Palladium(II) compounds with fluorinated pincer-type (SCS) ligands: X-ray structures

Article abstract of DOI:10.1002/ejic.200500818

Metathesis reactions employing lead fluorothiolates and C₆H ₄-1,3-(CH₂Br)₂ afford the corresponding pincer-type dithioether ligands C₆H₄-1,3-(CH ₂SR_f)₂ [R

Full text of DOI:10.1002/ejic.200500818

FULL PAPER
DOI: 10.1002/ejic.200500818
Palladium(II) Compounds with Fluorinated Pincer-Type (SCS) Ligands: X-ray
Structures of C6H4-1,3-(CH2SC6H4F-4)2 and [PdCl(SCS–Rf)] [Rf = C6H4F-2,
C6H4F-3, C6H4F-4, C6H4(CF3)-2, and C6H4(CF3)-4]
Ruy Cervantes,[a] Sandra Castillejos,[a] Stephen J. Loeb,[b] Luis Ortiz-Frade,[a]
Jorge Tiburcio,[b] and Hugo Torrens*[a]
Keywords: Fluorine / Sulfur / Pincer ligands / Thioether / Palladium compounds
Metathesis reactions employing lead fluorothiolates and
C6H4-1,3-(CH2Br)2 afford the corresponding pincer-type di-
thioether ligands C6H4-1,3-(CH2SRf)2 [Rf = C6H4F-2 (L1),
C6H4F-3 (L2), C6H4F-4 (L3), C6H4CF3-2 (L4), C6H4CF3-3 (L5),
and C6H4CF3-4 (L6)]. A series of PdII pincer-type complexes
[PdCl(κ3-Ln)], 1 to 6, were prepared and fully characterized.
The X-ray diffraction molecular structures of C6H4-1,3-
[CH2S(C6H4F-4)]2 (L3), [PdCl(SCS–C6H4F-2)] (1), [PdCl-
(SCS–C6H4F-3)] (2), [PdCl(SCS–C6H4F-4)] (3), [PdCl{SCS–
C6H4(CF3)-2}] (4), and [PdCl{SCS–C6H4(CF3)-4}] (6) are also
reported.
(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2006)
particular, fluorine-containing pincer-type complexes are
relatively rare.[21] The fluorous SCS pincer-type palladium
complex with a SCS–C6H4-p-C6F13 ligand has recently been
synthesized and shown to be catalytically active under both
microwave and thermal heating.[22] The fluorinated PCP
pincer-type complexes [RuCl{C6H3-2,6-[CH2P(C6F5)2]2}-
(PPh3)],[23a] [PdCl{C6H3-2,6-[CH2P(C6F5)2]2}], and [Pd-
(NCCH3){C6H3-2,6-[CH2P(C6F5)2]2}]BF4 have also re-
cently been described.[23b]
As part of our interest in fluorinated sulfur-containing
ligands,[24] we have synthesized a series of SCS pincer-type
ligands with several fluorinated substituents at the sulfur
atoms.[25] In this paper, we report on the synthesis and char-
acterization of the pincer-type dithioether ligands C6H4-
1,3-(CH2SRf)2 [Rf = C6H4F-2 (L1), C6H4F-3 (L2), C6H4F-
Introduction
Pincer-type palladacycles are one of the most popular
and well-investigated classes of cyclometalated com-
pounds.[1,2] They have found application in diverse areas
from efficient catalyst precursors[3] to molecular materials
for crystalline switches and sensors.[4] In particular, SCS
pincer-type palladium compounds have been widely studied
as catalyst precursors, either as low-molecular-weight or
PEG-supported polymers,[2a,5] for PdII-catalyzed Heck[6]
and Suzuki[2d,7] cross-coupling reactions.[8–10] SCS pincer-
type palladium compounds have also been the focus of
interesting structural and conformational studies such as
isomeric exchange[11] and dimer formation.[12] Macromolec-
ular and self-assembled supramolecular chemistry have also
profited from the useful properties of SCS pincer-type com-
pounds for the construction of polymetallic complexes,[13]
macrocycles,[14] large metallodendrimers,[15] functionalized
polymers,[16] mixed Pd–Au nanoparticles,[17] polypincer-
porphyrin compounds,[18] and supramolecular arrays of
palladium.[19]
4
(L3), C6H4(CF3)-2 (L4) C6H4(CF3)-3 (L5), and
C6H4(CF3)-4 (L6)] and the corresponding PdII complexes
[PdCl(Ln)], 1 to 6, and include the X-ray diffraction struc-
tures of C6H4-1,3-(CH2SC6H4F-4)2 (L3), [PdCl(SCS–
C6H4F-2)] (1), [PdCl(SCS–C6H4F-3)] (2), [PdCl(SCS–
C6H4F-4)] (3), [PdCl{SCS–C6H4(CF3)-2}] (4), and
[PdCl{SCS–C6H4(CF3)-4}] (6).
The possibility of fine tuning the steric and electronic
properties of the metal center by simply changing the donor
groups or their substituents is one of the features that
makes this anionic, terdentate, six-electron donor ligand so
flexible and amenable to a plethora of applications.[20] In
Results and Discussion
SCS Pincer-Type Ligands
[a] División de Estudios de Postgrado, Facultad de Química,
UNAM, Cd. Universitaria,
Lead fluorothiolates, Pb(SRf)2, react with C6H4-1,3-
(CH2Br)2 to give the corresponding dithioether compounds
C6H4-1,3-(CH2SRf)2 [Rf = C6H4F-2 (L1), C6H4F-3 (L2),
C6H4F-4 (L3), C6H4(CF3)-2 (L4), C6H4(CF3)-3 (L5), and
C6H4(CF3)-4 (L6)] as clear dense oils (L1, L2, L4, and L5)
04510 México D. F., México
Fax: +52-56223724
E-mail: Torrens@servidor.unam.mx
[b] Department of Chemistry & Biochemistry, University of Wind-
sor,
Windsor, Ontario N9B 3P4, Canada
1076
© 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Palladium() Compounds with Fluorinated Pincer-Type (SCS) Ligands
FULL PAPER
Scheme 1. Synthesis of dithioether compounds L1–L6.
or crystalline white solids (L3 and L6), in very good yields
(see Scheme 1).
The mass spectra of all compounds show the signals cor-
responding to the molecular ion [M]+ with significant inten-
1
sities (75–90%). The H NMR spectra of compounds L1–
L6 exhibit a singlet for the benzylic CH2 protons. All other
signals appear in the aromatic region as multiplets. The 13
C
NMR spectra show quartets for the carbon atoms of the
CF3 groups, whereas the signals for all aromatic carbon
atoms with fluorine atoms appear as doublets as a result of
their magnetic coupling with the fluorine nuclei. The re-
maining signals have been assigned with the aid of two-
dimensional HETCOR experiments. As expected, the 19F
NMR spectra for all compounds show only one signal. IR,
1H and 19F NMR spectroscopy as well as EI-MS data (re-
ported in the Experimental Section) confirm the identity of
each ligand.
Figure 2. ORTEP drawing of compound L3, view along the C9–
C11 axis.
Table 1. Selected bond lengths [Å] and angles [°] for compound
C6H4-1,3-(CH2SC6H4F-4)2 (L3).
Bond
Length
Atoms
Angle
S(1)–C(4)
S(1)–C(7)
C(9)–C(8)
C(8)–C(10)
C(10)–C(11)
C(4)–C(3)
C(4)–C(5)
C(5)–C(6)
C(6)–C(1)
C(1)–C(2)
C(3)–C(2)
F(1)–C(1)
1.770(3)
1.809(3)
1.389(3)
1.383(3)
1.376(3)
1.389(4)
1.379(3)
1.380(4)
1.355(4)
1.366(4)
1.372(4)
1.355(3)
C(4)–S(1)–C(7)
C(3)–C(4)–S(1)
C(5)–C(4)–S(1)
C(8)–C(7)–S(1)
C(9)–C(8)–C(7)
C(10)–C(8)–C(7)
C(5)–C(4)–C(3)
C(1)–C(6)–C(5)
C(1)–C(2)–C(3)
C(6)–C(1)–C(2)
F(1)–C(1)–C(2)
F(1)–C(1)–C(6)
C(10)–C(8)–C(9)
104.26(12)
116.3(2)
125.2(2)
106.84(17)
121.1(2)
120.2(2)
118.5(3)
119.1(3)
118.5(3)
122.2(3)
118.8(3)
119.0(3)
118.8(2)
The X-ray structure of C6H4-1,3-(CH2SC6H4F-4)2 (L3)
is shown in Figure 1 and Figure 2, and the principal bond
lengths and angles are reported in Table 1. The solid-state
structure analysis of compound L3 corresponds to the re-
1
sults obtained from H, 13C, and 19F NMR spectroscopy,
observed in solution.
Pincer-Type Palladacycles
In our experiments, the reaction of the highly fluorinated
pincer-type ligands C6H4-1,3-(CH2SC6F5)2 or C6H4-1,3-
[25]
(CH2SC6HF4-4)2
with either [PdCl2(NCCH3)2] or
[Pd(NCCH3)4](BF4)2 failed to produce the expected pallada-
cycle derivatives. SC6F5 or SC6HF4-4 are much poorer do-
nors than the corresponding protioaryl systems and, in con-
trast to phosphanes, they are not considered to be particu-
larly good π acceptors.[26] Both of these effects contribute
to a weaker S–Pd bond than the competing Pd–NCCH3
Figure 1. ORTEP drawing of compound C6H4-1,3-(CH2SC6H4F-
4)2 (L3).
In contrast with the structure of C6H4-1,3-(CH2SC6F5)2,[25] interactions and prevent the formation of the Pd pincer-
in which the SRf groups are positioned on opposite sides type compounds. This lack of reactivity emphasizes the im-
of, and almost parallel to, the central aromatic ring, the portance of sulfur coordination as a preliminary step to C–
molecular structure of L3 has a syn configuration where the Pd bond formation.
sulfur substituents point in the same direction as and are
In contrast, the reaction of ligands L1–L6 with
almost perpendicular to the central aromatic ring.
[PdCl2(NCCH3)2] yielded the corresponding SCS pallada-
Eur. J. Inorg. Chem. 2006, 1076–1083
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R. Cervantes, S. Castillejos, S. J. Loeb, L. Ortiz-Frade, J. Tiburcio, H. Torrens
FULL PAPER
Scheme 2. Synthesis of palladium compounds 1–6.
cycle compounds shown below as air-stable, yellow, crystal- tively, and selected bond lengths and angles are reported in
line solids. The yields are noticeably different for com- Table 2.
pounds bearing monofluorinated rings (1: 96, 2: 81, 3: 68%)
from those with the bulkier C6H4CF3 moiety (4: 79, 5: 36,
6: 44%), probably because they are influenced by steric fac-
tors (Scheme 2).
The 1H NMR spectra of compounds 1–6 in CD3CN
show a broad singlet for the CH2SRf protons in the δ Ϸ
4.2–4.7 ppm range, probably because of a combination of
syn–anti isomer exchange and the conformational intercon-
version of the PdII-containing five-membered rings.[27] The
signal for the proton at ca. 7 ppm (C1–H) is absent, indicat-
ing complete cyclopalladation. With the exception of com-
pound 4, for which the low solubility precluded its measure-
ment, the C1 shielding, as a result of cyclopalladation for
the rest of the complexes, is also diagnostic of palladation
at C1. The (δ13C1–H – δ13C1–Pd) values are as follows: 1
28.29; 2 30.74; 3 33.57; 5 30.37; and 6 30.91 ppm. Likewise,
the parameters defined as ∆Ln = δ13C1 – δ13C4 for the li-
gands and ∆n = δ13C1 – δ13C4 for the palladium complexes
have the following values: ∆L1 = 0.74, ∆1 = 34.08; ∆L2
=
0.57, ∆2 = 35.86; ∆L3 = 0.87, ∆3 = 37.09; ∆L5 = 0.63, ∆5 =
35.3; and ∆L6 = 0.44, ∆6 = 35.87 ppm.
19F{-1H} NMR spectra of compounds 1–3 and 4–6 exhi-
bit a single, sharp resonance in the fluoro-aromatic region
(–108.89, –113.69, –114.6 ppm) or in the CF3-aromatic re-
gion (–56.56, –62.99, –62.60 ppm), respectively. Thus, iso-
mers arising from substituent orientation relative to the
square plane are not detected, which suggests that, in these
complexes, sulfur inversion is either absent or faster than
the NMR time scale. Palladium complexes of related thio-
ethers exhibit relatively low energies for the process
involving the inversion of configuration at the sulfur atoms
(∆E Ϸ 50–70 kJmol–1), which is probably also true in these
cases.[28]
Figure 3. ORTEP drawing of compound [PdCl(SCS–C6H4F-2)] (1).
The Pd atoms are in slightly distorted square-planar en-
vironments: S(1)–Pd(1)–S(2), 1 171.94(6); 2 170.84(3); 3
170.28(2)° and Cl(1)–Pd(1)–C(1), 1 180.00(1); 2 177.83(10);
3 179.03(7)°. The bonding parameters of Pd are very similar
to those observed for the complexes [PdCl{2,6-C6H3-
(CH2StBu)2}],[29] Pd–S 2.308(2); Pd(1)–Cl(1) 2.406(3); and
Pd–C(1) 1.998(11) Å; [PdCl{2,3,5,6-C6H-(CH2StBu)4}],[19f]
Pd–S(1) 2.297(3); Pd(1)–S(2) 2.302(3); Pd(1)–Cl(1) 2.408(3);
Pd–C(1)
1.994(9) Å;
and
[Pd{4-(nBuO)-2,6-C6H2-
(CH2SPh)2}(NCCH3)]+,[30] Pd–S(1) 2.2992(8); Pd–S(2)
2.2961(9); Pd–C(1) 1.975(2) Å.
The C6H4F-2 and C6H4F-3 groups attached to the metal-
bound sulfur atoms in 1 and 2 are oriented in an anti fash-
ion with respect to the square plane; a common conforma-
Molecular Structures
An X-ray structural study of compounds 1–3 provided tion observed in these type of compounds,[19f,29–31] which
solid-state evidence verifying the solution results and con- allows for minimization of any steric repulsions between the
firming, for all cases, the terdentate-binding mode of the aromatic rings. In contrast, the C6H4F-4 groups attached
SCS ligands. ORTEP drawings of [PdCl(SCS–C6H4F-2)] to the metal-bound sulfur atoms in 3 are oriented in a syn
(1), [PdCl(SCS–C6H4F-3)] (2), and [PdCl(SCS–C6H4F-4)] fashion with respect to the square plane; this allows for
(3) are shown in Figure 3, Figure 4 and Figure 5, respec- maximization of intermolecular aromatic π-stacking inter-
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Palladium() Compounds with Fluorinated Pincer-Type (SCS) Ligands
FULL PAPER
actions between the metalated rings in adjacent molecules
at ca. 3.5 Å (see Figure 6). This positive interaction proba-
bly compensates any losses derived from steric repulsions
that arise as a result of the changing from an anti to a syn
conformation.
Figure 4. ORTEP drawing of compound [PdCl(SCS–C6H4F-3)] (2).
Figure 6. ORTEP drawing of compound 3 showing the aromatic π-
stacking interactions between adjacent molecules (hydrogen atoms
are omitted for clarity).
The X-ray diffraction molecular structure of compounds
[PdCl{SCS–C6H4(CF3)-2}] (4) and [PdCl{SCS–C6H4(CF3)-
4}] (6) are shown in Figure 7 and Figure 8, respectively and
selected bond lengths and angles are reported in Table 3.
Figure 5. ORTEP drawing of compound [PdCl(SCS–C6H4F-4)] (3).
Table 2. Selected bond lengths [Å] and angles [°] with estimated
standard deviations for complexes 1, 2, and 3.
Bond
1
2
3
Pd1–C1
Pd1–S1
Pd1–S2
Pd1–Cl1
S1–C7
S1–C8
S2–C14
S2–C15
1.994(7)
2.3021(10)
2.3021(10)
2.404(2)
1.836(5)
1.775(3)
1.836(5)
1.775(3)
1.968(4)
2.2913(9)
2.3040(9)
2.4284(8)
1.828(4)
1.786(4)
1.826(4)
1.787(4)
1.979(2)
2.2970(6)
2.2842(6)
2.3943(6)
1.820(2)
1.788(2)
1.837(2)
1.785(2)
Angle
C1–Pd1–Cl1
C1–Pd1–S1
C1–Pd1–S2
S1–Pd1–S2
C7–S1–C8
180.00(1)
85.97(3)
85.97(3)
171.94(6)
103.7(2)
103.7(2)
177.83(10)
85.28(11)
85.62(11)
170.84(3)
98.04(17)
101.30(17)
179.01(7)
85.37(7)
84.91(7)
170.28(2)
104.38(11)
103.41(11)
Figure 7. ORTEP drawing of compound [PdCl{SCS–C6H4(CF3)-
2}] (4).
In compounds 4 and 6, the Pd atoms are also in a slightly
distorted square-planar environment: S(1)–Pd(1)–S(2), 4
C14–S2–C15
Eur. J. Inorg. Chem. 2006, 1076–1083
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R. Cervantes, S. Castillejos, S. J. Loeb, L. Ortiz-Frade, J. Tiburcio, H. Torrens
FULL PAPER
Summary and Conclusions
Pincer-type ligands of the SCS class can be prepared with
partially fluorinated aromatic substituents. However, only
those with a single F or CF3 group will undergo facile pal-
ladation reactions to give the corresponding palladacycle.
When the number of F atoms is increased, the resulting
electronic effect on the S donor is such that coordination
to palladium is too weak to allow for metallation to occur.
The solid-state structures show no unusual steric effects
that would prevent these complexes from being used in a
variety of catalytic reactions. We are currently testing these
complexes as catalysts for the Suzuki coupling of aromatic
groups. The results showing the effect of these electron-
withdrawing substituted SCS pincers will be reported in due
course.
Experimental Section
General: All reactions were carried out under inert conditions using
conventional Schlenk glassware. The solvents were dried by using
established procedures and distilled under nitrogen immediately
prior to use. TLC (Merck, 2×5 cm2 Kieselgel 60 F254) was used
to monitor the progress of the reaction under study with hexane/
ethyl acetate (9:1) as the eluent. The IR spectra were measured with
a Nicolet Avatar FT-IR spectrometer. 1H-, 13C-, and 19F NMR
spectra were recorded with a Varian Unity Inova 300 spectrometer
operating at 300 MHz. Chemical shifts are relative to TMS δ = 0
(1H, 13C) and CFCl3 δ = 0 (19F) using CD3CN as the solvent.
Figure 8. ORTEP drawing of compound [PdCl{SCS–C6H4(CF3)-
4}] (6).
Electron impact mass spectra were recorded with
a Jeol
JMSSX102A mass spectrometer. Elemental analyses were deter-
mined using a Fisons EA1108 instrument. The starting material
1,3-bis(bromomethyl)benzene was obtained from Aldrich Chemical
Co. and used without further purification. C6H3-1,3-(CH2-
Table 3. Selected bond lengths [Å] and angles [°] with estimated
standard deviations for complexes 4 and 6.
SC6F5)2, C6H3-1,3-(CH2SC6HF4-4)2,[25] and Pb(SRf)2
(Rf =
[32]
C6H4F-2, C6H4F-3, and C6H4F-4) were prepared according to pub-
lished procedures.
Bond
4
6
Pd1–C1
Pd1–S1
Pd1–S2
Pd1–Cl1
S1–C7
S1–C8
S2–C15
S2–C16
1.983(3)
1.982(4)
Preparation of Compounds L1–L6: C6H4-1,3-(CH2SC6H4F-n)2 (L1–
L3) and C6H4-1,3-[CH2SC6H4(CF3)-n]2 (L4–L6).
2.3044(13)
2.2915(12)
2.3893(14)
1.830(3)
1.786(3)
1.830(3)
2.2767(13)
2.3195(13)
2.3929(13)
1.841(5)
1.787(4)
1.815(5)
In all reactions, stoichiometric quantities of reactants were used,
and since all preparations were similar, only a typical procedure is
described.
Pb(SC6H4F-n)2 or Pb[SC6H4(CF3)-n]2 (0.41 mmol) was added to
a mixture of 1,3-bis(bromomethyl)benzene (0.113 g, 0.41 mmol) in
acetonitrile (30 mL). The stirred mixture was maintained under re-
flux for 24 h. After this time, PbBr2 was filtered off, the solvent
was removed under vacuum, and the residue purified by column
chromatography (silica gel; hexane/ethyl acetate 9:1).
1.792(3)
1.795(5)
Angle
C1–Pd1–Cl1
C1–Pd1–S1
C1–Pd1–S2
S1–Pd1–S2
C7–S1–C8
178.46(7)
85.47(8)
86.11(8)
171.54(2)
101.41(12)
100.07(13)
176.82(13)
85.43(14)
85.38(14)
165.99(4)
101.4(2)
Spectroscopic parameters follow the numbering scheme shown in
the following diagram.
C15–S2–C16
102.8(2)
171.54(2); 6 165.99(4)° and Cl(1)–Pd(1)–C(1), 4 178.46(7);
6 176.82(13)°. The bonding parameters for Pd are compar-
able with those observed for complexes 1–3 and analogous
compounds.[19f,29–31] The C6H4(CF3)-n (n = 2 or 4) groups
attached to the metal-bound sulfur atoms are oriented in
an anti fashion with respect to the square plane, as is the
case for 1 and 2.
1080
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Eur. J. Inorg. Chem. 2006, 1076–1083

Palladium() Compounds with Fluorinated Pincer-Type (SCS) Ligands
C6H4-1,3-(CH2SC6H4F-2)2 (L1): Colorless oil; yield; 0.141 g, 92%.
FULL PAPER
4.21 (s, 4 H, 5-H), 7.26 (m, 3 H, 3-H, 4-H), 7.40 (m, 5 H, 1-H, 8-H,
10-H), 7.52 (m, 4 H, 7-H, 11-H) ppm. 13C{1H} NMR (75.36 MHz,
IR (KBr): ν = 3030, 2922, 1593, 1472, 1220, 1260 cm–1. EI-MS:
˜
=
m/z (%)
358 [M+] (90), 231 (100), 104 (45). 1H NMR CD3CN): δ = 37.3 (C-5), 129.0 (C-3), 129.9 (C-4), 130.4 (C-1),
(299.69 MHz, CD3CN): δ = 4.09 (s, 4 H, 5-H), 7.08 (m, 7 H, 3-H, 138.4 (C-2), 143.5 (C-6), 126.6 (q, 3JC,F = 7.9 Hz, C-8, C-10), 128.7
4-H, 8-H, 11-H), 7.22 (m, 5 H, 1-H, 9-H, 10-H) ppm. 13C{1H} (C-7, C-11), 125.5 (q, JC,F = 271.3 Hz, C-12), 127.9 (q, JC,F
=
=
2
2
NMR (75.36 MHz, CD3CN): δ = 37.5 (C-5), 116.5 (d, JC,F
22.7 Hz, C-8), 123.7 (d, JC,F = 17.7 Hz, C-6), 125.8 (d, JC,F
3.5 Hz, C-11), 128.8 (C-3), 129.6 (C-4), 129.8 (d, JC,F = 8.0 Hz,
C-9), 130.3 (C-1), 133.2 (d, 4JC,F = 2.9 Hz, C-10), 138.8 (C-2), 162.1
(d, JC,F = 242.6 Hz, C-7) ppm. 19F NMR (281.96 MHz, CD3CN):
=
=
32.3 Hz, C-9) ppm. 19F NMR (281.96 MHz, CD3CN):
δ
–62.60 ppm.
2
3
3
General Procedure for the Preparation of Palladium(II) Complexes
1–6: Dichloropalladium() (0.216 g, 1.22 mmol) in acetonitrile
(25 mL) was heated under reflux for 1 h. Silver tetrafluoroborate
(0.495 g, 2.54 mmol) was added to this solution. Silver chloride was
separated from the suspension by filtration through Celite. The li-
gand (L1–L6) (0.435 g, 1.22 mmol) was dissolved in warm acetoni-
trile (10 mL) and added to the filtrate. The solution immediately
3
4
5
4
δ = –108.89 (m, JF,H = 9.59, JF,H = 6.99, JF,H = 4.82, JF,H
0.13 Hz) ppm.
=
C6H4-1,3-(CH2SC6H4F-3)2 (L2): Colorless oil; yield: 0.138 g, 90%.
IR (KBr): ν = 3060, 2923, 1598, 1473, 1263, 1215 cm–1. EI-MS:
˜
m/z (%)
(299.69 MHz, CD3CN): δ = 4.15 (s, 4 H, 5-H), 6.90 (m, 2 H, 9-H), mixture turned yellow, and excess NaCl (0.189 g, 3.23 mmol) was
7.05 (m, 4 H, 7-H, 11-H), 7.35 (m, 6 H, 1-H, 3-H, 4-H, 10-H) ppm. added. The suspension was stirred overnight. The yellow precipi-
13C{1H} NMR (75.4 MHz, CD3CN): δ = 38.1 (C-5), 113.8 (d, 2JC,F tate was filtered off and washed three times with water and two
=
358 [M+] (75), 231 (100), 104 (65). 1H NMR turned orange and was heated under reflux for 4 h. The reaction
2
4
= 21.5 Hz, C-9), 116.2 (d, JC,F = 23.1 Hz, C-7), 125.5 (d, JC,F
=
times with ethanol. The products were obtained as yellow powders.
3.0 Hz, C-11), 128.9 (C-3), 129.7 (C-4), 130.3 (C-1), 131.6 (d, 3JC,F
[PdCl{C6H3-1,3-(CH2SC6H4F-2)2}] (1): Yellow crystals; yield:
3
= 8.5 Hz, C-10), 138.7 (C-2), 140.0 (d, JC,F = 8.0 Hz, C-6), 163.8
0.583 g, 96%. M.p. 187 °C. IR (KBr): ν = 750, 1470, 1449, 1221,
˜
(d, JC,F = 244.6 Hz, C-8) ppm. 19F NMR (281.96 MHz, CD3CN):
1262, 724, 818, 1061, 1029, 2900, 2976, 3046 cm–1. EI-MS: m/z (%)
= 500 [M + 1]+ (5), 463 (60), 391 (40). 1H NMR (299.69 MHz,
CDCl3): δ = 4.65 (s, 4 H, 5-H), 7.18 (m, 4 H, 8-H, 11-H), 6.97 (m,
3
3
4
5
δ = –113.69 (m, JF,H = 9.54, JF,H = 6.16, JF,H = 9.00, JF,H
=
0.96 Hz) ppm.
C6H4-1,3-(CH2SC6H4F-4)2 (L3): White microcrystalline powder; 3 H, 3-H, 4-H), 7.45 (m, 2 H, 9-H), 8.28 (m, 2 H, 10-H) ppm.
yield: 0.145 g, 95%. M.p. 51–52 °C. IR (KBr): ν = 2918, 1595,
13C{1H} NMR (75.36 MHz, CDCl3): δ = 52.1 (C-5), 116.5 (d, 2JC,F
1490, 1239, 822 cm–1. EI-MS: m/z (%) = 358 [M+] (85), 231 (100), = 21.7 Hz, C-8), 119.0 (d, 2JC,F = 16.1 Hz, C-6), 122.2 (C-3), 123.0
˜
1
3
3
104 (45). H NMR (299.69 MHz, CD3CN): δ = 4.04 (s, 4 H, 5-H),
(d, JC,F = 8.2 Hz, C-9), 125.1 (d, JC,F = 3.8 Hz, C-11), 125.2 (C-
7.00 (m, 4 H, 8-H, 10-H), 7.13 (m, 4 H, 1-H, 3-H, 4-H), 7.28 (m, 4), 136.5 (C-10), 148.4 (C-2), 159.2 (C-1), 160.8 (d, JC,F = 251.1 Hz,
4 H, 7-H, 11-H) ppm. 13C{1H} NMR (75.36 MHz, CD3CN): δ =
39.8 (C-5), 116.9 (d, 2JC,F = 21.7 Hz, C-8, C-10), 128.7 (C-3), 129.5
C-7) ppm. 19F NMR (281.96 MHz, CDCl3): δ = –106.31 ppm.
C20H15S2F2PdCl (499.3): calcd. C 48.11, H 3.03, S 12.84; found: C
48.30, H 3.36, S 13.01.
4
3
(C-1), 130.4 (C-4), 132.1 (d, JC,F = 2.8 Hz, C-6), 133.7 (d, JC,F
=
8.0 Hz, C-7, C-11), 139.1 (C-2), 162.8 (d, JC,F = 244.7 Hz, C-
[PdCl{C6H3-1,3-(CH2SC6H4F-3)2}] (2): Yellow crystals; yield:
4
9) ppm. 19F NMR (281.96 MHz, CD3CN): δ = –114.6 (m, JF,H
=
0.492 g, 81%. M.p. 165 °C. IR (KBr): ν = 727, 1472, 1214, 873,
˜
5.21, 3JF,H = 9.02 Hz) ppm. C20H16F2S2 (358.5): calcd. C 67.02, H,
1579, 749, 777, 1420, 674, 1264, 2922, 3053 cm–1. EI-MS: m/z (%)
4.50, S 17.86; found C 66.94, H 4.45, S 17.23.
1
= 500 [M + 1]+ (5), 463 (70). H NMR (299.69 MHz, CDCl3): δ =
C6H4-1,3-[CH2SC6H4(CF3)-2]2 (L4): Yellowish oil; yield: 0.158 g, 4.62 (s, 4 H, 5-H), 7.04 (m, 5 H, 9-H, 3-H, 4-H), 7.34 (m, 2 H, 10-
80.4%. IR (KBr): ν = 1312, 1112, 1172, 1034, 760, 1258, 1440,
H), 7.51 (m, 2 H, 7-H), 7.61 (m, 2 H, 11-H) ppm. 13C{1H} NMR
˜
2
1592 cm–1. EI-MS: m/z (%) = 458 [M+] (40), 281 (100), 104 (30).
1H NMR (299.69 MHz, CD3CN): δ = 4.20 (s, 4 H, 5-H), 7.22 (m,
3 H, 3-H, 4-H), 7.32 (m, 3 H, 1-H, 9-H), 7.48 (m, 4 H, 10-H, 11-
(75.36 MHz, CDCl3): δ = 51.2 (C-5), 117.0 (d, JC,F = 21.2 Hz, C-
9), 118.0 (d, 2JC,F = 24.2 Hz, C-7), 122.5 (C-3), 125.19 (C-4), 126.9
3
(d, 4JC,F = 3.0 Hz, C-11), 131.1 (d, JC,F = 8.1 Hz, C-10), 133.7 (d,
H), 7.66 (m, 2 H, 8-H) ppm. 13C{1H} NMR (75.36 MHz, CD3CN): 3JC,F = 8.0 Hz, C-6), 149.0 (C-2), 161.0 (C-1), 162. 5 (d, JC,F
=
=
3
δ = 38.8 (C-5), 127.3 (C-9), 127.8 (q, JC,F = 5.8 Hz, C-8), 129.1 251.6 Hz, C-8) ppm. 19F NMR (281.96 MHz, CDCl3):
δ
(C-3), 129.8 (C-4), 130.6 (C-1), 132.2 (C-11), 133.5 (C-10), 136.6
–109.8 ppm. C20H15S2F2PdCl (499.3): calcd. C 48.11, H 3.03, S
12.84; found C 48.05, H 3.17, S 13.01.
(C-6), 138.2 (C-2), 129.6 (q, 2JC,F = 30.2 Hz, C-7), 125.2 (q, JC,F
=
273.4 Hz, C-12) ppm. 19F NMR (281.96 MHz, CD3CN): δ =
–56.56 ppm.
[PdCl{C6H3-1,3-(CH2SC6H4F-4)2}] (3): Yellow crystals; yield:
0.413 g, 68%. M.p. 198 °C. IR (KBr): ν = 1489, 1218, 1153, 826,
˜
C6H4-1,3-[CH2SC6H4(CF3)-3]2 (L5): Yellowish oil; yield: 816, 843, 1415, 772, 3058, 298, 3085 cm–1. EI-MS: m/z (%) = 500
0.155 g,79.3%. IR (KBr): ν = 1322, 1124, 1165, 1072, 695, 793, [M + 1]+ (10), 463 (100). 1H NMR (299.69 MHz, CDCl3): δ = 4.67
˜
711, 1425 cm–1. EI-MS: m/z (%) = 458 [M+] (20), 281 (75), 104 (70).
1H NMR (299.69 MHz, CD3CN): δ = 4.18 (s, 4 H, 5-H), 7.28 (m,
(s, 4 H, 5-H), 7.00 (m, 3 H, 3-H, 4-H), 7.186 (m, 4 H, 8-H, 10-H),
7.94 (m, 4 H, 7-H, 11-H) ppm. 13C{1H} NMR (75.36 MHz,
3 H, 3-H, 4-H), 7.33 (m, 1 H, 1-H), 7.48 (m, 8 H, 7-H, 9-H, 10-H, CDCl3): δ = 53.0 (C-5), 117.6 (d, 2JC,F = 22.8 Hz, C-8, C-10), 123.5
11-H) ppm. 13C{1H} NMR (75.36 MHz, CD3CN): δ = 38.1 (C-5),
123.7 (q, 3JC,F = 4.0 Hz, C-9), 126.1 (q, 3JC,F = 3.7 Hz, C-7), 128.9
(C-3), 129.7 (C-4), 130.8 (C-1), 133.7 (C-10), 133.4 (C-11), 138.6
(C-3), 126.0 (C-4), 129.0 (d, JC,F = 3.0 Hz, C-6), 135.3 (d, JC,F
9.1 Hz, C-7, C-11), 150.6 (C-2), 163.1 (C-1), 164.5 (d, JC,F
=
=
=
4
3
248.1 Hz, C-9) ppm. 19F NMR (281.96 MHz, CDCl3):
δ
(C-2), 139.1 (C-6), 131.5 (q, 2JC,F = 32.3 Hz, C-8), 125.1 (q, JC,F
=
–107.1 ppm. C20H15S2F2PdCl (499.3): calcd. C 48.11, H 3.03, S
12.84; found C 44.90, H 3.03, S 12.27.
272.4 Hz, C-12) ppm. 19F NMR (281.96 MHz, CD3CN): δ =
–62.99 ppm.
[PdCl{SCS–C6H4(CF3)-2}] (4): Yellow crystals; yield: 0.450 g, 79%.
C6H4-1,3-[CH2SC6H4(CF3)-4]2 (L6): White microcrystalline pow-
M.p. 130 °C (dec). IR (KBr): ν = 1310, 1181, 1117, 1029, 770, 1092,
˜
der; yield: 0.166 g, 85%. M.p. 61–63 °C. IR (KBr): ν = 1327, 1121,
1265 cm–1. 1H NMR (299.69 MHz, CDCl3): δ = 4.54 (s, 4 H, 5-H),
˜
1095, 1063, 1164, 1605, 823, 1013 cm–1. EI-MS: m/z (%) = 458 [M+] 7.03 (m, 3 H, 3-H, 4-H), 7.69 (m, 6 H, 8-H, 9-H, 11-H), 8.75 (m,
(30), 281 (100), 104 (25). 1H NMR (299.69 MHz, CD3CN): δ =
2 H, 10-H) ppm. 13C{1H} NMR (75.36 MHz, CDCl3): δ = 55.7 (C-
Eur. J. Inorg. Chem. 2006, 1076–1083
© 2006 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
1081

R. Cervantes, S. Castillejos, S. J. Loeb, L. Ortiz-Frade, J. Tiburcio, H. Torrens
FULL PAPER
Table 4. Crystallographic data, solution and refinement parameters for single crystal structure determinations of compounds L3, 1, 2, 3,
4, and 6.
L3
1
2
3
4
6
Formula
Formula mass
Crystal system
Space group
T [K]
a [Å]
b [Å]
c [Å]
α [°]
β [°]
C20H16F2S2
358.47
orthorhombic
Pnma
C20H15ClF2PdS2 C20H15ClF2PdS2 C20H15ClF2PdS2 C22H15ClF6PdS2 C22H15ClF6PdS2
499.29
orthorhombic
Fdd2
499.29
499.29
monoclinic
P21/n
599.31
monoclinic
P21/c
599.31
monoclinic
P21/c
triclinic
¯
P1
298(2)
298(2)
173(2)
173(2)
173(2)
173(2)
6.868(5)
33.026(5)
7.623(5)
35.219(5)
9.817(5)
10.920(5)
8.5669(5)
9.5228(6)
11.8512(7)
96.153(1)
100.303(1)
103.385(1)
914.2(1)
2
9.2552(11)
18.417(2)
11.2976(13)
17.173(12)
8.809(6)
14.689(10)
8.371(3)
27.069(8)
9.899(3)
103.993(1)
98.143(7)
107.945(3)
γ [°]
V [Å3]
1729.1(2)
8
1.377
0.325
3154
2331
3776(3)
8
1868.6(4)
4
2200(3)
4
2134.0(1)
4
Z
Dcalcd. [gcm–3]
µ [mm–1]
reflections collected
unique reflections
1.757
1.365
1.814
1.410
1.775
1.380
1.810
1.214
1.865
1.251
1813
1580
7260
3201
17746
3291
19198
3880
20216
3752
R1/R2w [I Ͼ 2σ(I)][a] 0.0532/0.0978
0.0270/0.0604
0.0322/0.0622
1.066
0.0329/0.0971
0.0335/0.0976
1.089
0.0207/0.0595
0.245/0.0619
1.026
0.0246/0.0712
0.0275/0.0770
1.085
0.0442/0.1057
0.0474/0.1078
1.088
R1/R2w (all data)[b]
GoF on F2
0.1391/0.1229
0.954
Parameters/restrains
Min./max. residual
density [eÅ–3]
112/0
0.275/0.259
120/1
–0.390/0.376
235/0
–1.13/1.41
235/0
–0.22/0.40
289/0
–0.52/0.55
289/0
–1.31/1.66
[a] R1 = Σ|Fo| – |Fc| / Σ|Fo|;. [b] R2w = {Σ[w(Fo – Fc ) ] / Σ[w(Fo2)2]}1/2, where w = q[σ2(Fo2) + (aP)2 + bP]–1.
2
2 2
5), 122.4 (C-3), 125.0 (C-4), 125.6 (C-9), 126.9 (C-8), 131.3 (C-11), Kα X-ray radiation (λ = 0.71073 Å). X-ray diffraction data for com-
133.5 (C-10), 147.8 (C-2) ppm. 19F NMR (281.96 MHz, CDCl3): δ pounds 2, 3, 4, and 6 were collected at 173 K with a Bruker APEX
= –59.09 ppm.
CCD single crystal diffractometer with Mo-Kα X-ray radiation (λ
= 0.71073 Å). The structures were solved by direct methods using
SHELXS 97–2.[33] Least-squares refinement based on F2 was car-
ried out by a full-matrix method with SHELXL 97–2.[33] All non-
hydrogen atoms were refined with anisotropic thermal parameters.
The location of hydrogen atoms was generated geometrically and
included in the refinement with an isotropic fixed thermal param-
eter using a “riding” model. Neutral atom scattering factors and
anomalous dispersion corrections were taken from International
Tables for Crystallography.[34] Molecular structure drawings were
generated using ORTEP3 for Windows.[35]
[PdCl{SCS–C6H4(CF3)-3}] (5): Yellow crystals; yield: 0.205 g, 36%.
M.p. 194 °C. IR (KBr): ν = 1320, 1122, 1176, 1103, 1072, 692, 797,
˜
769 cm–1. FAB(+)-MS: m/z (%) = 598 [M+] (2), 563 (100), 417 (10),
385 (8), 279 (20), 135 (10). 1H NMR (299.69 MHz, CDCl3): δ =
4.67 (s, 4 H, 5-H), 7.05 (m, 3 H, 3-H, 4-H), 7.53 (t, 3JH,H = 7.8 Hz,
3
2 H, 10-H), 7.65 (d, JH,H = 7.8 Hz, 2 H, 9-H), 8.00 (s, 2 H, 7-H),
3
8.13 (d, JH,H
= 8.1 Hz, 2
H, 11-H) ppm. 13C{1H} NMR
(75.36 MHz, CDCl3): δ = 51.6 (C-5), 122.6 (C-3), 123.2 (q, JC,F
=
3
273.2 Hz, C-12), 125.4 (C-4), 126.8 (q, JC,F = 3.7 Hz, C-9), 127.5
3
2
(q, JC,F = 3.7 Hz, C-7), 130.3 (C-10), 132.0 (q, JC,F = 33.2 Hz,
C-8), 133.3 (C-6), 135.2 (C-11), 148.6 (C-2), 160.7 (C-1) ppm. 19F
NMR (281.96 MHz, CDCl3): δ = –63.16 ppm. C22H15F6S2PdCl
(599.3): calcd. C 44.09, H 2.52, S 10.7; found C 43.80, H 2.72, S
11.28.
CCDC-251029 (L3), -251028 (1), -254754 (2), -281816 (3), -281832
(4), and -281831 (6) 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.
[PdCl{SCS–C6H4(CF3)-4}] (6): Yellow crystals; yield: 0.251 g, 44%.
M.p. 230 °C. IR (KBr): ν = 1320, 1123, 1061, 1169, 1085, 1011,
˜
838, 1604 cm–1. FAB(+)-MS: m/z (%) = 598 [M+] (2), 563 (100), 417
Acknowledgments
(10), 385 (8), 279 (25), 135 (10). 1H NMR (299.69 MHz, CDCl3): δ
3
= 4.66 (s, 4 H, 5-H), 7.07 (m, 3 H, 3-H, 3-H), 7.62 (d, JH,H
=
3
This work was supported by the CONACYT (Project 44494-Q) and
DGAPA-UNAM (Project IN119305).
8.4 Hz, 4 H, 8-H, 10-H), 7.91 (d, JH,H = 8.1 Hz, 4 H, 7-H7, 11-
H) ppm. 13C{1H} NMR (75.36 MHz, CDCl3): δ = 50.3 (C-5), 122.7
(C-3), 123.4 (q, JC,F = 270.8 Hz, C-12), 125.4 (C-4), 126.6 (q, 3JC,F
= 3.6 Hz, C-10, C-8), 128.8 (C-6), 130.8 (C-7, C-11), 131.6 (q, 2JC,F
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Received: September 15, 2005
Published Online: January 19, 2006
Eur. J. Inorg. Chem. 2006, 1076–1083
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