4-(2-Hydroxy-2-(3-methoxyphenyl)ethyl)-4-methyl-2,2Ј-
bipyridine (5). The crude product was chromatographed using
ethyl acetate–pentane–Et3N (50 : 48 : 2) to give compound 5 in
46% yield (0.364 g, 1.14 × 10Ϫ3 mol). 1H NMR (CDCl3): δ 8.54
(1H, J = 5.2, d, pyridine), 8.51 (1H, J = 5.2, d, pyridine), 8.31
(1H, s, pyridine), 8.21 (1H, s, pyridine), 7.25 (1H, t, J = 8 Hz,
methoxyphenyl), 7.12 (2H, m, pyridine ϩ methoxyphenyl), 6.94
(2H, m, pyridine ϩ methoxyphenyl), 6.82 (1H, dd, J1 = 8,
J2 = 2.4 Hz, methoxyphenyl), 4.99 (1H, m, benzylic CH(OH)),
3.93 (3H, s, benzylic CH3), 3.08 (2H, m, benzylic CH2) and 2.43
(3H, s, OCH3). 13C NMR: δ 160.0, 156.2, 156.0, 149.2, 149.1,
148.7, 148.5, 145.6, 129.8, 125.2, 125.0, 122.3, 122.2, 118.3,
113.7, 111.4, 74.6, 55.5, 45.6 and 21.4.
tered off, washed with water (100 mL) and diethyl ether (100
mL). The product was dried under reduced pressure during
24 h.
Tris(4-(2-(3-methoxyphenyl)ethenyl)-4Ј-methyl-2,2Ј-
bipyridine)ruthenium bis(hexafluorophosphate) (1). 37% yield
(0.111 g, 85.5 × 10Ϫ6 mol). 1H NMR (CDCl3): δ 8.97 (3H,
pyridine), 8.76 (3H, d, pyridine), 8.04–7.67 (12H, m, methoxy-
phenyl), 7.43–7.34 (15 H, m, methoxyphenyl), 7.26 (3H, m,
methoxyphenyl), 6.94 (3H, m, methoxyphenyl), 3.84 (9H, s,
OCH3) and 2.59 (s, 9H, CH3). Calc. for C60H54F12N6O3P2Ru:
C, 55.52; H, 4.19; N, 6.47. Found: C, 55.83; H, 4.69; N,
6.14%.
Tris(4,4Ј-di(2-(3-methoxyphenyl)ethenyl)-2,2Ј-bipyrid-
ine)ruthenium bis(hexafluorophosphate) (2). Compound 2
was obtained in 41% yield (0.147 g, 86.9 × 10Ϫ6 mol). 1H
NMR (CDCl3): δ 9.15 (6H, m, pyridine), 8.10 (6H, d, J =
6.4, pyridine), 7.83 (6H, d, J = 16.4, vinylic), 7.54 (6H, d, J = 6,
pyridine), 7.46 (6H, d, J = 16.4, vinylic), 7.37 (12H, m, meth-
oxyphenyl), 7.27 (12H, m, methoxyphenyl), 6.99 (6H, dd,
J1 = 7.6, J2 = 1.6 Hz, methoxyphenyl) and 3.86 (18H, s, OCH3).
13C NMR: δ 160.5, 157.7, 151.7, 147.0, 137.6, 136.8, 130.2,
124.7, 121.3, 120.4, 115.5, 112.6 and 55.0. Calc. for C84H72-
F12N6O6P2Ru: C, 61.05; H, 4.39; N, 5.09. Found: C, 60.78; H,
4.65; N, 4.92%.
4,4Ј-Di(2-hydroxy-2-(3-methoxyphenyl)ethyl)-2,2Ј-
bipyridine (6). NMR of the crude product showed more than
85% of conversion compared to the aldehyde and complete
conversion compared to the bipyridine. The crude product 6
1
was used without further purification. H NMR (200 MHz)
(CDCl3): δ 8.37 (2H, d, J = 5, pyridine), 8.21 (2H, broad s,
pyridine), 7.24 (2H, t, J = 8.4, methoxyphenyl), 7.06 (2H, dd,
J1 = 5, J2 = 1.6 Hz, methoxyphenyl), 6.93 (4H, m, methoxy-
phenyl), 6.80 (2H, m, pyridine), 4.98 (2H, m, benzylic
CH(OH)), 3.77 (6H, s, OCH3) and 3.03 (4H, m, benzylic CH2).
13C NMR: δ 159.7, 155.6, 148.9, 148.8, 145.4, 129.5, 125.0,
122.2, 118.1, 113.3, 111.1, 74.2, 55.2 and 45.5.
Heteroleptic complexes. Bis(2,2Ј-bipyridyl)(4-(2-(3-meth-
oxyphenyl)ethenyl)-4Ј-methyl-2,2Ј-bipyridine)ruthenium
bis-
4-(2-(3-Methoxyphenyl)ethenyl)-4Ј-methyl-2,2Ј-bipyridine (7).
Compound 5 (0.367 g, 1.14 × 10Ϫ3 mol) was dissolved in conc.
AcOH (5 mL, excess) and stirred under reflux during 18 hours.
The reaction mixture was poured into sat. aq. NaHCO3 (100
mL) and extracted with CH2Cl2 (100 mL), dried over MgSO4
and concentrated to give 7 in 74% yield (0.255 g, 0.84 ×
10Ϫ3 mol) from 5 and 34% yield from 4,4Ј-dimethyl-2,2Ј-
bipyridine. 1H NMR (CDCl3): δ 8.637 (1H, d, J = 5.2, pyridine),
8.57 (1H, d, J = 4.8, pyridine), 8.51 (1H, d, J = 1.2, pyridine),
8.26 (1H, broad s, pyridine), 7.42 (1H, d, J = 16.4, vinylic), 7.37
(1H, dd, J1 = 5.2, J2 = 1.2, pyridine), 7.31 (1H, t, J = 8, meth-
oxyphenyl), 7.16 (2H, m, methoxyphenyl ϩ pyridine), 7.11
(2H, m, vinylic ϩ methoxyphenyl), 6.88 (1H, dd, J1 = 8, J2 = 2.4
Hz, methoxyphenyl), 3.86 (s, 3H, OCH3) and 2.45 (s, 3H, CH3).
13C NMR: δ 160.2, 156.8, 156.0, 149.7, 149.1, 148.5, 137.9,
133.5, 130.0, 126.7, 125.1, 122.3, 121.2, 120.0, 118.6, 114.7,
112.4, 55.5 and 21.5. Calc. for C28H18N2O: C, 79.44; H, 6.00;
N, 9.26. Found: C, 78.24; H, 6.17; N, 9.63%.
(hexafluorophosphate) (3). [Ru(bpy)2Cl2]14 (0.035 g, 66 × 10Ϫ6
mol) and compound 7 (20 mg, 66 × 10Ϫ6 mol) were stirred at
reflux in a 10 mL mixture of EtOH and water (1 : 1), under
argon for one hour. The solution turned deep red. The EtOH
was distilled off and a solution of NH4PF6 (0.215 g, 1.32 × 10Ϫ3
mol) in water (15 mL) added and stirred overnight (18 h), after
which time an orange precipitate had appeared. The precipitate
was filtered off and dried under vacuum overnight to give 3 in
94% yield (0.063 g, 62.5 × 10Ϫ6 mol). 1H NMR (acetone): δ 9.00
(1H, s, substituted pyridine), 8.84–8.78 (4H, m, non-substituted
bipyridines), 8.70 (1H, s, substituted pyridine), 8.22–8.16 (5H,
m, 4H non-substituted bipyridines ϩ 1H substituted bipyrid-
ines), 8.09–8.04 (5H, m, non-substituted bipyridines ϩ 1H
substituted bipyridines), 7.94 (1H, d, J = 5.6, substituted
pyridine), 7.77 (1H, d, J = 16, vinylic), 7.67 (1H, m, substituted
pyridine), 7.59 (4H, m, non-substituted bipyridines), 7.42 (1H,
d, J = 16 Hz, vinylic), 7.36 (1H, m, methoxyphenyl), 7.23 (2H,
m, methoxyphenyl), 6.98 (1H, m, methoxyphenyl), 3.85 (3H, s,
OCH3), 2.57 (3H, s, py CH3). Calc. for C40H34F12N6OP2Ruؒ
7H2O: C, 42.45; H, 4.27; N, 7.42. Found: C, 41.86; H, 3.79;
N, 8.00%.
4,4Ј-Di(2-(3-methoxyphenyl)ethenyl)-2,2Ј-bipyridine
(8).
Crude compound 6 was dissolved in conc. AcOH (10 mL,
excess) and the mixture stirred under reflux for 18 hours.
When the reaction mixture was cooled to room temperature
the product precipitated and 6 was obtained with a yield of 36%
(0.378 g, 0.898 × 10Ϫ3 mol) from 4,4Ј-dimethyl-2,2Ј-bipyridine.
1H NMR (CDCl3): δ 8.69 (2H, d, J = 4.8, pyridine), 8.61 (2H,
s, pyridine), 7.47 (2H, J = 16.4, d, vinylic), 7.43 (2H, d, J = 4.8,
pyridine), 7.32 (2H, t, J = 7.6 Hz, methoxyphenyl), 7.18 (2H, d,
methoxyphenyl), 7.14 (4H, m, vinylic ϩ methoxyphenyl), 6.90
(2H, m, pyridine) and 3.87 (s, 6H, OCH3). 13C NMR: δ 149.5,
148.9, 133.3, 129.8, 126.4, 124.9, 122.2, 121.1, 119.7, 118.4,
114.5, 112.1, 55.3 and 21.2. IR (KBr): 3306, 2937, 1598, 1487,
1462, 1435, 1263, 1149, 1046, 783 and 700 cmϪ1. Calc. for
C14H12NO: C, 79.98; H, 5.75; N, 6.66. Found: C, 79.11; H, 5.81;
N, 6.56%.
Bis(2,2Ј-bipyridyl)(4,4Ј-di(2-(3-methoxyphenyl)ethenyl)-
2,2Ј-bipyridine)ruthenium
bis(hexafluorophosphate)
(4).
[Ru(bpy)2Cl2]14 (0.025 g, 47.5 × 10Ϫ6 mol) and compound 8
(0.020 g, 66 × 10Ϫ6 mol) were stirred at reflux in a 10 mL
mixture of EtOH and water (1 : 1), under argon for one hour.
The solution turned deep red. The EtOH was distilled off and
a solution of NH4PF6 (0.080 g, 0.48 × 10Ϫ3 mol) in water (10
mL) added and stirred overnight (18 h), after which time an
orange precipitate had appeared. The precipitate was filtered
off and dried under vacuum overnight to afford 4 in 46%
1
yield (0.024 g, 22.3 × 10Ϫ6 mol). H NMR (acetone): δ 9.08
(2H, s, substituted pyridine), 8.84 (4H, d, J = 8.4, non-
substituted bipyridines), 8.23 (4H, t, J = 8, non-substituted
bipyridines), 8.19 (2H, d, J = 5.6, methoxyphenyl), 8.08 (2H,
d, J = 5.6, substituted pyridine), 7.96 (2H, d, J = 6, methoxy-
phenyl), 7.79 (2H, d, J = 16, vinylic), 7.71 (2H, d, J = 6, substi-
tuted pyridine), 7.61 (4H, m, non-substituted bipyridines), 7.45
(2H, d, J = 16 Hz, vinylic), 7.37 (2H, m, methoxyphenyl), 7.27
(4H, m, non-substituted bipyridines), 6.98 (2H, m, methoxy-
phenyl) and 3.86 (6H, s, OCH3). Calc. for C48H40F12N6O2P2-
Ruؒ2Et2O: C, 52.87; H, 4.75; N, 6.61. Found: C, 53.74; H, 4.46;
N, 6.77%.
Homoleptic complexes. RuCl3ؒxH2O (48 mg, 0.23 × 10Ϫ3 mol)
and compound 7 or 8 (0.69 × 10Ϫ3 mol) were stirred at reflux in
a 20 mL mixture of EtOH and water (1 : 1) under nitrogen for
24 hours during which time the solution turned dark red. The
EtOH was distilled off and a solution of NH4PF6 (1.24 g,
7.66 × 10Ϫ3 mol) in water (25 mL) added, after which an
orange-brown precipitate appeared. The precipitate was fil-
1324
J. Chem. Soc., Dalton Trans., 2001, 1319–1325