P. Nieczypor et al. / Journal of Organometallic Chemistry 625 (2001) 58–66
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4.1.2. Data for 4a
4.2.2. Ru(ꢀCHPh)Cl2(dppf ) (3)
Starting from 2.02 ml (10.1 mmol) of dicyclo-
hexylphosphine and 1,5-dibromopentane (0.68 ml, 0.50
mmol), a white solid was obtained with a yield of 65%
(1.36 g). 1H-NMR (C6D6): l (ppm) 2.05–1.10 (m).
13C{1H}-NMR (C6D6): l (ppm) 34.31 (d, J=14.6 Hz),
31.18 (d, J=14.6 Hz), 29.77 (d, J=8.5 Hz), 29.21 (d,
J=19.6 Hz), 28.08 (pseudo t, Japp=3.8 Hz), 27.32 (s),
22.25 (d, J=18.3 Hz); 31P{1H}-NMR (C6D6): l (ppm)
−4.82 (s). FAB-MS: m/z (rel. intensity,%): 465 ([M+
H]+, 85), 464 ([M]+, 10), 463 ([M−H]+, 45), 381
([M−Cy]+, 100), 299 ([M−2Cy+H]+, 30), 267 (88),
153 (15), 83 (35), 81 (25), 41 (15). Anal. Calc. for
C29H54P2: C, 74.96; H, 11.71. Found: C, 74.69; H,
11.78%.
To a cooled −78°C solution of 1a (0.235 g, 0.30
mmol) in CH2Cl2 (30 ml), a solution of dppf (0.166 g,
0.30 mmol) in CH2Cl2 (5 ml) was added via a syringe.
The reaction mixture was stirred for 20 min at −78°C.
It was allowed to warm to r.t., and the colour of the
mixture changed to brown. After 1 h most of the
solvent was evaporated and a greenish solid was precip-
itated with pentane (25 ml). The orange solution was
discarded and the solid was washed a few times with
pentane, reprecipitated twice from CH2Cl2 and then
dried under vacuum. 0.123 g (50%) of a green–brown
microcrystalline product was obtained. 1H-NMR
(CD2Cl2): l (ppm) 17.20 (t, JPH=18.3 Hz; 1H,
RuꢀCHPh); 8.66 (d, JHH=7.7 Hz; 2H, o-CHarom);
7.92–6.95 (m, 23H, CHarom); 4.78, 4.60, 4.48, 4.37
(4×s, 4×2H, CH of Cp). 13C{1H}-NMR (CD2Cl2): l
(ppm) 303.06 (t, J=17.4 Hz, RuꢀCHPh), 151.06,
136.21 (t, J=5.1 Hz) 133.70 (t, J=4.9 Hz), 133.38,
131.40 (2C), 130.03 (2C), 128.39 (t, J=4.9 Hz), 127.75
(t, J=5.2 Hz), 75.16 (4C), 73.33 (2C, t, J=3.6 Hz),
70.14 (2C). 31P{1H}-NMR (CD2Cl2): l (ppm) 51.95 (s).
IR (KBr): (cm−1) 3054 (m), 1482 (m), 1434 (s), 1249
(m), 1178 (m), 1161 (m), 1094 (s), 1038 (m), 874 (w),
826 (w), 744 (s), 693 (s), 631 (w), 562 (m), 511 (s), 476
(m). FD-MS: m/z (rel. intensity,%): 816 ([M]+, 100),
780 (20), 726 (5), 689 (5), 586 (10), 554 (8); isotopic
pattern for [C41H34Cl2FeP2Ru]+: m/z (Calc. intensity,
Found intensity): 808 (1, 2), 809 (0.5, 1), 810 (10, 18),
811 (6, 14), 812 (13, 15), 813 (31, 32), 814 (43, 45), 815
(63, 75), 816 (100, 100), 817 (63, 67), 818 (92, 92), 819
(41, 51), 820 (38, 41), 821 (14, 23), 822 (7, 12), 823 (2,
4). Anal. Calc. for C41H34Cl2FeP2Ru×CH2Cl2: C,
55.98; H, 4.08. Found: C, 55.96; H, 4.02%.
4.2. Synthesis of ruthenium carbene complexes bearing
diphosphines
4.2.1. Ru(ꢀCHPh)Cl2(xantphos) (2)
Complex 1a (0.256 g, 0.325 mmol) was dissolved in
CH2Cl2 (20 ml) and the solution was cooled down to
−78°C. The xantphos ligand (0.171 g, 0.295 mmol)
was added as a solution in CH2Cl2 (5 ml) via a syringe.
The reaction mixture was stirred for 15 min at −78°C,
then allowed to warm to r.t. and stirred for 2 h. The
mixture was then concentrated and a green precipitate
was formed upon addition of pentane (20 ml). The
brownish liquor was discarded and the solid was
washed with pentane. It was redissolved in CH2Cl2 and
reprecipitated. The reaction yielded 0.23 g (92%) of a
green microcrystalline solid. 1H-NMR (CD2Cl2): l
(ppm) 19.08 (t, JPH=7.5 Hz; 1H, RuꢀCHPh); 7.92 (d,
J
HH=7.6 Hz; 2H, CH of xanthene); 7.78 (d, JHH=7.5
Hz; 2H, CH of xanthene); 7.59−7.23 (m, 25 H, 5×
Ph); 7.08 (t, JHH=7.5 Hz; 2H, CH of xanthene); 1.82
(s, 6H, CH3). 13C{1H}-NMR (CD2Cl2): l (ppm) 320.59
(t, J=10.6 Hz, RuꢀCHPh), 155.62 (t, J=4.0 Hz),
154.39 (t, J=7.3 Hz), 135.45, 134.91 (t, J=5.5 Hz),
132.68, 131.41 (d, J=45 Hz), 131.18 (d, J=46 Hz),
131.09 (d, J=47 Hz), 130.22, 129.17, 128.02 (t, J=4.9
Hz), 125.37, 123.31 (t, J=18.9 Hz), 35.19 (C(CH3)2),
33.52 (CH3). 31P{1H}-NMR (CD2Cl2): l (ppm) 36.26
(s). IR (KBr): (cm−1) 3056 (m), 2953 (w), 2918 (w),
1481 (w), 1436 (s), 1399 (vs), 1260 (w), 1213 (m), 1194
(m), 1094 (m), 877 (w), 743 (m), 693 (s), 522 (s), 505
(m). FD-MS: m/z (rel. intensity,%): 840 ([M]+, 100),
820 (15), 611 (5), 353 (97); isotopic pattern for
[C46H38Cl2OP2Ru]+: m/z (Calc. intensity, Found inten-
sity): 834 (10, 20), 835 (5, 12), 836 (11, 24), 837 (28, 44),
838 (39, 59), 839 (62, 80), 840 (100, 100), 841 (66, 82),
842 (96, 95), 843 (45, 63), 844 (40, 61), 845 (16, 28), 846
(7, 28), 847 (2, 17), 848 (1, 6). Anal. Calc. for
C46H38Cl2OP2Ru: C, 65.71; H, 4.56. Found: C, 64.92;
H, 4.69%.
4.2.3. Cl2(PhHCꢀ)Ru[v-(Cy2P(CH2)8PCy2)]2Ru-
(ꢀCHPh)Cl2 (5b)
RuCl2(PPh3)3 (1.44 g, 1.50 mmol) was dissolved in
CH2Cl2 (50 ml) and the solution was cooled to −50°C.
The cooled to 0°C solution of phenyldiazomethane
(ꢀ2 molar excess) was added via a polyethylene can-
nula over 10 min. Then the mixture was allowed to
warm up to −30°C and then 1.1 molar excess (0.88 g)
of diphosphine 4b was added. The reaction mixture was
allowed to warm up to r.t. and stirred for the next 30
min. Next, most of the solvent was evaporated leaving
a dark-red oil. Ethanol (30 ml) was added and the
mixture was vigorously stirred. A dark-red precipitate
was formed, which was separated from the liquor,
redissolved and reprecipitated with ethanol. The red–
pink solid thus obtained was washed with cooled
CH2Cl2 (10 ml) and dried, giving a pink solid. The
remaining liquor was concentrated to a few millilitres
and left overnight at −20°C. The crystallised dark-
pink solid was filtered, washed with cold CH2Cl2 and
dried. The yield of the product was 0.392 g (34%).