J.S.M. Samec et al. / Journal of Organometallic Chemistry 695 (2010) 1831e1837
1833
10 ꢀC)
139.0, 138.5, 130.6, 129.9, 128.8, 127.6 126.7, 125.5, 36.6, 28e30
d
323.8, 175.0, 171.5, 157.5, 150.1, 148.0, 147.6, 147.1, 146.5,
syringe; the NMR-tube was shaken upon which a color change
from green for 5 and bright yellow for 6 to yellowish and
brownish respectively was observed. The NMR-tube was heated
in an oil-bath at 50 ꢀC for 30 min. 1H NMR showed total
conversion to product [21].
overlapping signals, 27.1, 26.7. 31P NMR (121 MHz, CD2Cl2)
d 33.3.
IR (CH2Cl2)
C37H47N2O4PRu 716.2317 found 716.2335.
n
¼ 3457, 2927, 1662 cmꢁ1. FAB-HRMS: m/z calcd for
Synthesis of 5b. The same procedure as for 5a was followed,
but the reaction time was extended to 1 week or heating to
reflux over night was required. 5b was purified via column
chromatography (TSI silica) using a gradient of ethyl acetate and
MeOH to give 165 mg of 5b as a green solid in 90% yield. 1H NMR
2.2. ROMP of DCPD
6a (18.3 mg, 2.45ꢂ10ꢁ5 mol) dissolved in 1 mL of CH2Cl2 and
added all at once to a beaker with DCPD (100 g, 0.75 mol) con-
taining 6% trimer. The monomer and complex were mixed to obtain
a homogenous solution. This mixture was poured into a mold
together with HCl (0.5 mL, 1 M, 0.5 mmol) and shaken. Within 20
seconds the exotherm was reached and total polymerization was
observed. The plastic was slowly cooled to room temperature. A
heat-distortion temperature of (HDT) 130 ꢀC was observed
(expected HDT is between 125e135 ꢀC).
(300 MHz, CD2Cl2)
d
19.58 (d, J ¼ 11.5 Hz 1H), 8.36 (d, J ¼ 4.7 Hz
1H), 8.22 (m, 1H), 8.13 (m, 1H), 7.81 (m, 2H), 7.53 (m, 2H), 7.47
(m, 1H), 7.38 (m, 1H), 7.19 (m, 2H), 6.89 (m, 1H), 6.09 (m, 1H)
0.9e2.1 overlapping aliphatic signals (33H). 13C NMR (75 MHz,
CD2Cl2, 10 ꢀC)
d
314.8 (d, J ¼ 15.1 Hz), 174.2, 167.3, 157.6, 156.4,
152.0, 146.0, 138.6 (d, 11.7 Hz), 130.2, 129.5, 128.1, 128.0, 127.3,
127.1, 127.1, 126.0, 125.6. 35.3 (d, J ¼ 19.4 Hz), 31.9, 29.9, 29.1, 28.1,
27.0, 26.5. 31P NMR (121 MHz, CD2Cl2)
n
d 34.3. IR (CH2Cl2)
¼ 3457, 2925, 2847, 1633, 1599 cmꢁ1. FAB-HRMS: m/z calcd for
C37H47N2O4PRu 716.2035 found 716.2069. Anal. Calcd. for
C37H47N2O4PRu C, 62.08; H, 6.62; N, 3.91. found: C, 60.66; H, 6.27;
N, 3.41.
2.3. Influence of acid in RCM of 8
An NMR-tube equipped with a screw-cap was charged with 5 or
6 (100 mL, 0.08 mM, 0.8 mmol in CD2Cl2), 8 (19 mL, 80 mmol) and
2.1.2. Synthesis of (H2IMes)(picolinate)2Ru(CHPh) (6)
0.60 mL CD2Cl2. The NMR-tube was injected into a pre-warmed
probe at 35 ꢀC and equilibrated for 5 min. The NMR-tube is ejected
and HCl was added via syringe, the NMR-tube was shaken, t ¼ 0 was
set, and the NMR-tube was re-injected into probe. The conversion
was determined by integrating known signals of the starting
material and product [21].
A Schlenk flask was charged with (NHC)(PCy3)Cl2Ru(CHPh)
(2) (200 mg, 0.237 mmol), picolinic acid (300 mg, 2.4 mmol),
Ag2O (54 mg, 0.32 mmol) and flushed with argon. Methylene
chloride (15 mL) was canula transferred and the reaction
was stirred for 2 h at rt under argon during which time a col-
or change from red to yellow was observed. The reaction
mixture was filtered through
a glass-frit and concentrated
2.4. Trapping the 14-electron benzylidene
in vacuo. The resulting solid was purified via column chroma-
tography (TSI silica) using a gradient of ethyl acetate and MeOH
to give 6 in two different fractions (71 mg and 37 mg) as one
yellow (6a) and one green (6b) solid in 72% yield. Major isomer
An NMR-tube equipped with a screw-cap was charged with
5 or 6 (4.2 mg 5 or 4 mg 6, 5.6
enyl)benzene (10 mg, 56 mol) and 0.75 mL C6D6. HCl (100
1 M, 100 mol) was added via syringe, the NMR-tube was
shaken upon which a color change from bright yellow for 5 and
green for to brownish and yellowish respectively was
m
mol), isopropoxy-2-(prop-1-
(6a): 1H NMR (300 MHz, CD2Cl2)
d 18.57 (s,1H), 7.79 (m, 1H),
m
m
L,
m
7.73 (m, 2H), 7.38 (m, 2H), 7.34 (m, 3H), 7.01 (m, 4H), 6.79
(m, 1H), 6.65 (s, 2H), 6.36 (s, 2H), 3.94 (m, 4H), 2.44 (s, 6H),
13
2.15 (s, 6H), 2.00 (s, 6H). C NMR (75 MHz, CD2Cl2, ꢁ20 ꢀC)
6
observed. The NMR-tube was heated in an oil-bath at 50 ꢀC.
In the case of 5, 1H NMR showed total conversion to 3 after 1 h.
In the case of 6, 40% conversion to 9 was observed after 2 h.
The samples were compared to authentic samples of catalyst 3
and 9.
d
315.5, 216.0, 175.3, 172.0, 154.5, 125.1e150.4 (21 signals) 21.2,
21.0 18.5, 18.2. IR (CH2Cl2)
n
¼ 3442, 2909, 1630, 1596 cmꢁ1. FAB-
HRMS: m/z calcd for C40H40N4O4Ru 742.1925 found 742.1923.
Anal. Calcd. for C40H40N4O4Ru: C, 64.76; H, 5.43; N, 7.55. Found:
C, 63.47; H, 5.24; N, 7.03. Minor isomer (6b): in accordance to
reference [18].
2.5. Selected crystallographic details for 6a
2.1.3. Study of latency using norbornene
Red brown crystals of $6x ꢃ CH2Cl2 were obtained by diffu-
An NMR-tube equipped with a screw-cap was charged with 5b
sion of hexanes into
a saturated solution of 6x in di-
or 6a (150
0.4 mmol) and 0.6 mL C6D6. The NMR-tube was heated at 80 ꢀC for
60 min. 1H NMR revealed only starting material. HCl (10
L, 1 M,
10 mol) was added via syringe, the NMR-tube was shaken upon
mL, 2.7 mM, 0.4 mmol in C6D6), norbornene (38 mg,
chloromethane. Selected crystallographic details: size of data
crystal 0.32 ꢂ 0.17 ꢂ 0.09 mm3, formula C40H40N4O4Ru ꢃ CH2Cl2,
M ¼ 826.76 a.m.u., monoclinic space group P21/c, a ¼ 21.7076(10)
m
m
Å, b ¼ 9.5645(4) Å, c ¼ 18.0905(9) Å,
b
¼ 91.289(3)ꢀ, V ¼ 3755.0(3)
Å3, Z ¼ 4, rcalc. ¼1.462 Mg/m3. 9684 data was collected at 100(2)
which a color change from green for 5 and bright yellow for 6 to
yellowish and brownish respectively was observed. The NMR-tube
was heated in an oil-bath at 50 ꢀC for 30 min. 1H NMR showed total
conversion to product [20].
K
in the
q
-range 2.32e30.25ꢀ. Hydrogen atoms reside
on calculated positions and were refined as riding atoms.
All calculations were carried out with the SHELX program
package.[22]
2.1.4. Study of latency using diethyl diallylmalonate
3. Results and discussion
An NMR-tube equipped with a screw-cap was charged with
5b or 6a (296
m
L, 2.7 mM, 0.8
mmol in C6D6), diethyl dia-
3.1. Synthesis of complexes 5 and 6
llylmalonate (19
mL, 80 mol) and 0.45 mL C6D6. The NMR-tube
m
was heated at 80 ꢀC for 60 min. 1H NMR revealed only starting
Upon addition of 1 or 2 to a suspension of picolinic acid and
Ag2O in CH2Cl2, the corresponding 18-electron (PCy3)((kN,O)-
material. HCl (20 mL, 1 M, 20 mmol in ether) was added via