6 of 7
LU ET AL.
To this solution, IPr* (0.92 g, 1.00 mmol) in dry THF
(10 ml) was added. After stirring for 8 hr at 25 C, the
syringe. The mixture was stirred at 0 C for 30 min, and
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then at 50 C for additional 12 hr. After the reaction was
mixture was filtered and evaporated to dryness in
vacuo. The residue was washed with n-hexane
(3 × 10 ml), and recrystallized from THF solution at
quenched by the addition of saturated ammonium chlo-
ride solution, the resulting mixture was extracted with
ethyl acetate (3 × 10 ml), the combined organic layer was
washed with brine (3 × 10 ml), dried over anhydrate
Na2SO4, filtered, and concentrated. The residue was puri-
fied by column chromatography. The GC yield of the
desired product was determined by GC analysis, using n-
dodecane as an internal standard.
0
ꢀC. The complex 1 was precipitated as pink crystals
in a yield of 78% (1.08 g), mp: 180 ꢀC; 1H NMR
(400 MHz, CDCl3): δ 7.66–7.51 (m, 6H), 7.35–7.24 (m,
11H), 7.23–7.14 (m, 7H), 7.11–7.07 (m, 12H), 7.02–6.94
(m, 16H), 6.68–6.66 (m, 8H), 6.12 (s, 4H), 4.37 (s, 2H),
2.40 (s, 6H); 13C NMR (101 MHz, CDCl3): δ 167.0 (d,
J = 132.2 Hz), 166.3, 145.4, 143.6, 143.5, 138.3, 138.2,
135.7, 135.3, 135.2, 132.4, 132.0, 131.0, 130.0, 129.5,
127.9, 127.8, 127.6, 127.5, 125.9, 125.9, 123.4, 123.4,
51.2, 22.1; 31P NMR (162 MHz, CDCl3): δ 16.25; Ele-
mental Analysis (%): calcd. For C87H71Br2N2NiP·0.5THF
(MW 1430.07): C 74.75, H 5.29, N 1.96; found: C 74.47,
H 5.24, N 1.93.
ACKNOWLEDGMENTS
We are grateful to the National Natural Science Founda-
tion of China (Grants 21472134 and 21971183), the Natu-
ral Science Foundation of the Jiangsu Higher Education
Institutions of China (19KJA610001), the Key Laboratory
of Organic Chemistry of Jiangsu Province for financial
support.
CONFLICT OF INTEREST
There are no conflicts to declare.
4.3 | Synthesis of Ni (IPr*)(PCy3)Br2 (2)
A Schlenk flask was charged with 1 (1.40 g, 1.00 mmol),
dry THF (10 ml) and a stirring bar. To this solution, PCy3
(0.28 g, 1.00 mmol) in dry THF (10 ml) was added. After
FUNDING INFORMATION
National Natural Science Foundation of China,
Grant/Award Number: 21472134 and 21971183. Natural
Science Foundation of the Jiangsu Higher Education
ꢀ
stirring for 1 hr at 25 C, the mixture was filtered and
evaporated to dryness in vacuo. The residue was washed
with n-hexane (3 × 10 ml), and recrystallized from tolu-
ene at 0 ꢀC. The complex 2 was precipitated as pink crys-
Institutions
19KJA610001.
of
China,
Grant/Award
Number:
1
tals in a yield of 89% (1.25 g), mp: 172 ꢀC; H NMR
ORCID
(400 MHz, CDCl3): δ 7.51 (s, 7H), 7.25 (s, 18H), 6.99–6.84
(m, 14H), 6.68 (s, 7H), 6.07 (s, 4H), 4.12 (s, 2H), 2.50–2.00
(m, 9H), 1.83 (s, 5H), 1.62 (s, 11H), 1.26–0.89 (m, 11H);
13C NMR (151 MHz, CDCl3): δ 168.0 (d, J = 119.3 Hz),
145.8, 143.8, 143.6, 142.4, 141.8, 140.7, 137.9, 135.5, 131.2,
131.0, 130.3, 129.5, 129.3, 129.1, 128.7, 128.2, 127.8, 127.1,
126.0, 125.9, 125.3, 123.7, 122.8, 51.4, 32.6, 29.8, 27.8,
26.5, 21.88; 31P NMR (162 MHz, CDCl3): δ 10.44; Elemen-
tal Analysis (%): calcd. For C87H89Br2N2NiP
(MW 1412.16): C 74.00, H 6.35, N 1.98; found: C 73.70, H
6.37, N 1.98.
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4.4 | General procedure for the reductive
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In a glovebox, a 10 ml oven-dried Schlenk tube equipped
with a stir bar was charged with aryl chlorides
(2.0 mmol), magnesium turnings (2.8 mmol), THF
(1.8 ml) and a solution of 1 (0.2 ml, 0.01 mol %, prepared
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ture were added benzyl chlorides (2.4 mmol) at 0 C by