Unusual coordination behaviour of the ferrocenyl-terpyridine ligand with group 11 complexes

Article abstract of DOI:10.1139/V08-148

Complexes of the ligand Fcterpy (Fcterpy = 4′-ferrocenyl-2,2′: 6′,2′-terpyridine) with group 11 metals display different coordination modes. The reaction with complexes [Cu(NO₃)(PPh ₃)₂] or [M(OTf)(PR₃)] (OTf =

Full text of DOI:10.1139/V08-148

341
Unusual coordination behaviour of the ferrocenyl-
terpyridine ligand with group 11 complexes1
Javier E. Aguado, M. Concepción Gimeno, Peter G. Jones, and Antonio Laguna
Abstract: Complexes of the ligand Fcterpy (Fcterpy = 4′-ferrocenyl-2,2′:6′,2′-terpyridine) with group 11 metals display
different coordination modes. The reaction with complexes [Cu(NO3)(PPh3)2] or [M(OTf)(PR3)] (OTf = trifluoromethyl-
sulphonate) gives the species [M(Fcterpy)(PR3)]X (M = Cu, X = PF6, PR3 = PPh3 (1); M = Ag, X = OTf, PR3 = PPh3
(2), PPh2Me (3); M = Au, X = OTf, PR3 = PPh3 (4)) in which the ligand is coordinated as a tridentate chelate to the
metal. Treatment with [Cu(NCMe)4]PF6 or Ag(OTf) in 1:1 molar ratio gives the dinuclear complexes [M2(Fcterpy)2]X2
(M = Cu (5), Ag (6)), in which the ligand is tetradentate because the central pyridine group is bonded to two metals.
The reaction with the gold(I) complex [Au(C6F5)(tht)] (tht = tetrahydrothiophene) leads to the first example of a
terpyridine ligand bonded to three metal atoms, [Au3(C6F5)3(Fcterpy)] (7); in the product of the corresponding reaction
with the gold(III) derivative [Au(C6F5)3(OEt2)] to give [Au(C6F5)3(Fcterpy)] (8), the ligand is monodentate, which is
also unusual for a terpyridine ligand.
Key words: copper, silver, gold, terpyridine, ferrocene derivatives
Résumé : Les complexes du ligand Fcterpy [Fcterpy = 4′-ferrocényl-2,2′:6′,2′-terpyridine] avec les métaux du groupe
11 présentent divers modes de coordination. Les réactions avec des complexes [Cu(NO3)(PPh3)2] ou [M(OTf)(PR3)]
(Otf = trifluorométhylsulfonate) conduisent à des espèces [M(Fcterpy)(PR3)]X [M = Cu; X = PF6; PR3 = PPh3 (1);
M = Ag; X = OTf; PR3 = PPh3 (2); PPh2R (3); M = Au; X = OTf; PR3 = PPh3 (4)] dans lesquels le ligand est coor-
diné au métal sous la forme de chélate tridentate. Le traitement avec du [Cu(NCME)4]PF6 ou du Ag(OTf), dans un
rapport molaire de 1:1, conduit à la formation de complexes binucléaires [Me2(Fcterpy)2]X2 (M = Cu (5); Ag (6)] dans
lesquels le ligand est tétradentate parce que le groupe pyridine central est lié à deux métaux. La réaction avec le
complexe d’or(I) [Au(C6F5)(tht)] (tht = tétrahydrothiophène) conduit au premier exemple d’un ligand terpyridine lié à
trois atomes métalliques, [Au3(C6F5)3(Fcterpy)] (7); dans le produit de la réaction correspondante avec le dérivé
d’or(III) [Au(C6F5)3(OEt2)] conduisant à la formation de [Au(C6F5)3Fcterpy)] (8), le ligand est sous la forme monoden-
tate qui est inhabituelle pour un ligand terpyridine.
Mots-clés : cuivre, argent, or, terpyridine, dérivés du ferrocène.
[Traduit par la Rédaction] Aguado et al. 347
Introduction
ligand with a non-coordinating residue (2). In the last few
years, interesting spiral arrays have been prepared with these
ligands that, by twisting, can accommodate more than one
metal center. Thus, some examples have been prepared with
silver in which the terpy is bonded to two different metal
centers in a supramolecular structure (3). We have previ-
ously communicated another coordination mode in which
the three nitrogen atoms are bonded to three different metals
in the complex [Au3(C6F5)3(Fcterpy)] (4). Few terpyridine
complexes of gold have been described and these are
gold(III) derivatives, such as [AuX(Rterpy)]2+ (X = Cl, OH;
The coordination chemistry of terpyridine ligands with
various metals has been the subject of numerous studies, in-
spired by the exciting photophysical properties of metal–
polypyridyl complexes (1). In these compounds, the
terpyridine generally acts as a chelating planar tridentate
ligand; only in some examples does it act as a bidentate
Received 21 May 2008. Accepted 10 September 2008.
Published on the NRC Research Press Web site at
canjchem.nrc.ca on 6 January 2009.
2
R = H, SMe, PhOMe) (5–8), or [Au(CN)2Br(η -terpy)] (9)
Dedicated to Professor Richard Puddephatt.
(terpy = terpyridine), in which the ligand acts a tridentate or
bidentate chelate. For silver and copper, more examples
have been described including complexes of the type
[M(PR3)2(terpy)]X (M = Cu, Ag) (10).
Here we report complexes with the group 11 metals and a
substituted terpyridine ligand, 4′-ferrocenyl-2,2′:6′,2′-
terpyridine (Fcterpy) (11). Several coordination modes have
been achieved, including tridentate chelate in complexes of
the type [M(Fcterpy)(PR3)]X (M = Cu, Ag, Au), tetradentate
in the homoleptic species [M2(Fcterpy)2]X2 (M = Cu, Ag),
which represent the first examples of dinuclear rather than
J.E. Aguado, M.C. Gimeno,2 and A. Laguna. Departamento
de Química Inorgánica, Instituto de Ciencia de Materiales de
Aragón, Universidad de Zaragoza – C.S.I.C.,
E-50009 Zaragoza, Spain.
P.G. Jones. Institut für Anorganische und Analytische
Chemie der Technischen Universität, Postfach 3329, D-38023
Braunschweig, Germany.
1This article is part of a Special Issue dedicated to Professor
R. Puddephatt.
2Corresponding author (e-mail: gimeno@unizar.es).
Can. J. Chem. 87: 341–347 (2009)
doi:10.1139/V08-148
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Can. J. Chem. Vol. 87, 2009
Scheme 1. Synthesis of the Fcterpy ligand.
Table 1. Bond lengths and angles for the
ligand Fcterpy.
Bond lengths (Å)
N(1)–C(5)
1.337(3)
1.346(3)
1.335(3)
1.344(4)
1.336(3)
1.338(3)
N(1)–C(1)
N(2)–C(10)
N(2)–C(6)
N(3)–C(15)
N(3)–C(11)
Bond angles (°)
C(5)-N(1)-C(1)
C(15)-N(3)-C(11)
N(1)-C(1)-C(2)
N(1)-C(1)-C(6)
N(1)-C(5)-C(4)
N(2)-C(6)-C(7)
N(2)-C(6)-C(1)
C(10)-N(2)-C(6)
N(2)-C(10)-C(9)
N(3)-C(11)-C(10)
N(2)-C(10)-C(11)
N(3)-C(15)-C(14)
116.8(2)
116.9(2)
122.4(2)
116.6(2)
124.4(3)
122.8(2)
115.9(2)
117.6(2)
122.7(2)
116.7(2)
116.7(2)
124.5(3)
Fig. 1. Structure of compound Fcterpy showing the atom label-
ling scheme. Displacement parameter ellipsoids represent 50%
probability surfaces. Radii are arbitrary; H atoms are omitted for
clarity.
plexes [Cu(PPh3)(Fcterpy)]NO3 (1), [Ag(PR3)(Fcterpy)]OTf
(PR3 = PPh3 (2), PPh2Me (3)), or [Au(PPh3)(Fcterpy)]OTf
(4) (see Scheme 2). The IR spectra for these compounds
show the absorptions of the ferrocenyl terpyridine unit as
those arising from the aromatic pyridine and
cyclopentadienyl rings around 1607 (s), 1586 (s), 1104 (s),
and 820 (s) cm–1. In addition, complex 1 shows the absorp-
tions of the nitrate group at 1725 (w), 1090 (m), 1026 (m),
1000 (w), and 827 (m) cm–1 and complexes 2–4 show the
bands arising from the ionic trifluoromethylsulfonate anion
at around 1262 (vs), 1223 (m), 1147 (vs), and 1030 (vs) cm–1.
1
Because the H NMR spectra of all complexes show the
the usual polymeric derivatives, or monodentate in the
gold(III) compound [Au(C6F5)3(Fcterpy)].
presence of the ligand Fcterpy, it is useful to compare the
resonances with those present in the free ligand. The ligand
shows two multiplets for the α and β protons of the substi-
Results and discussion
tuted cyclopentadienyl group and
a singlet for the
The ligand 4′-ferrocenyl-2,2′:6′,2′-terpyridine (Fcterpy)
has been synthesized by aromatization of a 3-ferrocenyl-1-
bis(2-pyridyl)pentane-1,5-dione, previously obtained by
reaction of ferrocenaldehyde and 2-acetylpyridine, or by
aromatization of the corresponding enone with a pyridonium
iodide salt (see Scheme 1) as has been previously described
(11). The crystal structure of this ligand has been established
and the molecule is shown in Fig. 1. A selection of bond
lengths and angles are collected in Table 1. The overall bond
lengths and angles are within the normal values found in this
type of compound (12). The cyclopentadienyl rings are al-
most eclipsed. In the terpyridine moiety the aromatic rings
are almost coplanar themselves, but not with the
cyclopentadienyl ring; the dihedral angle formed by the ni-
trogen atoms and the cyclopentadienyl ring is 161.6°. The
nitrogen atoms of the external pyridine rings are pointed in
the opposite direction to that of the central one. This config-
uration changes upon coordination of the ligand.
unsubstituted cyclopentadienyl unit; the proton signals for
the terpyridine are a doublet of doublets for the pair 5–5′′, a
doublet of triplets for the pair 4–4′′, a singlet for 3′–5′, and
doublets for the pairs 3–3′′ and 6–6′′. The resonances for the
coordinated ligand in complexes 1–4 resemble those in the
free ligand but with a different chemical shift and not so
well defined, and in some cases the resonances overlap with
those of the phenylic protons. For complex 3, a doublet at
1.91 ppm for the methyl protons coupled to the phosphorus
atom is observed. The 31P{1H} NMR spectra shows a singlet
for complexes 1 and 4, whereas for compounds 2 and 3 a
broad resonance appears at room temperature and splits into
two doublets at –55 °C, because of the coupling of the
phosphorus atom with the two silver nuclei with spin 1/2,
109Ag (48.17%) and 107Ag (51.83%). The mass spectra show
in all the complexes the cationic molecular peak
[M(PR3)(Fcterpy)]+ at m/z = 742 (18%, 1), 786 (34%, 2),
724 (36%, 3), and 876 (45%, 4), although for the copper and
silver complexes the most abundant peaks correspond to the
species [M(Fcterpy)]+.
The reaction of the Fcterpy ligand with [Cu(NO3)(PPh3)2]
or [Ag(OTf)(PR3)] or [Au(OTf)(PPh3)] affords the com-
© 2008 NRC Canada

Aguado et al.
343
Scheme 2. (i) [Cu(NO3)(PPh3)2] or [Ag(OTf)(PR3)] or
[Au(OTf)(PPh3)]; (ii) [Cu(NCMe)4]PF6 or Ag(OTf); (iii) 3
[Au(C6F5)(tht)]; (iv) [Au(C6F5)3(OEt2)].
Fig. 2. Structure of the cation of compound 2 showing the atom
numbering scheme. Displacement parameter ellipsoids represent
30% probability surfaces. Radii are arbitrary; H atoms are omit-
ted for clarity.
Fig. 3. Structure of the cation of compound 3 showing the atom
numbering scheme. Displacement parameter ellipsoids represent
30% probability surfaces. Radii are arbitrary; H atoms are omit-
ted for clarity.
The silver complexes have been structurally characterized,
showing that the metal center is bonded to the three nitrogen
atoms of the terpyridine unit, although the shortest bond is
with the central nitrogen atom; we assume analogous struc-
tures for the copper and gold complexes. However in the
gold complex the metal could be far more strongly bonded
to the central nitrogen atom and make only very short con-
tacts with the others, given the high tendency of gold to
form two-coordinate derivatives. No crystal structure for
gold(I) complexes with terpyridine ligands has been carried
out, with the exception of the trinuclear complex 7. The
structures of complexes 2 and 3 have been established by
X-ray diffraction and are shown in Figs. 2 and 3, respec-
tively. A selection of bond lengths and angles are collected
in Tables 2 and 3. The structure for complex 2 shows that
the silver center coordinates to the three nitrogen atoms of
the terpyridine moiety and to the triphenylphosphine, and al-
though it is tetra-coordinated, the geometry is far from tetra-
hedral. The silver atom is located 0.11 Å out of the plane
formed by the four donor atoms, P, N11, N21, and N31, and
only 0.057 Å out of the trigonal plane of the P, N21, and
N31 atoms. The Ag–N distances are 2.302(4), 2.435(4), and
2.492(4) Å, the shortest being to the central nitrogen atom.
The angles N–Ag–P are 117.53(9) and 109.91(11)°, which
corresponds to normal values found in trigonal planar com-
plexes (13); consequently the N–Ag–N angles are very nar-
row, 68.98(13) and 68.35(14)°. Two of the phenyl rings are
disordered in mutually perpendicular positions, although this
disorder is not shown in Fig. 2. The structure of complex 3
is similar, with Ag–N distances 2.332(4), 2.421(4), and
2.488(5) Å, again with the shortest to the central pyridine
ring. The geometry around the silver center is more distorted
than in complex 2; the Ag atom lies 0.27 Å out of the plane
formed by the four coordinated atoms and 0.11 Å out of the
plane of the N1, N3, and P atoms. The phosphorus atom is
located further from the plane formed by the terpyridine and
the silver atom than in complex 2, with an N2–Ag–P angle
of 152.06(11)° compared to 158.65(9)° in 2. These struc-
tures are different from the previously reported complexes
of stoichiometry [M(terpy)(PPh3)2]+, which consist of dis-
crete monomers of distorted trigonal-bipyramidal geometry,
with the metal atoms coordinated to the distal terpyridine
pyridyl rings [Cu-N 2.386(3), 2.535(4); Ag–N 2.614(2),
2.561 (2)Å] in axial sites (10). The coordination spheres are
completed by the binding of the central pyridyl nitrogen at-
oms [Cu-N(2) 2.102(3), Ag–N(2) 2.457(2)Å] and two PPh3
phosphorus atoms, which together define the equatorial
planes.
The reaction of the ligand with an equimolar amount of
[Cu(NCMe)4]PF6 or Ag(OTf) gives compounds with the
stoichiometry [M(Fcterpy)]X (M = Cu, X = PF6 (5); M =
Ag, X = OTf (6)). The IR spectra show the typical absorp-
tions of the Fcterpy ligand; the copper species show the ab-
sorption of the hexafluorophosphate at 640 (s) cm–1, whereas
the silver derivative presents the absorptions for the
trifluoromethylsulfonate at 1259 (vs), 1223 (m), 1115 (vs),
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Can. J. Chem. Vol. 87, 2009
Table 2. Selected bond lengths and angles for
complex 2.
the ferrocenyl-terpyridine ligand has an unusual role; central
pyridine is bonded to the two silver atoms, in a coordination
mode described as “crevice” (see Scheme 1) that has only
recently been reported for silver (10). We assume a similar
structure for the copper species although we can not rule out
other possibilities.
Bond lengths (Å)
Ag–N(11)
Ag–N(31)
Ag–P
2.302(4)
2.435(4)
2.3710(14)
2.492(4)
The reaction of the ferrocenyl-terpyridine ligand with
three equivalents of [Au(C6F5)(tht)] in dichloromethane
Ag–N(21)
3
leads to the synthesis of the compound [Au3(C6F5)3(η -
Bond angles (°)
Fcterpy)] (7), which has been previously communicated and
represents the first example of a terpyridine ligand bonded to
three metal atoms (4) The treatment of the ligand with the
gold(III) derivative, [Au(C6F5)3(OEt2)], gives an orange solid
[Au(C6F5)3(Fcterpy)] (8). The IR spectrum shows the typical
absorptions arising from the pentafluorophenyl groups
bonded to gold(III) at 1509 (vs), 965 (vs), 821 (m), and 794
(vs) cm–1. The 19F NMR spectrum also confirms the pres-
ence of an Au(C6F5)3 moiety because six resonances appear,
three for the pentafluorophenyl rings in a mutually trans po-
sition and the other three for the other pentafluorophenyl
N(11)-Ag-P
158.65(9)
68.35(14)
68.98(13)
109.91(11)
117.53(9)
132.38(13)
N(11)-Ag-N(21)
N(11)-Ag-N(31)
P-Ag-N(21)
P-Ag-N(31)
N(31)-Ag-N(21)
Table 3. Selected bond lengths and angles for
complex 3.
Bond lengths (Å)
1
ring (ratio 2:1). The H NMR spectrum presents the reso-
Ag–N(2)
Ag–N(1)
Ag–P
2.332(4)
2.421(4)
2.3783(16)
2.488(5)
nances for the ferrocenyl-terpyridine, shifted compared to
the free ligand. The protons of the ferrocenyl and terpyridine
unit have the same pattern as in the free ligand and, conse-
quently, we assume a symmetrical coordination. Furthermore,
since gold(III) is mainly square planar and pentacoordination
is not easily achieved, we propose a coordination of the
gold(III) center to the central pyridine group.
Ag–N(3)
Bond angles (°)
N(2)–Ag–P
152.06(11)
67.72(15)
69.22(15)
111.19(11)
113.70(11)
134.47(14)
N(2)-Ag-N(3)
N(2)-Ag-N(1)
P-Ag-N(3)
Electrochemistry
The electrochemical behaviour of the ligand Fcterpy and
some of these complexes has been studied by cyclic
voltammetry at a platinum electrode in CH2Cl2. The ligand
Fcterpy undergoes a reversible one-electron oxidation pro-
cess at 0.64 eV; this is based on the ferrocene unit although
at higher potential than the ferrocene itself. The cyclic
voltammogram of the gold derivative 8, at a scan rate of
100 mV s–1, shows an essentially reversible wave arising
from the oxidation-reduction of the ferrocene moiety at slightly
lower potential than the free ligand, 0.61 eV. The copper(I)
and silver(I) compounds [M(PPh3)(Fcterpy)]+ show, in addi-
tion to the wave from the ferrocene oxidation at 0.54 and
0.59 eV, respectively, a more anodic irreversible wave that
can be assigned to the one electron oxidation of Cu+ to Cu2+
and Ag+ to Ag2+ at 0.70 and 1.12 eV. The dinuclear silver
derivative [Ag2(Fcterpy)2](OTf)2 also shows a quasi reversible
wave for the oxidation-reduction of the ferrocene moieties at
0.60 eV and it is possible to distinguish two oxidation waves
at 1.08 and 1.17 eV for the two Ag+ atoms.
P-Ag-N(1)
N(1)-Ag-N(3)
and 1029 (vs) cm–1. The 1H NMR spectra also exhibit differ-
ent ligand chemical shifts for the silver and copper deriva-
tives; the copper species shows a broad resonance at
8.2 ppm for all the protons of the Fcterpy ligand. In the mass
spectrum of complex
5
the peaks arising from
[Cu(Fcterpy)]+, [Cu2(Fcterpy)2]2+, and [Cu2(Fcterpy)](PF6)+
appear at m/z = 480 (100%), 960 (9%), and 1129 (15%); for
complex 6 similar peaks at m/z = 524 ([Ag(Fcterpy)]+, 100%),
941 ([Ag(Fcterpy)2]+, 12%), and 1119 ([Ag2(OTf)(Fcterpy)2]+,
4%) are observed. These data could imply a dinuclear struc-
ture with two metal atoms and two ferrocenyl-terpyridine
ligands. The previously reported complexes that contain a
terpyridine ligand and silver atoms are usually polymeric
species in which the silver center bonds asymmetrically to
the terpyridine units, giving a polymeric chain structure or a
helical structure for the ligand t-BuPh-terpy (14). In our
ligand the presence of a more bulky group, the ferrocenyl
unit, makes the structure different. Several crystals of com-
plex 6 proved to be of low quality, small and poorly diffract-
ing, but the molecule can be recognised in the structure
solution and corresponds to a dinuclear derivative in which
Experimental section3
Reagents and general procedures
Infrared spectra were recorded in the range 4000–200 cm–1
on a PerkinElmer 883 spectrophotometer using Nujol mulls
3 Supplementary data for this article are available on the journal Web site (canjchem.nrc.ca) or may be purchased from the Depository of
Unpublished Data, Document Delivery, CISTI, National Research Council Canada, Ottawa, ON K1A 0R6, Canada. DUD 3856. For more
information on obtaining material refer to cisti-icist.nrc-cnrc.gc.ca/cms/unpub_e.shtml. CCDC 688756–688758 contain the crystallographic
data for this manuscript. These data can be obtained, free of charge, via www.ccdc.cam.ac.uk/conts/retrieving.html (Or from the Cambridge
Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax +44 1223 336033; or deposit@ccdc.cam.ac.uk).
© 2008 NRC Canada

Aguado et al.
345
between polyethylene sheets. C, H, N, and S analyses were
carried out with a PerkinElmer 2400 microanalyzer. Mass
spectra were recorded on a VG Autospec, with the liquid
secondary-ion mass spectra (LSIMS) technique, using
nitrobenzyl alcohol as matrix. NMR spectra were recorded
on a Varian Unity 300 spectrometer and a Bruker ARX 300
spectrometer in CDCl3, unless otherwise stated. Chemical
shifts are cited relative to SiMe4 (1H, external), CFCl3 (19F,
external), and 85% H3PO4 (31P, external). Cyclic volt-
ammetric experiments were performed by employing an
EG&G PARC Model 273 potentiostat. A three-electrode
system was used, consisting of a platinum disk working
electrode, a platinum wire auxiliary electrode, and a satu-
rated calomel reference electrode. The measurements were
carried out in CH2Cl2 solutions with 0.1 mol/L Bu4NPF6 as
a supporting electrolyte. Under the present experimental
conditions, the ferrocenium–ferrocene couple was located at
0.47 V vs. SCE. The starting materials Fcterpy (11),
[Au(C6F5)(tht)] (15), [Ag(OTf)(PR3)] (16), [Cu(NO3)(PPh3)2]
(17), [Cu(NCMe)4]PF6 (17), and [Au(C6F5)3(OEt2)] (18)
were prepared according to published procedures.
[Au(OTf)(PPh3)] was obtained by reaction of [AuCl(PPh3)]
(19) with Ag(OTf) in dichloromethane and used in situ. All
other reagents were commercially available.
H3′,H5′), 7.98 (s, 2H, H3′,H5′), 8.37 (d, 2H, J(HH) = 3.91 Hz,
H6,H6′′). 31P NMR{1H, –55 °C) δ: –6.7 (2d, 1 P, J(109AgP) =
733 Hz, J(107AgP) = 631 Hz, PPh2Me). MS m/z: 724 (36%,
[Ag(PPh2Me)(Fcterpy)]+), 524 (100%, [Ag(Fcterpy)]+).
Anal.calcd. for C39H32AgF3FeN3O3PS: C 53.56, H 3.68, N
4.80, S 3.66; found: C 53.69, H 3.71, N 5.12, S 3.83.
Preparation of [Au(PPh3)(Fcterpy)]OTf (4)
To a solution of Fcterpy (0.041 g, 0.1 mmol) in 20 mL of
dichloromethane was added [Au(OTf)(PPh3)] (0.060 g,
0.1 mmol) and the mixture was left to react for 40 min.
Evaporation of the solvent to ca. 2 mL and addition of hexane
1
gave a deep red solid of complex 4; yield 65%. H NMR δ:
4.31 (s, 5H, C5H5), 4.67 (m, 2H, C5H4), 5.30 (m, 2H, C5H4),
7.2–7.5 (m, 15H + 2H, Ph + H5,H5′′), 7.89 (m, 2H,
H4,H4′), 8.59 (m, 2H, H6,H6′′), 8.32 (m, 2 H, H3,H3′′),
8.71 (s, 2H, H3′,H5′). 31P NMR{1H} δ: 33.6 (s, 1P, PPh3).
MS m/z: 876 (45%, [Au(PPh3)(Fcterpy)]+). Anal. calcd. for
C44H34AuF3FeN3O3PS: C 51.52, H 3.34, N 4.09, S 3.12;
found: C 51.74, H 3.44, N 4.10, S 3.31.
Preparation of [M2(Fcterpy)2]X2 (M = Cu, X =PF6 (5)
and M = Ag, X = OTf = (6))
To a solution of Fcterpy (0.041 g, 0.1 mmol) in 20 mL of
dichloromethane was added [Cu(NCMe)4]PF6 (0.038 g,
0.1 mmol), at 0 °C and under an argon atmosphere, or
Ag(OTf) (0.025 g, 0.1 mmol), and the mixture was left to re-
act for 30 min. Evaporation of the solvent to ca. 2 mL and
addition of hexane gave deep red solids of complexes 5 or 6.
Preparation of [Cu(PPh3)(Fcterpy)]NO3 (1)
To a solution of Fcterpy (0.041 g, 0.1 mmol) in 20 mL of
dichloromethane was added [Cu(NO3)(PPh3)2] (0.063 g,
0.1 mmol) under an argon atmosphere, and the mixture was
left to react for 40 min. Evaporation of the solvent to ca.
2 mL and addition of hexane gave a deep red solid of com-
1
Complex 5: yield 53%. H NMR δ: 4.10 (s, 5H, C5H5), 5.06
1
plex 1; yield 53%. H NMR δ: 4.09 (s, 5H, C5H5), 4.63 (m,
(m, 2H, C5H4), 4.52 (m, 2H, C5H4), 8.2 (m, 10H, terpy).
MS m/z: 1129 (15%, [Cu2(Fcterpy)2](PF6)+), 960 (9%,
[Cu2(Fcterpy)2]+), 480 (100%, [Cu(Fcterpy)]+). Anal. calcd.
for C50H38Cu2F12Fe2N6P2: C 47.98, H 3.06, N 6.71; found:
C 47.97, H 3.27, N 7.03. Complex 6: yield 61%. 1H NMR δ:
4.19 (s, 5H, C5H5), 4.65 (m, 2H, C5H4), 5.32 (m, 2H, C5H4),
7.43 (dq, 2H, J(HH) = 5.0, 1.1 Hz, H5,H5′′), 8.06 (dt, 2H,
J(HH) = 7.69, 1.71 Hz, H4,H4′), 8.31 (d, 2H, J(HH) = 5.0 Hz,
H6,H6′′), 8.48 (d, 2 H, J(HH) = 8.05 Hz, H3,H3′′), 8.51 (s,
2H, H3′,H5′). MS m/z: 1119 (4%, [Ag2(OTf)(Fcterpy)2]+),
941 (12%, [Ag2(Fcterpy)2]+), 524 (100%, [Ag(Fcterpy)]+).
Anal. calcd. for C52H38Ag2F6Fe2N6O6S2: C 46.31, H 2.84, N
6.23, S 4.75; found: C 46.55, H 3.02, N 6.37, S 4.66.
2H, C5H4), 5.0 (m, 2H, C5H4), 6.9–7.5 (m, 15H + 4H, Ph +
H5,H5′′ + H6,H6′′), 7.66 (t, 2H, J(HH) = 7.45 Hz, H4,H4′),
7.97 (d, 2H, J(HH) = 8.06 Hz, H3,H3′′), 8.01 (s, 2H,
H3′,H5′). 31P NMR {1H} δ: 1.2 (s, 1 P, PPh3). MS m/z: 742
(18%, [Cu(PR3)(Fcterpy)]+), 480 (100%, [Cu(Fcterpy)]+).
Anal.calcd.. for C43H34CuFeN4O3P: C 64.14, H 4.25, N
6.95; found: C 64.53, H 4.62, N 6.74.
Preparation of [Ag(PR3)(Fcterpy)]OTf (PR3 = PPh3 (2)
and PPh2Me (3))
To a solution of Fcterpy (0.041 g, 0.1 mmol) in 20 mL of
dichloromethane was added [Ag(OTf)(PPh3)] (0.051 g,
0.1 mmol) or [Ag(OTf)(PPh2Me)] (0.045 g, 0.1 mmol) and
the mixture was left to react for 40 min. Evaporation of the
solvent to ca. 2 mL and addition of hexane gave deep red
Preparation of [Au(C6F5)3(Fcterpy)] (8)
1
solids of complex 2 or 3. Complex 2: yield, 92%. H NMR
To a solution of Fcterpy (0.041 g, 0.1 mmol) in 20 mL of
dichloromethane was added [Au(C6F5)3(OEt2)] (0.077 g,
0.1 mmol) at 0 °C and under an argon atmosphere, and the
mixture was left to react for 40 min. Evaporation of the sol-
vent to ca. 2 mL and addition of hexane gave a deep red
δ: 4.10 (s, 5H, C5H5), 4.54 (m, 2H, C5H4), 5.08 (m, 2H,
C5H4), 7.2–7.4 (m, 15H, Ph), 7.45 (d, 2H, J(HH) = 7.33 Hz,
H5,H5′′), 7.97 (t, 2H, J(HH) = 7.69 Hz, H4,H4′), 8.17 (d,
2H, J(HH) = 4.17 H6,H6′′), 8.21 (s, 2H, H3′,H5′), 8.45 (d,
2 H, J(HH) = 7.92 Hz, H3,H3′′). 31P NMR {1H, –55 °C}
δ: 12.3 (2d, 1 P, J(109AgP) = 707, J(107AgP) = 615 Hz,
PPh3). MS m/z: 786 (34%, [Ag(PPh3)(Fcterpy)]+), 524 (100%,
[Ag(Fcterpy)]+). Anal. calcd. for C44H34AgF3FeN3O3PS:
C 56.43, H 3.65, N 4.48, S 3.42; found: C 56.57, H 3.70,
1
solid of complex 8; yield 63%. H NMR δ: 4.15 (s, 5H,
C5H5), 4.57 (m, 4H, C5H4), 5.04 (m, 4H, C5H4), 7.51 (m,
2H, H5,H5′′), 8.01 (s, 2H, H3′,H5′), 8.03 (m, 2H, H3,H3′′),
8.40 (m, 2H, H4, H4′), 8.69 (d, 2H, J(HH) = 5.13, H6,H6′′).
19F NMR δ: –121.6 (m, 6F, m-F), –156.4 (t, 2F, p-F, J(FF) =
21.12 Hz), –156.7 (t, 1F, p-F, J(FF) = 21.33 Hz), –160.8 (m,
4F, o-F), –161.9 (m, 2F, o-F). Anal. calcd. for
C43H19AuF15FeN3: C 46.30, H 1.71, N 3.76; found: C 46.25,
H 1.54, N 3.49.
1
N 4.72,S 3.20. Complex 3; yield 80%. H NMR δ: 1.91 (d,
3H, J(HP) = 6 Hz, Me), 4.45 (s, 5H, C5H5), 4.84 (m, 2H,
C5H4), 5.35 (m, 2H, C5H4), 7.2–7.4 (m, 10H, Ph), 7.41 (2H,
H5,H5''), 7.89 (t, 2H, J(HH) = 7.57 Hz, H4,H4'), 7.98 (s, 2H,
© 2008 NRC Canada

346
Can. J. Chem. Vol. 87, 2009
Table 4. X-ray data for the compound Fcterpy and complexes 2 and 3.
Compound
Formula
Mr
Fcterpy
C50H38Fe2N6
834.56
2·0.59 H2O
C44H35.19AgF3FeN3O3.6PS
947.25
Red tablet
0.40 × 0.20 × 0.20
Tetragonal
I41/a
3·1/2 CH2Cl2
C39.5H33AgClF3N3O3PS
916.89
Habit
Red prism
Red prism
0.40 × 0.30 × 0.25
Triclinic
Crystal size (mm)
Crystal system
Space group
0.20 × 0.20 × 0.12
Monoclinic
P21/c
P1
a (Å)
7.7987(8)
22.030(2)
11.3629(11)
90
29.326(3)
29.326(3)
18.561(2)
90
11.397(2)
12.093(2)
15.574(3)
108.38(3)
105.79(3)
98.61(3)
1893.8(6)
2
b (Å)
c (Å)
α (°)
β (°)
107.306(2)
90
90
γ (°)
90
15964(3)
16
1.577
1.007
7680
–100
50
V (Å3)
Z
1863.8(3)
2
D (Mg m–3)
µ (mm–1)
F(000)
T (°C)
2θmax
1.487
1.608
0.826
1.125
864
926
–173
–100
51
50
Reflections collected
Independent reflections
Transmissions
Rint
10 474
8828
7569
3462
7006
6469
0.8522–0.9074
0.052
302
0
0.09
0.039
0.936
0.499
0.704–0.816
0.035
466
393
0.088
0.043
0.822
0.599
0.885–0.968
0.032
482
2
0.131
0.05
0.917
1.36
Parameters
Restraints
wR(F2, all refl.)
R(I, > 2σ(I))
S
Max. ∆ρ (e Å–3)
Crystal structure determinations
References
Crystals were mounted in inert oil on glass fibers and
transferred to the cold gas stream of a Bruker Smart 1000
CCD (Fcterpy) or Siemens P4 (2, 3) diffractometer equipped
with a low-temperature attachment. Data were collected us-
ing monochromated Mo Kα radiation (λ = 0.710 73 Å) and
scan type ω, or ω and φ. Absorption corrections based on psi-
scans (2, 3) or multiple scans with the program SADABS
(20) (Fcterpy), were applied. The structures were refined on
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atoms were refined anisotropically. Hydrogen atoms were
included using a riding model. A special refinement was re-
quired for 2: Two rings of the PPh3 ligand are disordered
over two positions and were refined isotropically. A peak of
ca. 3 e/Å3 was interpreted as a partially occupied water site.
It is also involved in a contact of ca. 2.9 Å to itself, which
could represent an H bond. Further details of the data collec-
tion and refinement are given in Table 4.
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© 2008 NRC Canada