Preparation, properties, and structures of pentanuclear [{Ni2l}2(μ-csalen)M]2+ complexes (l = macrocyclic N6S2 donor ligand)

Article abstract of DOI:10.1002/zaac.201400427

The dinuclear nickel complex [Ni₂L(μ-Cl)]⁺ (1), where L^2- is a 24-membered macrocyclic N₆S₂ ligand, reacts readily with 3-form-yl-4-hydroxy-benzoic acid (Hfhba) to form the carboxylato-bridged complex [Ni₂L(μ-fhba)]⁺ (2). Complex 2 undergoes a condensation reaction with ethylene diamine to produce a tetranuclear complex [{Ni₂L}₂(μ-H₂csalen)]²⁺ + (3), in which two dinuclear {Ni₂L} units are bridged via the deprotonated carboxylate functions of the csalen ligand N,N′-bis(4-carboxysalicylidene)-1,2-diaminoethane. The same compound can also be prepared directly from 1 and H2csalen. The complexation of 3 with NiCl₂?6H₂O, Cu(OAc)₂?H₂O or Pd(OAc)₂ provides pentanuclear complexes of the type [{Ni₂L}₂(μ-csalen)M]²⁺ [M = Ni (4a), Cu (4b), Pd (4c)]. All complexes were isolated as perchlorate salts and studied by ESI-MS, infrared, and UV/Vis spectroscopy. The tetraphenylborate salt of 4c was also characterized by X-ray crystallography. The [(csalen)M] complex units act in all cases as quadridentate bridging ligands linking two bioctahedral {Ni₂L} units via μ-1,3-bridging carboxylate functions. The palladium complex 4c was found to catalyze Heck-coupling reactions of various iodobenzenes with methyl acrylate and styrene.

Full text of DOI:10.1002/zaac.201400427

Journal of Inorganic and General Chemistry
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ARTICLE
Zeitschrift für anorganische und allgemeine Chemie
DOI: 10.1002/zaac.201400427
2+
Preparation, Properties, and Structures of Pentanuclear [{Ni L} (μ-csalen)M]
2
2
Complexes (L = Macrocyclic N S Donor Ligand)
6
2
[a]
[a]
Matthias Golecki and Berthold Kersting*
Keywords: Polynuclear complexes; Macrocyclic ligands; Salen ligands; Palladium; Heck reaction
+
2–
2 2
L}
(μ-csalen)M]2+ [M = Ni
Abstract. The dinuclear nickel complex [Ni
is a 24-membered macrocyclic N ligand, reacts readily with 3-form-
yl-4-hydroxy-benzoic acid (Hfhba) to form the carboxylato-bridged salts and studied by ESI-MS, infrared, and UV/Vis spectroscopy. The
complex [Ni tetraphenylborate salt of 4c was also characterized by X-ray crystal-
L(μ-fhba)]+ (2). Complex 2 undergoes a condensation
reaction with ethylene diamine to produce a tetranuclear complex lography. The [(csalen)M] complex units act in all cases as quadrident-
2
L(μ-Cl)] (1), where L
pentanuclear complexes of the type [{Ni
(4a), Cu (4b), Pd (4c)]. All complexes were isolated as perchlorate
6 2
S
2
2
+
[
{Ni
2
L}
2
(μ-H
2
csalen)] (3), in which two dinuclear {Ni
2
L} units are ate bridging ligands linking two bioctahedral {Ni
2
L} units via μ-1,3
-
bridged via the deprotonated carboxylate functions of the csalen ligand
bridging carboxylate functions. The palladium complex 4c was found
N,NЈ-bis(4-carboxysalicylidene)-1,2-diaminoethane. The same com-
to catalyze Heck-coupling reactions of various iodobenzenes with
methyl acrylate and styrene.
pound can also be prepared directly from 1 and H
2
csalen. The com-
plexation of 3 with NiCl
2
·6H
2
O, Cu(OAc)
2
·H
2
O or Pd(OAc) provides
2
Introduction
In the past ten years we have reported the synthesis of a
number of tetranuclear, mixed ligand complexes of the type
2
2 2 2 2 2
+
[
{M L} {μ-O C–R–O C}] , in which {M L} represents a
bowl-shaped complex unit supported by a macrocyclic N S
6
2
2–
donor ligand that embraces a bridging O C–R–O C dicarb-
2
2
oxylate dianion (Figure 1). Typical examples are Ni4 com-
plexes with acetylenedicarboxylato, terephthalato, isophthal-
[
1]
[2]
ato and 1,1Ј-ferrocene dicarboxylato ligands. They are
readily prepared by substitution reactions between the
+
chlorido-bridged complex [Ni L(μ-Cl)] and the correspond-
2
ing dicarboxylato dianion.[ Compounds of this sort are of
3]
interest in the targeted construction of exchange-coupled high-
spin molecules and due to confinement effects that are associ- macrocyclic ligand H L and representation of the structure of tetranu-
L(μ-LЈ)]+ of the
Figure 1. Structure of dinuclear complexes [M
2
2
2
+
clear [{M
2 2 2 2
L} {μ-O C–R–O C}] complexes with dicarboxylato li-
ated with the encapsulation of the guest molecule by the
2
+
gands (the macrocycle L is represented as an ellipse for clarity).
[
Ni L] units. The complexation of naphthalene diimide di-
2
carboxylato ligands, for example, leads to a substantial
[
4]
(
Ͼ 95%) quenching of the diimide fluorescence, while en-
II
I
II
–
–
–
M = Pd , Rh , Pt ; LЈ = Cl , Br , I ], is encapsulated by the
capsulation of the Fe(CpCO H) unit leads to a significant shift
2
2
[5]
two {Ni L} hemispheres. These compounds could be pre-
of its oxidation potential.[
2]
2
pared in much the same way as those bearing the purely or-
ganic dicarboxylato ligands, i.e. by reacting [Ni L(μ-Cl)] with
the corresponding [MCl (dppba) ] dicarboxylate dianion. It
was also possible to use the alternate sequence, in which the
metallophosphine ligand [Ni L(μ-dppba)] is coupled with a
suitable 4d or 5d complex. It was further demonstrated that the
chlorido ligands bonded to the 4d or 5d element can be substi-
tuted by Br or I without affecting the pentanuclear nature of
the complexes. The facile formation of such compounds, their
robust nature coupled with a potential for catalytic transforma-
tions at the central 4d or 5d element led us to synthesize deriv-
atives bearing a carboxylated salen complex as a bridging li-
2+
We have also described related [{Ni L} (μ-dppba) MLЈ ]
complexes, where a metallodicarboxylato ligand, namely
MLЈ (dppba) ] [dppba = 4-(diphenylphosphanyl)benzoate;
2
2
2
2
+
2
2–
2
–
2
2
[
2 2
+
2
*
Prof. Dr. B. Kersting
Fax: +49-341-97-36199
E-Mail: b.kersting@uni-leipzig.de
[a] Institut für Anorganische Chemie
–
–
Universität Leipzig
Johannisallee 29
04103 Leipzig, Germany
Supporting information for this article is available on the WWW
under http://dx.doi.org/10.1002/zaac.201400427 or from the au-
thor.
Z. Anorg. Allg. Chem. 2015, 641, (2), 436–441
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gand (Figure 2). Our first attempts afforded three such com-
2
+
II
II
plexes, namely [{Ni L} (μ-csalen)M] [M = Ni (4a), Cu
(
2
2
II
4b), Pd (4c)]. Their preparation and structural characteriza-
tion by NMR, IR, UV/Vis spectroscopy, and X-ray crystal-
lography is reported herein. Results concerning the catalytic
activity of 4c in Heck coupling reactions of iodobenzenes with
methyl acrylate and styrene are also reported.
Scheme 1. Synthesis of complexes 2–4c. The macrocycle is repre-
sented as ellipse for clarity.
Figure 2. Structure of pentanuclear complexes of the type [{Ni
2
L}
C}]2 (the macrocycle L is shown as an ellipse for clarity).
2 2
O C–R–O
2
{μ-
+
2+
csalen)Ni] , which was isolated as a perchlorate salt (4a) in
4% yield. Using Cu(OAc) ·H O or Pd(OAc) instead of
9
2
2
2
Results and Discussion
NiCl ·6H O provided the corresponding Ni Cu (4b) and Ni Pd
2
2
4
4
salts (4c) in similar good yields.
All compounds are air stable in solution as well as in the
Synthesis and Characterization of Compounds
The synthesis of the complexes is shown in Scheme 1. The solid state. The perchlorate salts exhibit good solubility in po-
reaction of [Ni L(μ-Cl)](ClO ) (1) with 3-formyl-4-hydroxy- lar aprotic solvents such as MeCN and CH Cl . They are less
2
4
2
2
+
benzoate afforded the dinuclear complex [Ni L(μ-fhba)] , soluble in alcohol and virtually insoluble in water. The com-
2
which was isolated as its perchlorate salt 2 in 89% yield. The plexes were characterized by ESI-MS, IR, UV/Vis spec-
corresponding zinc complex 2* was prepared as well, but only troscopy, and in case of 2* also by NMR spectroscopy to as-
for comparative purposes. A subsequent [2+1] imine conden- certain the formulation of the products. Table 1 lists selected
sation of 2 with ethylenediamine gave the tetranuclear complex analytical data.
2
+
[
3
{Ni L} (μ-H csalen)] as an air-stable green perchlorate salt
The ESI mass spectra of 2–4c reveal base peaks with the
2
2
2
+
in almost quantitative yield, attributable to its low solubility, correct isotopic distribution for the [Ni L(μ-fhba)] ,
which drives the reaction to completion. The same compound [{Ni L} (μ-H csalen)] , and [{Ni L} (μ-csalen)M] cations
2
2+
2+
2
2
2
2
2
is also accessible in one step from 1 and N,NЈ-bis(4-carboxysa- in each case (see Supporting Information). The IR spectra
licylidene)-1,2-diaminoethane. Treatment of 3 with a slight ex- show bands arising from the [Ni L] fragment, the ClO4–
2+
2
cess of NiCl ·6H O for
5 h resulted in the clean counterions, and the bridging salicylidene or salen units. The
2
2
[
6,7]
formation of the orange-colored complex [{Ni L} (μ- carboxylate groups gives rise to two strong vibrations,
as
2
2
Table 1. Selected characterization data for complexes 2–4c.
Compound
ESI-MS, m/z
ν
as(RCO –
2
) /cm–1
ν(CH=O,N) /cm–1
UV/Vis,a)
λmax /nm
2
949.4
965.3
962.9
991.3
993.4
1015.3
1594
1593
1589
1575
1575
1576
1657
1654
1632
1613
1610
1610
232, 304, 330, 388, 648, 1118
231, 257, 285, 332
236, 331, 378, 648, 1124
261, 295, 335, 406, 661, 1127
258, 332, 398, 667, 1131
227, 265, 333, 648, 1121
2
3
4
4
4
*
a
b
c
2 2
a) UV/Vis spectra were recorded in CH Cl at ambient temperature.
Z. Anorg. Allg. Chem. 2015, 436–441
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2
– [8,9]
in other μ1,3-carboxylato-bridged Ni complexes of (L) ,
2
–
1
–
–1
around 1600–1575 cm [νasym(RCO )] and 1420–1400 cm
νsym(RCO )], indicating that the salicylidene and salen li-
2
–
[
2
gands are also bound in this fashion. The IR absorptions of
the coordinated carboxylates are slightly red-shifted relative to
those of the free acids. The large separation of the two carb-
–1
oxylate stretching modes (Δν = νasym – νsym Ͼ 160 cm ) is
also in line with a bridging mode. The bands for the aldehyde
or imine groups are observed at 1657 (2), 1632 (3), and around
–
1
1
610 cm (4a–4c). Each compound shows two weak absorp-
3
3
tion bands in the UV/Vis attributable to the ν ( A Ǟ T )
648–667 nm) and ν1 ( A
2
2g
1g
2 2
Figure 4. Structure of the [{Ni L}
(μ-csalen)Pd]2+ cation in crystals
3
3T2g) transitions (1118–
(
Ǟ
2g
of 4cЈ. Thermal ellipsoids are drawn at the 50% probability level.
Hydrogen atoms omitted for clarity. Selected bond lengths /Å: Pd1–
1
131 nm) of an octahedral NiN S O chromophore. The salen
3
2
complexes 4a–4c exhibit strong absorptions below 400 nm, O3 1.994(4), Pd1–N7 1.942(5), Ni1–O1 1.970(4), Ni1–N1 2.209(6),
which are attributed to thiolateǞNi2 charge transfer and π– Ni1–N2 2.166(6), Ni1–N3 2.288(5), Ni1–S1 2.441(2), Ni1–S2
+
2.494(2), Ni2–O2 2.005(4), Ni2–N4 2.345(5), Ni2–N5 2.157(5), Ni2–
π* transitions within the ligands. The latter absorptions ob-
scure the d–d transitions for the planar [M(salen)]
as the ν ( A Ǟ T (F)) transition of the NiN S O unit.
N6 2.196(5), Ni2–S1 2.437(2), Ni2–S2 2.486(2). Symmetry code used
to generate equivalent atoms: 1–x, y, 1.5–z.
[10]
as well
3
3
3
2g
1g
3 2
1
+
The H NMR spectrum of the diamagnetic [Zn L(μ-fhba)]
2
As can be seen, two [Ni L]+ units are united by the
complex (Supporting Information) shows two singlet signals
2
+
5
6
13
[Pd(csalen)] complex. The [Ni L(O CR)] subunits are iso-
(4ϫC H , 2ϫC H ) for the six N–Me groups. The C NMR
2
2
3
3
structural with other carboxylate complexes supported by the
spectrum reveals only 11 signals (seven aliphatic and four aro-
matic) for the 38 carbon atoms of the [Zn L] fragment. The
[1,2]
2
+
N S macrocycle.
6 2
The carboxylate groups are coordinated
2
in a bidentate bridging mode. The supporting ligand adopts the
bowl-shaped “cone” conformation. The average Ni–N, Ni–S,
and Ni–O bond lengths at 2.227(6), 2.465(2), and 1.988(4) Å,
respectively, are normal as is the Ni···Ni distance of 3.496(1) Å
tert-butyl groups in 2* at δ = 0.97 ppm are high-field shifted
relative to those of free H L (δ =1.30 ppm), showing that they
2
are located in the shielding region of the fhba co-ligand. All
data are in agreement with a bowl-shaped, C symmetric
2
v
+
[3.499(1) Å]. The distance d between the center of the Ni···Ni
structure of the [Zn L(μ-fhba)] cation as shown in Figure 3.
2
+
axes of the two [Ni L] subunits is 18.832 Å. A similar dis-
2
tance was observed in the naphthalene diimide complex
{Ni L} (μ-NDI](BPh ) (d = 19.010 Å).[ However, the
4]
[
2
2
4 2
packing in the latter compound is different from that in 4cЈ. In
the presented complex two Ph rings of the BPh4– anions are
engaged in offset face-to-face stacking interactions with the
planar [Pd(csalen)] moiety [d(ArH···centroid benzene ring =
3.213 Å) filling the voids within the tetranuclear complex as
illustrated in Figure 5. The structure is further stabilized by
intramolecular CH···π interactions between the tBu methyl
groups and the aromatic rings of the salen moietys
Figure 3. Schematic representation of the bowl-shaped macrocycle
conformation in 2 and 2*.
Description of the Crystal Structure of Complex 4c
Efforts to obtain single crystals of 4a–4c suitable for X-
ray diffraction analysis proved unsuccessful. However, such
crystals were obtained in the case of the tetraphenylborate salt
[
{Ni L} (μ-csalen)Pd](BPh ) (EtOH) (4cЈ) grown by slow
2 2 4 2 2
evaporation from a 1:1 dichloromethane/ethanol solvent sys-
tem. Crystals of 4c are monoclinic space group C2/c. The crys-
2
+
tal structure consists of [{Ni L} (μ-csalen)Pd] dications, tet-
2
2
Figure 5. Van der Waals representation of the molecular structure of
raphenylborate ions, and heavily disordered ethanol solvate
[
{Ni
face stacking interactions between the Ph rings of the BPh
the [(csalen)Pd] linker entity are obvious from this view (carbon atoms
2 2 4 2
L} (μ-csalen)Pd](BPh ) in crystals of 4cЈ. The offset face-to-
molecules. Figure 4 shows the molecular structure of the Ni Pd
–
4
4
ions and
complex, which exhibits crystallographically imposed C sym-
2
–
metry. Selected bond lengths are given in the figure caption.
of the BPh
4
ions highlighted in light gray).
Z. Anorg. Allg. Chem. 2015, 436–441
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Table 2. Heck reaction of aryl halides with olefins using Pd complex 4c.a)
Entry
1
Aryl halide
Olefin
Product
Timeb) /min
3 h
Conversionc) /%
100%
2
3
4 h
4 h
100%
100%
4
5
0%
0%
a) General conditions: aryl halide (1 mmol), olefin (3 mmol), triethylamine (3 mmol), DMF (5 mL), 0.5 mol% Pd catalyst, 130 °C. b) The
reaction progress was monitored by thin layer chromatography. c) Isolated yield.
2+
d(CtBuMe···centroid benzene ring) = 3.883 Å (C36···X1a)]. In plexation of the tetranuclear [(Ni L) (μ-csalen] complex (3)
[
[
2 2
{Ni L} (μ-NDI](BPh ) , adjacent complexes interact only by and the desired metal(II) salt. The starting complex 3 was
2
2
4 2
intermolecular CH···π interactions leading to a two-dimen- either accessible by a ligand template synthesis starting with
–
sional interdigitated packing of the molecules, with the BPh
the 3-formyl-4-hydroxy-benzoato bridged complex [Ni L(μ-
4
2
2+
+
ions being well separated from the [{Ni L} (μ-NDI)] dicat- fhba)] and ethylene diamine, or by a substitution reaction of
ion. The average Pd–N and Pd–O distances in 4cЈ at 1.942(5) [Ni L(μ-Cl)] with N,NЈ-bis(4-carboxysalicylidene)-1,2-diami-
2
2
+
2
and 1.994(4) Å compare well with other four-coordinate palla- noethane. The latter method is superior since it involves only
[
11,12]
dium N O complexes.
one step. The new complexes could be isolated as perchlorate
salts and were characterized by elemental analyses, ESI mass
spectrometry, IR and UV/Vis spectroscopy, and where appro-
2
2
Activity of 4c in the Heck Coupling of Iodobenzenes with
Methyl Acrylate and Styrene
1
13
priate by H and C NMR spectroscopy. In addition the mo-
2+
lecular structure of [(Ni L) (μ-(csalen)Pd] (4c) was charac-
2
2
The catalytic behavior of complex 4c in the Heck cou-
pling[13] of selected aryl halides with methyl acrylate and styr-
terized by single-crystal X-ray crystallography. The pentanu-
clear complex 4c was found to catalyze Heck coupling reac-
tions of various iodobenzenes with methyl acrylate and styr-
ene, although it is less active than the parent [Pd(salen)] com-
plex.
ene was tested in view of literature reports that palladium
Schiff base complexes exhibit high activities.
are summarized in Table 2. As can be seen 1-iodo-3,5-di-
methyl-benzene and 1,4-diiodobenzene reacted readily with
methylacrylate and styrene (entries 1–3), the dihalide being
somewhat less reactive. The reactions complete within 3–4 h
[14–16]
The results
Experimental Section
under aerobic conditions, with excellent selectivity for the β- General Methods and Instrumentation: Solvents and reagents were
arylated trans product in the presence of 0.5 mol% 4c. Without of reagent grade quality and used as received unless otherwise speci-
[
17]
a catalyst no conversions are observed, as was the case with fied. The compounds H
the halides 1,4-dibromo- or 1,4-dichlorobenzene. However, the
2
L·6HCl, [Ni
bis(4-carboxysalicylidene)-1,2-diaminoethane
2
L(μ-Cl)]ClO
4
(1),
and N,NЈ-
[
18]
were prepared ac-
cording to the literature. Melting points were determined with an Elec-
trothermal IA9100 instrument in open glass capillaries and are uncor-
rected. IR spectra were recorded with a Bruker Vector27 FT-IR spec-
trophotometer as KBr pellets. Electronic absorption spectra were re-
corded with a Jasco V-670 UV/Vis/near IR spectrophotometer, elemen-
tal analyses with a Vario EL-elemental analyzer. All syntheses were
carried out in a dinitrogen atmosphere using standard Schlenk-tech-
niques.
activity of 4c is much lower than that of the parent [Pd(salen)]
complex, which reacts about ten times faster than 4c.[14] Given
the steric hindrance exerted by the two demanding [Ni L] sub-
2
units this is not surprising.
Conclusions
Several pentanuclear complexes of composition [{Ni L} (μ-
csalen)M] [M = Ni (4a), Cu (4b) and Pd (4c)] were suc- therefore be prepared only in small quantities and handled with appro-
2
2
CAUTION! Perchlorate salts are potentially explosive and should
2
+
II
II
II
cessfully synthesized. The synthetic route involved the com- priate care.
Z. Anorg. Allg. Chem. 2015, 436–441
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[
Ni
2 4 2 2 2 4 2
L(μ-fhba)]ClO (2): A solution of 3-formyl-4-hydroxy-benzoic [{Ni L} (μ-H csalen](ClO ) (3): Method A: A solution of ethyl-
–
3
acid (117 mg, 0.70 mmol, 1.3 equiv.) and triethylamine (98 μL,
enediamine (37 μL, 0.55 mmol, ρ = 0.90 g·cm , 1 equiv.) in methanol
(5 mL) was added dropwise to a solution of 2 (1.15 g, 1.11 mmol,
2 equiv.) in acetonitrile (75 mL) The resulting green solution was
stirred for 12 h at room temperature. To the resulting suspension lith-
ium perchlorate trihydrate (878 mg, 5.47 mmol, 10 equiv.) in ethanol
–3
0
.71 mmol, ρ = 0.73 g·cm , 1.3 equiv.) was added dropwise to a yel-
low solution of 1 (500 mg, 0.55 mmol, 1.0 equiv.) in methanol
15 mL). The resulting green solution was stirred at room temperature
for 48 h. To the resulting suspension lithium perchlorate trihydrate
(
(435 mg, 2.71 mmol, 5.0 equiv.) in ethanol (25 mL) was added and (25 mL) was added to ensure complete precipitation of the title com-
stirred for 30 min. The solvent was evaporated under reduced pressure pound. After stirring for 30 min the solvent was evaporated under re-
to one third of the original volume. The resulting green solid was duced pressure to one third of the original volume and the resulting
filtered, washed with cold ethanol (5 mL), and ethyl ether (5 mL), and green solid was filtered, washed with cold ethanol (5 mL), and ethyl
dried in air. Evaporation of a solution of the crude product from a ether (5 mL), and dried in air. Evaporation of a solution of the crude
mixed 1:1 dichloromethane:ethanol solution (15 mL) provided the pure product from a mixed 1:1 dichloromethane:ethanol solution (15 mL)
compound as a microcrystalline powder. Yield: 506 mg (89%). M.p.
29–330 °C. C46 69ClN Ni (1051.05): calcd. C 52.57, H 6.62, 1.14 g (98%). Method B: A solution of N,NЈ-bis(4-carboxysalicylid-
N 8.00%; found C 52.37, H 6.58, N 7.89%. IR (KBr): ν˜ = 3442 (w), ene-1,2-diaminoethane (193 mg, 0.54 mmol, 1 equiv.) and triethyl-
provided the pure compound as a microcrystalline powder. Yield:
3
H
6
2 8 2
O S
–
3
2
961 (m), 2889 (m), 2867 (m), 1658 (m), 1624 (m), 1594 (m), 1462
amine (150 μL, 1.09 mmol, ρ = 0.73 g·cm , 2 equiv.) in methanol
(15 mL) was added dropwise to a solution of 1 (1.00 g, 1.09 mmol,
2 equiv.) in dichloromethane/methanol (100 mL, 1:1, v:v). The green
(s), 1398 (s), 1363 (m), 1316 (m), 1275 (m), 1233 (m), 1199 (w), 1153
(m), 1097 (vs), 1081 (vs), 1039 (m), 930 (w), 913 (w), 881 (w), 826
(
5
m), 817 (m), 807 (w), 778 (m), 752 (w), 718 (w), 623 (m), 564 (vw), solution was stirred for 3 d at room temperature. To the resulting sus-
–1
–1
–1
31 (vw) cm . UV/Vis (dichloromethane): λmax /nm (ε /m cm ) =
pension lithium perchlorate trihydrate (871 mg, 5.43 mmol, 10 equiv.)
2
32 (60153), 304 (18046), 330 (15519), 388 (1987), 648 (46), 1118 in ethanol (25 mL) was added and stirred for 30 min. The solvent was
+
(74). MS (ESI+, CH
3
CN): m/z = 949.4 ([Ni
2
L(μ-fhba)] ).
removed under reduced pressure to one third of the original volume
and the resulting green solid was filtered, washed with cold ethanol
(
5 mL) and ethyl ether (5 mL), and dried in air. Evaporation of a solu-
tion of the crude product from a mixed CH Cl :MeOH solution
15 mL, 1:1, v:v) provided the pure compound as micro-
crystalline powder. Yield: 1.13 g (97%). M.p. 336–337 °C.
·2H O (2162.19): calcd. C 52.22, H 6.81, N
[
(
(
(
2 4 2
Zn L(μ-fhba)]ClO (2*): To a colorless suspension of H L·6HCl
2
2
2.00 g, 2.25 mmol, 1.0 equiv.) and zinc perchlorate hexahydrate
1.92 g, 5.16 mmol, 2.3 equiv.) in methanol (100 mL) triethylamine
(
a
–3
2.59 mL, 18.7 mmol, ρ = 0.73 g·cm , 8.3 equiv.) was added drop-
C
9
2
(
(
9
94
H142Cl
2
N14Ni
4
O
14
S
4
2
wise. The resulting colorless solution was stirred for 72 h at room
temperature. A solution of 3-formyl-4-hydroxy benzoic acid (485 mg,
2
.07%; found C 52.20, H 6.57, N 9.06%. IR (KBr): ν˜ = 3444 (w),
960 (m), 2891 (m), 2867 (m), 1632 (s), 1589 (m), 1488 (m), 1461
s), 1421 (m), 1394 (s), 1363 (m), 1309 (w), 1278 (m), 1234 (m), 1201
vw), 1170 (vw), 1153 (w), 1096 (vs), 1077 (vs), 1040 (m), 1000 (vw),
.92 mmol, 1.3 equiv.) in methanol (20 mL) and triethylamine
–3
(405 μL, 2.92 mmol, ρ = 0.73 g·cm , 1.3 equiv.) were added dropwise.
The yellowish solution was stirred at room temperature for 48 h. To the
resulting suspension lithium perchlorate trihydrate (1.80 g, 11.2 mmol,
5
82 (vw), 930 (w), 912 (w), 881 (w), 825 (m), 817 (w), 779 (m), 752
–1
(
w), 693 (vw), 623 (m), 564 (vw), 535 (vw) cm . UV/Vis (dichloro-
.0 equiv.) in ethanol (25 mL) was added and stirred for 30 min. The
–1
–1
methane): λmax /nm (ε /m cm ) = 236 (91892), 331 (23935), 378
solvent was evaporated under reduced pressure to one third of the
original volume. The resulting colorless solid was filtered and washed
with cold ethanol (5 mL) and ethyl ether (5 mL), respectively. Evapo-
ration of a solution of the crude product from a mixed 1:1 dichlorome-
thane:ethanol solution (15 mL) provided the pure compound as a
microcrystalline powder. Yield: 2.04 g (85%). M.p. 325–326 °C.
(
(
3
5561), 648 (95), 1124 (147). MS (ESI+, CH CN): m/z = 962.9
2+
[{Ni
2
L}
2
(μ-H
2
csalen)] ).
[
0
{Ni
.12 mmol, 1 equiv.) in CH
solution of NiCl ·6H O (33.5 mg, 0.14 mmol, 1.2 equiv.) in MeOH
15 mL), and the mixture was refluxed for further 5 h. A solution of
LiClO ·3H O (189 mg, 1.18 mmol, 10 equiv.) in ethanol (25 mL) was
2
L}
2
(μ-csalen)Ni](ClO
4
)
2
(4a): To a green solution of 3 (250 mg,
2 2
Cl /MeOH (30 mL, 1:2, v/v) was added a
2
2
C
7
46
H
69ClN
.64%; found C 50.42, H 6.68, N 7.60%. H NMR (400 MHz,
2
D ]dichloromethane): δ = 9.70 (s, 1 H, H19), 8.12 (s, 1 H, H20), 7.53
6 8 2 2 2
O S Zn 2H O (1100.45): calcd. C 50.21, H 6.69, N
(
1
4
2
[
[
added and stirred for further 30 min. The solvent was removed under
reduced pressure to one third of the original volume and the resulting
green solid was filtered, washed with cold ethanol (5 mL), and ethyl
ether (5 mL). Evaporation of a solution of the crude product from a
4
3
4
d, 1 H, J(H,H) = 2.1 Hz, H14], 7.48 (dd, 1 H, JH,H = 8.7, JH,H
=
3
2
4
=
.1 Hz, H18), 6.92 (s, 4 H, H3), 6.70 (d, 1 H, JH,H = 8.7 Hz, H17),
.49 (d, 4 H, JH,H = 11.6 Hz, H7), 3.61 (td, 4 H, JH,H = 14.0, JH,H
2
2
3
2
3
3.8 Hz, H9), 3.33 (td, 4 H, JH,H = 14.0, JH,H = 3.7 Hz, H8), 3.00
2 2
mixed CH Cl :MeOH solution (15 mL, 1:1, v:v) provided the pure
2
3
(
s, 6 H, H6), 2.90 (dd, 4 H, JH,H = 14.1, JH,H = 3.6 Hz, H9), 2.68 compound as a microcrystalline powder. Yield: 241 mg (94%). M.p.
2
2
(d, 4 H, JH,H = 11.6 Hz, H7), 2.61 (s, 12 H, H5), 2.55 (dd, 4 H, JH,H
94 140 2 14 5 14 4 2
333–335 °C. C H Cl N Ni O S ·3H O (2236.88): calcd. C 50.47,
3
13
1
=
14.2, JH,H = 3.9 Hz, H8), 0.97 (s, 18 H, H11) ppm. C{ H} NMR H 6.58, N 8.77%; found C 50.39, H 6.46, N 8.64%. IR (KBr): ν˜ =
]dimethylsulfoxide): δ = 190.2 (C19), 166.3 (C12),
3442 (w), 2954 (m), 2891 (m), 2865 (m), 1613 (s), 1575 (s), 1462 (s),
62.5 (C16), 143.6 (C4), 142.1 (C2), 135.8 (C18), 133.4 (C1), 127.1 1422 (m), 1393 (vs), 1363 (m), 1349 (w), 1329 (w), 1311 (m), 1265
(100 MHz, [D
6
1
(
(
2
(
(
C14), 121.4 (C17), 63.0 (C7), 58.1 (C8), 56.9 (C9), 45.9 (C6), 45.7
C5), 33.8 (C10), 30.7 (C11) ppm. IR (KBr): ν˜ = 3448 (w), 2962 (m),
882 (m), 2862 (m), 1564 (m), 1625 (m), 1611 (m), 1593 (m), 1574
m), 1481 (m), 1462 (s), 1397 (s), 1365 (m), 1317 (m), 1292 (m), 1274
m), 1232 (m), 1202 (w), 1171 (w), 1154 (w), 1090 (vs), 1080 (vs),
(w), 1234 (w), 1200 (w), 1153 (w), 1097 (vs), 1077 (vs), 1059 (s),
1040 (m), 1001 (vw), 930 (w), 912 (w), 881 (w), 825 (m), 818 (m),
806 (w), 782 (w), 752 (vw), 701 (w), 662 (w), 624 (m), 564 (vw),
–
1
535 (vw), 469 (vw) cm . UV/Vis (dichloromethane):
–
1
–1
λmax /nm (ε /m cm ) = 261 (116791), 295 (74067), 335 (32888),
1
8
5
λ
055 (m), 1043 (s), 1007 (vw), 983 (w), 929 (w), 913 (w), 883 (w),
406 (7997), 661 (122), 1127 (158). MS (ESI+, CH CN): m/z = 991.3
3
2
+
23 (m), 806 (w), 780 (m), 751 (w), 716 (w), 624 (m), 597 (vw), ([{Ni L} (μ-csalen)Ni] ).
2
2
–1
61 (vw), 489 (vw) cm . UV/Vis (dichloromethane):
max/nm (ε/m–1 cm ) = 231 (41656), 257 (20340), 285 (19965), 332
–1
2 2 4 2
[{Ni L} (μ-csalen)Cu](ClO ) (4b): This compound was prepared in
analogy to 4a by using Cu(OAc) (H O) (28.2 mg, 0,14 mmol,
2 2
+
(284789). MS (ESI+, CH
3
CN): m/z = 965.3 ([Zn
2
L(μ-fhba)] ).
Z. Anorg. Allg. Chem. 2015, 436–441
440
© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Journal of Inorganic and General Chemistry
www.zaac.wiley-vch.de
ARTICLE
Zeitschrift für anorganische und allgemeine Chemie
1
.2 equiv.) instead of NiCl
2
·6H
2
O. Dark green solid. Yield: 235 mg Supporting Information (see footnote on the first page of this article):
1
13
(91%). M.p. 335–337 °C. C94
H140Cl
2
CuN14Ni
4
O
14
S
4
·5H
2
O (2277.67):
ESI-MS, IR, and UV/Vis spectra for 2–4c. H and C NMR spectra
1
calcd. C 49.57, H 6.64, N 8.61%; found C 49.50, H 6.31, N 8.63%. for 2*. H NMR spectra for Heck coupling products.
IR (KBr): ν˜ = 3446 (w), 2955 (m), 2885 (m), 2866 (m), 1628 (s),
1
(
1
610 (s), 1575 (m), 1528 (vw), 1462 (s), 1393 (vs), 1308 (m), 1266
w), 1235 (m), 1200 (w), 1170 (w), 1097 (vs), 1078 (vs), 1059 (m),
041 (m), 1001 (w), 930 (w), 912 (w), 882 (w), 825 (m), 782 (w), 753
Acknowledgements
This work was supported by the University of Leipzig and the ESF
–1
(
w), 694 (w), 653 (vw), 624 (m), 564 (vw) cm . UV/Vis (dichloro-
(
Europäischer Sozialfonds). M. Golecki thanks the Sächsische Aufbau-
methane): λmax /nm (ε /m–1 cm ) = 258 (78016), 332 (23755), 398
–1
bank (SAB) for an ESF grant.
3
(7755), 667 (311), 1131 (128). MS (ESI+, CH CN): m/z = 993.4
2+
([{Ni
2
L}
2
(μ-csalen)Cu] ).
[
{Ni L}
2
2
(μ-csalen)Pd](ClO
4
)
2
(4c): This compound was prepared in
(31.7 mg, 0,14 mmol, 1.2 equiv.)
O. Dark green solid. Yield: 252 mg (96%). M.p.
14PdS ·3H O (2284.61): calcd. C
9.42, H 6.44, N 8.58%; found C 49.20, H 6.31, N 8.45%. IR (KBr):
References
analogy to 4a by using Pd(OAc)
instead of NiCl ·6H
32–333 °C. C94
2
2
2
[
1] J. Klingele, M. H. Klingele, O. Baars, V. Lozan, A. Buchholz, G.
3
4
H140Cl
2
N14Ni
4
O
4
2
Leibeling, W. Plass, F. Meyer, B. Kersting, Eur. J. Inorg. Chem.
2007, 5277–5285.
ν˜ = 3443 (w), 2957 (m), 2879 (m), 2864 (m), 1610 (s), 1576 (s), 1462 [2] V. Lozan, A. Buchholz, W. Plass, B. Kersting, Chem. Eur. J. 2007,
s), 1393 (vs), 1389 (s), 1304 (m), 1265 (w), 1233 (w), 1201 (vw),
13, 7305–7316.
153 (w), 1096 (vs), 1077 (vs), 1040 (s), 930 (w), 912 (w), 881 (w), [3] U. Lehmann, J. Klingele, V. Lozan, G. Steinfeld, M. H. Klingele,
(
1
8
5
λ
25 (m), 780 (w), 752 (vw), 698 (w), 662 (w), 623 (m), 564 (vw),
S. Käss, A. Rodenstein, B. Kersting, Inorg. Chem. 2010, 49,
11018–11029.
[4] K. Lee, V. Lozan, S. Langford, B. Kersting, Dalton Trans. 2009,
–1
40 (vw), 473 (vw) cm . UV/Vis (dichloromethane):
max /nm (ε /m–1 cm ) = 227 (61889), 265 (89460), 333 (24555), 648
–1
7
481–7485.
5] M. Golecki, B. Kersting, Z. Anorg. Allg. Chem. 2013, 639, 2473–
481.
(131), 1121 (155). MS (ESI+, CH
3
CN): m/z = 1015.3 ([{Ni L} (μ-
2
2
[
[
[
[
2+
csalen)Pd] ).
2
6] K. Nakamoto, Infrared and Raman Spectra of Inorganic and Co-
ordination Compounds, 5th ed., Wiley, New York, 1997.
7] G. B. Deacon, R. J. Phillips, Coord. Chem. Rev. 1980, 33, 227–
Crystallography: The data set for 4cЈ was collected with a STOE
IPDS-2T diffractometer equipped with graphite monochromated Mo-
K radiation (0.71073 Å). The data were processed with X-Area.
α
The structure was solved by Direct Methods
[
19]
250.
[
20]
and refined by full-
2
8] B. Kersting, Angew. Chem. 2001, 113, 4110–4112; Angew. Chem.
Int. Ed. 2001, 40, 3987–3990.
[9] J. Hausmann, M. H. Klingele, V. Lozan, G. Steinfeld, D. Siebert,
Y. Journaux, J. J. Girerd, B. Kersting, Chem. Eur. J. 2004, 10,
1716–1728.
matrix least-squares on the basis of all data against F using SHELXL-
[21]
[22]
9
7.
was used for the artwork of the structures.
were refined with anisotropic thermal parameters. Hydrogen atoms
PLATON was used to search for higher symmetry.
Ortep3
[
23]
All non-hydrogen atoms
were placed at calculated positions and refined as riding atoms with [10] H. H. Jaffé, M. Orchin, Theory and Applications of Ultraviolet
Spectroscopy, J. Wiley, New York, 1962.
11] N. Kumari, R. Prajapati, L. Mishra, Polyhedron 2008, 27, 241–
isotropic displacement parameters.
[
[
[
[
2
48.
12] V. W. Day, M. D. Glick, J. L. Hoard, J. Am. Chem. Soc. 1968, 90,
803–4808.
Crystallographic data (excluding structure factors) for the structure in
this paper have been deposited with the Cambridge Crystallographic
Data Centre, CCDC, 12 Union Road, Cambridge CB21EZ, UK. Copies
of the data can be obtained free of charge on quoting the depository
number CCDC-1022580 (4cЈ) (Fax: +44-1223-336-033; E-Mail:
deposit@ccdc.cam.ac.uk, http://www.ccdc.cam.ac.uk)
4
13] L. S. Hegedus, Organische Synthese mit Übergangsmetallen,
VCH, Weinheim, 1995.
14] S. R. Borhade, S. B. Waghmode, Tetrahedron Lett. 2008, 49,
3423–3429.
[
[
15] P. Liu, X.-J. Feng, R. He, Tetrahedron 2010, 66, 631–636.
16] K. J. Miller, J. H. Baag, M. M. Abu-Omar, Inorg. Chem. 1999,
Crystal Data for 4cЈ(EtOH)
M = 2672.12 + 92.14 g·mol , monoclinic space group C2/c, a =
2
. C142
H
182
B
2
N
14Ni
4
O
6
PdS
4 2
(EtOH) ,
–1
38, 4510–4514.
3
4.5360(19), b = 20.9726(8), c = 21.0568(11) Å, β = 115.764(7), V =
[
17] a) B. Kersting, G. Steinfeld, Chem. Commun. 2001, 1376–1377;
b) M. H. Klingele, B. Kersting, Z. Naturforsch. 2001, 56b, 437–
439.
3
13735.5(12) Å , Z = 4 (the asymmetric units contains one half of the
–
3
–1
c
formula unit), D = 1.292 g·cm , μ = 0.786 mm , 45097 reflections
collected, 12071 unique. The EtOH solvate molecules are heavily dis-
ordered, and the electron density associated to these molecules was
[18] V. Peruzzo, S. Tamburini, P. A. Vigato, Inorg. Chim. Acta 2012,
387, 151–162.
[
19] XArea, IPDS and X-RED32, STOE & Cie, Darmstadt, Germany,
008.
removed from the structure (and the corresponding F
o
) with the
2
Squeeze procedure implemented in the Platon program suite. Final R
1
2
2
[20] G. M. Sheldrick, Acta Crystallogr., Sect. A 1990, 46, 467–473.
[21] G. M. Sheldrick, SHELXL-97, Computer Program for Crystal
Structure Refinement, University of Göttingen, Göttingen, Ger-
many, 1997.
[
F Ͼ 2σ(F )] = 0.0714, wR
2
(all data) = 0.1463, R
1
index based on
538 reflections with I Ͼ 2σ(I) (refinement on F2).
6
Typical Experimental Procedure for the Heck Reaction: In a typical
experiment the aryl halide (1 mmol), triethylamine (3 mmol), olefin
[
22] a) A. L. Spek, PLATON - A Multipurpose Crystallographic
Tool; Utrecht University, Utrecht, The Netherlands, 2000;
b) P. van der Sluis, A. L. Spek, Acta Crystallogr., Sect. A 1990,
(
3 mmol), and complex 4c (0.5 mol% based on halide) were dissolved
in DMF (5 mL). The resulting dark green solution was stirred at
30 °C for 3–4 h. The reaction progress was monitored by TLC. The
46, 194.
1
[
23] L. J. Farrugia, J. Appl. Crystallogr. 1997, 30, 565.
reaction mixture was cooled to room temperature, to precipitate the
coupling products, which were filtered and unambiguously charac-
Received: September 4, 2014
Published Online: October 28, 2014
1
terized by H-NMR spectroscopy (see Supporting Information).
Z. Anorg. Allg. Chem. 2015, 436–441
441
© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim