Synthesis of supramolecular fullerene-porphyrin-Cu(phen) 2-ferrocene architectures. A heteroleptic approach towards tetrads

Article abstract of DOI:10.1039/b614111k

Four supramolecular fullerene-porphyrin-Cu(phen)₂-ferrocene architectures were accessed by a twofold coordination strategy. At first, the phenanthroline-linked zinc porphyrins 1-4, conceived as supramolecular synthons, were combined with a ferr

Full text of DOI:10.1039/b614111k

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Synthesis of supramolecular fullerene–porphyrin–Cu(phen)2–ferrocene
architectures. A heteroleptic approach towards tetrads†
Michael Schmittel,*a Ravuri S. K. Kishorea and Jan W. Batsb
Received 28th September 2006, Accepted 25th October 2006
First published as an Advance Article on the web 16th November 2006
DOI: 10.1039/b614111k
Four supramolecular fullerene–porphyrin–Cu(phen)2–ferrocene architectures were accessed by a
twofold coordination strategy. At first, the phenanthroline-linked zinc porphyrins 1–4, conceived as
supramolecular synthons, were combined with a ferrocene module, 3,8-(diferrocenylethynyl)-
phenanthroline (5), by a Cu(I)-mediated heteroleptic bisphenanthroline complexation (HETPHEN)
protocol to furnish the porphyrin–Cu(phen)2–ferrocene aggregates 6–9. Subsequently, the fullerene
module 10 was incorporated by axial pyridyl coordination to the zinc porphyrin, affording 11–14. Their
suitability as tetrads was interrogated using electrochemical and photophysical data.
very few reports of supramolecular triads,9 and none of tetrads,
are known. Invariably, in the fullerene–porphyrin–ferrocene triads
Introduction
known so far9 there is only one non-covalent binding motif
present, and either the fullerene or the ferrocene is covalently
bound to the porphyrin. A supramolecular triad/tetrad where
both the ferrocene and the fullerene subunits are bound solely
by non-covalent interactions has been difficult to access. In the
present study, we demonstrate how a combination of two orthog-
onal binding modes – involving (i) Cu(I)-mediated heteroleptic bis-
phenanthroline complexation and (ii) axial binding of pyridine to
zinc porphyrin – is used effectively to obtain four supramolecular
fullerene–porphyrin–Cu(phen)2–ferrocene aggregates, as a proof
of principle for the heteroleptic construction of tetrads. The
Cu(phen)2 complex, apart from playing a structural role as a non-
covalent binding unit, is known to efficiently mediate electron
transfer between Zn(II) and Au(III) porphyrins, as reported by
Sauvage,10 and is also known to be involved in photoinduced eT
processes with the C60 moiety.11
The conversion of solar into chemical energy is probably the most
important and consequential step occurring in the photosynthetic
reaction centre in plants.1 In purple photosynthetic bacteria for
instance, efficient light harvesting and excitation energy transfer
(EET) funnels solar energy from the photosystems LH2 and
LH1 to the special pair bacteriochlorophyll dimer (Bchl2).1 The
subsequent cascade of very fast electron transfer (eT) steps
•
•
produces a charge-separated (CS) state Bchl2 + Qa − (quinone) over
a fairly large distance.2 Charge recombination (CR) is effectively
avoided until the hole and electron are separated by a membrane.
Major efforts have been made in past decades towards mim-
icking this process and in developing artificial photosynthetic
systems.3,4 An important class of compounds showing long-lived
CS states are the fullerene-porphyrin-ferrocene triads, tetrads and
pentads.5 In particular, highly efficient photosynthetic electron
transfer has been realised by Fukuzumi, Guldi, Imahori, Ito and
colleagues6 in ferrocene–zinc porphyrin–C60 triads, in which the
relatively long-lived CS state (up to 16 ls) could be produced
with an extremely high quantum yield (nearly unity). They also
reported a ferrocene–zinc porphyrin trimer–fullerene pentad,7
which exhibited not only the longest lifetime (0.53 s in PhCN
at 163 K) of a CS state, but also an extremely high CS efficiency
(83%), comparable to the eT properties of bacteriochlorophyll
Results and discussion
The strategy to the supramolecular aggregates involves three
steps: (i) synthesis of phenanthroline-linked porphyrins 1–4;
(ii) Cu(I)-driven heteroleptic bis-phenanthroline complexation of
1–4 with bis(ferrocenylethynyl)phenanthroline 5 to afford the
Cu(I)-mediated supramolecular porphyrin–Cu(phen)2–ferrocene
aggregates 6–9; and (iii) axial coordination of pyridyl fullerene
10 to 6–9 to furnish the supramolecular fullerene–porphyrin–
ferrocene systems 11–14.
•
dimer radical cation (Bchl2 +)–secondary quinone radical anion
•
(QB −) ion pair in the bacterial photosynthetic reaction centre.
However, while in the natural photosynthetic reaction centre the
eT process occurs along a supramolecular relay system in a protein
matrix, most of the above-mentioned reports represent covalent
systems. Construction of well defined structures bearing three or
more different functional photo/redox active units is tedious in a
dynamic supramolecular regime.4a,d,8 It is hence not surprising that
Synthesis of phenanthroline-appended porphyrins 1–4
Our strategy towards the synthesis of 1–4 was to attach
phenanthroline12 Phen1 to the iodophenyl groups in porphyrins
P1–P4 via a Sonogashira cross-coupling. Compounds 1 and 4
have already been reported by us elsewhere.13
In order to access the required phenanthroline–porphyrin
hybrids 1–4, the meso-iodophenyl zinc-porphyrins P1–P4 were
first synthesised based on strategies outlined by Lindsey et al.14
A subsequent Sonogashira reaction using Pd2(dba)3/AsPPh3 in
aCenter of Micro and Nanochemistry and Engineering, Organische Chemie
I, Universita¨t Siegen, Adolf-Reichwein-Str., D-57068, Siegen, Germany.
E-mail: schmittel@chemie.uni-siegen.de; Fax: +49 271 740 3270
bInstitut fu¨r Organische Chemie und Chemische Biologie, Johann Wolfgang
Goethe-Universita¨t, Marie-Curie-Strasse 11, D-60439, Frankfurt, Germany
† Electronic supplementary information (ESI) available: Fig. S1–S27,
Tables S1–S3, and crystal structure data for 5. See DOI: 10.1039/b614111k
78 | Org. Biomol. Chem., 2007, 5, 78–86
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Table 1 Absorption and emission maxima of 1–4
kabs a/nm
benzene or pyridine with triethylamine as a base allowed for
the cross-coupling between Phen1 and P1–P4, to furnish 1–4
(Scheme 1). Purification of 1–4 was realised by chromatography on
silica-gel followed by size-exclusion chromatography on bio-beads
in toluene.
kemb/nm
1
2
3
4
289, 421*, 512, 549, 588
289, 424*, 550, 590
289, 424*, 550, 591
289, 428*, 551, 590
599, 648
600, 648
602, 653
606, 652
a Measured in CH2Cl2. b Excited at the Soret (*) absorption maximum.
Fig. 1 Absorption spectra of 1–4 measured in CH2Cl2 normalised at the
Soret band.
Formation of porphyrin–Cu(phen)2–ferrocene aggregates by the
HETPHEN complexation strategy
Ligands 1–4 are supramolecular building blocks, which can be
utilised for the construction of porphyrin–Cu(phen)2–ferrocene
systems by a metal-driven heteroleptic complexation. As a proof of
concept, we have recently incorporated phenanthrolinyl porphyrin
1 into a multicomponent self-assembled stack.13b Along the same
lines, the tetrakis(bis-heteroleptic) supramolecular phenanthroline
complex 9 was realised starting from porphyrin 4 through
a Cu(I)-mediated approach.13a Accordingly, the supramolecu-
lar aggregates 6–8 (Chart 1) were prepared based on the
HETPHEN15 approach. For this purpose, compound 5 was syn-
thesised by a Sonogashira reaction of ferrocenylacetylene with 3,8-
dibromophenanthroline using [Pd(PPh3)2]Cl2/CuI and NHiPr2
(Scheme 2). Single crystals of 5 were obtained by slow diffusion
of hexane into a concentrated solution of 5 in chloroform. Fig. 2
displays the crystal structure of 5.
Scheme 1 Synthesis of phenanthroline–porphyrin hybrids 1–4.
Table S1 (see ESI†) displays the various NMR shifts of 1–4
measured in CD2Cl2. It was noticed that the Hb protons of the
pyrrole units of the porphyrin rings were split according to the
symmetry of the ligands. The distinct attachment in the meso
position of the porphyrin did, however, not entail tangible NMR
shift differences of the phenanthroline protons. The sole difference
noted was an upfield shift for the 4,7- and 5,6-protons on the
phenanthroline unit of 4, compared to their counterparts in 1, 2,
and 3.
Absorption spectroscopy (Table 1) showed an increasing
bathochromic shift of the Soret band from 1 to 4 relative to zinc
5,10,15,20-tetraphenylporphyrin (ZnTPP), i.e. with the growing
number of phenanthrolines at the periphery of the zinc porphyrin
core (Fig. 1). Also noticed was the predicted increase in the
absorption coefficient of the phenanthroline chromophore in
1–4 in the 250–350 nm region. The ligands displayed strong
fluorescence when excited at the Soret band.
Chart 1 Chemical representation of triads 6–9 and 6a.
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Formation of supramolecular
fullerene–porphyrin–Cu(phen)2–ferrocene systems
Reaction of 6–9 with 10 in CH2Cl2–CS2 (1 : 1) afforded 11–14
(Scheme 3, Chart 2). Their formation was readily detected by
UV-vis spectroscopy, because the Soret band of 11–14 displayed
a characteristic bathochromic shift from 420 nm to 430 nm. In
1
addition, characteristic shifts of various signals in the H NMR
were noticed. Notably, the Hb pyrrole signals of the porphyrin
were found to shift by ∼0.1 ppm upfield in all complexes. The
signal for the 3ꢀꢀ,5ꢀꢀ-mesitylene protons (C6H2Me3) experienced a
downfield shift from d 6.14 in 6–9 to d 6.21 in 11–14. (Table S2†).
Likewise, the signals corresponding to the ferrocene protons were
found shifted upfield by ∼0.1 ppm. This could arise due to the
proximity of the ferrocene to the fullerene subunit.
Scheme 2 Synthesis of diferrocenylethynylphenanthroline 5.
Fig. 2 Crystal structure of 5 (the non-H atoms are shown with 50%
probability ellipsoids).
X-Ray structure of 5‡. In the crystal structure of 5, the
phenanthroline unit showed a small distortion from planarity
with a mean deviation of the non-H atoms from the best plane
˚
of 0.048 A. Both ferrocenyl groups were found in approximately
eclipsed conformations. The angle between the best plane of
the phenanthroline group and the plane through C15–C17–C19
was found to be 13.4◦. Similarly, the angle between the best
plane of the phenanthroline group and the plane through C27–
C29–C31 was 14.8◦. The crystal structure revealed a chloroform
solvate being hydrogen-bonded to the two N atoms of the
phenanthroline group. The phenanthroline units formed stacks
along the b-direction (see ESI†). Neighbouring phenanthrolines
in the stacks showed partial overlapping p-systems in the region
C6–C7–C8–C9–C10–C11, with shortest interatomic p–p distances
Scheme 3 Reaction leading to formation of 11–14.
˚
being 3.27 and 3.35 A. In addition, the structure also indicated
The 1H NMR spectra of 6 and 11 are shown in Fig. 3. A distinct
upfield shift of the 3,5-pyridyl protons of 10 from d 7.76 ppm (as
free residue) to a broad singlet at d 6.44 (in 11) was noticed. The sig-
nals of the protons from the pyrrolidine ring fused to C60, at d 4.67
and 3.92, also experienced an upfield shift from d 5.02 and 4.32 in
10. Similar shifts were found in 12, 13 and 14. Due to the density of
methyl signals, the 2,6-pyridyl protons, known to shift drastically
upfield to the region d 0.5–2.0, were not readily discernible.
The sharp signals in the NMR spectra suggest that there is free
rotation about the various axes present in 11–14. In addition, no
broadening of any signals in 11–14 was observed compared to 6–
9. Presence of a single set of ferrocene signals was noticed in 11,
12 and 14, implying equal interaction of the fullerene with all the
ferrocene protons.
ESI-MS characterisation16 revealed molecular ion signals for
11–14, not unexpectedly accompanied by signals from 6–9. Within
the range of the instrument, isotopic splitting patterns were
obtained for 12–14, matching with those of the simulated spectra.
UV-Visible absorption titrations of 6–9 with 10 in
dichloroethane at 298 K exhibited spectral changes characteristic
of axial coordination of a pyridine ligand to a zinc porphyrin.17
The formation constants K for the porphyrin–fullerene conjugates
could be determined from the spectral data by SPECFIT.18 The
association constants are listed in Table 2. Notably, the association
two intermolecular C(ferrocenyl)–H–p(ferrocenyl) contacts and a
short intermolecular C(ferrocenyl)H–Cl interaction.
HETPHEN complexation15. Heteroleptic complexation of 1–4
with 5, furnishing complexes 6–9 in quantitative yield, was effected
using [Cu(CH3CN)4]PF6 in dichloromethane. The formation of
6–9 was clearly ascertained by observation of the molecular ion
peaks in the ESI-MS and by diagnostic NMR upfield shifts of the
3ꢀꢀ,5ꢀꢀ-protons of the mesityl groups of the phenanthroline units
(see ESI†).
‡ Crystal structure: a single crystal (a brown blade with dimensions
0.04 × 0.26 × 0.75 mm) was measured on a SIEMENS SMART 1 K
CCD diffractometer with Mo-Ka radiation at a temperature of about
158 K. Repeatedly measured reflections remained stable. An empirical
absorption correction with program SADABS22 gave a correction factor
between 0.804 and 0.952. 49 615 reflections measured, 9002 unique
reflections, R(I)int = 0.063. The structure was determined by direct methods
and refined by least-squares against all measured F2 values.23 The H atoms
were positioned geometrically and were constrained. C36H24Fe2N2·CHCl3,
M = 715.64, monoclinic, space group P21/c (no. 14), a = 22.770(3), b =
◦
3
˚
˚
7.5283(11), c = 19.570(3) A, b = 111.923(12) , V = 3112.1(8) A , Z =
4, Dx = 1.527 g cm−3, l = 1.22 mm−1, 397 refined parameters, R1(F)[I >
2r(I)] = 0.052, GOOF = 1.02, the final difference density was between
−3
˚
−1.12 and +1.07 e A near Cl atoms of the chloroform solvate group.
CCDC reference number 622456. For crystallographic data in CIF or
other electronic format see DOI: 10.1039/b614111k
80 | Org. Biomol. Chem., 2007, 5, 78–86
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Chart 2 Chemical representation of tetrads 11–14.
Fig. 3 Aromatic region in the 1H NMR spectra of 6 and 11. The solid black circles represent the shifts of the 3,5-H and the pyrrolidine protons.
constant for formation of 11–14 (from 6–9 and 10) is higher by
half an order of magnitude than that of ZnTPP and 10.
almost complete van der Waal’s contact between the ferrocene
and the fullerene unit, as reported earlier by D’Souza9a et al. for
other systems. This may explain the higher association constants
displayed by 11–14 and the upfield-shifted signals of the ferrocene
protons in the 1H NMR.
The molecular structure of aggregate 11 calculated at the
PM3 level in SPARTAN19 showed an edge-to-edge distance of
˚
4.1 A between the ferrocene and the C60 unit, indicative of an
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Table 2 E0–0 energies and association constants of zinc porphyrins with
10 calculated from UV-vis titration by SPECFIT
the individual redox steps, as analysed from the integrated areas
of the DPV curves, indicated that the first oxidation of the
porphyrin (P0/+) and that of Cu+/2+ overlapped at E = 0.41 VFc. This
assignment was confirmed by preparing 6a, the silver analog of 6,
containing an Ag(I) instead of the Cu(I) phenanthroline complex.
As for 6, the porphyrin E1/2 (P0/+) in 6a was located at E = 0.41 VFc.
Table 3 shows the redox potentials of 11–14. On the basis of
two criteria (peak separation Epa − Epc and ipa/ipc = 1) the redox
processes were found to be reversible. In contrast to systems 6–9,
theredoxwaves for Cu+/2+ andP0/+ in11–14onlypartlyoverlapped,
so that we could employ a peak deconvolution with PEAKFIT
for their analysis. The E1/2 (P0/+) of the porphyrin unit in 11–14
exhibited small, but uncharacteristic shifts when compared to 6–9,
while the reduction potential E1/2 (P0/−) revealed cathodic shifts of
0–70 mV. The porphyrin potentials E1/2 (P0/+) of 11–14 are higher
than that of ZnTPP·10 by 200 mV, mostly due to the electron-
withdrawing effect of the Cu+/2+ centres and to a lesser extent
because of the charged Fc•+ groups.
K/M−1
logb
E
0–0/eV
reference
ZnTPPa
11b
7.2 × 103
2.1 × 104
2.3 × 104
1.6 × 104
2.6 × 104
3.86 ( 0.38)
4.34 ( 0.05)
4.36 ( 0.02)
4.19 ( 0.07)
4.42 ( 0.03)
—
5d
1.96
1.96
1.96
1.96
this work
this work
this work
this work
12b
13b
14b
a Measured in ortho-dichlorobenzene at 298 K. b Measured in DCE at
298 K.
Compounds 11–14 are supramolecular aggregates built purely
by a supramolecular assembly protocol by applying two dynamic
non-interfering binding modes. Certainly, the heteroleptic Cu(I)–
bisphenanthroline complex is a dynamic yet robust (logb ∼9.7)
supramolecular motif, as we have recently shown by demonstrat-
ing the exchange of metal ions (Cu(I) vs. Ag(I)), as well as of
ligan◦ds.13 The latter was found to be completely arrested only at
−60 C. Axial binding of the pyridyl fullerene to zinc porphyrin
(logK ∼4.3) is comparatively more dynamic. This is evidenced by
Due to the spatial arrangement and electrochemical data of
11–14 we expect that upon photochemical excitation of the por-
•
•
phyrin unit a PET process will generate C60 −–Por +–Cu(phen)2 –
+
•
2+
Fc, which will undergo further CS to C60 −–Por–Cu(phen)2
–
1
broadened signals of the pyridyl protons in the H NMR of 11–
•
•
Fc and finally to C60 −–Por–Cu(phen)2 –Fc +. Hence, the present
+
14 at room temperature. However, an earlier study by Imamura20
◦
system should operate as a A–D–D–D tetrad, with the CS from
stated that below −40 C the dynamic nature of this system was
•
•
•
C60 −–Por +–Cu(phen)2 –Fc to C60 −–Por–Cu(phen)22+–Fc having
almost no driving force. A caveat of the present discussion is
that the redox data in Table 3 do not precisely reflect the redox
situation in the photochemically triggered tetrads. Obviously,
the PET process will be initiated with the ferrocene units being
uncharged and the copper being singly-charged, while the data for
P0/+ recorded in Table 3 are influenced by the oxidised ferrocene
and the doubly-charged copper units.
+
arrested, as seen from the sharpening of the signals of the pyridyl
protons in the 1H NMR.
Electrochemical studies
The electrochemical properties of complexes 11–14 were investi-
gated along with those of 1–9 (Table 3 and Table S3†). The redox
potentials were measured by differential pulse voltammetry (DPV)
and cyclic voltammetry in dichloroethane. The intactness of the
supramolecule in the presence of electrolyte NBu4PF6 under the
DPV and CV conditions was proven by absorption spectroscopy.
Redox data of 6–9 (Table 3) were measured in dichloroethane
by differential pulse voltammetry (DPV). It was observed that
Conclusions
We have successfully established a protocol to obtain dynamic
supramolecular aggregates based on two orthogonal coordinative
binding motifs. The successful introduction of a Cu(phen)2
redox unit into the tetrad system should facilitate stepwise
charge separation, as has been noticed previously with other
supramolecular CS systems.10,11,21 Moreover, the present self-
assembly approach leaves a lot of room for further fine-tuning
the redox potentials of P+/2+, P0/+, Cu+/2+ and ferrocene (Fc0/+
)
in 6–9 were not influenced by the number of phenanthrolines
at the porphyrin periphery. In contrast, the porphyrin reduction
potential (P0/−) exhibited an anodic shift of ∼70 mV while going
from 6 to 9 (Table 3). The number of electrons transferred in
Table 3 Redox potentials of 6–9 and 11–14
E1/2 vs. Fc a
0/−
−/2−
P+/2+
P0/+, Cu+/2+
Fc0/+
C60
C60
P0/−
HOMO–LUMO/eVb
6
6a
7
8
9
11
12
13
14
0.74
0.74
0.77
0.74
0.77
0.85
0.83
0.77
0.81
0.41, 0.41
0.41
0.21
0.21
0.20
0.21
0.20
0.21d
0.21
0.20
0.19
—
—
—
—
—
−1.06
−1.04
−1.08
−1.04
—
—
—
—
−1.91
—
—
—
—
—
0.41, 0.41
0.41, 0.41
0.41, 0.41
0.37, 0.30c
0.42, 0.36c
0.39, 0.33c
0.40, 0.28c
−1.86
−1.86
−1.84
−1.98
−1.88
−1.88
−1.85
—
—
−1.47
−1.44
−1.50
−1.44
1.27
1.25
1.28
1.23
a Determined by DPV in dichloroethane with NBu4PF6 as electrolyte, and measured against an Ag wire as a quasi-reference electrode and dimethylferrocene
as internal standard at 100 mV s−1. Potentials are referenced against the more common ferrocene redox couple. b Determined from the redox potentials
0/−
Fc0/+ − C60
.
c Deconvolution allowed to separate the overlapping waves of the P0/+ and Cu+/2+ redox processes. d Obtained by deconvolution.
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of the electronic properties of triads and tetrads, e.g. using other
spacers in between the coordination motifs, installing different
terminal redox relays and even modulating the redox properties
of the intermediate copper–bisphenanthroline linkage. Further
investigations on these supramolecular tetrads are underway.
(m, 4 H, 5,6-H), 7.59 (d, J = 8 Hz, 2 H, 8-H), 7.55 (d, J = 8 Hz,
ꢀꢀꢀ ꢀꢀꢀ
ꢀꢀ ꢀꢀ
ꢀ
4 H, Ar-Ha,Ha ) 7.31 (s, 4 H, 3 ,5 -H), 7.00 (s, 4 H, 3 ,5 -H), 2.63
(s, 6 H, 8ꢀꢀꢀ-H), 2.57 (s, 12 H, 8ꢀ,9ꢀ-H), 2.37 (s, 6 H, 8ꢀꢀ-H), 2.17 (s,
12 H, 7ꢀꢀ,9ꢀꢀ-H), 2.09 (s, 12 H, 7ꢀ,10ꢀ-H), 1.85 (s, 12 H, 7ꢀꢀꢀ,9ꢀꢀꢀ-H);
dC (100 MHz, CD2Cl2) 162.7, 160.9, 150.5, 150.2, 150.1, 149.9,
146.4, 145.3, 143.9, 139.8, 139.5, 139.2, 138.9, 138.4, 138.0, 137.9,
136.5, 136.1, 134.9, 134.3, 133.9, 132.3, 131.9, 131.6, 131.3, 130.0,
129.4, 128.6, 128.0, 128.0, 127.5, 127.4, 126.0, 125.2, 122.1, 120.3,
119.9, 119.7, 95.9, 87.9, 21.8, 21.5, 21.2, 21.2, 20.5, 18.7; ESI-MS
m/z (%): 1825.8 (90) [M + H]+, 913.7 (100) [M + 2H]2+; Found:
C, 76.48; H, 5.15; N, 5.84. Calcd for C116H94Br2N8Zn: C, 76.33; H,
5.19; N, 6.14%.
Experimental
Synthesis
Starting materials Phen1 and P1–4 were synthesised according to
known procedures.12,14 Ligands 1,13b 4,13a 13a and 109 were prepared
5
according to previous reports. 1H and 13C NMR were measured on
a Bruker Avance 400. ESI-MS were measured on a ThermoQuest
LCQ Deca instrument. Typically, 25 scans were accumulated for
Using porphyrin P3 (67 mg, 86 lmol), Phen1 (97 mg, 182 lmol),
Pd2(dba)3 (21 mg, 2.2 lmol), AsPh3 (26 mg, 86 lmol). Yield of 3:
130 mg (43%, 37 lmol); dH (400 MHz, CD2Cl2–CD3OD) 8.77 (d,
4 H, J = 4 Hz, 2,8,12,18-Hb), 8.67 (d, 4 H, J = 4 Hz, 3,7,13,17-Hb),
8.65 (s, 2 H, 4-H), 8.36 (d, J = 8 Hz, 2 H, 7-H), 8.13 (d, J = 8 Hz,
one spectrum. All complexes were characterised by 1H NMR, 13
C
NMR, and elemental analysis. Cyclic voltammetry and differential
pulse voltammetry were measured on a Parstat 2273 potentiostat.
ꢀ
4 H, Ar-Hb,Hb ), 7.96 (m, 4 H, 5,6-H), 7.58 (d, J = 8 Hz, 2 H, 8-H),
ꢀꢀꢀ ꢀꢀꢀ
ꢀ
General procedure for synthesis of 1–4. In a three-neck
round-bottomed flask flushed with argon and fitted with a
reflux condenser, zinc porphyrin P1–4 was taken up in dry
benzene–triethylamine (20 mL, 15 : 5). To this solution was
added 3-ethynyl-2-(4-bromo-2,3,5,6-tetramethylphenyl)-9-(2,4,6-
trimethylphenyl)-[1,10]phenanthroline (Phen1). The mixture was
degassed for 30 min under a steady flow of argon. Pd2(dba)3 and
AsPh3 were then added as solids. The reaction was heated at 40 ◦C
for 4 h, after which the reaction mixture was evaporated in vacuo.
The residue obtained was dissolved in dichloromethane, washed
with a solution of 2% KCN and dried over sodium sulfate. The
solid obtained by evaporating the solvents was chromatographed
over silica gel to give the required ligand as a violet solid. The
solid was then dissolved in 1 mL of toluene and loaded over
a size exclusion gel containing BioRad SX-1 Bio-Beads swollen
in toluene, and run under gravity flow. The bright red fractions
collected were identified as the pure product.
7.47 (d, J = 8 Hz, 4 H, Ar-Ha,Ha ), 7.27 (s, 4 H, 3 ,5 -H), 6.96 (s,
4 H, 3ꢀꢀ,5ꢀꢀ-H), 2.60 (s, 6 H, 8ꢀꢀꢀ-H), 2.53 (s, 12 H, 7ꢀꢀꢀ,9ꢀꢀꢀ-H), 2.33 (s,
6 H, 8ꢀꢀ-H), 2.12 (s, 12 H, 7ꢀ,10ꢀ-H), 2.05 (s, 12 H, 7ꢀꢀ,9ꢀꢀ-H), 1.81
(s, 12 H, 8ꢀ,9ꢀ-H); dC (100 MHz, CD2Cl2/CD3OD) 161.1, 150.3,
149.9, 146.2, 145.1, 144.5, 139.8, 139.7, 139.6, 139.1, 138.3, 137.9,
137.8, 136.7, 136.1, 135.0, 134.2, 134.0, 132.1, 130.9, 129.8, 129.4,
128.6, 128.2, 127.9, 127.6, 127.5, 126.1, 125.4, 121.8, 120.6, 120.0,
119.4, 119.3, 105.7, 96.1, 87.7, 21.7, 21.4, 21.1, 21.1, 20.4, 18.6;
ESI-MS m/z (%):1825.8 (75) [M + H]+, 913.9 (100) [M + 2H]2+;
Found: C, 76.25; H, 5.31; N, 5.93. Calcd for C116H94Br2N8Zn: C,
76.33; H, 5.19; N, 6.14%.
Using porphyrin P4 (105 mg, 88 lmol), Phen1 (200 mg,
375 lmol), Pd2(dba)3 (21 mg, 2.2 lmol), AsPh3 (30 mg, 98 lmol).
Yield of 4: 130 mg (51%, 46 lmol); dH (400 MHz, CD2Cl2) 8.93 (s,
8 H, 2,3,7,8,12,13,17,18-Hb), 8.63 (s, 4 H, 4-H), 8.32 (d, J = 8 Hz,
ꢀ
4 H, 7-H), 8.13 (d, J = 8 Hz, 8 H, Ar-Hb,Hb ), 7.89 (br s, 8 H,
5,6-H), 7.58 (d, J = 8 Hz, 4 H, 8-H), 7.53 (d, J = 8 Hz, 8 H,
ꢀꢀꢀ ꢀꢀꢀ
ꢀꢀ ꢀꢀ
ꢀ
Using porphyrin P1 (138 mg, 148 lmol), Phen1 (79 mg,
148 lmol), Pd2(dba)3 (10 mg, 1.5 lmol), AsPh3 (45 mg, 148 lmol).
Yield of 1: 85 mg (43%, 63 lmol); dH (400 MHz, CD2Cl2) 8.84 (d,
J = 4 Hz, 2 H, 2,18-Hb), 8.75 (d, J = 4 Hz, 2 H, 3,17-Hb), 8.70 (s,
4 H, 7,8,12,13-Hb), 8.66 (s, 1 H, 4-H), 8.36 (d, J = 8 Hz, 1 H, 7-H),
Ar-Ha,Ha ), 6.98 (s, 8 H, 3 ,5 -H), 2.55 (s, 24 H, 8 ,9 -H), 2.35
(s, 12 H, 8ꢀꢀꢀ-H), 2.14 (s, 24 H, 7ꢀꢀꢀ,9ꢀꢀꢀ-H), 2.07 (s, 24 H, 7ꢀꢀ,10ꢀꢀ-H).;
dC (100 MHz, CD2Cl2) 162.7, 160.9, 150.3, 146.4, 145.3, 143.7,
139.8, 139.0, 138.4, 137.9, 136.4, 136.1, 134.9, 134.3, 133.9, 132.3,
130.1, 129.3, 129.2, 128.6, 128.5, 128.0, 127.5, 127.4, 126.0, 125.5,
125.2, 122.3, 120.7, 120.2, 95.7, 87.9, 21.2, 21.1, 20.4, 18.6; ESI-
MS m/z (%): 1402.9 (100) [M + 2H]2+, 936.1 (75) [M + 3H]3+,
702.0 (25) [M + 4H]4+; Found: C, 74.25; H, 5.08; N, 5.80. Calcd.
for C176H136Br4N12Zn·2H2O: C, 74.43; H, 4.97; N, 5.92%.
ꢀ
8.16 (d, J = 8 Hz, 2 H, Ar-Hb,Hb ), 7.97 (br s, 2 H, 5,6-H), 7.61
ꢀ
(d, J = 8 Hz, 1 H, 8-H), 7.51 (d, J = 8 Hz, 2 H, Ar-Ha,Ha ), 7.29
(s, 6 H, 3ꢀꢀꢀ,5ꢀꢀꢀ-H), 6.98 (s, 2 H, 3ꢀꢀ,5ꢀꢀ-H), 2.62 (s, 9 H, 8ꢀꢀꢀ,8ꢀꢀꢀꢀ-H),
2.55 (s, 6 H, 8ꢀ,9ꢀ-H), 2.35 (s, 3 H, 8ꢀꢀH), 2.14 (s, 6 H, 7ꢀꢀ,9ꢀꢀ-H), 2.07
(s, 6 H, 7ꢀ,10ꢀ-H), 1.84 (s, 6 H, 7ꢀꢀꢀꢀ,9ꢀꢀꢀꢀ-H), 1.83 (s, 6 H, 7ꢀꢀꢀ,9ꢀꢀꢀ-H);
dC (100 MHz, CDCl3) 163.0, 161.1, 150.5, 150.3, 150.2, 149.7,
146.6, 145.5, 144.9, 142.9, 140.7, 139.7, 138.9, 138.4, 138.0, 137.7,
136.5, 135.1, 134.9, 134.2, 133.8, 132.1, 131.5, 131.1, 130.9, 130.0,
129.7, 129.3, 128.9, 128.8, 128.7, 128.0, 127.6, 127.4, 127.1, 126.1,
125.7, 122.0, 120.7, 119.2, 119.1, 96.3, 88.1, 22.2, 22.1, 21.8, 21.5,
21.4, 20.7, 18.9; ESI-MS m/z (%): 1335.9 (100) [M + H]+; Found:
C, 77.74; H, 5.68; N, 6.28. Calcd for C86H73BrN6Zn: C, 77.32; H,
5.51; N, 6.29%.
Synthesis of ligand 5. 3,8-Dibromophenanthroline (132 mg,
390 lmol) and ferrocenyl acetylene (198 mg, 942 lmol) were placed
in a Schlenk tube flushed with nitrogen. 15 mL of dry benzene
and 15 mL of dry diisopropylamine were added. Subsequently
Pd(PPh3)4 (45 mg, 39 lmol) and copper(I) iodide (7 mg, 39 lmol)
were added under a steady flow of nitrogen. The reaction mixture
was sealed with a Teflon screw cap and stirred for 48 h at 80 ◦C. The
dark brown reaction mixture was evaporated and redissolved in
dichloromethane. The dark solution was then washed with 5%
KCN solution and 10% KOH, and the dichloromethane portion
evaporated to give a dark brown solid. Column chromatography
on silica-gel in dichloromethane–methanol afforded as the third
fraction a dark orange solid, which was found to be the product.
Yield of 5: 98 mg (164 lmol, 42%); dH (400 MHz, CDCl3) 9.21
Using porphyrin P2 (190 mg, 187 lmol), Phen1 (200 mg,
375 lmol), Pd2(dba)3 (18 mg, 1.9 lmol), AsPh3 (57 mg, 187 lmol).
Yield of 2: 157 mg (46%, 86 lmol); dH (400 MHz, CD2Cl2) 8.93 (s,
2 H, 2,3-Hb), 8.88 (d, 2 H, J = 4 Hz, 7,18-Hb), 8.80 (d, J = 4 Hz,
2 H, 8,17-Hb), 8.75 (s, 2 H, 12,13-Hb), 8.68 (s, 2 H, 4-H), 8.33 (d,
ꢀ
J = 8 Hz, 2 H, 7-H), 8.17 (d, J = 8 Hz, 4 H, Ar-Hb,Hb ), 7.92
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(d, J = 2 Hz, 2 H, 2,9-H), 8.28 (d, J = 2 Hz, 2 H, 4,7-H), 7.73 (s, 2
H, 5,6-H), 4.58–4.59 (m, 4 H, 2ꢀ,2ꢀꢀꢀ-H, 5ꢀ,5ꢀꢀꢀ-H), 4.30–4.32 (m, 2 H,
3ꢀ,3ꢀꢀꢀ,4ꢀꢀ,4ꢀꢀꢀ-H), 4.28 (br s, 10 H, 1ꢀꢀ,2ꢀꢀ,3ꢀꢀ,4ꢀꢀ,5ꢀꢀ,1ꢀꢀꢀꢀ,2ꢀꢀꢀꢀ,3ꢀꢀꢀꢀ,4ꢀꢀꢀꢀ,5ꢀꢀꢀꢀ-H);
dC (100 MHz, CDCl3) 152.2, 143.9, 137.4, 127.9, 126.6, 120.3,
93.7, 82.9, 71.6, 70.0, 69.3, 64.1; ESI-MS: C36H25Fe2N2 m/z (100%)
597.4 (100) [M + H]+; Found: C, 68.43; H, 4.54; N, 4.14; Calcd.
4ꢀ,7ꢀ-H), 8.29 (d, J = 8 Hz, 2 H, 5-H ), 8.28 (d, J = 8 Hz, 2 H, 6-H),
ꢀ
8.08 (d, J = 8 Hz, 4 H, Ar-Ha,Ha ), 7.96 (d, J = 8 Hz, 2 H, 8-H),
ꢀ
ꢀ
ꢀ
7.86 (s, 4 H, 5 ,6 -H), 7.48 (d, J = 7.8 Hz, 4 H, Ar-Hb,Hb ), 7.25 (s,
4 H, 3ꢀꢀꢀꢀ,5ꢀꢀꢀꢀ-H), 6.14 (s, 4 H, 3ꢀꢀꢀ,5ꢀꢀꢀ-H), 4.70 (br s, 8 H, 2,5,2ꢀꢀ,5ꢀꢀ-Hcp),
4.43 (br s, 28 H, 3,4,3ꢀꢀ,4ꢀꢀ-1ꢀ,2ꢀ,3ꢀ,4ꢀ,5ꢀ,1ꢀꢀꢀ,2ꢀꢀꢀ,3ꢀꢀꢀ,4ꢀꢀꢀ,5ꢀꢀꢀ-Hcp), 2.59 (s,
6 H, por-mes-Me), 1.92 (s, 12 H, 8ꢀꢀ,9ꢀꢀ-H), 1.90 (s, 12 H, 7ꢀꢀ,10ꢀꢀ-H),
1.77 (s, 12 H, 7ꢀꢀꢀ,9ꢀꢀꢀ-H), 1.75 (s, 12 H, por-mes-Me), 1.62 (s, 6 H, 8ꢀꢀꢀ-
H); dC (100 MHz, CD2Cl2) 161.3, 159.8, 149.9, 144.1, 142.6, 140.7,
139.6, 139.4, 139.0, 138.3, 138.0, 137.9, 137.7, 137.3, 135.1, 134.9,
133.9, 132.7, 132.3, 131.2, 130.2, 130.1, 129.3, 128.8, 128.6, 128.5,
128.2, 128.0, 127.9, 127.7, 127.6, 127.4, 126.6, 123.2, 122.5, 121.2,
116.8, 97.0, 86.2, 81.7, 73.1, 71.8, 30.0, 21.6, 21.5, 20.6, 20.4, 20.3,
18.8; ESI-MS m/z (%): 1572.3 (100) [M2+]; Found: C, 61.04; H,
4.08; N, 4.42; Calcd. for: C188H142Br2Cu2F12Fe4N12P2Zn·4CH2Cl2:
C, 61.09; H, 4.01; N, 4.45%.
1
for C36H24Fe2N2· CH2Cl2: C, 68.36; H, 3.95; N, 4.39%.
2
General procedure for the synthesis of the aggregates 6–
9. To stoichiometric amounts of the porphyrin ligand in
dichloromethane, [Cu(CH3CN)4]PF6 was added. Subsequently,
stoichiometric amounts of 5 was added. The resulting solution
showed an instantaneous change in colour to deep red. The com-
plex was isolated without any further purification and obtained in
quantitative yield.
Triad 6. dH (400 MHz, CD2Cl2) 8.99 (s, 1 H, 4-H), 8.76 (d, J =
Triad 9. dH (400 MHz, CD2Cl2) 8.99 (s, 4 H, 4-H), 8.78 (d, J =
8 Hz, 4 H, 7-H), 8.75 (s, 8 H, Hb), 8.51 (s, 8 H, 2ꢀ,9ꢀ-H), 8.44 (s,
8 H, 4ꢀ,7ꢀ-H), 8.30 (br s, 8 H, 5,6-H), 8.02 (d, J = 8 Hz, 8 H,
8 Hz, 1 H, 7-H), 8.74 (d, J = 4 Hz, 2 H, 2,18-Hb), 8.69 (d, J =
4
4 Hz, 2 H, 3,17-Hb), 8.66 (br s, 4 H, 7,8,12,13-Hb), 8.53 (d, J =
2 Hz, 2 H, 2ꢀ,9ꢀ-H), 8.45 (d, 4J = 2 Hz, 2 H, 4ꢀ,7ꢀ-H), 8.29 (d, J =
9 Hz, 1 H, 5-H ), 8.26 (d, J = 9 Hz, 1 H, 6-H), 8.13 (d, J = 8 Hz,
Ar-Ha,Ha ), 7.98 (d, J = 8.0 Hz, 4 H, 8-H), 7.88 (s, 8 H, 5 ,6 -H),
ꢀ
ꢀ
ꢀ
ꢀꢀꢀ ꢀꢀꢀ
ꢀ
7.46 (d, J = 8 Hz, 8 H, Ar-Hb,Hb ), 6.14 (s, 8 H, 3 ,5 -H), 4.64
ꢀ
ꢀ
2 H, Ar-Ha,Ha ), 7.97 (d, J = 8 Hz, 1 H, 8-H), 7.88 (s, 2 H, 5 ,6 -H),
(s, 16 H, 2,5,2ꢀꢀ,5ꢀꢀ-Hcp), 4.42 (s, 16 H, 3,4,3ꢀꢀ,4ꢀꢀ-Hcp), 4.32 (s, 40 H,
1ꢀ,2ꢀ,3ꢀ,4ꢀ,5ꢀ,1ꢀꢀꢀ,2ꢀꢀꢀ,3ꢀꢀꢀ,4ꢀꢀꢀ,5ꢀꢀꢀ-Hcp), 1.92 (s, 48 H, 7ꢀꢀ,8ꢀꢀ,9ꢀꢀ,10ꢀꢀ-H), 1.76
(s, 24 H, 7ꢀꢀꢀ,9ꢀꢀꢀ-H), 1.63 (s, 12 H, 8ꢀꢀꢀ-H); dC (100 MHz, CD2Cl2)
161.1, 159.7, 150.1, 149.9, 144.1, 142.6, 140.7, 139.8, 139.4, 138.3,
137.9, 137.6, 137.4, 135.1, 134.8, 133.8, 132.7, 132.2, 130.1, 129.2,
128.6, 128.5, 128.1, 128.0, 127.6, 127.4, 126.7, 126.7, 123.1, 122.4,
116.8, 97.5, 96.9, 86.2, 81.8, 72.8, 71.1, 30.0, 20.6, 20.4, 20.3, 18.8;
ESI-MS m/z (%): [M]4+ 1360.5 (100); Found: C, 60.76; H, 4.16; N,
4.47; Calcd. for C320H232Br4Cu4F24Fe8N20P4Zn·4CH2Cl2: C, 61.16;
H, 3.80; N, 4.40%.
ꢀ
ꢀꢀꢀꢀ ꢀꢀꢀꢀ
ꢀ
7.48 (d, J = 8 Hz, 2 H, Ar-Hb,Hb ), 7.23 (s, 6 H, 3 ,5 -H), 6.16 (s,
2 H, 3ꢀꢀꢀ,5ꢀꢀꢀ-H), 4.57 (d, J = 5 Hz, 4 H, 2,5,2ꢀꢀ,5ꢀꢀ-Hcp), 4.35 (d, J =
3 Hz, 4 H, 3,4,3ꢀꢀ,4ꢀꢀ-Hcp), 4.26 (s, 10 H, 1ꢀ,2ꢀ,3ꢀ,4ꢀ,5ꢀ,1ꢀꢀꢀ,2ꢀꢀꢀ,3ꢀꢀꢀ,4ꢀꢀꢀ,5ꢀꢀꢀ-
Hcp) 2.58 (s, 6 H, por-mes-Me ), 2.56 (s, 3H, por-mes-Me), 1.95
(s, 6 H, 8ꢀꢀ,9ꢀꢀ-H), 1.93 (s, 6 H, 7ꢀꢀ,10ꢀꢀ), 1.79 (s, 12 H, por-mes-Me),
1.77 (s, 6 H, 7ꢀꢀꢀ,9ꢀꢀꢀ-H), 1.76 (s, 6 H, por-mes-Me),1.64 (s, 3 H,
8ꢀꢀꢀ-H); dC (100 MHz, CD2Cl2) 161.3, 159.9, 150.3, 150.1, 149.9,
149.8, 144.1, 142.6, 140.8, 139.7, 139.6, 139.5, 139.4, 138.3, 138.0,
137.8, 137.7, 137.3, 135.2, 135.0, 133.9, 132.8, 131.8, 131.4, 131.3,
130.9, 130.0, 129.3, 128.6, 128.5, 128.2, 128.1, 127.9, 127.6 127.4,
127.3, 126.7, 123.3, 122.5, 120.9, 119.0, 118.7, 116.9, 98.0, 96.9,
86.1, 81.8, 72.3, 70.5, 70.3, 21.8, 21.5, 20.6, 20.4, 20.3, 18.8; ESI-
MS m/z (%): 1995.7(100) [M]+. Found: C, 65.88; H, 4.36; N, 5.65.
Calcd for C122H97BrCuF6Fe2N8PZn·CH2Cl2: C, 66.38; H, 4.48; N,
5.03%.
General procedure for the synthesis of the aggregates 11–14.
To stoichiometric amounts of the porphyrin–Cu(phen)2–ferrocene
aggregates in dichloromethane, a solution of the fullerene 10 in
CS2 was added. The resulting solution showed an instantaneous
change in colour to greenish-brown. The complex was isolated
without any further purification.
Triad 7. dH (400 MHz, CD2Cl2) 9.00 (s, 2 H, 4-H), 8.77 (d, J =
8 Hz, 2 H, 7-H), 8.76 (s, 2 H, 2,3-Hb), 8.73 (d, J = 4 Hz, 2 H,
7,18-Hb), 8.69 (d, J = 4 Hz, 2 H, 8,17-Hb), 8.68 (s, 2 H, 12,13-Hb),
8.53 (d, J = 2 Hz, 4 H, 2ꢀ,9ꢀ-H), 8.46 (s, 4 H, 4ꢀ,7ꢀ-H), 8.31 (d, J =
8 Hz, 2 H, 5-H), 8.28 (d, J = 8 Hz, 2 H, 6-H), 8.06 (d, J = 8 Hz,
Tetrad 11. dH (400 MHz, CD2Cl2–CS2) 8.97 (s, 1 H, 4-H), 8.81
(d, J = 8 Hz, 1 H, 7-H), 8.63 (d, J = 4 Hz, 2 H, 2,18-Hb), 8.57
(d, J = 4 Hz, 2 H, 3,17-Hb), 8.55 (br s, 4 H, 7,8,12,13-Hb), 8.54
4
4
(d, J = 2 Hz, 2 H, 2ꢀ,9ꢀ-H), 8.44 (d, J = 2 Hz, 2 H, 4ꢀ,7ꢀ-H),
ꢀ
ꢀ
ꢀ
4 H, Ar-Ha,Ha ), 7.97 (d, J = 8 Hz, 2 H, 8-H), 7.89 (s, 4 H, 5 ,6 -
8.35 (d, J = 9 Hz, 1 H, 5-H ), 8.30 (d, J = 9 Hz, 1 H, 6-H), 8.04
ꢀꢀꢀꢀ ꢀꢀꢀꢀ
ꢀ
ꢀ
H), 7.48 (d, J = 8 Hz, 4 H, Ar-Hb,Hb ), 7.26 (s, 4 H, 3 ,5 -H),
(d, J = 8 Hz, 2 H, Ar-Ha,Ha ), 7.96 (d, J = 8 Hz, 1 H, 8-H),
6.16 (s, 4 H, 3ꢀꢀꢀ,5ꢀꢀꢀ-H), 4.60 (s, 8 H, 2,5,2ꢀꢀ,5ꢀꢀ-Hcp), 4.38 (s, 8 H,
3,4,3ꢀꢀ,4ꢀꢀ-Hcp), 4.29 (s, 20 H, 1ꢀ,2ꢀ,3ꢀ,4ꢀ,5ꢀ,1ꢀꢀꢀ,2ꢀꢀꢀ,3ꢀꢀꢀ,4ꢀꢀꢀ,5ꢀꢀꢀ-Hcp), 2.58
(s, 6 H, por-mes-Me), 1.94 (s, 12 H, 8ꢀꢀ,9ꢀꢀ-H), 1.93 (s, 12 H, 7ꢀꢀ,9ꢀꢀ-
H), 1.79 (s, 12 H, 7ꢀꢀꢀ,9ꢀꢀꢀ-H ), 1.77 (s, 12 H, por-mes-Me), 1.64 (s,
6 H, 8ꢀꢀꢀ-H); dC (100 MHz, CD2Cl2), 161.2, 159.8, 150.6, 150.2,
149.9, 149.7, 144.5, 144.1, 142.6, 140.8, 139.7, 139.4, 139.0, 138.3,
138.1, 137.9, 137.7, 137.3, 135.2, 134.9, 133.9, 132.8, 131.7, 131.3,
130.1, 129.3, 128.7, 128.6, 128.5, 128.2, 128.0, 127.9, 127.6, 127.4,
127.3, 126.7, 123.2, 122.5, 121.2, 119.9, 119.5, 116.9, 97.8, 96.9,
86.2, 81.8, 77.9, 72.3, 70.6, 70.4, 63.4, 21.7, 21.5, 20.6, 20.4, 20.3,
18.8; ESI-MS m/z (%): 1572.3 (100) [M]2+ Found: C, 60.68; H,
3.93; N, 4.54 Calcd. for C188H142Br2Cu2F12Fe4N12P2Zn·4CH2Cl2:
C, 61.09; H, 4.01; N, 4.45%.
7.89 (s, 2 H, 5 ,6 -H), 7.41 (d, J = 8 Hz, 2 H, Ar-Hb,Hb ), 7.20
(s, 6 H, 3ꢀꢀꢀꢀ,5ꢀꢀꢀꢀ-H), 6.45 (br s, 2 H, 3,5-Hpy), 6.20 (s, 2 H, 3ꢀꢀꢀ,5ꢀꢀꢀ-
H), 4.66 (d, J = 9 Hz, 1 H, pyr-H5a), 4.58 (s, 4 H, 2,5,2ꢀꢀ,5ꢀꢀ-Hcp),
4.56 (s, 2 H, pyr-H2), 4.36 (s, 4 H, 3,4,3ꢀꢀ,4ꢀꢀ-Hcp), 4.27 (s, 10 H,
1ꢀ,2ꢀ,3ꢀ,4ꢀ,5ꢀ,1ꢀꢀꢀ,2ꢀꢀꢀ,3ꢀꢀꢀ,4ꢀꢀꢀ,5ꢀꢀꢀ-Hcp), 3.92 (d, J = 9 Hz, 1 H, pyr-H5b),
2.59 (s, 9 H, por-mes-Me), 1.97 (s, 6 H, 8ꢀꢀ,9ꢀꢀ-H), 1.93 (s, 6 H,
7ꢀꢀ,10ꢀꢀ-H),1.82 (s, 6 H, 7ꢀꢀꢀ,9ꢀꢀꢀ-H), 1.73 (s, 18 H, por-mes-Me), 1.71
(s, 3 H, 8ꢀꢀꢀ-H), 1.27 (s, 3 H, N–CH3–C60); dC (100 MHz, CD2Cl2)
206.1, 192.8, 161.0, 159.6, 155.8, 153.5, 151.8, 151.2, 149.9, 149.8,
149.6, 149.3, 147.4, 146.3 (2), 146.2, 146.0, 145.7, 145.5(2), 145.4,
145.3, 145.2, 145.1, 144.7, 144.5, 144.4, 144.3, 144.0, 143.1, 143.0,
142.7, 142.6, 142.5, 142.2 (2), 142.1, 142.0, 141.9, 141.8, 141.7,
141.6, 141.5, 140.6, 140.2, 139.7(2), 139.6, 139.4, 139.2, 138.1,
137.8, 137.6, 137.3, 137.2, 136.7, 136.1, 135.9, 135.5, 135.0, 133.9,
132.7, 131.6, 131.2, 131.0, 130.6, 129.8, 129.2, 128.5, 128.4, 128.0,
127.9, 127.8, 127.5, 127.4, 127.3, 127.2, 126.6, 123.1, 122.4, 120.5,
ꢀ
ꢀ
ꢀ
Triad 8. dH (400 MHz, CD2Cl2) 8.98 (s, 2 H, 4-H), 8.77 (d, J =
8 Hz, 2 H, 7-H), 8.75 (d, J = 4 Hz, 4 H, 2,8,12,18-Hb), 8.69 (d,
J = 4 Hz, 4 H, 3,7,13,17-Hb), 8.49 (s, 4 H, 2ꢀ,9ꢀ-H), 8.41 (s, 4 H,
84 | Org. Biomol. Chem., 2007, 5, 78–86
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118.7, 118.6, 118.3, 97.9, 96.7, 81.8, 80.9, 72.3, 70.5, 70.3, 54.3,
39.1, 30.8, 21.9, 21.8, 21.4, 20.3, 20.2, 18.7. Found: C, 73.85; H,
Hcp), 4.30 (s, 40 H, 1ꢀ,2ꢀ,3ꢀ,4ꢀ,5ꢀ,1ꢀꢀꢀ,2ꢀꢀꢀ,3ꢀꢀꢀ,4ꢀꢀꢀ,5ꢀꢀꢀ-Hcp), 3.95 (d, J =
9 Hz, 1 H, pyr-H5b),1.94 (s, 24 H, 7ꢀꢀ,8ꢀꢀ-H) 1.90 (s, 24 H, 9ꢀꢀ,10ꢀꢀ-H),
1.78 (s, 24 H, 7ꢀꢀꢀ,9ꢀꢀꢀ-H), 1.68 (s, 12 H, 8ꢀꢀꢀ-H), 1.28 (s, 3H, N-CH3);
dC (100 MHz, C2D4Cl2) 206.0, 192.8, 149.9, 147.4, 146.2, 146.1,
145.9, 145.5, 145.3, 144.3, 142.5, 141.9, 140.6, 140.1, 139.8, 139.5,
138.1, 137.6, 137.2, 136.4, 135.9, 135.0, 134.9, 134.9, 134.1, 133.8,
132.8, 131.8, 129.8, 128.6, 128.4, 128.0, 127.9, 127.5, 127.3, 127.2,
122.4, 120.8, 96.7, 86.2, 81.8, 72.3, 70.5, 70.4, 70.3, 63.3, 54.3, 39.1,
30.8, 21.1, 20.4, 20.3, 20.2, 18.7; Found: C, 61.89; H, 3.59; N, 3.91
Calcd. for C388H242Br4Cu4F24Fe8N22P4Zn·10CH2Cl2 : C, C, 61.86;
H, 3.42; N, 3.99%.
3.75; N, 4.41. Calcd. for C190H107BrCuF6Fe2N10PZn·11 CH2Cl2: C,
2
73.65; H, 3.55; N, 4.49%.
Tetrad 12. dH (400 MHz, C2D4Cl2) 8.98 (s, 2 H, 4-H), 8.75 (d,
J = 8 Hz, 2 H, 7-H), 8.62 (s, 2 H, 2,3-Hb), 8.59 (d, J = 4 Hz, 2 H,
7,18-Hb), 8.54 (d, J = 4 Hz, 2 H, 8,17-Hb), 8.51 (s, 2 H, 12,13-Hb),
8.47 (d, J = 2 Hz, 4 H, 2ꢀ,9ꢀ-H), 8.44 (d, J = 2 Hz, 4 H, 4ꢀ,7ꢀ-H),
8.29 (d, J = 8 Hz, 2 H, 5-H), 8.28 (d, J = 8 Hz, 2 H, 6-H), 7.97 (d,
ꢀ
J = 8 Hz, 4 H, Ar-Ha,-Ha ), 7.95 (d, J = 8 Hz, 2 H, 8-H), 7.85 (s, 4
ꢀ
ꢀ
ꢀꢀꢀꢀ ꢀꢀꢀꢀ
ꢀ
H, 5 ,6 -H), 7.42 (d, J = 8 Hz, 4 H, Ar-Hb,Hb ), 7.16 (s, 4 H, 3 ,5 -
H), 6.26 (br s, 2 H, 3,5-Hpy), 6.07 (s, 4 H, 3ꢀꢀꢀ,5ꢀꢀꢀ-H), 4.57 (s, 8 H,
2,5,2ꢀꢀ,5ꢀꢀ-Hcp), 4.36 (s, 1 H, pyr-H2), 4.33 (s, 8 H, 3,4,3ꢀꢀ,4ꢀꢀ-Hcp), 4.24
(s, 20 H, 1ꢀ,2ꢀ,3ꢀ,4ꢀ,5ꢀ,1ꢀꢀꢀ,2ꢀꢀꢀ,3ꢀꢀꢀ,4ꢀꢀꢀ,5ꢀꢀꢀ-Hcp), 4.22 (d, J = 9 Hz, 1 H,
pyr-H5b), 2.52 (s, 6 H, por-mes-Me), 1.91 (s, 12 H, 8ꢀꢀ,9ꢀꢀ-H), 1.87
(s, 12 H, 7ꢀꢀ,10ꢀꢀ-H), 1.72 (s, 12 H, 7ꢀꢀꢀ,9ꢀꢀꢀ-H), 1.64 (s, 12 H, por-mes-
Me), 1.56 (s, 6 H, 8ꢀꢀꢀ-H), 1.23 (s, 3 H, N–CH3–C60). dC (100 MHz,
C2D4Cl2) 206.0, 192.7, 160.9, 159.5, 155.7, 153.4, 151.7, 151.2,
150.1, 149.9, 149.7, 149.6, 149.3, 146.2, 146.0, 145.4(2), 145.3(2),
145.2, 145.1, 145.0, 144.9, 144.6, 144.0, 142.8, 142.6, 142.5, 142.4,
142.0, 141.9, 141.8, 141.7, 141.5, 140.6, 140.1, 139.7, 139.4, 139.2,
138.1, 137.8, 137.6, 137.5, 137.2, 135.0, 133.8, 132.9, 131.8, 131.3,
130.9, 129.8, 129.1, 128.5, 128.4, 128.0, 127.9, 127.8, 127.5, 127.3,
126.6, 123.0, 122.4, 120.6, 119.3, 118.9, 97.7, 96.7, 86.2, 81.8, 72.3,
70.6, 70.3, 63.4, 54.3, 39.1, 30.8, 21.9, 21.4, 20.4, 20.3, 20.2, 18.7
ESI-MS m/z (%): [M]2+ 1999.0 (20); Found: C, 65.61; H, 3.53; N,
3.97; Calcd. for C256H152Br2Cu2F12Fe4N14P2Zn·6CH2Cl2: C, 65.57;
H, 3.44; N, 4.09%.
Acknowledgements
This publication is dedicated to Professor Dr Manfred Christl
(Universita¨t Wu¨rzburg) on the occasion of his 65th birthday.
We are grateful to the Deutsche Forschungsgemeinschaft and the
Fonds der Chemischen Industrie for continued financial support.
References
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ꢀ
H, 6-H), 7.98 (d, J = 8 Hz, 4 H, Ar-Ha,Ha ), 7.97 (d, J = 8 Hz,
2 H, 8-H), 7.87 (s, 4 H, 5ꢀ,6ꢀ-H), 7.44 (d, J = 7.8 Hz, 4 H, Ar-
ꢀꢀꢀꢀ ꢀꢀꢀꢀ
ꢀ
Hb,Hb ), 7.19 (s, 6 H, 3 ,5 -H), 6.22 (br s, 2 H, 3,5-Hpy), 6.08
(s, 4 H, 3ꢀꢀꢀ,5ꢀꢀꢀ-H), 4.63 (s, 8 H, 2,5,2ꢀꢀ,5ꢀꢀ-Hcp), 4.57 (d, J = 9 Hz,
1 H, pyr-H5a), 4.45 (s, 1 H, pyr-H2), 4.38 (s, 8 H, 3,4,3ꢀꢀ,4ꢀꢀ-Hcp),
4.29 (s, 20 H, 1ꢀ,2ꢀ,3ꢀ,4ꢀ,5ꢀ,1ꢀꢀꢀ,2ꢀꢀꢀ,3ꢀꢀꢀ,4ꢀꢀꢀ,5ꢀꢀꢀ-Hcp), 3.83 (d, J = 9 Hz,
1 H, pyr-H5b), 2.54 (s, 6 H, por-mes-Me), 1.94 (s, 12 H, 8ꢀꢀ,9ꢀꢀ-H),
1.89 (s, 12 H, 7ꢀꢀ,10ꢀꢀ-H), 1.75 (s, 12 H, 7ꢀꢀꢀ,9ꢀꢀꢀ-H), 1.67 (s, 12 H,
por-mes-Me), 1.57 (s, 6 H, 8ꢀꢀꢀ-H), 1.25 (s, 3 H, N–CH3–C60);
dC (100 MHz, C2D4Cl2) 206.1, 192.8, 160.9, 159.6, 155.8, 153.5,
149.9, 146.3, 146.2, 146.0, 145.5(2), 145.4, 145.2, 144.8, 144.5,
144.4, 144.3, 144.0, 142.8, 142.7, 142.6, 142.5, 142.2(2), 142.1,
141.8, 141.5, 140.6, 140.2, 139.7, 139.4, 139.3, 139.2, 138.1, 137.8,
137.6, 137.5, 137.2, 136.2, 135.9, 135.5, 135.0, 133.9, 132.8, 132.0,
130.8, 129.9, 129.2, 128.5, 128.4, 128.0, 127.9, 127.8, 127.5, 127.3,
127.2, 126.5, 123.0, 122.4, 120.6, 97.8, 96.7, 96.2, 81.8, 72.5, 70.8,
70.6, 54.3, 39.1, 30.8, 21.8, 21.4, 20.3, 20.2, 18.7. ESI-MS m/z
(%): [M]2+ 1999.5 (60); Found: C, 67.49; H, 3.65; N, 4.15. Calcd.
for C256H152Br2Cu2F12Fe4N14P2Zn)·4CH2Cl2: C, 67.46; H, 3.48; N,
4.24%.
Tetrad 14. dH (400 MHz, CD2Cl2–CS2): 8.99 (s, 4 H, 4-H), 8.78
(d, J = 8 Hz, 4 H, 7-H), 8.67 (s, 8 H, Hb), 8.51 (s, 8 H, 2ꢀ,9ꢀ-H),
8.44 (s, 8 H, 4ꢀ,7ꢀ-H), 8.32 (s, 8 H, 5,6-H), 7.96 (d, J = 8 Hz, 8 H,
ꢀ
ꢀ
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Ar-Ha,Ha ), 7.94 (d, J = 8.0 Hz, 4 H, 8-H), 7.89 (s, 8 H, 5 ,6 -H),
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7.40 (d, J = 8 Hz, 8 H, Ar-Hb,Hb ), 6.23 (br s, 2 H, 3,5-Hpy), 6.18
(s, 8 H, 3ꢀꢀꢀ-H, 5ꢀꢀꢀ-H), 4.77 (d, J = 9 Hz, 1 H, pyr-H5a), 4.62 (s,
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