2-(1-Aryliminoethyl)cycloheptapyridylpalladium complexes: Synthesis, characterization and the use in the Heck-reaction

Article abstract of DOI:10.1016/j.ica.2013.08.008

A series of 2-(1-aryliminoethyl)cycloheptapyridine derivatives (L1-L7) were prepared in good yield by the condensation reaction of 2- acetylcycloheptapyridine with various anilines, and then reacted with PdCl ₂(CH₃CN)₂ in

Full text of DOI:10.1016/j.ica.2013.08.008

Inorganica Chimica Acta 407 (2013) 281–288
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Inorganica Chimica Acta
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2-(1-Aryliminoethyl)cycloheptapyridylpalladium complexes: Synthesis,
characterization and the use in the Heck-reaction
Bin Ye a,b, Lin Wang , Xinquan Hu a, , Carl Redshaw c, , Wen-Hua Sun b,
b
⇑
⇑
⇑
a
College of Chemical Engineering and Materials Science, Zhejiang University of Technology, Hangzhou 310014, China
Key laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
Department of Chemistry, University of Hull, Hull HU6 7RX, UK
b
c
a r t i c l e i n f o
a b s t r a c t
Article history:
Received 27 June 2013
Received in revised form 2 August 2013
Accepted 7 August 2013
Available online 17 August 2013
A series of 2-(1-aryliminoethyl)cycloheptapyridine derivatives (L1–L7) were prepared in good yield by
the condensation reaction of 2-acetylcycloheptapyridine with various anilines, and then reacted with
PdCl (CH CN) in dichloromethane to form the respective palladium(II) complexes (C1–C7). All organic
2 3 2
and palladium compounds were characterized by FT-IR and NMR spectroscopy, as well as by elemental
analysis. The molecular structures of the complexes C4, C5 and C7 were determined by single crystal
X-ray diffraction studies and revealed distorted square geometries at each palladium center via the coor-
dination of two nitrogen atoms and two chlorides. All palladium complexes exhibited good activity in the
Heck cross-coupling reaction between bromoarenes and styrene, and the catalytic systems possessed
high thermal stability.
Keywords:
2
-(1-Aryliminoethyl)cycloheptapyridine
Palladium complex
Molecular structure
Heck reaction
Ó 2013 Elsevier B.V. All rights reserved.
1
. Introduction
The Heck reaction has remained an effective methodology in
reaction [39,40]. With this in mind, a new series of heterocyclic
compounds has been used as ligands in palladium complexes,
which were then screened in the Heck reaction. In particular, 2-
(1-aryliminoethyl)cycloheptapyridine derivatives (L1–L7) and
their palladium(II) complexes (C1–C7) have been synthesized
herein and fully characterized. The trial of these palladium com-
plexes in ethylene polymerization revealed low activity, fortu-
nately though high activities have been observed for these
palladium complexes in the Heck cross-coupling reaction of aryl
halides with olefins. Herein, the synthesis and characterization of
2-(1-aryliminoethyl)cycloheptapyridine derivatives (L1–L7) and
their palladium(II) complexes (C1–C7) are reported and are dis-
cussed along with their use in the Heck cross-coupling reaction.
carbon–carbon bond formation over the past four decades [1], as
highlighted by the numerous review articles and book chapters
[
2–6]. Indeed, such coupling reactions have been widely used to
synthesize fine chemicals, drug intermediates, natural products,
bioactive compounds, UV absorbers, antioxidants by the chemical
industry. [7–11] This wide application is made possible because
the Heck reaction is commonly used under mild conditions and
can tolerate various functional groups [12,13]. In regard to the pal-
ladium complexes used for carbon-coupling reactions, the elec-
tronic and steric influence of the substituents is more significant
in the Heck reaction [14–16] than for the Sonogashira–Hagihara
[
17,18], or Suzuki–Miyaura [19–22] reactions. Recently, attempts
2
. Results and discussion
have been made to employ non-phosphine ligands by using vari-
ous nitrogen-based heterocyclic compounds [23–25], and a num-
ber of palladium complexes have been prepared using bi-dentate
N,N-ligands such as diimine [26], dipyridine [27–32] and hydra-
zone [33] derivatives. However, despite the successful deployment
of iminopyridylpalladium complex pre-catalysts for olefin poly-
merization [34–37] as well as their biological interest [38], such
palladium complexes have not been well explored for the Heck
2.1. Synthesis and characterization of the ligands and complexes
The synthesis of 2-acetylcycloheptapyridine was achieved in
high yield using the Stille coupling reaction [41] of 2-chlorocyclo-
heptapyridine with tributyl(1-ethoxyvinyl)tin (Scheme 1). Further
condensation reactions of 2-acetyl-cycloheptapyridine with vari-
ous anilines in toluene afforded the corresponding 2-(1-arylimino-
ethyl)cycloheptapyridine derivatives (L1–L7) in moderate to good
isolated yield (57–80%). Further reaction of the 2-(1-aryliminoeth-
yl) cycloheptapyridine derivatives (L1–L7) with PdCl (CH CN) in
2 3 2
dichloromethane afforded the title complexes, 2-(1-aryliminoeth-
yl)cycloheptapyridylpalladium complexes (C1–C7, Scheme 1). All
⇑
Corresponding authors. Tel.: +86 10 62557955; fax: +86 10 62618239 (W.-H.
Sun).
E-mail addresses: c.redshaw@hull.ac.uk (C. Redshaw), whsun@iccas.ac.cn (W.-H.
Sun).
0
020-1693/$ - see front matter Ó 2013 Elsevier B.V. All rights reserved.
http://dx.doi.org/10.1016/j.ica.2013.08.008

2
82
B. Ye et al. / Inorganica Chimica Acta 407 (2013) 281–288
Bu SnCH(Me)OEt
3
Ar-NH2
p-TsOH, Toluene
Pd(dppf)Cl2
N
Cl
N
N
1
,4-dioxane
O
N
R1
L1-L7
Ar
PdCl (CH CN)
CH Cl2
2
2
3
2
Ar =
R2
R1
L1 L2 L3 L4 L5
C1 C2 C3 C4 C5
L6
C6
L7
C7
N
Pd
Cl
C1-C7
N
R1
R
Et iPr Me Et CH(Ph) CH(Ph)2
Cl
Ar
Me
H
2
2
H
H
Me Me
Me
Cl
Scheme 1. Synthetic procedure.
the organic compounds and complexes were fully characterized by
FT-IR and NMR spectroscopic measurements and by elemental
analysis. According to their FT-IR spectra, the vC@N stretching
À1
frequencies have been shifted to higher field at about 1580 cm
and with a slightly weaker intensity for the coordinated palladium
À1
complexes in the comparison to 1641–1645 cm for the corre-
sponding organic compounds, consistent with previous observa-
13
tions for related palladium species [42]. In the
C NMR
measurements, the d C@N groups in the palladium complexes are
shifted to lower field, for example 178.0 ppm for C2 versus
1
N
67.3 ppm for L2, indicating strong coordination between the
imino and Pd centers [43]. Moreover, the molecular structures of
the palladium complexes C4, C5 and C7 have been confirmed by
single crystal X-ray diffraction studies.
Fig. 2. ORTEP drawing of C5. Thermal ellipsoids are shown at the 30% probability
2.2. Crystal and molecular structures
level. Hydrogen atoms have been omitted for clarity.
Single crystals of the complexes C4, C5 and C7 were individually
obtained by slow diffusion of diethyl ether into their dichloro-
methane solutions at ambient temperature. All the palladium com-
plexes C4, C5 and C7 revealed a distorted square planar geometry
at palladium, with the metal coordinated by two nitrogen atoms of
the chelating ligand and two chlorides. The molecular structures
are shown in the Figs. 1–3, with selected bond lengths and angles
tabulated in Table 1. According to the data in Table 1, all three pal-
ladium complexes showed similar square planar geometry around
the palladium center. The phenyl planes linked on the imino-group
are almost perpendicular to the coordination plane Pd1, N1 and N2
with slight differences of the dihedral angles at 82.63° in C4, 87.33°
in C5 and 86.86° in C7, respectively. However, the influence of the
substituents could be significantly observed when considering
their bulk. For example, assigning two coordination planes as one
of Pd1, N1 and N2 atoms and the other as the Pd1, Cl1, and Cl2
Fig. 3. ORTEP drawing of C7. Thermal ellipsoids are shown at the 30% probability
level. Hydrogen atoms have been omitted for clarity.
atoms, their dihedral angles are 9.80° in C4, 12.94° in C5 and
1
5.39° in C7, indicating the larger dihedral angle is caused by the
space demands of the bulky substituents within the ligands used.
The C@N double-bond character is revealed by the N2–C2 lengths
at 1.290 Å in C4, 1.293 Å in C5 and 1.292 Å in C7; the Pd–Nimino
bond lengths are shorter than the Pd–Npyridyl bonds, as illustrated
by the stronger Pd–Nimino (2.028(6) in C4, 2.032(3) in C5 and
2
.025(3) Å in C7) versus Pd–Npyridyl (2.118(6) in C4, 2.059(3) in
C5 and 2.108(2) Å in C7), respectively; i.e. weaker coordination oc-
curred between the palladium with an sp -nitrogen within the
Fig. 1. ORTEP drawing of C4. Thermal ellipsoids are shown at the 30 % probability
level. Hydrogen atoms have been omitted for clarity.
2

B. Ye et al. / Inorganica Chimica Acta 407 (2013) 281–288
283
Table 1
tabulated in Table 2. Inspired by the literature [45], N,N-dimethyl-
acetamide (DMA) appears to be the preferred solvent and was used
to select a suitable base (entries 1–10, Table 2). Illustrated by the
observations in entries 1 and 2 with the base sodium carbonate,
the current system preferred elevated reaction temperatures; trace
amounts of bromobenzene were converted over 24 h at 120 °C (en-
try 1), while 71% of bromobenzene was converted over 24 h at
Selected bond lengths (Å) and angles (°) for the complexes C4, C5 and C7.
C4
C5
C7
Bond lengths
Pd(1)–N(1)
Pd(1)–N(2)
Pd(1)–Cl(1)
Pd(1)–Cl(2)
N(1)–C(3)
N(1)–C(7)
N(2)–C(2)
N(2)–C(13)
2.118(6)
2.028(6)
2.262(2)
2.307(2)
1.385(9)
1.321(9)
1.290(10)
1.444(10)
2.059(3)
2.032(3)
2.2654(10)
2.3065(9)
1.370(4)
1.336(4)
1.293(4)
1.437(4)
2.108(2)
2.025(3)
2.2755(8)
2.3044(8)
1.377(4)
1.350(4)
1.292(4)
1.443(4)
1
50 °C (entry 2). On varying the base (entries 2–10), the catalytic
system with NaHCO was found to exhibit 92% bromobenzene con-
version (entry 10). On optimizing the influence of solvent (entries
0–17), N,N-dimethylformamide (DMF) was found to be the best
choice (entry 14). It is necessary to conduct the reaction over
3
1
Bond angles
N(1)–Pd(1)–N(2)
N(1)–Pd(1)–Cl(1)
N(1)–Pd(1)–Cl(2)
N(2)–Pd (1)–Cl(1)
N(2)–Pd(1)–Cl(2)
Cl(1)–Pd(1)–Cl(2)
79.7(2)
79.77(11)
173.64(8)
96.81(8)
93.93(9)
166.69(8)
89.51(4)
80.22(10)
167.53(6)
102.33(7)
91.22(7)
167.73(7)
87.96(3)
2
1
4 h (entry 10) due to the relatively low conversion rates (entry
8). Moreover, it proved possible to reduce the amount of the pal-
171.68(17)
101.64(17)
92.52(19)
170.71(19)
86.53(8)
ladium catalyst used (entry 19) by about a half, whilst still main-
taining high efficiency (entry 14).
Under the optimized conditions, 1.2 equivalents of styrene and
1
.1 equivalents of NaHCO
3
to bromobenzene with the [Pd]/[bro-
À5
mobenzene] at 2 Â 10 at 150 °C for 24 h in DMF, all palladium
complexes were explored for the Heck coupling reaction (Table 3).
In general, similar activities were observed, however, slight differ-
ences were revealed such that there was a trend for bulky substit-
uents to cause lower activities for their palladium catalysts: Me
conjugated aryl ring. The Pd–Cl lengths in the complexes C4, C5
and C7 exhibit typical bond lengths [43,44].
2.3. Catalytic behavior
(
for C1) > Et (for C2) > i-Pr (for C3) (entries 1–3). With an additional
Initially, complexes C1–C7 were screened in ethylene polymer-
methyl group present for the ligands in C4 and C5, better catalytic
activities were achieved because of higher solubility (entries 4 and
5). However, the complexes C6 and C7 bearing ligands with bulky
benzhydryl-substituents also showed high activities, for which the
slight difference is attributed to the para-substituted methyl (entry
6) or chloride (entry7).
The Heck reaction with various aryl halides was explored using
the complex C5, and results are summarized in Table 4; indicating
the possibility for all bromoarenes. It appeared that electron with-
drawing para-substituents on the bromoarenes enhanced the
ization, however results were poor and so the focus of our screen-
ing program switched to the Heck coupling reaction. Complex C5
was used to optimize the reaction conditions for the typical Heck
reaction of bromobenzene and styrene (affording 1,2-diphenyleth-
ene), including variation of solvent and base used. By employing a
slight excess (1.2 equivalent) of styrene and 1.1 equivalent of base
to bromobenzene in the presence of a catalytic amount ([Pd]/
À5
[
bromobenzene] = 4 Â 10 ) of C5 and different solvents, the
conversion of bromobenzene was monitored and the results are
Table 2
a
Optimization of bromobenzene and styrene using complex C5.
Br
C5
1
.1mol% base
Solvent
+
Conversion (%)b
TOF (h )c
À1
Entry
Base
Solvent
Temp (°C)
Time (h)
1
2
3
4
5
6
7
8
9
Na
Na
2
CO
CO
3
3
DMA
DMA
DMA
DMA
DMA
DMA
DMA
DMA
DMA
DMA
toluene
120
150
150
150
150
150
150
150
150
150
110
100
150
150
150
80
24
24
24
24
24
24
24
24
24
24
24
24
24
24
24
24
24
12
24
trace
71
73
55
65
trace
trace
trace
trace
92
trace
trace
78
–
2
740
760
570
670
–
–
–
–
960
–
K
2
CO
3
NaOAc
NaOH
Et
Na
NaF
CaF
3
N
3
PO
4
2
1
1
1
1
1
1
1
1
1
0
1
2
3
4
5
6
7
NaHCO
NaHCO
NaHCO
NaHCO
NaHCO
NaHCO
NaHCO
NaHCO
NaHCO
NaHCO
3
3
3
3
3
3
3
3
3
3
1,4-dioxane
–
d
DMA/H
DMF
2
O
810
1030
970
–
–
1600
2020
99
93
trace
trace
77
DMF/H
CH CN
THF
2
Od
3
60
150
150
8
DMF
DMF
e
1
9
97
a
b
c
À8
Reaction conditions: 2.0 mmol bromobenzene, 2.4 mmol styrene, 2.2 mmol base, 8 Â 10 mol C5, 4.0 mL solvent.
Determined by GC.
TOF: mol bromobenzene/mol Pd h.
d
e
Mixture of proportion (10:1).
À8
4
 10 mol C5 was used.

2
84
B. Ye et al. / Inorganica Chimica Acta 407 (2013) 281–288
Table 3
3
. Conclusions
a
Heck reaction of bromobenzene and styrene by C1–C7.
The newly designed 2-acetylcycloheptapyridine was effectively
Br
2
1
x10-3 mol% [Pd]
.1mol% NaHCO3
synthesized by using the Stille coupling reaction of 2-chlorocyclo-
heptapyridine and tributyl(1-ethoxyvinyl)tin. A series of 2-(1-
aryliminoethyl)cycloheptapyridine derivatives were achievable
through the condensation reactions between 2-acetylcyclohepta-
pyridine and various aniline derivatives. The 2-(1-aryliminoeth-
yl)cycloheptapyridine derivatives acted as bi-dentate ligands on
+
DMF
Conversion (%)
b
TOF (hÀ1)c
Entry
Cat.
1
2
3
4
5
6
7
C1
C2
C3
C4
C5
C6
C7
92
89
87
95
97
97
95
1920
1850
1810
1980
2020
2020
1980
2 3 2
coordination with PdCl (CH CN) . The dichloropalladium com-
plexes revealed a distorted square geometry at palladium via coor-
dination with two nitrogen atoms and two chlorides. All palladium
complexes showed good catalytic activities for the Heck coupling
between bromoarenes and styrene, and the catalytic systems pos-
sessed high thermal stability.
a
Reaction conditions: 2.0 mmol bromobenzene, 2.4 mmol styrene, 2.2 mmol
NaHCO , 4.0 mL DMF, 150 °C, 24 h.
3
b
Determined by GC.
TOF: mol bromobenzene/mol Pd h.
c
4. Experimental
4.1. General procedure and materials
Table 4
a
Heck reaction of aryl bromides and styrene using complex C5.
All manipulations of moisture-sensitive compounds were car-
ried out under an atmosphere of nitrogen using standard Schlenk
techniques. Melting points were determined using a digital elec-
trothermal apparatus without calibration. NMR spectra were re-
2
1
X10-3 mol% C5
.1mol% NaHCO3
ArBr
+
Ph
Ar
Ph
DMF
corded on a Bruker DMX 400 MHz instrument at ambient
Conversion (%)b
TOF (h )c
À1
Entry
1
ArBr
temperature using TMS as an internal standard; d values are given
in ppm and J values in Hz. The IR spectra were obtained on a Perkin
Elmer FT-IR 2000 spectrophotometer by using the KBr disc in the
97
2020
Br
À1
range of 4000–400 cm . Elemental analysis was carried out using
2
3
97
99
2020
2060
MeO
O
Br
a Flash EA 1112 microanalyzer. Conversions were determined by
CP-3800 GC.
4
4
.2. Syntheses and characterization
Br
.2.1. Synthesis of 2-acetyl-cycloheptapyridine
2
4
88
1830
O
-Chloro-cycloheptapyridine (0.1 mol, 18.1 g), tributyl(1-eth-
oxyvinyl)tin (0.11 mol, 40.0 g), Pd(dppf)Cl (3 mmol, 2.22 g), and
50 mL of chlorobenzene were added into a 500 mL three-necked
flask. The mixture was refluxed for 12 h under N , and then cooled
to room temperature. The solution was washed with KF solution
2
2
Br
2
5
6
92
33
1920
690
H C
3
Br
(
0.3 M, 100 mL Â 3) and 100 mL of 10% aqueous HCl. The resultant
solution was neutralized by aqua ammonia and extracted with
dichloromethane. The organic layer was collected and dried over
CH3
Br
2 4
anhydrous Na SO , and then concentrated in vacuo to afford the
crude product. The residue was purified by silica gel chromatogra-
phy to afford 2-acetyl-cycloheptapyridine (15.7 g, yield 83%) as a
CH3
7
54
1120
1
S
white solid. H NMR (400 MHz, CDCl
3
): d 7.75 (d, J = 8.0 Hz, 1H,
),
), 1.86–1.90 (m, 2H,
). C NMR (100 MHz, CDCl ): d
Br
Py–H,) 7.46 (d, J = 7.6 Hz, 1H, Py–H), 3.08 (t, J = 5.6 Hz, 2H, CH
.81 (t, J = 4.0 Hz, 2H, CH ), 2.68 (s, 3H, CH
CH
2
2
2
3
a
Reaction conditions: 2.0 mmol ArBr, 2.4 mmol styrene, 2.2 mmol Na
.0 mL DMF 150 °C, 24 h.
Determined by GC.
TOF: mol ArBr/mol Pd h.
2
CO
3
,
13
2
), 1.66–1.71 (m, 4H, 2 Â CH
2
3
4
b
200.6, 162. 8, 150.8, 142.5, 137.0, 119.6, 39.5, 35.5, 32.5, 27.8,
26.6, 25.8.
c
4.2.2. Synthesis of 2-(1-(2,6-
coupling reactions (entries 1–3); meanwhile methyl-substituents
on the bromoarenes deactivated the reaction (entries 1, 5, and
dimethylphenylimino)ethyl)cycloheptapyridine (L1)
2,6-Dimethylaniline (0.24 g, 2.0 mmol) was added to a solution
of 2-acetyl-cycloheptapyridine (0.19 g, 1.0 mmol) with a catalytic
amount of p-toluenesulfonic acid (0.02 g, 0.1 mmol) in 30 mL of
toluene. The mixture was stirred at reflux temperature for 6 h.
The solvent was evaporated under reduced pressure, and the resi-
due was subsequently purified by silica gel chromatography to af-
ford the light yellow solid (0.21 g, 72%). Mp: 82–83 °C. FT-IR (KBr,
6
); ortho-methyl substituents exhibited a negative effect due to
sterics, which is consistent to previous literature results [46]. A
lower activity was observed for 2-bromothiophene (entries 7),
and trace conversion of 2-bromobenzenamine and 4-bromoaniline
were achieved; this is tentatively attributed to the potential coor-
dination of their functional groups (amine and sulfur atom) to the
palladium species. All products were isolated and their identity
À1
cm ): 2921 (s), 2850 (m), 2361 (s), 2336 (w), 1643 (s), 1569 (m),
1
13
confirmed by H and C NMR spectroscopy by comparison with
literature data [47–49].
1463 (w), 1437 (s), 1358 (m), 1304 (w), 1254 (w), 1191 (m), 1161
(w), 1116 (s), 1085 (m), 1035 (w), 955 (m), 853 (w), 810 (w), 754

B. Ye et al. / Inorganica Chimica Acta 407 (2013) 281–288
285
Table 5
Crystal data and structure refinements for C4, C5 and C7.
C4
C5
C7
Empirical formula
Crystal color
Formula weight
T (K)
C
21
H
26Cl
2
N
2
Pd
C
23
H
30Cl
2
2
N Pd
44 3 2
C H39Cl N Pd
brown
808.52
173 (2)
0.71073
brown
brown
483.74
173 (2)
0.71073
511.79
173 (2)
0.71073
k (Å)
Crystal system
Space group
a (Å)
b (Å)
c (Å)
monoclinic
P2(1)/n
18.573(4)
11.581(2)
20.647(4)
90
110.77(3)
90
4152.4(14)
8
monoclinic
P2(1)/c
9.3545(19)
7.9698(16)
30.667(6)
90
97.00(3)
90
2269.3(8)
4
orthorhombic
P2(1)2(1)2(1)
11.965(2)
17.221(3)
17.751(4)
90
a
(°)
b (°)
(°)
90
90
c
3
V (Å )
3657.4(13)
4
1.468
Z
D
l
À3
calc (mg m
)
1.548
1.158
1.498
1.064
À1
(mm
)
0.762
F(000)
1968
1048
1656
Cryst size (mm)
h (°)
Limiting indices
0.26 Â 0.19 Â 0.07
1.27–27.48
À21 6 h 6 24,
À15 6 k 6 15,
À26 6 l 6 18
29370
9467 (0.0653)
99.5
none
0.44 Â 0.40 Â 0.20
2.68–27.48
À11 6 h 6 12,
À10 6 k 6 10,
À39 6 l 6 39
15021
5113 (0.0371)
98.3
none
0.39 Â 0.31 Â 0.16
2.63–27.50
À15 6 h 6 12,
À13 6 k 6 22,
À23 6 l 6 15
13153
8167 (0.0295)
99.0
none
No. of reflections collected
No. unique reflections (Rint
Completeness to h (%)
Abs corr
)
Data/restraints/params
Goodness of fit (GOF) on F
9467/0/469
1.074
5113/0/253
0.954
8167/0/451
1.073
2
Final R indices [I > 2
R indices (all data)
Largest difference in peak and hole (e Å
r
(I)]
R
R
1
= 0.0715, wR
= 0.0901, wR
2
= 0.1775
= 0.2205
R
R
1
= 0.0426, wR
= 0.0473, wR
2
2
= 0.1360
= 0.1455
R
R
1
= 0.0362, wR
= 0.0377, wR
2
2
= 0.0844
= 0.0856
1
2
1
1
À3
)
1.112 and À1.059
1.063 and À0.706
0.774 and À0.717
(
s), 712 (w), 686 (m). 1H NMR (400 MHz, CDCl
3
): d 8.07 (d,
1077 (w), 956 (w), 931 (w), 860 (w), 820 (m), 761 (s), 697 (m),
1
J = 8.0 Hz, 1H, Py–H), 7.47 (d, J = 7.6 Hz, 1H, Py–H), 7.05 (d,
J = 7.6 Hz, 2H, 2 Â Ar–H), 6.90 (t, J = 7.6 Hz, 1H, Ar–H), 3.10 (t,
669 (w). H NMR (400 MHz, CDCl
H,) 7.49 (d, J = 7.6 Hz, 1H, Py–H), 7.16 (d, J = 0.8 Hz, 2H, 2 Â Ar–
H), 7.07 (t, J = 8.4 Hz, 1H, Ar–H), 3.11 (t, J = 5.6 Hz, 2H, CH ), 2.85
(t, J = 3.6 Hz, 2H, CH
), 2.78–2.73 (m, 2H, 2 Â CH), 2.20 (s, 3H,
CH ), 1.92–1.89 (m, 2H, CH ), 1.15 (d,
), 1.78–1.70 (m, 4H, 2 Â CH
): d 167.3,
3
): d 8.09 (d, J = 8.0 Hz, 1H, Py–
J = 5.6 Hz, 2H, CH
2
), 2.84 (t, J = 5.6 Hz, 2H, CH
2
), 2.16 (s, 3H, CH
), 1.75–1.70 (m, 4H,
): d 167.6, 162.2, 153.3,
49.1, 139.7, 137.1, 136.9, 128.0, 127.8, 125.6, 118.8, 39.7, 35.3,
2.7, 28.0, 26.7, 18.0, 16.7. Anal. Calc. for C20 (292): C,
3
),
2
2
2
1
3
8
.03 (s, 6H, 2 Â CH
3
), 1.92–1.88 (m, 2H, CH
2
2
1
3
 CH
2
).
C NMR (100 MHz; CDCl
3
3
2
2
1
3
J = 7.6 Hz, 12H, 4 Â CH
3 3
). C NMR (100 MHz; CDCl
H
24
N
2
162.2, 153.3, 146.9, 139.6, 137.1, 136.0, 123.4, 123.0, 118.8, 39.7,
2.15; H, 8.27; N, 9.58. Found: C, 82.20; H, 8.36; N, 9.52%.
35.4, 32.7, 28.3, 28.0, 26.7, 23.4, 23.1, 17.4. Anal. Calc. for
24 32 2
C H N (348): C, 82.71; H, 9.25; N, 8.04. Found: C, 82.64; H,
4.2.3. Synthesis of 2-(1-(2,6-
9.25; N, 8.01%.
diethylphenylimino)ethyl)cycloheptapyridine (L2)
Using the same procedure as for the synthesis of L1, L2 was ob-
tained as a light yellow oil (0.24 g, 75%). FT-IR (KBr, cm ): 2964
4.2.5. Synthesis of 2-(1-(2,4,6-
À1
trimethylphenylimino)ethyl)cycloheptapyridine (L4)
Using the same procedure as for the synthesis of L1, L4 was ob-
tained as a light yellow solid (0.22 g, 72%). Mp: 92–93 °C. FT-IR
(
1
(
(
(
w), 2925 (s), 2851 (s), 1644 (s), 1589 (w), 1569 (m), 1458 (s),
400 (w), 1363 (s), 1306 (m), 1280 (w), 1255 (w), 1192 (s), 1160
w), 1118 (s), 1074 (w), 958 (m), 869 (w), 851 (w), 823 (w), 803
w), 767 (s), 695 (s), 664 (w). 1H NMR (400 MHz, CDCl
): d 8.14
d, J = 7.6 Hz, 1H, Py–H), 7.50 (d, J = 8.0 Hz, 1H, Py–H), 7.14 (d,
À1
(KBr, cm ): 2925 (s), 2851 (w), 2361 (s), 2335 (w), 1642 (s),
3
1571 (m), 1478 (w), 1441 (s), 1403 (w), 1359 (s), 1306 (w), 1278
(w), 1216 (s), 1191 (m), 1146 (w), 1119 (s), 1074 (w), 1033 (w),
1011 (w), 957 (m), 930 (w), 852 (s), 827 (w), 787 (m), 712 (w),
J = 7.6 Hz, 2H, 2 Â Ar–H), 7.05 (t, J = 7.6 Hz, 1H, Ar–H), 3.15 (t,
J = 4.2 Hz, 2H, CH ), 2.86 (t, J = 4.0 Hz, 2H, CH ), 2.52–2.44 (m, 4H,
), 2.24 (s, 3H, CH ), 1.95–1.91 (m, 2H, CH ), 1.79–1.74 (m,
H, 2 Â CH ), 1.18 (t, J = 7.4 Hz, 6H, 2 Â CH ). C NMR (100 MHz;
): d 167.3, 162.2, 153.3, 148.2, 139.7, 137.1, 137.0, 131.4,
25.9, 123.2, 118.8, 39.7, 35.4, 32.7, 28.0, 26.7, 24.7, 17.1, 13.8,
3.7. Anal. Calc. for C22 (320): C, 82.45; H, 8.81; N, 8.74.
1
2
2
687 (w). H NMR (400 MHz, CDCl3): d 8.06 (d, J = 8.0 Hz, 1H, Py–
2
4
 CH
2
3
2
H,) 7.47 (d, J = 8.0 Hz, 1H, Py–H), 6.87 (s, 2H, 2 Â Ar–H), 3.10 (t,
13
2
3
J = 4.0 Hz, 2H, CH
2
), 2.83 (t, J = 4.0 Hz, 2H, CH
2
), 2.28 (s, 3H, CH
3
),
),
CDCl
3
2.16 (s, 3H, CH
3
), 1.99 (s, 6H, 2 Â CH
3
), 1.92–1.88 (m, 2H, CH
2
1
3
1
1
1.76–1.69 (m, 4H, 2 Â CH
2
). C NMR (100 MHz; CDCl
3
): d 167.9,
H
28
N
2
162.2, 153.4, 146.6, 139.6, 137.1, 136.9, 131.9, 128.6, 125.5,
Found: C, 82.50; H, 8.75; N, 8.56%.
118.8, 39.7, 35.4, 32.7, 28.0, 26.7, 20.8, 18.0, 16.7. Anal. Calc. for
21 26 2
C H N (306): C, 82.31; H, 8.55; N, 9.14. Found: C, 82.00; H,
4.2.4. Synthesis of 2-(1-(2,6-
8.52; N, 9.26%.
diisopropylphenylimino)ethyl)cycloheptapyridine (L3)
Using the same procedure as for the synthesis of L1, L3 was ob-
4.2.6. Synthesis of 2-(1-(2,6-diethyl-4-
tained as a light yellow solid (0.28 g, 80%). Mp: 108–109 °C. FT-IR
methylphenylimino)ethyl)cycloheptapyridine (L5)
À1
(
KBr, cm ): 2956 (w), 2924 (s), 2855 (w), 2361 (s), 2336 (w),
Using the same procedure as for the synthesis of L1, L5 was ob-
1
645 (s), 1570 (m), 1460 (s), 1436 (s), 1381 (w), 1363 (w), 1324
tained as a light yellow solid (0.26 g, 78%). Mp: 78–79 °C. FT-IR
(KBr, cm ): 2967 (w), 2923 (s), 2852 (w), 2361 (s), 2336 (w),
À1
(
w), 1309 (m), 1280 (w), 1242 (w), 1190 (s), 1160 (w), 1120 (s),

2
86
B. Ye et al. / Inorganica Chimica Acta 407 (2013) 281–288
1
1
8
641 (s), 1570 (m), 1461 (s), 1441 (s), 1359 (s), 1306 (w), 1209 (w),
(t, J = 5.4 Hz, 2H, CH
1.90–1.85 (m, 4H, 2 Â CH
(100 MHz; CD Cl ): d 178.8, 171.5, 153.5, 147.2, 143.9, 139.8,
130.3, 128.0, 127.5, 125.2, 40.4, 36.1, 31.7, 27.9, 27.6, 18.4, 18.4.
Anal. Calc. for C20 Pd (469): C, 51.14; H, 5.15; N, 5.96.
2
), 2.32(s, 6H, 2 Â CH
3
), 2.14 (s, 3H, CH
3
),
13
191 (m), 1146 (w), 1119 (s), 1075 (m), 955 (m), 885 (w), 858 (s),
2
), 1.77–1.74 (m, 2H, CH
2
). C NMR
25 (w), 805 (w), 783 (w), 692 (w), 669 (w). 1H NMR (400 MHz,
2
2
CDCl
H), 6.91 (s, 2H, 2 Â Ar–H), 3.10 (t, J = 5.6 Hz, 2H, CH
J = 4.0 Hz, 2H, CH ), 2.34 (s, 3H, CH
), 1.76–1.70 (m, 4H,
3
): d 8.06 (d, J = 8.0 Hz, 1H, Py–H), 7.47 (d, J = 8.0 Hz, 1H, Py–
), 2.83 (t,
),
2
2 2
H24Cl N
2
), 2.38–2.28 (m, 4H, 2 Â CH
2
3
Found: C, 51.12; H, 5.21; N, 6.14%.
2
.17 (s, 3H, CH
 CH ), 1.11 (t, J = 7.6 Hz, 6H, 2  CH
): d 167.5, 162.1, 153.4, 145.6, 137.1, 136.9, 132.2, 131.3,
26.7, 118.7, 39.7, 35.4, 32.7, 28.0, 24.6, 21.1, 17.0, 14.2, 13.9. Anal.
Calc. for C23 (334): C, 82.59; H, 9.04; N, 8.37. Found: C, 83.07;
H, 8.96; N, 8.16%.
3
), 1.93–1.88 (m, 2H, CH
2
13
2
CDCl
1
2
3
). C NMR (100 MHz;
4.2.10. Synthesis of 2-(1-(2,6-
diethylphenylimino)ethyl)cycloheptapyridyl palladium(II) chloride
(C2)
3
H
30
N
2
Using the above procedure for C1, C2 was isolated as a yellow
À1
solid in 84% yield. FT-IR (KBr, cm ): 2922 (s), 2855 (w), 1610
(
w), 1585 (s), 1437 (s), 1405 (m), 1369 (m), 1329 (m), 1289 (m),
4
.2.7. Synthesis of 2-(1-(2,6-dibenzhydryl-4-
1245 (m), 1201 (s), 1142 (w), 1097 (w), 1065 (w), 952 (m), 842
(w), 810 (s), 777 (s), 730 (w), 661 (m). H NMR (400 MHz, CDCl ):
3
1
methylphenylimino)ethyl)cycloheptapyridine (L6)
Using the same procedure as for the synthesis of L1, L6 was ob-
d 7.83 (d, J = 7.2 Hz, 1H, Py–H), 7.71 (d, J = 7.6 Hz, 1H, Py–H), 7.28 (t,
J = 7.6 Hz, 1H, Ar–H), 7.15 (d, J = 7.2 Hz, 2H, 2 Â Ar–H), 3.76 (t,
tained as a light yellow solid (0.35 g, 57%). Mp: 210–211 °C. FT-IR
À1
(
1
1
KBr, cm ): 2919 (s), 2849 (w), 1641 (s), 1600 (w), 1571 (m),
J = 4.2 Hz, 2H, CH
CH
2 Â CH
2
), 2.95 (t, J = 4.0 Hz, 2H, CH
2
), 2.90–2.83 (m, 2H,
), 1.90–1.85 (m, 4H,
), 1.29 (t, J = 7.4 Hz, 6H, 2 Â CH ).
): d 178.0, 171.7, 153.3, 146.9, 142.6,
139.5, 135.1, 127.9, 125.4, 124.6, 40.5, 36.1, 31.6, 27.6, 27.5, 24.3,
18.8, 13.2. Anal. Calc. for C22 Pd (497): C, 53.08; H, 5.67;
493 (m), 1445 (s), 1361 (w), 1309 (w), 1240 (m), 1213 (w),
2
), 2.50–2.44 (m, 2H, CH
), 1.77–1.73 (m, 2H, CH
C NMR (100 MHz; CDCl
2 3
), 2.14 (s, 3H, CH
193 (w), 1121 (m), 1075 (w), 1029 (w), 853 (w), 827 (w), 770
2
2
3
1
13
(
s), 746 (m), 697 (s). H NMR (400 MHz, CDCl
3
): d 7.76 (d,
3
J = 8.0 Hz, 1H, Py–H), 7.43 (d, J = 7.6 Hz, 1H, Py–H), 7.36–6.92 (m,
2
(
CH
3
1
1
1
0H, 20 Â Ar–H), 6.78 (s, 2H, 2 Â Ar–H), 5.40 (s, 2H, 2 Â CH), 3.11
t, J = 4.8 Hz, 2H, CH ), 2.87 (t, J = 4.8 Hz, 2H, CH ), 2.24 (s, 3H,
), 1.22 (s,
): d 162.0, 153.2, 146.6,
2 2
H28Cl N
2
2
N, 5.63. Found: C, 52.98; H, 5.77; N, 5.49%.
3
), 1.98–1.94 (m, 2H, CH
2
), 1.78–1.72 (m, 4H, 2 Â CH
2
1
3
H, CH
3
).
C NMR (100 MHz; CDCl
3
4.2.11. Synthesis of 2-(1-(2,6-
diisopropylphenylimino)ethyl)cycloheptapyridyl palladium(II)
chloride (C3)
44.0, 143.0, 139.3, 136.7, 132.5, 131.4 130.1, 129.7, 128.7, 128.4,
28.1, 126.2, 126.1, 118.9, 52.1, 39.7, 35.4, 32.7, 28.1, 26.8, 21.5,
7.3. Anal. Calc. for C45
42
H N
2
(610): C, 88.48; H, 6.93; N, 4.59.
Using the procedure for C1, C3 was isolated as a yellow solid in
À1
Found: C, 88.47; H, 7.07; N, 4.38%.
82% yield. FT-IR (KBr, cm ): 2957 (w), 2921 (s), 2861 (w), 1609
(
w), 1584 (s), 1440 (s), 1404 (m), 1363 (m), 1321 (m), 1292 (w),
4
.2.8. Synthesis of 2-(1-(2,6-dibenzhydryl-4-
1249 (w), 1198 (w), 1180 (w), 1098 (w), 1057 (w), 957 (m), 830
(w), 800 (s), 773 (s), 726 (m). H NMR (400 MHz, CDCl ): d 7.78
3
1
chlorophenylimino)ethyl)cycloheptapyridine (L7)
Using the same procedure as for the synthesis of L1, L7 was ob-
(d, J = 8.0 Hz, 1H, Py–H,), 7.60 (d, J = 8.0 Hz, 1H, Py–H), 7.32 (t,
J = 7.8 Hz, 1H, Ar–H), 7.19 (d, J = 8.0 Hz, 2H, 2 Â Ar–H), 3.78 (t,
tained as a light yellow solid (0.40 g, 63%). Mp: 212–213 °C. FT-IR
À1
(
1
(
(
(
(
KBr, cm ): 2921 (s), 2848 (w), 1642 (s), 1570 (m), 1493 (m),
2H, CH
2.16 (s, 3H, CH
CH
), 1.44 (d, J = 6.8 Hz, 6H, 2 Â CH
2 Â CH
147.4, 141.2, 140.5, 139.5, 128.3, 124.9, 123.7, 40.2, 36.2, 31.7,
28.9, 27.9, 27.6, 23.7, 23.6, 19.8. Anal. Calc. for C24 Pd
2
), 3.20–3.13 (m, 2H, 2 Â CH), 2.96 (t, J = 5.4 Hz, 2H, CH
2
)
441 (s), 1365 (w), 1309 (w), 1260 (m), 1182 (s), 1121 (m), 1075
m), 1027 (s), 955 (w), 926 (w), 889 (w), 862 (w), 792 (w), 770
w), 743 (w), 696 (s), 659 (m). 1H NMR (400 MHz, CDCl
): d 7.61
3
), 1.91–1.87 (m, 4H, 2 Â CH
), 1.11 (d, J = 7.2 Hz, 6H,
3 2 2
). C NMR (100 MHz; CD Cl ): d 178.7, 171.7, 153.5,
2
), 1.78–1.75 (m, 2H,
2
3
13
3
d, J = 8.0 Hz, 1H, Py–H), 7.36 (d, J = 8.0 Hz, 1H, Py–H), 7.25–6.98
m, 20H, 20 Â Ar–H), 6.83 (s, 2H, 2 Â Ar–H), 5.26 (s, 2H, 2 Â CH),
2 2
H32Cl N
3
(
.02 (t, J = 5.4 Hz, 2H, CH
2
), 2.81 (t, J = 5.2 Hz, 2H, CH
2
), 1.91–1.87
(525): C, 54.82; H, 6.13; N, 5.33. Found: C, 54.52; H, 5.99; N, 5.05%.
1
3
m, 2H, CH
2
), 1.72–1.67 (m, 4H, 2 Â CH
2
), 1.08 (s, 3H, CH
3
).
C
NMR (100 MHz; CDCl
3
): d170.7, 162.1, 152.7, 147.5, 143.0, 142.0,
39.6, 136.7, 134.7, 129.9, 129.5, 128.5, 128.3, 128.0, 127.8,
26.5, 126.4, 118.9, 52.0, 39.6, 35.4, 32.7, 28.0, 26.7, 17.3. Anal.
39ClN (631): C, 83.54; H, 6.20; N, 4.53. Found: C,
3.08; H, 6.34; N, 4.33%.
4.2.12. Synthesis of 2-(1-(2,4,6-
trimethylphenylimino)ethyl)cycloheptapyridyl palladium(II) chloride
(C4)
1
1
Calc. for C44
H
2
Using the procedure for C1, C4 was isolated as a yellow solid in
À1
8
85% yield. FT-IR (KBr, cm ): 2910 (s), 2850 (w), 1609 (w), 1584 (s),
1
437 (s), 1403 (m), 1372 (w), 1323 (m), 1292 (m), 1247 (w), 1213
4
.2.9. Synthesis of 2-(1-(2,6-
(w), 1122 (w), 1096 (w), 1031 (w), 957 (s), 856 (s), 838 (s), 732 (m).
H NMR (400 MHz, CDCl ): d 7.76 (d, J = 5.4 Hz, 1H, Py–H,), 7.56 (d,
3
1
dimethylphenylimino)ethyl)cycloheptapyridyl palladium(II) chloride
C1)
The ligand L1 (0.14 g, 0.48 mmol) and PdCl
.40 mmol) were dissolved in 8 mL dichloromethane. The reaction
(
J = 5.4 Hz, 1H, Py–H), 6.95 (s, 2H, 2 Â Ar–H), 3.10 (t, J = 4.0 Hz, 2H,
2
(CH
3
CN)
2
(0.10 g,
CH
2
), 2.83 (t, J = 4.0 Hz, 2H, CH
), 1.99 (s, 6H, 2 Â CH ), 1.92–1.87 (m, 2H, CH
). C NMR (100 MHz; CD Cl ): d 179.1, 171.9, 154.0,
147.5, 142.0, 140.0, 137.8, 130.4, 129.1, 125.3, 40.8, 36.5, 32.1,
28.3, 28.0, 21.3, 18.7, 18.7. Anal. Calc. for C21 Pd (483): C,
2
), 2.28 (s, 3H, CH
3
), 2.16 (s, 3H,
0
CH
3
3
2
), 1.74–1.70 (m,
1
3
mixture was stirred for 20 h. The reaction volume was reduced to
about 1 mL by removing the solvent in vacuo, and then 15 mL ether
was poured into the mixture to precipitate the complex. After stir-
ring for 1 h, the yellow precipitate was collected by filtration,
washed with diethyl ether (3 Â 10 mL), and dried at room temper-
4H, 2 Â CH
2
2
2
2 2
H26Cl N
52.14; H, 5.42; N, 5.79. Found: C, 52.07; H, 5.37; N, 5.48%.
À1
ature to afford the yellow solid (0.16 g, 85%). FT-IR (KBr, cm ):
4.2.13. Synthesis of 2-(1-(2,6-diethyl-4-
2
919 (s), 2855 (w), 1609 (s), 1581 (s), 1466 (m), 1442 (m), 1402
methylphenylimino)ethyl)cycloheptapyridyl palladium(II) chloride
(C5)
(
s), 1373 (w), 1334 (s), 1317 (w), 1288 (w), 1243 (w), 1207 (s),
1
6
160 (w), 1095 (m), 1034 (w), 849 (m), 828 (s), 795 (s), 731 (m),
Using the procedure for C1, C5 was isolated as a yellow solid in
84% yield. FT-IR (KBr, cm ): 2963 (w), 2913 (s), 2852 (m), 1606
1
À1
61 (w). H NMR (400 MHz, CDCl
3
): d 7.78 (d, J = 7.6 Hz, 1H, Py–
H), 7.60 (d, J = 7.6 Hz, 1H, Py–H), 7.16 (t, J = 4.2 Hz, 1H, Ar–H),
.09 (d, J = 7.2 Hz, 2H, 2 Â Ar–H), 3.78 (t, J = 5.6 Hz, 2H, CH ), 2.95
(w), 1579 (s), 1456 (s), 1404 (s), 1371 (m), 1326 (m), 1291 (m),
1246 (w), 1198 (s), 1097 (w), 1065 (w), 1000 (w), 955 (s), 856
7
2

B. Ye et al. / Inorganica Chimica Acta 407 (2013) 281–288
287
1
(
1
(
2
s), 832 (s), 736 (w). H NMR (400 MHz, CDCl
3
): d 7.76 (d, J = 7.6 Hz,
H, Py–H,) 7.57 (d, J = 8.0 Hz, 1H, Py–H), 6.94 (s, 2H, 2 Â Ar–H), 3.77
), 2.95 (t, J = 4.0 Hz, 2H, CH ), 2.86–2.80 (m,
), 2.46–2.41 (m, 2H, CH ), 2.32 (s, 3H, CH ), 2.12 (s, 3H,
), 1.88–1.83 (m, 4H, 2 Â CH ), 1.77–1.74 (m, 2H, CH ), 1.26 (t,
). C NMR (100 MHz; CDCl ): d 178.7,
71.3, 153.3, 146.7, 140.3, 139.8, 137.3, 134.9, 126.1, 125.1, 40.4,
6.1, 31.6, 27.6, 27.4, 24.2, 21.5, 18.9, 13.3. Anal. Calc. for C23
Pd (511): C, 53.97; H, 5.91; N, 5.47. Found: C, 53.78; H, 5.66; N,
4.4. X-ray crystallographic studies
t, J = 5.6 Hz, 2H, CH
2
2
Single crystals of complexes C4, C5 and C7 suitable for X-ray dif-
fraction were grown by slow diffusion of diethyl ether into dichlo-
romethane solutions at room temperature. X-ray studies were
carried out on a Rigaku Saturn724 + CCD with graphite-monochro-
H, CH
2
2
3
CH
3
2
2
13
J = 7.6 Hz, 6H, 2 Â CH
3
3
1
3
N
matic Mo Ka radiation (k = 0.71073 Å) at 173(2) K; cell parameters
H30Cl2-
were obtained by global refinement of the positions of all collected
reflections. Intensities were corrected for Lorentz and polarization
effects and empirical absorption. The structures were solved by di-
2
5
.19%.
2
rect methods and refined by full-matrix least squares on F . All
hydrogen atoms were placed in calculated positions. Structure
solution and refinement were performed by using the SHELXL-97
package [50]. Details of the X-ray structure determinations and
refinements are provided in Table 5.
4
.2.14. Synthesis of 2-(1-(2,6-dibenzhydryl-4-
methylphenylimino)ethyl)cyclohepta-pyridylpalladium(II) chloride
C6)
By using the procedure for C1, C6 was isolated as a yellow solid
(
À1
in 90% yield. FT-IR (KBr, cm ): 3024 (w), 2918 (s), 2852 (w), 1602
w), 1578 (m), 1494 (m), 1445 (s), 1405 (m), 1327 (m), 1293 (w),
Acknowledgments
(
1
1
249 (w), 1190 (m), 1077 (w), 1030 (w), 749 (m), 699 (s).
NMR (400 MHz, CDCl ): d 7.59 (d, J = 7.6 Hz, 1H, Py–H), 7.34–7.05
m, 20H, 20 Â Ar–H), 6.87 (s, 2H, 2 Â Ar–H), 6.61 (d, J = 7.6 Hz,
), 2.96
), 1.91–1.87 (m, 4H,
H
This work is supported by NSFC No. 20904059. The RSC is
thanked for the award of a travel grant (to CR).
3
(
1
H, Py–H), 6.23 (s, 2H, 2 Â CH), 3.92 (t, J = 4.8 Hz, 2H, CH
2
Appendix A. Supplementary material
(
t, J = 4.8 Hz, 2H, CH
2
), 2.14 (s, 3H, CH
3
1
3
2
 CH
2
), 1.79–1.76 (m, 2H, CH
2
), À0.21 (s, 3H, CH
3
). C NMR
CCDC 945889–945891 contain the supplementary crystallo-
graphic data for palladium complexes C4, C5 and C7, respectively.
These data can be obtained free of charge from The Cambridge
Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_re-
quest/cif. Supplementary data associated with this article can be
found, in the online version, at http://dx.doi.org/10.1016/
j.ica.2013.08.008.
(
100 MHz; CD
2
Cl ): d 182.3, 171.4, 153.2, 147.1, 142.8, 140.8,
2
1
1
40.7, 139.2, 137.1, 130.2, 129.6, 128.9, 128.6, 128.0, 126.7,
26.3, 123.7, 52.3, 40.1, 36.0, 31.6, 27.8, 27.5, 21.3, 18.1. Anal. Calc.
Pd (788): C, 68.58; H, 5.37; N, 3.55. Found: C, 68.20;
H, 5.20; N, 3.50%.
2 2
for C45H42Cl N
4
.2.15. Synthesis of 2-(1-(2,6-dibenzhydryl-4-
chlorophenylimino)ethyl)cyclohepta pyridyl palladium(II) chloride
C7)
By using the procedure for C1, C7 was isolated as a yellow solid
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