Organometallics
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N, 16.55; S, 6.31. Found: C, 37.15; H, 2.99; N, 15.99; S, 6.11. IR (KBr,
cm−1): 3148w ν(Carom−H), 1518s ν(CN), 1286vs, 1114s, 1073s
ν(SO3). 1H NMR (CD3OD, 298 K): δ 4.99s (6H, C6H6), 5.13dd (3H,
stirred 30 min. Then Li[TpmsPh] (0.528 g, 1.0 mmol) was added to
the solution. After 24 h stirring at room temperature and 24 h stirring
at reflux, a red-brown precipitate formed, which was removed by
filtration, dried under vacuum, and identified as the derivative 6. It is
soluble in acetone and acetonitrile. Yield: 0.44 g, 58%. Mp: 320 °C
dec. Anal. Calcd for C34H27ClN6O3SRu (Mw 736.21 g mol−1): C,
55.47; H, 3.70; N, 11.42; S, 4.36. Found: C, 55.21; H, 3.77; N, 11.13;
S, 4.35. IR (KBr, cm−1): 3186w ν(Carom−H), 1533s ν(CN), 1291vs,
1245vs, 1193vs, 1051vs ν(SO3). 1H NMR (acetone-d6, 298 K): δ 5.25s
(6H, C6H6), 6.49d (3H, 4-H (pz)), 7.34−7.30 m (9H, m-H and p-H
(Ph)), 7.53d (6H, o-H (Ph)), 9.21d (3H, 5-H (pz)). 1H NMR
(acetone-d, 273 K): δ 5.25s (6H, C6H6), 6.49d (3H, 4-H (pz)), 7.34−
7.30 m (9H, m-H and p-H (Ph)), 7.53d (6H, o-H (Ph)), 9.21d (3H, 5-
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4-H (pz)), 7.31d (3H, 3-H (pz)), 7.36d (3H, 5-H (pz)). H NMR
(CD3OD, 273 K): δ 4.99s (6H, C6H6), 5.13dd (3H, 4-H (pz)), 7.31d
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(3H, 3-H (pz)), 7.36d (3H, 5-H (pz)). H NMR (CD3OD, 253 K): δ
4.99s (6H, C6H6), 5.13dd (3H, 4-H (pz)), 7.31d (3H, 3-H (pz)),
7.36d (3H, 5-H (pz)). 1H NMR (CD3OD, 233 K): δ 4.99s (6H,
C6H6), 5.13dd (3H, 4-H (pz)), 7.31d (3H, 3-H (pz)), 7.36d (3H, 5-H
1
(pz)). H NMR (CD3OD, 213 K): δ 4.99s (6H, C6H6), 5.13dd (3H,
4-H (pz)), 7.31d (3H, 3-H (pz)), 7.36d (3H, 5-H (pz)). 13C{1H}
NMR (CD3OD, 298 K): δ 90.2 (s, C6H6), 109.3 (s, 4-C (pz)), 137.4
(s, 5-C (pz)), 149.8 (s, 3-C (pz)). ESI+-MS (CH3CN): m/z 472
[Ru(benzene)(Tpms)]+.
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H (pz)). H NMR (acetone-d6, 253 K): δ 5.25s (6H, C6H6), 6.49d
Synthesis of [Ru(HMB)(Tpms)]Cl (3). [RuCl(HMB)(μ-Cl)]2
(0.334 g, 0.5 mmol) was dissolved in methanol (20 mL), the solution
stirred for 30 min, and then Li[Tpms] (0.300 g, 1.0 mmol) was added
to the red solution, which immediately changed to orange. After 24 h
stirring at room temperature the solvent was removed in vacuo, the
residue redissolved in dichloromethane (10 mL), and the solution
filtered to remove lithium chloride. The solution was then evaporated
to dryness and redissolved in diethyl ether (5 mL). Slow evaporation
afforded a brown powder, which was dried under reduced pressure and
identified as 3. It is very soluble in alcohols, chlorinated solvents,
acetone, and acetonitrile and only slightly soluble in water. Yield: 0.39
g, 62%. Mp: 250 °C dec, color changed from yellow to gray. Anal.
Calcd for C22H27ClN6O3SRu·1/2CH2Cl2 (Mw 634.54 g mol−1): C,
42,59; H, 4.45; N, 13.24; S, 5.05. Found: C, 42.91; H, 4.82; N, 13.54;
S, 4.99. IR (KBr, cm−1): 3185w, 3132w, ν(Carom−H), 1520s ν(CN),
1291vs br, 1114s, 1057s ν(SO3). 1H NMR (CD3OD, 298 K): δ, 2.40s
(18H, C6-(CH3)6), 6.74dd (3H, 4-H (pz)), 8.52d (3H, 3-H (pz)),
8.94d (3H, 5-H (pz)). 13C{1H} NMR (CD3OD, 298 K): δ 16.93 (s,
C6-(CH3)6), 98.71 (s, C6-(CH3)6), 109.6 (s, 4-C (pz)), 138.0 (s, 5-C
(pz)), 147.6 (s, 3-C (pz)).
Synthesis of [Ru(p-cymene)(Tpms)]BF4 (4). A mixture of com-
pound 1 (0.580 g, 1 mmol) and silver tetrafluoroborate, AgBF4 (0.194
g, 1 mmol), was stirred in chloroform (10 mL) for 24 h at room
temperature. The silver chloride precipitate was separated by filtration.
Then the solvent was removed in vacuo, and the residue redissolved in
dichloromethane (10 mL) and hexane. Slow evaporation yielded a
yellow crystalline powder, identified as 4. It is very soluble in water,
alcohols, chlorinated solvents, acetone, and acetonitrile. Yield: 0.30 g,
48%. Mp: 300 °C dec. Anal. Calcd for C20H23N6O3SRuBF4 (Mw
615.37 g mol−1): C, 39.04; H, 3.77; N, 13.66; S, 5.21. Found: C, 38.65;
(3H, 4-H (pz)), 7.34−7.30 m (9H, m-H and p-H (Ph)), 7.53d (6H, o-
H (Ph)), 9.21d (3H, 5-H (pz)). 1H NMR (acetone-d6, 233 K): δ 5.25s
(6H, C6H6), 6.49d (3H, 4-H (pz)), 7.34−7.30 m (9H, m-H and p-H
(Ph)), 7.53d (6H, o-H (Ph)), 9.21d (3H, 5-H (pz)). 13C{1H}
(acetone-d6, 298 K): δ 79.3s (C6H6), 127.2 (s, m-C (Ph)), 131.7s (o-C
(Ph)), 137s (5-C (pz)). ESI+-MS (CH3CN): m/z 701 [Ru(benzene)-
(TpmsPh)]+.
Synthesis of [Ru(cod)Cl(Tpms)] (7). [RuCl2(cod)(MeCN)2]
(0.362 g, 1.0 mmol) was dissolved in acetonitrile (20 mL), and the
solution was stirred for 30 min. Then a methanol solution (30 mL) of
Li[Tpms] (0.528 g, 1.0 mmol) was added, and the reaction mixture
was stirred at reflux for 24 h, whereafter the solvents were removed in
vacuo and the residue was redissolved in chloroform (10 mL). After
filtration to remove lithium chloride, slow evaporation yielded a yellow
crystalline powder, which was dried under vacuum and identified as
the derivative 7. It is soluble in water, alcohols, acetone, acetonitrile,
and chlorinated solvents. Yield: 0.33 g, 68%. Mp: 60 °C dec. Anal.
Calcd for C18H21ClN6O3SRu·H2O (Mw 556.00 g mol−1): C, 38.88; H,
4.17; N, 15.12; S, 5.77. Found: C, 39.36; H, 4.18; N, 15.26; S, 5.32. IR
(KBr, cm−1): 3464br ν(H2O), 3131w ν(Carom−H), 1663br δ(H2O),
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1520s ν(CN), 1239vs br, 1041s ν(SO3). H NMR (CD3OD, 298
K): δ 2.54 m, 2.69d (8H, CH2-cod), 2.85br (H2O), 4.20dbr, 4.55dbr
(4H, CH-cod), 6.42t (3H, 4-H (pz)), 7.59d (3H, 5-H (pz)), 7.92d
(3H, 3-H (pz)).
Synthesis of [Ru(cod)Cl(TpmsPh)] (8). [RuCl2(cod)(MeCN)2]
(0.362 g, 1.0 mmol) was dissolved in acetonitrile (20 mL), and the
solution was stirred for 30 min. Then a methanol solution (30 mL) of
Li[TpmsPh] (0.528 g, 1.0 mmol) was added, and the reaction mixture
stirred at reflux for 24 h, whereafter the solvents were removed in
vacuo and the residue was redissolved in chloroform (10 mL). After
filtration to remove lithium chloride, slow evaporation yielded a yellow
crystalline powder, which was dried under vacuum and identified as
the derivative 8. It is soluble in alcohols, acetone, acetonitrile, and
chlorinated solvents. Yield: 0.45 g, 59%. Mp: 134−137 °C. Anal. Calcd
for C36H33ClN6O3SRu (Mw 766.28 g mol−1): C, 56.43; H, 4.34; N,
10.97; S, 4.18. Found: C, 56.15; H, 4.26; N, 11.10; S, 4.42. IR (KBr,
cm−1): 3150w ν(Carom−H), 1532s ν(CN), 1223vs br, 1041s
H, 3.50; N, 13.22; S, 5.31. IR (KBr, cm−1): 3161w, 3123w ν(Carom
−
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H), 1521s ν(CN), 1278vs, 1098s ν(SO3), 1028vs br ν(BF4). H
NMR (CD3OD, 298 K): δ, 1.22d, 1.24d (6H, CH3−C6H4−
CH(CH3)2), 2.49s (3H, CH3−C6H4−CH(CH3)2), 3.12 m (1H,
CH3−C6H4−CH(CH3)2), 6.30dt 6.50 (4H, AA′BB′ system, CH3−
C6H4−CH(CH3)2), 6.71dd (3H, 4-H (pz)), 8.82d (3H, 3-H (pz)),
8.91d (3H, 5-H (pz)).
Synthesis of [Ru(p-cymene)(TpmsPh)]Cl (5). [RuCl(cymene)(μ-
Cl)]2 (0.306 g, 0.5 mmol) was dissolved in methanol (20 mL), the
solution was stirred for 30 min, and then Li[TpmsPh] (0.528 g, 1.0
mmol) was added. After 24 h stirring at room temperature and 24 h
stirring at reflux, a red-brown precipitate formed, which was removed
by filtration, dried under vacuum, and identified as the derivative 5. It
is soluble in chlorinated solvents. Yield: 0.59 g, 74%. Mp: 320 °C dec.
Anal. Calcd for C38H35ClN6O3SRu (Mw 792.32 g mol−1): C, 57.61; H,
4.45; N, 10.61; S, 4.05. Found: C, 57.18; H, 4.32; N, 10.34; S, 3.81. IR
(KBr, cm−1): 3124w, 3058w ν(Carom−H), 1533s ν(CN), 1232vs,
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ν(SO3). H NMR (CD3OD, 298 K): δ 2.41 m, 2.49d (8H, CH2-
cod), 3.35dbr, 3.70dbr (4H, CH-cod), 6.82d (3H, 4-H (pz)), 7.32 m
(9H, m-H and p-H (Ph)), 7.88 m (6H, o-H (Ph)), 8.13d (3H, 5-H
(pz)).
Crystals of 1, 3, and 4 suitable for X-ray diffraction were obtained
from 1/1 methanol/diethyl ether mixtures. Crystallographic data have
been deposited at the CCDC and allocated the deposition numbers
CCDC 837586−837588.
General Procedure for Catalytic Oxidation of Styrene by
H2O2. Styrene (0.25 mmol, 0.026 g) and 1 (0.0025 mmol, 0.0014 g)
were dissolved in acetone (1.5 mL). Aqueous hydrogen peroxide
[0.1214 g, 35% (w/w), 1.25 mmol] was then added in one portion,
and the reaction mixture was stirred under dinitrogen at ambient
temperature for 12 h. Then a sample (20 μL) of the resultant solution
was diluted to 1 mL and analyzed by GC-MS. Control experiments
without either the catalyst or H2O2 were performed under identical
conditions. An identical reaction procedure was performed using 5 as
catalyst.
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1042s ν(SO3). H NMR (CDCl3, 298 K): δ 1.28d, 1.35d (6H, CH3−
C6H4−CH(CH3)2), 2.15s, 2.28s (3H, CH3−C6H4−CH(CH3)2), 2.95
m, 3.08 m (1H, CH3−C6H4−CH(CH3)2), 5.29dd, 5.38d, 5.56dd,
5.62d (4H, AA′BB′ system, CH3−C6H4−CH(CH3)2), 6.55d, 6.63d
(3H, 4-H (pz)), 7.55 m (9H, m-H and p-H (Ph)), 7.88 m (6H, o-H
(Ph)), 7.96d, 8.11d (3H, 5-H (pz)). ESI+-MS (CH3CN): m/z 757
[Ru(cymene)(TpmsPh)]+.
Synthesis of [Ru(benzene)(TpmsPh)]Cl (6). [RuCl(benzene)(μ-
Cl)]2 (0.250 g, 0.5 mmol) was dissolved in methanol (20 mL) and
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dx.doi.org/10.1021/om200713v|Organometallics 2011, 30, 6180−6188