Palladium and molybdenum complexes of the heteroleptic organostannylene[2, 6-(Me2NCH2)2C6H3]SnCl

Article abstract of DOI:10.1021/om900166d

The synthesis and molecular structures are reported for the transition metal heteroleptic organo-stannylene complexes {[2,6-(Me₂NCH ₂)₂C₆H₃]SnCl}(C₅H ₅)(CO)₂MoCl (6) and {[2,6-(Me₂NC-H ₂)₂C₆H₃]Sn(OAc)}Pd(Cl)[2-(Me ₂NCH₂)C₆H₄] (7). It is shown that the intramolecularly coordinated heteroleptic organostannylene [2,6-(Me ₂NCH₂)₂C₆H₃]SnCl undergoes a redox-type reaction with Pd(PPh₃)₄ to give cis-[2,6-(Me₂NCH₂)₂C₆H ₃]SnCl}₂PdCl₂.

Full text of DOI:10.1021/om900166d

4778 Organometallics 2009, 28, 4778–4782
DOI: 10.1021/om900166d
Palladium and Molybdenum Complexes of the Heteroleptic
Organostannylene [2,6-(Me2NCH2)2C6H3]SnCl
,†
Jana Martincova, Roman Jambor,* Markus Schurmann, Klaus Jurkschat,*
‡
,‡
ꢀ †
€
§
^
ꢁ
Jan Honzıcek, and Filipe A. Almeida Paz
´
†
ꢁ
Department of General and Inorganic Chemistry, University of Pardubice, nam. Cs. legiı 565, CZ-532 10,
Pardubice, Czech Republic, Lehrstuhl fu€r Anorganische Chemie II der Technischen Universitat, D-44227
ꢀ
´
‡
€
§
´
ꢀ
Dortmund, Germany, Instituto de Tecnologia Quımica e Biologica da Universidade Nova de Lisboa,
Avenida da Repuꢀblica, EAN, 2780-157, Oeiras, Portugal, and ^Department of Chemistry, University of
Aveiro, CICECO, 3810-193 Aveiro, Portugal
Received March 2, 2009
The synthesis and molecular structures are reported for the transition metal heteroleptic organo-
stannylene complexes {[2,6-(Me2NCH2)2C6H3]SnCl}(C5H5)(CO)2MoCl (6) and {[2,6-(Me2NC-
H2)2C6H3]Sn(OAc)}Pd(Cl)[2-(Me2NCH2)C6H4] (7). It is shown that the intramolecularly coordi-
nated heteroleptic organostannylene [2,6-(Me2NCH2)2C6H3]SnCl undergoes a redox-type reaction
with Pd(PPh3)4 to give cis-[2,6-(Me2NCH2)2C6H3]SnCl}2PdCl2.
Introduction
prior to 2008.2,5 The latest studies showed that anionic
main group element donors such as (SnB11H11)- or [MeSi-
{SiMe2N(aryl)}3Sn]- are also able to form stable TM-Sn-
(II) complexes.6
An alternative to the sterically demanding bulky substit-
uents used in the kinetic stabilization of organostannylenes is
the use of so-called built-in ligands that contain side chain
substituents bearing nitrogen7 or oxygen8 donor atoms. In
The chemistry of transition metal (TM) complexes con-
taining stannylene ligands has been an active research area
during the last two decades since they appear to be catalytic
reagents for several reactions, depending on the type of
transition metal involved.1 The most common way to pre-
pare such complexes is by reacting a TM-Cl complex with a
stannylene SnR2 (where R is an organic or inorganic sub-
stituent). In such reactions the stannylenes may behave as a
two-electron ligand,2 may insert into the TM-Cl bond,3 or
may act as a reducing agent.4 Although examples for when
the Sn(II) atom behaves as a two-electron σ donor (e.g., as a
tertiary phosphine analogue) are known, only complexes of
homoleptic stannylenes of the type R2Sn or tin(II) amides
Sn(NR2)2 with sterically demanding R groups were reported
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*Corresponding authors. (R.J.) Fax: þ 420 466037068. E-mail:
roman.jambor@upce.cz. (K.J.) Fax: þ49 231 755 504. E-mail: klaus.
jurkschat@uni-dortmund.de.
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Chem. Rev. 1995, 95, 2485. (d) Parinello, G.; Stille, J. K. J. Am. Chem. Soc.
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pubs.acs.org/Organometallics
Published on Web 07/24/2009
2009 American Chemical Society

Article
Organometallics, Vol. 28, No. 16, 2009 4779
Chart 1
Scheme 1
such functionally substituted organostannylenes the Lewis
base character of the Sn(II) atom is increased as a result of
the intramolecular donorfSn coordination. Subsequently,
this should increase its ability to form complexes with
transition metal species that are Lewis acids. Heteroleptic
organostannylenes of the general formula (Y,C,Y)SnCl,
where Y,C,Y refers to a pincer-type ligand, are potential
candidates in this field.
Despite the fact that the organostannylene [2,6-(Me2-
NCH2)2C6H3]SnCl (1) has been known for a long time,
investigation of its reactivity is scarce and limited to oxidative
additions.7b,7c Recently we reported reactions of compound 1
and the related heteroleptic organostannylene {4-tBu-2,6-[P-
(O)(O-iPr)2]2C6H2}SnCl (2) with selected Pd(II) complexes to
give new complexes (3-5) where the heteroleptic organostan-
nylenes 1 and 2 behave as two-electron ligands (Chart 1).9
Extending the reactivity studies toward other transition
metal complexes, we report here the reactions of 1 with
Pd(PPh3)4 and [Mo(CO)2(CH3CN)2Cp]þBF4- to give cis-[2,-
6-(Me2NCH2)2C6H3]SnCl}2PdCl2 and {[2,6-(Me2NCH2)2-
C6H3]SnCl}(C5H5)(CO)2MoCl, respectively. Also reported
is the preparation of {[2,6-(Me2NCH2)2C6H3]Sn(OAc)}Pd-
(Cl)[2-(Me2NCH2)C6H4]. All compounds were characterized
by 1H, 13C, and 119Sn NMR spectroscopy, elemental analysis,
and single-crystal X-ray diffraction analysis.
The reaction shown in Scheme 1 appears to be a redox-type
reaction. In addition to the oxidation product 3 there must be
a reduction product, which is very likely the heavy acetylene
analogue RSnSnR (R=2,6-(Me2NCH2)2C6H311a). Unfortu-
nately, due to its instability,11a we were unable to isolate this
product from the corresponding reaction mixture.
The reaction of organostannylene 1 with bis-acetonitrile
dicarbonyl cyclopendadienyl molybdenium tetrafluorobo-
rate, [Mo(CO)2Cp(CH3CN)2]þBF4-,11b provided 2,6-(Me2-
NCH2)2C6H3(Cl)SnMo(CO)2CpCl (6) as crystalline material
and some rather poorly soluble amorphous white precipitate
(Scheme 2).
Compound 6 is the result of the simultaneous replace-
ment of acetonitrile, CH3CN, by the organostannylene 1
and chloride ion transfer from another molar equivalent of
1. Consequently the organostannylenium salt [2,6-(Me2-
NCH2)2C6H3]SnþBF4- must also have formed in this reac-
tion, but so far we were unable to unambiguously identify it.
Some support for its existence stems from elemental analy-
sis (see Experimental Section), 1H NMR spectroscopy, and
an electrospray ionization mass spectrum of the white
precipitate. The latter shows, in the positive mode, a mass
cluster centered at m/z 193 ([1,5-(Me2NCH2)2C6H4 H]þ)
and, in the negative mode, the presence of tetrafluoroborate
Results and Discussion
The reaction of compound 1 with tetrakis(triphenyl-
phosphine)palladium, Pd(PPh3)4, gave, regardless of the stoichio-
metry (1:1 to 1:6), a yellow solid precipitate, which was identified
as cis-[2,6-(Me2NCH2)2C6H3]SnCl}2PdCl2 (3)9 (Scheme 1).
ꢀ
ꢀ
ꢁ ꢁ
(9) (a) Martincova, J.; Dostal, L.; Ruzicka, A.; Taraba, J.; Jambor, R.
Organometallics 2007, 26, 4102. (b) Deaky, V.; Henn, M.; Sch€urmann, M.;
anion, BF-4 (m/z = 87), whereas the H NMR (CD3CN)
1
€
Jurkschat, K. 13th Vortragstagung der Wohler-Vereinigung der GDCh,
spectrum of a solution of the white precipitate from which
insoluble material had been filtered displayed resonances at
δ 7.56, 7.97 (aromatic protons), 4.27 (NCH2), and 2.75
(NCH3). These signals correspond to 1,5-(Me2NCH2)2-
C6H4, as evidenced by addition of an authentic sample.
Apparently, under the experimental conditions employed,
[2,6-(Me2NCH2)2C6H3]SnþBF-4 is not stable and easily
hydrolyzes.
September 18-19, 2006, RWTH Aachen, Germany, Book of Abstracts,
p 078.
(10) (a) Ferguson, G.; McCrindle, R.; McAlles, A. J.; Parvez, M. Acta
Crytallogr., Sect. B: Struct. Crystallogr. Cryst. Chem. 1982, 38, 2679. (b)
Kitano, Y.; Kinoshita, Y.; Nakanuta, R.; Ashida, T. Acta Crytallogr., Sect.
C: Cryst. Struct. Commun. 1983, 39, 1015.
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(11) (a) Jambor, R.; Kasna, B.; Kirschner, K. N.; Schurmann, M.;
Jurkschat, K. Angew. Chem., Int. Ed. 2008, 47, 1650. (b) Pereira, C. C. L.;
Braga, S. S.; Almeida Paz, F. A.; Pillinger, M.; Klinowski, J.; Goncalves, I. S.
Eur. J. Inorg. Chem. 2006, 4278.

ꢀ
Martincova et al.
4780 Organometallics, Vol. 28, No. 16, 2009
Scheme 2
The molecular structure of the molybdenum complex 6 is
shown in Figure 1, and selected bond distances and bond
angles are listed in the caption.
The 1H NMR spectrum of compound 6 showed, in addi-
tion to a singlet at δ 5.51 (Cp protons) and signals at δ 7.05
and 7.26 (aromatic protons), an AB-type resonance at δ 3.79
for the NCH2 and a singlet resonance at δ 2.54 for the NCH3
protons. This indicates that a dynamic process takes place,
but this was not investigated further. The 119Sn NMR
spectrum displayed a signal at δ 105, which is low-frequency
shifted with respect to the noncoordinated organostannylene
ligand (δ 157).7c The 13C NMR spectrum (δ(13C(CO))
at 266.7) together with IR spectroscopy ((CO) at 1946 and
1860 cm-1) proved the presence of CO groups in 6.
The compounds shown in Chart 1, as well as compound 6,
contain both Sn-Cl and TM-Cl bonds, which invokes the
question concerning the reactivity of these functionalities
toward nucleophiles. However, attempts at isolating pure
products from the reaction of the organostannylene palladium
complex 3 with silver acetate, AgOAc, were unsuccessful. In
contrast, the reaction of the organostannylene complex
[2,6-(Me2NCH2)2C6H3SnCl][2-(Me2NCH2)C6H4]PdCl (4),
which contains both a N,C,N- and a C,N-coordinating ligand,
with AgOAc gave, under exclusive Sn-Cl substitution, the
monoacetate-substituted complex [2,6-(Me2NCH2)2C6H3-
SnOAc][2-(Me2NCH2)C6H4]PdCl (7) (eq 1).
The unit cell contains two independent molecules that are
linked in a head-to-tail fashion by intermolecular Cl(1) H-
(23) and Cl(3) H(3) interactions with distances of 2.769(2)
3 3 3
3 3 3
and 2.762(2) A, respectively (see Supporting Information,
Figure S1). The geometric parameters of the two molecules
are rather similar, and consequently only the parameters of
one molecule are given in Figure 1. The structure is based on
the “four-legged piano stool motif”, which is typical for
compounds of the CpMoL4 type.12 The Mo(1)-Cl(1) dis-
tance of 2.521(2) A is shorter in comparison to the corres-
ponding distance reported for other “four-legged piano
stool”-type MoII complexes (e.g., 2.526(2) A in CpMoCl-
(triphos),13a 2.541(5) A in CpMoCl(CO)(dppe),13b and 2.542
(9) A in CpMoCl(CO)313c). The two Mo-C(O) bond lengths
of 1.955(9) and 1.973(8) A are comparable to those found in
CpMoI(CO)2(PBu3) (1.94(6) A) and CpMo(COCH3)(CO)2-
(PPh3) (1.951(13) A),14 but shorter than the average distance
in other compounds with weaker donating ancillary ligands
(e.g., 2.003(34) A in (C5H4Me)MoI(CO)2[P(OMe)3] and
2.091(14) A in CpMoBr(CO)2(PPh3)).15 The Sn(1)-Mo(1)
bond distance is 2.7195(9) A, which is shorter than the
Mo(II)-Sn(II) distance in (Cp)(CO)3MoSnC6H3-2,6-Mes2
(2.9045(10) A)16 and the Mo(0)-Sn(II) distance in [(OC)5-
ModSnRR0] (R = 2,4,6-tBu3C6H2, R0 = CH2C(CH3)2-3,-
5-tBu2C6H2, 2.756(1) A17). This hints at the strong donor
capacity of organostannylene 1. The Sn(1) atom is five-
coordinate and exhibits a distorted square-pyramidal con-
figuration with the N(1), N(2), C(8), and Mo(1) atoms
located in the equatorial positions and the Cl(2) atom in
the axial position, respectively. The intramolecular Sn(1)-
N(1), Sn(1)-N(2), Sn(1)-Cl(2), and Sn(1)-C(8) distances
are 2.494(6), 2.567(7), 2.452(2), and 2.120(10) A, respectively.
These distances are similar to the corresponding ones reported
for the parent organostannylene 1(2.525(8), 2.602(8), 2.488(3),
and 2.158(8) A).7c Notably, the Cl(1) atom approaches the
Sn(1) atom opposite the Cl(2) atom at a distance of 2.972(2) A,
which is shorter than the sum of the van der Waals radii of tin
(2.20 A) and chlorine (1.70-1.90 A).
The molecular structure of compound 7 is shown in
Figure 2, and selected geometric parameters are given in
the figure caption.
The palladium and tin atoms are four- and five-coordi-
nate, respectively, and exhibit a square-planar (Pd) and a
strongly distorted trigonal-bipyramidal (Sn) configuration
with the N(1), N(2) atoms occupying axial positions and the
O(1), C(1), Pd(1) atoms occupying equatorial positions. The
distortion from the ideal trigonal bipyramid is especially
manifested by the N(1)-Sn(1)-N(2) angle of 146.61(12)ꢀ,
which differs significantly from the ideal value of 180ꢀ. The
Pd(1)-N(3) distance of 2.154(4) A is comparable to those
found in related monomeric palladium complexes contain-
ing similar C,N-chelating ligands (range 2.140-2.155 A),18
but is longer than those found in the dimeric complex
(12) Abugideiri, F.; Fettinger, J. C.; Keogh, D. W.; Poli, R. Organo-
metallics 1996, 15, 4407.
(13) (a) Cole, A. A.; Mattamana, S. P.; Poli, R. Polyhedron 1996, 15,
2351. (b) Bush, M. A.; Hardy, A. D. U.; Manojlovic-Muir, L.; Sim, G. A.
J. Chem. Soc. A 1971, 1003–1009. (c) Chaiwaise, S.; Fenn, R. H. Acta
Crystallogr., Sect. B 1968, B24, 525.
(14) (a) Fenn, R. H.; Cross, J. H. J. Chem. Soc. A 1971, 3312. (b)
Churchill, M. R.; Fennessey, J. P. Inorg. Chem. 1968, 7, 953.
(15) (a) Hardy, A. D. U.; Sim, G. A. J. Chem. Soc., Dalton Trans.
1972, 1900. (b) Sim, G. A.; Sime, J. G.; Woodhouse, D. I.; Knox, G. R. Acta
Crystallogr., Sect. B 1979, B35, 2403.
(16) Eichler, B. E.; Phillips, A. D.; Haubrich, S. T.; Mork, B. V.;
Power, P. P. Organometallics 2002, 21, 5622.
(18) For most recent structures see for example: (a) Qin, Y.; Lang, H.;
Vittal, J. J.; Tan, G. K.; Selvaratnam, S.; White, A. J. P.; Williams, D. J.;
Lejny, P. H. Organometallics 2003, 22, 3944. (b) Dunina, V. V.; Gorunova,
O. N.; Grishin, Y. K.; Kuz'mina, L. G.; Churakov, A. V.; Kuchin, A. V.;
Howard, J. A. K. Russ. Chem. Bull. 2005, 2010. (c) Apfelbacher, A.;
Braunstein, P.; Brissieux, L.; Walter, R. Dalton Trans. 2003, 1669. (d)
McCarthy, M.; Goddard, R.; Guiry, P. J. Tetrahedron: Asymmetry 1999, 10,
2797. (e) Dunina, V. V.; Kuz'mina, L. G.; Rubina, M. Y.; Grishin, Y. K.; Veits,
Y. A.; Kazakova, E. I. Tetrahedron: Asymmetry 1999, 10, 1483.
(17) Weidenbruch, M.; Stilter, A.; Peters, K.; von Schnering, H. G. Z.
Anorg. Allg. Chem. 1996, 622, 534.

Article
Organometallics, Vol. 28, No. 16, 2009 4781
Figure 1. Molecular structure of 6 together with selected bond
lengths (A) and angles (deg). The data of only one of the two
independent molecules are given. Sn(1)-Mo(1) 2.7195(9), Sn-
(1)-Cl(2) 2.452(2), Sn(1)-N(1) 2.494(6), Sn(1)-N(2) 2.567(7);
Sn(1)-C(8) 2.120(10), Sn(1) Cl(1) 2.972(2), Mo(1)-Cl(1)
3 3 3
2.521(2); C(8)-Sn(1)-Mo(1) 145.8(2), C(8)-Sn(1)-N(1)
71.2(3), C(8)-Sn(1)-N(2) 74.2(3), N(1)-Sn(1)-N(2) 145.2(2),
N(1)-Sn(1)-Mo(1) 104.3(2), N(2)-Sn(1)-Mo(1) 106.4(2),
C(8)-Sn(1)-Cl(2) 98.0(2), N(1)-Sn(1)-Cl(2) 93.3(2), Mo(1)-
Sn(1)-Cl(2) 116.2(5), N(2)-Sn(1)-Cl(2) 87.6(2).
({2-(Me2NCH2)C6H4}Pd-μ-Cl)2 (2.073 A).19 The Sn(1)
atom is coordinated trans to the N(3) atom (Sn(1)-Pd(1)-
N(3) 174.60(13)ꢀ) at a Pd(1)-Sn(1) distance of 2.4972(6) A,
which is nearly identical to 2.4956(8) A found in the chloro-
substituted analogue 4. The Sn(1)-N(1) and Sn(1)-N(2)
distances are 2.441(3) and 2.533(3) A, respectively. The
Sn(1)-O(1) (2.097(3) A) and Sn(1)-O(2) (3.037(3) A)
distances are rather different and hint at a monodentate rather
than a bidentate coordination mode of the acetate substi-
Figure 2. Molecular structure of 7 together with selected bond
lengths (A) and angles (deg): Sn(1)-Pd(1) 2.4972(6), Sn(1)-
C(1) 2.123(4), Sn(1)-N(1) 2.441(3), Sn(1)-N(2) 2.533(3), Sn(1)-
O(1) 2.097(3), Pd(1)-C(21) 1.995(4), Pd(1)-Cl(1) 2.3972(12),
Pd(1)-N(3) 2.157(3); C(1)-Sn(1)-Pd(1) 132.93(11), C(1)-Sn-
(1)-O(1) 100.52(14), O(1)-Sn(1)-Pd(1) 125.22(9), N(1)-Sn-
(1)-N(2) 146.61(12), Sn(1)-Pd(1)-N(3) 174.60(13), Cl(1)-
Pd(1)-C(21) 176.24(12).
tuent. Notably, there are intramolecular Cl(1) H(29C) and
3 3 3
Cl(1) H(7A) distances of 2.785(1) and 2.838(1) A, which are
3 3 3
shorter than the sum of the van der Waals radii for chlorine
(1.70-1.90 A) and hydrogen (1.20-1.45 A).
In addition to the aromatic proton resonances and the
singlet for the acetate protons, the 1H NMR spectrum of 7
shows three equally intense singlet resonances for the
N-methyl (δ 1.97, 2.66, 2.95) protons, and a singlet (δ 4.00)
and an AB-type resonance (δ 3.78) for the N-methylene
protons. These resonances unambiguously indicate that
compound 7 is stereochemically rigid on the 1H NMR time
scale. The 119Sn NMR spectrum shows a singlet at δ -202
that is low-frequency shifted compared to the chloro-sub-
stituted complex 4.
meters. The chemical shifts δ are given in ppm and referenced
to external SiMe4 (1H, 13C), H3PO4 (85%, 31P), and SnMe4
(
119Sn). The IR spectra were recorded on a Perkin-Elmer 684
spectrometer. Electrospray mass spectra (ESI-MS) were re-
corded in the positive mode on an Esquire3000 ion trap analyzer
(Bruker Daltonics) and in the negative mode on the Platform
quadrupole analyzer.
Reaction of [2,6-(Me2NCH2)2C6H3]SnCl (1) with Pd(PPh3)4.
Tetrakis(triphenylphosphine)palladium(0) (0.13 g, 0.12 mmol)
was added to a magnetically stirred solution of the organostan-
nylene 1 (0.08 g, 0.23 mmol) in THF (5 mL). Stirring was
continued for 12 h, during which precipitation of a yellow solid
was observed that was isolated and identified as 3. The 31P NMR
spectrum of the remaining THF solution showed resonances at
δ 34.2 (integral 1, trans-Pd(PPh3)2Cl2) and -4.8 (integral 15,
PPh3).
In conclusion we have shown (i) that the intramolecularly
coordinated organostannylene 1 is a two-electron donor,
even to transition metal moieties containing TM-Cl bonds,
(ii) that the organostannylene 1 is an oxidizing reagent
toward Pd(PPh3)4, and (iii) that in the organostannylene
palladium complex 7 a nucleophilic attack is preferred at the
Sn-Cl over the Pd-Cl functionality.
Synthesis of [{2,6-(Me2NCH2)2C6H3}SnCl](C5H5)Mo(CO)2-
Cl] (6). A slurry of [CpMo(CO)2(NCCH3)2][BF4]11b (0.10 g;
0.26 mmol) in THF (25 mL) was treated with 1 (0.20 g,
0.58 mmol). After stirring the reaction mixture for 16 h the
solvent was evaporated in vacuo to give a solid residue that was
washed with n-hexane (3 ꢀ 10 mL) and then extracted with
CH2Cl2. The extract was evaporated and the crude product was
recrystallized from CH2Cl2/hexane to give 126 mg (82% yield)
of 6 as red crystalline material with mp 198 ꢀC (dec). Anal. Calcd
for C19H25Cl2MoN2O2Sn (598.96): C, 38.10; H, 4.21. Found: C,
38.07; H, 4.19. 1H NMR (CDCl3, 500.13 MHz): δ (ppm) 2.54 (s,
12H, NCH3), 3.79 (AB system, 4H, CH2N), 5.51 (s, 5H, C5H5),
Experimental Section
General Methods. The starting compounds 1 and 2 were
prepared according to literature.7c,9 All reactions were carried
out under argon, using standard Schlenk techniques. Solvents
were dried by standard methods, distilled prior to use,
and operations involving silver salts were light protected. The
1H, 13C, 31P, and 119Sn NMR spectra were recorded at ambient
temperature on Bruker Avance 500 and DPX 300 spectro-
(19) Mentek, A.; Kemmitt, R. D. W.; Fawcett, J.; Russell, D. R.
J. Mol. Struct. 2004, 693, 241.

ꢀ
Martincova et al.
4782 Organometallics, Vol. 28, No. 16, 2009
7.05 (d, 2H, ArH), 7.26 (t, 1H, ArH). 13C NMR (CDCl3,
125.7 MHz): δ (ppm) 46.6 (NCH3), 65.8 (CH2N), 92.6 (C5H5),
125.9, 130.0, 144.2, 149.8, 266.7 (2C, CO). 119Sn NMR (CDCl3,
186.5 MHz): δ (ppm) 105.4. IR (KBr): ν(cm-1) 1946(vs) [ν(CO)],
1860(vs) [ν(CO)].
The white residue that is insoluble in CH2Cl2 was analyzed by
1H NMR spectroscopy, elemental analysis, and ESI-MS, sug-
gesting the formation of organostannylenium salt {[2,6-(Me2-
NCH2)2C6H3]Sn(CH3CN)þ}BF4- Anal. Calcd for C14H22BF4-
N3Sn (437.84): C, 38.41; H, 5.06. Found: C, 38.08; H, 5.39. 1H
NMR (CD3CN, 500.13 MHz): δ (ppm) 2.75 (NCH3), 4.27
(NCH2), 7,56, 7.97 (C6H4). ESI-MS: negative mode m/z 87
[BF4]-; positive mode m/z 193 [C12H21N2]þ.
rhombic, space group P2c-2n, a=14.7541(5) A, b=9.0836(3) A,
c = 32.1522(11) A, R = 90ꢀ, β = 98.0965(9)ꢀ, γ = 90ꢀ, Z = 4,
F =1.843 g cm-3, μ=2.006 mm-1, crystal size 0.38 ꢀ 0.25ꢀ
3
0.15 mm, crystal shape block, θ range 2.33-29.24ꢀ, Tmin, Tmax
0.5161, 0.7529, 76 740 reflections collected, of which 12 669 were
independent [R(int) = 0.0763], [I > 2σ(I)]: R1=0.0549, wR2 =
0.1195.
For 7: C23H34ClN3O2PdSn, M=645.07, triclinic, space group
P1, a=9.5414(13) A, b=9.6605(16) A, c=14.696(2) A, R=
93.684(6)ꢀ, β=90.180(8)ꢀ, γ=108.526(8)ꢀ, Z=2, F(calcd) =
1.672 Mg/m-3, μ=1.804 mm-1, crystal size 0.08ꢀ0.08ꢀ0.06 mm,
crystal shape block, θ range 2.92-25.35ꢀ, 11 680 reflections
collected, of which 4685 were independent [R(int) = 0.04], no.
of observed reflections [I > 2σ(I)] 2347, no. of parameters 287, S
all data 0.519, final R indices [I > 2σ(I)]: R1 = 0.0276, wR2=
0.0526.
The empirical absorption corrections were applied (multiscan
from symmetry-related measurements). The structures were
solved by the direct method (SIR9720) and refined by a full-
matrix least-squares procedure based on F2 (SHELXL9721).
Hydrogen atoms were fixed in idealized positions (riding
model) and assigned temperature factors Hiso(H)=1.2Ueq(pivot
atom); for the methyl moiety a multiple of 1.5 was chosen. The
final difference maps displayed no peaks of chemical signifi-
cance.
Synthesis of {[2,6-(Me2NCH2)2C6H3](O2CCH3)Sn}[2-(Me2-
NCH2)C6H4]PdCl (7). Under magnetic stirring, AgOAc (52 mg,
0.31 mmol) was added to a solution of 1 (195 mg, 0.31 mmol) in
THF (40 mL). After stirring for 2 h, the suspension was filtered
and the solvent was evaporated to give a yellow solid residue,
which was washed with hexane (2ꢀ10 mL). The residue was
recrystallized from CH2Cl2/hexane to give 180 mg (90%) of 7 as
yellow crystalline material with mp 141 ꢀC (dec). Anal. Calcd for
C23H35ClN3O2PdSn (646.10): C, 42.46; H, 5.16. Found: C,
1
42.34; H, 5.03. H NMR (C6D6, 500.13 MHz): δ (ppm) 1.97
(s, 6H, NCH3), 2.49 (s, 3H, OAc), 2.66 (s, 6H, NCH3), 2.95 (s,
6H, NCH3) 3.78 (AB system, 4H, CH2N), 4.00 (s, 2H, CH2N)
6.79 (d, 2H, ArH), 7.00 (t, 1H, ArH) 7.27-7.55 (m, 4H, ArH).
13C NMR (C6D6, 125.77 MHz): δ (ppm) 21.1 (OAc), 46.8
(NCH3), 49.7 (NCH3), 64.5 (CH2N), 72.5 (CH2N), 122.7,
125.1, 125.3, 129.7, 142.2, 142.5, 143.7, 144.9, 148.7, 149.7.
119Sn NMR (C6D6, 186.49 MHz): δ (ppm) -202.
Crystallography. Single crystals of 6 (red) and 7 (yellow) were
obtained by slow evaporation from their respective solutions in
dichloromethane/n-hexane. Crystals were mounted on a glass
fiber with epoxy cement and measured on a KappaCCD dif-
fractometer with a CCD area detector by monochromatized Mo
KR radiation (λ = 0.71073 A) at 100(2) K. The details pertain-
ing to the data collection and refinement for crystals are as
follows. For 6: C18H24Cl2MoN2O2Sn, Mr = 1195.86, ortho-
Acknowledgment. The authors thank the Grant
Agency of the Czech Republic (project no. GA370468),
the Ministry of Education of the Czech Republic (project
nos. VZ0021627501 and LC523), and the Erasmus Pro-
€
gram of the EU and Technische Universitat Dortmund
for financial support.
Supporting Information Available: Further details of the
structure determination of compounds 6 and 7, including
atomic coordinates, anisotropic displacement parameters,
and geometric data are available free of charge via the
Internet at http://pubs.acs.org. Crystallographic data for
compounds 6 and 7 have been deposited with the Cambridge
Crystallographic Data Centre, CCDC no. 682434 and no.
713747).
(20) Sheldrick, G. M. SHELX-97 program package; University of
Goettingen, 1997.
(21) Sheldrick, G. M. SHELXTL V 5.10; Bruker AXS Inc.: Madison,
Wl, 1997.