Coordination chemistry of some terpyridyl-polyamine bridging ligands

Article abstract of DOI:10.1071/CH09478

A series of ditopic ligands bearing terpyridyl and polyamine coordination sites have been prepared. Complexes with Ru^II bound to the terpyridyl sites of many of these ligands have been prepared. Ru^II complexes of these ligands appear vulnerable to nucleophilic displacement of the polyamine portion of the ligand by BH₄ ^-. A limited study of the coordination chemistry of the polyamine portion of the Ru^II complexes has been conducted, including the synthesis and characterization of Ru ^IICo^III heterodinuclear complexes in which the Co ^III centre is coordinated by a cyclam macrocycle. The Co ^III centre in these systems is unexpectedly labile it can be removed from the polyamine upon treatment with ethane-1,2-diamine. CSIRO 2010.

Full text of DOI:10.1071/CH09478

Full Paper
CSIRO PUBLISHING
www.publish.csiro.au/journals/ajc
Aust. J. Chem. 2010, 63, 669–679
Coordination Chemistry of Some Terpyridyl-Polyamine
Bridging Ligands∗
Ramin Zibaseresht,A,B Alan M. Downward,A and Richard M. HartshornA,C
ADepartment of Chemistry, University of Canterbury, Private Bag 4800, Christchurch, New Zealand.
BPresent address: Department of Chemistry and Physics, Maritime University of Imam Khomeini,
Nowshahr, Mazandaran, Iran.
CCorresponding author. Email: richard.hartshorn@canterbury.ac.nz
A series of ditopic ligands bearing terpyridyl and polyamine coordination sites have been prepared. Complexes with
RuII bound to the terpyridyl sites of many of these ligands have been prepared. RuII complexes of these ligands appear
vulnerable to nucleophilic displacement of the polyamine portion of the ligand by BH−4 .A limited study of the coordination
chemistry of the polyamine portion of the RuII complexes has been conducted, including the synthesis and characterization
of RuII–CoIII heterodinuclear complexes in which the CoIII centre is coordinated by a cyclam macrocycle. The CoIII centre
in these systems is unexpectedly labile – it can be removed from the polyamine upon treatment with ethane-1,2-diamine.
Manuscript received: 9 September 2009.
Manuscript accepted: 18 January 2010.
Introduction
N
Dinuclear complexes that contain a RuII polypyridyl complex
unit have attracted considerable attention because of, among
other things, their diverse electrochemical and photophysical
properties,[1–5] possible application in the conversion of solar
into electrical energy,[6–10] use in long range electron and energy
transfer,[11–15] and as photoprobes for nucleic acids such as
DNA.[16–20] The bridging ligand plays a crucial role in the
determination of the properties of these systems. Its structure
controls the spatial arrangement of the metal centres and extent
of electronic communication between them.[21,22]
N
O
N
N
N
N
N
N
N
Fig. 1. Ligand pzt.
complexes of mixed geometry and explore the photoinduced
release of ligands from the CoIII portion of the molecule.
Ligands 3, 4, and 5 were particular targets, as the numbers of
diastereoisomers that would be produced on coordination to an
octahedral CoIII ion would be limited by the relative positions
of the ligand donor atoms.
Thispaperdescribesthesynthesis, characterization, andsome
coordination chemistry of the RuII complexes of some of the
bridging ligands shown in Fig. 2. There are significant problems
withthesyntheticroutestosomeofthecomplexes, butultimately
we were able to prepare dinuclear RuII–CoIII complexes of cymt
1 that displayed unexpected lability.
Our target was to prepare RuII–CoIII systems that would allow
us to explore the possibility of achieving light-induced ligand
release. In a previous study, we demonstrated that the ditopic lig-
and, 4ꢀ-[4-{2,2,2-tris(1H-pyrazol-1-ido)ethoxymethyl}phenyl]-
2,2ꢀ:6ꢀ2ꢀ- terpyridine (pzt) (Fig. 1), bound a wide range of metal
ions at the preferred terpyridyl binding site. However, of the
metal ions we studied, only silver(i) ions coordinated strongly to
the tris(pyrazolyl)methane binding site.[23] We concluded that
we needed to provide a better binding site for the CoIII cen-
tre, and therefore turned our attention to ligands that contained
polyamine groups and macrocycles in particular. Terpyridyl
systems with the appended 1,4,8,11-tetraazacyclotetradecane,
cyclam macrocycle,[24] (cymt) 1 have already been used as
potential sensing receptors in the area of electrochemical sensor
technologies.[25–27] Padilla-Tosta et al.[25] reported that the fluo-
rescence intensity of the RuII complex was quenched selectively
in the presence of CuII in an aqueous environment at neutral pH.
It was our intention to combine derivatized terpyridyl lig-
ands with polyazamacrocycles and related groups to produce the
series shown in Fig. 2. The synthesis of such a series of ligands
would allow us to systematically develop RuII–CoIII dinuclear
Results and Discussion
Synthesis of Ligands
Many of the ligands were prepared by reaction of 4ꢀ-
(p-bromomethylphenyl)-2,2ꢀ:6ꢀ,2ꢀ-terpyridine 6 with the appro-
priate amine. These include cymt, and new ligands 4ꢀ-
{p-(1,4,7,10-tetraazacyclododec-1-ylmethyl)phenyl}-2,2ꢀ:6ꢀ,2ꢀ-
terpyridine (cynt, 2), 4ꢀ-[p-{1,5-bis(phthalimido)-3-azapentan-
3-ylmethyl}phenyl]-2,2ꢀ:6ꢀ,2ꢀ-terpyridine (bpat, 7), 4ꢀ-[p-{1,5-
bis(amino)-3-azapentan-3-ylmethyl}phenyl]-2,2ꢀ:6ꢀ,2ꢀ-terpyridine
∗This paper is dedicated to Professor Alan M. Sargeson — he will be sorely missed.
© CSIRO 2010
10.1071/CH09478
0004-9425/10/040669

670
R. Zibaseresht, A. M. Downward, and R. M. Hartshorn
N
N
N
N
N
N
HN
N
N
HN
N
HN
H
N
N
N
N
N
NHHN
NHHN
1 cymt
2 cynt
3 tcnt
N
N
N
N
N
N
N
N
Br
N
N
N
N
N
N
N
N
N
N
4 mscymt
5 mscynt
6 btp
N
O
NH2
N
N
N
N
N
N
N
N
H2N
O
N
N
N
N
O
N
O
7 bpat
8 bptt
9 dint
N
N
N
Br
N
N
N
N
HN
N
N
N
N
N
N
N
N
N
NH
N
N
O
H
10 ptmtb
11 pcymt
12 cttp
Fig. 2. Some terpyridine-based ligands discussed in this paper.
(dint, 9), 4ꢀ-[p-{(10bα,10cα)-decahydro-3a-1H,6H-3a,5a,8a,10a-
tetraazapyrenium-methyl}phenyl]-2,2ꢀ:6ꢀ,2ꢀ-terpyridine bromide
(ptmtb, 10), and 4ꢀ-[p-{(1,5,8,12-tetraazabicyclo[10.2.2]
hexadec-5-yl)methyl}phenyl]-2,2ꢀ:6ꢀ,2ꢀ-terpyridine(pcymt, 11).
Prolonged reaction times (up to 3 days) with optimized mole
ratios of the amines resulted in analytically pure products in
most cases. All products were characterized using 1H, 13C,
COSY, NOESY, and HSQC NMR spectroscopy and electrospray
ionization mass spectrometry (ESI-MS).
and collected as their PF−6 salts. Further purification of the
complexeswasachievedeitherbyusingcolumnchromatography
or by recrystallization.
Ruthenium complexes were characterized using 1H and 13
C
NMR spectroscopy, as well as ESI-MS, UV-vis spectroscopy,
and elemental analysis.
Synthesis of Ligands on Ruthenium
In the cases of cymt and cynt, the excess macrocycles were
recovered and reused. We have, however, found that the choice
of solvent is critical for avoiding di- or tri-alkylation, and can
significantly affect recovery of the excess macrocycle. Use of
toluene in the case of cymt gave the product in high yield, and
more efficient recovery of excess cyclam than when using other
solvents (CH2Cl2, CH3CN, or tetrahydrofuran (THF)). Simi-
larly, CH2Cl2 was found to be the best solvent for the synthesis
of cynt.
Insomecases, notablythepreparationofligand 19, enrouteto
mscymt 4, complexation of the terpyridine portion of the ligand
to ruthenium before completion of the ligand synthesis gave
better overall yields of the complexes. Similar comments apply
in the syntheses of 17 and 18. This is discussed later in this
paper.
In the synthesis of 17 and 18, attempts to coordinate the
polyamine-terpyridine ligands proved problematic. TLC of the
reaction mixtures suggested that many products were formed
during the reactions. This may be a result of the amine binding
sites reacting with the RuIII precursor to form different mono-
nuclearsystemsaswellasdimeric, oligomeric, andevenpossibly
polymeric systems, and possibly also oxidative dehydrogenation
reactions of the kind that has been seen in ruthenium(iii)–amine
complexes.[28,29] An alternative approach, where the terpyridine
portion of the ligand is coordinated to RuII before deprotection of
thepolyaminegroups, provedmuchmoresuccessful(Scheme1).
Coordination to RuII earlier in a synthetic route also proved
useful in the context of the bridged cyclam-based ligand 4. The
synthesis of free mscymt 4 was attempted by reacting ptmtb
10 with iodomethane, however, a suitable solvent could not
be found because of the mismatch of reagent solubilities. For
this reason ptmtb 10 was complexed with [Ru(tpy)Cl3] and the
resulting complex 20 precipitated as the PF−6 salt. Alkylation
with iodomethane then smoothly gave complex 21 in CH3CN
(Scheme 2).
Synthesis of Complexes
RuII complexes 13–16 (Fig. 3), which contain bpat, cynt, cymt,
and ptmtb, respectively, were synthesized by reaction of the
ruthenium precursor [Ru(ttp)Cl3] with the corresponding lig-
ands in boiling MeOH. Crude products could be precipitated
Unfortunately, borohydride reduction of 21 resulted in the
isolation of [Ru(ttp)2](PF6)2 (23) instead of the desired product.

Terpyridyl-Polyamine Bridging Ligands
671
N
N
N
N
N
N
Ru
N
(PF6)3
N
Ru
N
N
(PF6)2
N
N
N
N
HN
N
N
NH HN
13
14
N
N
N
N
N
N
Ru
N
Ru
N
N
(PF6)2
(PF6)2
N
N
N
N
N
HN
N
N
N
NH HN
15
16
Fig. 3. Ru(ii) complexes of bpat (13), cynt (14), cymt (15), and ptmb (16).
N
Cl
N
Ru Cl
Cl
N
(iii)
(i)
2ϩ
3ϩ
N
N
O
N
N
N
N
Ru
N
N
N
N
Ru
N
N
H2N
N
N
O
N
O
N
N
O
O
(iv)
(ii)
2ϩ
2ϩ
N
N
N
N
N
N
Ru
N
N
Ru
N
NH2
N
HN
N
H
N
N
N
N
H2N
18
17
Scheme 1. (i) bptt, N-methylmorpholine, MeOH, reflux 2 h. (ii) Ethane-1,2-diamine, MeOH, room temperature, overnight. (iii) cttp,
N-methylmorpholine, MeOH, reflux, overnight. (iv) KOH, EtOH/water (3/1), reflux, 3 days.

672
R. Zibaseresht, A. M. Downward, and R. M. Hartshorn
Ϫ
N
N
N
N
Br
Br
N
N
(iv)
(v)
ϩ
N
N
N
N
N
N
N
N
N
N
ϩ
N
N
N
ϩ
N
N
Ϫ
10
19
4
I
(i)
N
3ϩ
4ϩ
N
N
N
N
N
N
Ru
N
N
Ru
N
(ii)
N
N
N
N
N
N
N
N
N
N
21
20
(iii)
(v)
2ϩ
2ϩ
N
N
N
N
N
Ru
N
N
Ru
N
N
N
N
N
N
N
N
N
23
22
Scheme 2. Ligand synthesis on ruthenium (dotted arrows indicate reactions that were not achieved). (i) Ru(ttp)Cl3, MeOH. (ii) MeI, CH3CN.
(iii) NaBH4, EtOH. (iv) MeI. (v) NaBH4.
In principle, this could be the result of ligand exchange reactions
and/or nucleophilic displacement of the polyamine groups from
either 21 or 22. The high yields from these reactions together
with the relatively inert nature of RuII complexes led us to infer
that the primary route for formation of the [Ru(ttp)2]2+ ion is
likelythroughnucleophilicdisplacementoftheaminebyhydride
rather than ligand exchange.
In order to further investigate whether ligand exchange could
be a source of the ttp ligand in this kind of reaction, [Ru{2,4-
di(pyridin-2-yl)-6-p-tolyl-1,3,5-triazine}(pzt)](PF6)2 wastreated
with borohydride. [Ru{2,4-di(pyridin-2-yl)-6-p-tolyl-1,3,5-
triazine}(ttp)](PF6)2 was isolated, which led us to conclude that
Ru–terpyridine derivatives of this kind are unstable towards
borohydride reagents. This means that the synthetic routes to Ru
complexes of the cross-bridged macrocycles, 4 and 5, become
very problematic. A second alkylation of the cyclam–bisaminal
derivative is required before reduction (as otherwise reduction
gives the piperazine derivatives such as 11 rather then the cross-
bridged cyclam),[30] but the alkylation reactions must be done
on the complex (because of solubility problems), and the ligand
will not survive the borohydride reduction conditions when still
coordinated to the metal.
15 with Na3[Co(NO2)6]. The product was isolated in good
yield as its PF−6 salt and characterized using H, 13C, COSY,
1
NOESY, and HSQC NMR techniques, as well as ESI-MS, UV-
vis spectroscopy, and elemental analysis. Efforts to produce
X-ray quality crystals of this complex proved unsuccessful.
Treating the dinitrito complex with 6 M HCl gave a dichlorido
complex that was characterized using 1H and 13C NMR, UV-vis
spectroscopy, and ESI-MS techniques.
Unfortunately, attempts to identify which isomers of
the dinitrito and dichlorido complexes were formed proved
unsuccessful. The UV-vis spectra of [Ru(ttp)(cymt)](PF6)2,
[(ttp)Ru(cymt)Co(NO2)2](PF6)3, and [(ttp)Ru(cymt)Co(Cl)2]
Cl3 were all very similar in appearance, with the dominant peak
at 490 nm being the metal-to-ligand charge transfer (MLCT)
transition characteristic of the RuII–polypyridyl systems. The
presence of these large MLCT bands obscured the CoIII d–d
bands. The shape and location of the d–d bands could not, there-
fore, be used to determine which of the cis or trans isomers were
formed.
Literature reports suggest that trans isomers of CoIII com-
plexes of cyclam and two monodentate ligands are the dominant
products in aqueous solution,[31,32] while Poon and Tobe have
reported that cis complexes with monodentate ligands eventu-
ally isomerize to a trans configuration in aqueous solution.[33]
This leads us to speculate that the product complexes are most
likely trans isomers.
Heterodinuclear RuII–CoIII Complexes
The heterodinuclear complex [(ttp)Ru(cymt)Co(NO2)2](PF6)3,
24 (Scheme 3), was prepared by reacting the RuII complex

Terpyridyl-Polyamine Bridging Ligands
673
N
N
N
N
Ru
N
3[PF6]
NO2
NH
NH
N
N
Co
NO2
HN
24
Scheme 3.
Reaction of the dichlorido complex with excess ethane-1,2-
diamine resulted in removal of the cobalt from the macrocycle
and reisolation of the parent complex 15. This was a disappoint-
ing result in that the ethane-1,2-diamine complex would have
been very useful to monitor light-induced ligand release using
NMR methods, but also rather remarkable in that CoIII–cyclam
complexes would generally be regarded as rather inert. Use of
less ethane-1,2-diamine and milder reaction conditions resulted
in either no reaction or loss of smaller amounts of CoIII from the
macrocycle.
This result led to the attempt to prepare the related bridged
cyclam complexes, as we anticipated that using ligands that
forced a cis configuration at cobalt may allow milder ligand
substitution reaction conditions to be employed. Unfortunately,
synthetic difficulties (outlined above) precluded this approach,
and other polyamines were tried.
During attempted reactions of the Ru–terpyridine–tacn com-
plex 18 with [Co(tacn)Cl3] in aqueous solutions, the cobalt
complex reacted with itself to produce oxido-bridged dicobalt
complexes rather than heterodinuclear RuII–CoIII species (one
suchdicobaltproductwasidentifiedfromapoorsinglecrystalX-
ray diffraction study). However, solid materials could be isolated
following reaction of 18 with Na3[Co(NO2)6], [Co(dien)Cl3], or
[Co(dien)(H2O)3]. ESI-MS results that were obtained on these
samples are consistent with successful coordination of CoIII.
Evidence for coordination of NiII or AgI was also seen using
ESI-MS, but not with other metal ions (CuII, FeII, ZnII, and
CdII).
unexpectedly labile. Further study of the heterobimetallic com-
plexes is no doubt warranted, but the RuII–CoIII systems have
proven unsuitable for study of photo-induced ligand release, and
we have, therefore, moved on to a different series of bridging
ligands for the synthesis of such systems.
Experimental
General Experimental
Allsolventsusedinthesynthesesweredriedanddistilledaccord-
ing to the standard methods[34] before use.All dried and distilled
solvents used in reactions of air-sensitive compounds were de-
aerated before use by saturation with argon. Syntheses of ligands
and their complexes were carried out under an inert atmosphere
of argon using standard Schlenk techniques.
1H and 13C NMR spectra were recorded on Varian UNITY-
300 or Varian INOVA-500 spectrometers. 1H and 13C NMR
chemical shifts are referenced to residual solvent resonances
1
or using TMS as an internal reference. H NMR spectra were
assigned using two-dimensional COSY and NOESY techniques.
NMR assignments of 1H and 13C atoms that do not form part of
terpyridine portions of molecules have locants of the form Ox
(e.g. 01, 04). Infrared spectra (400–4000 cm−1) were obtained
using a Shimadzu 8201PC Series FTIR interfaced with an Intel
486 PC operating Shimadzu HyperIR software. Spectra were
obtained using a diffuse reflectance method in solid KBr. Micro-
analyses were performed at the University of Otago. Solutions
(10 µg mL−1) for ESI-MS were recorded using milliQ water
or reagent grade dimethyl sulfoxide (DMSO) and MeOH in
a Micromass LCT Waters 2795 Mass Spectrometer. UV-vis
spectra were recorded on a Varian CARY Probe 50 UV-vis
Spectrophotometer.
The coordination of AgI to the amine site of 17 (on addition
of AgClO4) could be observed using both ESI-MS (Fig. 4) and
1H NMR spectroscopy. While the chemical shifts of the proton
signals in the aromatic region remained largely unchanged, those
in the amine region showed significant change. Similar results
were seen with AgBF4.
The ligands 4ꢀ-(p-tolyl)-2,2ꢀ:6ꢀ,2ꢀ-terpyridine (ttp),[35–37] 4ꢀ-
(p-bromomethylphenyl)-2,2ꢀ:6ꢀ,2ꢀ-terpyridine(btp, 6),[36,37] 1,5-
bis(phthalimido)-3-azapentane,[38] N,Nꢀ-bis(2-pyridylmethyl)
amine,[39] 1,4,8,11-tetraazacyclotetradecane (cyclam),[24] cis-
decahydro-1H,6H-3a,5a,8a,10a-tetraazapyrene[40] (bisaminal-
cyclam), 1,4,7,10-tetraazacyclododecane (cyclen),[41,42] 1,4,7-
triazacyclononane (tacn),[41,42] 1,4,7-triazatricyclodecane
Conclusion
Several new RuII complexes have been prepared that carry
polyamine binding sites. In some cases the terpyridine–
polyamine ligand was prepared and then bound to ruthenium,
while in other cases coordination of the ruthenium ion must be
achieved before synthesis of the amine portion of the ligand
is completed. We have established that substituted terpyridine
ligands of the kind that we have prepared are vulnerable to reac-
tion with borohydride when they are bound to RuII. Once RuII
complexes of terpyridine–polyamine ligands are prepared it is
possible to demonstrate the binding of some transition metal ions
in the polyamine site. While RuII–CoIII systems of the kind we
were seeking to study could be prepared, they were found to be
(capped-tacn),[43]
and
4ꢀ-(p-(1,4,7-triazacyclonon-1-yl)
methylphenyl)-2,2ꢀ:6ꢀ,2ꢀꢀ-terpyridine, 3,[44] were prepared by
following literature methods. Benzoyl peroxide (BPO) and N-
bromosuccinimide (NBS) were purchased from Aldrich and
recrystallized using standard methods and dried over P2O5 and
under vacuum before use.
Complexes[Ru(ttp)Cl3],[45] [Co(tacn)(Cl)3], [Co(dien)(Cl)3],
[Co(trien)(Cl)2], [Co(tren)(Cl)2], and [Co(NH3)5(OH2)] were
synthesized according to the literature methods. All other start-
ing materials were obtained commercially and used without
further purification.

674
R. Zibaseresht, A. M. Downward, and R. M. Hartshorn
(a)
(b)
(c)
RZ 210
RZ 210
RZ 210
RAZ0193 (0.019) Cu (0.01); Is (1.00,1.00) C
H
N
RuNiClO PF
RAZ0193 (0.019) Cu (0.01); Is (1.00,1.00) C
H
N
RuNiClO ClO
4
RAZ0193 49 (0.820) Cm (21:103)
48 45
9
4
6
48 45
9
4
TOF MS ESϩ
1.72e12
TOF MS ESϩ
656
TOF MS ESϩ
1.73e12
577.5750
576.5750
554.5671
350.7336
100
100
100
351.0659
351.3897
553.5671
554.0671
350.3839
577.0750
576.0750
555.5671
351.7311
350.0693
578.0750
578.5750
553.0671
%
%
%
352.0640
349.7199
575.5750
552.5671
552.0671
556.0671
352.3970
352.4496
575.0750
556.5671
349.4056
349.0653
579.0750
579.5750
580.0750
mass
551.5671
550.5671
557.0671
574.5750
573.5750
353.0722
0
m/z
mass
0
0
349
350
351
352
353
551
552
553
554
555
556
557
573
574
575
576
577
578
579
580
(a) RZ 210
RAZ0193 (0.019) Is (1.00,1.00) C
(b) RZ 210
RAZ0193 (0.019) Is (1.00,1.00) C
(c) RZ 210
H
N
RuNiClO PF
4
H
N
RuNiClO ClO
4
RAZ0193 (0.019) Is (1.00,1.00) C
H
N RuNiPF
48 45
9
6
48 45
9
4
48 45 9 6
577.5731
351.7354
554.5650
576.5736
100
100
100
TOF MS ESϩ
TOF MS ESϩ
TOF MS ESϩ
1.73e12
1.72e12
2.00e12
553.5656
352.4018
577.0738
554.0657
555.5643
352.0690
351.4023
576.0739
553.0660
578.0737
578.5725
%
%
%
352.7357
351.0690
575.5740
552.5660
552.0666
556.0649
556.5637
353.0682
350.7358
575.0743
579.0731
579.5720
551.5660
550.5671
353.4018
353.7346
557.0641
349.7362
350.4023
350.0706
574.5740
580.0723
mass
0
mass
0
mass
580
0
550 551 552 553 554 555 556 557
350
351
352
353
354
574
575
576
577
578
579
RZ 211
RZ 239-1
RZ 239-1
(d)
(e)
(f)
RAZ0192 (0.017) Cu (0.01); Is (1.00,1.00) C
H
N
RuAgClO
4
RAZ0239 196 (3.270) Cm (123:270)
RAZ0239 196 (3.270) Cm (123:270)
48 45
9
TOF MS ESϩ
1.88e12
TOF MS ESϩ
628
TOF MS ESϩ
317
529.5778
1191.2150
1191.1827
523.1514
100
100
100
528.5778
529.0778
1190.2487
522.6603
522.1481
521.6470
524.1554
1193.2938
1190.1680
1192.2461
1193.3583
530.5778
1190.1357
1189.2344
523.6533
528.0778
%
%
%
520.1555
520.6559
1188.2849
1188.1722
1188.1400
524.6578
1193.4872
1194.2936
527.5778
527.0778
521.1674
525.3423
531.0778
1194.4873
1194.5840
1185.2622
1187.1429
1195.4067
531.5778
526.5778
525.5778
m/z
1196
0
m/z
0
mass
0
1186
1188
1190
1192
1194
520
521
522
523
524
525
525 526 527 528 529 530 531 532
RZ 211
RAZ0192 (0.017) Is (1.00,1.00) C
RZ 239-1
RAZ0239 (0.017) Is (1.00,1.00) C
RZ 239-1
H
N
RuAgClO
H
N
RuCoN
O
RAZ0239 (0.017) Cu (0.01); Is (1.00,1.00) C
H
N RuCoN O PF
48 45
9
4
48 45
9
3
6
48 45 9 3 6 6
TOF MS ESϩ
1.88e12
TOF MS ESϩ
2.44e12
TOF MS ESϩ
2.44e12
524.1060
1191.1635
529.5765
100
100
100
528.5767
529.0771
1190.1635
1193.1635
523.6064
525.1065
524.6071
530.5766
528.0770
1192.1635
1189.1635
%
%
%
523.1061
1188.1635
522.6063
527.5770
527.0775
1194.1635
525.6075
531.0776
531.5770
1185.1635
1186.1635
526.5775
525.5778
521.1069
521.6084
1195.1713
mass
526.1088
0
mass
0
mass
0
1186
1188
1190
1192
1194
1196
525
526
527
528
529
530
531
532
521
522
523
524
525
526
Fig. 4. Selected ESI-MS signals from (a) [(ttp)Ru(dint)Ni(ClO4)(PF6)]2+, (b) [(ttp)Ru(dint)Ni(ClO4)2]2+, (c) [(ttp)Ru(dint)Ni(PF6)]3+
,
(d) [(ttp)Ru(dint)Ag(ClO4)]2+, (e) [(ttp)Ru(dint)Co(NO2)3(PF6)]+, and (f) [(ttp)Ru(dint)Co(NO2)3]2+, at m/z 577.5750, 554.5671, 351.0659,
529.5778, 523.1514, and 1191.2150, respectively. (A) High resolution scans. (B) Calculated isotopic distribution patterns.

Terpyridyl-Polyamine Bridging Ligands
675
CAUTION! Perchlorate salts of metal complexes containing
organic ligands are potentially explosive and should be handled
with care and in small quantities.
4ꢀ-[p-{1,5-Bis(amino)-3-azapentan-3-ylmethyl}phenyl]-
2,2ꢀ:6ꢀ,2ꢀ-terpyridine (dint, 9)
Compound 8 (0.5 g, 0.73 mmol) in CH2Cl2 (25 mL) was
added into a MeOH solution of ethane-1,2-diamine (0.5 M,
25 mL), and the mixture was stirred for 48 h at room tem-
perature, filtered, and the filtrate was concentrated to dryness
to give a yellow oil. The mixture was dissolved in CHCl3
(50 mL). The CHCl3 solution was washed with 3% NH4OH
solution (3 × 50 mL), and the organic layer was dried over
MgSO4, filtered, and the filtrate was concentrated to dryness
to give a yellow non-solid material in a quantitative yield. δH
Syntheses of Ligands
4ꢀ-[p-{N,N-Bis(2-pyridylmethyl)aminomethyl}phenyl]-
2,2ꢀ:6ꢀ,2ꢀ-terpyridine (bpat, 7)
A mixture of N,Nꢀ-bis(2-pyridylmethyl)amine[39] (0.24 g,
1.2 mmol) and 6 (0.4 g, 1.0 mmol), and anhydrous K2CO3 (1.4 g,
10 mol) in dry CH3CN (50 mL) was stirred at 55–60◦C under
argon for 3 days. The progress of the reaction was monitored by
TLC.The reaction mixture was then allowed to cool to room tem-
perature, filtered, and the solvent was removed from the filtrate
under reduced pressure to give a pale yellow oil. Purification
by column chromatography (Al2O3, 1–2% MeOH in CH2Cl2)
afforded the desired product (0.52 g, 96%) as a pale yellow oil.
ꢀ
ꢀ
(500 MHz, CDCl3) 8.725 (2H, s, H3 , H5 ), 8.72 (2H, d, H6,
ꢀ
ꢀ
ꢀ
ꢀꢀ
H6 ), 8.67 (2H, d, H3, H3 ), 7.88–7.83 (4H, m, H4, H4 , H2 ,
ꢀꢀ
ꢀ
ꢀꢀ
ꢀꢀ
H6 ), 7.69 (2H, m, H06, H06 ), 7.44 (2H, d, H3 , H5 ), 7.34
ꢀ
ꢀ
(2H, m, H5, H5 ), 3.66 (2H, s, H7), 2.79 (4H, m, H02, H02 ),
ꢀ
2.56 (4H, m, H01, H01 ), 1.92 (4H, b, NH2). δC (75 MHz,
CDCl3) 156.17 (2C), 155.84 (2C), 149.94, 149.06 (2C, C6,
ꢀ
ꢀ
ꢀꢀ
C6 ), 140.55, 137.19, 136.81 (2C, C4, C4 ), 129.35 (2C, C3 ,
ꢀ
ꢀ
ꢀꢀ
ꢀꢀ
ꢀꢀ
ꢀ
δH (500 MHz, CDCl3) 8.729 (2H, s, H3 , H5 ), 8.725 (2H, d, H6,
C5 ), 127.23 (2C, C2 , C6 ), 123.76 (2C, C5, C5 ), 121.29
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
H6 ), 8.67 (2H, d, H3, H3 ), 8.54 (2H, d, H04, H04 ), 7.87 (2H,
(2C, C3, C3 ), 118.73 (2C, C3 , C5 ), 58.92 (C7), 57.08 (2C,
C01, C01 ), 39.66 (2C, C02, C02 ). νmax (KBr)/cm−1 2802brs,
1653m, 1585s, 1568m, 1541m, 1516m, 1470shs, 1443w, 1418w,
1391m, 1315w, 1265w, 1115brs, 1040w, 1016w, 991w, 895m,
831w, 791shs, 741m, 719w, 687m, 617m, 579w, 525w, 509w,
486w, 469w, 459w, 440w, 419m. m/z (ESI) 213.1583 (100%,
[M + 2H]2+), 425.3123 (9, [M + H]+).
ꢀ
ꢀꢀ
ꢀꢀ
ꢀ
ꢀ
ꢀ
m, H4, H4 ), 7.86 (2H, d, H2 , H6 ), 7.69 (2H, m, H06, H06 ),
7.61 (2H, d, H07, H07 ), 7.56 (2H, d, H3 , H5 ), 7.35 (2H, m, H5,
ꢀ
ꢀꢀ
ꢀꢀ
ꢀ
ꢀ
ꢀ
H5 ), 7.17 (2H, m, H05, H05 ), 3.86 (4H, s, H01, H01 ), 3.77 (2H,
s, H7). δC (75 MHz, CDCl3) 159.61, 156.24, 155.87, 150.03,
149.09 (2C, C6, C6 ), 148.98 (2C, C04, C04 ), 140.18, 137.23,
136.83 (2C, C4, C4 or C2 , C6 ), 136.46 (2C, C06, C06 ), 129.35
(2C, C3 , C5 ), 127.26 (2C, C4, C4 or C2 , C6 ), 123.78 (2C,
ꢀ
ꢀ
ꢀ
ꢀꢀ
ꢀꢀ
ꢀ
ꢀꢀ
ꢀꢀ
ꢀ
ꢀꢀ
ꢀꢀ
4ꢀ-[p-{(10bα,10cα)-Decahydro-1H,6H-3a,5a,8a,10a-
tetraazapyrenium-3a-methyl}phenyl]-2,2ꢀ:6ꢀ,2ꢀ-
terpyridine bromide (ptmtb, 10)
ꢀ
ꢀ
ꢀ
C5, C5 ), 122.85 (2C, C07, C07 ), 122.00 (2C, C05, C05 ), 121.31
ꢀ
ꢀ
ꢀ
ꢀ
(2C, C3, C3 ), 118.74 (2C, C3 , C5 ), 60.06 (2C, C01, C01 ), 58.20
(C7). m/z (ESI) 261.1370 (100%, [M + 2H]2+), 521.2880 (14,
[M + H]+).
A solution of (10bα,10cα)-decahydro-1H,6H-3a,5a,8a,10a-
tetraazapyrene (bisaminal–cyclam) (0.222 g, 1.0 mmol) and 6
(0.40 g, 1.0 mmol) in dry THF (35 mL) was stirred at room tem-
perature for 4 days. The resulting white precipitate was filtered
off, washed with diethyl ether, and air-dried to afford an ana-
lytically pure powder. The volume of the filtrate was reduced to
approximately 10 mL. The precipitate was separated by filtra-
tion, and washed with diethyl ether to obtain the second crop.
4ꢀ-[p-{1,5-Bis(phthalimido)-3-azapentan-3-
ylmethyl}phenyl]-2,2ꢀ:6ꢀ,2ꢀ-terpyridine (bptt, 8)
A mixture of 1,5-bis(phthalimido)-3-azapentane[38] (0.43 g,
1.2 mmol), 6 (0.4 g, 1.0 mmol), and anhydrous K2CO3 (1.4 g,
10 mmol) in dry CH3CN (50 mL) was stirred at 55–60◦C under
argon for 3 days. The progress of the reaction was monitored by
TLC.The reaction mixture was then allowed to cool at room tem-
perature, filtered, and the solvent was removed from the filtrate
under reduced pressure to give a pale yellow oil. Water (100 mL)
was added to the crude product and was then extracted with
CH3Cl (3 × 100 mL). After drying over MgSO4, it was filtered,
and the solvent was removed from the filtrate to afford the analyt-
ically pure desired product (0.67 g, 98%) as a non-solid material.
ꢀ
Yield (total) 11%. δH (500 MHz, D2O) 7.87 (2H, d, H6, H6 ),
ꢀ
ꢀ
7.28 (2H, d, H3, H3 ), 7.25–7.22 (2H, m, H4, H4 ), 7.00 (2H,
ꢀ
ꢀ
ꢀ
ꢀꢀ
s, H3 , H5 ), 6.94–6.92 (2H, m, H5, H5 ), 6.87 (2H, d, H3 ,
ꢀꢀ
ꢀꢀ
ꢀꢀ
H5 ), 6.79 (2H, d, H2 , H6 ), 4.69–4.66 and 4.19–4.16 (AB,
2H, H7A, H7B), 4.05 (1H, br s, H015), 3.88–3.67 (1H, H02(ax)),
3.50 (1H, brs, H016), 3.36–3.34 (1H), 3.23 (1H, H014(ax)), 2.94–
2.88 (6H, including H03(eq), H05(ax), H012(eq)), 2.76–2.74 (2H,
including H014(eq)), 2.53–2.50 (2H, H02(eq), H03(ax)), 2.37–2.35
(2H, including H05(eq)), 2.15–2.13 (2H, H012(ax), H06(eq)), 1.95–
1.93 (1H, H013(eq)), 1.60–1.58 (1H, H013(ax)), 1.37–1.35 (1H,
H06(ax)). δC (75 MHz, D2O) 153.71, 153.30, 147.90 (2C, C6,
ꢀ
δH (500 MHz, CDCl3) 8.77 (2H, d, H6, H6 ), 8.68 (2H, d, H3,
H3 ), 8.60 (2H, s, H3 , H5 ), 7.90–7.86 (4H, m, H4, H4 ), 7.74–
7.69 (8H, m, H06–09, H06 –09 ), 7.39 (2H, d, H2 , H6 ), 7.36 (2H,
m, H5, H5 ), 7.17 (2H, d, H3 , H5 ), 3.79 (4H, m, H02, H02 ), 3.69
(2H, s, H7), 2.84 (4H, m, H01, H01 ). δC (75 MHz, CDCl3) 168.20
(4C, C04), 156.27, 155.72, 149.76, 149.06 (2C, C6, C6 ), 140.12,
136.81 (2C, C4, C4 ), 136.59, 133.71 (4C, aromatic phthalim-
ide), 132.31 (4C), 129.57 (2C, C3 , C5 ), 126.76 (2C, C2 , C6 ),
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
ꢀꢀ
ꢀꢀ
ꢀ
ꢀꢀ
ꢀꢀ
C6 ), 146.26, 137.79, 137.54, 133.21 (2C, C3 , C5 ), 126.47,
ꢀ
ꢀꢀ
ꢀꢀ
ꢀ
ꢀꢀ
ꢀꢀ
ꢀ
125.93 (2C, C2 , C6 ), 124.29, 121.44 (2C, C3, C3 ), 116.72 (2C,
ꢀ
ꢀ
ꢀ
C3 , C5 ), 82.62 (C016), 69.50 (C015), 61.39 (C7), 59.84 (C014),
53.98 (C03), 53.29 (C05), 51.91 (C012), 51.35, 47.86 (C02), 46.52,
41.90, 18.40 (C013), 17.95 (C06). m/z (ESI) 272.6939 (100%,
[M + H − Br]2+), 544.3924 (10, [M − Br]+).
ꢀ
ꢀ
ꢀꢀ
ꢀꢀ
ꢀꢀ
ꢀꢀ
ꢀ
123.77 (2C, C5, C5 ), 123.00 (4C, aromatic phthalimide), 121.27
(2C, C3, C3 ), 118.64 (2C, C3 , C5 ), 57.76 (C7), 51.91 (2C, C01,
ꢀ
ꢀ
ꢀ
4ꢀ-[p-{(10bα,10cα)-Decahydro-1H,6H-3a,5a,8a,10a-
tetraazapyrenium-3a-methyl}phenyl]-2,2ꢀ:6ꢀ,2ꢀ-
terpyridine (pcymt, 11)
C01 ), 35.71 (2C, C02, C02 ). νmax (KBr)/cm−1 3051w, 3016w,
2943w, 2822m, 1773s, 1711ssh, 1603m, 1583s, 1568m, 1542m,
1514w, 1468m, 1431m, 1396ssh, 1327m, 1265w, 1190w, 1170w,
1159w, 1086s, 1038m, 1018w, 991w, 966w, 895w, 872w, 831w,
791s, 746m, 719ssh, 687w, 660m, 621m, 530m, 478w, 469w,
415w. m/z (ESI) 684.9885 (100%, [M + H]+).
ꢀ
ꢀ
A modified method was adopted for the ring cleavage reduc-
tion of ptmtb, 10.[30] To a stirred solution of 10 (0.5 g) in 95%
EtOH (40 mL) was added excess NaBH4 in small portions over

676
R. Zibaseresht, A. M. Downward, and R. M. Hartshorn
1 h. The reaction mixture was stirred at room temperature for
16 days. Excess NaBH4 was then decomposed by slow addition
of 3 M HCl at 0◦C, and the solvent was removed under vacuum.
The resulting white solid was dissolved in water, the pH was
adjusted to 14 (by adding a concentrated solution of KOH with
cooling), and the basic solution was extracted with benzene, and
then CH2Cl2. The combined extracts were dried using MgSO4,
filtered, and the solvent was removed to afford a white solid.
7.47 (2H, d), 7.37–7.35 (2H, m), 3.70 (2H, s, H01), 2.85–2.62
(16H, m). δC (75 MHz, CDCl3) 156.20, 155.79, 149.88, 149.04
(2C), 140.11, 137.07, 136.77 (2C), 129.57 (2C), 127.22 (2C),
123.70 (2C), 121.27 (2C), 118.68 (2C), 58.79, 51.22, 46.94,
46.16, 29.62. m/z (ESI) 494.2987 (100%, [M + H]+).
Syntheses of Complexes
[(ttp)Ru(bptt)](NO3)2
ꢀ
ꢀ
Yield 85%. δH (500 MHz, CDCl3) 8.65 (2H, s, H3 , H5 ), 8.62
[Ru(ttp)Cl3] (0.187 g, 0.353 mmol) was added to the ligand
bptt, 8 (0.242 g, 0.353 mmol), in dry MeOH (20 mL) under an
Ar atmosphere. Ten drops of N-methylmorpholine was added.
The solution was heated to reflux with stirring for 2 h, and then
cooled to room temperature.The resulting deep-red solution was
filtered through Celite to remove any unreacted [Ru(ttp)Cl3]
and excess methanolic solution of ammonium hexafluorophos-
phate was added to the filtrate to precipitate the complexes.
Further purification was achieved by column chromatography
over silica eluting with CH3CN/saturated KNO3 solution/H2O
(7/0.5/1). The major orange-red band was collected. The NO3−
salt of this complex was used in the subsequent reaction. δH
ꢀꢀ
ꢀꢀ
(2H, d), 8.59 (2H, d), 7.80–7.78 (4H, m, including H2 , H6 ),
ꢀꢀ
ꢀꢀ
7.32 (2H, d, H3 , H5 ), 7.28 (2H, m), 3.59 (2H, s, H7), 3.26–3.24
(2H, m, H010 or H015), 3.08 (2H, m, H010 or H015), 2.80–2.76
(2H, t, H012), 2.69 (4H, br, H02 or H05), 2.60 (2H, H07), 2.54
(4H, m, H03 or H014), 2.48–2.44 (2H, m, H09 or H016), 2.26
(2H, m, H09 or H016), 1.88 (2H, m, H06), 1.67 (2H, m, H013).
δC (75 MHz, CDCl3) 155.96, 149.49, 148.99, 138.79, 137.60,
ꢀꢀ
ꢀꢀ
ꢀꢀ
ꢀꢀ
136.88 (2C, C2 , C6 ), 129.81 (2C, C3 , C5 ), 128.20, 127.24,
ꢀ
ꢀ
123.56, 121.31, 118.58 (2C, C3 , C5 ), 57.59 (C7), 56.09 (C07),
55.59 (C012), 53.55 (C02), 50.63 (2C, C09, C016), 50.14 (C05),
48.69 (2C, C010, C015), 47.14 (C03), 23.39 (C06), 23.13 (C013).
4ꢀ-{p-(1,4,8,11-Tetraazacyclotetradec-1-
(500 MHz, (D6)DMSO) 9.58 (2H, s, H3 (bptt), H5 (bptt)), 9.49
ꢀ
ꢀ
ylmethyl)phenyl}-2,2ꢀ:6ꢀ,2ꢀ-terpyridine (cymt, 1)
(2H, s, H3 (ttp), H5 (ttp)), 9.23 (4H, d, H3(bptt, ttp)), H3 (bptt,
ꢀ
ꢀ
ꢀ
ꢀꢀ
ꢀꢀ
ꢀꢀ
ttp)), 8.49 (2H, d, H2 (ttp), H6 (ttp)), 8.26 (2H, d, H2 (bptt),
A solution of 6 (0.40 g, 1.0 mmol), in dry toluene (20 mL)
under Ar was added dropwise to a stirred mixture of cyclam[24]
(1.0 g, 5 mmol) and anhydrous K2CO3 (3.5 g, 25 mmol) in dry
toluene at 30◦C over a period of 2 h. The reaction mixture was
stirred at 100◦C overnight, cooled to room temperature, filtered
to remove K2CO3 and excess cyclam (the excess cyclam was
then recovered from the filtered material by washing the solid
thoroughly with CHCl3, and removing the solvent on a rotary
evaporator). Toluene was removed from the filtrate under vac-
uum to afford a pale oil, which was solidified on scratching.
The crude material was purified by column chromatography
(Al2O3, eluting with CH2Cl2 and then with 2–3% MeOH in
CH2Cl2) to afford a glassy off-white solid. Yield 0.277 g, 53%.
ꢀꢀ
ꢀ
H6 (bptt)), 8.20–8.15 (4H, m, H4(bptt, ttp), H4 (bptt, ttp)), 7.94–
7.92 (4H, m, aromatic, phthalimide), 7.85–7.83 (4H, m, aro-
ꢀ
matic, phthalimide), 7.69–7.65 (6H, m, H6(bptt, ttp), H6 (bptt,
ꢀꢀ
ꢀꢀ
ꢀꢀ
ꢀꢀ
ttp), H3 (ttp), H5 (ttp)), 7.58 (2H, d, H3 (bptt), H5 (bptt)), 7.41–
ꢀ
7.38 (4H, m, H5(bptt, ttp), H5 (bptt, ttp)), 3.92 (2H, s, H7),
ꢀ
ꢀ
3.82 (4H, m, H02, H02 ), 2.90 (4H, m, H01, H01 ), 2.62 (3H, s,
CH3). δC (75 MHz, (D6)DMSO)206.71, 167.96, 158.21, 155.17,
152.33, 146.99, 146.60, 141.67, 140.46, 138.17, 134.38, 133.26,
131.85, 130.14, 129.56, 127.86, 127.67, 127.27, 124.97, 122.98,
120.82, 56.96, 51.59, 35.50, 21.11. m/z (ESI) 1171.5535 (1%,
[M − (NO3)]+), 554.8108 (58, [M − 2(NO3)]2+), 370.2076
(100, [M + H − 2(NO3)]3+). λmax/nm (ε/L mol−1 cm−1) 229.9
(37263), 240.0 (40974), 250 (41554), 265.1 (42072), 500.0
(3761). To obtain the yield of the reaction, the complex was iso-
lated as its PF−6 salt as a red powder.Yield 0.39 g, 80%.The same
sample was submitted for elemental analysis. (Found: C 53.14,
H 3.52, N 8.62. Anal. Calc. for C64H49F12N9O4P2Ru·3H2O
(1453.18): C 52.90, H 3.81, N 8.67%.)
ꢀ
δH (500 MHz, CDCl3) 8.74–8.72 (2H, d), 8.735 (2H, s, H5 ,
ꢀ
ꢀꢀꢀ
ꢀꢀꢀ
H3 ), 8.68 (2H, d), 7.90–7.87 (4H, m), 7.50 (2H, d, H5 , H3 ),
7.37–7.35 (2H, m), 3.65 (2H, s, H7), 2.88 (2H, m), 2.84 (2H,
m), 2.77–2.72 (4H, m), 2.68–2.59 (4H, m), 2.57 (2H, m), 2.56
(2H, m), 1.90–1.88 (2H, m, H013), 1.73–1.71 (2H, m, H06). δC
(75 MHz, CDCl3) 156.31, 155.91, 150.06, 149.12 (2C), 140.06,
137.11, 136.87 (2C), 129.70 (2C), 127.13 (2C), 123.80 (2C),
121.39 (2C), 118.74 (2C), 57.73, 54.47, 53.39, 50.74, 49.32,
49.14, 49.00, 47.91, 47.43, 28.40, 26.18. m/z (ESI) 522.3300
(100%, [M + H]+).
[(ttp)Ru(dint)](PF6)3 (17)
[(ttp)Ru(bptt)](NO3)2 (0.12 g, 0.1 mmol) in MeOH (10 mL)
was added into a MeOH solution of NH2NH2 (0.5 M, 10 mL),
and the mixture was stirred overnight at room temperature, fil-
tered, and excess aqueous NH4PF6 solution was added to the
filtrate, the volume of the mixture was then reduced under
vacuum to ∼10 mL. The orange-red precipitate was collected
by filtration through Celite, washed with water, diethyl ether,
and recrystallized from acetonitrile/water (1/2) to afford a red
powder. Yield 0.1 g, 91%. δH (500 MHz, (D6)DMSO) 9.57 (2H,
4ꢀ-{p-(1,4,7,10-Tetraazacyclododec-1-ylmethyl)phenyl}-
2,2ꢀ:6ꢀ,2ꢀ-terpyridine (cynt, 2)
Amodifiedliteratureprocedure[25] wasadoptedfortheprepa-
ration of this ligand. A solution of 6 (0.40 g, 1.0 mmol) in dry
CH2Cl2 (20 mL) under Ar was added dropwise to a stirred solu-
tion of 1,4,7,10-tetraazacyclododecane[41,42] (cyclen) (0.86 g,
5 mmol) in dry CH2Cl2 (20 mL). Et3N (5 drops) was added,
and the mixture was heated at 30◦C for 24 h. The reaction mix-
ture was cooled to room temperature and washed with water
(3 × 10 mL). The aqueous layer was kept aside to recover the
excess cyclen. The organic phase was collected, dried with
MgSO4, filtered, and the solvent was removed by rotary evapora-
tion.The crude material was purified by column chromatography
(Al2O3, eluting with 1–2% MeOH in CH2Cl2) to afford a glassy
white solid. Yield 0.237 g, 48%. δH (300 MHz, CDCl3) 8.74
ꢀ
ꢀ
ꢀ
ꢀ
s, H3 (ttp), H5 (ttp)), 9.56 (2H, s, H3 (dint), H5 (dint)), 9.21
ꢀ
ꢀꢀ
(4H, d, H3(dint, ttp), H3 (dint, ttp)), 8.50–8.47 (4H, m, H2 (ttp,
ꢀꢀ
ꢀ
dint), H6 (ttp, dint)), 8.18–8.15 (4H, m, H4(dint, ttp), H4 (dint,
ꢀꢀ
ꢀꢀ
ꢀꢀ
ttp)), 7.83 (2H, d, H3 (ttp), H5 (ttp)), 7.69 (2H, d, H3 (dint),
ꢀꢀ
ꢀ
H5 (dint)), 7.66–7.63 (4H, m, H6(dint, ttp), H6 (dint, ttp)), 7.39–
ꢀ
7.36 (4H, m, H5(dint, ttp), H5 (dint, ttp)), 3.92 (2H, s, H7),
ꢀ
ꢀ
3.85 (4H, m, H02, H02 ), 2.71 (4H, m, H01, H01 ), 2.62 (3H, s,
CH3). νmax (KBr)/cm−1 3660m, 3286w, 3082w, 2908w, 2846w,
1693m, 1609m, 1531w, 1477m, 1427w, 1408m, 1362w, 1288w,
1246w, 1196w, 1165w, 1130w, 1088w, 1030w, 972w, 845ssh,
ꢀ
ꢀ
(2H, s, H5 , H3 ), 8.72 (2H, d), 8.68 (2H, d), 7.91–7.85 (4H, m),

Terpyridyl-Polyamine Bridging Ligands
677
787s, 752m, 702w, 656w, 621w, 559s, 513m, 486w, 424w, 405m.
m/z (ESI) 497.6301 (11%, [M + H − (PF6)]2+), 424.6406,
(22, [M − 2(PF6)]2+), 283.4246 (100, [M + H − 2(PF6)]3+).
λmax/nm (ε/L mol−1 cm−1) 215.1 (32358), 224.9 (30968), 245.0
(33576), 255 (32904), 500.0 (5319). (Found: C 44.78, H 3.55,
N 9.56. Anal. Calc. for C48H46F18N9P3Ru (1284.90): C 44.87,
H 3.61, N 9.81%.)
3.80, N 9.50. Anal. Calc. for C51H48F18N9OP3Ru (1338.95):
C 45.75, H 3.61, N 9.41%.)
[(ttp)Ru(ptmtb)](PF6)3 (20)
Yield 0.043 g, 78%. δC (75 MHz, CD3CN) 159.21, 159.10,
156.69, 156.28, 153.42, 149.43, 147.56, 141.99, 140.10, 139.02,
135.40, 134.88, 134.82, 131.27, 129.66, 129.48, 129.30, 128.67,
128.54, 128.42, 125.63, 125.53, 122.68, 122.35, 84.35, 71.13,
62.23, 61.10, 55.43, 55.06, 53.28, 53.21, 49.87, 47.69, 43.46,
21.43, 19.83, 19.67. m/z (ESI) 557.2206 (29%, [M − 2(PF6)]2+),
323.1544 (100, [M − 3(PF6)]3+). νmax (KBr)/cm−1 3651w,
2949w, 2843w, 1655w, 1607m, 1524w, 1477m, 1466m, 1431m,
1406m, 1384m, 1356w, 1246w, 1196w, 1144w, 1086w, 1030w,
845ssh, 789s, 754m, 735w, 656w, 557ssh, 492w, 480w, 448w,
421w. λmax/nm 285.0, 295.0, 305.0, 490.0.
[(ttp)Ru(L)](PF6)2
The following general method was used in the synthesis of
[(ttp)Ru(L)](PF6)2 complexes. To a solution of [Ru(ttp)Cl3], in
dry MeOH, was added an equimolar amout of the appropriate
ligand and 10 drops of N-methylmorpholine. The solution was
heated at reflux for 1 h under Ar. The deep red solution was
cooled to room temperature before it was filtered to remove any
unreacted materials and an excess methanolic solution of ammo-
nium hexafluorophosphate was added to the filtrate to precipitate
the product complexes. The dark red precipitate was dissolved
in CH3CN, and then the solution was taken to dryness under
vacuum and the residue was purified by column chromatogra-
phy (SiO2 eluting with CH3CN/saturated KNO3 solution/H2O,
14/0.5/1).An excess of NH4PF6 was added to the major red frac-
tion and the solution was reduced in volume under vacuum. The
precipitate was collected by filtration over Celite, before it was
dissolved in CH3CN, and evaporated to dryness under vacuum
to afford [(ttp)Ru(L)](PF6)2 as a red powder.
[(ttp)Ru(cymt)](PF6)2 (15)
Yield 0.082–0.100 g, 25–31%. δH (500 MHz, (D6)acetone)
ꢀ
ꢀ
ꢀ
9.513 (2H, s, H3 (ttp), H5 (ttp)), 9.508 (2H, s, H3 (cymt),
ꢀ
ꢀ
H5 (cymt)), 9.16–9.12 (4H, m, H3(cymt, ttp), H3 (cymt, ttp)),
ꢀꢀ
ꢀꢀ
ꢀꢀ
8.57 (2H, d, H2 (ttp), H6 (ttp)), 8.39 (2H, d, H2 (cymt),
ꢀꢀ
ꢀ
H6 (cymt)), 8.21–8.16 (4H, m, H4(cymt, ttp), H4 (cymt, ttp)),
ꢀ
7.93–7.89 (4H, m, H6(cymt, ttp), H6 (cymt, ttp)), 7.85 (2H,
ꢀꢀ
ꢀꢀ
ꢀꢀ
ꢀꢀ
d, H3 (ttp), H5 (ttp)), 7.69 (2H, d, H3 (cymt), H5 (cymt)),
ꢀ
7.47–7.43 (4H, m, H5(cymt, ttp), H5 (cymt, ttp)), 4.35 (2H,
s, H7), 3.71–314 (20H, m, cyclam), 2.64 (3H, s, CH3).
δC (75 MHz, (D6)DMSO) 158.83, 158.78, 156.09, 155.97,
152.89, 152.83, 148.57, 147.86, 141.12, 138.43, 136.74, 136.57,
133.98, 131.80, 130.45, 128.38, 128.00, 127.83, 125.06, 124.99,
121.64, 121.35, 54.60, 52.45, 51.63, 50.48, 49.85, 48.30, 47.53,
45.50, 45.27, 24,89, 22.36, 20.71. νmax (KBr)/cm−1 3709w,
3720w, 2926m, 2858m, 1695w, 1653w, 1605m, 1539w, 1520w,
1468m, 1431m, 1408m, 1366w, 1288w, 1086w, 1030w, 845ssh,
789s, 756m, 741w, 721w, 656w, 623w, 592w, 557ssh, 538w,
519w, 480w, 447w, 421m, 407w. m/z (ESI) 546.2617 (22%,
[M + H − (PF6)]2+), 473.2755 (6, [M − 2(PF6)]2+), 315.8028
(100, [M + H − 2(PF6)]3+). λmax/nm 244.0, 286.0, 310.0, 490.0.
[(ttp)Ru(bpat)](PF6)2 (13)
Yield 0.042 g, 17%. δH (500 MHz, (D6)acetone) 9.53 (2H, s,
ꢀ
ꢀ
ꢀ
ꢀ
H3 (ttp), H5 (ttp)), 9.49 (2H, s, H3 (bpat), H5 (bpat)), 9.17–914
ꢀ
(4H, m, H3(bpat, ttp), H3 (bpat, ttp)), 8.95 (2H, d, H04(bpat),
ꢀ
ꢀꢀ
ꢀꢀ
H04 (bpat)), 8.43 (2H, d, H2 (bpat), H6 (bpat)), 8.37 (2H, d,
ꢀꢀ
ꢀꢀ
ꢀ
H2 (ttp), H6 (ttp)), 8.22–8.19 (4H, m, H4(bpat, ttp), H4 (bpat,
ꢀ
ꢀꢀ
ttp)), 8.16 (2H, m, H06(bpat), H06 (bpat)), 7.99 (2H, d, H3 (bpat),
ꢀꢀ
ꢀ
H5 (bpat)), 7.93 (2H, d, H6(bpat or ttp), H6 (bpat or ttp)),
ꢀ
7.90 (2H, d, H6(bpat or ttp), H6 (bpat or ttp)), 7.84 (2H, d
ꢀ
ꢀꢀ
ꢀꢀ
H07(bpat), H07 (bpat)), 7.70 (2H, d, H3 (ttp), H5 (ttp)), 7.66
ꢀ
(2H, m, H05(bpat), H05 (bpat)), 7.47–7.43 (4H, m, H5(bpat, ttp),
ꢀ
ꢀ
H5 (bpat, ttp)), 4.53 (4H, s, H01, H01 ), 4.45 (2H, s, H7), 2.65
(3H, s, CH3). δC (75 MHz, CD3CN) 159.22, 159.16, 156.91,
156.48, 156.33, 153.41, 149.34, 148.55, 148.01, 141.97, 140.67,
139.47, 138.98, 137.57, 134.90, 131.66, 131.26, 128.93, 128.66,
128.47, 128.41, 125.54, 125.49, 125.03, 124.80, 122.46, 122.33,
59.38, 58.61, 21.43. νmax (KBr)/cm−1 3647w, 3020w, 1607m,
1574w, 1468m, 1431m, 1406m, 1288w, 1248w, 1086m, 1030w,
847ssh, 791m, 756w, 667w, 656w, 619w, 557s, 529w, 513w,
492m, 480w, 465w, 446m, 422m, 418w. m/z(ESI)545.6792(5%,
[M + H − (PF6)]2+), 472.7060 (19, [M − 2(PF6)]2+), 315.4781
(100, [M + H − 2(PF6)]3+). λmax/nm 285.0, 310.0, 490.0.
[(ttp)Ru(cynt)](PF6)2 (14)
Yield 0.084 g, 26%. δH (500 MHz, (D6)acetone) 9.58 (2H,
s), 9.57 (2H, s), 9.25–9.21 (4H, m), 8.55–8.47 (4H, m), 8.20–
8.15 (4H, m), 7.86 (2H, d), 7.70–7.66 (6H, m), 7.43–7.39 (4H,
m), 4.07 (2H, s, H7), 3.37–2.99 (19H, cyclen), 2.60 (3H, s,
CH3). δC (75 MHz, (D6)DMSO)158.27, 158.22, 155.90, 155.27,
155.18, 152.37, 149.56, 147.17, 146.94, 140.48, 138.27, 137.81,
135.71, 133.39, 131.20, 130.23, 128.05, 127.79, 127.19, 125.08,
124.84, 121.43, 120.99, 55.47, 47.57, 45.08, 42.53, 42.32,
21.18. m/z (ESI) 532.4 (12%, [M + H − 4(PF6)]2+), 459.4 (7,
[M − 2(PF6)]2+), 306.6 (100, [M + H − 2(PF6)]3+). λmax/nm
285.0, 305.0, 490.0.
[(ttp)Ru(cttpH)](PF6)3
Yield 0.45 g, 53%. δH (300 MHz, (D6)acetone) 9.53 (4H,
s), 9.17–914 (4H, m), 8.50–8.36 (4H, m), 8.26–8.00 (5H, m),
7.97–7.92 (8H, m), 7.70 (2H, d), 7.47–7.43 (4H, m), 4.26–
4.18 (2H, (AB), PhCH2N), 3.18–412 (12H, macrocycle), 2.65
(3H, CH3). νmax (KBr)/cm−1 3653m, 1670m, 1607m, 1578w,
1477m, 1466m, 1431m, 1406m, 1385s, 1290w, 1246w, 1194w,
1163w, 1084w, 1055w, 1029w, 970w, 847ssh, 789s, 756m, 733w,
669w, 656w, 617w, 557ssh, 509w, 500w, 480w, 446w, 422m.
m/z (ESI) 1048.3851 (0.5%, [M − (PF6)]+), 524.7050 (29,
[M + H − (PF6)]2+), 451.6993 (29, [M − 2(PF6)]2+), 301.4705
(100, [M + H − 2(PF6)]3+). λmax/nm (ε/L mol−1 cm−1) 285.0
(32 115), 305.0 (34 418), 490.0 (12 744). (Found: C 45.34, H
[(ttp)Ru(tcnt)](NO3)2 (18)
The complex precursor [(ttp)Ru(cttp)](PF6)3 (0.4 g,
0.3 mmol) in acetone (10 mL) was subjected to base hydrolysis
by heating the solution at reflux with a solution of KOH (1 g,
18 mmol) in water (10 mL) for 3 days. The reaction progress
was monitored using TLC and 1H NMR spectroscopy. The reac-
tion mixture was cooled to room temperature, before the acetone
was removed from the solution by rotary evaporation. The pre-
cipitate was collected by filtration over Celite and the residue
was purified by column chromatography (SiO2 eluting with
CH3CN/saturated KNO3 solution/H2O, 7/0.5/1). The major red

678
R. Zibaseresht, A. M. Downward, and R. M. Hartshorn
ꢀ ꢀꢀ
m, H6(cymt, ttp), H6 (cymt, ttp)), 7.69 (2H, d, H3 (cymt),
fraction was collected, and taken to dryness by rotary evap-
oration. The complex was then dissolved in a small amount
of MeOH, and then filtered through Celite to remove KNO3.
This was repeated three times. The solution was taken to dry-
ness on vacuum, then was recrystallized by slow evaporation
of the MeOH/benzene (1/2) solution of the complex. The pre-
cipitate was filtered, washed well with benzene, diethyl ether,
and air-dried to afford a red-orange powder. Yield 0.2 g, 50%.
The unreacted starting materials were also collected and reused.
ꢀꢀ
ꢀ
H5 (cymt)), 7.48–7.43 (4H, m, H5(cymt, ttp), H5 (cymt, ttp)),
4.38 (2H, s, H7), 4.18–2.24 (20H, m, cyclam), 2.64 (3H, s, CH3).
δC (75 MHz, (D6)acetone) 158.67, 158.60, 156.01, 155.76,
ꢀꢀ
ꢀꢀ
152.69 (2C, C3 (ttp), C5 (ttp)), 148.53, 147.40, 140.87, 138.31
ꢀ
(4C, C4(cymt, ttp), C4 (cymt, ttp)), 138.07, 134.00 (2C, C6(cymt
ꢀ
ꢀ
or ttp), C6 (cymt or ttp)), 133.91 (2C, C6(cymt or ttp), C6 (cymt
ꢀꢀ
ꢀꢀ
or ttp)), 132.05, 130.33 (2C, C3 (cymt), C5 (cymt)), 128.39 (2C,
ꢀꢀ
ꢀꢀ
ꢀ
C2 (ttp), C6 (ttp)), 127.95(2C, C5(cymtorttp), C5 (cymtorttp)),
ꢀ
ꢀ
ꢀ
δH (500 MHz, (D6)DMSO) 9.59 (2H, s, H3 (tcnt), H5 (tcnt)),
127.88 (2C, C5(cymt or ttp), C5 (cymt or ttp)), 127.81 (2C, d,
ꢀ
ꢀ
ꢀꢀ ꢀꢀ ꢀ
C2 (cymt), C6 (cymt)), 124.92 (4C, m, C3(cymt, ttp), C3 (cymt,
9.57 (2H, s, H3 (ttp), H5 (ttp)), 9.23–9.21 (4H, m, H3(tcnt, ttp),
ꢀ
ꢀꢀ
ꢀꢀ
ꢀ ꢀ ꢀ
ttp)), 121.80 (2C, C3 (ttp), C5 (ttp)), 121.24 (2C, C3 (cymt),
H3 (tcnt, ttp)), 8.55 (2H, d, H2 (tcnt), H6 (tcnt)), 8.48 (2H, d,
ꢀꢀ
ꢀꢀ
ꢀ
ꢀꢀ
ꢀ
H2 (ttp), H6 (ttp)), 8.17–8.16 (4H, m, H4(tcnt, ttp), H4 (tcnt,
C5 (cymt)), 56.27, 53.75, 52.77, 52.24, 51.87, 50.66, 49.58,
48.37, 46.58, 27.20, 24.75, 20.65 (CH3). νmax (KBr)/cm−1
2924m, 2855w, 1607w, 1558w, 1466w, 1406m, 1385m, 1271ssh,
1088w, 1028w, 847ssh, 789m, 758w, 648w, 594w, 559m,
515w, 471w, 446w, 434w, 407w. m/z (ESI) 621.2722 (48%,
[M − 2(PF6)]2+), 365.8482 (100, [M − 3(PF6)]3+). λmax/nm
285.0, 310.0, 490.0. (Found: C 41.91, H 3.97, N 9.84. Anal.
Calc. for C54H53CoF18N12O4P3Ru·3H2O·O(C2H5)2 (1660.16):
C 41.96, H 4.37, N 10.12%.)
ꢀꢀ
ꢀꢀ
ttp)), 7.88 (2H, d, H3 (tcnt), H5 (tcnt)), 7.69 (2H, d, H3 (ttp),
ꢀꢀ
ꢀ
H5 (ttp)), 7.66–7.64 (4H, m, H6(tcnt, ttp), H6 (tcnt, ttp), 7.40–
ꢀ
7.37 (4H, m, H5(tcnt, ttp), H5 (tcnt, ttp)), 4.08 (2H, s, H7), 3.56
(4H, br, H10, H10 ), 3.27 (4H, br, H9, H9 ), 3.03 (4H, br, H8, H8 ),
2.62 (3H, s, CH3). δC (75 MHz, (D6)DMSO) 158.21, 158.14,
155.24, 155.13, 152.31 (C6, C6 (tcnt, ttp)), 147.04, 146.65,
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
140.48, 138.18 (C4, C4 (tcnt, ttp)), 135.38, 133.26, 130.91
ꢀꢀ
ꢀꢀ
ꢀꢀ
ꢀꢀ
ꢀꢀ
ꢀꢀ
(C3 , C5 (tcnt)),130.15 (C3 , C5 (ttp)), 127.84 (C2 , C6 (tcnt)),
ꢀꢀ
ꢀꢀ
ꢀ
ꢀ
127.68 (C3 , C5 (ttp)), 124.97 (C3, C3 (tcnt, ttp)), 121.17 (C3 ,
ꢀ
ꢀ
ꢀ
ꢀ
C5 (tcnt)), 120.86 (C3 , C5 (ttp)), 58.47 (C7), 48.82 (C8, C8 ),
[(ttp)Ru(cymt)Co(Cl)2]Cl3
ꢀ
ꢀ
44.19 (C9, C9 ), 43.16 (C10, C10 ), 21.12 (CH3).The product was
also isolated as its PF6− salt. νmax (KBr)/cm−1 3655m, 3000mbr,
1607m, 1533w, 1522w, 1479m, 1466m, 1431m, 1406m, 1358w,
1288w, 1246w, 1194w, 1163w, 1121w, 1084w, 1055w, 1030m,
968w, 847ssh, 789ssh, 754m, 741w, 721w, 656w, 619w, 557ssh,
509w, 480w, 444w, 434w, 422m. m/z (ESI) 510.6956 (23%,
[M − 2(PF6)]2+), 292.1342 (100, [M − 3(PF6)]3+). λmax/nm
285.0, 310.0, 490.0. (Found: C 39.22, H 3.63, N 8.69. Anal.
Calc. for C50H49F24N9P4Ru·3H2O (1510.96): C 39.75, H 3.67,
N 8.34%.)
All operations were carried out in darkness. To an acetone
solution of complex 24 (0.10 g, 0.065 mmol) was added 6 M
HCl (5 mL). The reaction mixture was heated on the steam bath
until a precipitate was formed. The red microcrystalline mate-
rial was collected and washed well with acetone and air-dried.
Recrystallization was achieved by vapour diffusion of diethyl
ether into MeOH solution of the complex. A red precipitate
formed, was collected by filtration though Celite, washed well
with diethyl ether, and redissolved in MeOH. The solvent was
removed on the rotary evaporator to give a red powder. Yield
0.041 g, 53%. δC (75 MHz, CD3OD) 160.00, 159.94, 157.27,
157.01, 153.60, 153.52, 150.53, 149.32, 142.35, 139.68, 138.92,
135.40, 135.29, 131.62, 129.53, 129.24, 129.15, 126.49, 126.34,
123.16, 122.75, 57.72, 57.44, 54.77, 54.76, 53.85, 52.86, 50.74,
29.11, 26.57, 21.70. m/z (ESI) 556.2232 (17%, [M − 2Cl]2+),
359.1535(100, [M − 3Cl]3+). νmax (KBr)/cm−1 3398br, 3051br,
2939m, 2893m, 1720m, 1608s, 1535w, 1477s, 1461s, 1427s,
1412ssh, 1285w, 1246m, 1200m, 1165w, 1130m, 1087m, 1030s,
984w, 953w, 910w, 883w, 814m, 791ssh, 756m, 732w, 702w,
656w, 621w, 509m, 444m, 424w. λmax/nm 285.0, 310.0, 490.0.
[(ttp)Ru(mptmtb)](I)(PF6)3 (21)
To the complex [(ttp)Ru(ptmtb)](PF6)3, 20 (0.5368 g,
0.38 mmol), in CH3CN (50 mL) was added CH3I (0.5 mL). The
solution was stirred at room temperature for 72 h. The remain-
ing CH3I and solvent were removed on a rotary evaporator to
give a red solid. Yield 0.5547 g, 95%. δH (500 MHz, CD3CN)
9.086 (4H, d), 8.729 (4H, t), 8.419 (2H, d), 8.185 (2H, d), 8.01–
7.9 (6H, m), 7.646 (2H, d), 7.5–7.48 (4H, m), 7.249 (4H, m),
5.288 (1H, d), 4.81 (1H, d), 4.35 (2H, s), 3.8–2.8 (20H, m,
cyclam), 3.411 (3H, s), 2.64 (3H, s). m/z (ESI) 637.27 (0.5%,
[M − (PF6) − (I)]2+), 376.49 ([M − 2(PF6) − (I)]3+).
[(ttp)Ru(cymt)Co(NO2)2](PF6)3 (24)
References
All operations were carried out in darkness. To complex 15
(0.1 g, 0.08 mmol) in acetone (5 mL) was added Na3[Co(NO2)6]
(0.032 g, 0.08 mmol) in water (2 mL). Et3N (10 drops) was
added. The mixture was gently heated at 50◦C for 4–6 h. The
reaction mixture was cooled to room temperature and excess
NH4PF6 was added. The precipitate was collected by filtration
throughCeliteandwashedwithwater, diethylether, andair-dried
to afford a red powder. Further purification was achieved by col-
umn chromatography over silica eluting with CH3CN/saturated
KNO3 solution/H2O (10/1/2). The major orange-red band was
collected as its PF−6 salt as a red-orange powder. Yield 0.103 g,
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ꢀ
ꢀ
84%. δH (500 MHz, (D6)acetone) 9.52 (2H, s, H3 (ttp), H5 (ttp)),
ꢀ
ꢀ
9.50 (2H, s, H3 (cymt), H5 (cymt)), 9.16–9.13 (4H, m, H3(cymt,
ꢀ
ꢀꢀ
ꢀꢀ
ttp), H3 (cymt, ttp)), 8.56 (2H, d, H2 (ttp), H6 (ttp)), 8.41 (2H,
ꢀꢀ
ꢀꢀ
d, H2 (cymt), H6 (cymt)), 8.20–8.17 (4H, m, H4(cymt, ttp),
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ꢀ
ꢀꢀ
ꢀꢀ
H4 (cymt, ttp)), 7.94 (2H, d, H3 (ttp), H5 (ttp)), 7.91 (4H,

Terpyridyl-Polyamine Bridging Ligands
679
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