Paper
Dalton Transactions
filtered, and dried under vacuum to afford orange yellow (4). The same procedure as 1 was employed except that
powder. Yield: 0.87 g, 53%. 1H NMR spectrum (400 MHz, L4–Na·THF (1.20 g, 1.41 mmol) and trans-NiMeCl(PMe3)2
C6D6, ppm); δ: 7.54 (d, J = 2.5 Hz, 1H, CHvN), 7.43 (d, J = (0.369 g, 1.41 mmol) were used. 4 was obtained as orange
7.6 Hz, 4H, PhH), 7.19 (d, J = 5.3 Hz, 3H, PhH), 7.15–6.99 (m, yellow powder. Yield: 0.656 g, 54%. 1H NMR spectrum
9H, PhH), 6.88–6.83 (m, 6H, PhH), 6.82 (s, 2H, CHPh2), 6.43 (d, (400 MHz, C6D6, ppm); δ: 7.68 (s, 2H, PhH), 7.54 (d, J = 2.7 Hz,
J = 8.7 Hz, 1H, PhH), 5.56 (d, J = 2.5 Hz, 1H, PhH), 3.13 (s, 3H, 1H, PhH), 7.33 (d, J = 7.5 Hz, 4H, PhH), 7.23 (s, 2H, CH), 7.11
Ar–CH3), 1.63 (s, 9H, C(CH3)3), 1.32 (s, 9H, C(CH3)3), 1.01 (s, J = (t, J = 7.6 Hz, 4H, PhH), 7.03 (d, J = 7.3 Hz, 2H, PhH), 6.98–6.92
9.3 Hz, 9H, P(CH3)3), −0.52 (d, J = 6.9 Hz, 3H, Ni–CH3). (m, 4H, PhH), 6.83–6.78 (m, 6H, PhH), 6.29 (d, J = 8.5 Hz, 1H,
13C NMR spectrum (100 MHz, C6D6, ppm); δ: 169.57 (CHvN), CHvN), 5.50 (d, J = 2.7 Hz, 1H, PhH), 1.60 (s, 9H, C(CH3)3),
164.37, 157.17, 145.05, 144.75, 143.03, 140.08, 139.12, 133.74, 1.30 (s, 9H, C(CH3)3), 0.96 (d, J = 9.4 Hz, 9H, P(CH3)3), −0.65
130.46, 130.17, 129.37, 129.33, 128.50, 126.53, 126.33, 125.70, (d, J = 6.6 Hz, 3H, Ni–CH3). 13C NMR spectrum (100 MHz,
119.56, 114.56, 54.57 (OCH3), 53.48 (CHPh2), 35.60, 33.80, C6D6, ppm); δ: 168.49 (CHvN), 164.68, 154.84, 143.63, 142.15,
31.80, 30.05, 14.41 (d, JCP = 26.8 Hz, P(CH3)3), −11.62 (d, JCP
=
140.67, 139.39, 134.08, 130.31, 129.94, 129.88, 129.39, 129.12,
43.7 Hz, Ni–CH3). 31P NMR spectrum (162 MHz, C6D6, ppm); 128.84, 128.77, 128.68, 127.45 (q, JCF = 32 Hz, PhCH–CF3),
δ: −12.82. Anal. Calcd for C52H60NNiO2P: C, 76.10; H, 7.37; 127.00, 126.55, 125.83 (q, JCF = 3.6 Hz, PhCm-ArH), 125.10 (q,
N, 1.71. Found: C, 76.18; H, 7.56; N, 1.71.
JCF = 270 Hz, CF3), 119.18, 53.36 (CHPh2), 35.57, 33.78, 31.69,
[2,4-Di-tert-butyl-6-((2,6-dibenzhydryl-4-methylphenylimino)- 30.00, 23.05, 14.31 (d, JCP = 27.3 Hz, P(CH3)3), −12.48 (d, JCP
=
methyl)-phenolato]-Ni(II)-methyl(trimethylphosphine) (2). The 39.6 Hz, Ni–CH3). 31P NMR spectrum (162 MHz, C6D6, ppm);
same procedure as 1 was employed except that L2–Na·THF δ: −12.49. 19F NMR spectrum (282 MHz, CDCl3, ppm),
(0.894 g, 1.14 mmol) and trans-NiMeCl(PMe3)2 (0.268 g, δ: −61.71. Anal. Calcd for C52H57F3NNiOP: C, 72.73; H, 6.69;
1.14 mmol) were used. 2 was obtained as orange yellow N, 1.63. Found: C, 72.50; H, 6.77; N, 1.69.
powder. Yield: 0.51 g, 56%. 1H NMR spectrum (400 MHz,
[2,4-Di-tert-butyl-6-((2,6-diisopropylphenyliminomethyl)-
C6D6, ppm); δ: 7.54 (d, J = 2.7 Hz, 1H, CHvN), 7.45 (d, J = 7.5 methyl)-phenolato]-Ni(II)-methyl(trimethylphosphine) (5). The
Hz, 4H, PhH), 7.21 (d, J = 2.7 Hz, 3H, PhH), 7.19 (s, 2H, same procedure as 1 was employed except that L5-Na·THF
CHPh2), 7.12–7.00 (m, 9H, PhH), 6.87–6.80 (m, 6H, PhH), 6.43 (0.49 g, 1.00 mmol) and trans-NiMeCl(PMe3)2 (0.26 g,
(d, J = 9.2 Hz, 1H, PhH), 5.56 (d, J = 2.7 Hz, 1H, PhH), 1.91 (s, 1.00 mmol) were used. After the reaction, the reaction mixture
3H, Ar–CH3), 1.64(s, 9H, C(CH3)3), 1.32 (s, 9H, C(CH3)3), 0.99 was filtered over Celite. A dark brown solid was obtained after
(d, J = 9.3 Hz, 9H, P(CH3)3), −0.51 (d, J = 7.6 Hz, 3H, Ni–CH3). the volatiles were removed in vacuo. The solid was dissolved in
13C NMR spectrum (100 MHz, C6D6, ppm); δ: 169.10 (CHvN), ca. 3 mL of hexane, and kept at −30 °C. Some yellow powder
164.38, 149.33, 145.06, 143.19, 139.13, 138.81, 134.50, 133.75, impurity precipitated out of the solution. After filtration, the
130.52, 130.21, 129.64, 129.39, 129.33, 128.50, 128.48, 126.49, filtrate was dried under vacuum to yield 5 as orange yellow
126.28, 119.54, 53.26 (CHPh2), 35.60, 33.80, 31.79, 30.06, powder. Yield: 0.23 g, 43%. 1H NMR spectrum (400 MHz,
21.29, 14.40 (d, JCP = 26.8 Hz, P(CH3)3), −11.77 (d, JCP = 41.3 C6D6, ppm); δ: 7.90 (s, 1H, CHvN), 7.54 (d, J = 2.7 Hz, 1H,
Hz, Ni–CH3). 31P NMR spectrum (162 MHz, C6D6, ppm); δ: PhH), 7.15 (s, 1H, PhH), 7.12 (s, 1H, CH), 7.02 (d, J = 7.5 Hz,
−12.74. Anal. Calcd for C52H60NNiOP: C, 77.61; H, 7.52; 1H, PhH), 6.93 (d, J = 2.7 Hz, 1H, PhH), 4.01 (dt, J = 13.7, 6.9
N, 1.74. Found: C, 77.31; H, 7.56; N, 1.78.
Hz, 2H, CHMe2), 1.60 (s, 9H, C(CH3)3), 1.37 (d, J = 6.9 Hz, 9H,
[2,4-Di-tert-butyl-6-((2,6-dibenzhydryl-4-chlorophenylimino)- P(CH3)3), 1.35 (s, 9H, C(CH3)3), 1.01 (d, J = 6.8 Hz, 12H,
methyl)-phenolato]-Ni(II)-methyl(trimethylphosphine) (3). The CHMe2), −1.06 (s, 3H, Ni–CH3). 13C NMR spectrum (100 MHz,
same procedure as 1 was employed except that L3–Na·THF C6D6, ppm); δ: 168.49 (CHvN), 166.62, 165.70, 149.92, 141.71,
(1.47 g, 1.80 mmol) and trans-NiMeCl(PMe3)2 (0.471 g, 140.31, 139.08, 135.03, 129.30, 128.75, 126.30, 123.63, 119.44,
1.80 mmol) were used. 3 was obtained as yellow powder. Yield: 35.70, 33.98, 31.72, 30.10, 28.56, 14.56 (d, JCP = 25.5 Hz,
0.890 g, 60%. 1H NMR spectrum (400 MHz, C6D6, ppm); δ: P(CH3)3), −12.20 (s, Ni–CH3). 31P NMR spectrum (162 MHz,
7.52 (d, 1H, CHvN), 7.32 (d, 4H, PhH), 7.31 (2, 2H, CHPh), C6D6, ppm); δ: −13.74. Anal. Calcd for C31H50NNiOP: C, 68.65;
7.12 (dd, 6H, PhH), 7.03 (d, 2H, PhH), 6.94 (m, 4H, PhH), 6.79 H, 9.29; N, 2.58. Found: C, 68.20; H, 9.06; N, 2.94.
(m, 6H, PhH), 6.28 (s, 1H, CHvN), 5.49 (d, 1H, PhH), 1.60 (s,
General procedure for high-pressure ethylene polymerization
9H, C(CH3)3), 1.29 (s, 9H, C(CH3)3), 0.98 (s, 9H, P(CH3)3), −0.61
(d, 3H, Ni–CH3). 13C NMR spectrum (100 MHz, C6D6, ppm); In a glove box, a 350 mL Chemglass pressure vessel was
δ: 168.99 (CHvN), 164.57, 150.24, 143.86, 142.33, 141.37, charged with a stir bar, 10 μmol pre-catalyst, 20 μmol
139.29, 133.95, 131.16, 130.37, 129.96, 129.39, 129.02, 128.90, Ni(COD)2 and 50 mL toluene. The pressure vessel was installed
128.69, 128.60, 126.83, 126.47, 119.31, 53.31 (CHPh2), 35.57, on a high-pressure line. The solution was frozen by liquid
33.78, 31.72, 30.01, 14.36 (d, JCP = 27.1 Hz, P(CH3)3), −12.06 (d, nitrogen, evacuated and thawed to room temperature. In the
JCP = 43.2 Hz, Ni–CH3). 31P NMR spectrum (162 MHz, C6D6, case of polymerization in the presence of polar additives, the
ppm); δ: −12.63. Anal. Calcd for C51H57ClNNiOP: C, 74.24; polar additives were injected using a syringe at this stage in
H, 6.96; N, 1.70. Found: C, 74.51, H, 6.98, N, 1.72.
the presence of 1 atm of ethylene. Then the solution was
[2,4-Di-tert-butyl-6-((2,6-dibenzhydryl-4-trifluoromethyl phenyl- brought to the desired temperature and charged with 9 atm of
imino)methyl)-phenolato]-Ni(II)-methyl (trimethyl-phosphine) ethylene. After 10 min, the reactor was vented and 50 mL 7%
Dalton Trans.
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