D. Rix et al. / Journal of Organometallic Chemistry 691 (2006) 5397–5405
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CHvinyl), 7.11 (dd, J(H,H) = 11.3 Hz and J(H,H) =
17.9 Hz, 1H, CHvinyl), 7.39 (d, J(H,H) = 9.1 Hz, 1H,
CHAr), 7.82 (dd, J(H,H) = 2.9 Hz and J(H,H) = 8.8 Hz,
1H, CHAr), 8.13 (d, J(H,H) = 3.1 Hz, 1H, CHar), 8.43 (t,
J(H,H) = 7.3 Hz, 2H, CHPy); 8.89 (tt, J(H,H) = 1.3 Hz
and J(H,H) = 7.9 Hz, 2H, CHPy), 9.38 (m, 1H, CHPy)
13C NMR (100 MHz, (CD3)2CO) d (ppm): 158.5, 147.9
(2C), 146.5 (2C), 131.8, 130.4, 130.0 (2C), 126.3, 124.1,
117.9, 116.1, 72.7, 22.8 (2C). 31P NMR (162 MHz,
(CD3)2CO) d (ppm): À143.2 (sept, 1P, J(F,P) = 707.5 Hz).
19F NMR (376 MHz, (CD3)2CO) d (ppm): À73.0 (d, 6F,
J(F,P) = 707.5 Hz).
(d, J(H,H) = 8.1 Hz, 1H, CHar), 6.98 (dd, J(H,H) =
11.3 Hz and J(H,H) = 17.9 Hz, 1H, CHvinyl), 7.07 (dd,
J(H,H) = 2.2 Hz and J(H,H) = 8.4 Hz, 1H, CHAr), 7.31
(d, J(H,H) = 2.2 Hz, CHAr), 8.05 (t, J(H,H) = 7.1 Hz, 2H,
CHPy), 8.54 (td, J(H,H) = 7.9 Hz and J(H,H) = 1.3 Hz,
2H, CHPy), 8.94 (d, J(H,H) = 5.6 Hz, 1H, CHPy). 13C
NMR (400 MHz, MeOD) d (ppm): 22.9 (2C), 33.1, 34.2,
63.4, 72.6, 114.8, 116.4, 127.7, 129.6, 129.8, 130.3, 133.5
(2C), 133.8, 146.3, 147.2 (2C), 155.5. 31P NMR (162 MHz,
CDCl3) d (ppm): À143.2 (sept, 1P, J(F,P) = 710.1 Hz).
19F NMR (376 MHz, CDCl3) d (ppm): À72.3 (d, 6F,
J(F,P) = 710.1 Hz).
4.2.5. Pyridinium-activated catalyst (7)
4.2.7. Pyridinium non-activated catalyst (15)
In a Schlenk flask, 1-[3-(4-isopropoxy-3-vinylphe-
Grubbs II catalyst 2b (0.069 g, 0.08 mmol), CuCl
(0.012 g, 0.12 mmol) and CH2Cl2 (3.5 mL) were placed in
a Schlenk flask equipped with a condenser. A solution of
12 (0.037 g, 0.096 mmol) in CH2Cl2 (1.3 mL) was then
added and the resulted solution was stirred under argon
at 45 ꢁC for 15 min. From this point forth, all manipula-
tions were carried out in air with reagent-grade solvents.
The reaction mixture was concentrated in vacuo and to
the residue EtOAc (10 mL) was added. The solution was
filtered off. After removal of solvent, the solid was washed
with a small amount of cold n-pentane and dried under
vacuum to give the pyridinium catalyst 7 as olive micro-
crystalline solid (0.067 g, 99%). 1H NMR (400 MHz,
CDCl3) d (ppm): 1.43 (m, 6H, 2CH3), 2.33–2.49 (m, 18H,
6CH3Mes), 4.16 (m, 4H, 2CH2), 4.89 (m, 1H, CH), 7.09
(s, 4H, CHMes), 7.90 (m, 1H, CHAr), 7.99 (m, 2H, CHAr),
8.47 (m, 4H, CHPy), 8.57 (m, 1H, CHPy), 16.58 (s, 1H,
CH). HRMS (FAB) calc. for C+: 704.1748, found:
704.1766.
nyl)propyl]-pyridinium hexafluorophosphate 7 (21.3 mg,
0.05 mmol) was diluted in dry dichloromethane (5 mL).
Copper(I) chloride (5 mg, 0.05 mmol, 1 equiv.) and Grubbs
II catalyst 2b (42.5 mg, 0.05 mmol, 1 equiv.) were intro-
duced. The resulting solution was degassed three times
(vacuum/argon) and stirred for 1 h at 30 ꢁC. The solvent
was evaporated under vacuum, the residue was dissolved
in dry acetone (10 mL) and the insoluble materials were
removed by filtration and washed with acetone
(2 · 5 mL). The filtrate was evaporated under vacuum
and then purified through a plug of silica gel to afford
the pyridinium catalyst 15 as a green powder (37 mg,
83%). 1H NMR (400 MHz, CDCl3) d (ppm): 1.40 (d,
J(H,H) = 6.0 Hz, 6H, 2CH3), 2.24 (m, 2H, CH2), 2.5-2.7
(m, 18H, 6CH3Mes), 3.03 (t, J(H,H) = 7.3 Hz, 2H, CH2),
4.42 (m, 4H, CH2), 5.07 (m, 3H, CH, CH2), 6.82 (d,
J(H,H) = 1.9 Hz, 1H, CHAr), 7.10 (d, J(H,H) = 8.2 Hz,
1H, CHAr), 7.25 (s, 4H, CHMes), 7.65 (dd, J(H,H) = 1.9 Hz
and J(H,H) = 8.2 Hz, CHAr), 8.30 (t, J(H,H) = 6.9 Hz, 2H,
CHPy), 8.78 (t, J(H,H) = 7.8 H, 2H, CHPy), 9.26 (d,
J(H,H) = 6.4 Hz, 1H, CHPy), 16.49 (s, 1H, Ru@CH). 31P
NMR (162 MHz, (CD3)2CO) d (ppm): À143.0 (sept, 1P,
J(F,P) = 708 Hz). 19F NMR (376 MHz, (CD3)2CO) d
(ppm): À72.9 (d, 6F, J(F,P) = 708 Hz).
4.2.6. 1-[3-(4-Isopropoxy-3-vinylphenyl)propyl]-pyridinium
hexafluorophosphate (17)
A 10 mL round bottomed flask equipped with a con-
denser was charged with 4-(3-bromo-propyl)-1-isoprop-
oxy-2-vinyl-benzene 16 [17] (362 mg, 1 mmol), pyridine
(810 lL, 10 mmol, 10 equiv.) and dry toluene (5 mL). The
mixture was stirred overnight at 100 ꢁC then the solvent
was evaporated off. The residue was dissolved in distilled
water (30 mL) and washed with small volume of EtOAc
(3 · 10mL) and then treated with potassium hexafluoro-
phosphate (239 mg, 1.3 mmol, 1.3 equiv.). After 10 min stir-
ring, dichloromethane and brine were added. The organic
phase was washed with brine, dried over magnesium sulfate,
filtrated and concentrated. A purification by silica gel chro-
matography using dichloromethane/acetone (3/1) as the
eluent afforded the desired pyridinium Æ PF6 salt 17 as a pale
yellow solid (324 mg, 76% two steps). 1H NMR (400 MHz,
MeOD) d (ppm): 1.30 (d, J(H,H) = 6.0 Hz, 6H, 2CH3), 2.36
(quint, J(H,H) = 7.5 Hz, 2H, CH2), 2.71 (t, J(H,H) =
7.5 Hz, 2H, CH2), 4.54 (sept, J(H,H) = 6.0 Hz, 1H, CH),
4.66 (t, J(H,H) = 7.5 Hz, 2H, CH2), 5.18 (dd, J(H,H) =
1.2 Hz and J(H,H) = 11.3 Hz, 1H, CHvinyl), 5.72 (dd,
J(H,H) = 1.7 Hz and J(H,H) = 17.8 Hz, 1H, CHvinyl), 6.87
4.3. General procedure for RCM reactions in CH2Cl2
A reaction tube equipped with a magnetic stirring bar
was charged with pyridinium-catalyst 7 (1–5 mol%), sub-
strate (0.2 mmol) and CH2Cl2. The reaction mixture was
stirred at 25 ꢁC. After complete conversion (followed by
TLC), the reaction mixture was passed through a cartridge
containing silica gel (1–2 g). The cartridge was washed with
an additional portion of CH2Cl2 (10–20 mL). The solvent
was removed under reduced pressure to yield crude cyclised
product.
4.4. General procedure for RCM reactions in MeOH/H2O
(5/2 v/v) and EtOH/H2O (5/2 v/v)
A reaction tube equipped with a magnetic stirring bar
was charged with catalyst 7 (6 mg, 0.007 mmol, 5 mol%)