FULL PAPER
H, CH3), 3.93 (s, 2 H, CH2), 4.07 (s, 2 H, CH2), 5.03 (sept, J =
6.0 Hz, 2 H, CH), 6.37 (m, J = 7.6 Hz, 1 H, Py), 6.43 (d, J =
spectroscopy. The mixture was filtered with a glass filter (G4) and
Celite. The filtrate was concentrated in vacuo and allowed to stand
7.6 Hz, 1 H, Py), 6.60 (m, 2 H, Py), 6.72 (t, J = 7.7 Hz, 1 H), 6.96– to give 7 as yellow crystals (22 mg, 35%). 1H NMR (CDCl3, Me4Si,
7.18 (m, 8 H, Py), 7.60 (d, J = 7.6 Hz, 4 H, Py), 8.09 (d, J = 7.9 Hz,
2 H), 8.65 (d, J = 5.0 Hz, 2 H) ppm.
300 MHz): δ = 0.83 (d, J = 7.2 Hz, 6 H, CH3), 0.94 (d, J = 6.9 Hz,
6 H, CH3), 1.78 (m, 2 H, CH), 3.38 (s, 2 H, CH2), 6.0 (br., 1 H,
CH2), 6.89 (d, J = 7.9 Hz, 2 H), 7.06 (td, J = 7.2, 1.0 Hz, 2 H, Py),
7.20–7.30 (m, 5 H), 7.40 (dd, J = 7.3, 1.5 Hz, 2 H, Py), 7.62–7.72
(m, 3 H), 7.84 (d, J = 7.6 Hz, 1 H, Py), 7.92 (d, J = 7.6 Hz, 2 H),
9.12 (dd, J = 5.8, 1.5 Hz, 2 H) ppm. 13C NMR (CDCl3, Me4Si,
75.6 MHz): δ = 18.18 (2 C, iPr, CH3), 18.71 (2 C, iPr, CH3), 34.95
(2 C, iPr, CH), 42.30 (CH2), 89.10 (C-OH, q), 95.11 (C-OH, q),
117.55 (2 C, CH), 122.22 (2 C, CH), 123.42 (2 C, CH), 124.37 (2
C, CH), 125.06 (CH), 125.52 (CH), 127.22 (q, 3 C), 128.18 (q, 1
C), 128.49 (2 C, CH), 131.58 (2 C, CH), 139.45 (2 C, CH), 140.54
(CH), 153.48 (q), 153.62 (2 C, CH), 158.23 (q), 158.29 (q), 160.66
Synthesis of the Titanium Complex 6a: The volatiles, including free
propan-2-ol, were removed in vacuo from the toluene solution of
complex 5a (1.18 mmol) obtained above. The residue was again dis-
solved in toluene (2 mL), and 2,2Ј-biphenol (219 mg, 1.18 mmol)
was added. The yellow solution turned dark orange, and after it
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had been stirred at room temp. for 1 h. H NMR observation re-
vealed that isopropoxy groups had been quantitatively replaced
with biphenoxy moieties. The mixture was filtered and hexane
(0.25 mL) was slowly added to the filtrate. The title compound 6a
was obtained as orange block crystals (433 mg, 56%). 1H NMR
(CDCl3, Me4Si, 300 MHz, 60 °C): δ = 0.74 (d, J = 6.9 Hz, 6 H,
CH3), 0.91 (d, J = 6.9 Hz, 6 H, CH3), 1.63 (sept, J = 6.9 Hz, 2 H,
CH), 3.53 (s, 2 H, CH2), 4.06 (s, 2 H, CH2), 6.57 (dd, J = 7.9,
1.0 Hz, 2 H, Py), 6.85 (td, J = 7.5, 1.2 Hz, 2 H, Py), 7.02–7.18 (m,
6 H), 7.30 (dd, J = 7.6, 1.7 Hz, 2 H, Py), 7.50–7.60 (m, 5 H), 8.74
(d, J = 4.8 Hz, 2 H, Py) ppm. 13C NMR (CDCl3, 75.6 MHz): δ =
18.87 (2 C, iPr, CH3), 19.30 (2 C, iPr, CH3), 35.77 (2 C, iPr, CH),
(q, 1 C) ppm. IR (KBr): ν = 644, 675, 721, 760, 880, 949, 1026,
˜
1096, 1130, 1180, 1234, 1273, 1435, 1466, 1489, 1543, 1570, 1601,
1655, 1686, 1701, 1720, 2345, 2380, 3653, 3676, 3807, 3823, 3842,
3857, 3873, 3904 cm–1. Elemental analysis did not give satisfactory
results despite our attempts, probably because of the instability of
the compound. The product was structurally characterized by X-
ray diffraction analysis.
42.71 (CH2), 47.51 (CH2), 86.06 (C-OH, q), 89.33 (C-OH, q), Heck Reactions Catalyzed by Ti–Pd Heterobimetallic Complex: A
118.12 (2 C, CH), 120.10 (2 C, CH), 122.08 (2 C, CH) 122.11 (2
C, CH), 124.04 (CH), 125.24 (CH), 127.58 (2 C, CH), 127.58 (q,
typical procedure is as follows. Titanium(IV) isopropoxide (6 μL,
0.02 mmol) was added to a solution of ligand 4a (8 mg, 0.02 mmol)
overlapped, 2 C), 128.93 (q, 2 C), 131.34 (2 C, CH), 137.83 (2 C, in DMF (2 mL) in a 20 mL Schlenk tube and the mixture was
CH), 138.09 (CH), 147.57 (2 C, CH), 158.01 (q), 160.72 (q), 163.24
stirred for 0.5 h at room temp. Bis(benzonitrile)palladium(II) chlor-
ide (8 mg, 0.02 mmol) was added, and the mixture was stirred for
0.5 h. Acrylic acid (144 mg, 2.0 mmol), iodobenzene (408 mg,
(q, 2 C) ppm. IR (KBr): ν = 621, 644, 667, 690, 717, 756, 876, 941,
˜
1037, 1099, 1153, 1230, 1277, 1431, 1470, 1489, 1574, 1593, 2878,
2959, 3059 cm–1. C37H37N3O4Ti (635.6): calcd. C 69.92, H 5.87, N 2.0 mmol), and triethylamine (414 mg, 4.2 mmol) were added to
6.61; found C 69.92, H 5.82, N 6.61.
this reddish brown solution, and the mixture was stirred at 140 °C
for 2 h. The reaction mixture was diluted with diethyl ether and
dilute HCl was added. The mixture was extracted with diethyl
ether/dichloromethane (10:1). The organic layers were combined,
washed with water, and dried with magnesium sulfate. Volatiles
were removed in vacuo to leave the crude product as a brownish
solid (291 mg crude). The solid was dissolved in CDCl3 and mea-
sured by 1H NMR with use of toluene (1.0 mmol) as internal stan-
dard to determine the yield of cinnamic acid (81%).
Synthesis of the Titanium Complex 6b: Ti(O-iPr)4 (59 μL,
0.20 mmol) was added at room temp. to a solution of the O,N,O–
N,N ligand 4b (94 mg, 0.20 mmol) in toluene (1.5 mL). The mixture
was stirred for 1 h at room temp. 2,2Ј-Biphenol (37 mg, 0.20 mmol)
was added to the mixture at room temp. The mixture was stirred
for an additional 1 h at room temperature. The product was recrys-
tallized by adding n-hexane (0.2 mL). The title compound was ob-
tained as orange crystals (105 mg, 75%). 1H NMR ([D8]toluene,
Me4Si, 300 MHz, 80 °C): δ = 3.88 (s, 2 H, CH2), 4.10 (s, 2 H, CH2),
6.37 (d, J = 7.9 Hz, 1 H, Py), 6.53 (m, 3 H, CH), 6.44 (dd, J = 7.9,
X-ray Diffraction Analyses of the Titanium Complex 6a: Crystals
were obtained by evaporation of solvent from a dichloromethane
1.4 Hz, 2 H, CH), 6.77 (t, J = 7.9 Hz, 1 H, Py), 6.91–7.09 (m, 6 solution.
H), 7.33 (d, J = 1.4 Hz, 2 H, CH), 7.36 (d, J = 2.1 Hz, 2 H, CH),
A yellow block crystal (0.15ϫ0.10ϫ0.10 mm) was
mounted on a polyamide film (MicroMountsTM, MiTegen) and
7.46 (dd, J = 7.6, 1.7 Hz, 2 H, CH), 7.49 (dt, J = 7.90, 0.90 Hz, 2 coated with paraffin. All data were collected with a Rigaku Mer-
H, Py), 8.56 (m, 2 H) ppm. 13C NMR (CDCl3, Me4Si, 75.6 MHz, cury CCD area detector and use of graphite-monochromated Mo-
60 °C): δ = 47.77 (CH2), 50.94 (CH2), 87.14 (q, C-OH), 87.17 (q, Kα radiation (λ = 0.71073 Å) at 153 K. The structure was solved
C-OH), 117.80 (2 C, CH), 120.55 (2 C, CH), 122.00 (2 C, CH), by direct methods[9] and expanded by use of Fourier techniques.[10]
122.20 (2 C, CH), 124.51 (C, CH), 125.38 (CH), 125.74 (CH), The non-hydrogen atoms were refined anisotropically. Hydrogen
126.15 (2 C, Ph, CH), 126.64 (4 C, Ph, CH), 127.55 (2 C, Ph, CH),
atoms were refined by use of the riding model. The cell units consist
127.55 (q, overlapped, 2 C), 127.79 (2 C, CH), 128.29 (2 C, CH), of two crystallographically independent molecules of 6a, which
128.53 (q, 2 C), 129.10 (1 C, CH), 131.21 (2 C, CH), 137.86 (q, 2 have fundamentally identical structures. The final cycle of full-ma-
C), 138.54, (CH), 147.76 (2 C, CH), 158.07 (q, Py), 158.96 (q, Py), trix, least-squares refinement on F2 was based on 14560 observed
163.07 (q, 2 C, Py) ppm. IR (KBr): ν = 625, 648, 675, 694, 718, reflections and 819 variable parameters. All calculations were per-
˜
756, 876, 949, 1038, 1096, 1146, 1231, 1277, 1431, 1470, 1489, 1570, formed by use of the CrystalStructure[11] crystallographic software.
1597, 2280, 2345, 2372, 2515, 2870, 3020, 3059, 3402, 3634, 3653,
Crystallographic data are summarized in the Supporting Infor-
3738, 3753, 3807, 3842, 3857, 3903 cm–1. C43H33N3O4Ti (703.7): mation. CIF data were deposited in the Cambridge Structural
calcd. C 73.40, H 4.73, N 5.97; found C 73.14, H 4.82, N 5.84.
Database (CCDC-1019249).
Synthesis of the Heterobimetallic Complex 7: The titanium complex
6a (54 mg, 0.077 mmol) was dissolved in dichloroethane (4 mL),
and to this solution PdCl2(PhCN)2 (31 mg, 0.081 mmol) was
added. The mixture was stirred at room temp. for 1 h, and quanti-
X-ray Diffraction Analyses of the Titanium Complex 6b: Crystals
were obtained by recrystallization from a toluene solution. A yel-
low block crystal (0.30ϫ0.30ϫ0.15 mm) was mounted on a poly-
amide film (MicroMountsTM, MiTegen) and coated with paraffin.
All data were collected with a Rigaku Mercury 70 CCD area detec-
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tative formation of the title compound was observed by H NMR
Eur. J. Inorg. Chem. 2015, 5480–5487
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