9
06
A. Leitgeb et al.
Experimental
Yield 323 mg (84 %); R
1
f
= 0.30 (cyclohexane/ethyl acetate
6
3
:1); H NMR (500 MHz, CDCl ): d = 7.50 (d, ph ), 7.39 (d,
3
3
ph ), 7.33, 7.23 (2dd, ph ), 6.98 (q, PhCHCH
4,5
Umicore M2 and Umicore M31 were received from
Umicore AG [32, 33]. Propylamine, 2-bromobenzoyl
chloride, 4-(dimethylamino)pyridine, 2,4,6-trivinylcyclo-
triboroxane–pyridine complex, and Pd(PPh3)4 were
purchased from Aldrich and were used as received.
endo,exo-Bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylic acid
dimethyl ester (6) was prepared according to literature
methods [34]. The number average molecular weights (Mn)
and polydispersity indices (PDI) were determined by gel
permeation chromatography (GPC) using THF as solvent
using the following arrangement: Merck Hitachi L6000
pump, separation columns from Polymer Standards Ser-
), 6.73 (bs,
2
trans
NH), 5.65 (d, JHH = 17.5 Hz, CHCH H), 5.28 (d,
cis
J
HH = 6.5 Hz, CHCHH ), 3.34 (m, NHCH
), 1.56 (m,
) ppm; C{ H}-NMR (125 MHz,
): d = 169.5, 135.9, 134.7, 130.2, 127.9, 127.5, 126.9,
2
1
3
1
CH
CH ), 0.92 (t, CH
2 2 3
CDCl
3
126.4, 116.8, 41.9, 23.0, 11.6 ppm.
2
(
SPY-5-31) Dichloro[j (C,O)-2-(N-propylaminocarbonyl)-
benzylidene][1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydro-
imidazol-2-ylidene]ruthenium (3, C H Cl N ORu)
M2 (280 mg, 0.3 mmol, 1 equiv.), 85 mg 2 (1.5 equiv.),
3
2
39
2 3
3
and 37 mg CuCl (1.3 equiv.) were put into 15 cm of
degassed and dry CH Cl in a glove box. The reaction
2
6
4
2
vice, 8 9 300 mm STV 5 lm grade size (10 , 10 , and
mixture was allowed to stir for 4 days, whilst light green
powder precipitated. The product was filtered and dried in
1
vacuo. Yield 125 mg (64 %); H NMR (500 MHz, DMSO-
3
0 A), a refractive index detector from Wyatt Technol-
˚
1
ogy, and an Optilab DSP interferometric refractometer.
Polystyrene standards purchased from Polymer Standard
Service were used for calibration. NMR spectra were
recorded on a Varian INOVA 500 MHz spectrometer.
6
4
d ): d = 18.99 (s, Ru=CH), 8.07 (d, ph ), 7.83 (dd, ph ),
6
5
.70 (dd, ph ), 7.21 (d, ph ), 7.07 (bs, 2H, mes), 6.76–6.54
3
7
(bs, 2H, mes), ca. 4.05 (overlapped, NCH CH N), 3.25 (m,
2
2
2
2
0
-Bromo-N-propylbenzamide (1, C H BrNO)
0 12
NHCH
2
CH
2
CH
3
), 2.36 (s, 6H, mes-CH
3
), 2.21 (bs, 6H,
1
-Bromobenzoyl chloride (500 mg, 2.2 mmol, 1 equiv.),
3
.56 cm pyridine (3 equiv.), and 14 mg DMAP (5 mol%)
mes-CH
NHCH CH
NMR (500 MHz, methanol-d
3
), 2.05–1.71 (bs, 6H, mes-CH
CH ), 0.88 (t, NHCH CH CH
): d = 19.46 (s, Ru=CH),
3
), 1.53 (m,
1
) ppm;
H
2
2
3
2
2
3
3
were dissolved in 10 cm dry, degassed CH Cl in a
2
4
2
6
4
5
3
Schlenk flask, and stirred under argon atmosphere at 0 °C.
n-Propylamine (0.21 cm , 1.1 equiv.) was added slowly.
8.06 (d, ph ), 7.88 (dd, ph ), 7.75 (dd, ph ), 7.35 (d, ph ),
0
0
5
3
3
7.13 (s, 2H, mes ), 7.10 (bs, NH), 6.61 (bs, 2H, mes ),
4.00 (bs, NCH CH N), 3.45, 3.37 (m, NHCH CH CH ),
2.44 (s, 6H, mes-CH ), 2.28 (s, 6H, mes-CH ), 2.02 (bs,
6H, mes-CH ), 1.63 (m, NHCH CH CH ), 1.02 (t,
NHCH CH CH ) ppm.
The mixture was brought to room temperature and stirred
overnight. Progress of the reaction was monitored via TLC
2
2
2
2
3
3
3
(
silica, cyclohexane/ethyl acetate = 3:1, R = 0.22). For
f
3
2
2
3
workup, the solution was washed with HCl and NaHCO3.
The organic extract was dried with Na SO . Removing the
2
2
3
2
4
2
(SPY-5-34) Dichloro[j (C,O)-2-(N-propylaminocarbonyl)-
solvent in vacuo yielded a light yellow solid which was
benzylidene][1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydro-
imidazol-2-ylidene]ruthenium (4, C H Cl N ORu)
then purified by column chromatography (SiO , cyclohex-
2
3
2
39
2 3
ane/ethyl acetate = 3:1). Yield 386 mg (72 %); R = 0.22
f
M31 (100 mg, 0.13 mmol, 1 equiv.) and 38 mg 2
(
1
cyclohexane/ethyl acetate = 3:1); H NMR (500 MHz,
(
3
1.5 equiv.) were dissolved in 4 cm of degassed CHCl
6
3
3
CDCl ): d = 7.56 (d, ph ), 7.50 (d, ph ), 7.34, 7.25 (2dd,
ph ), 6.03 (bs, NH), 3.41 (m, NHCH ), 1.65 (m,
2
1
CH CH ), 0.99 (t, CH ) ppm; C{ H}-NMR (125 MHz,
3
in a Schlenk tube. The reaction mixture was allowed to stir
at room temperature for 18 h. During this time the color
turned from brownish red to deep green. The solvent was
removed by evacuation. The residual solid was washed
with n-pentane. At this stage an NMR of the residue in
4,5
3
1
2
2
3
CDCl ): d = 170.1, 138.4, 133.0, 130.6, 128.1, 127.9,
3
1
19.2, 41.8, 23.0, 11.6 ppm.
N-Propyl-2-vinylbenzamide (2, C H NO)
1
CDCl
3
was performed and allowed the observation of
Cl solution
2 15
2-Bromo-N-propylbenzamide (386 mg, 1.6 mmol, 1 equiv.),
462 mg vinylboronic anhydride–pyridine complex (1.2
4ꢀpy. Ether diffusion into a concentrated CH
2
2
of 4ꢀpy, carried out under argon atmosphere, furnished
emerald green crystals of 4. Yield 53 mg (60 %). TLC:
equiv.), and 662 mg K CO (3 equiv.) were dissolved in a
2
3
3
mixture of 6 cm degassed DME and 2 cm H O in a Schlenk
3
greenish trace up to
R
= 0.51 (silica, CH
Cl /
2 2
2
f
flask, heated to reflux (90 °C), and stirred under argon
MeOH = 20:1).
1
atmosphere. Pd(PPh ) (55 mg, 3 mol%) was added. The
4ꢀpy: H NMR (500 MHz, CDCl
3
): d = 17.73 (s,
Ru=CH), 8.91 (bs, 1H, ph), 8.41 (d, 2H, py ), 8.27 (bs,
3
4
3
mixture was refluxed overnight. Water (10 cm ) was added
2,6
4
1H, ph), 7.78 (bs, 1H, mes), 7.74 (dd, py ), 7.52 (dd, 1H,
and the solution was then filtered and extracted with Et O.
2
3
,5
AfterdryingwithNa SO , theorganicsolventwasremovedin
2
ph), 7.22 (dd, 2H, py ), 7.40 (d, 1H, ph), ca. 7.05
(overlapped, bs, 1H mes), ca. 6.45 (bs, 2H, mes), ca. 4.03
4
vacuo. Purification via column chromatography (SiO2,
cyclohexane/ethyl acetate = 3:1) yielded a light yellowsolid.
(bs, NCH CH N), 3.57–3.51 (m, NHCHH), ca. 2.60–1.61
2 2
1
23