Organometallics
Article
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13
1
aliphatic region could be assigned. H NMR (300 MHz, CD Cl ): δ
Hz, 1H, CH ), 4.35 (s, 3H, NCH ), 0.05 (s, 3H, Pd−CH ). C{ H}
2
2
pyr
3
3
4
.28 (s, 3H, NCH ), 2.45 (s, 3H, Pd−NCCH ), 0.48 (s, 3H, Pd−
NMR (100 MHz, d -DMSO): δ 170.3 (CO), 151.8 (CPYA), 149.0
3
3
6
CH ).
(CHpyr), 147.4 (Cpyr), 144.2 (CHPYA), 143.7 (CHPYA), 140.4 (CHpyr),
140.4 (CHPYA), 127.9 (CHpyr), 126.8 (CHPYA), 124.9 (CHpyr), 44.7
(NCH ), 1.1 (Pd−CH ).
3
Compound 8. Compound 8 was prepared according to the general
procedure from 5. Yield: 92 mg, 71%. HR-MS: m/z calculated for
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3
+
1
C H N OPd [M − PF ] , 375.0437; found, 375.0412. Anal. Calcd
Compound 12. H NMR (300 MHz, d -DMSO): δ 9.22 (bs, 1H,
6
15
17
4
6
3
for C H F N OPPd·0.25CH Cl : C, 33.80; H, 3.25; N, 10.34.
CH ), 8.93 (bs, 1H, CH ) 8.51 (bs, 1H, CHPYA), 8.29 (t, J
=
15
17
6
4
2
2
pyr
PYA
HH
3
3
Found: C, 34.25; H, 3.39; N, 9.95. Spectroscopic data for the trans
7.8 Hz, 1H, CH ), 8.15 (d, J = 7.8 Hz, 1H, CH ), 7.91 (t, J
pyr HH pyr HH
1
3
isomer are as follows. H NMR (300 MHz, CD Cl ): δ 8.55 (s, 1H,
= 7.8 Hz, 1H, CH ), 7.83 (bs, 1H, CH ), 7.88 (d, J = 8.3 Hz,
pyr PYA HH
2
2
1
3
1
CHPYA), 8.42−8.39 (m, 1H, CH ), 8.24−8.19 (m, 2H, CH
+
1H, CHPYA), 4.17 (s, 3H, NCH ), − 0.12 (s, 3H, Pd−CH ). C{ H}
pyr
pyr
3
3
3
CHPYA), 8.17−8.12 (m, 1H, CH ), 8.07 (t, J = 7.7, Hz, 1H,
NMR (100 MHz, d -DMSO): δ 158.6 (C ), 150.4 (Cpyr), 149.8
PYA
HH
6 PYA
3
3
CH ), 7.87 (dd, J = 8.2, 6.0 Hz, 1H, CHPYA), 7.65 (ddd, J
=
(CHpyr), 146.1 (CHPYA), 144.7 (CHPYA), 141.0 (CH ), 128.2
(CHpyr), 127.9 (CHPYA), 125.6 (CHPYA), 123.1 (CHPYA), 43.1
pyr
HH
HH
pyr
4
7
.5, 5.2, J = 1.5 Hz, 1H, CHpyr), 4.35 (s, 3H, NCH ), 2.27 (s, 3H,
Pd−NCCH ), 0.89 (s, 3H, Pd−CH ). C{ H} NMR (100 MHz,
CD Cl ): δ 156.9 (CH ), 143.9 (CHPYA), 137.9 (CHPYA), 128.1
CH ), 127.3 (CH ), 126.6 (CH ), 126.0 (CHPYA), 125.6
CHpyr), 49.3 (NCH ), 3.7 (Pd−NCCH ), 1.2 (Pd−CH ).
Spectroscopic data for the cis isomer are as follows. H NMR (300
HH
3
1
3
1
3
3
(NCH ), 1.1 (Pd−CH ).
3
3
2
2
pyr
Ethylene/Methyl Acrylate (MA) Copolymerization Reac-
(
tions. All catalytic experiments were performed using a Buchi
̈
pyr
PYA
pyr
(
“tinyclave” reactor equipped with an interchangeable 50 mL glass
vessel. The vessel was loaded with the desired complex (21 μmol),
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3
3
1
MHz, CD Cl ): δ 9.06 (s, 1H, CH ), 8.42−8.39 (m, 1H, CH ),
TFE (21 mL) or distilled CH Cl (22 mL), and MA (1.13 mL). The
2 2
2
2
PYA
pyr
3
8
.17−8.12 (m, 2H, CH
+ CH ), 8.09 (d, J = 6.1 Hz, 1H,
reactor was then placed in a preheated oil bath and connected to the
ethylene tank. Ethylene was bubbled for 10 min, and the reactor was
pressurized. The reaction mixture was stirred at constant temperature.
After the appropriate time, the reactor was cooled to room
temperature and vented. An aliquot (200 μL) of the reaction mixture
was withdrawn and diluted in MeOH (1 mL) for GC-MS analysis.
The reaction mixture was poured into a 50 mL round-bottomed flask
with the CH Cl (3 × 1 mL) used to wash the glass vessel. Volatiles
PYA
pyr
HH
3
3
CH ), 8.06 (t, J = 7.7, Hz, 1H, CH ), 7.85 (dd, J = 7.7, 5.2
Hz, 1H, CHPYA), 7.55 (ddd, J = 7.5, 5.7, J = 1.7 Hz, 1H,
PYA
HH
pyr
HH
3
4
HH
HH
CH ), 4.33 (s, 3H, NCH ), 2.44 (s, 3H, Pd−NCCH ), 0.32 (s, 3H,
pyr
3
3
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Pd−CH ). C{ H} NMR (100 MHz, CD Cl ): δ 150.8 (CH ),
3
2
2
pyr
1
44.7 (CHPYA), 141.4 (CHPYA), 140.4 (CHpyr), 130.9 (CH ), 136.9
pyr
(
CHPYA), 125.5 (CHPYA), 127.2 (CH ), 49.0 (NCH ), 4.2 (Pd−
pyr
3
NCCH ), −0.5 (Pd−CH ).
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3
2
2
Compound 9. Compound 9 was prepared according to the general
procedure from 6. Yield: 85 mg, 65%. HR-MS: m/z calculated for
C H N OPd [M − PF ] , 375.0437; found, 375.0418. Spectro-
scopic data for the trans isomer are as follows. H NMR (300 MHz,
were removed under reduced pressure, and the residue was dried to
constant weight and analyzed by using NMR spectroscopy.
+
Quantification of the low-molecular-weight products from
coplymerization reactions was performed by GC-MS using an Agilent
GC 7890 instrument equipped with a DB-225 ms column (J&W, 60
m, 0.25 mm i.d., 0.25 mm film) and He as carrier coupled with a 5975
MSD. Before analysis, samples were diluted with methanol, and
nonane was added as an internal standard. Quantification of the
products (butenes, hexenes, octenes, and methyl pentenoates) was
done using adequate standard solutions prepared in 2,2,2-trifluor-
oethanol/MA and diluted in methanol containing nonane as internal
standard. Calibration curves were obtained using at least five points in
the concentration range required for accurate determination of the
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17
4
6
1
3
CD Cl ): δ 8.45−8.40 (m, 2H, CH + CH ), 8.23 (dd, J = 8.0,
2
2
pyr
PYA
HH
4
3
4
J
= 1.6 Hz, 1H, CH ), 8.19 (td, J = 8.4, J = 1.4 Hz, 1H,
HH
PYA HH HH
3
4
CH ), 8.15−8.12 (m, 1H, CH ), 7.78 (dd, J = 8.4, J = 1.7
Hz, 1H, CH ), 7.66 (dd, J = 8.0, J = 1.6 Hz, 1H, CHPYA), 7.44
pyr
PYA
HH
HH
3
4
pyr
HH
HH
3
4
(
(
td, J = 8.4, J = 1.4 Hz, 1H, CH ), 4.24 (s, 3H, NCH ), 2.16
HH HH pyr 3
1
3
1
s, 3H, Pd−NCCH ), 1.01 (s, 3H, Pd−CH ). C{ H} NMR (100
MHz, CD Cl ): δ 167.5 (CO), 160.0 (C ), 155.6 (CPYA), 147.6
CH ), 144.5 (CH ), 143.9 (CHPYA), 140.6 (CHPYA), 128.3
CHPYA), 127.3 (CHPYA), 126.3 (CHpyr), 121.0 (CHpyr), 44.4
NCH ), 3.2 (Pd−NCCH ), 2.6 (Pd−CH ). Spectroscopic data for
the cis isomer are as follows. H NMR (300 MHz, CD Cl ): δ 8.47
3
3
2
2
pyr
(
(
(
pyr pyr
2
products, with the regression coefficient R ≥ 0.995. The analysis of
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3
3
1
each sample was repeated at least four times.
2
2
3
4
(
dt, J
= 5.0, J
= 1.6 Hz, 1H, CH ), 8.45−8.40 (m, 1H,
In Situ Ethylene Dimerization Reactions. Ethylene was
bubbled for 5 min into a 10 mM solution of palladium complexes
HH
HH
pyr
3
4
CHPYA), 8.33 (td, J = 7.3, J = 1.6 Hz, 1H, CH ), 8.12−8.07
HH
HH
pyr
3
4
1
(
1
7
m, 2H, CHpyr + CH ), 7.72 (ddd, J = 7.3, 5.0, J = 1.6 Hz,
7−9 in CD
2
Cl
2
in an NMR tube. Then, H NMR spectra were
PYA
HH
HH
3
4
H, CH ), 7.66 (dd, J = 8.4, J = 1.4 Hz, 1H, CH ), 7.64−
recorded at 298 K immediately afterward and at selected times. For
the low-temperature experiments, the tube was cooled to −50 °C (for
7) and −30 °C (for 8), respectively. NOESY experiments were
performed using the standard parameters and a mixing time of 500
ms.
pyr
HH
HH
pyr
.60 (m, 1H, CHPYA), 4.19 (s, 3H, NCH ), 2.45 (s, 3H, Pd−
3
1
3
1
NCCH ), 0.10 (s, 3H, Pd−CH ). C{ H} NMR (100 MHz,
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3
CD Cl ): δ 171.5 (CO), 160.2 (C ), 150.5 (CPYA), 148.3 (CHpyr),
2
2
pyr
1
45.9 (CH ), 144.1 (CHPYA), 140.2 (CHpyr), 129.1 (CHPYA), 129.1
pyr
(
(
CH ), 125.9 (CHPYA), 123.2 (CHPYA), 121.9 (CCH3CN), 44.4
1-Hexene Dimerization Catalysis. 1-Hexene (19.2 mol, 1.92
mol or 19.2 mmol) was added to a solution of complex 9 (1 mg, 1.92
pyr
NCH ), 3.9 (Pd−NCCH ), −5.0 (Pd−CH ).
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3
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General Procedure for the Formation of Palladium
mmol) in 1 mL of CH Cl . The reaction mixture was stirred at 30 °C
2 2
1
Complexes 10−12. Compounds 7−9 were dissolved in deuterated
DMSO to afford 10−12 with the presence of only the cis isomer. The
complexes were only characterized spectroscopically.
for 18 h. The crude mixture was analyzed by H NMR spectroscopy
and GC-MS.
Crystal Structure Determination. Crystal data for trans-7 were
collected on a Oxford Diffraction SuperNova area-detector diffrac-
tometer using mirror optics monochromated Mo Kα radiation (λ =
1
3
Compound 10. H NMR (300 MHz, d -DMSO): δ 9.25 (d, J
=
6
HH
3
5
.2 Hz, 1H, CH ), 8.71 (d, J = 6.5 Hz, 2H, CH ), 8.25 (td,
pyr HH PYA
3
4
3
4
29
JHH = 7.7, J = 1.6 Hz, 1H, CH ), 8.16 (dt, J = 7.7, J = 1.6
0.71073 Å) that was Al filtered. The unit cell constants and an
HH
pyr
HH
HH
3
4
Hz, 1H, CH ), 7.85 (ddd, J = 7.7, 5.2, J = 1.6 Hz, 1H, CHpyr),
7
Pd−CH ). C{ H} NMR (100 MHz, d -DMSO): δ 169.6 (CO),
1
orientation matrix for data collection were obtained from a least-
squares refinement of the setting angles of reflections in the range 2.5°
< θ < 27.8°. A total of 626 frames were collected using ω scans, with
60 + 60 s exposure time, a rotation angle of 1.0° per frame, and a
crystal−detector distance of 65.0 mm, at T = 123(2) K. Data
pyr
HH
HH
3
.75 (d, J = 6.5, 2H, CH ), 4.21 (s, 3H, NCH ), 0.17 (s, 3H,
HH PYA 3
13
1
3
6
62.8 (C ), 151.9 (C ), 148.9 (CHpyr), 144.6 (CHPYA), 140.4
PYA pyr
(
(
CHpyr), 128.0 (CHpyr), 125.5 (CHPYA), 125.3 (CHpyr), 46.4
30
NCH ), 1.1 (Pd−CH ).
reduction was performed using the CrysAlisPro program. The
intensities were corrected for Lorentz and polarization effects, and an
absorption correction based on the multiscan method using SCALE3
ABSPACK in CrysAlisPro was applied. The structure was solved by
direct methods using SHELXS-97 and refined by full-matrix least-
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3
1
3
Compound 11. H NMR (300 MHz, d -DMSO): δ 9.24 (d, J
.2 Hz, 1H, CH ), 8.85 (s, 1H, CH ) 8.69 (d, J = 6.0 Hz, 1H,
=
6
HH
3
5
pyr PYA HH
3
4
3
CHPYA), 8.24 (td, J = 7.7, J = 1.6 Hz, 1H, CH ), 8.19 (d, J
HH
HH
pyr
HH
3
=
8.4 Hz, 1H, CHPYA), 8.12 (d, J = 7.7 Hz, 1H, CH ), 8.06 (dt,
HH pyr
3
3
4
2
31
JHH = 8.4, 6.0 Hz, 1H, CHPYA), 7.85 (ddd, J = 7.7, 5.2, J = 1.6
squares fitting on F for all data using SHELXL-97. Hydrogen atoms
HH
HH
I
Organometallics XXXX, XXX, XXX−XXX