Organometallics
Article
3H, OCH3). 13C NMR (75 MHz, C6D6): δ 150.7, 148.5, 143.6, 129.8,
126.8, 126.6, 125.4, 120.4, 119.9, 119.6, 118.0, 117.5, 117.2, 117.1,
115.1, 49.8, 32.4, 29.9, 26.7, 23.5, 22.9.
Scheme 6. Reaction with Radical Scavenger
X-ray Crystal Structure Determination. Intensity data were
collected on a Bruker P4 diffractometer with graphite-monochromated
Mo Kα radiation (λ = 0.71073 Å). Crystallographic data for complex
solved by direct methods and refined with full-matrix least squares on
all F2 (SHELXL-97) with non-hydrogen atoms anisotropic. CCDC-
1546801 (2a) contains supplementary crystallographic data for this
paper.
64% (0.49 g). Dec pt: >137 °C. IR (Nujol, cm−1):1894.33 ν(Ni−
H);1580.46 ν(CC). Anal. Calcd for C20H24N4Ni (379.12 g mol−1):
1
C, 63.36; H, 6.38; N, 14.78. Found: C, 63.53; H,6.49; N, 14.91. H
General Procedure for Catalytic Hydrodehalogenation. A
Schlenk tube was charged with NaOtBu (0.15 g, 1.5 mmol). The
substrate (1.0 mmol), internal standard (1.0 mmol), toluene (2 mL),
and a toluene solution of 2b (0.5 mL/0.03 mmol, 0.06 M) were added
in sequence. A solution of (EtO)3SiH (0.2 g, 1.2 mmol) in 0.5 mL of
toluene was added dropwise to this mixture. After it was stirred at 80
°C for 2−8 h, the reaction mixture was quenched with HCl (2 mL, 1
M) and extracted with Et2O (3 mL). The organic layer containing the
product was separated. Conversion was determined by GC.
NMR (300 MHz, C6D6): δ 8.29 (dd, J = 9.0, 1.2 Hz, 1H, Harom), 7.78
(dd, J = 9.0, 1.2 Hz, 1H, Harom), 7.22 (s, 1H, Harom), 7.10 (s, 1H,
Harom), 7.07−7.01 (m, 1H, Harom), 6.97 (d, J = 2.1 Hz, 1H, Harom), 6.85
(dd, J = 7.9, 1.3 Hz, 1H, Harom), 6.82−6.75 (m, 1H, Harom), 6.67−6.54
(m, 1H, Harom), 6.37 (d, J = 2.1 Hz, 1H, Harom), 5.61−5.52 (m, 1H,
CH(CH3)2), 2.93 (s, 6H, N(CH3)2), 1.15 (d, J = 6.8 Hz, 6H,
CH(CH3)2), −20.92 (s, 1H, NiH). 13C NMR (75 MHz, C6D6): δ
151.5, 147.0, 143.2, 127.2, 126.3, 120.8, 120.5, 119.4, 117.6, 116.8,
116.2, 115.8, 114.7, 51.6, 50.9, 33.3, 30.2, 20.0, 14.0, 8.5.
Synthesis of 2c. A 100 mL reaction vessel was charged with 1c
(0.92 g, 2.0 mmol), NaBH4 (0.12 g, 3.0 mmol), and THF (60 mL)
under an N2 atmosphere. The reaction mixture was stirred for 5 h until
the green reaction mixture turned yellow. After removal of the solvent
under vacuum, the yellow residue was washed with n-pentane (30 mL)
and then extracted with Et2O (3 × 20 mL) and filtered through Celite.
2c as orange crystals was obtained from diethyl ether at 0 °C. Dec pt:
>141 °C. Yield: 55% (0.42 g). IR (Nujol, cm−1): 1841.47 ν(Ni−H);
1580.63 ν(CC). Anal. Calcd for C24H24N4Ni (427.17 g mol−1): C,
67.48; H, 5.66; N, 13.12. Found: C, 67.21; H, 5.82; N, 13.01. 1H NMR
(300 MHz, C6D6): δ 8.28 (dd, J = 8.4, 1.5 Hz, 1H, Harom), 7.78 (dd, J
= 8.1, 1.2 Hz, 1H, Harom), 7.25 (d, J = 1.8 Hz, 2H, Harom), 7.19−7.14
(m, 2H, Harom), 7.12−7.07 (m, 3H, Harom), 7.03−6.97 (m, 1H, Harom),
6.84 (d, J = 2.1 Hz, 1H, Harom), 6.80 (dd, J = 8.1, 1.5 Hz, 1H, Harom),
6.77−6.72 (m, 1H, Harom), 6.60−6.53 (m, 1H, Harom), 6.19 (d, J = 2.1
Hz, 1H, Harom), 5.36 (s, 2H, NCH2Ph), 2.84 (s, 6H, N(CH3)2),
−20.63 (s, 1H, NiH). 13C NMR (150 MHz, C6D6): δ 151.1, 146.5,
142.8, 137.8, 128.4, 127.9, 127.4, 127.3, 126.8, 126.0, 120.4, 120.1,
119.0, 117.3, 117.2, 115.9, 115.6, 114.4, 54.1, 51.4, 32.1, 30.1, 22.9,
13.8.
Synthesis of 3b. MeI (0.54 g, 2.0 mmol) in 20 mL of THF was
added to 2b (0.76 g, 2.0 mmol) in 30 mL of THF. The mixture was
stirred at room temperature overnight, and then the solvent was
removed by vacuum. The residue was extracted with Et2O. 3b as green
crystals was obtained from diethyl ether at 0 °C. Yield: 58% (0.59 g).
Dec pt: >165 °C. IR (Nujol, cm−1): 1582.87 ν(CC). Anal. Calcd for
C20H23IN4Ni (505.02 g mol−1): C, 47.57; H, 4.59; N, 11.09. Found: C,
47.41; H, 4.42; N, 11.01. 1H NMR (300 MHz, CDCl3): δ 7.77 (dd, J =
8.4, 1.2 Hz, 1H, Harom), 7.25 (d, J = 1.2 Hz, 1H, Harom), 7.11−7.05 (m,
1H, Harom), 7.03 (d, J = 7.9 Hz, 1H, Harom), 6.87−6.80 (m, 1H, Harom),
6.80−6.74 (m, 2H, Harom), 6.60 (s, 1H, Harom), 6.59−6.52 (m, 1H,
Harom), 6.21 (s, 1H, Harom), 6.13 (m, 1H, CH(CH3)2), 3.22 (s, 3H,
N(CH3)2), 2.65 (s, 3H, N(CH3)2), 1.30−1.25 (m, 6H, CH(CH3)2).
13C NMR (75 MHz, C6D6): 149.9, 147.6, 142.2, 130.7, 127.2, 126.8,
120.6, 120.5, 120.1, 119.6, 118.6, 118.4, 116.8, 116.1, 53.9, 52.4, 49.4,
29.7, 24.8, 22.2.
ASSOCIATED CONTENT
* Supporting Information
The Supporting Information is available free of charge on the
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S
1
Selected crystallographic data and original IR, H NMR,
and 13C NMR spectra of the compounds (PDF)
Accession Codes
CCDC 1546801 contains the supplementary crystallographic
data for this paper. These data can be obtained free of charge
Crystallographic Data Centre, 12 Union Road, Cambridge CB2
1EZ, UK; fax: +44 1223 336033.
AUTHOR INFORMATION
Corresponding Author
ORCID
Notes
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The authors declare no competing financial interest.
ACKNOWLEDGMENTS
This work was supported by NSFC Nos. 21572119/21372143.
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REFERENCES
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(1) Moulton, C. J.; Shaw, B. L. J. Chem. Soc., Dalton Trans. 1976,
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Synthesis of 4b. A 100 mL reaction vessel was charged with 1b
(0.92 g, 2.0 mmol), NaOMe (0.11 g, 3.0 mmol), and THF (60 mL)
under an N2 atmosphere. The reaction mixture was stirred overnight.
After removal of the solvent under vacuum, the residue was washed
with n-pentane and filtered through Celite. 4b as purple crystals was
obtained from n-pentane/water at 0 °C. Dec pt: >148 °C. Yield: 60%
(0.49 g). IR (Nujol, cm−1): 1573.01 ν(CC). Anal. Calcd for
C21H26N4NiO (409.15 g mol−1): C, 61.65; H, 6.41; N, 13.69. Found:
C, 61.51; H, 6.60; N, 13.79. 1H NMR (300 MHz, CDCl3): δ 7.98 (dd,
J = 8.4, 1.2 Hz, 1H, Harom), 7.41 (dd, J = 8.1, 1.2 Hz, 1H, Harom), 7.17−
7.06 (m, 2H, Harom), 7.00 (dd, J = 7.8, 1.2 Hz, 1H, Harom), 6.94−6.87
(m, 1H, Harom), 6.83−6.75 (m, 2H, Harom), 6.63−6.56 (m, 1H, Harom),
6.28 (d, J = 2.1 Hz, 1H, Harom), 6.20 (m, 1H, CH(CH3)2), 3.01 (s, 3H,
N(CH3)2), 2.76 (s, 3H, N(CH3)2), 1.29 (s, 6H, CH(CH3)2), 0.98 (s,
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