4344 Organometallics, Vol. 29, No. 19, 2010
Peeck et al.
7.45 (s, 4H, m-Haryl), 4.83 (s, 4H, C5H4), 4.51 (s, 4H, NCH2CH2N),
C
NMR (75 MHz, CDCl3): δ 160.6, 141.5, 135.9, 131.4, 126.5, 83.6,
69.8, 69.7, 67.0, 51.3, 17.8. HRMS: m/z calcd for C39H39N2Fe2
647.18120; found 647.18014.
HCl solution in dioxane (4 M, 0.134 mmol) was added and the
reaction mixture stirred for 15 min. The light green precipitate
was filtrated, washed with pentane (3 ꢀ 10 mL), and dried
4.40 (s, 4H, C5H4), 4.07 (s, 10H, C5H5), 2.43 (s, 12H, o-CH3). 13
1
in vacuo. Yield: 49 mg (98%). H NMR (CD3OD, 500 MHz):
δ 16.87 (s, 1H, RuCH), 7.62 (m, 1H, Hbenzylidene), 7.49 (bs, 1H,
m-Haryl), 7.05 (d, J=8.5 Hz, 1H, Hbenzylidene), 7.03 (dd, J=7.7,
1.4 Hz, 1H, Hbenzylidene), 6.93 (t, J=7.4 Hz, 1H, Hbenzylidene), 5.03
(sept, J=6.1 Hz, 1H, OCH(CH3)2), 4.24 (s, 4H, NCH2CH2N),
3.70 (bs, 8 H, N(CH2CH3)2), 2.62 (bs, 12 H, o-CH3), 1.34 (d, J=
6.1 Hz, 6H, OCH(CH3)2), 1.28 (t, J = 7.1 Hz, 12H, N(CH2-
CH3)2). 13C NMR (CD3OD, 126 MHz): δ 293.3, 211.4, 153.9,
146.3, 143.8, 131.6, 123.8, 123.5, 123.1, 114.7, 76.6, 54.5, 53.1,
22.2, 22.1, 11.2.
Complex 5d. N,N0-Bis(2,6-dimethyl-4-ferrocenylphenyl)imidazo-
linium chloride (4d) (350 mg, 0.51 mmol) and KOtBu (57 mg,
0.51 mmol) were weighed in a Schlenk flask under an atmosphere
of argon. Dried and degassed toluene (20 mL) was added and
the mixture stirred for 15 min. Next dichlorobenzylidenebis-
(tricyclohexylphosphine)ruthenium(II) (210 mg, 0.26 mmol)
was added. The mixture was stirred at 50 °C for 1 h, and the
volatiles were evaporated in vacuo. The remaining solid was
purified by column chromatography (cyclohexane/ethyl acet-
ate, 15:1 v/v) and the desired product obtained as a brown solid.
Complex 7a. Complex 5a (200 mg, 0.21 mmol) was dissolved
in dried and degassed pyridine (2 mL). After 5 min the resulting
green solution was transferred into cold pentane (10 mL) and the
green precipitate was filtered and dried in vacuo. Yield: 120 mg
1
Yield: 111 mg (36%). H NMR (CDCl3, 500 MHz): δ 19.09
(s, 1H, RudCH), 8.00-5.60 (m, 6H, m-Haryl þ Hbenzylidene), 7.28
(s, 2H, m-Haryl), 7.21 (t, J=7.3 Hz, 1H, Hbenzylidene), 4.62 (“t”,
J=1.7 Hz, 4H, C5H4), 4.36 (bs, 2H, C5H4), 4.31(“t”, J=1.7 Hz,
2H, C5H4), 4.27 (“t”, J=1.7, 2H, C5H4), 4.11 (s, 5H, C5H5),
4.10-4.04 (m, 2H, NCH2CH2N), 4.01 (s, 5H, C5H5), 4.00-3.86
(m, 2H, NCH2CH2N), 2.74 (bs, 6H, o-CH3), 2.50-2.20 (m, 6H,
o-CH3), 2.14 (q, J=11.0 Hz, 3H, PCH), 1.58-1.19 (m, 15H, Cy),
1.12-0.69 (m, 15H, Cy). 13C NMR (CDCl3, 126 MHz): δ 295.1,
220.7 (d, JC-P=78 Hz), 151.5, 139.8, 139.0, 138.9, 137.8, 137.0,
135.7, 128.1, 128.0, 126.9, 126.3, 85.5, 85.1, 69.7, 69.5, 68.9, 68.6,
1
(68%). H NMR (500 MHz, CDCl3): δ 19.25 (s, 1H, RuCH),
8.64 (s, 2H, Hpyridine), 7.85 (s, 2H, Hpyridine), 7.75 (d, J=7.6 Hz,
2H, Hbenzylidene), 7.63 (s, 2H, Hpyridine), 7.43 (t, J=7.3 Hz, 1H,
Hbenzylidene þ s, 1H, Hpyridine), 7.24 (s, 1H, Hpyridine), 7.03 (t, J=
7.7 Hz, 2H, Hbenzylidene), 6.91 (s, 2H, Hpyridine), 6.47 (s, 2H,
m-Haryl), 6.21 (s, 2H, m-Haryl), 4.30-3.90 (m, 4H, NCH2CH2N),
3.36 (m, 8H, NCH2CH3), 2.60 (s, 6H, o-CH3), 2.21 (s, 6H,
o-CH3), 1.19 (m, 12H, NCH2CH3). 13C NMR (126 MHz, CDCl3):
δ 312.8, 218.9, 152.1, 151.5, 150.0, 147.9, 147.4, 141.3, 138.5,
136.4, 135.9, 130.3, 129.6, 127.9, 124.9, 123.7, 111.1, 110.9, 52.3,
51.0, 44.3 (two signals), 21.3, 19.1, 12.9 (two signals). Decom-
position upon attempted mass spectrometric characterization.
Complex 7c. Complex 5c (200 mg, 0.20 mmol) was dissolved
in dried and degassed pyridine (2 mL). After 5 min the resulting
green solution was transferred into cold pentane (10 mL), and
the green precipitate was filtered and dried in vaccuo. Yield:
66.8, 52.3, 51.4, 31.6 (d, JC-P =16 Hz), 29.1, 27.7 (d, JC-P
=
10 Hz), 26.3, 20.3, 19.0. 31P NMR (CDCl3, 81 MHz): δ 28.27.
MS (ESI): m/z 1153.6 (M - Cl), 647.5 (M - Cl2RuCHPhPCy3).
Complex 6d. Grubbs second-generation complex 5d (111 mg,
0.090 mmol) was placed in a Schlenk flask and dissolved in dried
and degassed toluene (20 mL). CuCl (28 mg, 0.28 mmol) and
isopropoxystyrene (35 μL, 0.19 mmol) were added, and the
mixture was stirred for 2 h at 40 °C. The volatiles were removed
in vacuo, and the residue was purified by column chromato-
graphy (cyclohexane/ethyl acetate, 6:1 v/v). The Hoveyda-type
complex 6d was obtained as a green crystalline solid. Yield: 72 mg
1
130 mg (73%). H NMR (500 MHz, CDCl3): δ 19.23 (s, 1H,
RuCH), 8.71 (s, 4H, Hpyridine), 7.96 (s, 2H, Hpyridine), 7.76 (d, J=
7.7 Hz, 2H, Hbenzylidene), 7.61 (s, 1H, Hpyridine), 7.44 (t, J=7.4 Hz,
1H, Hbenzylidene), 7.31 (s, 1H, Hpyridine), 7.17 (s, 2H, m-Haryl), 7.10
(m, J = 2H, Hbenzylidene), 7.08 (s, 2H, m-Haryl), 6.81 (s, 2H,
1
(80%). H NMR (CDCl3, 500 MHz): δ 16.81 (s, 1H, RuCH),
7.44 (t, J=7.4 Hz, 1H, Hbenzylidene), 7.35 (s, 4H, m-Haryl), 7.02
(dd, J = 7.9, 1.6 Hz, 1H, Hbenzylidene), 6.85-6.78 (m, 2H,
Hbenzylidene), 4.91 (sept., J=6.2 Hz, 1H, (CH3)2CHOAr), 4.67
(s, 4H, C5H4), 4.36 (s, 4H, C5H4), 4.19 (s, 4H, NCH2CH2N),
4.14 (s, 10H, C5H5), 2.55 (bs, 12 H, o-CH3), 1.35 (d, J=6.2 Hz,
6H, (CH3)2CHOAr). 13C NMR (CDCl3, 126 MHz): δ 296.5,
211.7, 152.4, 145.4, 140.4, 139.4, 139.3, 129.7, 126.8, 123.0,
122.4, 113.0, 85.3, 75.1, 69.8, 69.1, 66.9, 51.7, 21.5, 19.4. MS
(ESI): m/z: 966.1 (M), 931.1(M - Cl), 895.3 (M - 2 Cl), 853.5
(M - 2 Cl - C3H7).
Complex 6a. Grubbs second-generation complex 5a (99 mg,
0.10 mmol) was placed in a Schlenk flask and dissolved in dry
and degassed toluene (20 mL). CuCl (31 mg, 0.31 mmol) and
isopropoxystyrene (34 mL, 0.21 mmol) were added, and the
mixture was stirred for 1 h at 40 °C. The volatiles were removed
in vacuo and the residue purified by column chromatography
(cyclohexane/ethyl acetate, 2:1 v/v). The Hoveyda-type complex
6a was obtained as a green crystalline solid. Yield: 55 mg (73%).
1H NMR (500 MHz, CDCl3): δ 16.86 (s, 1H, RudCH), 7.46 (td,
J=8.0, 1.6 Hz, 1H, Hbenzylidene), 7.03 (dd, J=7.5, 1.6 Hz, 1H,
H
pyridine), 4.00 (s, 4H, NCH2CH2N), 2.10-2.90 (bs, 12H,
o-CH3). 13C NMR (126 MHz, CDCl3): δ 315.4, 219.4, 151.9,
150.0, 141.0 (bs),136.4, 135.8, 131.6, 130.5, 130.3, 128.2, 123.7,
51.5, 19.5 (bs). Decomposition upon attempted mass spectro-
metric characterization.
Complex 8d. [Ir(μ-Cl)(cod)]2 (50 mg, 0.08 mmol) and KOtBu
(17 mg, 0.15 mmol) were placed in a Schlenk tube, dissolved in
thf (5 mL) under an atmosphere of Ar, and stirred for 10 min at
room temperature. To this mixture was added N,N0-bis(2,6-
dimethyl-4-ferrocenylphenyl)imidazolinium chloride (4d) (93 mg,
0.14 mmol). The reaction mixture was stirred for 2 h at room
temperature, the volatiles were evaporated in vacuo, and the
residue was purified by column chromatography (cyclohexane/
ethyl acetate (10:1 v/v)). The product was obtained as an orange
solid. Yield: 97 mg (66%). 1H NMR (CDCl3, 500 MHz): δ 7.25
(s, 4H, m-Haryl), 4.67 (“t”, J=1.7 Hz, 4H, C5H4), 4.33 (“t”, J=
1.7 Hz, 4H, C5H4), 4.18-4.14 (m, 2H, CHCOD), 4.07 (s, 10H,
C5H5), 3.96 (s, 4H, NCH2CH2N), 3.20-3.17 (m, 2H CHCOD),
2.63 (s, 6H, o-CH3), 2.42 (s, 6H, o-CH3), 1.72-1.68 (m, 4H,
CH2COD), 1.34-1.30 (m, 4H, CH2COD). 13C NMR (CDCl3, 126
MHz): δ 207.4, 139.1, 138.3, 136.6, 135.4, 126.6, 125.1, 84.5,
83.9, 69.7, 69.2, 66.8, 66.3, 51.6, 51.4, 33.7, 28.8, 20.1, 18.7. MS
(EI): m/z 944 (M -C3H2), 918 (M - cp), 874 (M - cod).
Complex 9d. Complex 8d (66 mg, 0.07 mmol) was dissolved in
CH2Cl2 (20 mL) and CO bubbled through this solution for
15 min. The volatiles were evaporated, and the residue was
washed with pentane (3 ꢀ 5 mL) and dried in vacuo. The product
was obtained as an orange solid. Yield: 60 mg (96%). 1H NMR
(CDCl3, 500 MHz): δ 7.24 (s, 4H, m-Haryl), 4.64 (“t”, J=1.8 Hz,
4H, C5H4), 4.32 (“t”, J = 1.8 Hz, 4H, C5H4), 4.09 (s, 4H,
NCH2CH2N), 4.07 (s, 10H, C5H5), 2.50 (s, 12H, o-CH3). 13C
NMR (CDCl3, 126 MHz): δ 202.0, 180.1, 168.7, 140.0, 136.0,
H
benzylidene), 6.84 (t, J = 7.5 Hz, 1H, Hbenzylidene), 6.79 (d, J =
8.2 Hz, 1H, Hbenzylidene), 6.52 (s, 4H, m-Haryl), 4.90 (sept., J=
6.1 Hz, 1H, OCH(CH3)2), 4.14 (s, 4H, NCH2CH2N), 3.42 (bs,
8H, N(CH2CH3)2), 2.57 (bs, 6H, o-CH3), 2.35 (bs, 6H, o-CH3),
1.31 (d, 6 H, J=6.1 Hz, OCH(CH3)2, 1.23 (bs, 12H, N(CH2-
CH3)2). 13C NMR (126 MHz, CDCl3): δ 299.3, 211.8, 152.3,
147.9, 147.8, 145.7, 141.3, 139.1, 129.3, 128.9, 124.7, 122.9,
122.3, 113.0, 111.5, 111.0, 74.9, 52.6, 51.3, 44.5, 21.3, 19.1,
12.8. HRMS: m/z calcd for C37H52N4OCl2Ru 740.25530; found
740.25740.
Complex 6a 2HCl. Complex 6a (50 mg, 0.067 mmol) was
3
dissolved in dried and degassed toluene (20 mL). Then 34 μL of a