Synthesis and structural characterization of tridentate [C,N,S] thiosemicarbazone palladacycles. Crystal and molecular structures of [Pd{3-FC6H3C(Me)NNC(S)NHMe}]4, [Pd{4-FC 6H3C(Me)NNC(S)NHEt}]4<

Article abstract of DOI:10.1016/j.poly.2011.09.012

Reaction of the thiosemicarbazones 3-FC₆H₄C(Me)NN(H) C(S)NHME a, 4-FC₆H₄C(Me)NN(H)C(S)NHEt b, and 2-BrC ₆H₄C(Me)NN(H)C(S)NHPh c, with potassium tetrachloropalladate(II) in ethanol, lithium

Full text of DOI:10.1016/j.poly.2011.09.012

Polyhedron 31 (2012) 217–226
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Polyhedron
journal homepage: www.elsevier.com/locate/poly
Synthesis and structural characterization of tridentate [C,N,S] thiosemicarbazone
palladacycles. Crystal and molecular structures of [Pd{3-FC6H3C(Me)@NN@C(S)
NHMe}]4, [Pd{4-FC6H3C(Me)@NN@C(S)NHEt}]4 and [(Pd{2-BrC6H3C(Me)@NN@C(S)
NHPh})2(l-Ph2P(CH2)2PPh2)]
Javier Martínez a, M. Teresa Pereira a, Juan M. Ortigueira a, Brais Bermúdez a, José M. Antelo a,
Alberto Fernández b, José M. Vila a,
⇑
a Departamento de Química Inorgánica, Universidad de Santiago de Compostela, E-15782 Santiago de Compostela, Spain
b Departamento de Química Fundamental, Universidade da Coruña, E-15071 La Coruña, Spain
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 29 May 2011
Accepted 11 September 2011
Available online 21 September 2011
Reaction of the thiosemicarbazones 3-FC6H4C(Me)@NN(H)C(@S)NHME a, 4-FC6H4C(Me)@NN(H)C(@S)N-
HEt b, and 2-BrC6H4C(Me)@NN(H)C(@S)NHPh c, with potassium tetrachloropalladate(II) in ethanol, lith-
ium tetrachloropalladate(II) in methanol or palladium(II) acetate in acetic acid gave the tetranuclear
cyclometallated complexes [Pd{3-FC6H3C(Me)@NN@C(S)NHMe}]4 1a, [Pd{4-FC6H3C(Me)@NN@C-
(S)NHEt}]4 1b, and [Pd{2-BrC6H3C(Me)@NN@C(S)NHPh}]4 1c. Reaction of 1a–c with the diphosphines
Ph2P(CH2)nPPh2 dppm (n = 1), dppe (n = 2), dppp (n = 3), dppb (n = 4) or Ph2PCH@CHPPh2 trans-dppe, in a
Keywords:
Cyclometallation
Thiosemicarbazones
Palladium
1:2 molar ratio gave the dinuclear phosphine-bridged complexes [(Pd{XC6H3C(Me)@NN@C(S)NHR})2(
l-
Ph2P(CH2)nPPh2)] 2a–c, 3a–c, 4a–c, 5a–c (n = 1–4) and [(Pd{XC6H3C(Me)@NN@C(S)NHR})2( -Ph2PCH@
l
CH-PPh2)] 6a–c. Treatment of 1a–c with PPh2CH2PPh2, dppm, in a 1:4 molar ratio gave the mononuclear
cyclometallated complexes [Pd{XC6H3C(Me)@NN@C(S)NHR}-(Ph2PCH2PPh2-P)] 7a–c; however, the
diphosphines with n P 2 failed to give the analogous reaction. The molecular structures of 1a, 1b and 3c
have been determined by X-ray diffraction analysis and the intra- and intermolecular interactions are
discussed.
Diphosphines
Crystal structure
Ó 2011 Elsevier Ltd. All rights reserved.
1. Introduction
with the nucleophile, whereas thiosemicarbazones remain firmly
bonded to the metal in a tridentate manner even upon treatment
Cyclometallated complexes are well documented for a great
variety of metal centers and ligands. They have been successfully
used in organic synthesis [1–4], photochemistry [5], optical resolu-
tion processes [6,7], catalysis [8] and are rather promising as po-
tential biologically active materials [9] and liquid crystals [10];
owing to their variety they may be classified according to the
metal, to the donor atom, or to chelate ring size. By far the best-
studied examples are the five-membered palladacycles with nitro-
gen donor atoms [11].
Thiosemicarbazones coordinate the metal ion as monoanionic
or bianionic tridentate [C,N,S] donor ligands, and we have previ-
ously shown that the related semicarbazones may also behave as
terdentate [C,N,O] ligands; however, in the ensuing palladacycles
the metal–oxygen bond is readily cleaved upon reaction with
nucleophiles such as tertiary phosphines. The [C,N,O] coordination
stands only if a vacant site on the metal is created prior to reaction
with strong chelating ligands. The number of donor atoms on the
ligands depends on the starting aldehyde or ketone, and given
the tautomerism typical of thiosemicarbazone [12,13], the most
common coordination modes usually involve the sulfur atom in
the thiolate form [12–17]; also, [C,N,O] and [C,N,S], as well as
[C,N,N], tridentate ligands give rise to complexes with fused rings
at the metal center [18–23].
Herein we describe the synthesis and characterization of novel
cyclometallated complexes derived from halogenated thiosemicarba-
zones, which react with tertiary diphosphines to give new dinuclear
and mononuclear compounds, where either two or one of the phos-
phorus atoms are bonded to palladium centers, respectively. The crys-
tal structure analysis shows that they display self-organization
consequent on the differing hydrogen bonds present in the complexes.
2. Results and discussion
⇑
Thiosemicarbazones a–c were prepared by reaction of 4-methyl,
Corresponding author. Tel.: +34 9 8152800; fax: +34 9 81595012.
E-mail addresses: josemanuel.vila@usc.es, qideport@usc.es (J.M. Vila).
4-ethyl or 4-phenyl-3-thiosemicarbazide with 30-fluoro, 40-fluoro
0277-5387/$ - see front matter Ó 2011 Elsevier Ltd. All rights reserved.
doi:10.1016/j.poly.2011.09.012

218
J. Martínez et al. / Polyhedron 31 (2012) 217–226
or 2’-bromoacetophenone, as appropriate, which were fully charac-
terized (see Section 3). The most prominent features were the char-
by the crystal structure resolution of complexes 1a and 1b (vide in-
fra). The m(C@N) band was shifted to lower wavenumbers upon
acteristic
assigned to the NHR and NH groups, respectively; distinctive
(C@N) and (C@S) stretches appeared in the ranges 1603–1594
m
(N–H) bands in the IR spectra ca. 3300 and 3200 cmꢀ1
,
complex formation by ca. 40 cmꢀ1 [24] in agreement with coordi-
nation of the palladium atom to the C@N moiety through the nitro-
gen lone pair [25,26].
m
m
and 833–799 cmꢀ1, also respectively. The NH and NHR proton res-
onances in the 1H NMR spectra appeared ca. d 8.63 (a), d 8.58 (b), d
9.36 (c) and d 7.60 (a), d 7.53 (b), d 8.75 (c), respectively. From them
the new cyclometallated complexes were obtained (Scheme 1) and
they could be prepared by any one of three alternative methods, i.e.,
(Method 1) potassium tetrachloropalladate in ethanol; (Method 2)
lithium tetrachloropalladate in methanol; or (Method 3) palla-
dium(II) acetate in glacial acetic acid, leading in all cases to the tet-
ranuclear species [Pd{XC6H3C(Me)@NN@C(S)NHR}]4 (X = 3-F,
R@Me 1a, X = 4-F, R@Et 1b, X = 2-Br, R@Ph 1c) as air-stable solids,
with the ligand in the E,Z configuration, which were fully character-
ized (preparative details, characterizing microanalytical, mass
spectra, IR and 1H NMR data are in Section 3). The mass spectrum
(FAB) showed peaks at m/z 1320 (1a), 1375 (1b), 1810 (1c) for the
molecular ion whose isotopic composition suggests a tetranuclear
complex of formula C40H40F4N12Pd4S4 (1a), C44H48F4N12Pd4S4 (1b)
and C60H48F4N12Pd4S4 (1c) (see Section 3); this has been confirmed
The m(C@S) band disappears in the IR spectra of the complexes,
in accordance with loss of the double bond character upon depro-
tonation of the NH group; this was confirmed by the lengthening of
the C-S bond in the structures of 1a and 1c (vide infra). The absence
of the signal for the NH group in the 1H NMR spectra was in accor-
dance with deprotonation as observed in related coordination
compounds from these ligands [27,28]. Metallation of the ligands
was clear from the absence of the four proton spin system, ABCD
1a, 1c, and AA0XX0 1b, of the substituted phenyl ring; in the spectra
of the complexes only three resonances were observed, inclusive of
the coupling to the 19F nucleus where appropriate, which were
unambiguously assigned (see Section 3).
2.1. Reactivity of the complexes
Treatment of the tetranuclear species 1a–1c with the corre-
sponding diphosphine in a 1:2 molar ratio produced compounds
RHN
N
Me
N
S
Pd
Ph2
X
P
P
n
X
Ph2
Pd
N
S
Me
N
NHR
2a: n = 1; 3a: n = 2; 4a: n = 3; 5a: n = 4
2b: n = 1; 3b: n = 2; 4b: n = 3; 5b: n = 4
2c: n = 1; 3c: n = 2; 4c: n = 3; 5c: n = 4
Ph2
P
Pd
X
PPh2
n
N
S
Me
ii
N
NHR
4
n = 2, 3, 4
3
5
iii
X
6
X
i
Pd
N
Me
N
S
iv
Me
HN
S
N
NHR
NHR
Ph2
P
Pd
4
X
a: X = 3-F, R = Me
b: X = 4-F, R = Et
c: X = 2-Br, R = Ph
PPh2
1a, 1b, 1c
N
S
Me
N
v
NHR
7a, 7b, 7c,
n = 1
RHN
S
N
Me
N
Ph2
Pd
X
P
P
X
Pd
Ph2
N
S
Me
N
NHR
6a, 6b, 6c
Scheme 1. (i) K2[PdCl4]/EtOH; LiCl/PdCl2/NaAcO/MeOH; Pd(AcO)2/AcOH, as appropriate; (ii) Ph2P(CH2)nPPh2/acetone, n = 1–4; (iii) Ph2P(CH2)nPPh2/acetone, n = 2–4; (iv)
Ph2PCH2PPh2/acetone; (v) trans-Ph2PCH@CHPPh2/acetone.

J. Martínez et al. / Polyhedron 31 (2012) 217–226
219
[(Pd{XC6H3C(Me)@NN@C(S)NHR})2(
2a–c; 2, 3a–c; 3, 4a–c; 4, 5a–c), [(Pd{XFC6H3C(Me)@NN@C(S)
NHR})2( -Ph2PCH@CHPPh2)], ( 6a–c), with a bridging phos-
phine ligand, as pure air-stable solids, which were fully charac-
terized (see Scheme 1 and Section 3).
l
-Ph2P(CH2)nPPh2)], (n = 1,
deviations from the metal coordination plane. Each of the four palla-
dium atoms belongs to two fused five-membered chelate rings: the
C,N metallacycle and the N,S-chelate moiety, as a consequence of
bonding to a tridentate [C,N,S] ligand. For 3c the palladium atom is
bonded to four different donors, a tridentate thiosemicarbazone
through the aryl C(6) carbon, the imine N(1) nitrogen, and the thio-
amide S(1) sulfur atom, and to a phosphorus atom P(1) of the
l
The 1H NMR spectra the H5 resonance was high-field shifted ca.
1.4–0.7 ppm, with the largest shifts for the fluorine complexes, and
it was coupled to the 31P nucleus in agreement with a trans P to N
arrangement [29]. The symmetric nature of the complexes was put
forward by the 1H NMR spectra, which showed only one set of sig-
nals, and accordingly, a singlet was observed for the 31P resonance
due to the two equivalent phosphorus nuclei; the chemical shift
value for the latter also supported a phosphorus trans to nitrogen
coordination. [30–32].
bis(diphenylphosphino)ethane, Fig. 3, in
a slightly distorted
square-planar coordination, [Pd(1), C(6), N(1), S(1), P(1), plane 1]
(rms = 0.0109 Å). The Pd–C bond lengths, 1.979–2.006 Å 1a–1b,
and 2.047 Å 3c, are shorter than the expected value of 2.081 Å
[33], probably induced by partial multiple-bond character [22].
The angles between adjoining atoms in the coordination sphere
are close to the theoretical value of 90°, with the most noteworthy
strain in the Cphenyl–Pd–Nazomethine angle 80.9–81.5°, consequent
upon chelation. The C–S (1.763(12)–1.821(6) Å) and C–Nhydrazynic
[1.261(11)-1.297(7) Å] bond lengths show increased single and dou-
ble bond character, respectively, consequent upon deprotonation of
the hydrazynic group. For 1a and 1b the differing trans influence of
the phenyl carbon and the azomethine nitrogen atoms is put for-
ward in the distinct values of the Pd–Schelating and Pd–Sbridging dis-
tances, 2.337–2.3664 and 2.287–2.336 Å, respectively. The Pdꢁ ꢁ ꢁPd
distances within the ring, 3.389–3.452 Å, are greater than the sum
of the van der Waals radii [34] in all cases, precluding any metal-me-
tal interaction. In complex 3c all bond distances are within the ex-
pected range, with allowance for the strong trans influence of the
phosphorus donor ligand, which is reflected in the Pd(1)–N(1) dis-
tance of 2.008(5) Å (cf. sum of the covalent radii for palladium and
nitrogen, 2.01 Å [36]).
Reaction of 1a–1c with the short-bite diphosphine Ph2PCH2PPh2
in
a
1:4 molar ratio gave the mononuclear complexes
[Pd{XC6H3C(Me)@NN@C(S)NHR}(Ph2PCH2PPh2-P)] 7a–c (Scheme
1) as pure air-stable compounds. Characteristic microanalytical
and spectroscopic data are given in Section 3. Even when excess
diphosphine was used, only cleavage of the Pd–Sbridging bonds
was produced, therefore yielding species with coordination of the
phosphine to the metal atom only through one phosphorus atom.
The 31P NMR spectra showed two doublets assigned to the two
non-equivalent phosphorus nuclei; the resonance at higher fre-
quency was assigned to the 31P nucleus bonded to the metal cen-
ter. The resonance for the PCH2P protons (ABXY spin system)
appeared as an apparent doublet ca. 3.3 ppm. Attempts to produce
analogous mononuclear species with diphosphines other than
Ph2PCH2PPh2 were unsuccessful. (Scheme 1).
The palladium coordination plane is coplanar with the metalla-
cycle and with the coordination ring, e.g., for Pd(1) [Pd(1), C(6),
N(1), S(1), S(4), plane 1], [Pd(1), N(1), C(7), C(1), C(6), plane 2]
and [Pd(1), N(1), N(2), C(8), S(1), plane 3], respectively, with angles
between planes: 1/2 = 6.80(0.41)° 1a, 4.22(0.21)° 1b, 1/
3 = 8.19(0.24)° 1a, 5.66(0.15)° 1b, 2/3 = 9.50(0.42)° 1a, 5.82(0.22)°
1b); for 3c [Pd(1), C(6), N(1), S(1), P(1), plane 1], [Pd(1), C(6),
C(1), C(7), N(1), plane 2] and [Pd(1), N(1), N(2), C(8), S(1), plane
3] with angles between planes: 1/2 = 3.73, 2/3 = 2.42, 1/3 = 1.41°.
2.2. Molecular and crystal structures of 1a, 1b and 3c
Suitable crystals were grown by slowly evaporating chloroform/
n-hexane solutions. The crystal structures and the labeling scheme
for the ligands and the compounds are shown in Figs. 1–3. Crystal
data are given in Table 1, and selected bond lengths and angles in
Table 2.
For compounds 1a and 1b the core of the molecule consists of an
eight-membered ring of alternating palladium and sulfur atoms,
Figs. 1 and 2. The remaining two coordination sites of each palla-
dium atom are occupied by the phenyl carbon atom and the nitrogen
atom of the C@N group in slightly distorted square-planar environ-
ments, with rms values in the range 0.0056–0.0981, with small
2.3. Crystal packing: intra- and intermolecular interactions
A view of the crystal packing shows that compounds 1a and 1b
display interesting structural features. The C–Hꢁ ꢁ ꢁF parameters for
Fig. 1. An ORTEP drawing of the molecular structure for 1a with labeling scheme (30% probability). Hydrogen atoms have been omitted for clarity.

220
J. Martínez et al. / Polyhedron 31 (2012) 217–226
Fig. 2. An ORTEP drawing of the molecular structure for 1b with labeling scheme (30% probability). Hydrogen atoms have been omitted for clarity.
Fig. 3. An ORTEP drawing of the molecular structure for 3c with labeling scheme (30% probability). Hydrogen atoms have been omitted for clarity.
the interactions between molecules for 1a [C(2)–H(2)ꢁ ꢁ ꢁF(3A)#1:
0.930, 2.336, 3.215 Å, 157.37°, #1: x + 1/2, y + 1/2, z; C(32)–
H(32)ꢁ ꢁ ꢁF(1A)#3: 129.14, 2.447, 3.296 Å, 0.929°, #3: x ꢀ 1/2,
y ꢀ 1/2, z] suggest [35] close contacts between the fluorine atoms
and the phenyl rings of an adjacent molecule, which contribute
to formation of chains along the bisector of the a/b axes (Fig. 4
contacts between the a methoxy group and a metallated ring from
a neighboring molecule [Pd3, N7, C27, C21, C26] to give chains
along the b axis [C39–H39Cꢁ ꢁ ꢁCg(3)#5: 2.754, 3.675 Å, 160.31°,
#5: x, y + 1, z] (Fig. 5). Thus, the combined C–Hꢁ ꢁ ꢁF and C–Hꢁ ꢁ ꢁ
p
interactions in 1a lead to a two dimensional network of molecules
on the ab plane (Fig. 6). In addition, intramolecular C–Hꢁ ꢁ ꢁS short
contacts between the sulfur atoms and the phenyl groups have also
and Table 3). Furthermore, C–Hꢁ ꢁ ꢁ
p interactions produce short

J. Martínez et al. / Polyhedron 31 (2012) 217–226
221
Table 1
Crystallographic data and structure refinement data for 1a, 1b and 3c.
Compound
1a
1b
3c
Empirical formula
Formula weight
Temperature
Wavelength (Å)
Crystal system
Space group
Unit cell dimensions
a (Å)
C
40H40F4N12Pd4S4
C46H50Cl6F4N12Pd4S4
1613.52
293(2)
C56H50Br2Cl6N6P2Pd2S2
1542.42
293(2)
1318.68
293(2)
0.71073
monoclinic
C2/c
0.71073
0.71069
triclinic
triclinic
ꢀ
ꢀ
P1
P1
29.046(7)
13.372(3)
9.784(5)
b (Å)
10.099(3)
15.065(3)
12.728(5)
c (Å)
34.856(8)
16.611(3)
12.974(5)
a
b (°)
(°)
90
81.600(4)
77.678(4)
109.315(5)
97.737(5)
113.296(4)
c
(°)
90
9391(4)
8
1.865
1.746
5184
64.718(3)
2950.4(11)
2
1.816
1.670
1592
95.919(5)
1491.9(11)
1
1.717
2.379
V (Å3)
Z
Dcalc (Mg/m3)
Absorption coefficient (mmꢀ1
F(000)
)
766
Crystal size (mm3)
h range for data collection (°)
Index ranges
0.28 ꢂ 0.25 ꢂ 0.05
0.59 ꢂ 0.51 ꢂ 0.48
0.32 ꢂ 0.11 ꢂ 0.09
1.69–26.43
ꢀ12/h/12, ꢀ15/k/15, 0/l/16
6109
1.27–23.26
1.71–26.42
ꢀ32/h/29, 0/k/11, 0/l/38
6753
ꢀ16/h/9, ꢀ18/k/18, ꢀ20/l/20
24602
Reflections collected
Independent reflections (Rint
Completeness to h
)
6753 (0.0396)
100.0%
11946 (0.0249)
98.5%
6109 (0.0376)
99.5%
Absorption correction
Maximum and minimum transmission
Refinement method
Semi-empiric
0.9178 and 0.6406
Full-matrix least-squares on F2
6753/12/615
0.961
Semi-empiric
0.5011 and 0.4390
Full-matrix least-squares on F2
11946/20/701
1.009
Semi-empiric
0.869042 and 0.671473
Full-matrix least-squares on F2
6109/0/353
Data/restraints/parameters
Goodness-of-fit on F2
0.957
Final R indices [I > 2
R indices (all data)
Largest difference in peak and hole
r
(I)]
R1 = 0.0463, wR2 = 0.0992
R1 = 0.0973, wR2 = 0.1067
0.865 and ꢀ0.664
R1 = 0.0418, wR2 = 0.1152
R1 = 0.0667, wR2 = 0.1319
1.419 and ꢀ1.030
R1 = 0.0502, wR2 = 0.1025
R1 = 0.1219, wR2 = 0.1238
0.920 and ꢀ1.109
Table 2
Selected bond lengths (Å) and angles (°) for 1a, 1b and 3c.
1a
1b
3c
1a
1b
3c
Pd(1)–C(6)
Pd(1)–N(1)
Pd(1)–S(1)
Pd(1)–S(4)
Pd(1)–P(1)
C(1)–C(7)
C(7)–N(1)
N(1)–N(2)
N(2)–C(8)
C(8)–S(1)
1.979(9)
1.993(7)
2.353(2)
2.317(2)
2.006(5)
2.003(5)
2.3664(16)
2.2997(16)
2.047(7)
2.008(5)
2.3209(19)
C(6)–Pd(1)–N(1)
80.9(4)
81.9(2)
101.38(9)
95.9(3)
176.6(2)
160.3(3)
81.3(2)
80.2(2)
83.32(16)
N(1)–Pd(1)–S(1)
S(1)–Pd(1)–S(4)
C(6)–Pd(1)–S(4)
N(1)–Pd(1)–S(4)
C(6)–Pd(1)–S(1)
S(1)–Pd(1)–P(1)
C(6)–Pd(1)–P(1)
N(1)–Pd(1)–P(1)
82.79(14)
101.23(5)
94.82(19)
175.78(14)
162.97(18)
2.2637(18)
1.475(8)
1.308(7)
1.383(7)
1.319(8)
1.743(7)
1.474(13)
1.296(11)
1.377(9)
1.281(11)
1.773(9)
1.428(9)
1.309(7)
1.376(7)
1.283(7)
1.821(6)
163.53(18)
98.90(6)
97.57(18)
175.97(16)
Fig. 4. Crystal packing of 1a. Ortep representation of molecular chains along the bisector of the a/b axes. Dashed lines show the C–Hꢁ ꢁ ꢁF interactions.

222
J. Martínez et al. / Polyhedron 31 (2012) 217–226
Table 3
Intra- and intermolecular interactions for 1a.
D–Hꢁ ꢁ ꢁA interactionsa
D–H
Hꢁ ꢁ ꢁA
Dꢁ ꢁ ꢁA
D–Hꢁ ꢁ ꢁA
C2–H2ꢁ ꢁ ꢁF(3A)#1
C15–H15ꢁ ꢁ ꢁS3
C25–H3Bꢁ ꢁ ꢁS1
C35–H4Bꢁ ꢁ ꢁS2
C5–H5ꢁ ꢁ ꢁS4
0.930
1.040
1.033
1.010
0.930
0.959
0.961
0.959
0.929
0.960
2.336
2.830
2.817
2.871
2.810
2.421
2.606
2.325
2.447
2.308
a
3.215
3.383
3.356
3.438
3.334
2.794
3.446
2.737
3.296
2.744
b
157.37
113.57
112.86
116.16
116.78
102.77
146.07
105.12
129.14
106.82
c
28.32
9.37
25.99
19.94
24.64
C10–H10Cꢁ ꢁ ꢁN2
C20–H20Bꢁ ꢁ ꢁN9#2
C30–H30Cꢁ ꢁ ꢁN8
C32–H32ꢁ ꢁ ꢁF1A#3
C40–H40Cꢁ ꢁ ꢁN11
p
ꢁ ꢁ ꢁ
p
interactions
Cgꢁ ꢁ ꢁCg
Cg(1)ꢁ ꢁ ꢁCg(2)
Cg(1)ꢁ ꢁ ꢁCg(5)
Cg(3)ꢁ ꢁ ꢁCg(4)
Cg(4)ꢁ ꢁ ꢁCg(6)
Cg(6)ꢁ ꢁ ꢁCg(7)
3.816
3.431
3.821
3.608
3.838
Hꢁ ꢁ ꢁCg
2.905
2.754
5.35
3.81
5.00
4.96
29.10
7.58
30.34
15.41
25.02
C–Hꢁ ꢁ ꢁCg
145.91
160.31
5.91
C–Hꢁ ꢁ ꢁ
p
interactionsa
Cꢁ ꢁ ꢁCg
3.711
3.675
C24–H24ꢁ ꢁ ꢁCg(1)#4
C39–H39Cꢁ ꢁ ꢁCg(3)#5
Cg rings (1): Pd1, N1, C7, C1, C6; (2): Pd2, N4, C11, C16, C17; (3): Pd3, N7,
C27, C21, C26; (4): Pd4, N10, C37, C31, C36; (5): C11–C16; (6): C21–C26; (7): C31–C36.
a
Symetry code: #1: x + 1/2, y + 1/2, z; #2: 3/2 ꢀ x, y + 1/2, 3/2 ꢀ z; #3: x ꢀ 1/2, y ꢀ 1/2, z; #4: 1 ꢀ x, ꢀy, 1 ꢀ z; #5: x, y + 1, z.
been observed for both 1a and 1b, as well as C–Hꢁꢁꢁ
p
interactions in 1b,
7.44 (m, 2H, H2, H6), 7.37 (td, 1H, H5, 3JH5H4 = 8.3 Hz, 4JH5F = 5.5 Hz),
7.10 (tdd, 1H, H4, 3JH4H5 = 8.3 Hz, 3JH4F = 8.3 Hz, 4JH4H2 = 2.3 Hz), 3.28
(d, 3H, NHCH3, 3JHH = 4.6 Hz), 2.26 (s, 3H, CH3C@N). FAB-MS: m/z 226
[MH]+.
involving a chloroform solvent molecule [C(99)–H99CꢁꢁꢁCg(3)#2: 2.596,
3.517 Å, 156.71°, #2: ꢀx, 1 ꢀ y, 1 ꢀ z] (Supporting information).
Lingand b was synthesized following a similar procedure.
3. Experimental
3.2.2. 4-FC6H4C(Me)@NN(H)C(@S)NHEt b
3.1. General procedures
Yield: >95%. Anal. Calc. C11H14FN3S (239.3 g/mol): C, 55.2; H,
5.9; N, 17.6; S, 13.4. Found: C, 55.3; H, 5.7; N, 17.4; S, 13.3%. IR
Solvents were purified by standard methods [36]. Chemicals
were reagent grade. Lithium tetrachloropalladate was prepared
in situ by treatment of palladium(II) chloride with lithium chloride
in methanol. Palladium(II) acetate, palladium(II) chloride and
potassium tetrachloropalladate(II) were purchased from Alfa Prod-
ucts. The phosphines Ph2PCH2PPh2 (dppm), Ph2P(CH2)2PPh2
(dppe), trans-Ph2P(CH@CH)PPh2 (t-dppe), Ph2P(CH2)3PPh2 (dppp)
and Ph2P(CH2)4PPh2 (dppb) were purchased from Aldrich-Chemie.
Microanalyses were carried out at the Servicio de Análisis Elemen-
tal at the Universidad de Santiago de Compostela using a Carlo Erba
Elemental Analyzer Model EA1108. IR spectra were recorded as
Nujol mulls or KBr discs with a Perkin–Elmer 1330, with an IR-FT
Mattson Model Cygnus-100 and with a Bruker Model IFS-66 V
spectrophotometers. NMR spectra were obtained as CDCl3 solu-
(cmꢀ1):
m
(N–H) 3359 m, 3211 m;
m(C@N) 1619 m; m(C@S) 833s.
1H NMR (CDCl3): d 8.58 (s, 1H, NH), 7.53 (br, 1H, NHEt), 7.68 (dd,
3
4
2H, H2, H6, JH2H3 = 9.1 Hz, JH2F = 5.3 Hz), 7.09 (t, 2H, H3, H5,
3JH3F = 9.1 Hz, 3JH5F = 9.1 Hz), 3.77 (dq, 2H, NHCH2CH3,
3
3JHH = 7.2 Hz, JH–NH = 5.7 Hz), 2.25 (s, 3H, CH3C@N), 1.31 (t, 3H,
3
NHCH2CH3, JHH = 7.2 Hz). FAB-MS: m/z 240 [MH]+.
3.2.3. 2-BrC6H4C(Me)@NN(H)C(@S)NHPh c
20-Bromoacetophenone (119 mg, 5.98 mmol) and hydrochloric
acid (35%, 0.65 cm3) were added to a suspension of 4-phenyl-3-thi-
osemicarbazide (100 mg, 5.98 mmol) in water (25 cm3) to give a
clear solution, which was stirred at room temperature for 4 h.
The white solid that precipitated was filtered off, washed with cold
water, and dried in air. Yield: 93%. Anal.Calc. C15H14BrN3S (348.3 g/
mol): C, 51.7; H, 4.1; N, 12.1; S, 9.2. Found: C, 51.5; H, 4.3; N, 12.3;
tions and referenced to SiMe4 (1H) or 85% H3PO4 31P–{1H}) and
(
were recorded with Bruker AMX 300, AMX 500 and WM 250 spec-
trometers. All chemical shifts are reported downfield from stan-
dards. The FAB mass spectra were recorded with a Fisons Quatro
mass spectrometer with a Cs ion gun; 3-nitrobenzyl alcohol was
used as the matrix.
S, 8.9%. IR (cmꢀ1):
m(N–H) 3293s, 3196 m; m(C@N) 1594 m; m(C@S)
799 m. 1H NMR (CDCl3): d 9.36 (br, 1H, NH), 8.75 (s, 1H, NHPh),
3
4
7.71 (dd, 1H, H6, JH6H5 = 7.9 Hz, JH6H4 = 1.4 Hz), 7.42 (m, 3H, H3,
H4, H5), 2.35 (s, 3H, CH3C@N). FAB-MS: m/z 348 [M]+.
3.2. Syntheses
3.2.4. [Pd{3-FC6H3C(Me)@NN@C(S)NHMe}]4 1a
Method 1: To a stirred solution of potassium tetrachloropalla-
date (200 mg, 0.61 mmol) in water (6 mL) was added ethanol
(40 mL). The fine yellow suspension of potassium tetrachloropalla-
date obtained was treated with 3-FC6H4C(Me)@NN(H)C(@S)NHMe
(a) (152 mg, 0.67 mmol, 10% excess). The mixture was stirred for
48 h at room temperature under nitrogen. The yellow precipitate
was filtered off, washed with ethanol and dried. Yield: 95%. Anal.
Calc. C40H40F4N12Pd4S4 (1318.8 g/mol): C, 36.4; H, 3.1; N, 12.7; S,
3.2.1. 3-FC6H4C(Me)@NN(H)C(@S)NHMe a
30-Fluoroacetophenone (1,314 g, 9.51 mmol) and hydrochloric
acid (35%, 0.65 mL) were added to a suspension of 4-methyl-3-thio-
semicarbazide (1,000 g, 9.51 mmol) in water (25 cm3) to give a clear
solution, which was stirred at room temperature for 4 h. The white
solid that precipitated was filtered off, washed with cold water,
and dried in air. Yield: 95%. Anal. Calc. C10H12FN3S (225.3 g/mol):
C, 53.3; H, 5.4; N, 18.7; S, 14.2. Found: C, 53.5; H, 5.5; N, 18.8; S,
9.7. Found: C, 36.4; H, 3.2; N, 12.5; S, 9.6%. IR (cmꢀ1):
3418 m; (C@N) 1561 m. 1H NMR (CDCl3): d 7.35 (dd, 1H, H5,
3JH5H4 = 8.3 Hz, JH5F = 5.5 Hz), 6.67 (m, 1H, H4), 6.52 (dd, 1H, H2,
m(N–H)
14.0%. IR (cmꢀ1):
818 m. 1H NMR (CDCl3): d 8.63 (s, 1H, NH), 7.60 (br, 1H, NHMe),
m(N–H) 3387s, 3215s;
m
(C@N) 1603w;
m
(C@S)
m
4

J. Martínez et al. / Polyhedron 31 (2012) 217–226
223
3JH2F = 10.2 Hz, 4JH2H4 = 2.8 Hz), 5.11 (q, 1H, NHMe, 3JNH–H = 5.1 Hz),
2.98 (d, 3H, NHCH3, 3JH–NH = 5.1 Hz), 1.78 (s, 3H, CH3C@N). FAB-MS:
m/z 1320 [MꢀH]+.
Method 2: Ligand 1 (326 mg, 0.94 mmol, 5% excess) and palla-
dium(II) acetate (200 mg, 0.89 mmol) were added to glacial acetic
acid (45 cm3) to give a clear solution, which was heated to 60 °C
under nitrogen for 24 h. After this had cooled to room temperature,
the yellow precipitate was filtered off, washed with ethanol, and
dried. Yield: 79%.
Method 2: Ligand a (267 mg, 1.18 mmol, 5% excess) and sodium
acetate (185 mg, 2.26 mmol) were added to a stirred solution of
palladium(II) chloride (200 mg, 1.13 mmol) and lithium chloride
(96 mg, 2.26 mmol) in methanol (40 mL). The mixture was stirred
for 48 h at room temperature under nitrogen. The yellow precipi-
tate was filtered off, washed with methanol, and dried. Yield: 95%.
Method 3: Ligand a (210 mg, 0.94 mmol, 5% excess) and palla-
dium(II) acetate (200 mg, 0.89 mmol) were added to glacial acetic
acid (45 mL) to give a clear solution, which was heated to 60 °C un-
der nitrogen for 24 h. After this had cooled to room temperature,
the yellow precipitate was filtered off, washed with ethanol, and
dried. Yield: 80%.
3.2.7. [(Pd{3-FC6H3C(Me)@NN@C(S)NHMe})2(l-Ph2PCH2PPh2)] 2a
The diphosphine PPh2CH2PPh2 (18 mg, 0.046 mmol) was added
to a suspension of complex 1a (30 mg, 0.023 mmol) in acetone
(15 cm3). The mixture was stirred for 4 h and the resulting yellow
solid was filtered off and dried. Yield: 51%. Anal.
Calc.
C
45H42F2N6P2Pd2S2 (1043.8 g/mol): C, 51.8; H, 4.1; N, 8.1; S, 6.1.
Found: C 51.5; H 4.0; N 7.9; S 5.9%. IR (cmꢀ1):
m
(N–H) 3434 m;
m
(C@N) 1567 m. 1H NMR(CDCl3): d 6.59 (dd, 1H, H2, 3JH2F = 10.6 Hz,
4JH2H4 = 2.8 Hz), 6.00 (m, 2H, H4, H5), 4.84 (q, 1H, NHMe, JNH–
3
Compounds 1b–1d: These were synthesized following a similar
procedure.
H = 5.1 Hz), 3.75 (t, 1H, PCH2P), 3.02 (d, 3H, NHCH3, 3JH–NH = 5.1 Hz),
2.28 (s, 3H, CH C@N). 31P–{1H} NMR (CDCl3): d 24.2 (s).
3
Compounds 2b–2d, 3a–3d, 4a–4d, 5a–5d and 6a–6d: These were
synthesized following a similar procedure.
3.2.5. [Pd{4-FC6H3C(Me)@NN@C(S)NHEt}]4 1b
Method 1: Yield: 95%. Anal. Calc. C44H48F4N12Pd4S4 (1374.9 g/
mol): C, 38.4; H, 3.5; N, 12.2; S, 9.3. Found: C, 38.5; H, 3.5; N,
3.2.8. [(Pd{4-FC6H3C(Me)@NN@C(S)NHEt})2(l-Ph2PCH2PPh2)] 2b
12.1; S, 9.2%. IR (cmꢀ1):
m(N–H) 3431 m, m(C@N) 1584 m. 1H
Yield: 58%. Anal.Calc. C47H46F2N6P2Pd2S2 (1071.8 g/mol): C, 52.7;
3
4
NMR (CDCl3): d 7.18 (dd, 1H, H5, JH5F = 8.8 Hz, JH5H3 = 2.8 Hz),
H, 4.3; N, 7.8; S, 6.0. Found: C, 52.6; H, 4.4; N, 7.8; S, 5.9%. IR (cmꢀ1):
3
4
6.74 (dd, 1H, H2, JH2H3 = 8.3 Hz, JH2F = 5.1 Hz), 6.58 (td, 1H, H3,
m
(N–H) 3430 m; m(C@N) 1582 m. 1H NMR(CDCl3): d 6.84 (dd, 1H, H2,
3
4
3JH3F = 8.3 Hz, JH3H2 = 8.3 Hz, JH3H5 = 2.8 Hz), 5.02 (t, 1H, NHEt,
4
3
3JH2H3 = 8.3 Hz, JH2F = 5.5 Hz), 6.35 (td, 1H, H3, JH3F = 8.3 Hz,
3JNH–H = 5.5 Hz), 3.42 (m, 2H, NHCH2CH3), 1.81 (s, 3H, CH3C@N),
4
3
3JH3H2 = 8.3 Hz, JH3H5 = 2.3 Hz), 5.79 (ddd, 1H, H5, JH5F = 9.2 Hz,
3
1.25 (t, 3H, NHCH2CH3, JHH = 7.4 Hz). FAB-MS: m/z 1375 [M]+.
4JH5P = 4.2 Hz, JH5H3 = 2.3 Hz), 4.76 (br, 1H, NHEt), 3.77 (t, 1H,
4
Method 2: Yield: 95%.
Method 3: Yield: 87%.
3
3
PCH2P), 3.43 (dq, 2H, NHCH2CH3, JHH = 7.4 Hz, JH–NH = 4.6 Hz),
2.29 (s, 3H, CH3C@N), 1.22 (t, 3H, NHCH2CH3, JHH = 7.4 Hz). 31P–
3
{1H} NMR (CDCl3): d 23.6 (s).
3.2.6. [Pd{2-BrC6H3C(Me)@NN@C(S)NHPh}]4 1c
3.2.9. [(Pd{2-BrC6H3C(Me)@NN@C(S)NHPh})2(l-Ph2PCH2PPh2)] 2c
Method 1: Ligand 1 (412 mg, 1.18 mmol, 5% excess) and sodium
acetate (185 mg, 2.26 mmol) were added to a stirred solution of
palladium(II) chloride (200 mg, 1.13 mmol) and lithium chloride
(96 mg, 2.26 mmol) in methanol (40 cm3). The mixture was stirred
for 48 h at room temperature under nitrogen. The yellow precipi-
tate was filtered off, washed with methanol, and dried. Yield:
94%. Anal. Calc. C60H48Br4N12Pd4S4 (1810.7 g/mol): C, 39.8; H, 2.7;
N, 9.3; S, 7.1. Found: C, 39.7; H, 2.8; N, 9.1; S, 6.9%. IR (cmꢀ1):
Yield: 36%. Anal. Calc. C55H46Br2N6P2Pd2S2 (1289.7 g/mol): C,
51.2; H, 3.6; N, 6.5; S, 5.0. Found: C, 50.9; H, 3.8; N, 6.5; S, 4.7%.
IR (cmꢀ1):
m(N–H) 3411 m; m(C@N) 1554 m. 1H NMR (CDCl3): d
6.95 (m, 1H, H3), 6.73 (s, 1H, NHPh), 6.56 (m, 2H, H4, H5), 3.76
2
(t, 1H, PCH2P, JHP = 9.2 Hz), 2.71 (s, 3H, CH3C@N). 31P–{1H} NMR
(CDCl3): d 23.7 (s).
m
(N–H) 3402 m;
m
(C@N) 1553s. 1H NMR (CDCl3): d 7.30 (d, 1H,
H5, JH5H4 = 7.9 Hz), 7.08 (m, 1H, H3), 6.94 (s, 1H, NHPh), 6.53 (t,
3.2.10. [(Pd{3-FC6H3C(Me)@NN@C(S)NHMe})2(l-Ph2P (CH2)2PPh2)]
3a
Yield: 68%. Anal. Calc. C46H44F2N6P2Pd2S2 (1057.8 g/mol): C,
52.2; H, 4.2; N, 7.9; S, 6.1. Found: C, 51.9; H, 4.0; N, 7.8; S, 6.0%.
3
3
3
1H, H4, JH4H3 = 7.9 Hz, JH4H5 = 7.9 Hz), 2.24 (s, 3H, CH3C@N).
FAB-MS: m/z 1810 [M]+.
Fig. 5. Representation of
p–p
and C–Hꢁ ꢁ ꢁ
p
interactions of 1a. Dashed lines show the interactions.

224
J. Martínez et al. / Polyhedron 31 (2012) 217–226
Fig. 6. Representation of the combined C–Hꢁ ꢁ ꢁF,
p–p and C–Hꢁ ꢁ ꢁp interactions in 1a producing a two dimensional network of molecules on the ab plane.
3
4
IR (cmꢀ1):
m
(N–H) 3422s;
m
(C@N) 1566 m. 1H NMR(CDCl3): d 6.78
7.01 (dd, 1H, H2, JH2H3 = 8.8 Hz, JH2F = 5.5 Hz), 6.51 (td, 1H, H3,
3
4
3
4
(dd, 1H, H2, JH2F = 10.6 Hz, JH2H4 = 2.8 Hz), 6.19 (m, 2H, H4, H5),
3JH3F = 8.8 Hz, JH3H2 = 8.8 Hz, JH3H5 = 2.8 Hz), 5.98 (ddd, 1H, H5,
3
4
4
4.79 (br, 1H, NHMe), 2.99 (d, 3H, NHCH3, JH–NH = 5.1 Hz), 2.80
3JH5F = 9.2 Hz, JH5P = 4.2 Hz, JH5H3 = 2.8 Hz), 4.75 (t, 1H, NHEt,
(br, 2H, P(CH2)2P), 2.36 (s, 3H, CH3C@N). 31P–{1H} NMR (CDCl3):
d 32.4 (s).
3JNH–H = 5.5 Hz), 3.42 (dq, 2H, NHCH2CH3, JHH = 7.4 Hz, JH–
3
3
NH = 5.5 Hz), 2.54 (m, 2H, PCH2CH2CH2P), 2.34 (s, 3H, CH3C@N),
3
2.09 (br, 1H, PCH2CH2CH2P), 1.20 (t, 3H, NHCH2CH3, JHH = 7.4 Hz).
31P–{1H} NMR (CDCl3): d 27.1 (s).
3.2.11. [(Pd{4-FC6H3C(Me)@NN@C(S)NHEt})2(l-Ph2P (CH2)2PPh2)] 3b
Yield: 84%. Anal. Calc. C48H48F2N6P2Pd2S2 (1085.9 g/mol): C,
53.1; H, 4.5; N, 7.7; S, 5.9. Found: C 53.2; H 4.5; N 7.6; S 5.8%. IR
3.2.15. [(Pd{2-BrC6H3C(Me)@NN@C(S)NHPh})2(-Ph2P(CH2)3PPh2)] 4c
Yield: 38%. Anal. Calc. C57H50Br2N6P2Pd2S2 (1317.8 g/mol): C,
52.0; H, 3.8; N, 6.4; S, 4.9. Found: C, 52.2; H, 3.9; N, 6.2; S, 4.7%.
(cmꢀ1):
m(N–H) 3399 m; m(C@N) 1580 m. 1H NMR(CDCl3): d 7.02
3
4
(dd, 1H, H2, JH2H3 = 8.8 Hz, JH2F = 5.5 Hz), 6.51 (td, 1H, H3,
3
4
3JH3F = 8.8 Hz, JH3H2 = 8.8 Hz, JH3H5 = 2.3 Hz), 5.94 (m, 1H, H5),
IR (cmꢀ1):
m(N–H) 3396 m; m(C@N) 1560 m. 1H NMR (CDCl3): d
3
4.74 (t, 1H, NHEt, JNH–H = 5.5 Hz), 3.40 (dq, 2H, NHCH2CH3,
7.10 (m, 1H, H3), 6.74 (s, 1H, NHPh), 6.34 (m, 2H, H4, H5), 2.82
(s, 3H, CH3C@N), 2.56 (m, 2H, PCH2CH2CH2P), 2.08 (br, 1H,
PCH2CH2CH2P). 31P–{1H} NMR (CDCl3): d 26.8 (s).
3JHH = 7.4 Hz, JH–NH = 5.5 Hz), 2.77 (br, 2H, P(CH2)2P), 2.35 (s, 3H,
3
3
CH3C@N), 1.19 (t, 3H, NHCH2CH3, JHH = 7.4 Hz). 31P–{1H} NMR
(CDCl3): d 32.0 (s).
3.2.16. [(Pd{3-FC6H3C(Me)@NN@C(S)NHMe})2(-Ph2P(CH2)4PPh2)] 5a
Yield: 43%. Anal. Calc. C48H48F2N6P2Pd2S2 (1085.9 g/mol): C,
53.1; H, 4.5; N, 7.7; S, 5.9. Found: C, 52.9; H, 4.4; N, 7.5; S, 5.8%.
3.2.12. [(Pd{2-BrC6H3C(Me)@NN@C(S)NHPh})2(l-Ph2P(CH2)2PPh2)]
3c
Yield: 48%. Anal. Calc. C56H48Br2N6P2Pd2S2 (1303.8 g/mol): C,
IR (cmꢀ1):
m(N–H) 3429 m; m(C@N) 1566 m. 1H NMR(CDCl3): d
3
4
51.6; H, 3.7; N, 6.4; S, 4.9. Found: C 51.5; H 3.7; N 6.3; S 4.8%. IR
6.77 (dd, 1H, H2, JH2F = 10.6 Hz, JH2H4 = 1.9 Hz), 6.25 (m, 2H, H4,
3
(cmꢀ1):
m
(N–H) 3397 m;
m
(C@N) 1556 m. 1H NMR (CDCl3): d 7.11
H5), 4.81 (br, 1H, NHMe), 2.97 (d, 3H, NHCH3, JH–NH = 4.6 Hz),
3
4
(dd, 1H, H3, JH3H4 = 7.4 Hz, JH3H5 = 1.4 Hz), 6.69 (s, 1H, NHPh),
6.30 (m, 2H, H4, H5), 2.85 (s, 3H, CH<S@N), 2.84 (br, 2H,
P(CH2)2P). 31P–{1H} NMR (CDCl3): d 32.5 (s).
2.33 (s, 3H, CH3C@N), 2.29 (br, 2H, PCH2CH2CH2CH2P), 1.76 (br,
2H, PCH2CH2CH2CH2P). 31P–{1H} NMR (CDCl3): d 29.2 (s).
3.2.17. [(Pd{4-FC6H3C(Me)@NN@C(S)NHEt})2(-Ph2P(CH2)4PPh2)] 5b
Yield: 61%. Anal. Calc. C50H52F2N6P2Pd2S2 (1113.9 g/mol): C,
53.9; H, 4.7; N, 7.5; S, 5.8. Found: C, 54.1; H, 5.0; N, 7.6; S, 5.6%.
3.2.13. [(Pd{3-FC6H3C(Me)@NN@C(S)NHMe})2(l-Ph2P(CH2)3PPh2)]
4a
Yield: 42%. Anal. Calc. C47H46F2N6P2Pd2S2 (1071.8 g/mol): C,
IR (cmꢀ1):
m(N–H) 3430 m; m(C–N) 1577 m. 1H NMR(CDCl3): d
3
4
52.7; H, 4.3; N, 7.8; S, 6.0. Found: C, 52.4; H, 4.1; N, 7.6; S, 5.9%.
7.02 (dd, 1H, H2, JH2H3 = 8.8 Hz, JH2F = 5.5 Hz), 6.52 (td, 1H, H3,
IR (cmꢀ1):
m
(N–H) 3425 m;
m
(C@N) 1566 m. 1H NMR(CDCl3): d
3JH3F = 8.8 Hz, JH3H2 = 8.8 Hz, JH3H5 = 2.8 Hz), 6.01 (m, 1H, H5),
3
4
3
3
3
6.76 (d, 1H, H2, JH2F = 10.6 Hz), 6.22 (m, 2H, H4, H5), 4.84 (br,
1H, NHMe), 2.98 (d, 3H, NHCH3, JH–NH = 4.6 Hz), 2.59 (m, 2H,
4.73 (br, 1H, NHEt), 3.40 (dq, 2H, NHCH2CH3, JHH = 7.4 Hz, JH–
NH = 5.5 Hz), 2.36 (s, 3H, CH3C@N), 2.30 (br, 2H, PCH2CH2CH2CH2P),
1.75 (br, 2H, PCH2CH2CH2CH2P), 1.18 (t, 3H, NHCH2CH3,
3JHH = 7.4 Hz). 31P–{1H} NMR (CDCl3): d 8.7 (s).
3
PCH2CH2CH2P), 2.33 (s, 3H, CH3C@N), 2.16 (br, 1H, PCH2CH2CH2P).
31P–{1H} NMR (CDCl3): d 27.3 (s).
3.2.14. [(Pd{4-FC6H3C(Me)@NN@C(S)NHEt})2(-Ph2P(CH2)3PPh2)] 4b
Yield: 60%. Anal. Calc. C49H50F2N6P2Pd2S2 (1099.9 g/mol): C,
53.5; H, 4.6; N, 7.6; S, 5.8. Found: C, 53.3; H, 4.5; N, 7.4; S, 5.7%.
3.2.18. [(Pd{2-BrC6H3C(Me)@NN@C(S)NHPh})2(-Ph2P(CH2)4PPh2)] 5c
Yield: 51%. Anal. Calc. C58H52Br2N6P2Pd2S2 (1331.8 g/mol): C,
52.3; H, 3.9; N, 6.3; S, 4.8. Found: C, 52.0; H, 4.0; N, 6.1; S, 4.7%.
IR (cmꢀ1):
m
(N–H) 3429 m;
m
(C@N) 1581 m. 1H NMR(CDCl3): d
IR (cmꢀ1):
m(N–H) 3401 m; m(C@N) 1553 m. 1H NMR (CDCl3): d

J. Martínez et al. / Polyhedron 31 (2012) 217–226
225
3
4
7.09 (dd, 1H, H3, JH3H4 = 7.9 Hz, JH3H5 = 1.4 Hz), 6.78 (s, 1H,
NHPh), 6.56 (m, 1H, H4), 6.37 (m, 1H, H5), 2.84 (s, 3H, CH3C@N),
2.30 (br, 2H, PCH2CH2CH2CH2P), 1.76 (br, 2H, PCH2CH2CH2CH2P).
31P–{1H} NMR (CDCl3): d 28.7 (s).
solid was filtered off and dried. Yield: 48%. Anal.
Calc.
C
40H34BrN3P2PdS (837.1 g/mol): C, 57.4; H, 4.1; N, 5.0; S, 3.8.
Found: C, 57.1; H, 4.1; N, 4.8; S, 3.6%. IR (cmꢀ1):
(N–H) 3396 m;
(C@N) 1545 m. 1H NMR (CDCl3): d 7.01 (m, 1H, H3), 6.36 (m,
m
m
2
1H, H4), 6.20 (m, 1H, H5), 3.29 (d, 2H, PCH2P, JHP = 9.2 Hz), 2.78
3.2.19. [(Pd{3-FC6H3C(Me)@NN@C(S)NHMe})2(-Ph2PCH@CHPPh2)]
6a
Yield: 73%. Anal. Calc. C46H42F2N6P2Pd2S2 (1055.8 g/mol): C,
52.3; H, 4.0; N, 8.0; S, 6.1. Found: C, 52.0; H, 3.8; N, 7.8; S, 5.9%.
m(N–H) 3419s; m(C@N) 1566 m. 1H NMR(CDCl3): d
6.76 (d, 1H, H2, JH2F = 10.6 Hz), 6.25 (m, 1H, H5), 6.06 (m, 1H,
(s, 3H, CH3C@N). 31P–{1H} NMR (CDCl3): d 23.7 (d, 1P, PA,
2JPP = 75.1 Hz), ꢀ26.7 (d, 1P, PB, JPP = 75.1 Hz).
2
3.3. Crystal structures
IR (cmꢀ1):
3
Crystals of 1a, 1bꢁ2CHCl3 and 3cꢁCHCl3 were mounted on a glass
fiber and transferred to the diffractometer. Three dimensional,
room temperature X-ray data were collected with Bruker SMART
CCD diffractometer by the omega scan method, using monochro-
3
H4), 4.76 (br, 1H, NHMe), 2.93 (d, 3H, NHCH3, JH–NH = 5.1 Hz),
2.34 (s, 3H, CH3C@N). 31P–{1H} NMR (CDCl3): d 32.9 (s).
3.2.20. [(Pd{4-FC6H3C(Me)@NN@C(S)NHEt})2(-Ph2PCH@CHPPh2)] 6b
Yield: 66%. Anal. Calc. C48H46F2N6P2Pd2S2 (1083.8 g/mol): C,
53.2; H, 4.3; N, 7.8; S, 5.9. Found: C, 53.0; H, 4.2; N, 7.7; S, 5.7%.
mated MoK
a radiation. All the measured reflections were cor-
rected for Lorentz and polarization effects and for absorption by
semiempirical methods based on symmetry-equivalent and re-
peated reflections [Tmax/Tmin = 0.9178/0.6406 (1a), 0.5011/0.4390
(1b) and 0.869042/0.671473 (3c)]. The structures were solved by
direct methods and refined by full matrix least squares on F2.
Hydrogen atoms were included in calculated positions and refined
in riding mode. Refinement converged at a final R = 0.0463 (1a),
0.0418 (1b) and 0.0502 (3c) (observed data, F), and wR2 = 0.1067
(1a), 0.1319 (1b) and 0.1238 (3c) (all unique data, F2), with allow-
ance for thermal anisotropy of all non-hydrogen atoms. Minimum
and maximum final electron densities: ꢀ0.664 and 0.865 (1a),
ꢀ1.030 and 1.419 e Åꢀ3 (1b) and ꢀ1.109 and 0.920 e Åꢀ3 (3c).
The structure solutions and refinements were carried out with
the SHELX-97 [37] program package.
IR (cmꢀ1):
m
(N–H) 3434 m;
m
(C@N) 1587s. 1H NMR(CDCl3): d 7.10
3
4
(dd, 1H, H2, JH2H3 = 8.3 Hz, JH2F = 5.5 Hz), 6.58 (td, 1H, H3,
3JH3F = 8.3 Hz, JH3H2 = 8.3 Hz, JH3H5 = 2.3 Hz), 6.00 (m, 1H, H5),
3
4
3
3
4.74 (br, 1H, NHEt), 3.38 (dq, 2H, NHCH2CH3, JHH = 7.4 Hz, JH–
NH = 5.5 Hz), 2.51 (s, 3H, CH3C@N), 1.21 (t, 3H, NHCH2CH3,
3JHH = 7.4 Hz). 31P–{1H} NMR (CDCl3): d 32.7 (s).
3.2.21. [(Pd{2-BrC6H3C(Me)@NN@C(S)NHPh})2(-Ph2PCH@CHPPh2)]
6c
Yield: 41%. Anal. Calc. C56H46Br2N6P2Pd2S2 (1301.7 g/mol): C,
51.7; H, 3.6; N, 6.5; S, 4.9. Found: C, 51.4; H, 3.5; N, 6.3; S, 4.7%.
IR (cmꢀ1):
m(N–H) 3406s;
m(C@N) 1553 m. 1H NMR (CDCl3): d
7.05 (m, 1H, H3), 6.78 (s, 1H, NHPh), 6.39 (m, 1H, H5), 6.26 (t,
3
3
1H, H4, JH4H3 = 7.9 Hz, JH4H5 = 7.9 Hz), 2.84 (s, 3H, CH3C@N).
31P–{1H} NMR (CDCl3): d 32.5 (s).
Acknowledgments
We thank the Xunta de Galicia (projects 10DPI209017PR and
10PXIB209226PR) for financial support. J. Martínez acknowledges
an Isidro Parga Pondal contract from the Xunta de Galicia.
3.2.22. Preparation of [Pd{3-
FC6H3C(Me)@NN@C(S)NHMe}(Ph2PCH2PPh2-P)] 7a
The diphosphine PPh2CH2PPh2 (60 mg, 0.155 mmol) was added
to a suspension of complex 1a (50 mg, 0.038 mmol) in acetone
(15 cm3). The mixture was stirred for 4 h. The resulting yellow so-
lid was filtered off and dried. Yield: 65%. Anal.Calc. C35H32FN3P2PdS
(714.1 g/mol): C, 58.9; H, 4.5; N, 5.9; S, 4.5. Found: C, 58.8; H, 4.4;
Appendix A. Supplementary data
CCDC 817055, 817056 and 817057 contains the supplementary
crystallographic data for 1a, 1c and 3c. These data can be obtained
free of charge via http://www.ccdc.cam.ac.uk/conts/retriev-
ing.html, or from the Cambridge Crystallographic Data Centre, 12
Union Road, Cambridge CB2 1EZ, UK; fax: +44 1223 336 033; or
e-mail: deposit@ccdc.cam.ac.uk. Supplementary data associated
with this article can be found, in the online version, at
doi:10.1016/j.poly.2011.09.012.
N, 5.8; S, 4.3%. IR (cmꢀ1):
m
(N–H) 3464s;
m(C@N) 1567 m. 1H NMR
(CDCl3): d6.68 (dd, 1H, H2, 3JH2F = 10.6 Hz, 4JH2H4 = 2.8 Hz), 6.18 (td,
3
3
4
1H, H4, JH4F = 8.3 Hz, JH4H5 = 8.3 Hz, JH4H2 = 2.8 Hz), 6.10 (ddd,
1H, H5, JH5H4 = 8.3 Hz, JH5F = 6.5 Hz), 4.85 (q, 1H, NHMe, JNH–
3
4
3
2
H = 5.1 Hz), 3.25 (d, 2H, PCH2P, JHP = 9.2 Hz), 2.98 (d, 3H, NHCH3,
3JH–NH = 5.1 Hz), 2.30 (s, 3H, CH3C@N). 31P–{1H} NMR (CDCl3): d
2
2
25.0 (d, 1 P, PA, JPP = 75.1 Hz), ꢀ26.4 (d, 1 P, PB, JPP = 75.1 Hz).
Compounds 7b, 7c were synthesized following a similar
procedure.
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