Heterometallic complexes with the mono and disubstituted [(4-pyridylamino)carbonyl]ferrocene ligands

Article abstract of DOI:10.1016/j.jorganchem.2012.05.013

The coordination chemistry of the ferrocene ligands [(4-pyridylamino) carbonyl]ferrocene (L1) and 1,1′-bis[(4-pyridylamino)carbonyl]ferrocene (L2) with group 11 metals and thallium has been studied, and several complexes with coordination of the metal to the pyridine nitrogen atom or to the pyridine and carbonyl group have been prepared. For the ligand L1 complexes such as [AuX(L1)] (X = Cl, C₆F₅), [M(PPh₃)(L1)]OTf (M = Au, Ag) (OTf = trifluoromethylsulfonate), [Ag(OTf)(L1)] or [M(L1) ₂]⁺ (M = Au, Ag, Cu) have been obtained. The thallium compound [Tl₂(L1)₄]²⁺ has also been prepared by reaction of Tl(PF₆) with L1 and show an interesting structural framework with formation of a metalacycle resembling a macrocyclic compound. For the disubstituted ligand L2 dinuclear complexes such as [Au₂(C ₆F₅)₂(μ-L2)] or [M₂(PPh ₃)₂(μ-L2)](OTf)₂ (M = Au, Ag) or the polymeric species [Ag(μ-L2)]OTf have been isolated. The crystal structures of some of these derivatives show supramolecular assemblies through hydrogen bonding.

Full text of DOI:10.1016/j.jorganchem.2012.05.013

Journal of Organometallic Chemistry 713 (2012) 169e177
Contents lists available at SciVerse ScienceDirect
Journal of Organometallic Chemistry
journal homepage: www.elsevier.com/locate/jorganchem
Heterometallic complexes with the mono and disubstituted [(4-pyridylamino)
carbonyl]ferrocene ligands
*
Carmen Ceamanos, M. Concepción Gimeno , Mathurest N. Jayaswal, Antonio Laguna
Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC-Universidad de Zaragoza, E-50009 Zaragoza, Spain
a r t i c l e i n f o
a b s t r a c t
Article history:
The coordination chemistry of the ferrocene ligands [(4-pyridylamino)carbonyl]ferrocene (L1) and
1,10-bis[(4-pyridylamino)carbonyl]ferrocene (L2) with group 11 metals and thallium has been studied,
and several complexes with coordination of the metal to the pyridine nitrogen atom or to the pyridine
and carbonyl group have been prepared. For the ligand L1 complexes such as [AuX(L1)] (X ¼ Cl, C6F5),
[M(PPh3)(L1)]OTf (M ¼ Au, Ag) (OTf ¼ trifluoromethylsulfonate), [Ag(OTf)(L1)] or [M(L1)2]þ (M ¼ Au, Ag,
Cu) have been obtained. The thallium compound [Tl2(L1)4]2þ has also been prepared by reaction of
Tl(PF6) with L1 and show an interesting structural framework with formation of a metalacycle resem-
Received 30 March 2012
Received in revised form
10 May 2012
Accepted 14 May 2012
Keywords:
Monosubstituted ferrocenyl derivatives
Disubstituted ferrocenyl derivatives
Group 11 compounds
Thallium compounds
Nitrogen ligands
bling
[Au2(C6F5)2(
a
macrocyclic compound. For the disubstituted ligand L2 dinuclear complexes such as
-L2)] or [M2(PPh3)2( -L2)]OTf have
m
m
-L2)](OTf)2 (M ¼ Au, Ag) or the polymeric species [Ag(
m
been isolated. The crystal structures of some of these derivatives show supramolecular assemblies
through hydrogen bonding.
Ó 2012 Elsevier B.V. All rights reserved.
1. Introduction
coordination properties and novel supramolecular structures
[13e25]. These ferrocene-containing amidopyridyl compounds
Ferrocene is a very versatile molecule with important properties
such as high electron density, aromaticity and redox reversibility.
These characteristics, together with the well established routes to
mono and 1,10-disubstituted ferrocene derivatives with a great
variety of organic fragments containing donor atoms such as O, N, S,
P, make ferrocene a very suitable building block in many fields of
research [1e3]. These functionalized ferrocene derivatives and its
metal complexes represent an important topic of research in many
areas that seek special properties of such species, e.g. non-linear
optical properties, charge transport, liquid crystals, electrochemical
recognition, catalysis, nanoparticles, immunoassay reagents or bio-
logical applications [1e12].
Important is also the introduction of a ferrocene group into
supramolecular coordination systems because not only incorpo-
rates a redox-active group but also leads to interesting assembled
structures arising from the conformational flexibility of the ferro-
cene moieties and the varying coordination numbers of metal ions.
Several reports have dealt with the synthesis of ferrocene-based
bidentate ligands that contain pyridine moieties, their interesting
have been used in electrochemical molecular recognition as they
are able to modify selectively their electrochemical properties upon
coordination of the target species [26]. Furthermore ferrocene
receptors for neutral molecules have been developed and been
shown to bind biologically relevant molecules through comple-
mentary hydrogen-binding interactions [27].
Our contributions to this field include several ferrocene ligands
that show interesting coordination properties and in some cases
give rise to supramolecular motifs through weak hydrogen
bonds [28]. We report here on the coordination properties of
[(4-pyridylamino)carbonyl]ferrocene and 1,10-bis[(4-pyridylamino)
carbonyl]ferrocene ligands towards group 11 metals and thallium
compounds. Several zinc, mercury and cadmium complexes have
been reported with these ligands and show third-order non-linear
optical properties [29] and other studies with the 1,10-bis[(3-
pyridylamino)carbonyl]ferrocene species reveal the formation of
metal organometallic frameworks (MOF’s) [30]. Here we describe
the coordination behaviour of these ligands, which are thereby
shown to act as monodentate or bidentate bridging ligands. The
crystal structure determinations provide experimental evidence
for the importance of secondary bonds in the molecular
architecture.
* Corresponding author. Tel.: þ34 976762291; fax: þ34 976761187.
E-mail address: gimeno@unizar.es (M.C. Gimeno).
0022-328X/$ e see front matter Ó 2012 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2012.05.013

170
C. Ceamanos et al. / Journal of Organometallic Chemistry 713 (2012) 169e177
2. Results and discussion
2.1. Synthesis and characterization
The ligands [(4-pyridylamino)carbonyl]ferrocene (L1) and
1,10-bis[(4-pyridylamino)carbonyl]ferrocene (L2) have been
prepared as described previously by reaction of chlorocarbonyl-
ferrocene or 1,10-di(chlorocarbonyl)ferrocene with 4-amino-pyri-
dine in dichloromethane and in the presence of triethylamine [29].
The reactivity of ligand L1 towards several gold, silver or copper
metal complexes has been studied. Thus the reaction of L1 with
[AuX(tht)] in a 1:1 M ratio gives complexes of stoichiometry
[AuX(L1)] (X ¼ Cl (1), C6F5 (2)) (see Scheme 1). The IR spectra for
these complexes show the absorptions arising at the vibrations
Fig. 1. Molecular structure of the cation of complex 3, with the atom labelling scheme;
H atoms are omitted for clarity.
y
(AueCl) at 325 cmꢀ1 in 1 and in 2; the absorptions due to the
1:1 electrolytes in acetone solutions. The IR spectra show, apart
from the absorptions due to the ligand, those arising at the triflate
anion at 1265 (vs, br) [yas(SO3)], 1223 (s) [ys(CF3)], 1150 (vs, br)
presence of pentafluorophenyl rings appear at 1500 (vs), 954 (s)
and 800 (m) cmꢀ1; the v(C]O) and v(C]N) vibrations around 1670
and 1587 cmꢀ1 are also present. The 1H NMR spectra show several
resonances for the different protons in the molecule: a singlet for
the protons of the unsubstituted cyclopentadienyl ring at 4.22 and
[yas(CF3)] and 1023 (s) [ys(SO3)] for complex 3 and similar values are
found for 4. In the 31P{1H} NMR spectra one singlet for 3 and one
multiplet for compound 4 appear. The low temperature spectrum
of 4 presents a broad doublet and thus the coupling of the phos-
phorus with both silver nuclei is not observed (usually appears as
two doublets) and only the doublet is due to the average coupling of
the phosphorus with both silver nuclei. In the mass spectra
(LSIMSþ) the cation molecular peaks appear at m/z ¼ 765 (58%) for
3 and 675 (25%) for 4.
4.29, respectively, two multiplets for the
a and b protons of the
substituted cyclopentadienyl ring at 4.53 and 512 for 1 and 4.57 and
5.04 for 2, two multiplets for the pyridine protons at 8.27 and 8.60
(1), 8.14 and 8.60 (2) and one multiplet for the amine proton at
10.46 and 9.65, respectively. The 19F NMR spectrum of 2 presents
two multiplets for the equivalent ortho and meta fluorine at ꢀ165.0
and ꢀ117.6, respectively, and one triplet at ꢀ163.5 for the para
fluorine with a coupling constant of 20.0 Hz. The LSIMS þ mass
spectra show the molecular peaks at m/z ¼ 539 (7%, 1) and 670
(18%, 2), respectively.
The crystal structure of complex 3 has been established by X-ray
diffraction and the cation is shown in Fig. 1. Selected bond lengths
and angles are collected in Table 1. The gold atom is found in
a linear geometry with an angle slightly distorted from the ideal
value, N(2)eAu(1)eP(11) 175.97(12)ꢁ. The distances Au(1)eN(2)
and Au(1)eP(1) are 2.059(4) and 2.2239(12) Å, respectively,
The reaction of L1 with [M(OTf)(PPh3)] leads to the cationic
complexes [M(PPh3)(L1)]OTf (M ¼ Au (3), Ag (4)). They behave as
CO NH
N
M
PPh3
CO NH
N
Au
X
Fe
Fe
M = Au (3), Ag (4)
X = Cl (1), C6F5 (2)
ii)
i)
+
PPh3
Ag
iii)
CO NH
N
N
CO NH
NH CO
N
Fe
Fe
Fe
iv)
5
v)
+
CO NH
N
NH CO
M
N
CO NH
N
Ag OTf
Fe
Fe
Fe
6
M = Au (7), Ag (8), Cu (9)
Scheme 1. i) [AuCl(tht)] or [Au(C6F5)(tht)], ii) [M(OTf)(PPh3)] (M ¼ Au, Ag), iii) ½ [Ag(OTf)(PPh3)] iv) ½ [Au(tht)2]OTf or ½ Ag(OTf) or ½ [Cu(NCMe)4]PF6, v) Ag(OTf).

C. Ceamanos et al. / Journal of Organometallic Chemistry 713 (2012) 169e177
171
Table 1
planar environment, with slightly distorted angles, the angles being
for one of them N(4)eAg(1)eN(2) 91.8(2), N(4)eAg(1)eP(1)
140.67(18) and N(2)eAg(1)eP(1) 124.81(17)ꢁ. The AgeN distances
for one of the molecules are 2.291(7) and 2.327(7) Å and the AgeP
is 2.365(2), which are similar to those found in three coordinated
silver(I) complexes such as [Ag2{3,5e(CF2)2CF3etriaz}2(PPh3)2]
[31]. There are several intermolecular and intramolecular
secondary contacts that can be classified as hydrogen bonds, the
shortest being between the oxygen atoms of the carbonyl groups
and the protons of the amido groups. Fig. 4 shows the intermo-
lecular contacts 02/H1# of 2.272(10) Å (# ꢀx þ 1, ꢀy þ 1, ꢀz þ 1),
with an angle O2/H1eN1 of 166.60(1)ꢁ.
Selected bond lengths [Å] and angles [ꢁ] for complex 3.
Au(1)eN(2)
Au(1)eP(1)
P(1)eC(41)
P(1)eC(31)
2.059(4)
2.2239(12)
1.807(5)
C(11)eO(1)
C(11)eN(1)
N(1)eC(12)
1.220(6)
1.379(6)
1.383(6)
1.337(6)
1.340(6)
110.78(16)
122.1(4)
126.0(4)
117.8(4)
123.0(3)
119.0(3)
1.809(5)
C(14)eN(2)
P(1)eC(21)
1.810(5)
C(15)eN(2)
N(2)eAu(1)eP(1)
C(41)eP(1)eC(31)
C(41)eP(1)eC(21)
C(31)eP(1)eC(21)
C(41)eP(1)eAu(1)
C(31)eP(1)eAu(1)
175.97(12)
107.1(2)
105.0(2)
105.9(2)
115.20(15)
112.19(16)
C(21)eP(1)eAu(1)
O(1)eC(11)eN(1)
C(11)eN(1)eC(12)
C(14)eN(2)eC(15)
C(14)eN(2)eAu(1)
C(15)eN(2)eAu(1)
The treatment of the L1 with Ag(OTf) in a molar ratio 1:1 affords
[Ag(OTf)(L1)] (6) in a high yield. Complex 6 is a yellow solid,
no-conductor in acetone solutions. The IR spectra show the bands
arising from the triflate anion at 1273 (vs, br) [yas(SO3)], 1222 (s)
which are similar to those found in other complexes with the
coordination NeAueP such as [Au2(PPh3)2{ -Fc(Spy)2}] (2.083(6)
m
and 2.2420(17), respectively) [28 g] or [AuL(PPh3)]OTf (L ¼ 1,10-bis
[((6-methyl)-2-pyridyl)amido]ferrocene) (2.110(5) and 2.2353(17)
Å, respectively) [28i]. There are several intermolecular secondary
contacts that can be classified as hydrogen bonds, the shortest
being between the oxygen atom of the carbonyl group and one of
the phenylic protons O(1)/H(44)# 2.499(4) Å with an angle
C(44)eH(44)/O(1) of 157.7(3)ꢁ (#ꢀx þ 2, ꢀy þ 1, ꢀz þ 1) or
between one oxygen atom of the triflate anion and one proton of
the pyridine moiety, O(3)/H(15)# 2.374(8) Å, C(15)eH(15)/O(3)
149.6(3)ꢁ (# xþ1, y, z). There are also short intramolecular inter-
actions between one of the oxygen atoms of the triflate group and
several protons, e.g. O2/H0 2.006(7) Å and O2/H6 2.465(6) Å.
Fig. 2 shows some of the hydrogen bonds in complex 3.
[
ys(CF3)], 1149 (vs, br) [yas(CF3)] and 1031 (s) [ys(SO3)]. The 1H NMR
spectrum presents the typical resonances for the coordinated
ligand. We propose coordination of the silver centre to the nitrogen
pyridine atom and also to the oxygen of the triflate.
Other group 11 complexes have been obtained by reaction of the
ligand with [Au(tht)2]OTf, AgOTf or [Cu(NCMe)4]PF6 in a 2:1 M ratio,
which affords the complexes [M(L1)2]X (M ¼ Au (7), X ¼ OTf; Ag (8),
X ¼ OTf; Cu (9), X ¼ PF6). Complexes 7e9 are yellow solids and
behave as 1:1 electrolytes in acetone solutions. The three complexes
show similar patterns for the 1H NMR spectra, which correspond to
the resonances of the coordinated ligand. We propose the formation
of linear di-coordinated species with the ligands bonded through
the pyridine nitrogen atoms (see Scheme 1).
The treatment of L1 with the gold(III) compound [Au(C6F5)3(tht)]
gave a product that after crystallization reveals to be the thallium
derivative [Tl2(L1)4][Au(C6F5)4] (10a) (Scheme 2). The formation of
this complex is explained because in the synthesis of the gold(III)
compound a thallium derivative, [Tl(C6F5)2Cl]2, is used and some-
timesthe gold(III) compoundmaycontain somethalliumimpurities.
Once we know the thallium derivative we proceed to a more direct
synthesis by reaction the ligand L1 and Tl(PF6) in a 2:1 M ratio
affording [Tl2(L1)4](PF6)2 (10b).
The reaction of L1 with [Ag(OTf)(PPh3)] in a molar ratio 2:1 leads
to the compound [Ag(PPh3)(FcCONHpy)2]OTf (5) in high yield.
Complex 5 is a yellow solid that behaves as 1:1 electrolyte in
acetone solutions. In the NMR spectrum of complex 5 the reso-
nances are similar to those of compound 4, although now the
integration in the 1H NMR spectrum is for two ferrocenyl ligands.
The 31P{1H} spectrum at low temperature shows two doublets
because of the coupling of the silver centre with the two silver
nuclei.
The crystal structure of complex 5 has been established by X-ray
diffraction studies and the cation is shown in Fig. 3. A selection of
bond lengths and angles are collected in Table 2. The complex
crystallizes with two independent molecules in the asymmetric
unit. The overall bond lengths and angles are very similar within
both molecules. In both the silver center is found in a trigonal
The structure of complex 10a is shown in Fig. 5 and a selection of
bond lengths and angles are collected in Table 3. Complex 10a has
a dinuclear structure with two thallium atoms bridged by two
bidentate N, O ligands; each thallium atoms is further bonded to
another ligand through the pyridine nitrogen atom. In this manner
the central ring is a metalacycle that is reminding of a macrocyclic
ligand. The thallium atoms are three coordinated, but not in
a trigonal planar geometry but in a trigonal pyramid with the
thallium atom occupying the apical position. The pyramidal
geometry implies that the lone pair is stereochemically active and
occupying the vacant site which would therefore complete an
approximately tetrahedral array of electron pairs around the metal.
The TleN distances are 2.676(4) and 2.698(8) Å, which are shorter
than those reported for other thallium complexes and are indica-
tive of strong interaction with the thallium centre. The TleO
distance is 2.628(8) Å. There are only a few structures with the
coordination h
3-N2O around a Tl(I) centre which are [Tl{ONC(CN)
CONMe2}(phen)] with distances TleN of 2.729 and 2.686 Å and
TleO of 2.539 Å [32a], or the complex with the tetrakis(pyrazolyl)
borate containing the 3-(2-diphenylphosphinylphenyl)pyrazole
with distances TleN of 2. 536(3) and 2.587(3) and TleO of 2.541(2)
[32b].
The reactivity of the 1,10-disubstituted ligand L2 has also been
studied towards group 11 metal complexes. Thus, the treatment
with two equivalents of [Au(C6F5)(tht)] in dichloromethane
gives [Au2(C6F5)2(
m-L2)] (11) as a poorly soluble solid (Scheme 3).
Fig. 2. Association of molecules in complex 3 through hydrogen bonds.
The IR spectrum is consistent with the coordination of the

172
C. Ceamanos et al. / Journal of Organometallic Chemistry 713 (2012) 169e177
Fig. 3. Perspective view of the cation of one molecule in complex 5, with the atom labelling scheme; H atoms are omitted for clarity.
pentafluorophenyl-gold(I) fragment with bands at 1510 (s), 957
protons and the singlet of the amine protons. The presence of
equivalent ligands makes us to propose the formation of a dinuclear
complex with bridging ligands, although the low solubility of these
compounds may indicate the presence of polymeric species.
(s) and 806 (m) cmꢀ1; the absorptions due to the ligand at 3422
(y(NH)), 1705 (y(CO)) and 1581 y
(CN) cmꢀ1 are also present. The
1H spectrum shows the resonances characteristic of the ligand
indicating the equivalence of both substituted cyclopentadienyl
rings and also the 19F NMR spectrum agrees with the presence of
equivalent pentafluorophenyl rings. In the mass spectrum the
molecular peak appears at m/z ¼ 1154 (30%) and also the frag-
2.2. Electrochemisty
The electrochemical behaviour of the monosubstituted ligand
[(4-pyridylamino)carbonyl]ferrocene (L1) and some of the gold and
silver complexes have been studied by cyclic voltammetry at
ment arising from the loss of
a pentafluorophenyl ring
[M ꢀ C6F5]þ at m/z ¼ 987 (100%). All the data confirms the
synthesis of a dinuclear derivative with the gold fragments
coordinated to the pyridine nitrogen atoms.
a
platinum electrode in dichloromethane. The free ligand
undergoes a reversible one-electron oxidation process, based on
the ferrocene unit at 0.58 V, which is bit higher than that of the
ferrocene. The coordination of gold and silver to the ligands makes
the redox properties of the complexes markedly different because
the ferrocene redox couple is shifted to higher potentials. The
electron-withdrawing nature of the coordinated metal centres
makes the ferrocene unit harder to oxidize. The coordination of the
neutral fragment Au(C6F5) to L1 produces a small displacement to
higher potential, the oxidation takes place at 0.59 V. However the
coordination of the cationic fragment Ag(PPh3)þ produces a much
higher shift, oxidation at 0.64 V.
Thereaction of2 withtwoequivalents of[M(OTf)(PPh3)] gives the
dinuclear complexes [M2(PPh3)2(m-L2)](OTf)2 (M ¼ Au (12), Ag (13))
with the metal fragments coordinated to the nitrogen atoms prob-
ably in an antiperiplanar conformation of the ferrocene moiety. The
1H NMR spectra show the resonances arising from the coordinated
ligand and also for the phenylic protons. In the 31P{1H} NMR spectra
a singlet appears as a consequence of the equivalent phosphine
ligands. In the mass spectra of complex 12 the molecular peak is not
present but several fragments appear such as [M-OTf] at m/z ¼ 1493
(7%), [M-2OTf]at m/z ¼ 1343 (27%), or [M-2OTf-AuPPh3] at m/z ¼ 885
(32%); for compound 13 only the fragment [M-2OTf-AgPPh3] at m/
z ¼ 797 (11%) appears with enough intensity; other peaks as [M-OTf]
or [M-2OTf] are present but with very low intensity (1%).
3. Experimental
Finally, the reaction of ligand 2 with Ag(OTf) in a 1:1 M ratio have
3.1. Instrumentation
been carried out and affords the complex of stoichiometry [Ag(
L2)]OTf (14). The 1H NMR spectrum show the multiplets due to the
and cyclopentadienyl protons, two multiplets for the pyridine
m-
Infrared spectra were recorded in the range 4000e200 cmꢀ1 on
a PerkineElmer 883 spectrophotometer using Nujol mulls between
a
b

C. Ceamanos et al. / Journal of Organometallic Chemistry 713 (2012) 169e177
173
Fig. 4. Some hydrogen bonds in complex 5.
polyethylene sheets. Conductivities were measured in ca.
5 ꢂ 10ꢀ4 mol dmꢀ3 solutions with a Philips 9509 conductimeter. C,
H, N and S analyses were carried out with a PerkineElmer 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
Bruker ARX 300 and Bruker ARX 400 spectrometers in CDCl3,
otherwise stated. Chemical shifts are cited relative to SiMe4
[Cu(NCMe)4]PF6 [37] were prepared according to published
procedures. [Au(OTf)(PPh3)] was prepared “in situ” from
[AuCl(PPh3)] [33] and AgOTf in dichloromethane. All other reagents
were commercially available.
3.3. Synthesis of [AuX(L1)], X ¼ Cl (1), C6F5 (2)
To a solution of L1 (0.031 g, 0.1 mmol) in dichloromethane
(20 mL) was added [AuCl(tht)] (0.032 g, 0.1 mmol) or
[Au(C6F5)(tht)] (0.045 g, 0.1 mmol) and the mixture was stirred for
30 min. Evaporation of the solvent to ca. 5 mL and addition of
hexane (10 mL) gave complexes 1 or 2 as orange solids. Complex 1:
(1H, external), CFCl3 19F, external) and 85% H3PO4 31P, external).
( (
Cyclic voltammetric experiments were performed by employing an
EG&G PARC Model 273 potentiostat. A three-electrode system was
used, which consists of a platinum disk working electrode, a plat-
inum wire auxiliary electrode, and a saturated calomel reference
electrode. The measurements were carried out in CH2Cl2 solutions
with 0.1 M Bu4NPF6 as a supporting electrolyte. Under the present
experimental conditions, the ferrocenium/ferrocene couple was
located at 0.47 V vs SCE.
Yield 60%, 32 mg L 4 Uꢀ1cm2molꢀ1. C16H14AuClFeN2O (537.980):
M
calcd. C 35.69, H 2.62, N 5.20; found C 35.52, H 2.50, N 4.99. NMR,
1H,
d: 4.22 (s, 5H, C5H5), 4.53 (m, 2H, C5H4), 5.12 (m, 2H, C5H4), 8.27
(m, 2H, py), 8.60 (m, 2H, py), 10.46 (m, br, 1H, NH). Complex 2: Yield
68%, 45 mg, LM 6 Uꢀ1cm2molꢀ1. C22H14AuF5FeN2O (670.004): calcd.
C 39.40, H 2.10, N 4.18; found C 39.12, H 2.22, N 4.31. NMR (CD3)2CO,
1H,
d
: 4.29 (s, 5H, C5H5), 4.57 (m, 2H, C5H4), 5.04 (m, 2H, C5H4), 8.14
3.2. Starting materials
(m, 2H, py), 8.60 (m, 2H, py), 9.65 (m, br, 1H, NH).19F,
d
: ꢀ117.6 (m,
2F, m-F), ꢀ163.2 (t, 1F, p-F, J(FF) 20.0 Hz), ꢀ165.0 (m, 2F, o-F).
The starting materials L1 and L2 [29], [AuCl(tht)] [33],
[Au(C6F5)(tht)] [34], [Au(tht)2]OTf [35], [Ag(OTf)(PPh3)] [36],
3.4. Synthesis of [M(PPh3)(L1)]OTf, M ¼ Au (3), Ag (4)
Table 2
Selected bond lengths [Å] and angles [ꢁ] for complex 5.
To a solution of L1 (0.031 g, 0.1 mmol) in dichloromethane
(20 mL) was added [Au(OTf)(PPh3)] (0.061 g, 0.1 mmol) or
[Ag(OTf)(PPh3)] (0.052 g, 0.1 mmol) and the mixture was stirred for
30 min. Evaporation of the solvent to ca. 5 mL and addition of
hexane (10 mL) gave complexes 3 or 4 as orange solids. Complex 3:
Ag(1)eN(4)
Ag(1)eN(2)
Ag(1)eP(1)
N(4)eAg(1)eN(2)
N(4)eAg(1)eP(1)
N(2)eAg(1)eP(1)
2.291(7)
2.327(7)
Ag(2)eN(8)
Ag(2)eN(6)
2.251(7)
2.319(7)
2.358(2)
93.6(2)
139.40(19)
122.15(19)
2.365(2)
Ag(2)eP(2)
91.8(2)
140.67(18)
124.81(17)
N(8)eAg(2)eN(6)
N(8)eAg(2)eP(2)
N(6)eAg(2)eP(2)
Yield 72%, 68 mg L 99 Uꢀ1cm2molꢀ1. C35H29AuF3FeN2O4PS
M
(914.055): calcd. C 45.95, H 3.19, N 3.06, S 3.49; found C 46.20, H

174
C. Ceamanos et al. / Journal of Organometallic Chemistry 713 (2012) 169e177
Fig. 5. Molecular structure of the cation of complex 10a, with the atom labelling scheme; H atoms are omitted for clarity.
3.45, N 2.79, S 3.27. NMR: 1H,
C5H4), 4.83 (m, 2H, C5H4), 7.42e7.56 (m, 15H, Ph), 7.60 (m, 2H, py),
d
: 4.26 (s, 5H, C5H5), 4.47 (m, 2H,
{1H}, ꢀ85 ꢁC,
d
: 15.7 (2d, 1P, PPh3, J(109AgP) 750.7, J(107AgP)
654.6 Hz).
7.68 (m, br, 1H, NH), 8.50 (m, 2H, py). P{1H},
d
: 33.3 (s, 1P, PPh3).
31
Complex 4: Yield 85%, 69 mg L 110 Uꢀ1cm2molꢀ1. C35H29AgF3
M
-
3.6. Synthesis of [Ag(OTf)(L1)] (6)
FeN2O4PS (823.993): calcd. C 50.97, H 3.54, N 3.40, S 3.88; found C
50.74, H 3.22, N 3.34, S 3.67. NMR: 1H,
d
: 4.23 (s, 5H, C5H5), 4.42 (m,
To a solution of L1 (0.031 g, 0.1 mmol) in dichloromethane
(20 mL) was added AgOTf (0.026 g, 0.1 mmol) and the mixture was
stirred for 30 min. Evaporation of the solvent to ca. 5 mL and
addition of hexane (10 mL) gave complex 6 as an orange solid. Yield
2H, C5H4), 5.02 (m, 2H, C5H4), 7.37e7.53 (m, 15H, Ph), 7.92 (m, 2H,
py), 8.25 (m, 2H, py), 8.88 (m, br,1H, NH). 31P{1H}, ꢀ55 ꢁC,
1P, PPh3), J(AgP)ave 511.2 Hz.
d: 9.63 (d,
69%, 39 mg L 9 Uꢀ1cm2molꢀ1. C17H14AgF3FeN2O4S (561.902):
M
calcd. C 36.30, H 2.51, N 4.98, S 5.69; found C 36.55, H 2.89, N 5.12, S
3.5. Synthesis of [Ag(PPh3)(L1)2]OTf (5)
5.86. NMR: 1H (dmso-d6),
d: 4.26 (s, 5H, C5H5), 4.37 (m, 2H, C5H4),
4.48 (m, 2H, C5H4), 7.61 (m, 4H, py), 8.52 (m, br, 1H, NH).
To a solution of L1 (0.062 g, 0.2 mmol) in dichloromethane
(20 mL) was added [Ag(OTf)(PPh3)] (0.052 g, 0.1 mmol) and the
mixture was stirred for 30 min. Evaporation of the solvent to ca.
5 mL and addition of hexane (10 ml) gave complex 5 as an orange
3.7. Synthesis of [M(L1)2]X (M ¼ Au (7), X ¼ OTf; Ag (8), X ¼ OTf;
Cu(9), X ¼ PF6)
solid. Complex 5: Yield 85%, 78 mg
C51H43AgF3Fe2N4O5PS (1130.039): calcd. C 54.15, H 3.83, N 4.95, S
2.83; found C 54.35, H 3.69, N 5.22, S 3.16. NMR: 1H,
: 4.23 (s, 10H,
L
102 U .
ꢀ1cm2molꢀ1
M
To a solution of L1 (0.062 g, 0.2 mmol) in dichloromethane
(20 mL) was added [Au(tht)2]OTf (0.052 g, 0.1 mmol) or AgOTf
(0.026 g, 0.1 mmol) or [Cu(NCMe)4]PF6 (0.038 g, 0.1 mmol) and the
mixture was stirred for 30 min. Evaporation of the solvent to ca.
d
C5H5), 4.43 (m, 4H, C5H4), 5.02 (m, 4H, C5H4), 7.42e7.50 (m, 15H,
Ph), 7.92 (m, 4H, py), 8.25 (m, 4H, py), 8.89 (m, br, 1H, NH). 31P
X
Fe
Tl
CONH
N
O
C
Fe
NH
N
i)
N
HN
CO NH
N
Tl
C
O
Fe
ii)
NHCO
N
Fe
Fe
X = [Au(C6F5)4]- (10a), PF6 (10b)
Scheme 2. i) [Au(C6F5)3(tht)], ii) Tl(PF6).

C. Ceamanos et al. / Journal of Organometallic Chemistry 713 (2012) 169e177
175
Table 3
addition of hexane (10 mL) gave complex 10b as orange solids. Yield
68%, 60 mg 202 C64H56F12Fe4N8O4P2Tl2
ꢀ1cm2molꢀ1
(1924.059): calcd. C 39.91, H 2.93, N 5.82; found C 40.23, H 3.10, N
5.95. NMR: 1H,
: 4.29 (s, 20H, C5H5), 4.49 (m, 8H, C5H4), 4.79 (m,
Selected bond lengths [Å] and angles [ꢁ] for complex 10a.
L
U
.
M
Au(1)eC(19)
Au(1)eC(7)
Au(1)eC(1)
Au(1)eC(13)
C(19)eAu(1)eC(13)
C(19)eAu(1)eC(1)
C(13)eAu(1)eC(1)
C(19)eAu(1)eC(7)
C(13)eAu(1)eC(7)
2.049(9)
2.060(10)
2.058(9)
2.056(10)
91.6(3)
Tl(1)eO(2)
Tl(1)eN(64)
2.628(8)
2.676(4)
2.698(8)
1.219(11)
89.7(3)
79.9(2)
86.1(2)
76.81(12)
d
Tl(1)eN(74)#1
C(25)eO(1)
C(1)eAu(1)eC(7)
O(2)eTl(1)eN(64)
O(2)eTl(1)eN(74)#1
N(64)eTl(1)eN(74)#1
8H, C5H4), 7.43 (m, br, 4H, NH), 7.55 (m, 8H, py), 8.53 (m, 4H, py).
90.8(3)
3.9. Synthesis of [Au2(C6F5)2(L2)] (11)
177.1(3)
178.9(4)
87.9(3)
To a solution of L2 (0.043 g, 0.1 mmol) in dichloromethane
(20 mL) was added [Au(C6F5)(tht)] (0.090 g, 0.2 mmol) and the
mixture was stirred for 30 min. Evaporation of the solvent to ca.
5 mL and addition of hexane (10 mL) afforded complex 11 as an
orange solid. Yield 62%, 72 mg L 5 Uꢀ1cm2molꢀ1. C34H18Au2F10
Symmetry transformations used to generate equivalent atoms: #1 ꢀx,ꢀy þ 2,ꢀz þ 1.
5 mL and addition of hexane (10 mL) gave complexes 7, 8 or 9 as
M
-
orange solids. Complex 7: Yield 69%, 58 mg L 101 Uꢀ1cm2molꢀ1
.
FeN4 (1122.005): C 36.36, H 1.61, N 4.99; found C 36.21, H 1.50, N
4.67. NMR, 1H,
: 4.61 (m, 4H, -C5H4), 5.16 (m, 4H, -C5H4), 8.25 (m,
2H, py), 8.62 (m, 2H, py), 10.09 (m, br, 1H, NH). 19F,
: ꢀ111.9 (m, 4F,
m-F), ꢀ159.3 (t, 2F, p-F, J(FF) 19.6 Hz), ꢀ161.5 (M, 4F, o-F).
M
d
a
b
C33H28AuF3Fe2N4O5S (958.009): calcd. C 41.33, H 2.94, N 5.84, S
3.33; found C 41.53, H 3.19, N 5.95, S, 3.55. NMR: 1H (dmso-d6),
d:
d
4.22 (s, 5H, C5H5), 4.50 (m, 2H, C5H4), 5.04 (m, 2H, C5H4), 7.91 (m,
4H, py), 8.50 (m, 4H, py), 9.9 (m, br, 1H, NH). Complex 8: Yield 78%,
56 mg L 105 Uꢀ1cm2molꢀ1. C33H28AgF3Fe2N4O5S (867.948): C
M
3.10. Synthesis of [M2(PPh3)2(m-L2)](OTf)2, M ¼ Au (12), Ag (13)
45.62, H 3.25, N 6.45, S 3.68; found C 45.86, H 3.29, N 6.60, S 3.64.
NMR: 1H,
d: 4.70 (s, 10H, C5H5), 5.14 (m, 4H, C5H4), 5.69 (m, 4H,
To a solution of L2 (0.043 g, 0.1 mmol) in dichloromethane
(20 mL) was added [Au(OTf)(PPh3)] (0.122 g, 0.2 mmol) or
[Ag(OTf)(PPh3)] (0.104 g, 0.2 mmol) and the mixture was stirred for
30 min. Evaporation of the solvent to ca. 5 mL and addition of
hexane (10 mL) gave complexes 12 or 13 as orange solids. Complex
C5H4), 7.64 (m, 4H, py), 8.28 (m, 4H, py), 9.85 (m, br, 2H, NH).
Complex 9: yield 73%. 44 mg L 98 Uꢀ1cm2molꢀ1. C32H28CuF6
M
-
Fe2N4O2P (819.984): C 46.83, H 3.44, N 6.83; found C 46.86, H 3.29,
N 6.90. NMR: 1H (dmso-d6),
d: 4.19 (s, 10H, C5H5), 4.52 (m, 4H,
C5H4), 5.04 (m, 4H, C5H4), 7.86 (m, 4H, py), 8.48 (m, 4H, py), 9.93 (m,
br, 2H, NH).
12: Yield 81%, 163 mg L 175 Uꢀ1cm2molꢀ1. C60H48Au2F6Fe-
M
N4O8P2S2 (1642.097): calcd. C 43.84, H 2.94, N 3.41, S 3.89, found: C
43.86, H 3.19, N 3.50, S 3.64. NMR: 1H,
d
: 4.48 (m, 4H, C5H4), 4.98 (m,
4H, C5H4), 7.52e7.56 (m, 30H, Ph), 7.83 (m, 2H, py), 8.35 (m, 2H, py),
9.44 (m, br, 1H, NH). 31P{1H},
: 30.6 (s, 2P, PPh3). Complex 13: Yield
78%, 143 mg 190 C60H48Ag2F6FeN4O8P2S2
ꢀ1cm2molꢀ1
(1461.974): calcd. C 49.25, H 3.31, N 3.83, S 4.37, found: C 49.56, H
3.8. Synthesis of [Tl2(L1)4](PF6)2 (10b)
d
To a solution of L1 (0.031 g, 0.1 mmol) in dichloromethane
(20 mL) was added Tl(PF6) (0.017 g, 0.05 mmol) and the mixture
was stirred for 30 min. Evaporation of the solvent to ca. 5 mL and
L
M
U
.
3.29, N 3.61, S 4.34. NMR: 1H,
d: 4.47 (m, 2H, C5H4), 5.21 (m, 4H,
CO NH
N
Au C6F5
Fe
CO NH
N
Au C6F5
11
i)
2+
CO NH
N M
PPh3
CO NH
N
ii)
Fe
Fe
M
CO NH
N
PPh3
CO NH
N
M = Au (12), Ag (13)
iii)
2+
Ag
CO NH
N
N
NH CO
Fe
Fe
CO NH
N
Ag
N
NH CO
14
Scheme 3. i) 2 [Au(C6F5)(tht)], ii) 2 [M(OTf)(PPh3)] (M ¼ Au, Ag), iii) ½ [Au(tht)2]OTf or ½ Ag(OTf) or ½ [Cu(NCMe)4]PF6.

176
C. Ceamanos et al. / Journal of Organometallic Chemistry 713 (2012) 169e177
Table 4
X-ray data for complexes 3, 5, and 10a.
Compound
3
5
10a
Formula
Mr
C35H29AuF3FeN2O4PS
914.45
C52H45AgCl2F3Fe2N4O5PS
1216.42
C59H32AuCl6F20Fe2N4O2Tl
1934.62
Habit
yellow prism
0.40 ꢂ 0.40 ꢂ 0.30
Triclinic
yellow prism
0.10 ꢂ 0.08 ꢂ 0.08
Triclinic
yellow plate
Crystal size (mm)
Crystal system
Space group
Cell constants:
a (Å)
0.28 ꢂ 0.20 ꢂ 0.08
Monoclinic
P-1
P-1
P2(1)/c
10.4122(5)
10.9684(6)
14.9925(8)
92.0790(10)
91.3120(10)
107.5390(10)
1630.52(15)
2
16.3807(8)
14.4622(8)
22.3140(12)
90.128(4)
110.684(5)
116.158(5)
4962.6(4)
4
18.717(2)
17.9923(19)
19.349(2)
90
107.787(2)
90
6204.7(11)
4
2.071
b (Å)
c (Å)
a
b
g
(ꢁ)
(ꢁ)
(ꢁ)
V (Å3)
Z
Dx (Mg mꢀ3
)
1.863
5.112
1.628
1.214
m
(mmꢀ1
)
5.771
F(000)
896
2464
3696
T (ꢁC)
ꢀ173
ꢀ173
ꢀ173
2
qmax
51
50
50
No. of refl.:
measured
17073
6053
0.2343e0.3092
0.019
446
67714
17420
0.8882e0.9091
0.12
1295
212
0.182
0.099
1.217
1.15
33019
10898
0.2949e0.6553
0.051
772
219
0.152
0.055
1.040
5.12
independent
Transmissions
Rint
Parameters
Restraints
0
wR(F2, alle Refl.)
0.084
0.032
1.058
2.58
R(I, >2
s
(I))
S
max. Dr (e Åꢀ3
)
C5H4), 7.20e7.42 (m, 30H, Ph), 7.86 (m, 4H, py), 9.36 (m, br, 1H, NH).
Appendix A. Supplementary material
31P{1H}, 10.2 (s, br, 2P, PPh3).
CCDC-863384 (3), 863385 (5) and 863385 (10a) contain the
supplementary crystallographic data for this paper. These data can
be obtained free of charge from The Cambridge Crystallographic
Data Centre via www.ccdc.cam.ac.uk/data_request/cif.
3.11. Synthesis of [Ag2(m-L2)2](OTf)2 (14)
To a solution of L2 (0.043 g, 0.1 mmol) in dichloromethane
(20 mL) was added AgOTf (0.026 g, 0.1 mmol) and the mixture was
stirred for 30 min. After a few minutes a precipitate appears which
was filtered off to give an orange solid of complex 14. Yield 77%,
References
[1] (a) A. Togni, T. Hayashi (Eds.), Ferrocenes, Homogeneous Catalysis, Organic
Synthesis and Materials Science, VCH, Weinheim, 1995;
53 mg L 192 Uꢀ1cm2molꢀ1. C46H36Ag2F6Fe2N8O10S2 (1363.870):
M
(b) A. Togni, R.L. Halterman (Eds.), Metallocenes, VCH, Weinheim, 1998;
(c) N.J. Long, Metallocenes, an Introduction to Sandwich Complexes, Blackwell
Science, Oxford, 1998;
calcd. C 40.47, H 2.66, N 8.21, S 4.69, found: C 40.59, H 2.56, N 8.01, S
4.51. NMR: 1H,
d: 4.27 (m, 8H, C5H4), 4.79 (m, 8H, C5H4), 7.60 (m, 8H,
ꢀ
ꢀ
ꢀ
(d) P. Stepnicka (Ed.), Ferrocene, Ligands, Materials and Biomolecules, John
Wiley & Sons, Ltd, Chichester, 2008.
py), 7.55 (m, 8H, py), 8.52 (m, br, 4H, NH).
[2] (a) N.J. Long, Angew. Chem. Int. Ed. 34 (1995) 21e38;
(b) I. Manners, Adv. Organomet. Chem. 37 (1995) 131e168;
(c) I. Manners, Chem. Commun. (1999) 857e865.
3.12. Crystallography
ꢀ
ꢀ
ꢀ
[3] (a) U. Siemeling, T. Klemann, C. Bruhn, J. Schulz, P. Stepnicka, Dalton Trans.
40 (2011) 4722e4740;
(b) P. Stepnicka, J. Schulz, T. Klemann, U. Siemeling, I. Cĭsarovǎ, Organome-
tallics 29 (2010) 3187e3200.
ꢀ
ꢀ
ꢀ
ꢀ
Crystal Structure Determinations: Data were registered on
a Bruker SMART APEX CCD (3 and 10a) and a Xcalibur Oxford
[4] Y. Zhu, Y. Clot, M.O. Wolf, G.P.A. Yap, J. Am. Chem. Soc. 120 (1998) 1812e1821.
[5] (a) P.D. Beer, Acc. Chem. Res. 31 (1998) 71e80;
(b) P.D. Beer, P.A. Gale, G.Z. Chen, J. Chem. Soc. Dalton Trans. (1999)
1897e1909.
[6] R.V. Honeychuck, M.O. Okoroafor, L.H. Shen, C.H. Brubaker Jr., Organometallics
5 (1986) 482e490.
Diffraction (5) diffractometers. Data collection type:
u-scans.
Absorption corrections were based on multiple scans with the
program SADABS [38]. The structures were refined on F2 using the
program SHELXL-97 [39]. All non-hydrogen atoms were refined
anisotropically. Further crystallographic data is collected is Table 4.
[7] (a) A.C. Templeton, W.P. Wuelfing, R.W. Murray, Acc. Chem. Res. 33 (2000)
27e36;
(b) R.S. Ingram, M.J. Hostetler, R.W. Murray, J. Am. Chem. Soc. 119 (1997)
9175e9178.
[8] I. Willner, E. Katz, Angew. Chem. Int. Ed. Engl. 39 (2000) 1180e1218.
[9] A. Tarraga, P. Molina, J.L. López, M.D. Velasco, D. Bautista, Organometallics 21
(2002) 2055e2065.
Acknowledgements
[10] C.E. Immoos, S.J. Lee, M.W. Grinstaff, J. Am. Chem. Soc. 126 (2004)
10814e10815.
[11] R.H. Fisher, G. Jaouen, Organometallics 22 (2003) 2166e2177.
[12] (a) D.R.V. Staveren, N. Metzler-Nolte, Chem. Rev. 104 (2004) 5931e5985;
(b) M. Patra, G. Gasser, M. Wenzel, K. Merz, J.E. Bandow, N. Metzler-Nolte,
We thank the Ministerio de Economía y Competitividad-FEDER
(CTQ2010-20500-C02-01), the Departamento de Ciencia, Tecnolo-
gía y Universidad del Gobierno de Aragon (E77) and the Fondo
Social Europeo for finantial support.

C. Ceamanos et al. / Journal of Organometallic Chemistry 713 (2012) 169e177
177
Organometallics 29 (2010) 4312e4319;
(c) S. Martic, M. Labib, P.O. Shipman, H.B. Kraatz, Dalton Trans. 40 (2011)
H. Stoeckli-Evans, S.M. Strawbridge, J.H.R. Tucker, Dalton Trans. (2004)
2831e2832;
ꢁ
7264e7290.
(d) J. Westwood, S.J. Coles, S.R. Collinson, G. Gasser, S.J. Green,
M.B. Hursthouse, M.E. Light, J.H.R. Tucker, Organometallics 23 (2004)
946e951.
[13] R. Horikoshi, T. Mochida, H. Moriyama, Inorg. Chem. 41 (2002) 3017e3024.
[14] H. Hou, L. Li, Y. Zhu, Y. Fan, Y. Qiao, Inorg. Chem. 43 (2004) 4767e4774.
[15] C. Fang, C. Duan, D. Guo, C. He, Q. Meng, Z. Wang, C. Yan, Chem. Commun.
(2001) 2540e2541.
[16] E. Lindner, R. Zong, K. Eichele, U. Weisser, M. Ströbele, Eur. J. Inorg. Chem.
(2003) 705e712.
[28] (a) M.J. Calhorda, P.J. Costa, P.N. Martinho, M.C. Gimeno, A. Laguna, S. Quintal,
M.D. Villacampa, J. Organomet. Chem. 691 (2006) 4181e4188.(b) J.E. Aguado,
S. Canales, M.C. Gimeno, P.G. Jones, A. Laguna, M.D. Villacampa, Dalton Trans.
(2005) 3005e3015;
[17] (a) A. Ion, J.C. Moutet, E. Saint-Aman, G. Royal, S. Tingry, J. Pecaut, S. Menage,
R. Ziessel, Inorg. Chem. 40 (2001) 3632e3636 M. Buda, J. C. Moutet, E.
Saint-Aman, A. D. Cian, J. Fischer, R. Ziessel, Inorg. Chem. 37(1998)
4146e4148.
[18] J. Kühnert, M. Dusek, J. Demel, H. Lang, P. Stepnicka, Dalton Trans. (2007)
2802e2811.
(c) J.E. Aguado, M.J. Calhorda, M.C. Gimeno, A. Laguna, Chem. Commun. (2005)
3355e3356;
(d) E.M. Barranco, O. Crespo, M.C. Gimeno, P.G. Jones, A. Laguna, Eur. J. Inorg.
Chem. (2004) 4820e4827;
(e) J.E. Aguado, M.J. Calhorda, P.J. Costa, O. Crespo, V. Félix, M.C. Gimeno,
P.G. Jones, A. Laguna, Eur. J. Inorg. Chem. (2004) 3038e3047;
(f) S. Canales, O. Crespo, A. Fortea, M.C. Gimeno, P.G. Jones, A. Laguna, J. Chem.
Soc. Dalton Trans. (2002) 2250e2255;
ꢀ
ꢀ
ꢀ
ꢀ
[19] C. Fang, C. Duan, H. Mo, C. He, Q. Meng, Y. Liu, Y. Mei, Z. Wang, Organome-
tallics 20 (2001) 2525e2532.
[20] K. Tani, T. Mihana, T. Yamagata, T. Saito, Chem. Lett. (1991) 2047e2050.
[21] B. Neumann, U. Siemeling, H.G. Stammler, U. Vorfeld, J.G.P. Delis,
P.E.N.M. Leeuwen, K. Vrieze, J. Fraanje, K. Goubitz, F.F. Biani, P. Zanello,
J. Chem. Soc. Dalton Trans. (1997) 4705e4711.
(g) E.M. Barranco, O. Crespo, A. Fortea, M.C. Gimeno, P.G. Jones, A. Laguna,
J. Chem. Soc. Dalton Trans. (2001) 2523e2529;
(h) J.E. Aguado, O. Crespo, M.C. Gimeno, P.G. Jones, A. Laguna, Y. Nieto, Eur. J.
Inorg. Chem. (2008) 3031e3039;
[22] D.L. Reger, K.J. Brown, J.R. Gardinier, M.D. Smith, J. Organomet. Chem. 690(2005)
1889e1900.
(i) J.E. Aguado, O. Crespo, M.C. Gimeno, P.G. Jones, A. Laguna, M.D. Villacampa,
Dalton Trans. 39 (2010) 4321e4330.
[23] A.H. Ilkhechi, M. Bolte, H.W. Lerner, M.J.Wagner, J. Organomet. Chem. 690(2005)
1971e1977.
[29] G. Li, Y. Song, H. Hou, L. Li, Y. Fan, Y. Zhu, X. Meng, L. Mi, Inorg. Chem. 42 (2003)
913e920.
[24] J.D. Carr, S.J. Coles, M.B.;M.B. Hursthouse, M.E. Light, E.L. Munro, J.H.R. Tucker,
J. Westwood, Organometallics 19 (2000) 3312e3315.
[25] D. Braga, M. Polito, M. Bracaccini, D. D’Addario, E. Tagliavini, D.M. Proserpio,
F. Crepioni, Chem. Commun. (2002) 1080e1081 n) D. Braga, M. Polito, D.
D’Addario, E. Tagliavini, D. M. Proserpio, F. Crepioni, J. W. Sted, Organome-
tallics 22(2003) 4532e4538.
[30] K. Wei, J. Ni, Y. Liu, Inorg. Chem. 49 (2010) 1834e1848.
[31] H.V.R. Dias, S. Singh, C.F. Campana, Inorg. Chem. 47 (2008) 3943e3945.
[32] (a) V.V. Skopenko, V.V. Ponomareva, K.V. Domasevich, J. Sieler, R. Kempe,
E.B. Rusanov, Russ. J. Gen. Chem. 67 (1997) 835e844;
(b) S. Kealey, N.J. Long, A.J.P. White, A.D. Gee, Dalton Trans. (2007)
4763e4765.
[26] (a) P.D. Beer, J. Cadman, Coord. Chem. Rev. 205 (2000) 131e155;
(b) H. Plenio, C. Aberle, Chem. Eur. J. 7 (2001) 4438e4446;
(c) X. Cui, H.M. Carupaça, R. Delagado, M.G.D. Drew, V. Félix, Dalton Trans.
(2004) 1743e1751;
[33] R. Usón, A. Laguna, Inorg. Synth. 21 (1982) 71e74.
[34] R. Usón, A. Laguna, M. Laguna, Inorg. Synth. 26 (1989) 85e91.
[35] R. Usón, A. Laguna, A. Navarro, R.V. Parish, L.S. Moore, Inorg. Chim. Acta 112
(1986) 205e208.
(d) G. Denault, P.A. Gale, M.B. Hursthouse, M.E. Light, C.N. Warriner, New J.
Chem. 26 (2002) 811e813.
[36] M. Bardají, O. Crespo, A. Laguna, A.K. Fischer, Inorg. Chim. Acta 304 (2000)
7e16.
[27] (a) J.D. Carr, S.J. Coles, M.B. Hursthouse, M.E. Light, J.R. Tucker, J. Westwood,
Angew. Chem. Int. Ed. Engl. 39 (2000) 3296e3299;
[37] G.J. Kubas, Inorg. Synth. 19 (1979) 90e92.
[38] G.M. Sheldrick, SADABS, Program for Absorption Correction, University of
Göttingen, Göttingen, Germany, 1996.
[39] G.M. Sheldrick, SHELXL-97, Program for Crystal Structure Refinement,
University of Göttingen, Göttingen, Germany, 1997.
(b) S.R. Collinson, T. Gelbrich, M.B. Hursthouse, J.H.R. Tucker, Chem. Commun.
(2001) 555e556;
ꢀ
(c) H. Miyaji, M. Dudic, G. Gasser, S.J. Green, N. Moran, I. Prokes, G. Labat,