Observations regarding the crystal structures of non-halogenated phenoxyboronsubphthalocyanines having para substituents on the phenoxy group

Article abstract of DOI:10.1039/c0ce00599a

We report the synthesis and systematic description of a series of five para-substituted phenoxy-BsubPcs including their characterization in the crystal state. The nature of the substituents on the phenoxy molecular fragment was chosen so as to vary both t

Full text of DOI:10.1039/c0ce00599a

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Observations regarding the crystal structures of non-halogenated
phenoxyboronsubphthalocyanines having para substituents on the phenoxy
group†
a
Andrew S. Paton, Graham E. Morse, Alan J. Lough and Timothy P. Bender
a
b
ab
*
Received 1st September 2010, Accepted 10th September 2010
DOI: 10.1039/c0ce00599a
We report the synthesis and systematic description of a series of five para-substituted phenoxy-BsubPcs
including their characterization in the crystal state. The nature of the substituents on the phenoxy
molecular fragment was chosen so as to vary both the size and electronegativity: specifically with
increasingly bulky para-alkyl groups from hydrogen to tert-octyl and a single electronegative substitute
(F). Examination of the arrangement of the phenoxy-BsubPcs within single crystals allows us to place
each into one of the two categories. The first, which contains all but one of the derivatives, has
a repeating motif which is made up of dimers of the BsubPc molecular fragments. The second,
containing only the derivative possessing the large tert-octyl substituent, is characterized by the
formation of ribbons instead of dimers of the BsubPc fragment. Regardless of motif the arrangement of
the BsubPc molecular fragments was found to be convace–concave.
ligand into its unique non-planar C3v symmetric bowl shape (1,
Introduction
Fig. 1a). As a result of its shape and the lone ability of boron to
chelate its formation, Cl-BsubPc has been described as an
anomalous member of the broader phthalocyanine (Pc) family.
While Pcs possess absorption maxima at wavelengths greater
than 700 nm, Cl-BsubPc has a blue shifted maximum absorption
wavelength of 560 nm.3 The reduced conjugation length and
bowl shape of Cl-BsubPc provide it with unique optoelectronic
properties compared with the broader Pc class of compounds
and researchers have studied it for applications in non-linear
optics,4 organic light emitting diodes (OLEDs),5 organic field
effect transistors (OTFTs),6 and solar cells.7 Recently our group
has become similarly interested in the solid-state application of
BsubPc and more specifically its phenoxy derivatives. One can
assume that the nature of both the BsubPc moiety and the phe-
noxy substituent will play a role in its solid state intermolecular
arrangement. While the chemistry to produce phenoxy-BsubPc
derivatives is known8 we were unable to locate a comprehensive
study of the intermolecular arrangement of phenoxy-BsubPcs in
the solid state. Nor are there any crystal structures deposited in
the CCD of non-halogenated phenoxy-BsubPcs. However
a report detailing the arrangement in the solid state of a series of
alkoxy-BsubPc derivatives does not appear in the literature.9
In this paper, we report the systematic study of a series of five
non-halogenated phenoxy BsubPcs all made by the reaction of
Cl-BsubPc (1, Scheme 1) with a series of structurally similar
phenols having a variety of substituents in the para-position. The
substituents were chosen so as to vary in size and electronega-
tivity and the single crystal structures of each of the phenoxy-
BsubPcs were determined.
Chloro boron subphthalocyanine (Cl-BsubPc), first synthesized
in 1972,1 is a non-planar, aromatic metal–organic hybrid mole-
cule consisting of a heterocyclic organic moiety comprising three
repeating isoindoline units the sum of which ligates a B(III) atom.
A chlorine atom in the axial position completes the Cl-BsubPc
structure. The related phthalocyanines (Pcs) have four repeating
isoindoline units and have been shown to coordinate to a large
variety of metals across the periodic table.2 The smaller subPc
ligand is only known to chelate boron and in doing so stresses the
Fig. 1 Illustration of Cl-BsubPc (1) reproduced from single crystal X-
ray diffraction data:1b (a) top view and (b) side view (cyan—carbon;
blue—nitrogen; green—chlorine and yellow—boron).
aDepartment of Chemical Engineering and Applied Chemistry, University
of Toronto, 200 College Street, Toronto, Ontario, Canada M5S 3E5.
E-mail: tim.bender@utoronto.ca
bDepartment of Chemistry, University of Toronto, 80 St George St,
Toronto, Ontario, Canada M5S 3H6
† Electronic supplementary information (ESI) available: Displacement
ellipsoid plots, bond distances and selected interaction distances for
Results and discussion
compounds 2a–e, as well as
a schematic of the Kauffman
Cl-BsubPc (1, Scheme 1) was required as a starting material for
our study; however, no commercial source of sufficiently high
purity could be identified. Therefore, we synthesized Cl-BsubPc
chromatography column along with the instructions on its use. CCDC
reference numbers 783165–783169. For ESI and crystallographic data
in CIF or other electronic format see DOI: 10.1039/c0ce00599a
914 | CrystEngComm, 2011, 13, 914–919
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of the fluorine atom was deliberate due to its electronegativity
and its similar atomic size to hydrogen.
The method used to obtain the phenoxy derivatives is a robust,
general method and was used for all five derivatives (2a–e). The
method of Claessens et al.8a was adapted as follows: Cl-BsubPc (1)
was heated in toluene with 5 molar equivalents of the appropriate
phenol derivative for between 8 and 72 hours (time varied for
complete conversion as monitored by HPLC). After the synthesis
was complete, the toluene was evaporated and the residual phenol
was removed on standard basic alumina in a Kauffman column
chromatography apparatus10 using dichloromethane as the
eluent. The excess phenol remained adsorbed to the alumina and
the product eluted through the alumina with hot dichloro-
methane. On removal of the dichloromethane, product in excess
of 99% purity was obtained in all cases. In the case of tert-octyl-
phenol (compound 2d), in our first attempt the entire mass of
residual phenol could not be adsorbed onto the alumina and an
aqueous/organic workup was needed in order to remove the excess
tert-octylphenol prior to Kauffman column chromatography.
Compounds 2a,8a 2b8b and 2c8c have been previously described in
the literature with reported yields after purification of 18%, 79%
and 58%. They have been obtained using a variety of synthetic and
purification methods including crystallization,8a column chro-
matography8b and preparative thin layer chromatography.8c
Using the combination of the synthetic method of Claessens
et al.8a and Kauffman column chromatography11 we have ach-
ieved yields of 95%, 79% and 81% for compounds 2a, 2b and 2c
respectively all with purities exceeding 99%. While in two of the
three cases our yields are markedly higher, we wish to highlight
Kauffman column chromatography as a facile method to obtain
high purity phenoxy-BsubPcs regardless of whether base extrac-
tion is performed first.
Scheme 1 Synthesis of phenoxy-BsubPcs used in this study.
We were able to form diffractable single crystals of compounds
2a–e by slow diffusion crystallization using benzene (good
solvent) and heptane (diffusing solvent). Classic crystallization
was also successful in obtaining single crystals suitable for
diffraction of compounds 2a–c. We also obtained single crystals
through simple solvent evaporation. In each case we confirmed
the structure of the single crystals was equivalent by X-ray
diffraction. However, we only report in detail the single crystals
obtained by vapour diffusion as conversely, only diffusion
crystallization was capable of producing high quality single
crystals of compounds 2d and 2e. Depictions of the unit cell and
a summary of structural parameters (lengths and angles) for
single crystals of compounds 2a–e formed through vapour
diffusion are given in the ESI† accompanying this article.
In order to shape the discussion of the crystal structures of
compounds 2a–e, we wish to outline some terminology and will
use the single crystal structure of Cl-BsubPc (1, illustrated in
Fig. 1) as a reference point.1b With regard to the unique bowl
shaped structure of the BsubPc molecular fragment, we will
denote the face of the BsubPc containing the axial chlorine atom
as the convex face and the opposite the concave face, consistent
with previously established terminology.9a
in our own laboratory using a method adapted from Zyskowski
and Kennedy.10 We found that the crude synthesis proceeded as
described but a simple Soxhlet extraction with methanol after
synthesis was sufficient to purify the resulting Cl-BsubPc past
99%. We have since repeated this procedure in excess of 15 times
with consistent results.
Subsequently, a series of five phenoxy derivatized BsubPc (2a–
e, Scheme 1) were synthesized from Cl-BsubPc (1) in a single
additional step. With regard to compounds 2a–e, phenoxy
substituents were targeted so as to vary the size and the elec-
tronegativity of the substituent in the para-position of the phe-
noxy moiety. Progressing from a hydrogen atom (2a) to a methyl
(2b) to a tert-butyl (2c) allowed a large increase in the bulkiness
of the substituent while keeping the orientation the same (para)
and the number of degrees of freedom the same, thus main-
taining the rotational symmetry of the phenoxy group as a whole.
Further increasing the size of the hydrocarbon substituent from
tert-butyl (2c) to tert-octyl (2d) not only increases the number of
hydrocarbon atoms and the associated bulk but also the number
of degrees of freedom due to rotational variations inherent in the
tert-octyl group—although this increase is minimized for the
relatively large number of carbons (eight) due to the structure of
the tert-octyl group. Variations in electronegativity of the
substituent were also made, progressing from phenoxy (2a) to 4-
fluorophenoxy (2e) while again maintaining symmetry. The use
On examination of the organization within the single crystal of
compounds 2a–e we have found that this series of compounds
can be subdivided into two categories. The first, represented by
compounds 2a–c and 2e, have a consistent motif present within
their crystal structures which consists of two BsubPc molecular
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fragments associated in a dimeric concaved-to-concaved orien-
tation. This motif is illustrated in Fig. 2 for compound 2a where
the associated pair is illustrated in orange (the same illustrations
for compounds 2b, 2c and 2e appear in the ESI† accompanying
this article, Fig. S7†). The presence of this dimer motif within the
single crystal is independent of both the steric bulk of the
substituent on the phenoxy group (as indicated by examination
and comparison of compounds 2a–c) as well as the electroneg-
ativity of the substituent (as indicated by examination and
comparison of compound 2a versus 2e). Also illustrated in Fig. 2
is the spatial relationship between each dimer unit. In each case
the phenoxy molecular fragment of one molecule is in close
proximity to the convex face of a neighbouring BsubPc. The
spatial arrangement of the phenoxy fragment with companion
phenoxy BsubPc fragments does change on increasing steric bulk
of the substituent for compounds 2a–c. This qualitative obser-
vation will be quantified below. This tendency to form dimeric
pairs of BsubPc molecular fragments is not seen in other BsubPc
derivatives. For example phenoxy-perfluorinated-BsubPc,12a
halo-perfluorinated-BsubPc,12b,c and some alkoxy-BsubPcs12d,e
tend to arrange in a similar concave–convex motif.
Fig. 3 Illustration of the extended crystal structure of compound 2d.
BsubPc ribbons shown in orange, an additional tert-octylphenoxy-
BsubPc shown in violet and benzene shown in cyan. Hydrogens are
omitted for clarity. Disorder of benzene and tert-octyl substituents are
also omitted for clarity.
Phenoxy-BsubPc 2d contains the sizable tert-octyl substituent,
which has a large number of carbons but a relatively low number
of degrees of freedom (compared to n-octyl, for example) and is
the sole occupant of the second category. Compound 2d crys-
molecular features that were common to each structure were
noted. They are schematically illustrated in Fig. 4. The noted
values included the distance between one BsubPc unit and its
nearest neighbour in both the dimer or ribbon concave–concave
arrangement (d1) and to next nearest BsubPc unit in another
dimer or ribbon (d2): so as to quantify the concave–concave
association. For the same reason, the ring centroid to ring
centroid (Cg–Cg) distances of the associated BsubPc fragments
were also noted. Additionally, in order to quantify any bond
angle strain or bond elongation between the BsubPc and phe-
noxy molecular fragments resulting from crystallization, we
noted the angle of the phenoxy fragment relative to the BsubPc
fragment (as indicated by the B–O–C angle) and the lengths of
the boron–oxygen bond (B–O bond length) and oxygen–carbon
bond (O–C bond length). The noted values are summarized in
Table 1.
tallized into
a distinctly different arrangement than did
compounds 2a–c and 2e. The BsubPc fragments are no longer
associated in discrete pairs, but rather are arranged in one
dimensional ribbons. Each ribbon consists of one BsubPc frag-
ment associating with two additional BsubPc fragments in
a concave–concave–concave arrangement, illustrated in Fig. 3.
These one dimensional ribbons are further arranged within
a second dimension and form a plane permeating throughout the
crystal. This plane of BsubPc fragments is entirely separated by
another plane comprising the tert-octylphenoxy fragments and
associated solvent molecules (benzene). The solvent molecules
are not present in discrete locations within the crystal, rather
disordered through this plane and there are tert-octylphenoxy
fragments inserted into the plane from each side. There is also
observed disorder amongst the tert-octyl substituents themselves.
This arrangement is very similar to the one which has been
observed for an alkylphenyl substituted BsubPc although in this
case there was no inclusion of solvent or disorder present.13a It
can also be found in at least one alkoxy-BsubPc.13b
What immediately stands out is that the distance between two
BsubPc units in a dimer (for compounds 2a–c and 2e) or ribbon
(for compound 2d) arrangement does not change along the series
In order to attempt to quantify the changes in crystal structure
of all BsubPc derivatives in this study, certain inter- and intra-
Fig. 2 Illustrations of the extended crystal structure of exemplary
compound 2a: (a) ‘front’ view and (b) ‘side’ view (rotated 90ꢀ from front
view). BsubPc dimers shown in orange and neighbouring BsubPc shown
in violet. Hydrogens are omitted for clarity.
Fig. 4 Schematic representation of the compared quantities of the single
crystal X-ray determined structures of compounds shown in Scheme 1.
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Table 1 Selected metrics of the crystal structures of Cl-BsubPc (1) and phenoxy-BsubPcs (2a–e)
a
#
B–B distance, d1/A B–B distance, d2/A B–O–C angle/ꢀ B–O bond length/A O–C bond length/A Cg–Cg distance/A Space group
˚ ˚ ˚ ˚ ˚
11b 8.82
2a 8.26
2b 8.39
2c 8.78
2d 8.83
2e 8.18
10.30
5.58
5.59
8.61
12.01
5.55
—
—
—
—
3.674(1)
3.6045(9)
3.548(1)
3.691(1)
3.694(1)
Orthorhombic (Pnma
ꢀ
)
115.5(1)
115.6(1)
118.9(2)
129.1(2)
115.2(2)
1.443(2)
1.436(2)
1.437(3)
1.436(3)
1.447(3)
1.379(2)
1.386(2)
1.387(2)
1.368(2)
1.383(2)
Triclinic (P1)
ꢀ
Triclinic (P1)
ꢀ
Triclinic (P1)
Monoclinic (P21/c)
ꢀ
Triclinic (P1)
a
Ring centroid to ring centroid distance.
˚
˚
of compounds 2a–e—at approximately 8.83 A to 8.18 A. This is
further supported by the ring centroid to ring centroid distances
between the pairs of BsubPc fragments, which were fairly
within the molecule while preserving the dimer or ribbon motif
(in the crystal structure of compound 2d for example). The
preferential formation of dimers of the BsubPc molecular frag-
ment has not been previously observed in the crystal structure of
either alkoxy-BsubPcs12d,e or perfluorinated-BsubPc12a deriva-
tives, while the ribbon motif has been previously seen.13a,b We
hope an enhanced understanding of the solid state structure of
phenoxy-BsubPc derivatives will aid other research groups as
these compounds are applied to (for example) optical and elec-
tronic devices.
˚
constant, from 3.55 A to 3.69 A.
˚
As the substituent in the para-position of the phenoxy group
was increased in size from a hydrogen atom (2a) to a methyl
group (2b), no change in the separation between two dimers
occurred, as indicated by the B–B bond distance (d2) remaining
˚
constant at about 5.58 A to 5.59 A. A more significant increase to
˚
8.61 A was seen when the substituent was changed to a tert-butyl
˚
group in 2c, and the tert-octyl substituent group of 2d showed
˚
a d2 distance of 12.01 A, an increase of 2.15 times from 2a. A
Experimental
significant increase in the angle of the B–O–C bond with the
increase of the size of the substituent accompanied the increase in
d2 distance. As the bulkiness of the substituent group was raised
(2a–d), the bond connecting the phenoxy to the BsubPc,
increasing in angle from 115ꢀ for 2a and 2b to 119ꢀ for 2c and
finally 129ꢀ for compound 2d. For reference, using a simple semi-
empirical RM1 model, the B–O–C angle from a single isolated
molecule of each of the compounds 2a–e was calculated. The
calculated angles ranged from 115ꢀ to 116ꢀ therefore placing the
large increase to 129ꢀ for compound 2d in context. The distortion
of the B–O–C bond angle is not accompanied by a lengthening of
the associated bond lengths (B–O or O–C). If the B–O–C bond
angle distorts to such a great extent, this suggests that amongst
this series of phenoxy-BsubPcs the formation of closely associ-
ated dimers or ribbons of BsubPc fragments arranged in
a concave–concave fashion occurs even at the energetic expense
of bond angle distortions present within the remainder of the
molecule. Finally, the bond distances (d1 and d2) and bond angles
(B–O–C) were nearly identical and the space group was the same
for compound 2e as for compound 2a indicating the presence of
an electronegative fluorine atom had little effect on the crystal
structure.
Materials
Phthalonitrile and 4-fluorophenol were purchased from TCI
Company Ltd. (Portland, Oregon) and used as received. Boron
trichloride (BCl3) 1.0 M solution in heptane, phenol, p-cresol, 4-
tert-butylphenol and 4-tert-octylphenol were obtained from
Sigma Aldrich (Mississauga, Ontario, Canada) and used without
further purification. Other common solvents, reagents and
standard basic alumina (300 mesh) were purchased from Cale-
don Laboratories (Caledon, Ontario, Canada) and used as
received.
Methods
X-Ray diffraction results were analyzed using PLATON 40M-
version 25080914 for bond angles and lengths, and crystal
packing images were generated using Mercury version 2.2.15 All
crystal structures were collected using a Nonius KappaCCD
diffractometer equipped with an Oxford Cryostream variable
temperature apparatus. All nuclear magnetic resonance (NMR)
spectra were acquired on a Varian Mercury 400 MHz system in
deuterated chloroform with 0.05% (v/v) tetramethylsilane (TMS)
as a 1H NMR reference purchased from Cambridge Isotope
Laboratories and used as received. All ultraviolet-visible (UV-
Vis) spectroscopy was performed using PerkinElmer Lambda 25
in a PerkinElmer quartz cuvette with 10.00 mm path length.
The reaction progress was monitored using a Waters 2695 high
pressure liquid chromatography (HPLC) separation module with
a Waters 2998 photodiode array. A Waters 150 mm reverse phase
Sunfireꢀ C18 5 mm column was used with HPLC grade aceto-
nitrile (ACN, 1.2 mL minÀ1 isocratic) purchased from Caledon
Laboratories as the eluent.
Conclusions
We synthesized, purified, and obtained single crystals of a series
of five phenoxy-BsubPc derivatives. We have analyzed the single
crystals by X-ray diffraction and made observations on the
similarities and differences in their crystal structures. We have
been able to classify each derivative into one of the two categories
depending on the nature of its repeating motif: either the
formation of dimers or ribbons of the BsubPc moieties within the
crystal structure arranged between their respective concave faces.
As the size of the substituent on the phenoxy ring is increased we
have measured an associated B–O–C bond angle distortion
Cl-BsubPc10 and phenoxy-BsubPc derivatives 2a,9b 2b9d and
2c9e have been previously described in the literature. In the case of
the synthesis of compounds 2a–c our synthetic methods are
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higher yielding and we wish to highlight the use of Kauffman
chromatography11 as a facile and high yielding method for the
purification of these compounds to >99% purity.
Kauffman column purification, the excess 4-tert-octylphenol was
removed by dissolving the product in toluene (300 mL) and
extracting with 3.0 M KOH in distilled water (3 Â 300 mL).
Removal of the toluene and purification by Kauffman column as
above yielded compound 2d (0.453 g, 58%). dH(400 MHz,
CDCl3, Me4Si) 0.56–0.58 (9H, s), 1.11–1.14 (6H, s), 1.48–1.49
(2H, s), 5.29–5.32 (2H, d), 6.71–6.74 (2H, d), 7.87–7.92 (6H, m),
8.81–8.86 (6H, m); lmax(CHCl3)/nm 563.
Chloro boron subphthalocyanine (Cl-BsubPc, 1). Compound 1
was synthesized by adapting a previously published procedure.10
Phthalonitrile (5.32 g, 0.0415 mol) was dissolved with stirring in
1,2-dichlorobenzene (220 mL) in a round bottomed flask fitted
with a short path distillation column and placed, under
a constant flow of argon gas towards the short path distillation
column. To this solution BCl3 (100 mL of 1.0 M solution (0.1
mol) in heptane) was added in a single portion. On gradual
heating the heptane was distilled off. When distillation was
complete the reaction heated at reflux for an additional
1.5 hours. After cooling, the solvent was removed by rotary
evaporation. The resulting crude product was extracted with hot
methanol in a Soxhlet extraction apparatus for 8 hours. The
resulting golden-brown powder was then rinsed with diethyl
ether and dried in the vacuum oven yielding compound 1 (3.76 g,
63%). Purity by HPLC (99.5%, max plot). dH(400 MHz, CDCl3,
Me4Si) 7.95–7.97 (6H, m), 8.90–8.92 (6H, m); lmax(CHCl3)/nm
564.
4-Fluorophenoxyboronsubphthalocyanine (2e). Compound 2e
was synthesized as for 2a except 4-fluorophenol (0.729 g, 0.0065
mol) was used instead of phenol, yielding compound 2e (0.486 g,
74%). dH(400 MHz, CDCl3, Me4Si) 5.32–5.35 (2H, m), 6.40–6.45
(2H, t), 7.91–7.93 (6H, m), 8.84–8.87 (6H, m); lmax(CHCl3)/nm
563.
Preparation of single crystals. All crystals used for X-ray
diffraction were prepared through vapour diffusion using
benzene as the solvent and heptane as the diffusing solvent. All
samples (0.050 g) were dissolved in benzene (5 mL) and sealed in
an airtight jar with heptane (150 mL). Single crystals of high
quality suitable for X-ray diffraction were obtained within 1–2
weeks. All crystallographic information can be found in the
ESI†.
The phenoxy-BsubPc derivative was synthesized by a method
adapted from Claessens et al.8
Phenoxyboronsubphthalocyanine (2a)9b. Cl-BsubPc (1, 0.56 g,
0.0013 mol) was mixed with phenol (0.615 g, 0.0065 mol) in
toluene (10 mL) in a cylindrical vessel fitted with a reflux
condenser and argon inlet. The mixture was stirred and heated at
reflux under a constant pressure of argon for 8 hours. Reaction
was determined complete via HPLC by the absence of 1. The
solvent was evaporated under rotary evaporation. The crude
product purified on a Kauffman column using standard basic
alumina (300 mesh) as the adsorbent and dichloromethane as the
eluent. The product elutes from the Kauffman column while the
excess phenol remains adsorbed. The dichloromethane was then
removed under reduced pressure yielding a dark pink/magenta
powder of compound 2a (0.609 g, 95%). dH(400 MHz, CDCl3,
Me4Si) 5.37–5.41 (2H, d), 6.59–6.64 (1H, t), 6.72–6.78 (2H, t),
7.88–7.94 (6H, m), 8.83–8.88 (6H, m); lmax(CHCl3)/nm 563.
Similarly for other phenoxy-BsubPcs:
Acknowledgements
We thank Hatch Limited (Mississauga, Ontario, Canada) for
their endowed scholarship to Andrew S. Paton. We also thank
the Ontario Centres of Excellence (Ontario, Canada), the
Canadian Foundation for Innovation (CFI) and the Natural
Sciences and Engineering Research Council (NSERC) of Canada
for their financial support.
Notes and references
1 (a) A. Meller and A. Ossko, Monatsh. Chem., 1972, 103, 150; (b)
H. Kietaibl, Monatsh. Chem., 1974, 105, 405–418.
2 C. C. Leznoff and A. B. P. Lever, in Phthalocyanines: Properties and
Applications, Wiley Interscience, 1997, vol. 1–4.
ꢁ
3 G. Martın, G. Rojo, F. Agullo-Lopez, V. R. Ferro, J. M. G. de la
Vega, M. V. Martınez-Dıaz, T. Torres, I. Ledoux and J. J. Zyss,
ꢁ
ꢁ
ꢁ
ꢁ
J. Phys. Chem. B, 2002, 106, 13139–13145.
ꢁ
ꢁ
ꢁ
ꢁ
4 C. G. Claessens, D. Gonzalez-Rodrıguez, T. Torres, F. Agullo-Lopez,
I. Ledoux, J. Zyss, V. R. Ferro and J. M. G. de la Vega, J. Phys.
Chem. B, 2005, 109, 3800–3806.
4-Methylphenoxyboronsubphthalocyanine (2b)9d. Compound
2b was synthesized as for 2a except p-cresol (4-methylphenol,
0.707 g, 0.0065 mol) was used in place of phenol, yielding
compound 2b (0.605 g, 79%). dH(400 MHz, CDCl3, Me4Si) 2.01–
2.03 (3H, s), 5.27–5.31 (2H, d), 6.51–6.55 (2H, d), 7.88–7.93 (6H,
m), 8.82–8.88 (6H, m); lmax(CHCl3)/nm 563.
ꢁ
5 D. D. Dıaz, H. J. Bolink, L. Cappelli, C. G. Claessens, E. Coronado
and T. Torres, Tetrahedron Lett., 2007, 48, 4657–4660.
6 (a) K. L. Mutolo, E. I. Mayo, B. P. Rand, S. R. Forrest and
M. E. Thompson, J. Am. Chem. Soc., 2006, 128, 8108–8109; (b)
H. Kumar, P. Kumar, R. Bhardwaj, G. D. Sharma, S. Chand,
S. C. Jain and V. Kumar, J. Phys. D: Appl. Phys., 2009, 42, 015103;
(c) H. Gommans, D. Cheyns, T. Aernouts, C. Girotto,
J. Poortmans and P. Heremans, Adv. Funct. Mater., 2007, 17, 2653–
2658.
7 (a) T. Yasuda and T. Tsutsui, Mol. Cryst. Liq. Cryst., 2007, 462, 3–9;
(b) H. Gommans, T. Aernouts, B. Verreet, P. Heremans, A. Medina,
C. G. Claessens and T. Torres, Adv. Funct. Mater., 2009, 19, 3435–
3439.
8 (a) C. G. Claessens, D. Gonzalez-Rodrıguez, B. del Rey, T. Torres,
G. Mark, H.-P. Schuchmann, C. von Sonntag, J. G. MacDonald
and R. S. Nohr, Eur. J. Org. Chem., 2003, 2547–2551; (b)
K. Adachi and H. Watarai, Chem.–Eur. J., 2006, 12(16), 4249–4260;
(c) D. D. Dıaz, H. J. Bolink, L. Cappelli, C. G. Claessens,
E. Coronado and T. Torres, Tetrahedron Lett., 2007, 48, 4657–4660.
4-tert-Butylphenoxyboronsubphthalocyanine (2c)9e. Compound
2c was synthesized as for 2a except 4-tert-butylphenol (0.977 g,
0.0065 mol) was used instead of phenol yielding compound 2c
(0.571 g, 81%). dH(400 MHz, CDCl3, Me4Si) 1.07 (9H, s), 5.28–
5.30 (2H, d), 6.73–6.75 (2H, d), 7.89–7.92 (6H, m), 8.84–8.86
(6H, m); lmax(CHCl3)/nm 563.
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4-tert-Octylphenoxyboronsubphthalocyanine (2d). Compound
2d was synthesized as for 2a except 4-tert-octylphenol (1.34 g,
0.0065 mol) was used instead of phenol. In this case, before
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9 (a) C. G. Claessens, D. Gonzalez-Rodrıguez, B. del Rey and
T. Torres, Chem. Rev., 2002, 102, 835–853. See specifically section
V.A.1. p. 847; (b) K. Kasuga, T. Idehara, M. Handa, Y. Ueda,
T. Fujiwara and K. Isa, Bull. Chem. Soc. Jpn., 1996, 69(9), 2559–
A. Medina, D. Gonzalez-Rodrıguez, E. Gutierrez-Puebla,
A. Monge, I. Alkorta, J. Elguero and T. Torres, Chem.–Eur. J.,
2008, 14, 1342–1350; (d) Y. Inokuma, J. H. Kwon, T. K. Ahn,
M. C. Yoo, D. Kim and A. Osuka, Angew. Chem., Int. Ed., 2006,
45, 961. CCDC reference PEFVUS; (e) See ref. 12d. CCDC
reference PEFWAZ.
€
€
€
2563; (c) R. Potz, M. Goldner, H. Huckstadt, U. Cornelissen,
A. Tutaß and H. Homborg, Z. Anorg. Allg. Chem., 2000, 626(2),
588–596.
13 (a) F. Camerel, G. Ulrich, P. Retailleau and R. Zieseel, Angew. Chem.,
Int. Ed., 2008, 47, 8876–8880; (b) M. K. Engel, J. Yao, H. Maki,
H. Takeuchi, H. Yonehara and C. Pac, Report Kawamura Institute
of Chem. Res., 1997, vol. 9, p. 53. CCDC reference UCIJOF01.
14 A. L. Spek, Acta Crystallogr., Sect. D: Biol. Crystallogr., 2009, 65,
148–155.
15 C. F. Macrae, I. J. Bruno, J. A. Chisholm, P. R. Edgington,
P. McCabe, E. Pidcock, L. Rodriguez-Monge, R. Taylor, J. van
de Streek and P. A. Wood, J. Appl. Crystallogr., 2008, 41, 466–
470.
10 C. D. Zyskowski and V. O. Kennedy, J. Porphyrins Phthalocyanines,
2000, 4, 707–712.
11 (a) J. M. Kauffman and C. O. Bjorkman, J. Chem. Educ., 1976, 53(1),
33; (b) K. Chatterjee, D. Holmes Parker, P. Wurz, K. R. Lykke,
D. M. Gruen and L. M. Stock, J. Org. Chem., 1992, 57, 3253–3254.
12 (a) C. G. Claessens and T. Torres, Angew. Chem., Int. Ed., 2002, 41,
2561; (b) T. Fukuda, J. R. Stork, R. J. Potucek, M. M. Olmstead,
B. C. Noll, N. Kobayashi and W. S. Durfee, Angew. Chem., Int.
ꢁ
Ed., 2002, 41, 2565; (c) M. S. Rodrıguez-Morgade, C. G. Claessens,
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