Efficient cross-coupling of aryl chlorides with arylzinc reagents catalyzed by amido pincer complexes of nickel

Article abstract of DOI:10.1021/ol701927g

The nickel-catalyzed Negishi cross-coupling reaction of aryl chlorides with arylzinc compounds was investigated. The nickel complexes with the amido pincer type of ligands exhibited high catalytic activity and good functional group tolerance.

Full text of DOI:10.1021/ol701927g

Supporting Information
Efficient Cross-Coupling of Aryl Chlorides with Arylzinc Reagents
Catalyzed by Amido Pincer Complexes of Nickel
Li Wang and Zhong-Xia Wang*
Deaprtment of Chemistry, University of Science and Technology of China,
Hefei, Anhui 230026, P. R. China
Experimental procedures and spectral data
General
All reactions were performed under nitrogen atmosphere using standard Schlenk and vacuum
line techniques. THF and Et2O were distilled under nitrogen over sodium/benzophenone and
degassed prior to use. NMP was dried over 4A molecular sieve, fractionally distilled under
reduced pressure and stored under nitrogen atmosphere. LiBun and CDCl3 was purchased
from Acros Organics and used as received. 2-Furyllithium and 2,6-dimethoxyphenyllithium
were prepared from furan or 1,3-dimethoxybenzene by direct lithiation using LiBun.1,2 PhLi,
p-MeC6H4Li, o-MeC6H4Li and p-Me2NC6H4Li were prepared from corresponding aryl
bromides and Li according to literature.3 NMR spectra were recorded on a Bruker av300
1
spectrometer at ambient temperature. The chemical shifts of the H and 13C NMR spectra
were referenced to internal solvent resonances or TMS. HRMS was determined on a
Agilent6890/Micromass GCT-MS spectrometer.
Reaction of PhZnCl with p-Me2NC6H4Cl catalyzed by complexes 1a−4
1. Preparation of a solution of PhZnCl in THF
Phenyllithium prepared from PhBr (2 g, 12.8 mmol) and Li (0.2 g, 28.5 mmol) in Et2O
(10 mL) was added dropwise to a stirred solution of ZnCl2 (1.73 g, 12.9 mmol) in THF (15
mL) at 0 °C. The mixture was warmed to room temperature and stirred for 1 h. Solvents were
removed under reduced pressure and the residue was dissolved in 25.6 mL of THF to afford a
THF solution of PhZnCl (0.5 M).
2. Reaction of PhZnCl with p-Me2NC6H4Cl catalyzed by complex 1b (entry 2, Table 1)
A Schlenk tube was charged p-Me2NC6H4Cl (0.0778 g, 0.5 mmol), NMP (1.5 mL) and
complex 1b (0.0029 g, 0.005 mmol). To the stirred mixture PhZnCl solution (1.5 mL, 0.5 M
1

solution in THF, 0.75 mmol) was added by syringe. Then the reaction mixture was stirred in
a 70 °C oil bath for 30 h. The solution was cooled to room temperature, and water (10 mL)
and several drops of hydrochloric acid were successively added. The resulting mixture was
extracted with Et2O (10 mL × 3), and the extracts were combined, washed with water (10 mL
× 2), dried (MgSO4), and concentrated. The residue was charged to column chromatography
(silica gel), eluted with a mixture of CH3COOEt and petroleum ether (1:20), and collected the
composition including reaction product and unreacted starting materials. Solvents were
1
removed by rotary evaporation and the residue was determined by H NMR spectrum. The
conversion of p-Me2NC6H4Cl was calculated based on the integration ratio of the NMR
signals of NMe2 groups of the unreacted p-Me2NC6H4Cl and the coupling product in the
mixture.
Reaction of PhZnCl with p-Me2NC6H4Cl catalyzed by each of complexes 1a and 2a−4
followed the same procedure.
Reaction of PhZnCl with p-Et2NC(O)C6H4Cl catalyzed by complex 4 (entry 9, Table 2)
A Schlenk tube was charged p-Et2NC(O)C6H4Cl (0.106 g, 0.5 mmol), NMP (1.5 mL)
and a solution of complex 4 in THF (0.085 mL, prepared by dissolving 0.0091 g of 4 in 20
mL of THF). To the stirred mixture PhZnCl solution (1.5 mL, 0.5 M solution in THF, 0.75
mmol) was added by syringe. Then the reaction mixture was stirred in a 70 °C oil bath for 10
h. The solution was cooled to room temperature, and water (10 mL) and several drops of
hydrochloric acid were successively added. The resulting mixture was extracted with Et2O
(10 mL × 3), and the extracts were combined, washed with water (10 mL × 2), dried (MgSO4),
and concentrated. The residue was purified by column chromatography (silica gel, eluted
using 10 % CH3COOEt in petroleum ether) to afford colorless oil, which solidified after
several days (0.1256 g, 99 %).
Reaction of other arylzinc reagents with aryl chlorides catalyzed by 3b or 4 followed the
same procedure. Colors, melting points (for solid products), and spectral data of the
compounds obtained was listed as follows:
1. N,N-Diethyl-4'-methylbiphenyl-4-carboxamide
N
O
2

White solid, m.p. 68−70 °C.
1H NMR (CDCl3): δ 1.05 (b, 3H, CH3), 1.12 (b, 3H, CH3), 2.28 (s, 3H, Me), 3.21 (b, 2H,
CH2), 3.44 (b, 2H, CH2), 7.14 (d, J = 7.8 Hz, 2H, C6H4), 7.32 (d, J = 8.1 Hz, 2H, C6H4), 7.37
(d, J = 7.8 Hz, 2H, C6H4), 7.48 (d, J = 8.1 Hz, 2H, C6H4).
13C NMR (CDCl3): δ 12.95, 14.24, 21.05, 39.41, 43.49, 126.80, 126.87, 129.53, 135.51,
137.37, 137.46, 141.94, 171.30.
HRMS: calcd. for C18H21NO (M+): 267.1623; found: 267.1615.
2. (4'-Methylbiphenyl-4-yl)(phenyl)methanone
O
White solid. m.p. 129−130 °C (lit. 4 129−130 °C).
1H NMR (CDCl3): δ 2.34 (s, 3H, CH3), 7.22 (d, J = 7.8 Hz, 2H, Ar), 7.40−7.55 (m, 5H, Ar),
7.61 (d, J = 8.4 Hz, 2H, Ar), 7.76 (d, J = 7.2 Hz, 2H, Ar), 7.81 (d, J = 8.4 Hz, 2H, Ar).
3. 4'-Methylbiphenyl-4-carbonitrile
C
N
White solid. m.p. 110−111 °C (lit. 5 110−111 °C).
1H NMR (CDCl3): δ 2.42 (s, 3H, CH3), 7.29 (d, J = 7.2 Hz, 2H, C6H4), 7.49 (d, J = 7.2 Hz,
2H, C6H4), 7.65−7.72 (m, 4H, C6H4).
4. 4-Methylbiphenyl
White solid. m.p. 48−49 °C (lit.6 49−50 °C).
1H NMR (CDCl3): δ 2.54 (s, 3H, CH3), 7.37 (d, J = 7.5 Hz, 2H, Ar), 7.44 (t, J = 7.5 Hz, 1H,
Ar), 7.55 (t, J = 7.5 Hz, 2H, Ar), 7.62 (d, J = 8.1 Hz, 2H, Ar), 7.70 (d, J = 8.1 Hz, 2H, Ar).
5. 4-Methoxy-4'-methylbiphenyl
3

O
White solid. m.p. 111−112 °C (lit.7 109 °C).
1H NMR (CDCl3): δ 2.39 (s, 3H, CH3), 3.85 (s, 3H, OCH3), 6.97 (d, J = 8.7 Hz, 2H, C6H4),
7.23 (d, J = 8.1 Hz, 2H, C6H4), 7.45 (d, J = 8.1 Hz, 2H, C6H4), 7.52 (d, J = 8.7 Hz, 2H, C6H4).
6. (4'-Methylbiphenyl-2-yl)(phenyl)methanone
O
White solid. m.p. 79−80 °C (lit.8 79−80 °C).
1H NMR (CDCl3): δ 2.17 (s, 3H, CH3), 6.93 (d, J = 8.1 Hz, 2H, Ar), 7.08 (d, J = 8.1 Hz, 2H,
Ar), 7.21 (t, J = 7.8 Hz, 2H, Ar), 7.33−7.41 (m, 4H, Ar), 7.46−7.51 (m, 1H, Ar), 7.59 (d, J =
7.5 Hz, 2H, Ar).
7. (4-(Furan-2-yl)phenyl)(phenyl)methanone
O
O
Yellowish solid. m.p. 80−82 °C.
1H NMR (CDCl3): δ 6.51 (dd, J = 1.5, 3.3 Hz, 1H, furyl), 6.81(d, J = 3 Hz, 1H, furyl), 7.49 (t,
J = 7.2 Hz, 2H, Ar), 7.53 (d, J = 1.5 Hz, 1H, furyl), 7.56−7.61 (m, 1H, Ar), 7.75−7.87 (m, 6H,
Ar).
13C NMR (CDCl3): δ 107.48, 112.18, 123.42, 128.39, 130.00, 130.90, 132.39, 134.52, 135.98,
137.88, 143.34, 152.98, 196.04.
HRMS: calcd. for C17H12O2 (M+): 248.0837; found: 248.0839.
8. 2-(4-Methoxyphenyl)furan
O
O
4

White solid. m.p. 54−55 °C (lit.9 54−55 °C).
1H NMR (CDCl3): δ 3.83 (s, 3H, CH3), 6.45 (dd, J = 1.8, 3.3 Hz, 1H, furyl), 6.52 (d, J = 3.3
Hz, 1H, furyl), 6.93 (d, J = 8.8 Hz, 2H, C6H4), 7.43 (b, 1H, furyl), 7.61 (d, J = 8.8 Hz, 2H,
C6H4).
9. N,N-Diethylbiphenyl-4-carboxamide
N
O
White solid. m.p. 58−60 °C.
1H NMR (CDCl3): δ 1.17−1.28 (m, 6H, CH3), 3.33 (b, 2H, CH2), 3.56 (b, 2H, CH2),
7.34−7.39 (m, 1H, Ar), 7.43−7.48 (m, 4H, Ar), 7.58−7.63 (m, 4H, Ar).
13C NMR (CDCl3): δ 13.01, 14.22, 39.42, 43.48, 126.88, 127.10, 127.67, 128.85, 135.97,
140.33, 142.03, 171.20.
HRMS: calcd. for C17H19NO (M+): 253.1467; found: 253.1460.
10. Biphenyl-4-yl(phenyl)methanone
O
White solid. m.p. 105−106 °C (lit.10 106 °C).
1H NMR (CDCl3): δ 7.42 (d, J = 10.2 Hz, 1H, Ar), 7.46−7.53 (m, 4H, Ar), 7.60 (d, J = 7.2 Hz,
1H, Ar), 7.66 (d, J = 7.2 Hz, 2H, Ar), 7.71 (d, J = 8.4 Hz, 2H, Ar), 7.83−7.86 (m, 2H, Ar),
7.90 (d, J = 8.1 Hz, 2H, Ar).
11. 4-Methoxybiphenyl
O
White solid. m.p. 91−92 °C (lit.11 91.1-92.3°C).
1H NMR (CDCl3): δ 3.86 (s, 3H, CH3), 6.98 (d, J = 8.7 Hz, 2H, Ar), 7.31 (t, J = 7.2 Hz, 1H,
Ar), 7.42 (t, J = 7.2 Hz, 2H, Ar), 7.52−7.57 (m, 4H, Ar).
5

12. Ethyl 4'-methylbiphenyl-4-carboxylate
O
O
White solid. m.p. 76−77 °C (lit.12 80−80.5 °C).
1H NMR (CDCl3): δ 1.34 (t, J = 7.1 Hz, 3H, CH3), 2.33 (s, 3H, CH3), 4.32 (q, J = 7.1 Hz, 2H,
CH2), 7.19 (d, J = 8.6 Hz, 2H, Ar), 7.45 (d, J = 8.1 Hz, 2H, Ar), 7.56 (d, 2H, J = 8.5 Hz, Ar),
8.02 (d, 2H, J = 8.5 Hz, Ar).
13. 4-Methyl-4'-(trifluoromethyl)biphenyl
CF3
White solid. m.p. 121 °C (lit.13 121 °C).
1H NMR (CDCl3): δ 2.42 (s, 3H, CH3), 7.29 (d, J = 7.8 Hz, 2H, C6H4 ), 7.50 (d, J = 7.8 Hz,
2H, C6H4), 7.68 (s, 4H, C6H4).
14. 2-p-Tolylpyridine14
N
Colorless oil.
1H NMR (CDCl3): δ 2.41 (s, 3H, CH3), 7.17−7.22 (m, 1H, pyridyl), 7.28 (d, J = 8 Hz, 2H, Ar),
7.69−7.76 (m, 2H, pyridyl), 7.89 (d, J = 8.1 Hz, 2H, Ar), 8.67 (d, 1H, J = 4.6 Hz, pyridyl).
15. 2-Methoxy-4'-methylbiphenyl
O
White solid. m.p. 79−80 °C (lit.15 79−80 °C).
1H NMR (CDCl3): δ 2.37 (s, 3H, CH3), 3.78 (s, 3H, CH3), 6.94−7.02 (m, 2H, Ar), 7.20 (d, J =
7.8 Hz, 2H, Ar), 7.29 (d, J = 7.1 Hz, 2H, Ar), 7.41 (d, J = 8 Hz, 2H, Ar).
16. (2'-Methylbiphenyl-4-yl)(phenyl)methanone
6

O
White solid. m.p. 102−104 °C (lit.16 ).
1H NMR (CDCl3): δ 2.23 (s, 3H, CH3), 7.17−7.22 (m, 4H, Ar), 7.37 (d, J = 8.4 Hz, 2H, Ar),
7.43 (t, J = 7.5 Hz, 2H, Ar), 7.53 (t, J = 7.5 Hz, 1H, Ar), 7.77−7.81 (m, 4H, Ar).
17. Ethyl 2'-methylbiphenyl-4-carboxylate17
O
O
Colorless oil.
1H NMR (CDCl3): δ 1.34 (t, J = 7.2 Hz, 3H, CH3), 2.19 (s, 3H, CH3), 4.34 (q, J = 7.2 Hz, 2H,
CH2), 7.13−7.21 (m, 4H, C6H4), 7.33 (d, J = 8.4 Hz, 2H, C6H4), 8.02 (d, J = 8.4 Hz, 2H,
C6H4).
18. N,N-Diethyl-2'-methylbiphenyl-4-carboxamide
N
O
White solid. m.p. 82−84 °C.
1H NMR (CDCl3): δ 1.15 (b, 6H, CH3), 2.20 (s, 3H, CH3), 3.28 (b, 2H, CH2), 3.50 (b, 2H,
CH2), 7.15−7.20 (m, 4H, C6H4), 7.27 (d, J = 7.8 Hz, 2H, C6H4), 7.36 (d, J = 7.8 Hz, 2H,
C6H4).
13C NMR (CDCl3): δ 13.06, 14.28, 20.46, 39.35, 43.41, 125.86, 126.23, 127.57, 129.23,
129.71, 130.45, 135.30, 135.67, 141.16, 142.91, 171.29.
HRMS: calcd. for C18H21NO (M+): 267.1623; found: 267.1620.
19. 4'-Methoxy-2-methylbiphenyl18
7

O
Colorless oil.
1H NMR (CDCl3): δ 2.27 (s, 3H, CH3), 3.85 (s, 3H, CH3), 6.95 (d, J = 8.4 Hz, 2H, C6H4),
7.21−7.26 (m, 6H, C6H4).
20. (2'-Methylbiphenyl-2-yl)(phenyl)methanone19
O
1
Colorless oil. H NMR (CDCl3): δ 2.14 (s, 3H, CH3), 7.00−7.08 (m, 4H, Ar), 7.28−7.35 (m,
3H, Ar), 7.40−7.48 (m, 2H, Ar), 7.53−7.61 (m, 4H, Ar).
21. (4'-(Dimethylamino)biphenyl-4-yl)(phenyl)methanone
N
O
Yellow solid. m.p. 182−183 °C (lit.20 184.5 °C).
1H NMR (CDCl3): δ 3.03 (s, 6H, CH3), 6.82 (d, J = 8.9 Hz, 2H, Ar), 7.49 (t, J = 7.7 Hz, 2H,
Ar), 7.57−7.60 (m, 3H, Ar), 7.67 (d, 2H, J = 8.3 Hz, Ar), 7.81−7.88 (m, 4H, Ar).
22. N,N-Dimethylbiphenyl-4-amine
N
White solid. m.p. 121−122 °C (lit.21 121−122 °C).
1H NMR (CDCl3): δ 2.92 (s, 6H, CH3), 6.74 (d, J = 8.7 Hz, 2H, Ar), 7.15−7.20 (m, 1H, Ar),
7.32 (t, J = 7.5 Hz, 2H, Ar), 7.43 (d, J = 8.7 Hz, 2H, Ar), 7.49 (d, J = 7.5 Hz, 2H, Ar).
23. 4'-Methoxy-N,N-dimethylbiphenyl-4-amine
8

O
N
White solid. m.p. 151−152 °C (lit.22 150.5−152.3 °C).
1H NMR (CDCl3): δ 2.98 (s, 6H, CH3), 3.84 (s, 3H, CH3), 6.80 (d, J = 8.7 Hz, 2H, Ar), 6.94
(d, J = 8.7 Hz, 2H, Ar), 7.46 (t, J = 8.1 Hz, 4H, Ar).
24. Ethyl 4-(furan-2-yl)benzoate9
O
O
O
Yellowish oil.
1H NMR (CDCl3): δ 1.40 (t, J = 7.2 Hz, 3H, CH3), 4.38 (q, J = 7.2 Hz, 2H, CH2), 6.48−6.52
(m, 1H, furyl), 6.78 (d, J = 3.3 Hz, 1H, furyl), 7.52 (s, 1H, furyl), 7.72 (d, J = 8.1 Hz, 2H,
C6H4), 8.06 (d, J = 8.1 Hz, 2H, C6H4).
25. 4-(Furan-2-yl)benzonitrile
N
C
O
White solid. m.p. 65−66 °C (lit.23 65−66 °C).
1H NMR (CDCl3): δ 6.53 (dd, J = 1.8, 3.3 Hz, 1H, furyl), 6.81 (d, J = 3.3 Hz, 1H, furyl), 7.54
(d, J = 1.8 Hz, 1H, furyl), 7.65 (d, J = 8.4 Hz, 2H, Ar), 7.75 (d, J = 8.4 Hz, 2H, Ar).
26. 2-(4-(Trifluoromethyl)phenyl)furan
O
CF3
White solid. m.p. 88−89 °C (lit.9 88−89 °C).
1H NMR (CDCl3): δ 6.51 (dd, J = 1.8, 3.3 Hz, 1H, furyl), 6.77 (d, J = 3.3 Hz, 1H, furyl ),
7.52 (d, 1H, furyl), 7.63 (d, J = 8.4 Hz, 2H, C6H4), 7.76 (d, J = 8.4 Hz, 2H, C6H4).
27. 2-(Furan-2-yl)pyridine24
O
N
9

Colorless oil.
1H NMR (CDCl3): δ 6.53 (dd, J = 1.5, 3.3 Hz, 1H, furyl), 7.06 (d, J = 3.3 Hz, 1H, furyl),
7.12−7.17 (m, 1H, pyridyl), 7.53 (s, 1H, furyl), 7.67−7.74 (m, 2H, pyridyl), 8.59 (d, J = 4.8
Hz, 1H, pyridyl).
28. 2-Phenylfuran25
O
Colorless oil.
1H NMR (CDCl3): δ 6.50 (dd, J = 1.5, 3.3 Hz, 1H, furyl), 6.68 (d, J = 3.3 Hz, 1H, furyl), 7.28
(t, J = 7.5 Hz, 1H, Ar), 7.41 (t, J = 7.5 Hz, 2H, Ar), 7.50 (d, J = 1.5 Hz, 1H, furyl), 7.71 (d, J
= 7.5 Hz, 2H, Ar).
29. (2',6'-Dimethoxybiphenyl-4-yl)(phenyl)methanone
O
O
O
White solid. m.p. 142−144 °C.
1H NMR (CDCl3): δ 3.69 (s, 6H, OCH3), 6.61 (d, J = 8.4 Hz, 2H, Ar), 7.25 (t, J = 8.4 Hz, 1H,
Ar), 7.39−7.45 (m, 4H, Ar), 7.52 (t, J = 7.2 Hz, 1H, Ar), 7.78−7.81 (m, 4H, Ar).
13C NMR (CDCl3): δ 56.07, 104.42, 118.65, 128.35, 129.50, 129.76, 130.15, 131.19, 132.23,
135.76, 138.20, 139.31, 157.72, 196.71.
HRMS: calcd. for C21H18O3 (M+): 318.1256; found: 318.1251.
30. 1,4-Di(furan-2-yl)benzene
O
O
Pelter, Andrew; Rowlands, Martin; Clements, Gillian; SYNTBF; Synthesis; EN; 1; 1987;
51-53.
White solid. m.p. 148−150 °C (lit.25 148−150 °C).
10

1H NMR (CDCl3): δ 6.49 (dd, J = 1.8, 3.3 Hz, 2H, furyl), 6.68 (d, J = 3.3 Hz, 2H, furyl), 7.48
(d, J = 1.8 Hz, 2H, furyl), 7.69 (s, 4H, C6H4).
31. 1,4-Di(o-methylphenyl)benzene
White solid. m.p. 142−143 °C (lit.26 145.5−146 °C).
1H NMR (CDCl3): δ 2.27 (s, 6H, CH3), 7.15−7.22 (m, 8H, C6H4), 7.28 (s, 4H, C6H4).
32. 1,2-Di(p-methylphenyl)benzene
White solid. m.p. 94−95 °C (lit.27 94−95 °C).
1H NMR (CDCl3): δ 2.32 (s, 6H, CH3), 7.04 (s, 8H, C6H4), 7.40 (s, 4H, C6H4).
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