Reactivity of μ-azido and μ-thiocyanato bridged Schiff base palladacycles toward aromatic N-heterocycles and phosphines

Article abstract of DOI:10.1016/j.jorganchem.2012.10.033

Reaction of μ-azido bridged Schiff base palladacycles [Pd{(4-R)C ₆H₃CHN-C₆H₃-2,6-i-Pr ₂}(μ-N₃)]₂ (R = H; OMe) with 1-methylimidazole generated different conformational mononuclear palladacycles. Complexes [Pd{(4-R)C₆H₃CHN-C₆H ₃-2,6-i-Pr₂}(μ-N₃)]₂ (R = H; OMe) reacted with bidentate 1,2-bis(4-pyridyl)-ethene to give mononuclear palladacycles. Also the reaction of [Pd{C₆H₄CHN-C ₆H₃-2,6-i-Pr₂}(μ-N₃)] ₂ with 4,4′-bipyridine (bpy) produced mononuclear palladacycles. However, the reaction of [Pd{(4-MeO)C₆H ₃CHN-C₆H₃-2,6-i-Pr₂}(μ-N ₃)]₂ with 4,4′-bipyridine formed a 4,4′-bipyridine bridged binuclear palladacycle [Pd{(4-OMe)C ₆H₃CHN-C₆H₃-2,6-i-Pr ₂}(N₃)]₂(μ-bpy). In contrast, μ-thiocyanato bridged Schiff base palladacycles were relatively unreactive toward aromatic N-heterocycles. Only the reaction of [Pd{C₆H ₄CHNC₆H₃-2,6-i-Pr₂}(μ-SCN)] ₂ with imidazole generated a thiocyanato coordinated mononuclear Schiff base palladacycle [Pd(C₆H₄CHNC₆H ₃-2,6-i-Pr₂)(imidazole)(SCN)]. Moreover, reactions of μ-azido and μ-thiocyanato bridged Schiff base palladacycles with triphenylphosphine and 1,4-bis(diphenylphosphino) butane routinely formed mono- and bi-nuclear terminal azido or isothiocyanato coordinated palladacycles [Pd{(4-R)C₆H₃CHN-C₆H₃-2,6-i-Pr ₂}(PPh₃)(N₃)], [Pd{(4-R)C₆H ₃CHN-C₆H₃-2,6-i-Pr₂}(PPh ₃)(NCS)], [Pd{(4-R)C₆H₃-CHN-C₆H ₃-2,6-i-Pr₂}(N₃)]₂(μ-dppb) and [Pd{(4-R)C₆H₃CHN-C₆H₃-2,6-i-Pr ₂}(NCS)]₂(μ-dppb) (R = H; OMe).

Full text of DOI:10.1016/j.jorganchem.2012.10.033

Journal of Organometallic Chemistry 724 (2013) 57e66
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Journal of Organometallic Chemistry
journal homepage: www.elsevier.com/locate/jorganchem
Reactivity of m-azido and m-thiocyanato bridged Schiff base palladacycles toward
aromatic N-heterocycles and phosphines
Yuchun Jiang a, Dandan Song a, Yu Wang a, Xiaowen Wan a, Yao Li a, Daliang Liu a, Ximing Song a,
,
,
*
Francis Verpoort b c, Xiaohong Chang a
a Liaoning Provincial Key Laboratory for Green Synthesis and Preparative Chemistry of Advanced Materials, College of Chemistry, Liaoning University, Shenyang 110036, PR China
b State Key Lab of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070, PR China
c Department of Inorganic and Physical Chemistry, Laboratory of Organometallic Chemistry and Catalysis, Ghent University, Krijgslaan 281 (S-3), 9000 Ghent, Belgium
a r t i c l e i n f o
a b s t r a c t
Article history:
Reaction of
(R ¼ H; OMe) with 1-methylimidazole generated different conformational mononuclear palladacycles.
Complexes [Pd{(4-R)C6H3CH]NeC6H3e2,6-i-Pr2}(
-N3)]2 (R ¼ H; OMe) reacted with bidentate 1,2-
bis(4-pyridyl)-ethene to give mononuclear palladacycles. Also the reaction of [Pd{C6H4CH]NeC6H3
e2,6-i-Pr2}(
-N3)]2 with 4,40-bipyridine (bpy) produced mononuclear palladacycles. However,
the reaction of [Pd{(4-MeO)C6H3CH]NeC6H3e2,6-i-Pr2}(
-N3)]2 with 4,40-bipyridine formed a 4,40-
bipyridine bridged binuclear palladacycle [Pd{(4-OMe)C6H3CH]NeC6H3e2,6-i-Pr2}(N3)]2( -bpy). In
contrast, -thiocyanato bridged Schiff base palladacycles were relatively unreactive toward aromatic
N-heterocycles. Only the reaction of [Pd{C6H4CH]NC6H3-2,6-i-Pr2}( -SCN)]2 with imidazole generated
thiocyanato coordinated mononuclear Schiff base palladacycle [Pd(C6H4CH]NC6H3-2,6-i-Pr2)(i-
midazole)(SCN)]. Moreover, reactions of -azido and -thiocyanato bridged Schiff base palladacycles
m-azido bridged Schiff base palladacycles [Pd{(4-R)C6H3CH]NeC6H3e2,6-i-Pr2}(m-N3)]2
Received 3 September 2012
Received in revised form
9 October 2012
m
Accepted 19 October 2012
m
m
Keywords:
m
Palladacycle
Schiff base
N-Heterocycle
Phosphine
m
m
a
m
m
with triphenylphosphine and 1,4-bis(diphenylphosphino) butane routinely formed mono- and bi-
nuclear terminal azido or isothiocyanato coordinated palladacycles [Pd{(4-R)C6H3CH]NeC6H3e2,6-i-
Pr2}(PPh3)(N3)], [Pd{(4-R)C6H3CH]NeC6H3e2,6-i-Pr2}(PPh3)(NCS)], [Pd{(4-R)C6H3eCH]NeC6H3e2,6-i-
Pr2}(N3)]2(
m
-dppb) and [Pd{(4-R)C6H3CH]NeC6H3e2,6-i-Pr2}(NCS)]2(
m
-dppb) (R ¼ H; OMe).
Ó 2012 Elsevier B.V. All rights reserved.
1. Introduction
bridged Schiff base palladacycles toward aromatic N-heterocycles
and phosphines. This study has allowed the preparation of a series
of novel azido, thiocyanato or isothiocyanato coordinated Schiff
base palladacycles.
In the last few decades, cyclometallation of C,N-chelating
ligands by palladium has remained as one of the major topics in
organometallic chemistry [1e8]. Recently, the reactivity of
m-chloro
and -acetato bridged Schiff base palladacycles toward phosphines
has been extensively studied due to their relevance to supramo-
m
2. Results and discussion
lecular chemistry [9e15]. We also reported mono-, bi- and tri-
2.1. Reactions of
palladacycles with aromatic N-heterocycles
m-azido and m-thiocyanato bridged Schiff base
nuclear Schiff-base palladacycles by reactions of
Schiff base palladacycles with aromatic N-heterocycles [16].
However, the reactivity of -azido and -thiocyanato bridged Schiff
m-chloro bridged
m
m
m
-Azido and
{(4-R)C6H3CH]NeC6H3e2,6-i-Pr2}(
[Pd{(4-R)C6H3CH]NeC6H3e2,6-i-Pr2}(
were synthesized by metathesis of the corresponding cyclo-
palladated chloro dimer [Pd{(4-R)C6H3CH]NeC6H3e2,6-i-Pr2}(
m
-thiocyanato bridged Schiff base palladacycles [Pd
-N3)]2 (R ¼ H, 1; OMe, 2) and
-SCN)]2 (R ¼ H, 3; OMe, 4)
base palladacycles is still unexplored, therefor, a novel reactivity
due to the azido and thiocyanato group could be introduced into
Schiff base palladacycles. Recently, we reported on the synthesis of
m
m
m
-azido and
m
-thiocyanato bridged Schiff base palladacycles [17].
-azido and -thiocyanato
m-
Herein, we describe the reactivity of
m
m
Cl)]2 with NaN3 and NH4SCN in CH2Cl2/CH3OH, respectively [17].
Subsequently, we examined the reactions of complexes 1e4 with
monodentate aromatic N-heterocycles, such as 1-methylimidazole
and imidazole, as shown Schemes 1 and 2. Treatment of complexes
1 and 2 with 2 equiv. 1-methylimidazole in CH2Cl2 at room
* Corresponding author. Tel.: þ86 24 62207823; fax: þ86 24 62202380.
E-mail addresses: cxh@lnu.edu.cn, c_x_hong@sina.com (X. Chang).
0022-328X/$ e see front matter Ó 2012 Elsevier B.V. All rights reserved.
http://dx.doi.org/10.1016/j.jorganchem.2012.10.033

58
Y. Jiang et al. / Journal of Organometallic Chemistry 724 (2013) 57e66
Scheme 1. Reactions of complexes 1 and 2 with monodentate aromatic N-heterocycles.
temperature produced yellow mononuclear Schiff base palla
dacycles [Pd{(4-R)C6H3CH]NC6H3-2,6-i-Pr2}(1-methylimidazole)
(N3)] (R ¼ H, 5; R ¼ OMe, 6). However, reaction of complexes 1 and
2 with 2 equiv. imidazole in CH2Cl2 at room temperature delivered
unknown oils, which were not further characterized. Complexes 5
and 6 were characterized by FT-IR, NMR, elemental analysis and
single crystal X-ray diffraction. A strong stretch vibration in the FT-
IR spectra of 5 and 6 was observed at approximately 2036 cmꢀ1
due to the terminal azido group, which was shifted to lower
wavenumbers compared to the bridging azido group present
toward 1-methylimidazole and imidazole comparing to complexes
1 and 2. Treatment of complexes 3 and 4 with 2 equiv. 1-
methylimidazoles in CH2Cl2 at room temperature did not produce
any mononuclear Schiff base palladacycles. Therefore, we synthe-
sized the chloro coordinated mononuclear Schiff base palladacycle
[Pd(C6H4CH]NeC6H3e2,6-i-Pr2)(1-methylimidazole)(Cl)] (7) by
reaction of the cyclopalladated chloro dimer [Pd(C6H4CH]Ne
C6H3e2,6-i-Pr2)(m-Cl)]2 with 1-methylimidazole. In an effort to
synthesize the thiocyanato or isothiocyanato coordinated mono-
nuclear Schiff base palladacycle by metathesis of 7 with NH4SCN in
CH2Cl2/CH3OH did not produce the expected product but a m-thi-
ocyanato bridged Schiff base palladacycle 3 was generated. This
result suggests that the coordinating ability of the thiocyanato
group to Pd is stronger compared to 1-methylimidazole. Unex-
pectedly, when complex 3 reacted with 2 equiv. imidazole in CH2Cl2
at room temperature, thiocyanato coordinated mononuclear Schiff
base palladacycle [Pd(C6H4CH]NC6H3-2,6-i-Pr2)(imidazole)(SCN)]
(8) was isolated. FT-IR spectra of 8 showed a characteristic stretch
vibration band at 2108 cmꢀ1 due to the S-coordinated thiocyanato
group [19], which was shifted to lower wavenumbers compared to
the bridged SCN group in complex 3 (2142 cmꢀ1). The molecular
in the starting materials (2062 cmꢀ1
)
[18] indicating that
1-methylimidazole cleaved cyclopalladated azido dimmers. The 1H
NMR spectra of 5 and 6 displayed the resonance for CH]N protons
at
compared to the corresponding N3-bridged cyclopalladated
complexes 1 and 2 ( 7.75 ppm and 7.61 ppm, respectively).
d 7.89 and d 7.75 ppm, respectively, indicating a downfield shift
d
d
Moreover, we recognized the presence of two isomers in solution of
5 and 6 according to the 1H NMR spectra (in the ratio of 1.00:0.16 for
5 and 1.00:0.15 for 6 based on the proton integration) and confir-
mation was obtained from the molecular structure of 5 and 6.
Interestingly, complexes 3 and 4 showed a distinctive reactivity
Scheme 2. Reactions of complexes 3 and 4 with monodentate aromatic N-heterocycles.

Y. Jiang et al. / Journal of Organometallic Chemistry 724 (2013) 57e66
59
structure of 3 also confirmed that the SCN group coordinates to Pd
through the S atom. The 1H NMR spectra of 8 displayed the reso-
Surprisingly, treatment of 2 with 1.0 equiv. 4,40-bipyridyl produced
the expected binuclear Schiff base palladacycle [Pd{(4-OMe)
nance for CH]N protons at
field compared to the corresponding SCN-bridged cyclopalladated
complex 3 ( 7.83 ppm). The resonance at 10.82 ppm in 3 was
assigned to NeH protons of coordinating imidazole ring.
In contrast, we are more interested in reactivity of -azido and
-thiocyanato bridged Schiff base palladacycles toward bi- and tri-
dentate aromatic N-heterocycles, expecting the formation of novel
bi- and tri-nuclear Schiff base palladacycles. Surprisingly, -azido
bridged Schiff base palladacycles showed complicated activities
(Schemes 3 and 4) and -thiocyanato bridged Schiff base pallada-
d
7.97 ppm, which was shifted down-
C6H3CH]NeC6H3e2,6-i-Pr2}(N3)]2(m-bpy) (11). Single crystal X-
ray analysis confirmed the binuclear structure of 11. However,
reaction of 2 with bpe is similar to the reaction of 1 with bpe though
only a mononuclear Schiff base palladacycle [Pd{(4-OMe)C6H3CH]
NC6H3-2,6-i-Pr2}(bpe)(N3)] (12) was obtained. The mononuclear
structure of 12 was also confirmed by single crystal X-ray analysis.
d
d
m
m
m
2.2. Reactions of
m-azido and m-thiocyanato bridged Schiff base
palladacycles with phosphines
m
cycles showed chemical stability with bi- and tri-dentate aromatic
N-heterocycles. When complex 1 reacted with 0.6 equiv. 4,40-
bipyridyl (bpy) in CH2Cl2 at room temperature, yellow mono-
nuclear Schiff base palladacycle [Pd(C6H4eCH]NC6H3e2,6-i-
Bearing in my mind the above results, as a comparative study,
we examined the reactions of complexes 1, 2, 3 and 4 with tertiary
and chelating phosphines, such as triphenylphosphine and 1,4-
bis(diphenylphosphino)butane (dppb) (Scheme 5). Although
Pr2)(bpy)(N3)] (9) was obtained. The formation of
9 was
several cleavage reactions of the
ladacycles by phosphines to give neutral or ionic complexes are
known [9e15], no example associated with -azido and -thio-
cyanato bridged Schiff base palladacycles is described in literature.
Recently, Kim et al. reported that -N3 bridged cyclometallated
m-chloro bridged Schiff base pal-
confirmed by FT-IR and 1H NMR spectra. FT-IR spectra of 9 showed
a strong stretch vibration band at 2044 cmꢀ1 assigned to terminal
N3 group instead of bridged N3 group at 2062 cmꢀ1. Elemental
analysis of 9 was consistent with the formula [C29H30N6Pd$CH2Cl2]
of the mononuclear structure. Single crystal X-ray analysis of 9 also
confirmed its mononuclear structure. However, treatment of 1 with
1.2e2.0 equiv. 4,40-bipyridyl did not yield the expected binuclear
Schiff base palladacycle, but produced 9 and 1. These results indi-
cated that the azido group and 4,40-bipyridyl competitively coor-
dinate to palladium during reaction. Similarly, when complex 1
reacted with 1.5 equiv. 1,2-bis(4-pyridyl)-ethene (bpe) in CH2Cl2 at
room temperature, mononuclear Schiff base palladacycle
[Pd(C6H4CH]NeC6H3e2,6-i-Pr2)(bpe)(N3)] (10) was obtained.
Treatment of 1 with 2.0 equiv. bpe produced 10 and initially 1.
Complex 10 was characterized by spectroscopic, elemental analysis.
Unfortunately, when complex 1 was treated by 2,5-bis(4-pyridyl)-
1,3,4-thiadiazole (bpt) or 2,4,6-tris-(4-pyridyl)-1,3,5-triazine (tpt),
no mono-, bi- or tri-nuclear Pd complexes were generated.
m
m
m
Pd(II) complexes containing C,N-chelating ligands, e.g. 2-(20-
thienyl)pyridine, azobenzene, 3,30-dimethyl azobenzene, N,N0-
dimethylbenzylamine, 2-phenylpyridine exhibited a labile reac-
tivity toward chelating phosphines [20]. In our study, consistent
with the expectation based on stoichiometry, the mononuclear and
binuclear Schiff base palladacycles with a terminal N3 group or NCS
group [Pd{(4-R)C6H3CH]NeC6H3e2,6-i-Pr2}(PPh3)(N3)] (R ¼ H,
13; OMe, 14), [Pd{(4-R)C6H3CH]NeC6H3e2,6-i-Pr2}(PPh3)(NCS)]
(R ¼ H, 15; OMe, 16), [Pd{(4-R)C6H3CH]NeC6H3e2,6-i-Pr2}(N3)]2
(
m
-dppb) (R ¼ H, 17; OMe, 18) and [Pd{(4-R)C6H3CH]NeC6H3e2,6-
i-Pr2}(NCS)]2(
m
-dppb) (R ¼ H, 19; OMe, 20) were formed when
complexes 1e4 were treated with the stoichiometric amount of
PPh3 or dppb, respectively. Complexes 13e20 were characterized
by spectroscopic and elemental analysis. The molecular structures
Scheme 3. Reactions of complex 1 with bidentate aromatic N-heterocycles.

60
Y. Jiang et al. / Journal of Organometallic Chemistry 724 (2013) 57e66
Scheme 4. Reactions of complex 2 with bpy and bpe.
of 14,15,17 and 20 were determined using X-ray diffraction. The FT-
IR spectra of 13 and 14 showed a characteristic stretch vibration
band at approximately 2044 cmꢀ1 and 2037 cmꢀ1, respectively, due
to the terminal azido group, similar to 5 and 6. Nonetheless,
a difference between 5, 6 and 13, 14 can be found in the absence of
linkage isomers in solution based on 1H NMR. For 17 and 18, strong
stretching vibration of terminal N3 also appear at 2038 cmꢀ1 and
2037 cmꢀ1, respectively. The presence of strong absorptions at
2091 cmꢀ1 (15), 2089 cmꢀ1 (16), 2084 cmꢀ1 (19) and 2086 cmꢀ1
(20) can be assigned to the coordinated isothiocyanato group,
which is shifted to lower wavenumbers compared to the coordi-
nated thiocyanato group of 8. 1H NMR spectra of 13e20 are
consistent with their structure in solution. Therefor, the resonance
of CH]N in 13e20 splits into doublets due to the coupling between
H and P.
collection, and refinement are given in Table 1, and data of 8, 9, 12,
15 and 20 are in Table S1 (Supplementary Data). In all structures,
the coordination of the Pd metal is essentially square-planar.
As shown in Fig. 1, 5 contain a cyclometallated Schiff-base
ligand, a 1-methylimidazole and an azido group. The azido group
is located on the trans-position of PdeC bond and the 1-
methylimidazole is located on the trans-position of PdeN bond.
The five-membered chelate ring that contains the imine function-
ality defined by Pd1, N1, C13, C14 and C15 is essentially planar with
ꢀ
the atomic displacements not exceeding 0.0619 A, to which the
diisopropylphenyl ring is almost perpendicular with a dihedral
angle 87.7(6)ꢁ. The dihedral angle between the cyclometallated ring
ꢁ
ꢀ
and the imidazole ring is 51.5 . The Pd1eC15 bond [1.989(2) A] and
ꢀ
Pd1eN1 [2.0372(17) A] are almost equal to corresponding N3-
3
ꢀ
ꢀ
bridged cyclopalladated complex 1 [1.983(6) A] and [2.037(5) A] .
Fig. 2 reveals the cis disposition of the azido group relative to
the metalated carbon atom and the cis disposition of the
1-methylimidazole relative to the metalated imine nitrogen atom
in compound 6. This arrangement is unusual in cyclopalladated
compounds. The Pd1eC15 bond [1.988(3) A] of compound 6 is
almost equal to that of 5, but the Pd1eN1bond [2.062(3) A] is
longer compared to 5. Pd1eN2 bond [2.0343(17) A] located on the
2.3. Structures of compounds
Single crystals of 5, 6, 8, 9, 12, 14, 15, 17 and 20 suitable for X-ray
diffraction analysis were obtained from a dichloromethane/hexane
solution while single crystals of 11 from a chloroform/hexane
solution. Details of 5, 6, 11, 14 and 17 on crystal data, intensity
ꢀ
ꢀ
ꢀ
Scheme 5. Reactions of complexes 1e4 with phosphines.

Y. Jiang et al. / Journal of Organometallic Chemistry 724 (2013) 57e66
61
Table 1
X-ray data collection and structure refinement for 5, 6, 11, 14, 17.
5
6$CH2Cl2
11$2CHCl3
14$CH2Cl2
17
Formula
C
23H28N6Pd
C25H32Cl2N6OPd
609.87
296(2)
0.9 ꢂ 0.25 ꢂ 0.21
Triclinic
P1
8.2046(4)
11.1509(6)
16.4366(9)
98.9790(10)
90.1880(10)
110.9250(10)
1384.53(13)
2
C52H58Cl6N10O2Pd2
1280.64
296(2)
0.33 ꢂ 0.28 ꢂ 0.21
Triclinic
P1
10.812(2)
11.100(2)
18.401(4)
84.33(3)
87.96(3)
61.56(3)
1932.2(7)
2
C39H41Cl2N4OPPd
790.03
296(2)
0.33 ꢂ 0.27 ꢂ 0.22
Monoclinic
Pca21/c
9.7026(16)
21.120(3)
19.723(3)
90.00
105.207(7)
90.00
3900.1(10)
4
1.345
0.688
C66H72N8P2Pd2
1252.06
296(2)
0.30 ꢂ 0.26 ꢂ 0.21
Monoclinic
P21/c
9.3508(7)
15.1746(11)
22.2092(17)
90.00
90.5810(10)
90.00
3151.2(4)
2
1.320
0.666
Formula weight
Temperature (K)
Crystal size
494.91
293(2)
0.30 ꢂ 0.26 ꢂ 0.21
Monoclinic
P21/c
10.088(2)
14.598(3)
17.696(5)
90.00
117.79(2)
90.00
2305.4(9)
4
Crystal system
Space group
ꢀ
a, A
ꢀ
b, A
ꢀ
c, A
a, deg
b
, deg
g
, deg
3
ꢀ
V, A
Z
dcal, g cmꢀ3
1.426
0.826
1.463
0.892
1.474
1.071
m
, mmꢀ1
F(000)
1016
624
872
1624
1292
Tmin
Tmax
0.790
0.855
17,707
4142
0.784
0.840
19,567
4936
0.7394
0.8261
15,443
6916
0.811
0.872
27,722
6990
0.8251
0.8727
23,427
5631
No. of reflns measured
No. of reflns unique
No. of params refined
276
0.564
322
0.702
436
1.522
438
0.698
357
0.527
ꢀꢀ3
Max., in Dr (eA
Min., in Dr (eAꢀ3)
)
ꢀ
ꢀ0.291
ꢀ0.507
ꢀ1.453
ꢀ0.930
ꢀ0.381
GOF on F2
1.144
1.169
1.193
1.009
1.099
R (I > 2
wR2 (I > 2
s
(I))
s
0.0266
0.0736
0.0291
0.0752
0.0309
0.0948
0.0366
0.1217
0.0576
0.1491
0.1086
0.2366
0.0724
0.1953
0.1489
0.2610
0.0392
0.0980
0.0681
0.1296
a
(I))
R (all data)
a
wR2 (all data)
a
wR2 ¼ S[w(F2o ꢀ F2c)2]/S[w(F2o)2]1/2
.
cis-position of Pd1eC15 bond in 6 is significantly shorter than Pd1e
the imine functionality defined by Pd1, N1, C13, C14 and C15 is
ꢀ
N4 bond [2.137(2) A] located on the trans-position of Pd1eC15
essentially planar with the atomic displacements not exceeding
ꢀ
ꢀ
bond in 5, and Pd1eN5 bond [2.156(3) A] located on the trans-
0.0264 A. The dihedral angle between the diisopropylphenyl ring
position of Pd1eC15 bond in 6 is considerably longer than Pd1eN2
bond [2.0343(17) A] located on the cis-position of Pd1eC15 bond in
and the five-membered chelate ring turns into 72.05ꢁ due to the
effect of the coordinated imidazole ring. The dihedral angle
between the cyclometallated ring and the imidazole ring is 34.59ꢁ.
As depicted in Fig. S1 (in Supplementary Data), the palladium atom
of complex 8 coordinated with a cyclometallated Schiff-base ligand,
ꢀ
5. This can be ascribed to a higher trans influence of the carbon. For
ꢀ
compound 6 N2 is 0.1782 A out of the molecule planar, defined by
N1, Pd1, C15 and N5. The five-membered chelate ring that contains
ꢁ
ꢀ
Fig. 1. Molecular structure of 5. Selected bond lengths (A) and angles ( ): Pd1eC15 1.989(2), Pd1eN1 2.0372(17), Pd1eN2 2.0343(17), Pd1eN4 2.137(2), N4eN5 1.158(3), N5eN6
1.165(4); N1ePd1eC15 81.21(8), N2ePd1eC15 94.86(8), N2ePd1eN1 174.49(6), N2ePd1eN4 89.03(9), N5eN4ePd1 128.7(2), N4eN5eN6 176.4(3).

62
Y. Jiang et al. / Journal of Organometallic Chemistry 724 (2013) 57e66
ꢁ
ꢀ
Fig. 2. Molecular structure of 6. Selected bond lengths (A) and angles ( ): Pd1eC15 1.988(3), Pd1eN1 2.062(3), Pd1eN2 2.038(3), Pd1eN5 2.156(3), N2eN3 1.169(5), N3eN4
1.167(5); N1ePd1eC15 80.67(12), N1ePd1eN2 170.78(12), N5ePd1eC15 178.79(12), N5ePd1eN1 98.98(11), N3eN2ePd1 120.0(3), C15ePd1eN2 91.62(14), N4eN3eN2 176.0(4).
an imidazole and a thiocyanato group. Sulfur and metalated carbon
atoms adopt a trans arrangement.
0.0006, 0.0207, ꢀ0.0492, 0.0600 and ꢀ0.0399 for Pd1, N1, C15, N2
and N5, respectively. The five-membered chelate ring that contains
the imine functionality is almost perpendicular to the diisopro-
pylphenyl ring with a dihedral angle 84.5(1)ꢁ. The two pyridyl rings
of the bpy liganꢁd are not coplanar but twisted to each other by an
Complexes 9 (Fig. 3) and 12 (Fig. S2 in Supplementary Data)
have a similar mononuclear structure. Likewise, it is similar to
complex 6 where the azido group is in cis position relative to
metalated carbon atom. For 9, the coordination plane shows a slight
tetrahedral distortion, the deviation from the mean plane being
ꢀ
angle of 26.3(2) . For 12, N4 is 0.2150 A out of the molecule planar,
defined by N1, Pd1, C27 and N3. The dihedral angle between the
ꢁ
ꢀ
Fig. 3. Molecular structure of 9. Selected bond lengths (A) and angles ( ): Pd1eC 151.990(4), Pd1eN1 2.051(5), Pd1eN2 2.013(6), Pd1eN5 2.160(3), N2eN3 1.205(9), N3eN4
1.133(9); C15ePd1eN1 80.7(2), C15ePd1eN5 177.3(2), C15ePd1eN2 95.6(3), N1ePd1eN5 98.5(2), N2ePd1eN1 175.56(19), N3eN2ePd1 123.2(5), N4eN3eN2 174.7(7).

Y. Jiang et al. / Journal of Organometallic Chemistry 724 (2013) 57e66
63
diisopropylphenyl ring and the five-membered chelate ring turns
NeC6H3e2,6-i-Pr2) (imidazole)(SCN)] was produced. Moreover,
reactions of -azido and -thiocyanato bridged Schiff base palla-
into 69.8ꢁ due to the effect of coordinated bpe. Fig. 4 reveals that
m
m
complex 11 has a dimeric structure bridged by
m
-bpy. Each Pd
dacycles with triphenylphosphine and 1,4-bis(diphenylphosphino)
butane regularly formed mono- and bi-nuclear terminal azido or
isothiocyanato coordinated palladacycles.
center contains a cyclometallated Schiff-base ligand, a bridging bpy
ligand and a terminal azido ligand. 4,40-Bipyridyl links two [Pd{(4-
MeO)C6H3CH]NeC6H3e2,6-i-Pr2}(N3)] moieties to give a binu-
ꢀ
clear compound, and the distance of Pd(1)/Pd(1A) is 11.4539(8) A.
3. Experimental
The two cyclometallated ligands are in a trans arrangement with
respect to the Pd/Pd axis. The molecule planar, defined by Pd1, N2,
C15, N1 and N3 (plane 1), is relatively planar with the atomic
displacements not exceeding 0.0214 A. Two pyridyl rings of
bridging bpy ligand are essentially coplanar.
3.1. General, materials and measurements
ꢀ
All manipulations of air-sensitive compounds were performed
under nitrogen applying standard Schlenk techniques. All solvents
were purified and degassed before use; other reagents were used as
supplied. 1H NMR spectra were obtained in CDCl3 with TMS as an
internal standard using a Mercury-300 spectrometer. IR spectra
were recorded on a Nicolet AVATAR 330 FT-IR spectrometer.
Elemental analyses were performed using a Thermo Flash EA1112
Analyzer.
Fig. 5 shows that complex 14 contains a C,N-coordinating Schiff-
base ligand, one PPh3, and one terminal azido ligand. The difference
with complexes 9 and 12 can be found in the trans position of the
azido group instead of cis relative to the metalated carbon atom.
ꢀ
The Pd2eC15 bond [2.026(8) A] of compound 14 is longer than
ꢀ
those of 9 and 12. Pd2eN2 bond [2.091(8) A] located on the trans-
position of Pd2eC15 bond in 14 is significantly longer than Pd1eN2
bond [2.013(6) A] located on the cis-position of Pd1eC15 bond in 9.
Caution! No problems were encountered during this work,
however heavy metal azides are known to be shock sensitive
detonators, therefore it is essential to handle any palladium azide
compound carefully.
ꢀ
Complex 15 (Fig. S3 in Supplementary Data) reveals similarly
structure with 14 containing a C,N-coordinating Schiff-base ligand,
one PPh3, and one terminal isothiocyanato group. The iso-
thiocyanato group is in trans position relative to the metalated
carbon atom. Also complexes 17 and 20 have a similar dinuclear
structure. In complex 17 (Fig. 6) dppb links two [Pd{(4-MeO)
C6H3CH]NeC6H3e2,6-i-Pr2}(N3)] moieties to give a binuclear
compound containing a terminal azido group, and the distance of
3.2. Preparations
3.2.1. [Pd(C6H4CH]NeC6H3e2,6-i-Pr2)(1-methylimidazole)(N3)]
(5), [Pd{(4-MeO)C6H3eCH]NeC6H3e2,6-i-Pr2}(1-methylimidazole)
(N3)] (6)
ꢀ
Pd(1)/Pd(1A) is 8.7349(7) A. In complex 20 (Fig. S4 in Supple-
To a 12 mL CH2Cl2 solution of complex [Pd(C6H4CH]NeC6H3e
mentary Data) dppb links two [Pd{(4-MeO)C6H3CH]NeC6H3e2,6-
i-Pr2)}(NCS)] moieties to give a binuclear compound containing
2,6-i-Pr2)(
methylimidazole (20
m
-N3)]2 (1) (0.100 g, 0.12 mmol) was added stepwise 1-
mL, 0.25 mmol). After stirring for 12 h at
a terminal isothiocyanato group, and the distance of Pd(1)/Pd(1A)
room temperature, the solvent was completely evaporated and the
resulting residue was washed with ether to give a pale yellow
solid. Recrystallization from CH2Cl2/hexane gave yellow crystals
of [Pd(C6H4CH]NeC6H3e2,6-i-Pr2)(1-methylimidazole)(N3)] (5,
ꢀ
is 9.0591(8) A. Two cyclometallated ligands are in
a trans
arrangement with respect to the Pd/Pd axis.
In summary, the reactivity of
Schiff base palladacycles toward aromatic N-heterocycles and
phosphines was examined. Due to the lability of -azido bridged
m-azido and m-thiocyanato bridged
0.071 g, 59%). IR (KBr, cmꢀ1): 1601 (
NMR (300 MHz in CDCl3,
n
C]N), 2036 (
n
N]N]N); 1H
m
d
): 7.89 (s, 1H, eCH]N), 7.80 (d, 1H,
Schiff base palladacycles toward aromatic N-heterocycles mono-
and bi-nuclear compounds were generated. Unexpectedly, only one
J ¼ 7.8 Hz), 7.41 (d, 1H, J ¼ 7.5 Hz), 7.34 (t, 1H, J ¼ 6.9 Hz, 8.1 Hz),
7.24e7.29 (m, 1H), 7.16e7.21 (m, 1H), 7.12 (d, 2H, J ¼ 7.8 Hz), 6.83 (s,
1H), 6.55 (s, 1H), 6.13 (s, 1H), 3.47 (s, 1H, NeCH3), 3.38 (hepta, 2H, e
CH(CH3)2), 1.12 (d, 6H, J ¼ 6.6 Hz, eCH(CH3)2), 1.05 (d, 6H, J ¼ 6.9 Hz,
eCH(CH3)2); Anal. Calcd for C23H28N6Pd: C, 55.82; H, 5.70; N, 16.98.
Found: C, 55.64; H, 5.67; N, 16.61.
binuclear palladacycle was synthesized by reaction of
m-azido Schiff
base palladacycles with bidentate N-heterocycles. Furthermore,
m-
thiocyanato bridged Schiff base palladacycles were relatively
unreactive toward aromatic N-heterocycles. Only one thiocyanato
coordinated mononuclear Schiff base palladacycle [Pd(C6H4CH]
Complexes 6e20 were prepared in a similar manneras complex 5.
ꢁ
ꢀ
Fig. 4. Molecular structure of 11. Selected bond lengths (A) and angles ( ): Pd1eC15 1.989(5), Pd1eN1 2.168(4), Pd1eN2 2.055(4), Pd1eN3 2.043(5), N3eN4 1.159(7), N4eN51
153(8); C15ePd1eN2 80.30(19), C15ePd1eN1 176.82(18), C15ePd1eN3 91.6(2), N3ePd1eN2 171.87(18), N2ePd1eN1 96.57(17), N4eN3ePd1 123.3(4), N5eN4eN3 176.3(7).

64
Y. Jiang et al. / Journal of Organometallic Chemistry 724 (2013) 57e66
ꢁ
ꢀ
Fig. 5. Molecular structure of 14. Selected bond lengths (A) and angles ( ): Pd2eC15 2.026(8), Pd2eN1 2.094(7), Pd2eN2 2.091(8), Pd2eP1 2.245(2), N2eN3 1.211(15), N3eN4
1.163(16); C15ePd2eN1 80.4(3), C15ePd2eN2 170.7(3), C15ePd2eP1 94.0(2), N1ePd2eP1 172.7(2), N2ePd2eN1 91.8(3), C27eP1ePd2 108.9(3), C21eP1ePd2 114.3(4), C33eP1e
Pd2 116.9(3), N3eN2ePd2 122.3(8), N4eN3eN2 176.3(14), C1eN1ePd2 124.5(5).
ꢁ
ꢀ
Fig. 6. Molecular structure of 17. Selected bond lengths (A) and angles ( ): Pd1eC15 2.028(4), Pd1eN1 2.093(4), Pd1eN2 2.122(4), Pd1eP1 2.2548(11), N2eN3 1.136(6), N3eN4
1.178(7); C15ePd1eN1 80.71(16), C15ePd1eN2 166.58(17), C15ePd1eP1 95.52(13), N2ePd1eP1 92.21(12), N1ePd1eP1 170.21(10), N3eN2ePd1 132.4(4), N2eN3eN4 175.6(8),
C20eP1ePd1 116.88(14), C26eP1ePd1 114.72(16), C32eP1ePd1 112.22(15), C1eN1ePd1 124.7(3).

Y. Jiang et al. / Journal of Organometallic Chemistry 724 (2013) 57e66
65
3.2.2. [Pd{(4-MeO)C6H3CH]NeC6H3e2,6-i-Pr2}(1-methylimida
zole(N3)] (6, 51%)
J ¼ 7.5, 7.8 Hz, H5), 6.46 (dd, 1H, J ¼ 5.4 Hz, 5.4 Hz, H3), 3.41 (hepta,
2H, eCH(CH3)2), 1.41 (d, 6H, J ¼ 6.6 Hz, eCH(CH3)2), 1.22 (d, 6H,
J ¼ 6.9 Hz, eCH(CH3)2). Anal. Calcd for C37H37N4PPd$0.125CH2Cl2: C,
65.03; H, 5.48; N, 8.17. Found: C, 64.96; H, 5.78; N, 7.90.
IR (KBr, cmꢀ1): 1598
(
n
C]N), 2036
(n
N]N]N); 1H NMR
(300 MHz in CDCl3,
d
): 7.75 (s, 1H, eCH]N), 7.36 (d, 1H, J ¼ 2.4 Hz,
imidazole), 7.32 (d, 1H, J ¼ 8.4 Hz), 7.23 (d, 1H, J ¼ 7.8 Hz), 7.09 (d,
2H, J ¼ 7.5 Hz), 6.82 (s, 1H), 6.67 (dd, 1H, J ¼ 2.4, 2.4 Hz, imidazole),
6.54 (s, 1H), 6.15 (s, 1H), 3.97 (s, 3H, eOCH3), 3.47 (s, 3H, NeCH3),
3.39 (hepta, 2H, eCH(CH3)2), 1.10 (d, 6H, J ¼ 6.9 Hz, eCH(CH3)2),
1.04 (d, 6H, J ¼ 6.9 Hz, eCH(CH3)2); Anal. Calcd for C24H30N6OPd: C,
54.91; H, 5.76; N, 16.01. Found: C, 54.79; H, 5.96; N, 16.35.
3.2.9. [Pd{(4-MeO)C6H3CH]NeC6H3e2,6-i-Pr2}(PPh3)(N3)] (14, 92%)
IR (KBr, cmꢀ1): 1606 (
n
C]N), 2037(
n
N]N]N); 1H NMR (300 MHz
in CDCl3,
d
): 7.96 (d, 1H, J ¼ 8.1 Hz, eCH]N), 7.67e7.75 (m, 6H,
6
3
4
5
0
0
0
PPh3), 7.32e7.49 (m, 10H, PPh3, H ), 7.16e7.26 (m, 3H, H , H , H ),
6.51 (dd, 1H, J ¼ 2.4 Hz, 2.4 Hz, H5), 6.05 (dd, 1H, J ¼ 2.1 Hz, 2.4 Hz,
H3), 3.42 (hepta, 2H, eCH(CH3)2), 3.08 (s, 3H, eOCH3), 1.40 (d, 6H,
J ¼ 6.6 Hz, eCH(CH3)2), 1.20 (d, 6H, J ¼ 6.9 Hz, eCH(CH3)2). Anal.
Calcd for C38H39N4OPPd$0.125CH2Cl2: C, 63.98; H, 5.53; N, 7.83.
Found: C, 64.17; H, 5.91; N, 7.85.
3.2.3. [Pd(C6H4CH]NeC6H3e2,6-i-Pr2)(imidazole)(SCN)] (8, 59%)
IR (KBr, cmꢀ1): 1603 (
n
C]N), 2108(
n
S]C]N); 1H NMR (300 MHz
in CDCl3,
d): 10.82 (s, 1H, NeH), 7.97 (s, 1H, eCH]N), 7.37e7.44 (m,
2H), 7.23 (d, 1H, J ¼ 7.5 Hz), 7.19 (d, 1H, J ¼ 6.9 Hz), 7.09e7.15 (m,
3H),6.98 (d, 2H, J ¼ 7.5 Hz), 6.51 (s, 1H), 3.32 (hepta, 2H, e
CH(CH3)2), 1.15 (d, 6H, J ¼ 6.6 Hz, eCH(CH3)2), 1.08 (d, 6H, J ¼ 6.9 Hz,
eCH(CH3)2); Anal. Calcd for C23H26N4PdS: C, 55.59; H, 5.27; N,11.27.
Found: C, 55.56; H, 5.28; N, 11.05.
3.2.10. [Pd(C6H4CH]NeC6H3e2,6-i-Pr2)(PPh3)(NCS)] (15, 80%)
IR (KBr, cmꢀ1): 1610 (
n
C]N), 2091 (
n
N]C]S); 1H NMR (300 MHz
in CDCl3,
d
): 8.07 (d, 1H, J ¼ 7.8 Hz), 7.66 (dd, 6H, J ¼ 7.2, 7.2 Hz,
6
3
4
5
0
0
0
PPh3), 7.39e7.51 (m, 10H, PPh3, H ), 7.22e7.33 (m, 3H, H , H , H ),
7.02 (dd, 1H, J ¼ 7.5, 7.2 Hz, H4), 6.69 (dd, 1H, J ¼ 7.5, 7.8 Hz, H5), 6.46
(dd, H, J ¼ 6.0 Hz, 7.2 Hz, H3), 3.41 (hepta, 2H, eCH(CH3)2), 1.41 (d,
6H, J ¼ 6.9 Hz, eCH(CH3)2), 1.23 (d, 6H, J ¼ 6.6 Hz, eCH(CH3)2). Anal.
Calcd for C38H37N2PPdS: C, 66.03; H, 5.40; N, 4.05; S, 4.64. Found: C,
65.91; H, 5.53; N, 3.90; S, 4.40.
3.2.4. [Pd(C6H4CH]NeC6H3e2,6-i-Pr2)(bpy)(N3)] (9, 57%)
IR (KBr, cmꢀ1): 1602 ( N]N]N); 1H NMR (300 MHz
nC]N), 2044(n
in CDCl3,
d
): 8.74 (d, 2H, J ¼ 5.1 Hz), 8.21 (d, 2H, J ¼ 6.0 Hz), 7.94 (s,
1H, eHC]N), 7.40 (d, 2H, J ¼ 5.7 Hz), 7.37 (d, 2H, J ¼ 7.8 Hz), 7.31 (d,
2H, J ¼ 6.3 Hz), 7.22 (d, 2H, J ¼ 7.8 Hz), 7.13e7.18 (m, 2H), 7.02 (d, 2H,
J ¼ 7.2 Hz), 3.42 (hepta, 2H, eCH(CH3)2),1.11 (dd, 12H, J ¼ 3.0 Hz, e
CH(CH3)2); Anal. Calcd for C29H30N6Pd$0.125CH2Cl2: C, 60.35; H,
5.26; N, 14.50. Found: C, 60.30; H, 5.19; N, 14.18.
3.2.11. [Pd{(4-MeO)C6H3CH]NeC6H3e2,6-i-Pr2}(PPh3)(NCS)]
(16, 54%)
IR (KBr, cmꢀ1): 1606 (
n
C]N), 2089 (
n
N]C]S); 1H NMR (300 MHz
in CDCl3,
d
): 7.95 (d, 1H, J ¼ 7.8 Hz), 7.67 (dd, 6H, J ¼ 7.2 Hz, 7.2 Hz,
3.2.5. [Pd(C6H4CH]NeC6H3e2,6-i-Pr2)(bpe)(N3)] (10, 49%)
PPh3), 7.40e7.52 (m, 9H, PPh3), 7.35 (d,1H, J ¼ 8.4 Hz), 7.21e7.32 (m,
3H), 6.53 (dd, 1H, J ¼ 2.1, 2.1 Hz), 6.03 (d, 1H, J ¼ 3.9 Hz), 3.42 (hepta,
2H, eCH(CH3)2), 3.07 (s, 3H, eOCH3), 1.47 (d, 6H, J ¼ 6.6 Hz, e
CH(CH3)2), 1.23 (d, 6H, J ¼ 6.6 Hz, eCH(CH3)2). Anal. Calcd for
C39H39N2OPPdS$0.25CH2Cl2: C, 63.50; H, 5.36; N, 3.77; S, 4.32.
Found: C, 63.80; H, 5.34; N, 3.47; S, 4.05.
IR (KBr, cmꢀ1): 1599
(nC]N), 2023 (n
N]N]N); 1H NMR
(300 MHz in CDCl3,
d
): 8.63 (d, 2H, J ¼ 5.1 Hz), 8.07 (d, 2H,
J ¼ 5.4 Hz), 7.93 (s, 1H, eHC]N), 7.39e7.44 (m, 3H), 7.35 (d, 2H,
J ¼ 5.7 Hz), 7.21 (d, 1H, J ¼ 6.6 Hz), 7.12e7.16 (m, 3H), 7.09 (d, 1H,
J ¼ 8.4 Hz), 7.02 (d, 2H, J ¼ 7.5 Hz), 3.42 (hepta, 2H, eCH(CH3)2),1.11
(d, 12H,
J
¼
6.3 Hz, eCH(CH3)2). Anal. Calcd for
C31H32N10Pd$0.5CH2Cl2: C, 59.35; H, 5.22; N, 13.18. Found: C, 59.45;
3.2.12. [Pd(C6H4CH]NeC6H3e2,6-i-Pr2)(N3)]2(
IR (KBr, cmꢀ1): 1611 ( N]N]N); 1H NMR (300 MHz
C]N), 2038 (
in CDCl3,
): 8.01 (d, 2H, J ¼ 6.9 Hz, eCH]N), 7.73e7.79 (m, 8H, Pe
m-dppb) (17, 61%)
H, 5.25; N, 13.13.
n
n
d
6
3
4
5
0
0
0
3.2.6. [Pd{(4-MeO)C6H3CH]NeC6H3e2,6-i-Pr2}(N3)]2(
(11, 54%)
m
-bpy)
Ph), 7.30e7.44 (m, 14H, PePh, H ), 7.22e7.28 (m, 6H, H , H , H ),
6.96 (dd, 2H, J ¼ 7.2, 7.5 Hz, H4), 6.69 (dd, 2H, J ¼ 7.5, 6.9 Hz, H5),
6.48 (dd, 2H, J ¼ 4.5, 4.5 Hz, H3), 3.36 (hepta, 4H, eCH(CH3)2), 2.34
(br, 4H, PeCH2eCH2e), 1.61 (br, 4H, PeCH2eCH2e), 1.37 (d, 12H,
J ¼ 6.6 Hz, eCH(CH3)2), 1.19 (d, 12H, J ¼ 6.9 Hz, eCH(CH3)2). Anal.
Calcd for C66H72N8P2Pd2: C, 63.31; H, 5.80; N, 8.95. Found: C, 63.06;
H, 6.21; N, 8.88.
IR (KBr, cmꢀ1): 1597 ( N]N]N); 1H NMR (300 MHz
nC]N), 2035(n
in CDCl3,
d
): 8.70 (d, 4H, J ¼ 5.7 Hz), 8.17 (d, 4H, J ¼ 5.1 Hz), 7.77 (s,
2H, eHC]N), 7.37 (d, 2H, J ¼ 7.8 Hz), 7.18 (d, 4H, J ¼ 7.5 Hz), 7.13 (d,
2H, J ¼ 7.5 Hz), 6.94 (d, 2H, J ¼ 7.8 Hz), 6.73 (d, 2H, J ¼ 8.1 Hz), 3.96(s,
6H, eOCH3), 3.39 (hepta, 4H, eCH(CH3)2), 1.07 (dd, 24H, J ¼ 2.7 Hz,
3.0 Hz, eCH(CH3)2). Anal. Calcd for C50H56N10O2Pd2: C, 57.64; H,
5.42; N, 13.44. Found: C, 57.36; H, 5.70; N, 13.32.
3.2.13. [Pd{(4-MeO)C6H3CH]NeC6H3e2,6-i-Pr2}(N3)]2(
m-dppb)
(18, 54%)
3.2.7. [Pd{(4-MeO)C6H3CH]NeC6H3e2,6-i-Pr2}(bpe)(N3)] (12, 74%)
IR (KBr, cmꢀ1): 1606 (
n
C]N), 2037(
n
N]N]N); 1H NMR (300 MHz
IR (KBr, cmꢀ1): 1609 (
n
C]N), 2037(
n
N]N]N); 1H NMR (300 MHz
in CDCl3, d
): 7.89 (d, 2H, J ¼ 7.8 Hz, eCH]N), 7.77 (dd, 8H, PePh),
6
4
0
in CDCl3,
d
): 8.63 (d, 1H, J ¼ 5.7 Hz), 8.07 (d, 2H, J ¼ 6.3 Hz), 7.79 (s,
7.32e7.46 (m, 12H, PePh), 7.28 (d, 4H, J ¼ 8.4 Hz, H , H ), 7.21 (d,
3 5 5
0
0
1H, eHC]N), 7.33e7.36 (m, 3H), 7.29 (d, 1H, J ¼ 8.4 Hz), 7.21 (d, 1H,
J ¼ 8.4 Hz), 7.17 (d, 1H, J ¼ 3.9 Hz), 7.13 (d, 2H, J ¼ 7.2 Hz), 7.08 (d, 1H,
J ¼ 7.5 Hz), 7.01 (d, 1H, J ¼ 2.7 Hz), 6.99 (d, 1H, J ¼ 3.0 Hz), 6.95 (d,
1H, J ¼ 6.9 Hz), 6.71 (dd, 1H, J ¼ 2.4 Hz), 3.98 (s, 3H, OCH3), 3.42
(hepta, 2H, eCH(CH3)2),1.09 (dd, 12H, J ¼ 6.3 Hz, 5.4 Hz, e
CH(CH3)2). Anal. Calcd for C32H34N6OPd$0.5CH2Cl2: C, 58.48; H,
5.28; N, 12.59. Found: C, 58.27; H, 5.19; N, 12.22.
4H, J ¼ 7.5 Hz, H , H ), 6.48 (d, 2H, J ¼ 8.4 Hz, H ), 6.04 (d, 2H,
J ¼ 4.2 Hz, H3), 3.38 (hepta, 4H, eCH(CH3)2), 3.06 (s, 6H, OCH3), 2.37
(br, 4H, PeCH2eCH2e), 1.70 (br, 4H, PeCH2eCH2e), 1.36 (d, 12H,
J ¼ 6.9 Hz, eCH(CH3)2), 1.19 (d, 12H, J ¼ 6.9 Hz, eCH(CH3)2). Anal.
Calcd for C68H76N8O2P2Pd2: C, 62.24; H, 5.84; N, 8.54. Found: C,
62.24; H, 5.79; N, 8.63.
3.2.14. [Pd(C6H4CH]NeC6H3e2,6-i-Pr2)(NCS)]2(
IR (KBr, cmꢀ1): 1616 ( N]C]S); 1H NMR (300 MHz
C]N), 2084(
in CDCl3,
Ph), 7.34e7.44 (m, 14H, PePh, H ), 7.26e7.31 (m, 6H, H , H , H ),
6.96 (dd, 2H, J ¼ 7.2, 7.5 Hz, H4), 6.66 (dd, 2H, J ¼ 7.5, 7.5 Hz, H5), 6.45
(dd, 2H, J ¼ 5.7, 7.5 Hz, H3), 3.35 (hepta, 4H, eCH(CH3)2), 2.36 (br,
m-dppb) (19, 59%)
3.2.8. [Pd(C6H4CH]NeC6H3e2,6-i-Pr2)(PPh3)(N3)] (13, 70%)
n
n
IR (KBr, cmꢀ1): 1612 (
n
C]N) 2044 (
n
N]N]N); 1H NMR (300 MHz
d
): 7.99 (d, 2H, J ¼ 7.5 Hz, eCH]N), 7.82e7.88 (m, 8H, Pe
6 3 4 5
0
0
0
in CDCl3,
d
): 8.08 (d, 1H, J ¼ 7.8 Hz, eCH]N), 7.68e7.75 (m, 6H,
6
3
5
0
0
PPh3), 7.34e7.49 (m, 10H, PPh3, H ), 7.23 (d, 2H, J ¼ 6.9 Hz, H , H ),
4
0
4
7.12e7.19 (m, 1H, H ), 7.01 (dd, 1H, J ¼ 7.5, 7.2 Hz, H ), 6.69 (dd, 1H,

66
Y. Jiang et al. / Journal of Organometallic Chemistry 724 (2013) 57e66
4H, PeCH2eCH2e), 1.55 (br, 4H, PeCH2eCH2e), 1.38 (d, 12H,
J ¼ 6.6 Hz, eCH(CH3)2), 1.20 (d, 12H, J ¼ 6.9 Hz, eCH(CH3)2). Anal.
Calcd for C68H72N4P2Pd2S2$0.25CH2Cl2: C, 62.79; H, 5.60; N, 4.29.
Found: C, 62.62; H, 5.53; N, 4.00.
Appendix A. Supplementary material
CCDC 873995e874004 contain the supplementary crystallo-
graphic data for this paper. These data can be obtained free of
charge from The Cambridge Crystallographic Data Centre via www.
ccdc.cam.ac.uk/data_request/cif.
3.2.15. [Pd{(4-MeO)C6H3CH]NeC6H3e2,6-i-Pr2}(NCS)]2(
m-dppb)
(20, 93%)
IR (KBr, cmꢀ1): 1607 (
n
C]N), 2086(
n
N]C]S); 1H NMR (300 MHz
Appendix B. Supplementary material
in CDCl3,
d): 7.84e7.89 (m, 8H, PePh), 7.82 (br, 2H, eCH]N), 7.34e
6
4
3
5
0
0
0
7.45 (m, 14H, PePh, H ), 7.23e7.29 (m, 3H, H , H , H ), 6.46 (dd,
2H, J ¼ 2.1, 2.1 Hz, H5), 6.01 (d, 2H, J ¼ 2.4, 2.1 Hz, H3), 3.36 (hepta,
4H, eCH(CH3)2), 3.02 (s, 6H, eOCH3), 2.37 (br, 4H, PeCH2eCH2e),
1.65 (br, 4H, PeCH2eCH2e), 1.36 (d, 12H, J ¼ 6.9 Hz, eCH(CH3)2),
Supplementary data related to this article can be found online at
http://dx.doi.org/10.1016/j.jorganchem.2012.10.033.
References
1.19 (d, 12H,
J
¼
6.9 Hz, eCH(CH3)2). Anal. Calcd for
C70H76N4O2P2Pd2S2: C, 62.54; H, 5.70; N, 4.17. Found: C, 62.57; H,
5.84; N, 3.88.
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Acknowledgment
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This work was supported by the Project Sponsored by the
Scientific Research Foundation for the Returned Overseas Chinese
Scholars of State Education Ministry (2008), the Scientific Research
Foundation funded by Liaoning Provincial Education Department of
China [No. 2008T073; No. LT2011001], the Natural Science Foun-
dation of Liaoning Province [No. 201102085] and Foundation of 211
Project for Innovative Talents Training, Liaoning University.
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6578e6592.
}
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