Inorganic Chemistry
Article
(d, J = 11.7 Hz, 1H), 7.43−7.39 (m, 1H), 7.35 (t, J = 7.4 Hz, 1H),
7.21−7.16 (m, 4H), 6.98 (t, J = 7.2 Hz, 1H), 2.96−2.92 (m, 2H),
2.74−2.69 (m, 2H), 2.44 (s, 3H) ppm. 13C NMR (125 MHz,
CDCl3): δ 187.7, 142.0, 141.9, 139.1, 135.2, 131.9, 131.2, 128.0,
127.2, 126.9, 126.7, 126.0, 122.8, 113.1, 105.6, 29.9, 27.8, 17.9 ppm.
IR (KBr, disk): ν 3412, 1544, 1490, 1451, 1226, 1108, 728 cm−1.
Anal. Calcd (%) for C18H17NO: C, 82.10, H, 6.51; N, 5.32. Found: C,
82.16, H, 6.55; N, 5.27.
CDCl3): δ 166.1, 157.7, 155.0, 140.8, 134.5, 129.8, 129.4, 129.3,
128.5, 127.3, 126.6, 126.1, 124.2, 121.6, 103.4, 85.8, 29.6, 27.5, 8.7
ppm. IR (KBr, disk): ν 1603, 1589, 1558, 1408, 1153, 1027, 778
cm−1. Anal. Calcd (%) for C27H28BrClIrNO: C, 46.99, H, 4.09; N,
2.03. Found: C, 47.06, H, 4.15; N, 2.00. HRMS (ESI, m/z): 654.0979
[M − Cl]+.
General Procedure for the Oxidative Homocouplings of
Amines. In a typical run, iridium complex 1 (0.5 mol %) and amines
(1.0 mmol) were mixed and stirred at 60 °C for 8 h. An oxygen
balloon was used to charge the reaction tube with oxygen. Then the
reaction was cooled to room temperature, and the resultant mixture
was extracted with diethyl ether and dried over anhydrous Na2SO4.
Solvent was evaporated under vacuum. The residue was purified by
silica column chromatography to give the pure imines (PE/EA/Et3N
= 1:6:0.01).
General Procedure for the Oxidative Cross-Couplings of
Benzyl Alcohols and Amines. In a typical run, iridium complex 1
(0.5 mol %), benzyl alcohols (1.0 mmol), and amines (1.0 mmol)
were mixed and stirred at 60 °C for 8 h. An oxygen balloon was used
to charge the reaction tube with oxygen. Then the reaction was cooled
to room temperature, and the resultant mixture was extracted with
diethyl ether and dried over anhydrous Na2SO4. Solvent was
evaporated under vacuum. The residue was dissolved in hexane and
analyzed by GC-MS.
X-ray Crystallography. Diffraction data of 4 and 5 were collected
on a Bruker Smart APEX CCD diffractometer with graphite-
monochromated Mo Kα radiation (λ = 1.34138 Å). The structures
were solved by direct methods and subsequently refined on F2 using
full-matrix least-squares techniques (SHELXL). SADABS absorption
corrections were applied to the data. All non-hydrogen atoms were
refined anisotropically, and hydrogen atoms were located at calculated
positions. All calculations were performed using the Bruker program
Smart.
L5: Yellow solid, 71.3% isolated yield. 1H NMR (500 MHz,
CDCl3) δ 11.88 (d, J = 11.3 Hz, 1H), 8.03 (d, J = 7.6 Hz, 1H), 7.43
(t, J = 6.7 Hz, 1H), 7.35 (t, J = 7.3 Hz, 1H), 7.30 (d, J = 11.8 Hz, 1H),
7.23 (d, J = 7.8 Hz, 2H), 7.19−7.12 (m, 2H), 6.98 (d, J = 8.7 Hz,
1H), 2.95−2.90 (m, 2H), 2.72−2.67 (m, 2H) ppm. 13C NMR (125
MHz, CDCl3): δ 188.0, 170.6, 142.2, 140.5, 134.9, 132.2, 131.0,
128.0, 126.9, 126.7, 125.6, 123.5, 118.4, 114.7, 106.3, 29.7, 27.8 ppm.
IR (KBr, disk): ν 3408, 1586, 1500, 1458, 1243, 929, 763 cm−1. Anal.
Calcd (%) for C17H14BrNO: C, 62.21, H, 4.30; N, 4.27. Found: C,
62.27, H, 4.27; N, 4.33.
Preparation of Half-Sandwich Iridium Complexes 1−5. The
corresponding β-enaminoketonato ligands (0.2 mmol), [Cp*IrCl2]2
(0.1 mmol), and NaOAc (0.4 mmol) were mixed and stirred at 60 °C
in methanol (10 mL) for 6 h under an inert atmosphere. After being
cooled to room temperature, the reaction mixture was filtered and the
filtrate was concentrated to give the crude products. Pure iridium
complexes were obtained in moderate yields through silica gel column
chromatography (PE/EA = 2:1).
1: Red solid, 68.2% isolated yield. 1H NMR (500 MHz, CDCl3): δ
8.10 (d, J = 7.6 Hz, 1H), 7.59 (d, J = 7.7 Hz, 2H), 7.44 (s, 1H), 7.32
(t, J = 7.4 Hz, 3H), 7.28 (d, J = 6.2 Hz, 1H), 7.17−7.11 (m, 2H),
2.83−2.79 (m, 2H), 2.63−2.59 (m, 2H), 1.37 (s, 15H) ppm. 13C
NMR (125 MHz, CDCl3): δ 165.0, 156.6, 155.4, 140.6, 134.7, 129.5,
128.1, 127.2, 126.5, 125.9, 125.7, 125.2, 103.0, 85.7, 29.6, 27.4, 8.6
ppm. IR (KBr, disk): ν 1603, 1579, 1568, 1411, 1146, 974, 749 cm−1.
Anal. Calcd (%) for C27H29ClIrNO: C, 53.06, H, 4.78; N, 2.29.
Found: C, 53.11, H, 4.75; N, 2.36. HRMS (ESI, m/z): 576.1870 [M
− Cl]+.
ASSOCIATED CONTENT
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sı
* Supporting Information
2: Red solid, 51.5% isolated yield. 1H NMR (500 MHz, CDCl3): δ
8.07 (d, J = 7.5 Hz, 1H), 7.50 (d, J = 8.8 Hz, 2H), 7.38 (s, 1H), 7.31
(s, 1H), 2.77 (d, J = 7.3 Hz, 2H), 2.60−2.55 (m, 2H), 1.36 (s, 15H)
ppm. 13C NMR (125 MHz, CDCl3): δ 164.5, 157.5, 155.3, 150.4,
140.5, 134.8, 129.4, 127.2, 126.5, 125.9, 113.1, 102.8, 85.7, 55.5, 53.5,
29.6, 27.4, 8.6 ppm. IR (KBr, disk): ν 1600, 1582, 1561, 1413, 1174,
1032, 835 cm−1. Anal. Calcd (%) for C28H31ClIrNO2: C, 52.45, H,
4.87; N, 2.18. Found: C, 52.51, H, 4.89; N, 2.15. HRMS (ESI, m/z):
606.1989 [M − Cl]+.
The Supporting Information is available free of charge at
1H and 13C NMR spectra of ligands L1−L5 and iridium
complexes 1−5; HRMS spectra of iridium complexes 1−
5; TGA curves of complexes 1−5; crystallographic data
3: Red solid, 53.3% isolated yield. 1H NMR (500 MHz, CDCl3): δ
8.09 (d, J = 7.6 Hz, 1H), 7.56 (d, J = 8.6 Hz, 2H), 7.38 (s, 1H), 7.34
(t, J = 7.2 Hz, 1H), 7.28 (t, J = 7.4 Hz, 3H), 7.11 (d, J = 7.3 Hz, 1H),
2.82−2.77 (m, 2H), 2.63−2.58 (m, 2H), 1.38 (s, 15H) ppm. 13C
NMR (125 MHz, CDCl3): δ 165.7, 155.1, 140.7, 134.5, 131.0, 129.7,
128.1, 127.3, 127.1, 126.6, 126.0, 117.0, 103.3, 85.7, 29.6, 27.4, 8.7
ppm. IR (KBr, disk): ν 1606, 1589, 1558, 1402, 1143, 1002, 742
cm−1. Anal. Calcd (%) for C27H28Cl2IrNO: C, 50.23, H, 4.37; N, 2.17.
Found: C, 50.30, H, 4.41; N, 2.11. HRMS (ESI, m/z): 610.1482 [M
− Cl]+.
Accession Codes
crystallographic data for this paper. These data can be obtained
Cambridge Crystallographic Data Centre, 12 Union Road,
Cambridge CB2 1EZ, UK; fax: +44 1223 336033.
AUTHOR INFORMATION
■
4: Red solid, 51.9% isolated yield. 1H NMR (500 MHz, CDCl3): δ
8.03 (d, J = 7.6 Hz, 1H), 7.79 (s, 1H), 7.31 (t, J = 8.0 Hz, 1H), 7.25−
7.17 (m, 4H), 7.10−7.03 (m, 2H), 2.78 (t, J = 6.8 Hz, 2H), 2.54 (t, J
= 7.1 Hz, 2H), 2.25 (s, 3H), 1.35 (s, 15H) ppm. 13C NMR (125
MHz, CDCl3): δ 165.5, 157.3, 155.3, 140.8, 134.5, 130.7, 130.1,
129.6, 127.9, 127.2, 126.4, 126.2, 125.9, 125.8, 102.4, 85.7, 29.6, 27.3,
18.4, 8.4 ppm. IR (KBr, disk): ν 1603, 1586, 1561, 1418, 1128, 987,
765 cm−1. Anal. Calcd (%) for C28H31ClIrNO: C, 53.79, H, 5.00; N,
2.24. Found: C, 53.84, H, 5.10; N, 2.18. HRMS (ESI, m/z): 590.2041
[M − Cl]+.
Corresponding Author
Zi-Jian Yao − School of Chemical and Environmental
Engineering, Shanghai Institute of Technology, Shanghai
201418, China; State Key Laboratory of Structural Chemistry,
Fujian Institute of Research on the Structure of Matter, Chinese
Academy of Sciences, Fuzhou, Fujian 350002, China;
5: Red solid, 49.7% isolated yield. 1H NMR (500 MHz, CDCl3): δ
8.07 (d, J = 7.5 Hz, 1H), 7.78 (s, 1H), 7.51 (d, J = 7.9 Hz, 1H), 7.39
(s, 1H), 7.34 (t, J = 7.8 Hz, 1H), 7.26 (d, J = 15.2 Hz, 3H), 7.17 (t, J
= 7.9 Hz, 1H), 7.11 (d, J = 7.3 Hz, 1H), 2.79 (t, J = 6.7 Hz, 2H),
2.63−2.57 (m, 2H), 1.38 (s, 15H) ppm. 13C NMR (125 MHz,
Authors
Xiao-Nan Fan − School of Chemical and Environmental
Engineering, Shanghai Institute of Technology, Shanghai
201418, China
G
Inorg. Chem. XXXX, XXX, XXX−XXX