Organometallics
Article
1 equiv of (COD)PdMeCl with the corresponding ligands in methylene
chloride. The ligand (1 mmol) was added to 10 mL of methylene
chloride in a Schlenk tube under a nitrogen atmosphere. A solution of
(COD)PdMeCl (1 mmol) in CH2Cl2 (10 mL) was added to the above
solution. The resulting mixture was stirred at room temperature for 24 h.
The solvent was evaporated under reduced pressure to afford a solid.
The product was washed with 4 × 20 mL of diethyl ether and dried
under vacuum.
126.70, 125.71, 122.36, 121.67, 121.37, 112.91, 112.87, 110.25, 109.79,
57.12 (OMe), 56.85 (OMe), 29.49, 29.11, 23.97, 23.58, 23.53, 23.11,
4.14 (Pd-Me). Anal. Calcd for C39H47ClN2O2Pd: C, 65.27; H, 6.60; N,
3.90; Found: C, 65.44; H, 6.35; N, 3.67.
General in Situ Activated Polymerization Procedure. A
350 mL glass thick-walled pressure vessel was charged with the required
amount of MAO (for complexes Ni-1−Ni-6) or NaBAF (for complexes
Pd-1−Pd-6), 50 mL of toluene, and a magnetic stir bar in the glovebox.
The pressure vessel was connected to a high-pressure polymerization
line, and the solution was degassed. The vessel was warmed to the
desired temperature using an oil bath and allowed to equilibrate for
10 min. The metal complex was injected to initiate polymerization and
stirred continuously for the desired time. The polymerization was
quenched via the addition of MeOH (5 mL), and the polymer was
precipitated using excess acidic MeOH (5% HCl in MeOH) and dried in
(
4,7‑di‑MeN∧N)PdMeCl (Pd-1). Orange solid. Yield: 77% (528 mg). 1H
NMR (CDCl3, 400 MHz): δ 7.74 (d, J = 16.9 Hz, 2H, aryl-H), 7.54−
7.27 (m, 6H, aryl-H), 6.37 (s, 1H, aryl-H), 6.14 (s, 1H, aryl-H), 3.50−
3.31 (m, 4H, CHMe2), 2.34 (s, 3H, Me), 2.33 (s, 3H, Me), 1.47 (d,
J = 6.6 Hz, 6H, CHMe2), 1.37 (d, J = 6.6 Hz, 6H, CHMe2), 0.96 (d, J =
6.8 Hz, 6H, CHMe2), 0.91 (d, J = 6.8 Hz, 6H, CHMe2), 0.83 (s, 3H, Pd-
Me). 13C NMR (100 MHz, CDCl3): δ 172.52 (NC), 168.07 (NC),
142.38, 141.54, 141.50, 139.51, 139.45, 139.25, 138.40, 131.52, 129.75,
129.26, 128.23, 127.38, 127.13, 126.43, 125.79, 125.57, 124.46, 123.72,
29.19 (Me), 28.71 (Me), 24.22, 23.85, 23.66, 23.40, 22.42, 22.41, 3.12
(Pd-Me). Anal. Calcd for C39H47ClN2Pd: C, 68.31; H, 6.91; N, 4.09;
a vacuum oven to constant weight. BD = 1000 × 2(ICH3)/(3ICH2+CH
+
1
3ICH3). H NMR: CH3 (alkyl methyl, alk-CH3, m, 0.77−0.95 ppm);
CH2 and CH (alk-CH and alk-CH2, m, ca. 1.0−1.45 ppm).
Copolymerization of Ethylene and MA. In a typical procedure, a
50 mL round-bottom Schlenk flask with a stirring bar was heated for 3 h
to 150 °C under vacuum and then cooled to room temperature. The
flask was pressurized to 15 psi of ethylene and vented three times. The
appropriate amounts of CH2Cl2 solvent, MA, and NaBAF were
introduced into the glass reactor under an ethylene atmosphere, and
then a 2 mL solution of the palladium catalyst (30 μmol) in CH2Cl2 was
syringed into the well-stirred solution with the total reaction volume
kept at 25 mL. The ethylene pressure was kept at a constant value of
15 psi by continuous feeding of gaseous ethylene throughout the
reaction. The polymerizations were terminated by the addition of a large
amount of methanol after continuous stirring for 15 h. Then the
methanol was decanted off, and the sticky polymer was redissolved in
hot toluene. The polymer solution was filtered through alumina and
silica to remove catalyst residues. The resulting precipitated polymers
were collected and treated by concentration and drying under vacuum at
40 °C to a constant weight. The MA incorporation (mol %) was
calculated from 1H NMR analysis, as was done before in previous studies
of MA copolymers.22 The branches ending with functional groups are
added to the total branches. MA% = 4IOMe/3(ICH3 + ICH2 + ICH) × 100%.
1H NMR: OMe (s, ca. 3.61−3.76 ppm); CH2 and CH (m, ca. 1.0−1.45
ppm); CH3 (m, 0.77−0.95 ppm).
Found: C, 68.11; H, 7.07; N, 4.28.
(
1
5‑OMeN∧N)PdMeCl (Pd-2). Orange solid. Yield: 75% (514 mg). H
NMR (CDCl3, 400 MHz): δ 8.23 (dd, J = 19.5, 8.3 Hz, 1H, aryl-H), δ
7.45 (dd, J = 15.5, 7.2 Hz, 1H, aryl-H), 7.40−7.28 (m, 6H, aryl-H), 6.72
(t, J = 7.7 Hz, 1H, aryl-H), 6.60 (d, J = 7.7 Hz, 1H, aryl-H), 6.39 (dd, J =
7.7, 3.8 Hz, 1H, aryl-H), 4.00 (d, J = 1.3 Hz, 3H, OMe), 3.61−3.25 (m,
4H, CHMe2), 1.48 (d, J = 6.8 Hz, 6H, CHMe2), 1.37 (d, J = 6.8 Hz, 6H,
CHMe2), 0.94 (ddd, J = 17.5, 9.6, 7.0 Hz, 12H, CHMe2), 0.81 (s, 3H,
Pd-Me). 13C NMR (100 MHz, CDCl3): δ 172.99 (NC), 171.03 (NC),
168.48 (NC), 166.78 (NC), 159.64, 159.19, 145.76, 142.54, 142.40,
141.60, 141.52, 139.85, 139.49, 138.72, 138.39, 128.24, 128.05, 127.82,
127.68, 127.32, 127.27, 127.14, 126.90, 126.70, 126.39, 126.01, 125.52,
125.31, 124.52, 124.49, 123.78, 123.54, 123.44, 119.84, 119.17, 107.07,
107.01, 56.49 (OMe), 56.44 (OMe), 29.20, 29.15, 28.72, 28.67, 24.31, 24.23,
23.93, 23.88, 23.75, 23.67, 23.46, 23.42, 2.90 (Pd-Me), 2.80
(Pd-Me). Anal. Calcd for C38H45ClN2OPd: C, 66.37; H, 6.60; N, 4.07;
Found: C, 66.58; H, 6.39; N, 4.12.
(
5, 6‑diOMeN∧N)PdMeCl (Pd-3). Orange solid. Yield: 71% (509 mg). 1H
NMR (CD2Cl2, 400 MHz): δ 7.52−7.23 (m, 6H, aryl-H), 6.70−6.59
(m, 2H, aryl-H), 6.51 (d, J = 8.2 Hz, 1H, aryl-H), 6.32 (d, J = 8.4 Hz, 1H,
aryl-H), 3.92 (s, 6H, OMe), 3.39 (dtd, J = 20.8 Hz, 13.8 Hz, 6.9 Hz, 4H,
CHMe2), 1.41 (dd, J = 23.1, 6.7 Hz, 12H, CHMe2), 0.96 (dd, J = 15.9,
6.9 Hz, 12H, CHMe2), 0.60 (s, 3H, Pd-Me). 13C NMR (100 MHz,
CD2Cl2): δ 172.15 (NC), 167.85 (NC), 161.83, 161.40, 149.56,
143.03, 141.94, 140.15, 139.16, 128.24, 128.22, 127.74, 127.13, 124.73,
123.96, 119.35, 118.73, 115.31, 107.78, 107.71, 56.90 (OMe), 56.86
(OMe), 29.33, 28.93, 24.23, 23.83, 23.64, 23.47, 1.58 (Pd-Me). Anal.
Calcd for C39H47ClN2O2Pd: C, 65.27; H, 6.60; N, 3.90; Found: C,
ASSOCIATED CONTENT
* Supporting Information
■
S
The Supporting Information is available free of charge on the ACS
Experimental procedures, NMR spectra for ligands,
palladium complexes, polyethylene, and copolymers, and
crystallographic data for complexes Ni-1, Ni-5, Pd-1, and
Crystallographic data for complexes Ni-1, Ni-5, Pd-1, and
65.52; H, 6.43; N, 3.65.
1
(
3‑OMeN∧N)PdMeCl (Pd-4). Orange solid. Yield: 77% (528 mg). H
NMR (CD2Cl2, 400 MHz): δ 8.09 (dd, J = 17.3, 9.1 Hz, 1H, aryl-H),
7.95 (dd, J = 15.3, 8.0 Hz, 1H, aryl-H), 8.03−7.89 (m, 8H, aryl-H), 6.52,
6.32 (d, J = 7.3, 7.4 Hz, 1H, aryl-H), 3.45−3.21 (m, 4H, CHMe2), 3.31
(d, J = 2.5 Hz, 3H, OMe), 1.47−1.32 (m, 12H, CHMe2), 0.96 (ddd, J =
24.8, 12.3, 5.4 Hz, 12H, CHMe2), 0.62, 0.45 (s, 3H, Pd-Me). 13C NMR
(100 MHz, CD2Cl2): δ 173.63 (NC), 170.75 (NC), 169.25 (NC),
166.24 (NC), 155.29, 155.22, 146.31, 145.56, 145.17, 143.00, 142.11,
140.24, 139.72, 139.29, 138.83, 126.21, 126.14, 125.99, 125.75, 125.63,
124.82, 124.01, 122.47, 121.80, 116.28, 111.60, 111.09, 57.28 (OMe),
57.01 (OMe), 29.50, 29.35, 29.16, 28.92, 24.20, 23.96, 23.81, 23.65,
23.56, 23.48, 23.44, 23.09, 4.11 (Pd-Me), 2.32 (Pd-Me). Anal. Calcd for
C38H45ClN2OPd: C, 66.37; H, 6.60; N, 4.07; Found: C, 66.54; H, 6.35;
N, 3.97.
AUTHOR INFORMATION
Corresponding Author
■
Notes
The authors declare no competing financial interest.
(
3, 8‑diOMeN∧N)PdMeCl (Pd-5). Orange solid. Yield: 69% (495 mg). 1H
ACKNOWLEDGMENTS
■
NMR (CD2Cl2, 400 MHz): δ 7.97 (dd, J = 16.0, 9.0 Hz, 2H, aryl-H),
7.38−7.07 (m, 6H, aryl-H), 6.94 (t, J = 9.3 Hz, 2H, aryl-H), 3.35 (dt, J =
13.7, 6.8 Hz, 4H, CHMe2), 3.25 (s, 6H, OMe), 1.42(d, J = 6.7 Hz, 6H,
CHMe2), 1.38 (d, J = 6.7 Hz, 6H, CHMe2), 0.99 (d, J = 2.0 Hz,
6H, CHMe2), 0.98 (d, J = 2.0 Hz, 6H, CHMe2), 0.34 (s, 3H, Pd-Me).
13C NMR (100 MHz, CD2Cl2): δ 171.53 (NC), 166.87 (NC),
155.98, 155.92, 148.42, 146.00, 145.78, 140.16, 139.24, 134.96, 134.36,
This work was supported by National Natural Science
Foundation of China (NSFC, 21374108, 51522306), the
Fundamental Research Funds for the Central Universities
(WK3450000001), and the Recruitment Program of Global
Experts. We thank Dr. S. M. Zhou (HFNL, USTC) for the
determination of the crystal structures.
G
Organometallics XXXX, XXX, XXX−XXX