150 mg, 0.51 mmol), and triethylamine (40 mL) was stirred
for 20 h. Flash chromatography on silica gel, eluting with
hexane/dichloromethane 3:1, provides 20 as a red-orange solid,
mp 137.5 °C (DSC), 181 mg (97%) yield. UV-vis (CH2Cl2), λ
max (nm): 238 (ꢀ, 50072), 262s (ꢀ, 17711), 328 (ꢀ, 13817), 371
(ꢀ, 13059). IR (KBr, cm-1): 2200, 1518, 1341, 1325, 1414, 779.
1H NMR (300 MHz, CDCl3): δ 8.90 (d, 1H, J ) 8.1 Hz), 8.55
(d, 1H, J ) 8.7 Hz), 8.34 (d, 1H, J ) 8.4 Hz), 8.27 (d, 1H, J )
7.2 Hz), 8.19 (d, 1H, J ) 8.4 Hz), 7.99 (d, 1H, J ) 7.2 Hz),
7.87 (d, 1H, J ) 6.9 Hz), 7.72 (t, 1H, J ) 8.4 Hz), 7.67 (t, 1H,
J ) 7.8 Hz), 7.55 (t, 1H, J ) 8.0 Hz), 7.52 (t, 1H, J ) 7.8 Hz),
7.17 (d, 1H, J ) 7.5 Hz), 2.93 (s, 6H). 13C NMR (75 MHz,
CDCl3): δ 151.53, 147.07, 134.61, 134.10, 132.84, 131.69,
130.82, 128.80, 128.76, 127.07, 125.77, 125.23, 124.99, 124.47,
124.35, 123.43, 122.33, 120.70, 120.57, 114.77, 94.55, 90.96,
45.22 (2C). MS (70 eV): 366 (M+, 100), 336 (9), 304 (19), 292
(4), 276 (24), 138 (20). C24H18N2O2 (366.14): Anal. Calcd: C
78.67, H 4.95, N 7.65; found: C 78.82, H 5.12, N 7.49.
N,N-Dim eth yl-5-{[5-({5-[(5-n itr o-1-n a p h th yl)eth yn yl]-
1-n a p h th yl}eth yn yl)-1-n a p h th yl]eth yn yl}n a p h th a len -1-
a m in e (22). Following the general method used for the
preparation of 5a , a mixture of dichloro bis(triphenylphos-
phine)palladium (30 mg, 0.042 mmol), copper iodide 0.8 mg,
0.004 mmol), compound 13 (100 mg, 0.21 mmol), compound
19 (62 mg, 0.51 mmol), and piperidine (50 mL) was warmed
at reflux temperature for 4 days. The crude residue after
hydrolysis was extracted with abundant dichloromethane (800
mL). Compound 22 was obtained as a dark brown solid, mp >
298 °C (dark, dec), 30 mg (22%) yield, which shows very low
(32) The crystallographic data of compound 20 (excluding structure
factors) has been deposited with the Cambridge Crystallographic
Data Centre as supplementary publication no. CCDC 186048. A
copy of the data can be obtained free of charge on application to
the CCDC, 12 Union Road, Cambridge CB2 1EZ, UK (E-mail: deposit@
ccdc.cam.ac.uk).
(33) Altomare, A.; Cascarano, G.; Giacovazzo, C.; Guagliardi, A. Dip.
Geomineralogico, University of Bari; M. C. Burla, G. Polidori. Dip.
Scienze della Terra, U. of Perugia; M. Camalli, Ist. Strutt. Chimica,
CNR, Monterrotondo Stazione, Roma. SIR92, 1992.
(34) Hall, S. R. Crystallography Centre, University of Western
Australia. Stewart, J . M. Chemistry Department, University of
Maryland. XTAL3.0, 1990.
(35) International Tables for X-ray Crystallography; Kinoch: Bir-
mingham, 1974; Vol 4.
Cr ysta l Str u ctu r e of Com p ou n d 20. Crystals of composi-
tion C48H36N4O4 (dimer of compound 20) were grown from a
dichloromethane solution as orange prisms.32 A prismatic
crystal of 0.20 × 0.15 × 0.10 mm was selected for X-ray
analysis using a rotary anode diffractometer, with graphite-
monochromated Cu KR radiation.
Sixty reflections up to 2θ ) 70° were measured for the
refinement of the lattice constants. The crystals are monoclinic
and belong to the space group P21/c. Accurate cell constants
were a ) 7.8944(1), b ) 8.2364(1), c ) 28.0376(4) Å, â ) 92.790-
(1)°, V ) 1820.88(4) Å3, Z ) two dimer molecules (or four
molecules of 20). Dc ) 1.337(2) mg m-3, M ) 732.326, F(000)
J . Org. Chem, Vol. 67, No. 22, 2002 7639

Rodr´ıguez and Tejedor
solubility in organic solvents. UV-vis (CH2Cl2), λ max (nm):
231 (ꢀ, 13677), 298 (ꢀ, 4650), 318 (ꢀ, 4877), 340 (ꢀ, 5451), 372
(ꢀ, 6109). IR (KBr, cm-1): 2166, 1524, 1344, 1443, 788. 1H
NMR (300 MHz, NO2-benzene[d5], 85 °C): δ 8.66 (d, 1H, J )
7.8 Hz), 8.48 (d, 1H, J ) 8.4 Hz), 8.45 (d, 1H, J ) 7.8 Hz),
8.41 (d, 1H, J ) 9.0 Hz), 8.21-7.65 (m, 11H), 7.56-711 (m,
8H), 6.89 (d, 1H, J ) 7.5 Hz), 2.93 (s, 6H). MS (70 eV): 666
(M+, 17). MS (MALDI-TOF): 666.0. C48H30N2O2 (666.23):
Anal. Calcd: C 86.46, H 4.54, N 4.20; found: C 86.57, H 4.40,
N 4.47.
Su p p or t in g In for m a t ion Ava ila b le: The structural
assignments and spectral data (1H, 13C and bidimensional
1H/13C and 1H/1H) of compounds 3, 9, 11, 19, and 20. This
material is available free of charge via the Internet at
http://pubs.acs.org.
Ack n ow led gm en t. We thank to the CAICYT of
Spain for financial support of this research (project,
PB97-0060).
J O0203589
7640 J . Org. Chem., Vol. 67, No. 22, 2002