Construction of hexanuclear macrocycles by a coupling strategy from polyfunctionalized bis(terpyridines)

Article abstract of DOI:10.1039/b811607e

The construction of a heteronuclear (Ru₄Fe₂) hexameric metallomacrocycle with methyl- and carbonyl-functionalized bis(terpyridyl) moieties was achieved by a self-assembly of a dinuclear trimer, which was prepared in high yield via Pd

Full text of DOI:10.1039/b811607e

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PAPER
www.rsc.org/njc | New Journal of Chemistry
Construction of hexanuclear macrocycles by a coupling strategy
from polyfunctionalized bis(terpyridines)wz
Ibrahim Eryazicia and George R. Newkome*ab
Received (in Montpellier, France) 9th July 2008, Accepted 26th September 2008
First published as an Advance Article on the web 5th December 2008
DOI: 10.1039/b811607e
The construction of a heteronuclear (Ru4Fe2) hexameric metallomacrocycle with methyl- and
carbonyl-functionalized bis(terpyridyl) moieties was achieved by a self-assembly of a dinuclear
trimer, which was prepared in high yield via Pd(0) coupling of a bis-iodo functionalized dinuclear
complex with a terpyridine possessing an acetylene group.
In this work, the synthesis and characterization of func-
Introduction
tionalized mononuclear Fe(II) and Ru(II) complexes (25–28 and
33–39, respectively), as well as the preparation of tetra(ethoxy-
carbonyl)-bis(terpyridine) 15 and tetramethyl-bis(terpyridine) 8
There has been considerable research conducted on octahedral
terpyridine transition metal complexes, especially regarding the
fine-tuning of their electrochemical, photophysical and optical
properties, as well as precursors to build supramolecular archi-
tectures.1 However, functionalized terpyridine complexes have
been, by and large, underutilized relative to their unsubstituted
counterparts due to their limited accessibility and the generally
poor yields of metal complexation, even though they have been
shown to possess interesting luminescent properties.2–6 They
have also been utilized as chemosensors,7,8 fluorescent immuno-
assay agents,9–12 as well as catalysts13–16 and dye-synthesized
solar cells.17–22
and 9 via Pd[0]-coupling and Krohnke34 method, respectively, are
¨
discussed. The facile and high yield complexation procedures of
dimethylterpyridines with di(ethoxycarbonyl)terpyridine 32 were
used as a basic strategy to prepare dinuclear complexes 40 and 44,
which are the precursors for the dinuclear trimer 46. An alter-
native coupling route to construct the functionalized dinuclear
complex 44, which was used as a precursor to assemble a hexa-
nuclear metallomacrocycle 47 containing mixed metals (Ru4Fe2)
and three different terpyridinyl moieties with eight methyl and
eight ethoxycarbonyl groups, will be presented. The single-crystal
X-ray structures of bis(terpyridine) 9 and homoleptic complex 38
are also presented.
Carboxylic acids or carboxylates have been the favored
terpyridine functional groups, since they play a crucial role for
surface anchoring as well as act as potential internal counter-
ions. For example, a black dye containing a terpyridine with
three carboxylates was attached to nanocrystalline TiO2 surface
for use as a solar cell that demonstrated an overall conversion
efficiency of 10.4% (Fig. 1).18 Carboxylate groups have also
been introduced at the 4-position of terpyridine Ru(II) com-
plex ([Ru(40-phenyl-4-carboxylate-2,20:60,200-terpyridine)2]0) in
order to promote a photoinduced electron transfer via ionic
interactions with methyl viologen.23
Results and discussion
Synthesis of tetramethyl substituted bis(terpyridines) 8 and 9
was achieved via a two-step Krohnke34 procedure (Scheme 2).
¨
Treatment of dialdehydes 2 and 5 with four equivalents of
2-acetyl-4-methylpyridine gave bis(diketone) intermediates 6
and 7, respectively, then the ring-closure of these intermediates
in the presence of NH4OAc and AcOH afforded the desired
bis(terpyridines) 8 and 9 in albeit poor yields (6–13%). Proton
resonances (1H NMR) for the terpyridinyl moieties of ligands
8 and 9 showed upfield shifts for 5,500-, 6,600- and 3,300-tpyHs
(Dd = 0.16–0.23) compared to 1,3-bis(2,20:60,200-terpyridin-40-yl)-
5-R-benzene25 (R = Br, Me) due to shielding effect of
four electron-donating methyl moieties. The HRMS spectra
of 8 further confirmed its structure by a single peak at
m/z = 675.1850 [M + H]+.
The construction of ‘‘benzenoid-based’’ metallomacrocycles
was achieved via either a one-pot self-assembly or step-wise
sequence from 1201 juxtaposed bis(terpyridine) ligands and
various transition metals [Fe(II), Ru(II), Zn(II); Scheme 1].24–31
These supramolecular architectures displayed luminescence
properties when constructed with Zn(II),29,30 electrostatically
attached to multi-wall carbon nanotubes,31,32 and utilized as a
molecular nanotemplate.33
a Department of Polymer Science, The University of Akron, Akron,
OH 44325-4717, USA
b Department of Chemistry, The University of Akron, Akron, OH
44325-4717, USA. E-mail: newkome@uakron.edu;
Fax: +1 330 972 2413; Tel: +1 330 972 6458;
Web: www.dendrimers.com
w Dedicated to Professor Jean-Pierre Sauvage on the occasion of his
65th birthday.
Fig. 1 Structures of carboxylate functionalized Ru(II)-terpyridine
complexes.18,23
z CCDC reference numbers 692580 and 692581. For crystallographic
data in CIF or other electronic format see DOI: 10.1039/b811607e
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Scheme 1 The construction of hexanuclear metallomacrocycles via either self-assembly or a step-wise manner.24–31
Scheme 2 Synthesis of bis(terpyridines) 8 and 9 via the Krohnke34 method. Reagents and conditions: (i) BH3ꢁTHF, THF, 25 1C, 10 h; (ii) PCC,
¨
DCM, 25 1C, 2 h; (iii) HTMA, CHCl3, 70 1C, 1 h, N2; (iv) AcOH/H2O (1 : 9), 98 1C, 1 h, N2; (v) NaOH (4 M), MeOH, 25 1C, 9 h; (vi) AcOH,
NH4OAc, 110 1C, 11 h.
The single-crystal X-ray structure of ligand 9 confirmed the
proposed structure (Fig. 2). The three pyridine rings showed a
transoid arrangement about the interannular C–C bonds,
which was in agreement with the literature.35–38 This con-
figuration minimizes electrostatic interactions between the
nitrogen lone pairs and van der Waals interactions between
the meta protons.35 The interannular C–C bond lengths of
bis(terpyridine) 9 [1.487(8)–1.496(4) A] are comparable with
terpyridines [1.480(1)–1.498(3) A] found in the literature.35–37
The three pyridine rings are not exactly coplanar and the
torsion angles of two terminal rings with the central pyridine
ring are 13.08, 19.72 and 8.34, 12.081 for each terpyridine
moiety of 9, which are higher than 40-(4-bromophenyl)-
4,400-dimethylterpyridine39 (9.48 and 1.061). The central
Fig. 2 ORTEP drawing of bis(terpyridine) 9 with atoms shown at
benzene ring connected to the terpyridines is also distorted
50% probability.
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with torsion angles of 57.53 and 36.611, which are comparable
to that of 40-(4-bromophenyl)-4,400-dimethylterpyridine39 (391)
and 40-(2,5-dimethoxyphenyl)terpyridine40 (50.41).
Preparation of the bis(terpyridines) 14 and 15 was achieved
via Pd[0]-mediated cross-coupling41 of terpyridines 12 and 13
with 1,3-diethynyltoluene42 (10, Scheme 3). Proton resonances
(1H NMR) for the terpyridinyl moiety of the ligand 15 showed
downfield shifts for the 5,500-tpyH (d = 7.94, Dd = 0.58) and
3,300-tpyH (d = 9.22, Dd = 0.52) compared to bis(terpyridine)
14 due to deshielding effect of four electron-withdrawing
ethoxycarbonyl moieties. The HRMS spectra of 14 and
15 further confirm their structures by single peaks at m/z =
755.2910 and 1043.3726 [M + H]+, respectively. Terpyridines
17 and 20 containing free acetylene functionality were pre-
pared by fluoride-based removal of the deprotected trimethyl-
silyl groups on terpyridines 19 and 16, which were each
synthesized via Pd[0]-mediated coupling of the aryl iodide 13
with 11 and 18 with Me3Si–CRCH, respectively. Structures
of terpyridines 16–20 were confirmed by 1H, 13C, COSY NMR
and HRMS spectroscopy (experimental section).
Scheme
4
Synthesis of mononuclear Fe(II)-complexes 25–28.
Reagents and conditions: (i) FeCl2ꢁ4H2O, MeOH, 60 1C, 8–20 h, then
NH4PF6.
not superimposable on their mirror images; however, attempts
to separate the structural isomers were unsuccessful. The
structures of 25–28 were established via HRMS and ESI-MS
by the unique signals at m/z = 444.0342, 430.0191, 441.0 and
473.0 corresponding to [M ꢂ 2Cl]2+, respectively, as well as
1
their H NMR spectra.
Treatment of functionalized terpyridines 21–24 with
0.5 equivalence of FeCl2ꢁ4H2O in MeOH gave a purple
solution that was concentrated in vacuo and dried to afford
The UV-Vis spectra of these complexes revealed a charac-
teristic MLCT band at 570–577 nm in MeOH at 25 1C (Fig. 3).
This absorption lies in the visible region and is responsible for
the intense purple color of the complexes. Complexes 27
and 28 containing electron-withdrawing cyano and methoxy-
carbonyl groups displayed a slightly blue shifted MLCT
(7 nm) when compared to complexes 25 and 26 with
electron-donating methyl groups.
1
complexes 25–28 (Scheme 4) in 490% yield. The H NMR
spectra of these complexes displayed a characteristic upfield
shift of 6,600-tpyH (Dd = 1.25–1.59) compared to the ligands
because the 6,600-protons are located above-the-plane of the
aromatic ring of the adjacent ligand. The complexes 26–28
containing unsymmetrical ligands showed unique proton
resonances for each pyridine ring as a result of diminished
symmetry. The disubstituted complexes 26–28 are believed to
be structurally chiral because these octahedral complexes are
Homoleptic Ru(II)-terpyridine complexes 33 and 34 were
obtained by refluxing the dimethylterpyridine 21 and di(methoxy-
carbonyl)terpyridine 30 with 0.5 equivalents of RuCl3ꢁ3H2O
in MeOH under reducing conditions (N-ethylmorpholine) for
Scheme 3 Synthesis of bis(terpyridines) 14 and 15 and terpyridines 16, 17, 19 and 20 via coupling strategy. Reagents and conditions: (i) n-BuLi,
Me3SiCl, THF, ꢂ78 1C, 6 h, N2; (ii) 12 or 13, Pd(PPh3)4, CuI, THF/NEt3, 80 1C, 11 h, (iii) KF, THF/EtOH, 25 1C, 10 h; (iv) Me3SiCRCH,
Pd(PPh3)4, CuI, THF/NEt3, 80 1C, 11 h, argon; (v) (n-Bu)4NFꢁ3H2O, THF, 25 1C, 6 h.
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of terpyridine peaks. Mass spectral data (HRMS) of 33–39 were
also in accord with the assigned structures and isotope patterns of
the peaks perfectly matched the theoretical values.
The methoxy- and ethoxycarbonyl groups in 34, 36 and 38
were hydrolyzed with aqueous NaOH (1 M, excess) in DMF at
60 1C for 12 hours affording the corresponding sodium
carboxylate salts, which were protonated (TFA) to give the
desired carboxylic acid terpyridine complexes 35, 37 and 39,
1
respectively, in 490% yields. The H NMR spectra of these
acids were identical to their starting ester complexes except
they did not contain methoxy- or ethoxycarbonyl peaks.
Single crystals of homoleptic complex 38[(PF6)2] were
grown in MeCN and the X-ray analysis (100 K) confirmed
the proposed pseudo-octahedral structure (Fig. 4A). The
crystal is orthorhombic with space group P212121 and each
complex has two PF6ꢂ ions and one MeCN in the lattice. The
angle of N(1)–Ru(1)–N(2) is 1781 and the mean angle between
the two terpyridines is 92.81; thus, the two terpyridines are
tilted 2–2.81 away from perfect orthogonality. The torsion
angles of two terminal pyridine rings with central pyridine ring
are between 1.14–3.601, which are almost perfectly coplanar.
The edge-to-edge distances of the complex 38 are 20 and 22 A
(Fig. 4B). The shortest distance between Ru(II) metals is 10.1 A
in the lattice and Ru(II) metal centers are 4.88 and 7.18 A away
from MeCN and PF6ꢂ, respectively.
Fig. 3 UV-Vis spectra of Fe(II)-terpyridine complexes 25–28 in
MeOH at 25 1C.
10 and 20 h, respectively (Scheme 5). The lower reaction yield of
34 (40%) compared to 33 (98%) was rationalized by the insolu-
bility of the ligand 30. Although terpyridines possessing electron-
withdrawing groups should lead to weaker complexes, to address
the solubility issue, the di(methoxycarbonyl) groups were con-
verted to di(ethoxycarbonyl) analogs, as in 29 and 13. The
metalated adducts 31 and 32 were prepared by treating these
terpyridines with RuCl3ꢁ3H2O (41 eq.) in 480% yields. The
adduct 32 was treated with one equivalent of ligand 13 under
reducing conditions (N-ethylmorpholine) to give homoleptic com-
plex 38 in 55% yield. The yield was finally optimized when the
adduct 31 was treated with dimethyl ligand 21 affording the
heteroleptic complex 36 in nearly quantitative yield. The com-
plexes 33, 34, 36 and 38 exhibited a characteristic upfield shift
(1H NMR) for the 6,600-tpyH (Dd = 1.22–1.30) compared to the
free ligands; moreover, heteroleptic 36 displayed two different sets
The molecular packing of crystals of 38 did not show any
p–p interactions between aromatic rings (Fig. 4C); however, it
revealed short distances between Iꢁ ꢁ ꢁOQC (3.15–3.2 A) when
visualized along b axis (Fig. 5). These short iodo-carbonyl
interactions dominated the lattice and played a crucial role in
the crystallization process, while MeCN molecules did not
show any bonding.
Scheme 5 Synthesis of mononuclear Ru(II)-complexes 35–41. Reagents and conditions: (i) 29 or 13, RuCl3ꢁ3H2O (41 eq.), EtOH/THF, 70 1C,
15 h; (ii) 13, or 21, N-ethylmorpholine, EtOH, 70 1C, 10–24 h, then NH4PF6; (iii) 21 or 30, RuCl3ꢁ3H2O (0.5 eq.), N-ethylmorpholine, MeOH,
70 1C, 10–20 h; (iv) NaOH (1 M), DMF, 60 1C, 12 h, TFA.
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the visible region and are responsible for the intense red color
of the complexes. The hypsochromic shift (10 nm) of MLCT
of complex 33 compared to 35–39 is due to its electron-
donating four methyl moieties. Further, MLCT band (503 nm)
of complexes 36 and 37 showed a shoulder at ca. 490 nm because
of the two methyl moieties.
The construction of dinuclear Ru(II)-complexes 40 and 44
containing di-iodo functionality was achieved by treating
bis(terpyridines) 14 and 8 with two equivalents of the
metalated adduct 32, respectively, under reducing conditions
(N-ethylmorpholine, Scheme 6 and Scheme 7). The reaction
mixture of 14 and 32 was chromatographed (SiO2) eluting with
MeCN–sat. KNO3 (aq)–H2O (20 : 1 : 1) then the counterion
was exchanged by treating with an excess NH4PF6 (1 M) to
afford the desired dinuclear 40[(PF6)2] in 57% yield. On the
other hand, dimetallic 44[(Cl)2] was obtained in quantitative
yield by just in vacuo removing the solvent and drying the
residue. The 1H NMR spectra of 40[(PF6)2] in CD3CN and
44[(Cl)2] in CD3OD displayed two set of proton peaks for each
terpyridine moiety with 1 : 1 proton integration ratio suppor-
ting the dinuclear structures and they also showed the
characteristic upfield and downfield shifts for 6,600-tpyH
(Dd = 1.20–1.35) and 30,50-tpyH (Dd = 0.33–0.54), respec-
tively. Moreover, complex 44 revealed notable downfield shifts
for 4,6-BenH (Dd = 0.62) and 2-BenH (Dd = 0.77). The
structure of 40[(PF6)2] was further confirmed with HRMS by
Fig. 4 (A) Single-crystal X-ray structure of 38[(PF6)2] (atoms drawn
at 50% probability), (B) its space filling model, and (C) molecular
ꢂ
packing (along c axis); MeCN and PF6 are omitted for clarity.
the unique signal at m/z 529.0571 corresponding to [M ꢂ 2PF6]2+
,
and isotope patterns of the peak perfectly matched the
theoretical values. Later, the dinuclear 40 and 44 were hydro-
lyzed by treatment with aqueous NaOH (1 M, excess) in DMF
at 60 1C for 12 h affording sodium carboxylate salts, which
were protonated in the presence of TFA to give carboxylic
acid functionalized complexes 41 and 45 in 490% yield. The
1H NMR spectra of these acids were identical to their starting
ester complexes except they did not contain proton peaks for
CO2CH2CH3. The UV-Vis spectra of dinuclear complexes 40,
41, 44 and 45 displayed the characteristic MLCT peak at
ca. 501–507 nm in MeCN at 25 1C.
The initial attempt to prepare the dinuclear complex 42
containing two free terpyridinyl moieties via Pd[0]-coupling
strategy was unsuccessful (Scheme 6). The terpyridine 17
containing a free acetylene group was intended to couple with
bis-iodo functionality of dinuclear 40 in the presence of
Pd(PPh3)4/CuI in THF/MeCN/NEt3 under argon; however,
the free acetylene of 17 coupled via CuI catalysis with another
acetylene of 17 to give the bis(terpyridine) 43 in 64% yield and
unreacted starting material 40. The 1H NMR spectrum of
bis(terpyridine) 43 displayed similar proton resonances to that
of starting ligand 17, except lacking an acetylenic proton. The
structure of 43 was further confirmed via HRMS by the unique
signal at m/z = 1181.4253 corresponding to [M + H]+.
The construction of dinuclear 46, which was functionalized
with two terpyridinyl moieties, was achieved by treating the
dinuclear 44 with two equivalents of ligand 20 in presence of
Pd(PPh3)4 in DMF/NEt3. Copper catalysis (CuI) was inten-
tionally omitted to circumvent the acetylene-acetylene
coupling of the ligand 20. The separation of dinuclear 46 from
other by-products was accomplished by loading the con-
centrated reaction mixture on a preparative TLC plate (SiO2)
Fig.ꢂ5 Molecular packing of crystals of 38 (along b axis); MeCN and
PF6 are omitted for clarity.
The UV-Vis spectra of tetramethyl Ru(II)-complex 33 dis-
played the characteristic MLCT peak at 493 nm; whereas, the
MLCT for carbonyl Ru(II)-complexes 35–39 appeared at
503 nm in MeCN at 25 1C (Fig. 6). These absorptions lie in
Fig. 6 UV-Vis spectra of Fe(II)-terpyridine complexes 33–39 in
MeCN at 25 1C.
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Scheme 6 Synthesis of dinuclear Ru(II) 40 and 41 and bis(terpyridine) 43. Reagents and conditions: (i) N-ethylmorpholine, EtOH, 70 1C, 24 h, then
NH4PF6; (ii) NaOH (1 M), DMF, 60 1C, 12 h, TFA; (iii) 17, Pd(PPh3)4, CuI, THF/MeCN/NEt3, 70 1C, 12 h, argon.
eluting with a solvent mixture of MeCN–sat. KNO3 (aq)–H2O
(7 : 1 : 1). The darkest band (3rd line from the top) was removed
from the plate and washed with the eluting solvent, followed by
counterion exchange by the addition of excess NH4PF6 (1 M) to
afford the desired dinuclear 46[(PF6)4] in 35% yield (Scheme 7).
The self-assembly of hexanuclear macrocycle 47[(PF6)12] was
achieved by treating the trimer 46[(PF6)4] with an equimolar
amount of FeCl2ꢁ4H2O in EtOH and acetone (Scheme 7). The
macrocycle 47 was obtained in 24% yield after purifying with a
preparative TLC plate (SiO2) eluting with a solvent mixture of
MeCN–sat. KNO3 (aq)–H2O (7 : 1 : 1). This heteronuclear
macrocycle contains four Ru(II) and two Fe(II) metals with eight
methyl and eight ethoxycarbonyl groups. The 1H NMR of the
macrocycle 47 displayed three sets of terpyridine proton
resonances with 5,500-terpyridine proton integration ratio of
1 : 1 : 1 and did not contain any free terpyridine proton peaks.
Further, 6,600-tpy3H and 30,50-tpy3H protons of 47 displayed
the characteristic upfield (Dd = 0.65) and downfield shifts
(Dd = 0.39), respectively, compared to the dinuclear 46
(Fig. 7). The UV-Vis spectrum of the macrocycle 47 further
confirmed the proposed structure by revealing two different
1
The H NMR of the bis(RuII) trimer 46 displayed three sets of
terpyridine proton resonances, two for complexed terpyridines
and one for free terpyridine, with a 1 : 1 : 1 5,500-terpyridine
proton integration ratio confirming the two iodo-acetylene cou-
plings (Fig. 6B). The 2D correlation NMR experiments (COSY)
were conducted to ensure the proper assignments. The first band
from the preparative TLC plate was also collected and found to
be a mono-coupling product in 24% yield rationalizing the poor
yield of the trimer 46. The UV-Vis spectra of trimer 46 displayed
the characteristic MLCT peak at 508 nm in MeCN at 25 1C,
which is similar to dinuclear 44 (507 nm).
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Scheme 7 Synthesis of dinuclear Ru(II) 44–46, and hexanuclear Ru(II)-Fe(II) 47. Reagents and conditions: (i) N-ethylmorpholine, EtOH, 70 1C, 9 h;
(ii) NaOH (1 M), DMF, 60 1C, 12 h, TFA; (iii) 20, Pd(PPh3)4, DMF/NEt3, 70 1C, 48 h, argon, then NH4PF6; (iv) FeCl2ꢁ4H2O, EtOH/acetone,
60 1C, 20 h, then NH4PF6.
MLCT absorptions for Ru(II) and Fe(II) at 511 and 569 nm,
respectively, in MeCN at 25 1C. The absorbance ratio of
Ru(II)-MLCT (511 nm)/Fe(II)-MLCT (569 nm) is 2.42
suggesting the 4.8 : 2 metal ratio in the macrocycle 47.
to investigate their solar cell applications and supramolecular
aggregation behavior through hydrogen-bonding.
Experimental
Conclusions
General comments
The 4,400-dimethyl functionalized bis(terpyridine)s 8 and 9
Melting point data were obtained in capillary tubes with
an Electrothermal 9100 melting point apparatus and are
uncorrected. All chemicals were purchased from Aldrich
Co. Tetrahydrofuran (THF) was dried by refluxing over
benzophenone/Na under N2. Dichloromethane was dried over
CaH2. All other commercially available solvents were used
without further purification. Column chromatography was
conducted using silica gel (60–200 mesh) from Fisher Scientific
were synthesized via the Krohnke method and a single crystal
¨
X-ray structure of 9 was obtained. A novel 4,400-di(ethoxy-
carbonyl) functionalized bis(terpyridine) 15 was prepared via
Pd[0]-mediated cross-coupling method. The synthesis of hetero-
leptic Ru(II) complex 36 was accomplished in a quantitative
yield; whereas, homoleptic complexes 34 and 38 were obtained
in only moderate yields. The single-crystal X-ray structure of
the homoleptic complex 38 revealed iodo-carbonyl inter-
actions. The high yield complexation reactions of the carbonyl-
functionalized metalated adduct 32 with methyl substituted
mono- and bis-terpyridines were adapted, as a main strategy,
to construct a bis-iodo functionalized dinuclear 44, which was
coupled with terpyridine 20 containing a free acetylene group to
form the dinuclear trimer 46. The heteronuclear (Ru4Fe2)
metallomacrocycle 47 was finally assembled by treatment of
the trimer 46 with an equimolar amount of FeCl2ꢁ4H2O. The
carboxylic acid functionalized Ru(II) complexes were prepared
1
with the stipulated solvent mixture. H and 13C NMR spectra
were obtained in CDCl3, except where noted, and are recorded
at 250 and 52 MHz, respectively. Infrared spectra (IR) were
obtained (KBr pellet, unless otherwise noted) and recorded on
an ATI Mattson Genesis Series FTIR spectrometer. Mass
spectral data were obtained using an Esquire electrospray
ionization mass spectrometer (ESI) and are reported as: (assign-
ment, relative intensity); ESI samples were typically prepared in
MeOH–H2O–TFA (70 : 30 : 01) for positive ion mode or
Me2CHOH–H2O–NH3 (70 : 30 : 1) for negative ion mode
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1
Fig. 7 Aromatic region of H NMR (300 MHz) of (A) 47[(PF6)12] and (B) 46[(PF6)4] in CD3CN at 25 1C.
and matrix assisted laser desorption ionization time-of-flight
(MALDI-ToF) mass spectrometry.
149.12, 155.86, 156.48; HRMS (calc.): m/z = 675.1850
(675.1866, [M + H]+).
The crystal structures were collected on a Bruker Apex CCD
diffractometer with graphite-monochromated Mo-Ka radia-
tion (l = 0.71073 A). The reflections from three different
orientations were used to determine the unit cell. Multi-scan
SADABS was used to make corrections. The Bruker
SHELXTL computer program was used to solve structures,
refine, and model. The structures were obtained by full-matrix
least-squares refinement of F2 and the selection of appropriate
atoms from the generated difference map.
1,3-Bis(4,400-dimethyl-2,20:60,200-terpyridin-40-yl)-5-methylbenzene,
9. To a stirred solution of 5 (208 mg, 1.41 mmol) and 2-acetyl-
4-methylpyridine (800 mg, 5.91 mmol) in EtOH (50 mL) at 25 1C,
aqueous NaOH (1 M, 6 mL) was added. Following the above
procedure for 8, after chromatography, the desired product 9 was
isolated as a white solid: 50 mg (6%); mp 258–260 1C. 1H NMR
d 2.54 (s, 12 H, tpyCH3), 2.56 (s, 3 H, BenCH3), 7.20 (d, 4 H,
5,500-tpyH, J = 4.5 Hz), 7.8 (s, 2 H, 4,6-BenH), 8.15 (s, 1 H,
2-BenH), 8.52 (s, 4 H, 3,300-tpyH), 8.61 (d, 4 H, 6,600-tpyH, J =
4.8 Hz), 8.78 (s, 4 H, 30,50-tpyH); 13C NMR d 21.58, 29.89, 119.6,
122.41, 123.69, 125.03, 129.03, 139.51, 139.62, 148.32, 149.12,
150.44, 156.2, 156.28. Crystal data for 9: C41H34N6, M =
610.74 amu, orthorhombic, Pbca, a = 11.800(3), b = 13.208(3),
Syntheses
3,5-Bis(4,400-dimethyl-2,20:60,200-terpyridin-40-yl)-1-bromobenzene,
8. To a stirred solution of 3 (2.02 g, 9.48 mmol) and 2-acetyl-
4-methylpyridine (5.31 g, 39.3 mmol) in EtOH (300 mL) at
25 1C, aqueous NaOH (4 M, 10 mL) was added. The mixture
was stirred for 9 h at 25 1C, then concentrated in vacuo to yield
a dark brown diketone intermediate 6. To a stirred solution of
intermediate 6 in AcOH (50 mL), NH4OAc (30 g, excess) was
added and the mixture was refluxed for 11 h. The solution was
concentrated in vacuo to give a paste, which was neutralized
with Na2CO3 (1 M) and extracted with CHCl3. The combined
extract was dried (MgSO4) and then evaporated in vacuo to
give a residue that was column chromatographed (basic
Al2O3) eluting with EtOAc–hexane mixture (1 : 1) to give 8,
as a light yellow solid: 820 mg (13%); mp 317–319 1C. 1H
NMR d 2.54 (s, 12 H, tpyCH3), 7.20 (d, 4 H, 5,500-tpyH, J =
4.8 Hz), 8.1 (d, 2 H, 2,6-BenH, J = 1.2 Hz), 8.24 (s, 1 H,
4-BenH), 8.5 (s, 4 H, 3,300-tpyH), 8.61 (d, 4 H, 6,600-tpyH, J =
4.8 Hz), 8.74 (s, 4 H, 30,50-tpyH); 13C NMR d 21.53, 119.31,
122.31, 123.81, 124.82, 125.12, 130.84, 141.55, 148.23, 148.66,
c = 41.505(9) A, V = 6469(2) A3, Z = 8, Dc = 1.254 Mg mꢂ3
,
m = 0.075 mmꢂ1, F(000) = 2576, Final R indices (for 4792
reflections) [I 4 2s(I)] were R1 = 0.0725, and R1 = 0.0990,
wR2 = 0.1614 for all 38777 data.
1-(Trimethylsilyl)ethynyl-3-ethynyltoluene, 11. To a stirred
solution of 10 (600 mg, 4.28 mmol) in dry THF (30 mL) under
N2 at ꢂ78 1C, n-BuLi (2.5 M, 1.8 mL, 4.5 mmol) was added
dropwise. The solution was stirred at ꢂ78 1C for 2 h, and then
trimethylsilyl chloride (697 mg, 6.42 mmol) was added quickly.
The reaction mixture was warmed to 25 1C and stirred over-
night. The solution was concentrated in vacuo to give an oily
residue that was column chromatographed (SiO2) eluting with
1
hexane to give 11, as a colorless oil: 409 mg (45%); H NMR
d 0.27 (s, 9 H, (CH3)3Si), 2.30 (s, 3 H, BenCH3), 3.05 (s, 1 H,
CRC–H), 7.25 (s, 1 H, 4-BenH), 7.27 (s, 1 H, 2-BenH), 7.43
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(s, 1 H, 6-BenH); 13C NMR d 0.11, 21.11, 77.57, 83.09, 94.79,
104.39, 122.39, 123.48, 132.84, 132.95, 133.1, 138.31.
(t, 6 H, tpyCO2CH2CH3, J = 7.2 Hz), 2.32 (s, 3 H, BenCH3),
4.47 (q, 4 H, tpyCO2CH2CH3, J = 7.2 Hz), 7.26 (s, 1 H,
4-BenH), 7.31 (s, 1 H, 2-BenH), 7.59 (s, 1 H, 6-BenH), 7.62 (d, 2
H, 3,5-ArH, J = 8.1 Hz), 7.85 (m, 4 H, 2,6-ArH, 5,500-tpyH),
8.68 (s, 2 H, 30,50-tpyH), 8.8 (d, 2 H, 6,600-tpyH, J1 = 4.8 Hz),
9.13 (s, 2 H, 3,300-tpyH); 13C NMR d 0.12, 14.41, 21.17, 61.97,
89.4, 90.48, 94.75, 104.51, 119.16, 120.88, 123.11, 123.28,
123.49, 124.2, 127.29, 132.35, 132.41, 132.46, 132.74, 137.89,
138.37, 138.97, 149.38, 149.94, 155.53, 157.11, 165.37; HRMS
(calc.): m/z = 664.2638 (664.2631, [M + H]+).
1,3-Bis(2,20;60,200-terpyridinyl-40-phen-4-ylethynyl)toluene, 14.
To a stirred solution of 12 (1.77 g, 4.06 mmol) in THF
(50 mL) and NEt3 (50 mL), 10 (250 mg, 1.78 mmol) was
added. The mixture was degassed and back-filled with argon
(three times) then Pd(PPh3)4 (207 mg, 180 mmol, 5% per
coupling site) and CuI (27 mg, 150 mmol) were added, then
stirred for 12 h at 70 1C. The mixture was filtered and washed
with THF (20 mL). The filtrate was concentrated in vacuo to
give a residue that was column chromatographed (basic
Al2O3) eluting with CHCl3 to give 14, as a light yellow solid:
1.14 g (85%); mp 178–179 1C; 1H NMR d 2.4 (s, 3 H,
1-[4,400-Di(ethoxycarbonyl)-2,20;60,200-terpyridinyl-40-phen-4-
ylethynyl]-3-ethynyltoluene, 17. To a stirried solution of 16
(170 mg, 256 mmol) in THF (20 mL) and EtOH (20 mL), KF
(24 mg, 413 mmol) was added then the mixture was stirred for
10 h at 25 1C. Solution was concentrated in vacuo to give a
residue that was column chromatographed (Al2O3) eluting
with CHCl3 to give 17, as a white solid: 139 mg (92%); mp
237–238 1C; 1H NMR d 1.5 (t, 6 H, tpyCO2CH2CH3, J =
7.2 Hz), 2.32 (s, 3 H, BenCH3), 3.1 (s, 1 H, CRC–H), 4.48
(q, 4 H, tpyCO2CH2CH3, J = 7.2 Hz), 7.28 (s, 1 H, 4-BenH),
7.35 (s, 1 H, 2-BenH), 7.5 (s, 1 H, 6-BenH), 7.64 (d, 2 H,
3,5-ArH, J = 8.1 Hz), 7.88 (m, 4 H, 2,6-ArH, 5,500-tpyH), 8.72
(s, 2 H, 30,50-tpyH), 8.83 (d, 2 H, 6,600-tpyH, J1 = 4.8 Hz), 9.16
(s, 2 H, 3,300-tpyH); 13C NMR d 14.43, 21.19, 61.99, 77.68,
83.12, 89.53, 90.33, 119.24, 120.92, 122.51, 123.15, 123.41,
124.15, 127.34, 132.4, 132.5, 132.82, 132.94, 138.02, 138.52,
139.02, 149.46, 149.97, 155.6, 157.15, 165.41; HRMS (calc.):
m/z = 592.2233 (592.2236, [M + H]+).
BenCH3), 7.36 (dd, 4 H, 5,500-tpyH, J1 = 4.8 Hz, J2
=
1.2 Hz), 7.39 (s, 2 H, 2,4-BenH), 7.62 (s, 1 H, 6-BenH), 7.70
(d, 4 H, 3,5-ArH, J = 8.4 Hz), 7.89 (td, 4 H, 4,400-tpyH, J1 =
7.5 Hz, J2 = 1.8 Hz), 7.92 (d, 4 H, 2,6-ArH, J = 8.4 Hz), 8.7
(dt, 4 H, 3,300-tpyH, J1 = 7.8 Hz, J2 = 0.9 Hz), 8.74 (dd, 4 H,
6,600-tpyH, J1 = 4.8 Hz, J2 = 0.9 Hz), 8.77 (s, 4 H, 30,50-tpyH);
13C NMR d 21.3, 89.62, 90.43, 118.86, 121.58, 123.55, 124.1,
127.5, 132.14, 132.42, 132.5, 137.1, 138.47, 138.6, 149.36,
149.55, 156.26, 156.35; HRMS (calc.): m/z = 755.2910
(755.2923, [M + H]+).
1,3-Bis[4,400-di(ethoxycarbonyl)-2,20;60,200-terpyridinyl-40-phen-
4-ylethynyl]toluene, 15. To a stirred solution of diester 13
(643.3 mg, 1.11 mmol) in THF (70 mL) and diisopropylamine
(25 mL), 10 (66.6 mg, 475 mmol) was added. The mixture was
degassed and back-filled with argon (three times), then
Pd(PPh3)4 (44 mg, 38 mmol, 4% per coupling site) and CuI
(5.2 mg, 27 mmol) was added to the flask, then stirred for 12 h
at 70 1C. The mixture was filtered and washed with THF
(20 mL). The filtrate was concentrated in vacuo to give a
residue that was column chromatographed (basic Al2O3)
eluting with CHCl3 to give 15, as a light yellow solid:
431 mg (87%); mp 314–315 1C; 1H NMR d 1.51 (t, 12 H,
tpyCO2CH2CH3, J = 7.2 Hz), 2.4 (s, 3 H, BenCH3), 4.5 (q, 8
H, tpyCO2CH2CH3, J = 7.2 Hz), 7.39 (s, 2 H, 2,4-BenH), 7.62
(s, 1 H, 6-BenH), 7.71 (d, 4 H, 3,5-ArH, J = 8.7 Hz), 7.94
(m, 8 H, 2,6-ArH, 5,500-tpyH), 8.8 (s, 4 H, 30,50-tpyH),
8.88 (dd, 4 H, 6,600-tpyH, J1 = 5.1 Hz, J2 = 0.9 Hz), 9.22
(s, 4 H, 3,300-tpyH); 13C NMR d 14.46, 21.3, 62.04, 89.55,
90.57, 119.37, 121.01, 123.22, 123.51, 124.31, 127.44,
132.14, 132.48, 138.1, 138.61, 139.12, 149.65, 150.03, 155.7,
157.24, 165.47; HRMS (calc.): m/z = 1043.3726 (1043.3768,
[M + H]+).
40-(3-Iodophenyl)-2,20;60,200-terpyridine, 18. To
a stirred
solution of 3-iodobenzaldehyde (2.54 g, 10.9 mmol) and
2-acetylpyridine (2.98 g, 24.6 mmol) in EtOH (250 mL) at
25 1C, aqueous NaOH (1 M, 22 mL) was added. The mixture
was stirred for 9 h at 25 1C then concentrated in vacuo to yield
a dark brown diketone intermediate. To a stirred solution of
this intermediate in AcOH (80 mL), NH4OAc (13 g, excess)
was added and the mixture was refluxed for 11 h. Solution was
concentrated in vacuo to give a paste, which was neutralized
with Na2CO3 (1 M) and extracted with CHCl3. Organic
layers were combined, dried (MgSO4) and then the solvent
was evaporated in vacuo to give a residue that was column
chromatographed (basic Al2O3) eluting with an EtOAc–
hexane mixture (1 : 1) to give 18, as a white solid: 1.6 g
1
(34%); mp 156–158 1C; H NMR d 7.24 (t, 1 H, 5-ArH, J =
8.1 Hz), 7.35 (ddd, 2 H, 5,500-tpyH, J1 = 7.5 Hz, J2 = 4.8 Hz,
J3 = 1.2 Hz), 7.77 (ddd, 1 H, 4-ArH, J1 = 7.8 Hz, J2
=
1.8 Hz, J3 = 0.9 Hz), 7.83 (ddd, 1 H, 6-ArH, J1 = 7.5 Hz,
J2 = 1.5 Hz, J3 = 0.9 Hz), 7.88 (td, 2 H, 4,400-tpyH, J1 =
7.5 Hz, J2 = 1.5 Hz), 8.23 (t, 1 H, 2-ArH, J 1.8 Hz), 8.65 (dt, 2 H,
3,300-tpyH, J1 = 8.1 Hz, J2 = 1.2 Hz), 8.68 (s, 2 H, 30,50-tpyH),
8.73 (ddd, 2 H, 6,600-tpyH, J1 = 4.8 Hz, J2 = 1.8 Hz, J3 =
0.9 Hz); 13C NMR d 95.04, 118.95, 121.58, 124.15, 126.87,
130.75, 136.27, 137.1, 138.11, 140.92, 148.83, 149.97, 156.2,
156.25; HRMS (calc.): m/z = 458.0122 (458.0130, [M + Na]+).
1-[4,400-Di(ethoxycarbonyl)-2,20;60,200-terpyridinyl-40-phen-4-
ylethynyl]-3-[(trimethylsilyl)ethynyl]toluene, 16. To a stirred
solution of diester 13 (234 mg, 400 mmol) in THF (60 mL)
and NEt3 (60 mL), 11 (85 mg, 400 mmol) was added. The
mixture was degassed and back-filled with argon (three times),
then Pd(PPh3)4 (34 mg, 29.4 mmol, 7% per coupling site) and
CuI (8 mg, 42 mmol) were added to the flask, then stirred for
12 h at 70 1C. The mixture was filtered and washed with THF
(20 mL). The filtrate was concentrated in vacuo to give a
residue that was column chromatographed (basic Al2O3)
eluting with CHCl3 to give 16, as a light yellow solid: 220 mg
(83%); mp 247–248 1C; 1H NMR d 0.26 [s, 9 H, (CH3)3Si], 1.48
40-[3-(Trimethylsilyl)ethynylphenyl]-2,20;60,200-terpyridine, 19.
To a stirred solution of 18 (1.53 g, 3.48 mmol) in THF
(120 mL) and NEt3 (90 mL), trimethylsilylacetylene (662 mg,
6.74 mmol) was added. The mixture was degassed and
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New J. Chem., 2009, 33, 345–357 | 353

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back-filled with argon (three times) then Pd(PPh3)4 (238 mg,
206 mmol, 6% per coupling site) and CuI (37.7 mg, 197 mmol)
was added to the flask and the mixture was degassed and back-
filled with argon (two times) then stirred for 12 h at 70 1C. The
mixture was filtered and washed with THF (20 mL). The
filtrate was concentrated in vacuo to give a residue that was
column chromatographed (basic Al2O3) eluting with CHCl3 to
give 19, as a white solid: 1.2 g (85%); mp 141–143 1C; 1H
NMR d 0.3 [s, 9 H, (CH3)3Si], 7.37 (dd, 2 H, 5,500-tpyH, J1 =
5.7 Hz, J2 = 1.5 Hz), 7.46 (t, 1 H, 5-ArH, J = 7.8 Hz), 7.55
(d, 1 H, 4-ArH, J = 7.5 Hz), 7.85 (d, 1 H, 6-ArH, J = 7.5 Hz),
7.90 (td, 2 H, 4,400-tpyH, J1 = 7.8 Hz, J2 = 1.5 Hz), 8.03
(s, 1 H, 2-ArH), 8.67 (d, 2 H, 3,300-tpyH, J = 8.1 Hz), 8.73
(s, 2 H, 30,50-tpyH), 8.76 (d, 2 H, 6,600-tpyH, J = 4.8 Hz); 13C
NMR d 0.19, 95.15, 104.82, 119.18, 121.72, 124.18, 127.7,
129.1, 131.01, 132.63, 137.35, 138.76, 149.15, 149.79,
155.99, 156.11; HRMS (calc.): m/z = 428.1563 (428.1559,
[M + Na]+).
NMR (CD3CN) d 21.12, 122.43, 122.55, 125.46, 126.37,
126.52, 128.84, 129.89, 131.03, 134.14, 137.28, 140.12,
151.03, 153.06, 153.36, 154.14, 159.07, 159.77, 162.1, 162.18;
HRMS (calc.): m/z = 430.0191 (430.0190, [M ꢂ 2PF6]2+).
27[(Cl)2]. To a stirred solution of 23 (164.3 mg, 397 mmol) in
MeOH (60 mL), FeCl2ꢁ4H2O (39.5 mg, 198 mmol) was added
then refluxed for 20 h. The solution was concentrated in vacuo
and dried to give 27, as a purple solid: 178 mg (94%); 1H
NMR (CD3OD) d 7.22 (t, 2 H, 500-tpyH, J = 6.0 Hz), 7.3 (d, 2
H, 600-tpyH, J = 5.4 Hz), 7.48 (d, 2 H, 5-tpyH, J = 5.1 Hz),
7.53 (d, 2 H, 6-tpyH, J = 5.7 Hz), 7.98 (d, 4 H, 3,5-ArH, J =
8.1 Hz), 8.03 (t, 2 H, 400-tpyH, J = 7.8 Hz), 8.33 (d, 4 H,
2,6-ArH, J = 8.4 Hz), 8.86 (d, 2 H, 300-tpyH, J = 7.8 Hz), 9.25
(s, 2 H, 3-tpyH), 9.51 (s, 2 H, 50-tpyH), 9.58 (s, 2 H, 30-tpyH);
ESI-MS (calc.): m/z
=
441.0 (441.0, [M
ꢂ
2Cl]2+);
MALDI-TOF (calc.): m/z = 882.342 (881.998, [M ꢂ 2Cl]2+).
28[(Cl)2]. To a stirred solution of 24 (100.1 mg, 224 mmol) in
MeOH (50 mL), FeCl2ꢁ4H2O (22.2 mg, 112 mmol) was added
then refluxed for 8 h. The solution was concentrated in vacuo
and dried to give 28, as a purple solid: 108 mg (95%); 1H
NMR (CD3OD) d 3.94 (s, 6 H, tpyCO2CH3), 7.21 (t, 2 H,
500-tpyH, J = 6.0 Hz), 7.31 (d, 2 H, 600-tpyH, J = 5.1 Hz),
7.52 (d, 2 H, 5-tpyH, J = 5.7 Hz), 7.62 (d, 2 H, 6-tpyH, J =
5.4 Hz), 7.99 (d, 4 H, 3,5-ArH, J = 8.1 Hz), 8.01 (t, 2 H,
400-tpyH, J = 7.8 Hz), 8.37 (d, 4 H, 2,6-ArH, J = 8.4 Hz),
8.87 (d, 2 H, 300-tpyH, J = 7.8 Hz), 9.29 (s, 2 H, 3-tpyH),
9.5 (s, 2 H, 50-tpyH), 9.62 (s, 2 H, 30-tpyH); ESI-MS (calc.):
m/z = 473.0 (473.0, [M ꢂ 2Cl]2+); MALDI-TOF (calc.):
m/z = 948.276 (948.018, [M ꢂ 2Cl]2+), 860.117 (860.038,
[M ꢂ 2Cl ꢂ 2CO2]2+).
40-(3-Ethynylphenyl)-2,20;60,200-terpyridine, 20. To a stirred
solution of 19 (420 mg, 1.04 mmol) in THF (30 mL),
(n-Bu)4NFꢁ3H2O (500 mg, 1.59 mmol) was added, then the
mixture was stirred for 6 h at 25 1C. Solution was concentrated
in vacuo to give a residue that was column chromatographed
(Al2O3) eluting with CHCl3 to give 20, as a light yellow solid:
330 mg (95%); mp 173–175 1C; 1H NMR d 3.16 (s, 1 H,
ArCRC–H), 7.37 (dd, 2 H, 5,500-tpyH, J1 = 5.7 Hz, J2 =
1.5 Hz), 7.47 (t, 1 H, 5-ArH, J = 7.8 Hz), 7.57 (d, 1 H, 4-ArH,
J = 7.8 Hz), 7.88 (m, 3 H, 6-ArH, 4,400-tpyH), 8.05 (s, 1 H,
2-ArH), 8.66 (d, 2 H, 3,300-tpyH, J = 7.8 Hz), 8.72 (s, 2 H,
30,50-tpyH), 8.74 (d, 2 H, 6,600-tpyH, J = 5.1 Hz); 13C NMR d
78.04, 83.45, 119.05, 121.61, 123.06, 124.15, 127.98, 129.18,
131.16, 132.73, 137.22, 138.88, 149.22, 149.49, 156.09; HRMS
(calc.): m/z = 356.1164 (356.1163, [M + Na]+).
31. To a stirred solution of 29 (56 mg, 105 mmol) in EtOH
(10 mL) and THF (30 mL), RuCl3ꢁ3H2O (35.9 mg, 137 mmol)
was added then refluxed for 15 h. After cooling, the mixture
was filtered and washed with EtOH (3 ꢃ 50 mL) and THF
(3 ꢃ 50 mL) to give 31, as a dark red solid: 62 mg (80%).
25[(Cl)2]. To a stirred solution of 21 (63.1 mg, 152 mmol) in
MeOH (50 mL), FeCl2ꢁ4H2O (15.2 mg, 76 mmol) was added
then the mixture was refluxed for 8 h. The solution was
concentrated in vacuo and dried to give 25, as a purple solid:
69.6 mg (95%); 1H NMR (CD3OD) d 2.46 (s, 12 H, tpyCH3),
7.03 (d, 4 H, 5,500-tpyH, J = 5.1 Hz), 7.06 (d, 4 H, 6,600-tpyH,
J = 5.4 Hz), 7.97 (d, 4 H, 3,5-ArH, J = 8.1 Hz), 8.35
(d, 4 H, 2,6-ArH, J = 8.1 Hz), 8.76 (s, 4 H, 3,300-tpyH), 9.43
(s, 4 H, 30,50-tpyH); HRMS (calc.): m/z = 444.0342 (444.0347,
[M ꢂ 2Cl]2+).
32. To a stirred solution of 13 (331 mg, 571 mmol) in EtOH
(25 mL) and THF (75 mL), RuCl3ꢁ3H2O (155 mg, 594 mmol)
was added then refluxed for 15 h. After cooling, the mixture
was filtered and washed with EtOH (3 ꢃ 50 mL) and THF
(3 ꢃ 50 mL) to give 32, as a dark red solid: 380 mg (85%).
33[(Cl)2]. To a stirred solution of 21 (103 mg, 247 mmol) in
MeOH (50 mL), RuCl3ꢁ3H2O (32.6 mg, 124 mmol) and
N-ethylmorpholine (6 drops) was added then refluxed for 10 h.
The solution was concentrated in vacuo and dried to give 33, as
26[(PF6)2]. To a stirred solution of 22 (79 mg, 196 mmol) in
MeOH (50 mL), FeCl2ꢁ4H2O (19.6 mg, 98 mmol) was added,
then refluxed for 8 h. The solution was concentrated in vacuo
to give a deep purple precipitate that was column chromato-
graphed (SiO2) eluting with MeCN–sat. KNO3 (aq)–H2O
(7 : 1 : 1) then counterion exchanged by treating with an
excess NH4PF6 (1 M) then dried to give 26, as a purple solid:
89 mg (91%); 1H NMR (CD3CN) d 2.42 (s, 6 H, tpyCH3), 6.94
(d, 2 H, 600-tpyH, J = 5.1 Hz), 6.98 (d, 2 H, 6-tpyH, J =
5.7 Hz), 7.07 (t, 2 H, 500-tpyH, J = 6.9 Hz), 7.16 (d, 2 H,
5-tpyH, J = 5.4 Hz), 7.90 (t, 2 H, 400-tpyH, J = 7.8 Hz), 8.00
(d, 4 H, 3,5-ArH, J = 8.7 Hz), 8.22 (d, 4 H, 2,6-ArH, J =
8.1 Hz), 8.52 (s, 2 H, 3-tpyH), 8.59 (d, 2 H, 300-tpyH, J =
8.1 Hz), 9.13 (s, 2 H, 30-tpyH), 9.15 (s, 2 H, 50-tpyH); 13C
1
a dark red solid: 124 mg (98%); H NMR (CD3OD) d 2.54
(s, 12 H, tpyCH3), 7.15 (d, 4 H, 5,500-tpyH, J = 5.4 Hz), 7.35
(d, 4 H, 6,600-tpyH, J = 5.7 Hz), 7.93 (d, 4 H, 3,5-ArH, J =
8.4 Hz), 8.28 (d, 4 H, 2,6-ArH, J = 8.7 Hz), 8.83 (s, 4 H,
3,300-tpyH), 9.28 (s,
4
H, 30,50-tpyH); HRMS (calc.):
m/z = 467.0196 (467.0198, [M ꢂ 2Cl]2+).
34[(PF6)2]. To a stirred solution of 30 (101.3 mg, 201 mmol)
in MeOH (60 mL), RuCl3ꢁ3H2O (26.1 mg, 100 mmol) and
N-ethylmorpholine (6 drops) was added then the mixture was
refluxed for 20 h. The solution was concentrated in vacuo to
give a red precipitate that was column chromatographed
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354 | New J. Chem., 2009, 33, 345–357

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(SiO2) eluting with MeCN–sat. KNO3 (aq)–H2O (7 : 1 : 1) then
counterion exchanged by treating with an excess NH4PF6 (1
M) and dried to give 34, as a dark red solid: 55 mg (40%); 1H
NMR (CD3CN) d 3.94 (s, 12 H, tpyCO2CH3), 7.6 (s, 8 H, 5,500-
tpyH, 6,600-tpyH), 7.99 (d, 4 H, 3,5-ArH, J = 8.4 Hz), 8.19 (d,
4 H, 2,6-ArH, J = 8.7 Hz), 9.12 (s, 4 H, 3,300-tpyH), 9.21 (s, 4
H, 30,50-tpyH).
20 h. The solution was concentrated in vacuo to give a red
precipitate that was column chromatographed (SiO2) eluting
with MeCN–sat. KNO3 (aq)–H2O (7 : 1 : 1) then counterion
exchanged by treating with an excess NH4PF6 (1 M) followed
1
by drying to give 38, as a dark red solid: 210 mg (55%); H
NMR (CD3CN) d 1.36 (t, 12 H, tpyCO2CH2CH3, J = 6.9 Hz),
4.41 (q, 8 H, tpyCO2CH2CH3, J = 6.9 Hz), 7.6 (s, 8 H,
5,500-tpyH, 6,600-tpyH), 8.06 (d, 4 H, 3,5-ArH, J = 8.7 Hz),
8.16 (d, 4 H, 2,6-ArH, J = 8.4 Hz), 9.1 (s, 4 H, 3,300-tpyH), 9.2
(s, 4 H, 30,50-tpyH); HRMS (calc.): m/z = 630.0170 (630.0177,
[M ꢂ 2PF6]2+). Crystal data for 38: C56H47F12I2N7O8P2Ru;
M = 1590.84 amu (the formula weight does not include
disordered solvent molecules that were removed from the
model; please see Experimental special details in the cif
file, ESIz), orthorhombic, P212121, a = 14.3505(12), b =
14.4204(12), c = 33.419(3) A, V = 6915.8(10) A3, Z = 4,
Dc = 1.528 Mg mꢂ3, m = 1.250 mmꢂ1, F(000) = 3136, Final
R indices (for 16295 reflections) [I 4 2s(I)] were R1 = 0.0467,
and R1 = 0.0630, wR2 = 0.1175 for all 60158 data, Flack
parameter = 0.011(15).
35[(CF3CO2)2]. To a stirred solution of 34[(PF6)2] (27.6 mg,
19.7 mmol) in DMF (15 mL), NaOH (1 M, 5 mL) was added
then the mixture was stirred at 60 1C for 12 h. The solvent was
removed and TFA in MeCN was added, then the solution was
concentrated in vacuo to afford a residue that was washed
with H2O (50 mL) to give 35, as a dark red solid: 24.4 mg
(92%); 1H NMR (CD3CN
(s, 8 H, 5,500-tpyH, 6,600-tpyH), 7.97 (d, 4 H, 3,5-ArH, J =
+
CF3CO2D)
d
7.61
8.1 Hz), 8.19 (d, 4 H, 2,6-ArH, J = 8.74 Hz), 9.14 (s, 4 H,
3,300-tpyH), 9.22 (s,
4
H, 30,50-tpyH); MALDI-TOF
(calc.): m/z = 1054.200 (1053.936, [M ꢂ 2CF3CO2]2+),
1010.215 (1009.946, [M ꢂ 2CF3CO2 ꢂ CO2]2+), 966.225
(965.956, [M ꢂ 2CF3CO2 ꢂ 2CO2]2+), 922.198 (921.966,
3CO2]2+), 878.251 (877.977,
39[(CF3CO2)2]. To a stirred solution of 38[(PF6)2] (75 mg,
48.4 mmol) in DMF (15 mL), NaOH (1 M, 5 mL) was added,
then the mixture was stirred at 60 1C for 12 h. The solvent was
removed and TFA in MeCN was added; the solution was
concentrated in vacuo to afford a residue that was washed
with H2O (50 mL) to give 39, as a dark red solid: 66.1 mg
(95%); 1H NMR (CD3CN + CF3CO2D) d 7.6 (s, 8 H,
5,500-tpyH, 6,600-tpyH), 8.05 (d, 4 H, 3,5-ArH, J = 8.7 Hz),
8.12 (d, 4 H, 2,6-ArH, J = 8.4 Hz), 9.13 (s, 4 H, 3,300-tpyH),
9.21 (s, 4 H, 30,50-tpyH); MALDI-TOF (calc.): m/z =
1148.197 (1147.910, [M ꢂ 2CF3CO2]2+), 1104.278 (1103.920,
[M ꢂ 2CF3CO2 ꢂ CO2]2+), 1060.281 (1059.930, [M ꢂ 2CF3CO2 ꢂ
2CO2]2+), 1016.272 (1015.941, [M ꢂ 2CF3CO2 ꢂ 3CO2]2+),
972.240 (971.951, [M ꢂ 2CF3CO2 ꢂ 4CO2]2+).
[M
ꢂ
2CF3CO2
ꢂ
[M ꢂ 2CF3CO2 ꢂ 4CO2]2+).
36[(Cl)2]. To a stirred solution of 31 (35 mg, 47.4 mmol) and
21 (19.7 mg, 47.3 mmol) in EtOH (20 mL), N-ethylmorpholine
(6 drops) was added then the mixture was refluxed for 10 h. The
solution was concentrated in vacuo and dried to give 36, as a
dark red solid: 53 mg (99%); 1H NMR (CD3OD) d 1.38 (t, 6 H,
tpy1CO2CH2CH3, J = 6.9 Hz), 2.52 (s, 6 H, tpy2CH3), 4.43
(q, 4 H, tpy1CO2CH2CH3, J = 6.9 Hz), 7.11 (d, 2 H,
5,500-tpy2H, J = 5.7 Hz), 7.3 (d, 2 H, 6,600-tpy2H, J = 5.7
Hz), 7.74 (dd, 2 H, 5,500-tpy1H, J1 = 6.0 Hz, J2 = 1.8 Hz),
7.77 (d, 2 H, 6,600-tpy1H, J = 5.7 Hz), 7.93 (dd, 4 H, 3,5-Ar1H,
3,5-Ar2H, J1 = 8.7 Hz, J2 = 0.9 Hz), 8.28 (m, 4 H,
2,6-Ar1H, 2,6-Ar2H), 8.82 (s, 2 H, 3,300-tpy2H), 9.29 (s, 4 H,
30,50-tpy2H, 3,300-tpy1H), 9.43 (s, 2 H, 30,50-tpy1H); HRMS
(calc.): m/z = 524.0260 (524.0261, [M ꢂ 2Cl]2+).
40[(PF6)4]. To a stirred solution of 32 (97.9 mg, 62 mmol) and
14 (46.9 mg, 124 mmol) in EtOH (20 mL), N-ethylmorpholine
(six drops) was added then the mixture was refluxed for
24 h. The solution was concentrated in vacuo to give a red
precipitate, which was column chromatographed (SiO2)
eluting with MeCN: sat. KNO3 (aq): H2O (20 : 1 : 1) then
counterion exchanged by treating with an excess NH4PF6
(1 M) and dried to give 40, as dark red solid: 95 mg (57%);
1H NMR (CD3CN) d 1.37 (t, 12 H, tpy2CO2CH2CH3, J =
6.9 Hz), 2.44 (s, 3 H, BenCH3), 4.39 (q, 8 H, tpy2CO2CH2CH3,
J = 6.9 Hz), 7.21 (t, 4 H, 5,500-tpy1H, J = 6.3 Hz), 7.41
(d, 5 H, 6,600-tpy1H, J = 4.5 Hz), 7.48 (s, 2 H, 2,6-BenH), 7.64
(dd, 4 H, 5,500-tpy2H, J1 = 5.7 Hz, J2 = 1.5 Hz), 7.67 (d, 4 H,
6,600-tpy2H, J = 5.7 Hz), 7.97 (m, 12 H, 4,400-tpy1H, 3,5-Ar1H,
2,6-Ar1H, 6-BenH), 8.14 (d, 4 H, 3,5-Ar2H, J = 8.4 Hz), 8.28
(d, 4 H, 2,6-Ar2H, J = 8.4 Hz), 8.70 (d, 4 H, 3,300-tpy1H, J =
8.1 Hz), 9.07 (s, 4 H, 30,50-tpy1H), 9.11 (s, 4 H, 3,300-tpy2H),
9.18 (s, 4 H, 30,50-tpy2H); HRMS (calc.): m/z = 529.0571
(529.0561, [M ꢂ 4PF6]4+).
37[(CF3CO2)2]. To a stirred solution of 36[(Cl)2] (42 mg,
37.6 mmol) in DMF (15 mL), NaOH (1 M, 5 mL) was added
then the mixture was stirred at 60 1C for 12 h. The solvent was
removed in vacuo and TFA in MeCN was added; the solution
was concentrated in vacuo to afford a residue that was washed
with H2O (50 mL) to give 37, as a dark red solid: 46.3 mg
(96%); 1H NMR (CD3CN + CF3CO2D) d 2.46 (s, 6 H,
tpy2CH3), 7.02 (d, 2 H, 5,500-tpy2H, J = 5.7 Hz), 7.18
(d, 2 H, 6,600-tpy2H, J = 5.7 Hz), 7.61 (s, 4 H, 5,500-tpy1H,
6,600-tpy1H), 7.93 (m,
4 H, 3,5-Ar1H, 3,5-Ar2H), 8.15
(m, 4 H, 2,6-Ar1H, 2,6-Ar2H), 8.55 (s, 2 H, 3,300-tpy2H), 8.98
(s, 2 H, 30,50-tpy2H), 9.11 (s, 2 H, 3,300-tpy1H), 9.17 (s, 2 H,
30,50-tpy1H); MALDI-TOF (calc.): m/z = 994.249 (993.987,
[M ꢂ 2CF3CO2]2+), 979.242 (978.972, [M ꢂ 2CF3CO2 ꢂ CH3]2+),
950.265 (949.998, [M ꢂ 2CF3CO2 ꢂ CO2]2+), 935.347
(934.982, [M ꢂ 2CF3CO2 ꢂ CO2 ꢂ CH3]2+), 906.332
(906.008, [M ꢂ 2CF3CO2 ꢂ 2CO2]2+).
41[(CF3CO2)4]. To a stirred solution of 40[(PF6)4] (27 mg,
10 mmol) in DMF (15 mL), NaOH (1 M, 5 mL) was added
then the mixture was stirred at 60 1C for 12 h. The solvent was
removed in vacuo and TFA in MeCN was added; the solution
38[(PF6)2]. To a stirred solution of 32 (195 mg, 248 mmol) and
13 (144 mg, 249 mmol) in EtOH (20 mL), N-ethyl-morpholine
(6 drops) was added, then the mixture was refluxed for
ꢀc
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New J. Chem., 2009, 33, 345–357 | 355

View Article Online
was concentrated in vacuo to afford a residue that was washed
with H2O (50 mL) to give 41, as a dark red solid: 22 mg (95%);
1H NMR (CD3CN + CF3CO2D) d 2.46 (s, 3 H, BenCH3),
7.20 (t, 4 H, 5,500-tpy1H, J = 6.3 Hz), 7.40 (d, 5 H, 6,600-tpy1H,
J = 4.5 Hz), 7.53 (s, 2 H, 2,6-BenH), 7.62 (dd, 4 H,
5,500-tpy2H, J1 = 5.7 Hz, J2 = 1.5 Hz), 7.66 (d, 4 H, 6,600-
tpy2H, J = 5.7 Hz), 7.98 (m, 12 H, 4,400-tpy1H, 3,5-Ar1H,
2,6-Ar1H, 6-BenH), 8.12 (d, 4 H, 3,5-Ar2H, J = 8.4 Hz), 8.27
(d, 4 H, 2,6-Ar2H, J = 8.4 Hz), 8.71 (d, 4 H, 3,300-tpy1H,
J = 8.1 Hz), 9.07 (s, 4 H, 30,50-tpy1H), 9.14 (s, 4 H,
3,300-tpy2H), 9.20 (s, 4 H, 30,50-tpy2H); MALDI-TOF
(calc.): m/z = 2003.400 (2003.102, [M ꢂ 4CF3CO2]4+),
1961.422 (1961.113, [M ꢂ 4CF3CO2 ꢂ CO2]4+), 1914.445
(s, 12 H, tpy1CH3), 7.17 (d, 4 H, 5,500-tpy1H, J = 5.4 Hz), 7.24
(d, 4 H, 6,600-tpy1H, J = 5.7 Hz), 7.66 (d, 4 H, 5,500-tpy2H, J =
5.7 Hz), 7.67 (d, 4 H, 6,600-tpy2H, J = 5.7 Hz), 8.06 (d, 4 H,
3,5-ArH, J = 8.7 Hz), 8.14 (d, 4 H, 2,6-ArH, J = 8.4 Hz), 8.68
(s, 4 H, 3,300-tpy1H), 72 (s, 2 H, 2,6-BenH), 9.01 (s, 1 H,
4-BenH), 9.14 (s, 4 H, 30,50-tpy2H), 9.20 (s, 4 H, 3,300-tpy2H),
9.25 (s, 4 H, 30,50-tpy1H); MALDI-TOF (calc.): m/z =
1924.421 (1923.994, [M ꢂ 4CF3CO2]4+), 1880.342 (1880.004,
[M ꢂ 4CF3CO2–CO2]4+).
46[(PF6)4]. To a stirred solution of diester 45[(PF6)4]
(102 mg, 51 mmol) in DMF (30 mL), and NEt3 (30 mL), 20
(41 mg, 123 mmol) was added. The mixture was degassed and
back-filled with argon (three times) then Pd(PPh3)4 (9.5 mg,
8.2 mmol, 8% per coupling site) was added to the flask then
stirred for 2 days at 70 1C. The mixture was concentrated
in vacuo to give a red solution that was loaded on a TLC plate
(SiO2) eluting with MeCN–sat. KNO3 (aq)–H2O (7 : 1 : 1), the
third band (darkest) were removed from the plate and washed
with an eluting solvent, followed by counterion exchange by
the addition of excess NH4PF6 (1 M) to give 46, as a dark red
solid: 55 mg (35%); 1H NMR (CD3CN) d 1.38 (t, 12 H,
tpy2CO2CH2CH3, J = 7.2 Hz), 2.52 (s, 12 H, tpy1CH3),
4.41 (q, 8 H, tpy2CO2CH2CH3, J = 7.2 Hz), 7.08 (d, 4 H,
5,500-tpy1H, J = 5.1 Hz), 7.27 (d, 4 H, 6,600-tpy1H, J = 5.7 Hz),
7.47 (t, 4 H, 5,500-tpy3H, J = 5.4 Hz), 7.70 (d, 4 H, 5,500-tpy2H,
J = 5.7 Hz), 7.74 (d, 4 H, 6,600-tpy2H, J = 6.0 Hz), 7.9
(m, 6 H, 4,400-tpy3H, 5-Ar2H), 8.03 (m, 6 H, 3,5-Ar1H,
4-Ar2H), 8.24 (m, 6 H, 3,300-tpy3H, 6-Ar2H), 8.41 (d, 4 H,
2,6-Ar1H, J = 8.1 Hz), 8.5 (s, 2 H, 2-Ar2H), 8.71 (s, 2H,
2,6-BenH), 8.76 (s, 4 H, 30,50-tpy3H), 8.6 (d, 4 H, 6,600-tpy3H,
J = 8.1 Hz), 9.09 (s, 5 H, 3,300-tpy1H, 4-BenH), 9.16 (s, 4 H,
(1914.124, [M
(1872.130, [M
ꢂ
ꢂ
4CF3CO2
4CF3CO2
ꢂ
ꢂ
2CO2]4+), 1872.485
3CO2]4+), 1831.518
(1831.144, [M ꢂ 4CF3CO2 ꢂ 4CO2]4+).
43. To a stirred solution of diester 40[(PF6)4] (104 mg,
40 mmol) in a THF (30 mL), MeCN (30 mL) and NEt3
(50 mL) solvent mixture, 17 (59 mg, 100 mmol) was added.
The mixture was degassed and back-filled with argon (three
times), then Pd(PPh3)4 (10.1 mg, 8.7 mmol, 10% per coupling
site) and CuI (1.4 mg, 7.3 mmol) were added, then stirred for
12 h at 70 1C. After concentration in vacuo and washing with
MeCN, the residue was column chromatographed (basic
Al2O3) eluting with CHCl3 to give 43, as a yellow solid:
36 mg (64%); mp 275–277 1C; 1H NMR d 1.51 (t, 12 H,
tpyCO2CH2CH3, J = 6.9 Hz), 2.38 (s, 6 H, BenCH3), 4.51
(q, 8 H, tpyCO2CH2CH3, J = 6.9 Hz), 7.35 (s, 2 H, 4-BenH),
7.41 (s, 2 H, 2-BenH), 7.57 (s, 2 H, 6-BenH), 7.71 (d, 4 H,
3,5-ArH, J = 7.8 Hz), 7.94 (m, 8 H, 2,6-ArH, 5,500-tpyH), 8.8
(s, 4 H, 30,50-tpyH), 8.88 (d, 4 H, 6,600-tpyH, J = 4.8 Hz), 9.23
(s, 4 H, 3,300-tpyH); HRMS (calc.): m/z = 1181.4253
(1181.4238, [M + H]+). The MeCN filtrate was concentrated
in vacuo to afford a red microcrystalline solid, which is the
starting material, dinuclear 40[(PF6)4] (95 mg).
30,50-tpy1H), 9.26 (s,
4 4 H,
H, 3,300-tpy2H), 9.32 (s,
30,50-tpy1H); MALDI-TOF (calc.): m/z = 2736.004 (2736.481,
[M ꢂ 2PF6]2+), 2593.831 (2593.519, [M ꢂ 3PF6]3+).
44[(Cl)4]. To a stirred solution of 32 (128 mg, 162.6 mmol) and
8 (54.9 mg, 81.3 mmol) in EtOH (80 mL), N-ethylmorpholine
(six drops) was added, then the mixture was refluxed for
9 h. The solution was concentrated in vacuo and dried to give
44, as a dark red solid: 174 mg (98%); 1H NMR d 1.4 (t, 12 H,
tpy2CO2CH2CH3, J = 7.2 Hz), 2.58 (s, 12 H, tpy1CH3), 4.46
(q, 8 H, tpy2CO2CH2CH3, J = 7.2 Hz), 7.14 (d, 4 H, 5,500-
tpy1H, J = 5.4 Hz), 7.33 (d, 4 H, 6,600-tpy1H, J = 5.7 Hz), 7.81
(d, 4 H, 5,500-tpy2H, J = 5.7 Hz), 7.88 (d, 4 H, 6,600-tpy2H, J =
5.7 Hz), 8.15 (s, 8 H, 3,5-ArH, 2,6-ArH), 8.82 (s, 2 H, 2,6-
BenH), 9.19 (s, 4 H, 3,300-tpy1H), 9.31 (s, 4 H, 30,50-tpy2H),
9.46 (s, 5 H, 3,300-tpy2H, 4-BenH), 9.72 (s, 4 H, 30,50-tpy1H);
MALDI-TOF (calc.): m/z = 2190.458 (2190.146, [M ꢂ 4Cl +
47[(PF6)12]. To a stirred solution of 46[(PF6)4] (5.6 mg,
1.82 mmol) in EtOH (8 mL) and acetone (10 mL), FeCl2ꢁ4H2O
(370 mg, 1.83 mmol) was added, then the mixture was refluxed for
8 h. The mixture was concentrated in vacuo to give a red solution
that was loaded on a TLC plate (SiO2) eluting with MeCN: sat.
KNO3 (aq): H2O (7 : 1 : 1), the top band was removed from the
plate and washed with an eluting solvent, followed by counter-
ion exchange by the addition of excess NH4PF6 (1 M) to afford
1
the hexanuclear 47[(PF6)12], as a pink solid: 2.4 mg (42%); H
NMR (CD3CN) 1H NMR (CD3CN) d 1.37 (t, 24 H,
tpy2CO2CH2CH3, J = 7.2 Hz), 2.55 (s, 24 H, tpy1CH3), 4.43
(q, 16 H, tpy2CO2CH2CH3, J = 7.2 Hz), 7.06 (d, 8 H,
5,500-tpy1H, J = 6.0 Hz), 7.47 (t, 8 H, 5,500-tpy3H, J = 6.6
Hz), 7.26 (m, 16 H, 6,600-tpy1H, 6,600-tpy3H), 7.70 (d, 8H,
5,500-tpy2H, J = 5.7 Hz), 7.74 (d, 8 H, 6,600-tpy2H, J =
6.0 Hz), 7.98 (m, 16 H, 4,400-tpy3H, 4-Ar2H, 5-Ar2H), 8.06
(d, 8 H, 3,5-Ar1H, J = 8.1 Hz), 8.43 (d, 12 H, 2,6-Ar1H,
6-Ar2H, J = 8.1 Hz), 8.65 (s, 4 H, 2,6-BenH), 8.74 (d, 12 H,
3,300-tpy3H, 2-Ar2H, J = 8.1 Hz), 9.02 (s, 8 H, 3,300-tpy1H),
9.16 (s, 8 H, 3,300-tpy2H), 9.27 (s, 8 H, 30,50-tpy3H), 9.32 (s, 8 H,
30,50-tpy2H), 9.59 (s, 8 H, 30,50-tpy1H). MALDI-TOF (calc.):
m/z = 2593.774 (2593.519, [M ꢂ 11PF6 ꢂ 2Fe]3+), 2466.765
DHB]4+), 2143.432 (2143.027, [M
ꢂ
Cl]+), 2036.611
(2036.119, [M ꢂ 4Cl]4+).
45[(CF3CO2)4]. To a stirred solution of 44[(PF6)4] (34 mg,
15.6 mmol) in DMF (15 mL), NaOH (1 M, 5 mL) was added
then the mixture was stirred at 60 1C for 12 h. The solvent was
removed in vacuo and a solution of TFA in MeCN was added
then the solution was concentrated in vacuo to afford a residue
that was washed with H2O (50 mL) to give 45, as a dark red
solid: 30 mg (98%); 1H NMR (CD3CN + CF3CO2D) 2.55
ꢀc
This journal is The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2009
356 | New J. Chem., 2009, 33, 345–357

View Article Online
(2466.474, [M ꢂ 11PF6 ꢂ PF5 ꢂ 2Fe]4+), 2446.552 (2446.256,
[M ꢂ 12PF6 ꢂ 2Fe]4+).
19 S. A. Sapp, C. M. Elliot, C. Contado, S. Caramori and
C. A. Bignozzi, J. Am. Chem. Soc., 2002, 124, 11215.
20 Z.-S. Wang, T. Yamaguchi, H. Sugihara and H. Arakawa,
Langmuir, 2005, 21, 4272.
21 F. Aiga and T. Tada, Sol. Energy Mater. Sol. Cells, 2005,
85, 437.
22 S.-H. Hwang, C. N. Moorefield, L. A. Godınez, J. Nanriquez,
´
E. Bustos and G. R. Newkome, Chem. Commun., 2005, 4672.
23 C. Mikel and P. G. Potvin, Polyhedron, 2002, 21, 49.
24 G. R. Newkome, T. J. Cho, C. N. Moorefield, G. R. Baker,
M. J. Saunders, R. Cush and P. S. Russo, Angew. Chem., Int.
Ed., 1999, 38, 3717.
Acknowledgements
The authors gratefully acknowledge the National Science Founda-
tion [DMR-0401780, DMR-0705015, INT-04052803], the Air
Force Office of Scientific Research (F496200-02-1-0428,03] and
the Ohio Board of Regents for financial support. Dr. Matthew
Panzner (UA) is acknowledged for his help and expertise in X-ray
structure determination.
25 G. R. Newkome, T. J. Cho, C. N. Moorefield, R. Cush,
P. S. Russo, L. A. Godınez, M. J. Saunders and P. Mohapatra,
´
Chem.–Eur. J., 2002, 8, 2946.
26 G. R. Newkome, T. J. Cho, C. N. Moorefield, P. P. Mohapatra
and L. A. Godınez, Chem.–Eur. J., 2004, 10, 1493.
´
References
27 S. H. Hwang, C. N. Moorefield, P. S. Wang, F. R. Fronczek,
B. H. Courtney and G. R. Newkome, Dalton Trans., 2006, 3518.
28 S.-H. Hwang, C. N. Moorefield, H. C. Cha, P. S. Wang and
G. R. Newkome, Des. Monomers Polym., 2006, 9, 413.
29 S.-H. Hwang, P. Wang, C. N. Moorefield, J. C. Jung, J. E. Kim,
S. W. Lee and G. R. Newkome, Macromol. Rapid Commun., 2006,
27, 1809.
30 S.-H. Hwang, C. N. Moorefield, P. S. Wang, J. Y. Kim, S. W. Lee
and G. R. Newkome, Inorg. Chim. Acta, 2007, 360, 1780.
31 S.-H. Hwang, C. N. Moorefield, L. Dai and G. R. Newkome,
Chem. Mater., 2006, 18, 4019.
1 U. S. Schubert, H. Hofmeier and G. R. Newkome, in Modern
Terpyridine Chemistry, Wiley-VCH, Weinheim, 2006.
2 V. W. W. Yam, K. M. C. Wong and N. Zhu, Angew. Chem., Int.
Ed., 2003, 42, 1400.
3 G. Ulrich and R. Ziessel, J. Org. Chem., 2004, 69, 2070.
4 P. Coppo, M. Duati, V. N. Kozhevnikov, J. W. Hofstraat and
L. De Cola, Angew. Chem., Int. Ed., 2005, 44, 1806.
5 S.-W. Lai, M. C. W. Chan, K.-K. Cheung and C.-M. Che, Inorg.
Chem., 1999, 38, 4262.
6 H.-R. Murner, E. Chassat, R. P. Thummel and J.-C. G. Bunzli,
¨
J. Chem. Soc., Dalton Trans., 2000, 2809.
¨
32 P. Wang, C. N. Moorefield, S. Li, J. Manriquez, C. D. Shreiner,
´
E. Bustos, A. L. Hartley, L. A. Godınez and G. R. Newkome,
J. Mater. Chem., 2007, 17, 3023.
33 P. S. Wang, C. N. Moorefield and G. R. Newkome, Angew. Chem.,
Int. Ed., 2005, 44, 1679.
34 F. Krohnke, Synthesis, 1976, 1.
¨
35 E. C. Constable, J. Lewis, M. C. Liptrot and P. R. Raithby, Inorg.
Chim. Acta, 1990, 178, 47.
36 R.-A. Fallahpour, M. Neuburger and M. Zehnder, Polyhedron,
1999, 18, 2445.
7 D. G. Hilmey and L. A. Paquette, J. Org. Chem., 2004, 69, 3262.
8 E. Coronado, J. R. Galan-Mascaros, C. Martı-Gastaldo,
E. Palomares, J. R. Durrant, R. Vilar, M. Gratzel and
¨
M. K. Nazeeruddin, J. Am. Chem. Soc., 2005, 127, 12351.
9 J. Hovinen and H. Hakala, Org. Lett., 2001, 3, 2473.
10 C. Galaup, J.-M. Couchet, S. Bedel, P. Tisnes and C. Picard,
J. Org. Chem., 2005, 70, 2274.
´
´
´
11 V.-M. Mukkala, H. Takalo, P. Liitti and I. Hemmila, J. Alloys
Compd., 1995, 225, 507.
¨
12 K. M. C. Wong, W.-S. Tang, B. W. K. Chu, N. Zhu and
V. W. W. Yam, Organometallics, 2004, 23, 3459.
13 Y. Sato, Y. Nakayama and H. Yasuda, J. Organomet. Chem.,
2004, 689, 744.
14 Y. Cui and C. He, Angew. Chem., Int. Ed., 2004, 43, 4210.
15 Y. Cui and C. He, J. Am. Chem. Soc., 2003, 125, 16202.
16 Y. Nakayama, Y. Baba, H. Yasuda, K. Kawakita and N. Ueyama,
Macromolecules, 2003, 36, 7953.
37 G. D. Storrier, S. B. Colbran and D. C. Craig, J. Chem. Soc.,
Dalton Trans., 1997, 3011.
38 E. C. Constable, C. E. Housecroft, M. Neuburger, D. Phillips,
P. R. Raithby, E. Schofield, E. Sparr, D. A. Tocher, M. Zehnder
and Y. Zimmermann, J. Chem. Soc., Dalton Trans., 2000, 2219.
39 I. Eryazici, C. N. Moorefield, S. Durmus and G. R. Newkome,
J. Org. Chem., 2006, 71, 1009.
40 G. D. Storrier, S. B. Colbran and D. C. Craig, J. Chem. Soc.,
Dalton Trans., 1998, 1351.
41 W. Goodall, K. Wild, K. J. Arm and J. A. G. Williams, J. Chem.
Soc., Perkin Trans. 2, 2002, 1669.
42 M. A. MacDonald, R. J. Puddephatt and G. P. A. Yap,
Organometallics, 2000, 19, 2194.
17 A. Islam, F. A. Chowdhury, Y. Chiba, R. Komiya, N. Fuke,
N. Ikeda and L. Han, Chem. Lett., 2005, 34, 344.
18 M. K. Nazeeruddin, P. Pechy, T. Renouard, S. M. Zakeeruddin,
´
R. Humphry-Baker, P. Comte, P. Liska, L. Cevey, E. Costa,
V. Shklover, L. Spiccia, G. B. Deacon, C. A. Bignozzi and
M. Gratzel, J. Am. Chem. Soc., 2001, 123, 1613.
¨
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