Synthesis of novel push-pull unsymmetrically substituted alkynyl phthalocyanines

Article abstract of DOI:10.1021/jo991843f

Two families of 'push-pull' phthalocyanines 1-3 having an unusually strong dipole moment have been prepared. The syntheses of unsymmetrically substituted phthalocyanines 1a,b and 2 bearing one or two electron- withdrawing 4-nitrophenylethynyl moieties, respectively, and six alkoxy substituents were performed by combination of a zinc or nickel templated cyclotetramerization and cross-coupling palladium mediated methodologies. In a similar way, the 'push-pull' compounds 3a,b having a reversal substitution pattern, characterized by the presence of one electron-donor 4- (dimethylamino)phenylethynyl unit and six strong acceptor alkylsulfonyl substituents were prepared. The compounds show very large second-order nonlinear optical responses.

Full text of DOI:10.1021/jo991843f

J . Org. Chem. 2000, 65, 2733-2739
2733
Syn th esis of Novel P u sh -P u ll Un sym m etr ica lly Su bstitu ted
Alk yn yl P h th a locya n in es
Eva M. Maya, Concepcio´n Garc´ıa, Eva M. Garc´ıa-Frutos, Purificacio´n Va´zquez, and
Toma´s Torres*
Departamento de Quı´mica Orga´nica (C-I), Universidad Auto´noma de Madrid,
Cantoblanco 28049-Madrid, Spain
Received November 30, 1999
Two families of “push-pull” phthalocyanines 1-3 having an unusually strong dipole moment have
been prepared. The syntheses of unsymmetrically substituted phthalocyanines 1a ,b and 2 bearing
one or two electron-withdrawing 4-nitrophenylethynyl moieties, respectively, and six alkoxy
substituents were performed by combination of a zinc or nickel templated cyclotetramerization
and cross-coupling palladium mediated methodologies. In a similar way, the “push-pull” compounds
3a ,b having a reversal substitution pattern, characterized by the presence of one electron-donor
4-(dimethylamino)phenylethynyl unit and six strong acceptor alkylsulfonyl substituents were
prepared. The compounds show very large second-order nonlinear optical responses.
In tr od u ction
conjugation using double and triple bonds as linkers,8a,10
we describe the preparation of new “push-pull” phtha-
locyanines 1-3 and preliminary studies of their second-
order NLO properties. Taking into account that the
exploitation of phthalocyanines in nonlinear optics de-
mands good solubility, for example for the organization
of the molecules in thin films, the butoxy- and propyl-
sulfonyl groups provide these compounds with enough
solubility in organic solvents for this purpose. The new
phthalocyanines reported in this paper show the highest
dipolar moments and second-order nonlinear responses
described until now in the literature for unsymmetrically
substituted phthalocyanines.
Metallophthalocyanines (MPcs)1,2 are two-dimensional
18 π-electron conjugated systems, which have been
intensively investigated for many technological applica-
tions. Modifications of Pcs are usually made by incorpo-
rating a wide variety of central metal ions, by peripheral
substitution of the macrocycle,1,2 or by preparation of
analogues.3 Their chemical flexibility facilitates the
tailoring of their electrophysical parameters in a very
broad range.
It has been suggested that unsymmetrically substi-
tuted Pcs with suitable donor and acceptor groups should
exhibit second-order nonlinear optical (NLO) responses.4,5
Some research effort has been carried out in order to
study noncentrosymmetric peripherally substituted Pcs
for this particular purpose,6-8 but the synthetic challenge
of developing new Pc-based targets capable of displaying
efficient intramolecular charge-transfer remains open.9
In the present paper, and as a continuation of our
interest in the preparation of Pc systems with extended
Resu lts a n d Discu ssion
The preparation of the unsymmetrically substituted
Pcs 1a ,b bearing an electron-acceptor nitrophenylethynyl
moiety was attempted in two different ways.
Statistical templated condensation11 (Scheme 1) of 4,5-
* To whom correspondence should be addressed. Phone: (+34) 91
3974151; Fax: (+34) 91 3973966. E-mail: tomas.torres@uam.es.
(1) (a) Leznoff, C. C.; Lever, A. B. P. Phthalocyanines. Properties
and Applications; VCH Publishers (LSK) Ltd.: Cambridge, 1996, 1993,
1989; Vols. 1-4. (b) Hanack, M.; Heckmann, H.; Polley, R. Methods in
Organic Chemistry (Houben-Weyl); Schaumann, E., Ed.; Georg Thieme
Verlag: Stuttgart, 1998; Vol. E 9d, pp 717-833.
(2) (a) Mckeown, N. B. Phthalocyanines Materials, Synthesis, Struc-
ture and Function; Cambridge University Press: Cambridge, 1998. (b)
De la Torre, G.; Nicolau, M.; Torres, T. In Handbook of Advanced
Electronic and Photonic Materials; Nalwa, H. S., Ed.; J ohn Wiley &
Sons Ltd.: Chichester, in press.
(3) For Pc-related compounds with interesting electrical and non-
linear optical properties, see: (a) Keller, U.; Del Rey, B.; Rojo, G.;
Agullo´-Lo´pez, F.; Nonell, S.; Mart´ı, C.; Brasselet, S.; Ledoux, I.; Zyss,
J .; Torres, T. J . Am. Chem. Soc. 1998, 120, 12808-12817. (b) Ferna´n-
dez-La´zaro, F.; Torres, T.; Hauschel, B.; Hanack, M. Chem. Rev. 1998,
98, 563-575. (c) De la Torre, G.; Mart´ınez-D´ıaz, M. V.; Ashton, P.;
Torres, T. J . Org. Chem. 1998, 63, 8888-8893. (d) Claessens, C.;
Torres, T. Chem. Eur. J ., in press.
(4) (a) Li, D. A.; Ratner, M. A.; Marks, T. J . J . Am. Chem. Soc. 1988,
110, 1707-1715. (b) Li, D.; Marks, T. J .; Ratner, M. A. Chem. Phys.
Lett. 1986, 131, 370-375.
(5) For reviews on the NLO properties of Pcs, see: (a) Nalwa, H. S.;
Miyata, S. Nonlinear Optics of Organic Molecules and Polymers; CRC
Press: Boca Rato´n, FL 1997. (b) De la Torre, G.; Torres, T.; Agullo´-
Lo´pez, F. Adv. Mater. 1997, 9, 265-269. (c) De la Torre, G.; Va´zquez,
P.; Agullo´-Lo´pez, F.; Torres, T. J . Mater. Chem. 1998, 8, 1671-1683.
(6) (a) Liu, Y.; Xu, Y.; Zhu, D.; Wada, T.; Sasabe, H.; Liu, L.; Wang,
W. Thin Solid Films 1994, 244, 943-946. (b) Liu, Y.; Xu, Y.; Zhu, D.;
Wada, T.; Sasabe, H.; Zhao, X.; Xie, X. J . Phys. Chem. 1995, 99, 6957-
6960. (c) Liu, Y.; Xu, Y.; Zhu, D.; Zhao, X. Thin Solid Films 1996, 289,
282-286. (d) Liu, S. G.; Liu, Y.-Q.; Xu, Y.; Zhu, D.-B.; Yu, A.-C.; Zhao,
X.-S. Langmuir 1998, 14, 690-694.
(7) (a) D´ıaz-Garc´ıa, M. A.; Agullo´-Lo´pez, F.; Sastre, A.; Del Rey, B.;
Torres, T.; Dhenaut, C.; Ledoux, I.; Zyss, J . MCLC S&T, Sect. B:
Nonlinear Opt. 1996, 15, 251-254. (b) Sastre, A.; D´ıaz-Garc´ıa, M. A.;
Del Rey, B.; Dhenaut, C.; Zyss, J .; Ledoux, I.; Agullo´-Lo´pez, F.; Torres,
T. J . Phys. Chem. 1997, 101, 9773-9777.
(8) (a) Rojo, G.; De la Torre, G.; Garc´ıa-Ruiz, J .; Ledoux, I.; Zyss, J .;
Torres, T.; Agullo´-Lo´pez, F. Chem. Phys. 1999, 245, 27-34. (b) Tian,
M.; Wada, T.; Sasabe, H. J . Heterocyclic Chem. 1997, 34, 171-176. (c)
Tian, M.; Wada, T.; Kimura-Suda, H.; Sasabe, H. Mol. Cryst. Liq. Cryst.
1997, 294, 271-274. (d) Tian, M.; Wada, T.; Kimura-Suda, H.; Sasabe,
H. J . Mater. Chem. 1997, 7, 861-863.
(9) For an excellent example of design of noncentrosymmetric Pc-
systems for second harmonic generation see: Fox, J . M.; Katz, T. J .;
Elshocht, S. V.; Verbiest, T.; Kauranen, M.; Persoons, A.; Thongpan-
chang, T. T.; Krauss, T.; Brus, L. J . Am. Chem. Soc. 1999, 121, 3453-
3459.
(10) (a) Maya, E. M.; Va´zquez, P.; Torres,T. Chem. Eur. J . 1999, 5,
2004-2013. (b) Gonza´lez, A.; Va´zquez, P.; Torres, T. Tetrahedron Lett.
1999, 40, 3263-3266.
(11) (a) Vacus, J .; Memetzidis, G.; Doppelt, P.; Simon, J . J . Chem.
Soc., Chem. Commun. 1994, 697-698. (b) Chambrier, I.; Cook, M. J .;
Russell, D. A.; Synthesis 1995, 1283-1286.
10.1021/jo991843f CCC: $19.00 © 2000 American Chemical Society
Published on Web 04/13/2000

2734 J . Org. Chem., Vol. 65, No. 9, 2000
Maya et al.
Ch a r t 1
Sch em e 1. Syn th esis of
Nitr op h en yleth yn ylp h th a locya n in e Meta l(II)
Com p lexes 1a ,b by Sta tistica l Con d en sa tion
To overcome these problems a second strategy was
followed for the preparation of 1a ,b (Scheme 2). Statisti-
cal condensation of 4 and phthalonitrile 615 in the
presence of the appropriate metal salt yielded compounds
7a ,b in moderate yield (13-19%). The protecting group
was then removed16 to afford alkynyl compounds 8a ,b.
Further reaction of 8a ,b with p-iodonitrobenzene in the
presence of a catalyst formed in situ by adding triphenyl-
arsine to tris(dibenzylidenacetone)dipalladium(0) [Pd2-
(dba)3],17 in order to prevent the homocoupling reaction
of the dialkynyl compound, yielded 1a ,b in good yield.
Figure 1 shows the UV-visible spectra of the hexabu-
toxy(nitrophenylethynyl)phthalocyaninato 1a and its
precursor 8a . The optical characteristics of the new
conjugated system differs from that of unsymmetrical
parent terminal alkyne 8a . The Soret band is centered
at 357 nm for both compounds. However, while 8a shows
a single broad Q-band at 681 nm, the push-pull phtha-
locyanine 1a exhibits a remarkable split Q-band at 677
and 696 nm. The observed shifting to the red of the
Q-band can be attributed to the extended π-conjugation
of the system, as found previously by us in other
conjugated systems prepared.10a,18 Similar results were
obtained for compounds 1b and 8b.
The synthesis of compound 2 bearing two electron-
withdrawing (4-nitrophenyl)ethynyl substituents was
carried out starting from the diiodophthalocyanine 919
by cross-coupling with 4-ethynylnitrobenzene using bis-
[triphenylphosphine]palladium(II) dichloride [Pd(PPh3)2-
Cl2] as catalyst and an excess of potassium iodide20
(Scheme 3). LSIMS spectrum of 2 shows an isotopic
pattern at m/z 1299-1301 corresponding to the proto-
nated molecular ion. A singlet centered at 6.9 ppm in the
1H NMR spectrum identifies the aromatic protons of the
Pc-ring. The moderate solubility of compound 2 in organic
solvents, like in the case of Pcs 1 and 3, precludes the
registration of useful 13C NMR spectra.
dibutoxyphthalonitrile12 (4) and phthalonitrile 5, the
latter being prepared by palladium-mediated cross-
coupling of 4-iodophthalonitrile13 and 4-nitrophenyl-
ethyne,14 afforded a mixture of the corresponding octa-
butoxyphthalocyaninate metal(II) and the unsymmetrical
compound 1a or 1b. The zinc compound 1a could be
isolated with much difficulty by chromatography in low
yield (5%), whereas the separation of 1b from the
corresponding reaction mixture was not possible, due to
the strong tendency to aggregation of the corresponding
polyalkoxyphthalocyaninatos.
The UV/vis spectrum of compound 2 is depicted in
Figure 1. The optical features of this highly conjugated
(15) Maya, E. M.; Haisch. P.; Va´zquez, P.; Torres, T. Tetrahedron
1998, 54, 4397-4404.
(16) Ames, D. E.; Bull, D.; Takundwa, C. Synthesis 1981, 364-365.
(17) Wagner, R. W.; J ohnson, T. E.; Li, F.; Lindsey, J . S. J . Org.
Chem. 1995, 60, 5266-5273.
(12) (a) Wo¨hrle, D.; Schmidt, V. J . Chem. Soc., Dalton Trans. 1988,
549-554. (b) Kobayashi, N.; Opallo, M.; Osa, T. Heterocycles 1990, 30,
389-392.
(13) Marcuccio, S. M.; Svirskaya, P. I.; Greenberg, S.; Lever, A. B.
P.; Leznoff, C. C.; Tomer, K. B. Can J . Chem. 1985, 63, 3057-3069.
(14) Zhang, A. Y.; Wen, J . Synthesis 1990, 727-729.
(18) Maya, E. M.; Va´zquez, P.; Torres, T. Chem. Commun. 1997,
1175-1176.
(19) Garc´ıa-Frutos, E. M.; Ferna´ndez-La´zaro, F.; Torres, T. J . Org.
Chem., to be submitted.
(20) Powel, N. A.; Rychnovsky, S. D. Tetrahedron Lett. 1996, 37,
7901-7904.

Novel Push-Pull Alkynyl Phthalocyanines
J . Org. Chem., Vol. 65, No. 9, 2000 2735
Sch em e 2. Syn th esis of P h th a locya n in e Meta l(II) Com p lexes 1a ,b by a Cr oss-cou p lin g Meth od
diethynyl derivative 2 exhibits a strongly split Q-band
(672 and 713 nm), as well as a remarkable broadening
and red-shift of this absorption. The same effect has been
observed in alkynyl-linked Pc-dyads previously reported
by us10a in which an electronic connection between the
two Pc subunits has been clearly established.21 The red-
shifting has to be attributed to the enlargement of the
π-conjugated system being the splitting of the Q-band, a
consequence of the strong asymmetry of the molecule.
The preparation of “push-pull” compounds 3a ,b hav-
ing a reversal substitution pattern was also achieved
following two different pathways. The first one is depicted
F igu r e 1. Electronic spectra in CHCl3 of 1a (2.5 10-6 M) (solid
in Scheme 4 and it consists of the statistical reaction of
appropriately substituted phthalonitriles 11 and 12 in a
2:1 ratio in the presence of the corresponding zinc and
line), 2 (3.0 10-6 M) (dotted-dashed line), and 8a (6.2 10-6 M)
(dotted line).
nickel acetates. In the present case, a mixture of o-dichlo-
Sch em e 3. Syn th esis of
robenzene-DMF was used as solvent in order to prevent
the side reactions on the sulfonyl group which take place
under the presence of more nucleophilic solvents.22 In
these conditions, the corresponding octapropylsulfon-
ylphthalocyaninatos of zinc(II) and nickel(II) 13a ,b (not
represented) were obtained accompanying 3a and 3b,
respectively. The compounds were separated by column
chromatography. The starting material 11 was synthe-
sized in two steps, in good yield, starting from 4,5-
dichlorophthalonitrile23 by nucleophilic substitution with
propylthiol in the presence of K2CO3 to give 10, followed
by oxidation with H2O2 in acetic acid as indicated in
Scheme 4. The second precursor 12 was prepared from
4-(N,N-dimethylamino)phenylethyne24 by reaction with
4-iodophthalonitrile in the presence of bis[triphenylphos-
Bis(n itr op h en yleth yn yl)P h th a locya n in e Zin c(II)
Com p lex 2
(21) Maya, E. M.; Va´zquez,P.; Torres, T.; Gobi, L.; Diederich, F.; Pyo,
S.; Echegoyen, L. J . Org. Chem. 2000, 65, 823-830.
(22) Durst, T. Comprenhensive Chemistry; J ones, N., Ed.; University
of Sheffield: Sheffield, 1979.
(23) Wo¨hrle, D.; Eskes, M.; Shigehara, K.; Yamada, A. Synthesis
1993, 194-196.
(24) Rodr´ıguez, J . G.; Ramos, S.; Mart´ın-Villamil, R.; Fonseca, I.;
Albert, A. J . Chem. Soc., Perkin Trans. 1 1996, 541-543.
system differ remarkably from those of the related mono-
alkynyl-substituted species 1a (Figure 1). The Soret (B)
transition of 2 in the near UV-region of the spectrum
spans a wavelength range of 300-440 nm, similar to that
of compound 1a . However, while the monoalkynyl com-
pound 1a shows a split Q-band (677 and 696 nm), the

2736 J . Org. Chem., Vol. 65, No. 9, 2000
Maya et al.
Sch em e 4. Syn th esis of (d im eth yla m in op h en yl)Eth yn ylp h th a locya n in e Meta l(II) Com p lexes 3a ,b by
Sta tistica l Con d en sa tion
Sch em e 5. Syn th esis of (d im eth yla m in op h en yl)Eth yn ylp h th a locya n in e Meta l(II) Com p lexes 3a ,b by a
Cr oss-cou p lin g Meth od
phine]palladium(II) dichloride [Pd(PPh3)2Cl2] and cata-
lytic amounts of copper(I) iodide in good yield.
Compounds 3a ,b can also be obtained following the
pathway depicted in Scheme 5. Compound 11 and 4-io-
dophthalonitrile were reacted in a templated condensa-
tion reaction to afford a statistical mixture of compounds
from which the monoiodo derivatives 14a ,b could be
isolated by column chromatography. In this reaction
variable amounts of the corresponding octa(propylsul-
fonyl)phthalocyaninato metal(II) 13a ,b (not represented),
formed by cyclotetramerization of the major starting
material 11, were obtained. The amount of these and
other statistical distribution compounds accompanying
F igu r e 2. Electronic spectra in CHCl3 of: 3a (3.6 × 10-6 M)
14a ,b depends obviously on the ratio of the starting
(solid line), 3b (3.5 × 10-6 M) (thin line), 14a (6.7 × 10-6 M)
materials. Compounds 14a ,b were then reacted with
(dotted line), and 14b (7.0 × 10-6 M) (dashed line).
4-(N,N-dimethylamino)phenylethyne as described above
in the preparation of 12 to afford phthalocyanines 3a ,b
in good yield.
moments in the ground state were experimentally ob-
tained from capacitance measurements in chloroform
solutions by a classical Guggenheim method.25 HRS
experiments26,27 were performed by measuring the in-
tensity of the second-order scattered light on focusing an
intense laser beam on a chloroform solution. The mea-
surements were carried out at 1.064 µm which is directly
emitted by a nanosecond Q-switched Nd: YAG laser.
Both the permanent dipole moments µ and the âHRS
susceptibilities of the compounds are the highest reported
in the literature for unsymmetrical “push-pull” phthalo-
cyanines.5,8a Zinc derivatives 1a and 3a show higher µ
Figure 2 shows the UV/vis spectra of compound 3a and
its precursor 14a . The “push-pull” phthalocyanine 3a
shows a broad and not well-resolved split Q-band (686
and 711 nm). In this case the precursor 14a already
shows splitting of the Q-band. The enlargement of the
π-conjugated system is again responsible for the red-
shifting of the Q-band in 3a .
Similar results were obtained when comparing 3b and
14b. It is remarkable that the spectrum of the nickel
precursor 14b shows only one Q-band centered at 686
nm. The different behavior of 14a and 14b should be
attributable to the different kind of central metal.
Preliminary second-order NLO studies on phthalocya-
nines 1-3 have been carried out. The permanent dipole
(25) Guggenheim, E. A. Trans. Faraday Soc. 1949, 45, 714-723.
(26) Maker, P. D. Phys. Rev. A 1970, 1, 923-951.
(27) The studies are being carried out in the Laboratories of Prof.
F. Agullo´-Lo´pez (Madrid) and Prof. J . Zyss (Cachan, France).

Novel Push-Pull Alkynyl Phthalocyanines
J . Org. Chem., Vol. 65, No. 9, 2000 2737
chromatography on silica gel using a mixture of hexane-
dioxane (2:1) as eluent, to yield 34 mg (46%) of 2. Mp > 200
and â values than the corresponding nickel compounds
1b and 3b. Thus for example, compound 1a shows a
dipole moment of 39 D and a â value of 220 × 10-30 esu,
while the nickel compound 1b shows µ and â values of
28 D and 73 × 10-30 esu, respectively. Similar results
were obtained for compounds 3. The different â values
of compounds 1a and 1b seem to indicate that the central
metal could play an important role. Compound 2 contain-
ing two electron-withdrawing groups is less soluble in
chloroform than the structurally related compound 1a .
For these reason, the experimental dipole moment µ
could not be obtained with accuracy. The âHRS value for
1a can be estimated in ca. 500 × 10-30 esu, thus
indicating the importance of the substitution pattern. The
NLO properties of this new family of phthalocyanines and
other related compounds is being studied in detail.27
1
°C; H NMR (300 MHz, CDCl3) δ: 8.0-7.2 (m, 12H), 4.0-3.8
(m, 12H), 1.8 (m, 12H), 1.57 (m, 12H), 1.04 (m, 18H); FT-IR
(KBr) ν: 3104, 2207, 1637, 1600, 1385, 1342 cm-1; UV/vis
(CHCl3) λmax (log ꢀ): 713 (4.9), 672 (4.8), 610 (4.3), 361 nm (4.9);
MS-FAB (m-NBA) m/z (%): 1304-1298 (isotopic pattern) (100)
[(M + H)+], 1242-1245 (isotopic pattern) (16). Anal. Calcd for
C
72H70N10O10Zn‚H2O: C, 65.57; H, 5.50; N, 10.62. Found: C,
65.73; H, 5.67; N, 10.38.
23-[2-(4-(N,N-Dim et h yla m in o)p h en yl)et h yn yl]-2,3,9,-
10,16,17-h exa k is(p r op ylsu lfon yl)p h th a locya n in a to Zin c-
(II) or Nick el(II) (3a ,b ). Met h od
A (cr oss-cou p lin g
m eth od ): A mixture of 0.048 mmol of phthalocyaninatos 14a ,b
and 8 mg (0.057 mmol) of 4-(N,N-dimethylamino)phenyl-
ethyne24 was dissolved in freshly distilled and deaerated
diethylamine (for 14a ) or piperidine (for 14b) in the presence
of [PdCl2(PPh3)2] (6 mg, 0.008 mmol) and CuI (2 mg, 0.01
mmol). The mixture was stirred at room temperature under
argon atmosphere. The reaction was monitored by TLC until
the starting phthalocyanine had reacted. Then, the solvent was
removed under reduced pressure, and the residue was ex-
tracted with CH2Cl2 and washed with water. The phthalocya-
ninatos 3a ,b were purified by chromatography using a mixture
of CH2Cl2-MeOH (50:1) as eluent.
3a : Green solid. Reaction time: 4 h. Yield: 43 mg (67%).
Mp > 200 °C; 1H NMR (300 MHz, CDCl3) δ: 8.78 (s, 3H), 8.68
(s, 3H), 8.38 (s, 2H), 7.85 (broad signal, 2H), 5.95 (broad signal,
2H), 4.45 (m, 6H), 3.6 (m, 12H), 1.8 (m, 12H), 1.05 (2xt, 18H);
FT-IR (KBr) ν: 3440, 2960, 2510, 1290, 1085 cm-1; UV/vis
(CHCl3) λmax (log ꢀ): 711(5.3), 686 (5.3), 372 nm (5.1); MS-FAB
(m-NBA) m/z (%): 1359-1356 (isotopic pattern) (100) [(M +
H)+], 1146-1142 (isotopic pattern) (18) [(M - 2 × SO2C3H7)+].
Anal. Calcd for C60H61N9O12S6Zn‚3H2O: C, 51.10; H, 4.79; N,
8.94. Found: C, 51.50; H, 4.82; N, 8.60.
Exp er im en ta l Section
2,3,9,10,16,17-Hexabu toxy-23-[2-(4-n itr oph en yl)eth yn yl]-
p h th a locya n in a to Zin c(II) or Nick el(II) (1a ,b). Meth od
A (cr oss-cou p lin g m eth od ): A mixture of 0.048 mmol of 8a
or 8b and 4-iodonitrobenzene (14 mg, 0.058 mmol) was stirred
at room temperature in freshly distilled and deaerated tri-
ethylamine in the presence of [Pd2(dba)3] (6 mg, 0.006 mmol)
and AsPh3 (10 mg, 0.032 mmol) under argon atmosphere. The
reaction was monitored by TLC until all the starting material
had reacted. After the solvent was evaporated under reduced
pressure, the product was extracted with CH2Cl2 and washed
with water. After removing the organic solvent, the blue-green
solid obtained was purified by chromatography on silica gel,
using a mixture of CH2Cl2-MeOH (100:1).
1a : Reaction time: 20 h. Yield: 44 mg (80%). Mp > 200
°C; 1H NMR (300 MHz, TFA-d) δ: 8.7-8.1 (m, 13H), 4.45 (m,
12H), 2.0 (m, 12H), 1.65 (m, 12H), 1.0 (m, 18H); FT-IR (KBr)
ν: 3502, 2880, 1550, 1281, 1092 cm-1; UV/vis (CHCl3) λmax (log
ꢀ): 696 (5.4), 677 (5.4), 615 (4.8), 357 nm (5.2); MS-FAB (m-
NBA) m/z (%): 1157-1155 (isotopic pattern) (100) [(M + H)+],
1100-1098 (isotopic pattern) (22) [(M - C4H9)+]. Anal. Calcd
for C64H67N9O8Zn‚4H2O: C, 62.61; H, 6.16; N, 10.27. Found:
C, 62.95; H, 6.32; N, 9.91.
1b: Reaction time: 24 h. Yield: 10 mg (35%). Mp > 200
°C; 1H NMR (300 MHz, CDCl3) δ: 7.5 (broad signal, 13H), 4.4
(m, 12H), 2.12 (m, 12H), 1.45 (m, 12H), 0.8 (m, 18H); FT-IR
(KBr) ν: 3450, 2870, 1555, 1300, 1091 cm-1; UV/vis (CHCl3)
λmax (log ꢀ): 687 (4.9), 668 (4.9), 313 nm (4.8); MS-FAB (m-
NBA) m/z (%): 1150-1148 (isotopic pattern) (21) [(M + H)+],
881 (100). Anal. Calcd for C64H67N9O8Ni‚3H2O: C, 63.90; H,
6.12; N, 10.48. Found: C, 63.95; H, 6.02; N, 10.75.
Meth od B (sta tistica l m eth od ): A mixture of 4,5-dibu-
toxyphthalonitrile12 (4) (300 mg, 1.09 mmol) and phthalonitrile
5 (99 mg, 0.36 mmol) was heated at reflux in (dimethyl-
amino)ethanol (DMAE) (2 mL) under argon for 12 h in the
presence of zinc(II) chloride (48 mg, 0.36 mmol). After the
solvent was concentrated under reduced pressure, the solid
residue was extracted with CH2Cl2 and washed with water.
Compound 1a was isolated from the octabutoxyphthalocyani-
nato zinc(II) by 3-fold column chromatography on silica gel
using a mixture of hexane-THF (5:1) as eluent, to yield 14
mg (5%).
2,3,9,10,16,17-Hexa bu toxy-23,24-bis[2-(4-n itr op h en yl)-
eth yn yl]p h th a locya n in a to Zin c(II) (2). A mixture of bis-
[triphenylphosphine]palladium(II) dichloride [Pd(PPh3)2Cl2]
(4.2 mg, 2.94 mmol) and CuI (12.5 mg, 2.38 mmol) was added
to a solution of diiodophthalocyanine 919 (71.5 mg, 0.057 mmol)
and 4-nitroethynylbenzene (33 mg, 4.85 mmol) in freshly
distilled and deaerated DMF and triethylamine (1:5) (2 mL).
The reaction mixture was heated with stirring at 70 °C under
argon atmosphere for 10 min, and then potassium iodide (44
mg, 7.30 mmol) was added slowly.20 The mixture was left at
that temperature overnight. The solvent was removed under
reduced pressure, and the crude product was purified by
3b: Green solid. Reaction time: 12 h. Yield: 38 mg (60%).
Mp > 200 °C; H NMR (300 MHz, CDCl3) δ: 7.6 (s, 3H), 6.9
1
(s, 6H), 4.05 (m, 12H), 3.1 (m, 6H), 1.25 (m, 12H), 0.87 (m,
18H); FT-IR (KBr) ν: 3445, 2950, 2500, 1291, 1070 cm-1; UV/
vis (CHCl3) λmax (log ꢀ): 701(4.3), 677 (4.4), 345 nm (4.4); MS-
FAB (m-NBA) m/z (%): 1350 (25) [(M + H)+], 936 (100) [(M -
4 × SO2C3H7)+]. Anal. Calcd for C60H61N9O12S6Ni‚3H2O: C,
51.31; H, 4.34; N, 8.98. Found: C, 51.10; H, 4.63; N, 9.14.
Meth od B (sta tistica l m eth od ): A mixture of 4,5-bis-
(propylsulfonyl)phthalonitrile (11) (400 mg, 1.17 mmol) and
4-[2-(4-(N,N-dimethylamino)phenyl)ethynyl]pthalonitrile (12)
(159 mg, 0.58 mmol) was heated at 130 °C in a mixture of
o-dichlorobenzene-DMF (5:1) under argon for 6 h in the
presence of the corresponding metallic salt, zinc(II) acetate
dihydrate [Zn(OAc)22H2O], or nickel(II) acetate tetrahydrate
[Ni(OAc)24H2O], (0.58 mmol). After the solvent was concen-
trated under reduced pressure, the blue green solid was
extracted with CH2Cl2 and washed with water. Compound 3a
was isolated from the octapropylsulfonylphthalocyaninato zinc-
(II) by chromatography on silica gel using a mixture of CHCl3
and ethanol (400:1) as eluent, whereas for 3b a mixture of CH2-
Cl2-ethanol (40:1) was employed.
3a : Yield: (60 mg, 8%).
3b: Yield: (47 mg, 8%).
4-[2-(4-Nitr op h en yl)eth yn yl]p h th a lon itr ile (5). A mix-
ture of 4-nitrophenylethyne14 (0.68 g, 4.6 mmol) and 4-iodo-
phthalonitrile13 (1 g, 3.9 mmol) was dissolved in freshly
distilled diethylamine (20 mL) and dry THF (10 mL) in the
presence of [Pd(PPh3)2Cl2] (28 mg, 0.039 mmol) and CuI (3.7
mg, 0.019 mmol). The reaction mixture was stirred for 12 h
under argon atmosphere. Then, the solvent was removed under
reduced pressure and the crude reaction mixture diluted with
CH2Cl2 and washed with water. The brown solid obtained was
purified by chromatography on silica gel using a mixture of
toluene and hexane (3:1) as eluent, to yield 0.67 g (63%) of 5
1
as orange solid. Mp 214-215 °C; H NMR (200 MHz, CDCl3)
δ: 8.3 (d, J ) 6.4 Hz, 2H), 7.98 (s, 1H), 7.85 (s, 2H), 7.7 (d, J
) 6.4 Hz, 2H); 13C NMR (50 MHz, CDCl3) δ: 147.5, 136.5,
136.4, 134.3, 133.1, 127.6, 126.9, 123.9, 115.6, 115.5, 115.1,
114.6, 92.9, 90.5; MS (EI, 70 eV) m/z (%): 273 (100) [M+], 226

2738 J . Org. Chem., Vol. 65, No. 9, 2000
Maya et al.
(22) [(M - NO2)+]. Anal. Calcd for C16H7N3O2: C, 70.33; H,
4,5-Bis(p r op ylsu lfon yl)p h th a lon itr ile (11). Five grams
(18 mmol) of 10 was stirred with acetic acid (100 mL) under
reflux. Then, 83 mL of H2O2 was added slowly, and the mixture
reaction was stirred at this temperature for 3 h. The yellow
solution was poured into water, and the white solid obtained
was filtered and washed with water. The solid was dried under
2.58; N, 15.38. Found: C, 69.97; H, 2.80; N, 14.98.
2,3,9,10,16,17-H exa b u t oxy-23-(3-h yd r oxy-3-m et h yl-1-
bu tyn yl)p h th a locya n in a to Zin c(II) or Nick el(II) (7a ,b).
A mixture of 4,5-dibutoxyphthalonitrile (4)12 (500 mg, 1.83
mmol) and 4-(3-hydroxy-3-methyl-1-butynyl)phthalonitrile
(6)15 (128 mg, 0.61 mmol) was heated at reflux in (dimethyl-
amino)ethanol (DMAE) (2 mL) under argon for 12 h in the
presence of the corresponding metallic salt (MCl2) (0.61 mmol).
After the solvent was concentrated under reduced pressure,
the blue green solid was extracted with CH2Cl2 and washed
with water. Compound 7a was isolated from the octabutoxy-
phthalocyaninato zinc(II) by chromatography on silica gel
using a mixture of CH2Cl2 and ethanol (30:1) as eluent,
whereas for 7b a mixture of CH2Cl2-2-propanol (400:1) was
employed.
7a : Green solid. Yield: 86 mg (13%). Mp > 200 °C; 1H NMR
(300 MHz, CDCl3) δ: 8.78 (s, 6H), 7.58 and 7.4 (2 × s, 3H),
4.67 and 4.43 (2 × m, 13H), 2.89 (m, 12H), 1.91 (m, 12H), 1.3
(m, 24H); 13C NMR (75 MHz, TFA-d) δ: 153.7, 150.5, 125.0,
118.7, 115.7, 115.0, 114.3, 111.2, 110.5, 107.5, 106.8, 97.5, 69.8,
29.7, 17.7, 11.05, 10.6; UV/vis (CHCl3) λmax (log ꢀ): 685 (5.1),
613 (4.4), 356 nm (5.0); MS-FAB (m-NBA) m/z (%): 1093-1091
(isotopic pattern) (100) [(M + H)+], 1034 (32) [(M - C4H9)+].
Anal. Calcd for C61H70N8O7Zn‚3H2O: C, 63.89; H, 6.68; N, 9.77.
Found: C, 63.58; H, 6.54; N, 9.61.
7b: Green solid. Yield: 130 mg (19%). Mp > 200 °C; 1H
NMR (300 MHz, CDCl3) δ: 7.6 and 6.06 (2 × s, 9H), 4.1 (m,
12H), 3.49 (m, 1H), 1.85 (m, 12H), 1.61 (m, 12H), 1.25 (m, 24H);
UV/vis (CHCl3) λmax (log ꢀ): 676 (5.2), 610 (4.7), 291 nm (5.4);
MS-FAB (m-NBA) m/z (%): 1087-1085 (isotopic pattern) (100)
[(M + H)+]. Anal. Calcd for C61H70N8O7Ni‚4H2O: C, 63.27; H,
6.79; N, 9.68. Found: C, 63.62; H, 6.93; N, 9.65.
2,3,9,10,16,17-H e xa b u t oxy-23-e t h yn ylp h t h a locya n i-
n a to Zin c(II) or Nick el(II) (8a ,b). A mixture of phthalocya-
ninatos (7a or 7b) (0.091 mmol) and powdered sodium hy-
droxide (4 mg, 0.091 mmol) in dry toluene was heated at reflux
until the starting phthalocyaninate had reacted. After the
solvent was removed under reduced pressure, the residue was
extracted with CH2Cl2 and washed with water. The crude
reaction was purified by column chromatography on silica gel
using a mixture of CH2Cl2-MeOH (100:1) as eluent.
8a : Reaction time: 4 h. Yield: 74 mg (79%). Mp > 200 °C;
1H NMR (300 MHz, TFA-d) δ: 9.13, 8.69, 8.29 (3 × m, 9H),
4.65 (m, 12H), 3.7 (m, 1H), 2.28 (m, 12H), 1.89 (m, 12H), 1.29
(m, 18H); FT-IR (KBr) ν: 3500, 2885, 1280, 1092 cm-1; UV/
vis (CHCl3) λmax (log ꢀ): 681 (4.9), 613 (4.3), 357 nm (4.7); MS-
FAB (m-NBA) m/z (%): 1035-1033 (isotopic pattern) (100) [(M
+ H)+], 977 (25) [(M - C4H9)+]. Anal. Calcd for C58H64N8O6-
Zn‚H2O: C, 66.13; H, 6.32; N, 10.64. Found: C, 65.87; H, 6.72;
N, 10.33.
8b: Reaction time: 2 h. Yield: 37 mg (38%). Mp > 200 °C;
1H NMR (300 MHz, CDCl3) δ: 7.55, 7.13, 7.11 (3 × m, 9H),
4.12 (m, 12H), 3.37 (m, 1H), 2.17 and 1.81 (m, 12H), 1.58 (m,
12H), 0.87 (m, 18H); FT-IR (KBr) ν: 3500, 2880, 1282, 1091
cm-1; UV/vis (CHCl3) λmax (log ꢀ): 672 (5.4), 620 (5.0), 291 nm
(5.4); MS-FAB (m-NBA) m/z (%): 1027 (100) [(M + H)+]. Anal.
Calcd for C58H64N8O6Ni‚3H2O: C, 64.38; H, 6.00; N, 10.36.
Found: C, 64.65; H, 6.12; N, 10.38.
4,5-Bis(p r op ylth io)p h th a lon itr ile (10). A mixture of 4,5-
dichlorophthalonitrile23 (5 g, 25 mmol) and K2CO3 (10.31 g,
75 mmol) was stirred in dimethylacetamide (DMAC) (132 mL)
at room temperature and under argon atmosphere for 10 min.
Then, 5 mL (55 mmol) of propanothiol was added, and the
mixture was stirred at 80 °C for 12 h. The crude reaction was
diluted with CH2Cl2, and the organic phase was washed
several times with H2O. Removal of the solvent at reduced
pressure yielded 10.76 g (52%) as white solid. Mp 141-142
°C; 1H NMR (200 MHz, CDCl3) δ: 7.44 (s, 2H), 3.01 (t, J ) 6.8
Hz, 4H), 1.79 (m, 4H), 1.09 (t, J ) 6.8 Hz, 6H); 13C NMR (50
MHz, CDCl3) δ: 114.1, 128.1, 115.6, 110.9, 34.5, 21.5, 13.5;
MS (EI 70 eV) m/z (%): 276 (100) [M+]. Anal. Calcd for
1
vacuum with P2O5. Yield: 2.44 g (40%). Mp 189-190 °C; H
NMR (200 MHz, CDCl3) δ: 8.68 (s, 2H), 3.65 (m, 4H), 1.8 (m,
4H), 1.07 (t, J ) 7.3 Hz, 6H); 13C NMR (50 MHz, CDCl3) δ:
144.4, 137.5, 121.1, 113.0, 58.7, 16.3, 12.9; MS (EI 70 eV) m/z
(%): 339 (10) [M+], 325 (100) [(M - CH3)+]. Anal. Calcd for
C14H16N2O4S2: C, 49.40; H, 4.74; N, 8.24. Found: C, 49.09; H,
4.72; N, 7.93.
4-[2-(4-(N,N-Dim et h yla m in o)p h en yl)et h yn yl]p t h a lo-
n itr ile (12). A mixture of 4-(N,N-dimethylamino)phenyl-
ethyne24 (0.66 g, 4.6 mmol) and 4-iodophthalonitrile13 (1 g, 3.9
mmol) was dissolved in freshly distilled diethylamine (16 mL)
and THF (20 mL) in the presence of [Pd(PPh3)2Cl2] (28 mg,
0.039 mmol) and CuI (3.7 mg, 0.019 mmol). The reaction
mixture was stirred for 12 h under argon atmosphere. Then,
the solvent was removed under reduced pressure, and the
crude reaction mixture was diluted with CH2Cl2 and washed
with water. The orange solid obtained was purified by chro-
matography on silica gel using a mixture of hexane-CH2Cl2
(3:2) as eluent, to yield 0.79 g (75%) of 12. Mp 165-168 °C
(decomposition); 1H NMR (200 MHz, CDCl3) δ: 7.84 and 7.73
(2 × s, 3H), 7.42 (dd, J ) 2.09 Hz, J ′ ) 6.89 Hz, 2H), 6.66 (dd,
J ) 2.09 Hz, J ′ ) 6.89 Hz, 2H), 3.03 (s, 6H); 13C NMR (50
MHz, DMSO-d6) δ: 150.8, 135.4, 135.2, 134.1, 133.1, 129.1,
115.9, 115.2, 111.7, 106.4, 98.4; MS (EI 70 eV) m/z (%): 271
(100) [M+]. Anal. Calcd for C18H13N3‚H2O: C, 75.00; H, 5.20;
N, 14.58. Found: C, 75.15; H, 5.05; N, 14.24.
23-Iod o-2,3,9,10,16,17-h exa k is(p r op ylsu lfon yl)p h th a lo-
cya n in a to Zin c(II) (14a ). A mixture of 4,5-bis(propylsulfon-
yl)phthalonitrile (11) (500 mg, 1.47 mmol) and 4-iodophtha-
lonitrile13 (116 mg, 0.49 mmol) was heated at reflux in (2 mL)
of a mixture of o-dichlorobenzene-DMF (3:1) under argon for
12 h in the presence of zinc acetate dihydrate [Zn(OAc)2‚2H2O]
(0.49 mmol). After the solvent was concentrated under reduced
pressure, the residue was extracted with CH2Cl2 and washed
with water. The phthalocyaninato 14a was isolated from a
mixture of Pcs by chromatography on silica gel using a mixture
of CH2Cl2-MeOH (30:1). The triiodobis(propylsulfonyl)phth-
alocyaninato zinc(II) (15a ) was obtained as the first eluted
compound, the phthalocyaninato 14a was the second one, and
finally 2,3,9,10,16,17,23,24-octakis(propylsulfonyl)phthalo-
cyaninato zinc(II) (13a ) was eluted.
14a : Yield: 86 mg (13%). Mp > 200 °C; 1H NMR (300 MHz,
TFA-d) δ: 10.5, 10.25, 9.65, 9.25 (4 × m, 6H), 8.85 (d, 2H), 8.6
(s, 1H), 4.15 (m, 8H), 3.8 (m, 4H), 2.2 and 1.95 (2xm, 12H),
1.35 (m, 12H), 1.05, (m, 6H); FT-IR (KBr) ν: 3450, 2966, 2927,
1291, 1142, 1083 cm-1; UV/vis (CHCl3) λmax (log ꢀ): 703 (5.2),
669 (5.1), 643 (sh) (4.6), 609 (sh) (4.4), 368 nm (4.8); MS-FAB
(m-NBA) m/z (%): 1340-1338 (isotopic pattern) (100) [(M +
H)+], 1129-1125 (isotopic pattern) (18) [(M - 2 × SO2C3H7)+].
Anal. Calcd for C50H51N8IO12S6Zn‚4H2O: C, 42.56; H, 4.21; N,
7.94. Found: C, 42.22; H, 4.26; N, 7.67.
15a : Yield: 60 mg (10%). Mp > 200 °C; 1H NMR (300 MHz,
CDCl3) δ: 7.81 (s, 2H), 7.7-7.4 (m, 9H), 3.89 (t, 4H), 1.73
(broad signal, 4H), 1.24 (s, 6H); UV/vis (CHCl3) λmax (log ꢀ):
689 (5.2), 678 (5.1), 643 (4.7), 361 nm (4.9); MS (FAB, m-NBA)
m/z (%): 1169-1165 (isotopic pattern) (100) [(M + H)+], 956-
952 (isotopic pattern) (29) [(M - 2 × SO2C3H7)+]. Anal. Calcd
for
C38H25N8I3O4S2Zn‚3H2O: C, 37.35; H, 2.56; N, 9.17.
Found: C, 37.11; H, 2.70; N, 9.28.
13a : Yield: 50 mg (7%). Mp > 200 °C; 1H NMR (300 MHz,
TFA-d) δ: 10.4 (s, 8H), 3.88 (broad signal, 16H), 1.9 (m, 16H),
1.25 (s, 24H); FT-IR (KBr) ν: 3329, 2971, 1292, 1144, 1102
cm-1; UV/vis (CHCl3) λmax (log ꢀ): 686 (5.6), 617 (sh) (4.7), 376
nm (4.9); MS-FAB (m-NBA) m/z (%): 1427-1425 (isotopic
pattern) (100) [(M + H)+], 1213-1211 (isotopic pattern) (15)
[(M - 2 × SO2C3H7)+]. Anal. Calcd for C56H64N8O16S8Zn‚H2O:
C, 46.55; H, 4.76; N, 7.75. Found: C, 46.88; H, 4.60; N, 7.38.
23-Iod o-2,3,9,10,16,17-h exa k is(p r op ylsu lfon yl)p h th a lo-
cya n in a to Nick el(II) (14b). A mixture of 4,5-bis(propylsul-
C
14H16N2S2: C, 60.83; H, 5.83; N, 10.13. Found: C, 60.67; H,
5.85; N, 9.94.

Novel Push-Pull Alkynyl Phthalocyanines
J . Org. Chem., Vol. 65, No. 9, 2000 2739
fonyl)phthalonitrile (11) (500 mg, 1.47 mmol) and 4-iodo-
phthalonitrile (116 mg, 0.49 mmol) was heated at reflux in (2
mL) of a mixture of o-dichlorobenzene-DMF (3:1) in the
presence of nickel(II) acetate tetrahydrate [Ni(OAc)2‚4H2O] (98
mg, 0.49 mmol) under argon for 12 h. After the solvent was
concentrated under reduced pressure, the blue residue was
extracted with CH2Cl2 and washed with water. The phthalo-
cyaninato 14b was isolated from 2,3,9,10,16,17,23,24-octakis-
(propylsulfonyl)phthalocyaninato nickel(II) (13b) by a double
column chromatography on silica gel using a mixture of CH2-
Cl2-2-propanol (100:1), and CH2Cl2-hexane-dioxane (2:1:1),
as eluents.
13b: Yield: 84 mg (15%). Mp > 200 °C; 1H NMR (300 MHz,
CDCl3) δ: 10.5 (broad signal, 8H), 4.0 (m, 16H), 2.14 (m, 16H),
1.2 (m, 24H); UV/vis (CHCl3) λmax (log ꢀ): 674 (5.2), 607 (sh)
(4.4), 348 nm (4.7); MS-FAB (m-NBA) m/z (%): 1421-1419
(isotopic pattern) (100) [(M + H)+].
Ack n ow led gm en t. This work was supported by
CICYT and Comunidad de Madrid (Spain) through
grants MAT-99-0180 and 07N/0020/98, respectively. A
Graduated Research Fellowship of the Comunidad de
Madrid to Eva Mar´ıa Maya is gratefully acknowledged.
14b: Blue solid. Yield: 54 mg (8%). Mp > 200 °C; 1H NMR
(300 MHz, CDCl3) δ: 8.8 (broad signal, 4H), 7.0-6.5 (broad
signal, 5H), 3.67 (m, 12H), 1.44 (m, 12H), 1.19 (m, 18H); FT-
IR (KBr) ν: 3441, 2969, 2935, 1295, 1108, 1085 cm-1; UV/vis
(CHCl3) λmax (log ꢀ): 686 (5.6), 617 (sh) (4.7), 376 nm (4.9); MS-
FAB (m-NBA) m/z (%): 1335-1333 (isotopic pattern) (100) [(M
+ H)+]. Anal. Calcd for C50H51N8IO12S6Ni‚4H2O: C, 42.71; H,
4.23; N, 7.97. Found: C, 42.89; H, 4.36; N, 7.76.
Su p p or t in g In for m a t ion Ava ila b le: 1H and 13C NMR
data. This material is available free of charge via the Internet
at http://pubs.acs.org.
J O991843F