[RuCp(PR3)(CH3CN)2]PF6 (R = Ph, Me, Cy). Convenient Precursors for Mixed Ruthenium(II) and Ruthenium(IV) Half-Sandwich Complexes

Article abstract of DOI:10.1021/om990245o

The reaction of [RuCp(CH₃CN)₃]PF₆ (1) with the monodentate ligands PR₃ (R = Me, Ph, Cy) affords the cationic complexes [RuCp(PR₃)(CH₃CN)₂]PF₆ (2a-c) in high yields. The CH₃-CN exchange kinetics has been studied by NMR, suggesting a dissociative mechanism. Due to van der Waals repulsive interactions between PCy₃ and the nitrile ligands, CH₃CN is particularly labile in 2c. The chemistry of 2a-c has been further investigated with respect to substitution and oxidative addition.

Full text of DOI:10.1021/om990245o

Organometallics 1999, 18, 3843-3850
3843
[Ru Cp (P R3)(CH3CN)2]P F 6 (R ) P h , Me, Cy). Con ven ien t
P r ecu r sor s for Mixed Ru th en iu m (II) a n d Ru th en iu m (IV)
Ha lf-Sa n d w ich Com p lexes
Eva Ru¨ba,† Walter Simanko,† Klaus Mauthner,† Kamran M. Soldouzi,†
Christian Slugovc,† Kurt Mereiter,‡ Roland Schmid,† and Karl Kirchner*,†
Institute of Inorganic Chemistry and Institute of Mineralogy, Crystallography, and Structural
Chemistry, Technical University of Vienna, Getreidemarkt 9, A-1060 Vienna, Austria
Received April 7, 1999
The reaction of [RuCp(CH3CN)3]PF6 (1) with the monodentate ligands PR3 (R ) Me, Ph,
Cy) affords the cationic complexes [RuCp(PR3)(CH3CN)2]PF6 (2a -c) in high yields. The CH3-
CN exchange kinetics has been studied by NMR, suggesting a dissociative mechanism. Due
to van der Waals repulsive interactions between PCy3 and the nitrile ligands, CH3CN is
particularly labile in 2c. The chemistry of 2a -c has been further investigated with respect
to substitution and oxidative addition.
In tr od u ction
(CH3CN)2]+, [RuCp(P(OMe)3)2(CH3CN)]+, and [RuCp-
(P(OMe)3)3]+ is obtainable.2 Recently, 1 has been
converted to [RuCp(η1(P)-2-(PPh2){C6H4CH2(OR)2})(CH3-
CN)2]CF3SO3 (R ) Me, Et).11 Thus, 1 might be a suitable
starting material for providing mixed half-sandwich
complexes of the type [RuCp(L)(L′)(L′′)]+. In the present
paper we report the synthesis, structure, and exchange
kinetics of [RuCp(L)(CH3CN)2]+ (L ) PPh3, PMe3, PCy3).
In addition, the synthesis of a range of mixed Ru(II) and
Ru(IV) half-sandwich complexes derived therefrom is
described.
The chemistry of cyclopentadienylruthenium com-
plexes has been based largely on the precursors RuCp-
(PPh3)2Cl and RuCp(CO)2Cl.1 However, the selective
replacement of either PPh3 or CO turned out to be very
difficult, limiting the synthetic utility with respect to
the introduction of reactive and thermally sensitive
ligand systems. Therefore, more labile systems, includ-
ing [RuCp(CH3CN)3]+ (1),2 RuCp(COD)Cl (COD ) 1,5-
cyclooctadiene),3 and RuCp(PPh3)(η2(O,O)-CH3COO),4
have been developed, making available the respective
pseudo coordinatively unsaturated species [RuCp]+,5-7
RuCpCl,3,8,9 and [RuCp(PPh3)]+ 10 under mild condi-
tions. These intermediates react with potential, mostly
chelating, ligands to give a variety of neutral and
cationic cyclopentadienylruthenium(II) complexes.
Of the above complexes, we find the cationic complex
1 most promising for further study, since the CH3CN
ligands can be replaced in a controlled and stepwise
fashion. Thus, using monodentate P(OMe)3 under vari-
ous conditions, any mixed complex [RuCp(P(OMe)3)-
Exp er im en ta l Section
Gen er a l In for m a tion . All manipulations were performed
under an inert atmosphere of argon by using Schlenk tech-
niques. All chemicals were standard reagent grade and used
without further purification. The solvents were purified ac-
cording to standard procedures.12 The deuterated solvents were
purchased from Aldrich and dried over 4 Å molecular sieves.
TLC was performed on Riedel-deHaen silica gel 60 F 254 TLC
sheets (layer thickness 0.2 mm). For column chromatography,
silica gel grade 60 (70-230 mesh, 60 Å), purchased from
Merck, or neutral MN-aluminum oxide, purchased from
Macherey-Nagel, was used. [RuCp(CH3CN)3]PF6 (1) and was
prepared according to the literature procedure.2 1H, 13C{1H},
and 31P{1H} NMR spectra were recorded on a Bruker AC-250
spectrometer operating at 250.13, 62.86, and 101.26 MHz,
respectively, and were referenced to SiMe4 and H3PO4 (85%).
Infrared spectra were recorded on a Perkin-Elmer 16PC FTIR
spectrometer. Microanalyses were done by the Microanalytical
Laboratories at the University of Vienna.
[Ru Cp (P P h 3)(CH3CN)2]P F 6 (2a ). To a solution of 1 (247
mg, 0.568 mmol) in CH2Cl2 (8 mL) was added PPh3 (149 mg,
0.568 mmol), and the mixture was stirred for 2 h at room
temperature. After removal of the solvent, a yellow powder
was obtained, which was collected on a glass frit, washed with
Et2O (3 × 5 mL), and dried under vacuum. Yield: 350 mg
(94%). Anal. Calcd for C27H26F6N2P2Ru: C, 49.47; H, 4.00; N,
4.27. Found: C, 49.56; H, 3.97; N, 4.13. 1H NMR (δ, CDCl3,
* To whom correspondence should be addressed. E-mail: kkirch@
mail.zserv.tuwien.ac.at.
† Institute of Inorganic Chemistry.
‡ Institute of Mineralogy, Crystallography, and Structural Chem-
istry.
(1) Bennett, M. A.; Bruce, M. I.; Matheson, T. W. In Comprehensive
Organometallic Chemistry; Wilkinson, G., Ed.; Pergamon: Oxford,
U.K., 1982; Vol. 4, pp 775-796.
(2) Gill, T. P.; Mann, K. R. Organometallics 1982, 1, 485.
(3) (a) Albers, M. O.; Robinson, D. J .; Shaver, A.; Singleton, E.
Organometallics 1986, 5, 2199. (b) Kirchner, K.; Mereiter, K.; Um-
fahrer, A.; Schmid, R. Organometallics 1994, 13, 1886.
(4) Daniel, T.; Mahr, N.; Barun, T.; Werner, H. Organometallics
1993, 12, 1475.
(5) Simanko, W.; Tesch, W.; Sapunov, V. N.; Schmid, R.; Kirchner,
K.; Coddington, J .; Wherland, S. Organometallics 1998, 17, 5674.
(6) Slugovc, C.; Mereiter, K.; Schmid, R.; Kirchner, K. Organome-
tallics 1999, 18, 1011.
(7) McNair, A. M.; Mann, K. R. Inorg. Chem. 1986, 25, 2519.
(8) Albers, M. O.; Liles, D. C.; Robinson, D. J .; Shaver, A.; Singleton,
E. Organometallics 1987, 6, 2347.
(9) Kirchner, K.; Mereiter, K.; Umfahrer, A.; Schmid, R. Organo-
metallics 1994, 13, 1886.
(10) Braun, T.; Gevert, O.; Werner, H. J . Am. Chem. Soc. 1995, 117,
7291.
(11) Grotjahn, D. B.; Lo, H. C. Organometallics 1996, 15, 2860.
(12) Perrin, D. D.; Armarego, W. L. F. Purification of Laboratory
Chemicals, 3rd ed.; Pergamon: New York, 1988.
10.1021/om990245o CCC: $18.00 © 1999 American Chemical Society
Publication on Web 09/13/1999

3844 Organometallics, Vol. 18, No. 19, 1999
Ru¨ba et al.
20 °C): 7.47-7.28 (m, 15H, Ph), 4.43 (s, 5H, Cp), 2.12 (d,
J HP ) 1.1 Hz, 6H, CH3). 13C{1H} NMR (δ, CDCl3, 20 °C): 133.7
Anal. Calcd for C12H20F6P2Ru: C, 32.66; H, 4.57. Found: C,
33.01; H, 4.88. 1H NMR (δ, acetone-d6, 20 °C): 5.74 (m, 2H,
2
1
(d, J CP ) 11.1 Hz, 6C, Ph2,6), 133.6 (d, J CP ) 42.5 Hz, 3C,
Ph1), 130.5 (3C, Ph4), 128.8 (d, 3J CP ) 9.7 Hz, 6C, Ph3,5), 127.7
(2C, NtC), 77.1 (5C, Cp), 3.8 (2C, CH3). 31P{1H} NMR (δ,
CDCl3, 20 °C): 51.7 (PPh3), -143.5 (1J PF ) 712.3 Hz, PF6). IR
(KBr, cm-1): 2285 (m, νCN).
3
3
CH2dCH), 5.41 (d, J HP ) 0.9 Hz, 5H, Cp), 3.12 (m, J HHcis
)
2
7.2 Hz, 2H, CH2dCH), 1.88 (d, J HP ) 10.2 Hz, 9H, PMe3),
0.25 (m, 3J HHtrans ) 9.7 Hz, 3J HP ) 14.6 Hz, 2H, CH2dCH). 13C-
{1H} NMR (δ, acetone-d6, 20 °C): 84.7 (5C, Cp), 80.9 (d,
2J CP ) 2.2 Hz, 2C, CH2dCH), 43.3 (d, 2J CP ) 4.9 Hz, 2C, CH2d
1
[Ru Cp (P Me3)(CH3CN)2]P F 6 (2b). This complex has been
prepared analogously to 2a with 1 (100 mg, 0.230 mmol) and
PMe3 (24 µL, 0.230 mmol) as the starting materials. Yield: 100
mg (93%). Anal. Calcd for C12H20F6N2P2Ru: C, 30.71; H, 4.30;
CH), 19.8 (d, J CP ) 37.2 Hz, 3C, PMe3). 31P{1H} NMR (δ,
acetone-d6, 20 °C): 13.6 (PMe3), -142.7 (1J PF ) 707.6 Hz, PF6).
[Ru Cp (η4-CH2dC(Me)CHdCH2)(P Me3)]P F 6 (3d ). To a
solution of 2b (110 mg, 0.234 mmol) in acetone (3 mL) was
added isoprene (100 µL, 1 mmol), and the mixture was stirred
for 2 h at room temperature. After removal of the solvent, a
bright powder was obtained, which was collected on a glass
frit, washed with Et2O (3 × 5 mL), and dried under vacuum.
Yield: 90 mg (84%). Anal. Calcd for C13H22F6P2Ru: C, 34.29;
1
N, 5.97. Found: C, 30.88; H, 4.46; N, 5.86. H NMR (δ, CD3-
NO2, 20 °C): 4.52 (s, 5H, Cp), 2.38 (d, J HP ) 1.6 Hz, 6H, CH3),
2
1.54 (d, J HP ) 9.8 Hz, 9H, PMe3). 13C{1H} NMR (δ, CD3NO2,
20 °C): 128.1 (2C, NtC), 76.0 (d, J CP ) 2.3 Hz, 5C, Cp), 18.0
2
(d, J CP ) 28.7 Hz, 3C, P(CH3)3), 3.7 (d, J CP ) 1.0 Hz, CH3).
31P{1H} NMR (δ, CD3NO2, 20 °C): 5.4 (PMe3), -145.9 (1J PF
)
1
H, 4.87. Found: C, 34.42; H, 4.96. H NMR (δ, acetone-d6, 20
712.0 Hz, PF6). IR (KBr, cm-1): 2276 (m, νCN).
°C): 5.69 (m, 1H, CH2dCHCMedCH2), 5.37 (d, 3J HP ) 1.0 Hz,
3
[Ru Cp (P Cy3)(CH3CN)2]P F 6 (2c). This complex has been
prepared analogously to 2a with 1 (100 mg, 0.230 mmol) and
PCy3 (65 mg, 0.230 mmol) as the starting materials. Yield: 146
mg (94%). Anal. Calcd for C27H44F6N2P2Ru: C, 48.14; H, 6.58;
N, 4.16. Found: C, 48.33; H, 6.74; N, 3.99. 1H NMR (δ, CDCl3,
20 °C): 4.51 (s, 5H, Cp), 2.42 (s, 6H, CH3), 2.03-1.77 (m, 18H,
Cy), 1.42-1.17 (m, 15H, Cy). 13C{1H} NMR (δ, CDCl3, 20 °C):
5H, Cp), 3.13 (m, 1H, CH2dCHCMedCH2), 3.03 (m, J HHcis
)
7.4 Hz, 1H, CH2dCHCMedCH2), 2.34 (s, 3H, CH2dCHCMed
2
CH2), 1.84 (d, J HP ) 10.0 Hz, 9H, PMe3), 0.16-0.06 (m, 2H,
CH2dCHCMedCH2). 13C{1H} NMR (δ, acetone-d6, 20 °C):
102.3 (d, 2J CP ) 2.2 Hz, 1C, CH2dCHCMedCH2), 87.7 (5C, Cp),
2
81.9 (d, J CP ) 1.2 Hz, 1C, CH2dCHCMedCH2), 45.2 (d,
2J CP ) 5.5 Hz, 1C, CH2dCHCMedCH2), 42.4 (d, J CP ) 4.9
2
128.7 (2C, NtC), 75.6 (d, J CP ) 2.0 Hz, 5C, Cp), 37.7 (bd,
Hz, 1C, CH2dCHCMedCH2), 24.9 (1C, CH2dCHCMedCH2),
2
1J CP ) 18.1 Hz, 3C, Cy1), 30.6 (s, 6C, Cy4), 28.4 (bd, J CP
)
1
20.4 (d, J CP ) 36.6 Hz, 3C, PMe3). 31P{1H} NMR (δ, acetone-
10.5 Hz, 6C, Cy2,6), 27.1 (bs, 3C, Cy3,5), 4.6 (s, CH3). 31P{1H}
NMR (δ, CDCl3, 20 °C): 47.8 (PCy3), -143.6 (1J PF ) 712.0 Hz,
PF6). IR (KBr, cm-1): 2282, 2271 (m, νCN).
d6, 20 °C): 13.5 (PMe3), -142.7 (1J PF ) 707.8 Hz, PF6).
[Ru Cp (P P h 3)(p y)(CH3CN)]P F 6 (4a ). To a solution of 2a
(100 mg, 0.159 mmol) in acetone (3 mL) was added pyridine
(12.9 µL, 0.159 mmol). The solution was stirred at room
temperature for 1 h. The reaction mixture was evaporated to
dryness, and the residue was redissolved in acetone (1 mL).
Upon addition of Et2O (4 mL), a bright yellow precipitate was
formed, which was collected on a glass frit, washed with Et2O
(3 × 2 mL), and dried in vacuo. Yield: 90 mg (82%). Anal.
Calcd for C30H28F6N2P2Ru: C, 51.95; H, 4.07; N, 4.04. Found:
C, 52.06; H, 4.33; N, 3.88. 1H NMR (δ, CDCl3, 20 °C): 8.54
[Ru Cp (η2:η2-COD)(P P h 3)]P F 6 (3a ). A solution of 2a (253
mg, 0.386 mmol) in 5 mL of acetone was treated with 1.5 equiv
of COD (71 µL, 0.578 mmol), and the mixture was stirred for
1 h at room temperature. After reduction of the volume of the
solution to about 2 mL, addition of Et2O afforded a yellow
powder, which was collected on a glass frit, washed with Et2O
(3 × 5 mL), and dried under vacuum. Yield: 0.244 mg (93%).
Anal. Calcd for C31H32F6P2Ru: C, 54.63; H, 4.73. Found: C,
1
54.62; H, 4.88. H NMR (δ, acetone-d6, 20 °C): 7.70-7.53 (m,
3
4
4
(ddd, J HH ) 4.9 Hz, J HH ) 1.6, J HP ) 1.4, 2H, py2,6), 7.74-
15 H, Ph), 5.35 (m, 2H, COD), 5.08 (d, 3J HP ) 1.0 Hz, 5H, Cp),
4.31 (m, 2H, COD), 2.60 (m, 2H, COD), 2.07 (m, 2H, COD),
1.55 (m, 2H, COD), 1.23 (m, 2H, COD). 13C{1H} NMR (δ,
7.66 (m, 1H, py4), 7.62-7.32 (m, 9H, py,3,5 Ph), 7.17-7.07 (m,
5
8H, Ph), 4.44 (s, 5H, Cp), 2.14 (d, J HP ) 1.4 Hz, 3H, CH3).
13C{1H} NMR (δ, CDCl3, 20 °C): 157.0 (d, J CP ) 2.4 Hz, 2C,
2
2
acetone-d6, 20 °C): 135.7 (d, J CP ) 9.3 Hz, 6C, Ph2,6), 134.7
py2,6), 137.2 (s, 1C, py4), 134.0 (d, J CP ) 40.1 Hz, 3C, Ph1),
1
1
4
(d, J CP ) 48.6 Hz, 3C, Ph1), 131.9 (d, J CP ) 2.8 Hz, 3C, Ph4),
133.8 (d, J CP ) 11.2 Hz, 6C, Ph2,6), 132.8 (d, J CP ) 10.0 Hz,
2
3
129.4 (d, J CP ) 9.7 Hz, 6C, Ph3,5), 89.9 (d, J CP ) 1.0 Hz, 5C,
3
2
1C, NtC), 130.9 (d, J CP ) 2.4 Hz, 3C, Ph4), 129.3 (d, J CP
)
4
3
2
2
Cp), 80.5 (d, J CP ) 5.6 Hz, 2C, COD), 79.0 (d, J CP ) 1.0 Hz,
10.0 Hz, 6C, Ph3,5), 125.8 (s, 2C, py3,5), 77.5 (d, J CP ) 2.4 Hz,
5C, Cp), 4.30 (s, 1C, CH3). 31P{1H} NMR (δ, CDCl3, 20 °C):
54.0 (PPh3), -143.4 (1J PF ) 712.1 Hz, PF6).
2
3
2C, COD), 32.0 (2C, COD), 27.9 (d, J CP ) 1.4 Hz, 2C, COD).
31P{1H} NMR (δ, acetone-d6, 20 °C): 46.3 (PPh3), -142.7
(1J PF ) 707.0 Hz, PF6).
[Ru Cp (P P h 3)(P Me3)(CH3CN)]P F 6 (4b). To a solution of
2b (100 mg, 0.213 mmol) in acetone (3 mL) was added PPh3
(56 mg, 0.213 mmol), and the mixture was stirred for 2 h at
room temperature. After removal of the solvent, a yellow
powder was obtained, which was collected on a glass frit,
washed with Et2O (3 × 5 mL), and dried under vacuum.
Yield: 140 mg (95%). Anal. Calcd for C28H32F6NP3Ru: C, 48.70;
[Ru Cp (η2:η2-COD)(P Me3)]P F 6 (3b). To a solution of 2b (70
mg, 0.149 mmol) in acetone (3 mL) was added COD (92 µL,
0.745 mmol), and the mixture was stirred for 2 h at room
temperature. After removal of the solvent, a yellow powder
was obtained, which was collected on a glass frit, washed with
Et2O (3 × 5 mL), and dried under vacuum. Yield: 60 mg (81%).
Anal. Calcd for C16H26F6P2Ru: C, 38.79; H, 5.29. Found: C,
1
38.94; H, 5.44. 1H NMR (δ, acetone-d6, 20 °C): 5.35 (d, 3J HP
)
H, 4.67; N, 2.03. Found: C, 48.88; H, 4.88; N, 1.91. H NMR
(δ, acetone-d6, 20 °C): 7.52-7.39 (m, 15 H, Ph), 4.72 (s, 5H,
1.1 Hz, 5H, Cp), 4.89 (m, 2H, COD), 4.75 (m, 2H, COD), 2.49
5
5
Cp), 2.36 (vt, J HP ) 1.8 Hz, J HP ) 1.4 Hz, 3H, NtCCH3),
(m, 2H, COD), 2.35 (m, 2H, COD), 2.11-2.05 (m, 4H, COD),
1.35 (dd, J HP ) 9.5 Hz, J HP ) 0.7 Hz, 9H, PMe3). 13C{1H}
2
4
2
1.92 (d, J HP ) 9.7 Hz, 9H, PMe3). 13C{1H} NMR (δ, acetone-
1
3
2
NMR (δ, acetone-d6, 20 °C): 137.5 (dd, J CP ) 42.1 Hz, J CP
)
d6, 20 °C): 87.4 (d, J CP ) 1.2 Hz, 5C, Cp), 77.2 (2C, COD),
1.5 Hz, 3C, Ph1), 135.2 (d, J CP ) 11.0 Hz, 6C, Ph2,6), 131.8 (d,
2
2
75.9 (d, J CP ) 5.5 Hz, 2C, COD), 32.2 (2C, COD), 29.3 (d,
4J CP ) 2.4 Hz, 3C, Ph4), 130.0 (d, J CP ) 9.8 Hz, 6C, Ph3,5),
3
1
3J CP ) 2.4 Hz, 2C, COD), 20.5 (d, J CP ) 31.7 Hz, 3C, PMe3).
4
31P{1H} NMR (δ, acetone-d6, 20 °C): 7.3 (PMe3), -142.7
(1J PF ) 708.3 Hz, PF6).
130.0 (1C, NtCCH3), 83.0 (vt, J CP ) 1.8 Hz, 5C, Cp), 21.1 (d,
1J CP ) 29.9 Hz, 3J CP ) 1.2 Hz, 3C, PMe3), 4.7 (s, 1C, NtCCH3).
31P{1H} NMR (δ, acetone-d6, 20 °C): 53.3 (d, J PP ) 40.7 Hz,
2
[Ru Cp (η4-CH2dCHCHdCH2)(P Me3)]P F 6 (3c). A solution
of 2b (100 mg, 0.213 mmol) in CH2Cl2 (3 mL) was saturated
with 1,3-butadiene and then stirred for 2 h at room temper-
ature. After removal of the solvent, a gray powder was
obtained, which was collected on a glass frit, washed with Et2O
(3 × 5 mL), and dried under vacuum. Yield: 85 mg (90%).
PPh3), 1.0 (d, 2J PP ) 40.7 Hz, PMe3), -142.7 (1J PF ) 707.0 Hz,
PF6).
[Ru Cp (P P h 3)(P Cy3)(CH3CN)]P F 6 (4c). This complex has
been prepared analogously to 4b with 2a and PCy3 as the
starting materials: Yield: 93%. Anal. Calcd for C43H56F6NP2-

[RuCp(PR3)(CH3CN)2]PF6
Organometallics, Vol. 18, No. 19, 1999 3845
Ru: C, 59.78; H, 6.53; N, 1.62. Found: C, 59.81; H, 6.66; N,
1J CP ) 22.2 Hz, PCH2CH2N), 3.6 (1C, NtCCH3). 31P{1H} NMR
(δ, CD3NO2, 20 °C): 66.3 (PPh2), -145.9 (1J PF ) 711.7 Hz, PF6).
Ru Cp (a ca c)(CO) (6a ). To a solution of 1 (100 mg, 0.230
mmol) in CH2Cl2 (5 mL) were added acetylacetone (23.6 µL,
0.230 mmol) and NEt3 (32 µL, 0.230 mmol), and the reaction
mixture was stirred at room temperature for 30 min. Subse-
quently, CO was bubbled through the solution for 1 min,
whereupon the reaction mixture changed from dark brown to
yellow. The solvent was removed under reduced pressure, and
the residue was dissolved in 3 mL of Et2O. Insoluble materials
were removed by filtration. The filtrate was evaporated to
dryness, resulting in a dark yellow oil which slowly transforms
into small shiny crystals. Yield: 55 mg (81%). Anal. Calcd for
1
1.76. H NMR (δ, acetone-d6, 20 °C): 7.50 (m, 15 H, Ph), 4.78
5
(s, 5H, Cp), 2.47 (vt, J HP ) 1.4 Hz, 3H, NtCCH3), 2.10-1.0
(m, 33H, PCy3). 13C{1H} NMR (δ, acetone-d6, 20 °C): 137.5-
4
129,0 (18C, Ph), 132.7 (1C, NtC), 81.5 (vt, J CP ) 2.0 Hz, 5C,
Cp), 39.5-27.0.1 (18C, PCy3), 4.5 (s, 1C, CH3). 31P{1H} NMR
2
(δ, acetone-d6, 20 °C): 44.6 (d, J PP ) 33.1 Hz, PPh3), 39.6 (d,
2J PP ) 33.1 Hz, PCy3), -142.6 (1J PF ) 707.5 Hz, PF6).
[Ru Cp (P P h 3)(AsP h 3)(CH3CN)]P F 6 (4d ). This complex
has been prepared analogously to 4b with 2a and AsPh3.
Yield: 96%. Anal. Calcd for C43H38F6NP2AsRu: C, 56.09; H,
4.16. Found: C, 56.13; H, 4.05. 1H NMR (δ, acetone-d6, 20
°C): 7.53-7.09 (m, 30H, Ph), 4.58 (s, 5H, Cp), 2.17 (d, J PH
)
1
1.54 Hz, 3H, CH3). 13C{1H} NMR (δ, acetone-d6, 20 °C): 139-
129 (36C, Ph), 130 (s, 1C, CN), 81.6 (d, J CP ) 2 Hz, 5C, Cp),
4.3 (s, 1C, CH3). 31P{1H} NMR (δ, acetone-d6, 20 °C): 46.5
(PPh3), -143.4 (PF6).
C11H12O3Ru: C, 45.05; H, 4.12. Found: C, 45.08; H, 4.21. H
NMR (δ, CDCl3, 20 °C): 5.31 (s, 1H, MeCOCHCOMe), 4.92 (s,
5H, Cp), 1.92 (s, 6H, MeCOCHCOMe). 13C{1H} NMR (δ, CDCl3,
20 °C): 204.9 (1C, CO), 189.2 (2C, MeCOCHCOMe), 102.0 (1C,
MeCOCHCOMe), 80.1 (5C, Cp), 27.6 (2C, MeCOCHCOMe). IR
(CH2Cl2, cm-1): 1949 (s, νCO).
[Ru Cp (η2:η2-COD)(CH3CN)]P F 6 (5a ). To a solution of 1
(187 mg, 0.430 mmol) in CH2Cl2 (8 mL) was added COD (80
µL, 0.648 mmol), and the mixture was stirred for 2 h at room
temperature. After removal of the solvent, a yellow powder
was obtained, which was collected on a glass frit, washed with
Et2O (3 × 5 mL), and dried under vacuum. Yield: 192 mg
(97%). Anal. Calcd for C15H20F6NPRu: C, 39.13; H, 4.38; N,
Ru Cp (oxin a te)(CO) (6b). To a solution of 1 (150 mg, 0.345
mmol) in CH2Cl2 (5 mL) was added potassium 8-quinolin-8-
olate (oxinate) (74 mg, 0.345 mmol), and the reaction mixture
was stirred at room temperature for 30 min. Subsequently,
CO was bubbled through the solution for 1 min, whereupon
the reaction mixture changed from dark brown to yellow. The
solvent was evaporated under reduced pressure. The residue
was redissolved in 3 mL of Et2O, and insoluble materials were
removed by filtration. The filtrate was evaporated to dryness,
resulting in a dark yellow oil. The product was purified by
column chromatography (silica gel). The column was eluted
with CH2Cl2 until the solution was colorless and then with
acetone, at which point the first brown band was collected.
The solvent was removed under reduced pressure, resulting
in a dark yellow oil, which was dried under vacuum. Yield:
50 mg (43%). Anal. Calcd for C15H11NO2Ru: C, 53.25; H, 3.28;
N, 4.14. Found: C, 53.44; H, 3.35; N, 3.80. 1H NMR (δ, CDCl3,
1
3.04. Found: C, 39.36; H, 4.17; N, 2.83. H NMR (δ, acetone-
d6, 20 °C): 5.67 (m, 2H, COD), 5.29 (s, 5H, Cp), 4.37 (m, 2H,
COD), 2.68 (s, 3H, NtC), 2.42 (m, 2H, COD), 2.30-2.05 (m,
6H, COD). 13C{1H} NMR (δ, acetone-d6, 20 °C): 133.2 (1C, Nt
C), 86.8 (2C, COD), 85.5 (2C, COD), 85.4 (5C, Cp), 32.3 (2C,
COD), 28.00 (2C, COD), 4.33 (1C, NtCCH3).
[Ru Cp (η4-CH2dCHCHdCH2)(CH3CN)]P F 6 (5b). A solu-
tion of 1 (2.98 g, 6.86 mmol) in CH2Cl2 (300 mL) was saturated
with 1,3-butadiene and was then stirred at room temperature
for 24 h. During that time the solution was purged several
times with 1,3-butadiene. On removal of the solvent, a bright
yellow solid was obtained, which was collected on a glass frit,
washed with Et2O, and dried under vacuum. Yield: 2.38 g
(85%). Anal. Calcd for C11H14F6NPRu: C, 32.52; H, 3.47; N,
3
4
20 °C): 8.59 (dd, J HH ) 4.8 Hz, J HH ) 1.2 Hz, 1H, H2), 8.06
(dd, J HH ) 8.4 Hz, J HH ) 1.2 Hz, 1H, H4), 7.35 (dd, dd,
3
4
3J HH ) 8.0 Hz, J HH ) 7.6 Hz, 1H, H6), 7.15 (dd, J HH ) 8.4
3
3
1
Hz, J HH ) 4.8 Hz, 1H, H3), 6.99 (d, J HH ) 8.0 Hz, 1H, H5),
6.81 (d, 3J HH ) 8.0 Hz, 1H, H7), 5.03 (s, 5H, Cp). 13C{1H} NMR
(δ, CDCl3, 20 °C): 202.5 (1C, CO), 171.6 (1C, C8), 152.5 (1C,
C2), 146.8 (1C, C8a), 137.5 (1C, C4), 131.0 (1C, C4a), 130.7 (1C,
C6), 121.9 (1C, C3), 115.6 (1C, C5), 110.4 (1C, C7), 81.6 (5C,
Cp).
3
3
3.45. Found: C, 32.41; H, 3.30; N, 3.50. H NMR (δ, acetone-
d6, 20 °C): 5.88 (m, 2H), 5.41 (s, 5H), 4.13 (d, 2H, J ) 7.5 Hz),
2.64 (s, 3H), 1.52 (d, 2H, J ) 9.8 Hz).13C{1H} NMR (δ, acetone-
d6, 20 °C): 136.1 (1C, NtC), 89.9 (2C, CH2dCH), 85.4 (5C,
Cp), 53.4 (2C, CHdCH2), 5.1 (1C, CH3).
[Ru Cp (Me2NCH2CH2NMe2)(CH3CN)]P F 6 (5c). 1 (349 mg,
0.803 mmol) and Me2NCH2CH2NMe2 (112.1 mg, 0.964 mmol)
in Et2O (15 mL) were stirred at room temperature for 15 h.
After evaporation of the solvent, the pale yellow residue was
dried in vacuo. Yield: 350 mg (93%). Anal. Calcd for C13H24F6N3-
PRu: C, 33.34; H, 5.16; N, 8.97. Found: C, 33.38; H, 5.19; N,
9.09. 1H NMR (δ, acetone-d6, -30 °C): 4.10 (s, 5H), 3.29
(s, 6H), 2.75 (s, 6H), 2.69 (m, 2H), 2.63 (s, 3H), 2.42 (m, 2H).
3C{1H} NMR (δ, acetone-d6, -30 °C): CN not observed, 68.5
(s, 5C, Cp), 62.6 (s, 2C, NCH3), 59.0 (s, 2C, CH2), 54.7 (s, 2C,
NCH3), 4.6 (CH3). IR (KBr, cm-1): 2254 (s, νCN).
[Ru Cp (P h 2P CH2CH2NMe2)(CH3CN)]P F 6 (5d ). A solution
of 1 (145 mg, 0.334 mmol) was treated with Ph2PCH2CH2NMe2
(87 mg, 0.334 mmol) in acetone (3 mL). After the mixture was
stirred for 1 h, the product was precipitated by addition of Et2O
(25 mL). Yield: 185 mg (91%). Anal. Calcd for C23H28F6N2P2-
Ru: C, 45.32; H, 4.63; N, 4.60. Found: C, 45.38; H, 4.89; N,
4.39. 1H NMR (δ, CD3NO2, 20 °C): 7.18-7.42 (m, 10H, Ph),
4.47 (s, 5H, Cp), 3.07 (s, 3H, NMe), 3.02 (s, 3H, NMe), 2.62-
2.30 (m, 4H), 1.96 (s, 3H, Me). 13C{1H} NMR (δ, CD3NO2, 20
Ru Cp (5-Cl-oxin a te)(CO) (6c). To a solution of 1 (100 mg,
0.230 mmol) in CH2Cl2 (5 mL) was added 5-chloroquinolin-8-
olate (5-Cl-oxinate), potassium salt (50 mg, 0.230 mmol), and
the reaction mixture was stirred at room temperature for 30
min. Subsequently, CO was bubbled through the solution for
1 min, whereupon the reaction mixture changed from dark
brown to yellow. The solvent was evaporated under reduced
pressure. The residue was extracted with 100 mL of Et2O. The
filtrate was evaporated to dryness, resulting in a dark yellow
oil, which was dried under vacuum. Yield: 45 mg (52%). Anal.
Calcd for C15H10ClNO2Ru: C, 48.33; H, 2.70; N, 3.76. Found:
C, 48.51; H, 2.85; N, 3.83. DC: Rf(CH2Cl2/acetone 1/1 (v/v)) )
1
2
°C): 139.1 (d, J CP ) 47.6 Hz, 1C, Ph1), 135.0 (d, J CP ) 11.6
Hz, 2C, Ph2,6), 132.5 (d, J CP ) 11.1 Hz, 2C, Ph2′,6′), 131.9 (d,
2
1
3
0.72). H NMR (δ, CDCl3, 20 °C): 8.66 (d, J HH ) 4.7 Hz, 1H,
4J CP ) 2.3 Hz, 1C, Ph4), 131.3 (d, 4J CP ) 2.3 Hz, 1C, Ph4′), 131.2
(d, 1J CP ) 41.6 Hz, 1C, Ph1′), 130.2 (d, 3J CP ) 10.2 Hz, 2C, Ph3,5),
H2), 8.38 (d, J HH ) 8.6 Hz, 1H, H4), 7.40 (s, 1H, H6), 7.28 (dd,
3
3J HH ) 8.6 Hz, J HH ) 4.7 Hz, 1H, H3), 6.90 (s, J HH ) 8.0 Hz,
1H, H7), 5.04 (s, 5H, Cp). 13C{1H} NMR (δ, CDCl3, 20 °C):
201.9 (1C, CO), 170.7 (1C, C8), 152.8 (1C, C2), 147.0 (1C, C8a),
134.8 (1C, C4), 130.1 (1C, C4a), 128.1 (1C, C6), 122.6 (1C, C3),
3
3
130.05 (d, J CP ) 10.2 Hz, 2C, Ph3′,5′), 130.0 (d, J CP ) 8.3 Hz,
3
3
2
2
1C, NC), 76.9 (d, J CP ) 2.8 Hz, 5C, Cp), 64.0 (d, J CP ) 6.5
Hz, PCH2CH2N), 58.7 (1C, NMe2), 57.8 (1C, NMe2), 30.0 (d,

3846 Organometallics, Vol. 18, No. 19, 1999
Ru¨ba et al.
115.0 (1C, C5), 112.1 (1C, C7), 81.6 (5C, Cp). IR (CH2Cl2,
cm-1): 1946 (s, νCO).
Author: Assignment of C2 for the 152.8 ppm resonance OK?
[Ru Cp (η3-CH2CHCH2)(CH3CN)Br ]P F 6 (7). To a solution
of 1 (300 mg, 0.690 mmol) in 6 mL of acetone was slowly added
CH2dCHCH2Br (59.7 µL, 0.690 mmol). The mixture was
stirred at room temperature for 1 h. The solvent was then
removed in vacuo and the residue redissolved in CH2Cl2 (1
mL). On addition of Et2O (5 mL) an orange precipitate was
formed, which was collected on a glass frit, washed with Et2O
(4 × 1 mL), and dried in vacuo. Yield: 297 mg (91%). Anal.
Calcd for
C10H13BrF6NPRu: C, 25.38; H, 2.77; N, 2.96.
Found: C, 25.55; H, 2.86; N, 2.95. 1H NMR (δ, CDCl3/CD3-
NO2 1/1 (v/v), 20 °C): 5.87 (s, 5H, Cp), 5.02 (m, 1H, CH), 4.67
3
2
(dd, J HHcis ) 6.3 Hz, J HH ) 3.2 Hz, 1H, CH2), 4.16 (dd,
3J HHcis ) 5.8 Hz, J HH ) 3.2 Hz, 1H, CH2), 4.01 (d, J HHtrans
)
2
3
3
11.3 Hz, 1H, CH2), 3.85 (d, J HHtrans ) 11.0 Hz, 1H, CH2-
CHCH2), 2.41 (s, 3H, NtCCH3). 13C{1H} NMR (δ, CDCl3/CD3-
NO2 1/1 (v/v), 20 °C): 132.8 (NtC), 99.7 (CH), 94.5 (5C, Cp),
69.1 (CH2), 61.9 (CH2), 4.1 (CH3). 31P{1H} NMR (δ, CDCl3/CD3-
NO2 1/1 (v/v), 20 °C): -140.4 (1J PF ) 710.0 Hz, PF6).
F igu r e 1. Peak area, as a function of time, of the 1H NMR
signal of coordinated CH3CN after addition of CD3CN (8.1
µL, 30.81 mM) to a solution of [RuCp(PMe3)(CH3CN)2]+ (2b;
25 mM) in CD3NO2 at 295 K.
[Ru Cp (η3-CH2CHCH2)(P P h 3)Br ]P F 6 (8a ). A solution of
2a (278 mg, 0.424 mmol) in acetone (8 mL) was treated with
CH2dCHCH2Br (74 µL, 0.848 mmol), and the mixture was
stirred for 1 h, whereupon the color changed from yellow to
orange. The solvent and unreacted CH2dCHCH2Br were
removed under reduced pressure. The resulting dark orange
powder was washed with Et2O and dried under vacuum.
Yield: 242 mg (85%). Anal. Calcd for C26H25BrF6P2Ru: C,
added NEt3 (50 µL, 1.2 equiv). Stirring for 2 h led to
precipitation of an orange microcrystalline solid, which was
collected on a glass frit, washed with 5 mL of Et2O/acetone
(1:1), and dried in vacuo. Yield: 197 mg (83%). Anal. Calcd
for C32H40BrF6NP2Ru: C, 48.31; H, 5.07; N, 1.76. Found: C,
48.62; H, 5.04; N, 1.71. 1H NMR (δ, CD3NO2, 20 °C): 7.61-
3
7.27 (m, 15H, Ph), 5.06 (s, 5H, Cp), 4.43 (dd, J HHtrans ) 12.8
1
2
44.97; H, 3.63. Found: C, 45.08; H, 3.51. H NMR (δ, CDCl3/
Hz, J HH ) 2.0 Hz, 1H, H2CdCH), 3.54-3.09 (m, 8H, H2Cd
CD3NO2 1/1 (v/v), 20 °C): 7.41-7.25 (m, 15H, Ph), 5.86 (s, 5H,
Cp), 4.75-4.65 (m, 2H, CH2CH), 4.08-3.94 (m, 1H, CH2),
3.79-3.72 (m, 1H, CH2), 3.61 (d, 3J HHtrans ) 11.2 Hz, 1H, CH2).
13C{1H} NMR (δ, CDCl3, 20 °C): 134.9-129.0 (m, 15C, Ph),
CHCH2, N(CH2CH3)3), 2.83-2.51 (m, 2H, H2CdCHCH2), 1.34
(t, 9H, N(CH2CH3)3). 13C{1H} NMR (δ, CDCl3, 20 °C): 136.0-
133.0 (m, 9C, Ph1,2,6), 131.8-131.6 (m, 3C, Ph4), 129.7-129.2
2
(m, 6C, Ph3,5), 87.8 (d, J CP ) 2.8 Hz, 5C, Cp), 65.8 (bs, 1C,
2
2
97.7 (d, J CP ) 1.6 Hz, 1C, CH), 94.6 (d, J CP ) 1.1 Hz, 5C,
H2CdCH), 54.7 (1C, H2CdCHCH2), 53.0-52.9 (m, 3C, N(CH2-
CH3)3), 44.1 (d, 2J CP ) 2.8 Hz, 1C, CH2dCH), 7.9 (s, 3C, N(CH2-
CH3)3). 31P{1H} NMR (δ, CD3NO2, 20 °C): 52.1 (PPh3), -143.5
(1J PF ) 707.0 Hz, PF6).
Aceton itr ile Exch a n ge Kin etics. The method of investi-
gation depended on the rate of reaction. In the case of 2a and
2b, the rate constants are small (<0.1 s-1), and the exchange
according to eq 1
2
2
Cp), 68.4 (d, J CP ) 3.8 Hz, 1C, CH2), 55.5 (d, J CP ) 2.7 Hz,
1C, CH2). 31P{1H} NMR (δ, CDCl3/CD3NO2 1/1 (v/v), 20 °C):
33.7 (PCy3), -143.3 (1J PF ) 710.2 Hz, PF6).
[Ru Cp (η3-CH2CHCH2)(P Me3)Br ]P F 6 (8b). This complex
has been prepared analogously to 8a with 2b as the starting
material. Yield: 94%. Anal. Calcd for C11H19BrF6P2Ru: C,
26.00; H, 3.77. Found: C, 26.22; H, 3.95. 1H NMR (δ, acetone-
3
d6, 20 °C): 6.07 (s, 5H, Cp), 4.54 (dd, 1H, J HH ) 11.1 Hz,
2J HH ) 2.1 Hz, CH2), 4.50-4.34 (m, 1H, CH), 4.28-4.21 (m,
1H, CH2), 3.92-3.81 (m, 1H, CH2), 3.38 (d, 3J HHtrans ) 10.4 Hz,
1H, CH2). 13C{1H} NMR (δ, acetone-d6, 20 °C): 97.5 (s, 1C,
[RuCp(PR3)(CH3CN)2]PF6 + 2CD3CN f
[RuCp(PR3)(CD3CN)2]PF6 + 2CH3CN (1)
2
2
CH), 94.4 (d, J CP ) 1.1 Hz, 5C, Cp), 63.0 (d, J CP ) 3.3 Hz,
was studied as a function of temperature and CD3CN concen-
tration by monitoring the increase in intensity of the proton
NMR signal of free CH3CN (at 1.97 ppm) and the decrease of
the bound CH3CN (a doublet in the range of 2.12-2.42 ppm)
after fast injection of CD3CN into solutions of 2a ,b in CD3-
NO2. Figure 1 shows a typical example of a kinetic run. The
time dependence of the mole fraction x ) [CH3CN]c/([CH3-
CN]c + [CH3CN]f) of coordinated nondeuterated acetonitrile,
obtained by integration of the signals (the peak area is
proportional to x), was fitted to eq 213
1C, CH2), 54.2 (d, J CP ) 3.3 Hz, 1C, CH2). 31P{1H} NMR (δ,
2
acetone-d6, 20 °C): 10.0 (PMe3), -142.7 (1J PF ) 707.6 Hz, PF6).
[Ru Cp (η3-CH2CHCH2)(P Cy3)Br ]P F 6 (8c). To a solution
of 2c (207 mg, 0.307 mmol) in acetone (4 mL) was slowly added
BrCH2CHdCH2 (36.6 µL mg, 0.307 mmol). The reaction
mixture was stirred at room temperature for 1 h, whereupon
the color changed from yellow to orange. The solvent was
removed in vacuo and the residue redissolved in 1 mL of CH2-
Cl2. On addition of Et2O (3 mL) a bright yellow precipitate
formed, which was collected on a glass frit, washed with Et2O
(3 × 1 mL), and dried in vacuo. Yield: 208 mg (95%). Anal.
Calcd for C26H43BrF6P2Ru: C, 43.83; H, 6.08. Found: C, 44.06;
x ) x∞ + (xo - x∞) exp[-kt/(1 - x∞)]
(2)
1
H, 6.41. H NMR (δ, CDCl3, 20 °C): 5.94 (s, 5H, Cp), 4.66 (m,
where x0 and x∞ are the values of x at t ) 0 and ∞, and k is the
observed first-order rate constant for the exchange of a
particular solvent molecule. The adjustable parameters were
x0, x∞, and k. In the case of 2c, the CH3CN exchange is faster
and can be followed by NMR line broadening. From the
variable-temperature NMR studies, exchange rate constants
were determined by visual comparison of the observed and
computer-simulated spectra using the DNMR3 program.14
3
1H, CH2), 4.50 (dd, J HHtrans ) 11.2 Hz, J ) 2.6 Hz, 1H, CH2),
3
4.23 (m, 1H, CH), 3.92 (m, 1H, CH2), 3.23 (d, J HHtrans ) 10.9
Hz, 1H, CH2), 2.55-1.21 (m, 33H, Cy). 13C{1H} NMR (δ, CDCl3,
2
20 °C): 93.2 (CH2CHCH2), 92.9 (5C, Cp), 69.3 (d, J CP ) 3.3
Hz, CH2CHCH2), 53.9 (d, 2J CP ) 4.2 Hz, CH2CHCH2), 37.0 (bd,
2
1J CP ) 18.2 Hz, 3C, Cy1), 30.7 (bs, 6C, Cy3,5), 28.2 (bd, J CP
)
10.4 Hz, 6C, Cy2,6), 26.5 (bs, 3C, Cy4). 31P{1H} NMR (δ, CDCl3,
20 °C): 31.9 (PCy3), -143.5 (1J PF ) 713.3 Hz, PF6).
[Ru Cp (η2-CH2dCHCH2NEt3)(P P h 3)Br ]P F 6 (9). To a sus-
pension of 8a (208 mg, 0.299 mmol) in acetone (8 mL) was
(13) Helm, L.; Elding, L. I.; Merbach, A. E. Inorg. Chem. 1985, 24,
1719.

[RuCp(PR3)(CH3CN)2]PF6
Organometallics, Vol. 18, No. 19, 1999 3847
Sch em e 1
Ta ble 1. Str u ctu r e a n d Rea ctivity of
crystal decay, and for absorption were applied. All structures
were solved by direct methods using the program SHELXS97.16
Structure refinement on F2 was carried out with the program
SHELXL97.17 All non-hydrogen atoms were refined anisotro-
pically. Hydrogen atoms were inserted in idealized positions
and were refined riding with the atoms to which they were
bonded.
[Ru Cp (CH3CN)3]+ (1), [Ru Cp (P P h 3)(CH3CN)2]+ (2a ),
[Ru Cp (P Me3)(CH3CN)2]+ (2b),
[Ru Cp (P Cy3)(CH3CN)2]+ (2c), a n d
[Ru Cp (Me2NCH2CH2NMe2)(CH3CN)]+ (5b)
1a
2a
2b
2c
5b
Ru-N(av), Å 2.083(1)
Ru-P, Å
2.056(3) 2.053(2)
2.294(1) 2.359(1)
2.177(5) 2.185(3)
1.136(4) 1.135(4)
Ru-C5(av), Å 2.135(3)
Resu lts a n d Discu ssion
CtN(av), Å
∆Hq, kcal
mol-1
1.131(3)
20.7 (
0.5
14.2 (
1.7
25.9 (
0.5
16.8 (
1.8
25.0 (
0.3
21.3 (
1.0
15.4 (
0.6
3.2 (
Syn th esis a n d Su bstitu tion Rea ction s of [Ru Cp -
(P R3)(CH3CN)2]P F 6. Treatment of 1 with 1 equiv of
the monodentate ligands PR3 (R ) Ph, Me, Cy) at room
temperature affords the cationic complexes [RuCp-
(PR3)(CH3CN)2]PF6 (2a -c) in essentially quantitative
∆Sq, cal K-1
mol-1
14.3 (
0.8
12.7 (
2.3
2.2
167
k298, s-1
5.6
2.9‚10-3 2.7‚10-3 0.38
mechanism
D
D
D
D
D (Id)
1
a
yields as monitored by H NMR spectroscopy (Scheme
Reference 18.
1). The complexes are stable to air in the solid state but
decompose slowly in solutions exposed to air. Charac-
Temperature readings were calibrated by using the method
of Raiford et al.,15 corrected to 250.13 MHz, by adding a
capillary of methanol to the experimental sample. The tem-
perature dependence of the rate constants is given by the
Eyring equation (eq 3).
1
terization was by H, 13C{1H}, and 31P{1H} NMR and
1
IR spectroscopy as well as elemental analysis. The H
NMR spectra of 2a -c bear no unusual features. Thus,
the Cp ligand exhibits a singlet at about 4.5 ppm and
the proton resonance of the CH3CN ligand gives a
doublet in the range of 2.1-2.4 ppm. In the 31P{1H}
NMR spectra of 2a -c the phosphine ligand exhibits
respectively a singlet at 51.7, 5.4, and 47.8 ppm.
The solid-state structures of 2b and 2c were deter-
mined by single-crystal X-ray diffraction. ORTEP dia-
grams of 2b and 2c are depicted in Figures 2 and 3 with
important bond distances and angles reported in the
captions. Both complexes adopt typically a three-legged
piano-stool conformation. It is interesting to note that
in 2b the Ru-C(1) bond trans to the PMe3 ligand is
significantly longer (2.217(3) Å) than the other Ru-C
bonds that range from 2.153(4) to 2.179(4) Å. Similarly
k ) (kBT/h)(exp(-(∆Hq - T∆Sq)/RT)
(3)
X-r a y Str u ctu r e Deter m in a tion for 2b, 2c, a n d 9‚
CH2Cl2. Crystals of 2b, 2c, and 9‚CH2Cl2 were obtained by
diffusion of Et2O into CH2Cl2 solutions. Crystal data and
experimental details are given in Table 2. X-ray data for 2b
and 2c were collected on a Siemens Smart CCD area detector
diffractometer (graphite-monochromated Mo KR radiation,
λ ) 0.710 73 Å, a nominal crystal-to-detector distance of 4.45
cm, 0.3° ω-scan frames). For 9‚CH2Cl2 X-ray data were
collected on a Philips PW 1100 four-circle diffractometer using
graphite-monochromated Mo KR radiation and the θ-2θ scan
technique. Corrections for Lorentz and polarization effects, for
(14) (a) Binsch, G.; Kleier, D. DNMR3; QCPE; Indiana University,
Bloomington, IN, 1970; Program 165. (b) Binsch, G.; Kessler, H. Angew.
Chem. 1980, 92, 445.
(15) Raiford, D. S.; Fisk, C. L.; Becker, E. D. Anal. Chem. 1979, 51,
2050.
(16) Sheldrick, G. M. SHELXS97: Program for the Solution of
Crystal Structures; University of Go¨ttingen, Go¨ttingen, Germany,
1997.
(17) Sheldrick, G. M. SHELXL97: Program for Crystal Structure
Refinement; University of Go¨ttingen, Go¨ttingen, Germany, 1997.

3848 Organometallics, Vol. 18, No. 19, 1999
Ta ble 2. Cr ysta llogr a p h ic Da ta for 2b, 2c, a n d 9‚CH2Cl2
Ru¨ba et al.
2b
2c
9‚CH2Cl2
formula
fw
C12H20F6N2P2Ru
469.31
C27H44F6N2P2Ru
637.65
C33H42BrCl2F6NP2Ru
880.50
cryst size, mm
space group
a, Å
b, Å
c, Å
R, deg
â, deg
γ, deg
V, Å3
0.60 × 0.50 × 0.28
P212121 (No. 19)
8.307(2)
12.383(3)
18.014(4)
0.30 × 0.10 × 0.03
0.66 × 0.55 × 0.41
P1h (No. 2)
9.394(2)
13.560(4)
15.551(3)
89.75(2)
75.97(2)
73.07(2)
1833.9(8)
2
1.595
298(2)
1.805
empirical
748
Cc (No. 9)
14.224(3)
14.906(4)
15.011(4)
106.44(1)
1853.0(8)
4
1.682
295(2)
1.070
multiscan
936
3053(1)
4
1.466
295(2)
0.674
multiscan
1392
Z
F
T, K
calcd, g cm-3
µ(Mo KR), mm-1
abs cor
F(000)
min/max transmissn factors
0.75/0.58
30
0.80/0.72
30
0.75/0.65
25
-10 e h e 11
-16 e k e 16
0 e l e 18
6405
6405
5665
476
0.029
θ
max, deg
index ranges
-8 e h e 11
-14 e k e 17
-24 e l e 20
13 153
5223
4960
236
0.031
0.034
-20 e h e 19
-20 e k e 20
-20 e l e 20
21 969
8697
8213
348
0.030
0.033
no. of rflns measd
no. of unique rflns
no. of rflns, I > 2σ(I)
no. of params
R1 (I > 2σ(I))a
R1 (all data)a
0.035
0.073
-0.32/0.36
wR2 (all data)a
0.085
-0.30/0.36
0.081
-0.44/0.61
min/max diff Fourier peaks, e Å-3
R1 ) ∑||Fo| - |Fc||/∑|Fo|; wR2 ) [∑(w(Fo - Fc2)2)/∑(w(Fo2)2)]1/2
.
a
2
F igu r e 2. Structural view of [RuCp(PMe3)(CH3CN)2]PF6
(2b) showing 20% thermal ellipsoids (PF6 omitted for
F igu r e 3. Structural view of [RuCp(PCy3)(CH3CN)2]PF6
(2c) showing 20% thermal ellipsoids (PF6 omitted for
-
-
clarity). Selected bond lengths (Å) and angles (deg): Ru-
(1)-C(1-5)av ) 2.177(5), Ru-P(1) ) 2.294(1), Ru-N(1) )
2.054(3), Ru-N(2) ) 2.059(3), C(1)-C(2) ) 1.359(9), C(2)-
C(3) ) 1.430(9), C(3)-C(4) ) 1.442(9), C(4)-C(5) ) 1.381-
(9), C(1)-C(5) ) 1.370(9), N(1)-C(9) ) 1.135(4); N(2)-Ru-
C(11) ) 1.137(4), C(9)-N(1)-Ru ) 179.5(3), C(11)-N(2)-
Ru ) 177.2(3), N(1)-Ru-N(2) ) 85.9(1), N(1)-Ru-P(1) )
93.5(1), N(2)-Ru-P(1) ) 90.7(1).
clarity). Selected bond lengths (Å) and angles (deg): Ru-
(1)-C(1-5)av ) 2.185(3), Ru-P(1) ) 2.359(1), Ru-N(1) )
2.050(2), Ru-N(2) ) 2.056(2), C(1)-C(2) ) 1.443(3), C(2)-
C(3) ) 1.465(7), C(3)-C(4) ) 1.365(7), C(4)-C(5) ) 1.396-
(5), C(1)-C(5) ) 1.407(5), N(1)-C(24) ) 1.142(4), N(2)-
C(26) ) 1.128(4); C(24)-N(1)-Ru ) 171.2(3), C(26)-N(2)-
Ru ) 172.9(3), N(1)-Ru-N(2) ) 89.5(1), N(1)-Ru-P(1) )
89.1(1), N(2)-Ru-P(1) ) 89.7(1).
in 2c, the Ru-C(3) and Ru-C(4) bonds are long (2.203
and 2.205 Å, respectively) and the Ru-C(1), Ru-C(2),
and Ru-C(5) bonds are short (2.169, 2.169, and 2.180
Å, respectively). Whereas the Ru-N distances are
practically invariant in 2b and 2c, the Ru-P(1) bond
lengths are significantly different (see Table 1). Note
further the angles between the central axis and the
Ru-N and Ru-P bonds: while in 2b these angles are
52.0 (cf. 52.8° in 1) and 56.3°, respectively, in 2c they
are 56.3 and 54.1°.
The kinetic results of the exchange of CH3CN are
included in Table 1. It is seen that CH3CN is much less
labile in 2a and 2b compared to 1,18 mainly due to
higher activation enthalpies. In contrast, the lability of
CH3CN in 2c approaches that in 1. Nevertheless, the

[RuCp(PR3)(CH3CN)2]PF6
Organometallics, Vol. 18, No. 19, 1999 3849
Sch em e 2
F igu r e 4. Linear free energy relationship for the CH3CN
exchange in [RuCp(CH3CN)3]+ (1), [RuCp(PPh3)(CH3CN)2]+
(2a ), [RuCp(PMe3)(CH3CN)2]+ (2b ), [RuCp(PCy3)(CH3-
CN)2]+ (2c), and [RuCp(Me2NCH2CH2NMe2)(CH3CN)]+
(5c).
react with 2b to give [RuCp(PMe3)(η4-CH2dCHCHd
CH2)]+ (3d) and [RuCp(PMe3)(η4-CH2dC(Me)CHdCH2)]+
(3e), respectively (Scheme 1). Further, 2a has been
reacted with the monodentate ligands py, PMe3, PCy3,
and AsPh3, giving the chiral complexes [RuCp(PPh3)-
(L)(CH3CN)]+ (4a -d ) in high yields. The products have
been characterized by NMR spectroscopy and elemental
analyses.
linear trend seen between values of log k and ∆Hq
(Figure 4) points to the operation of a common exchange
mechanism. Since the reaction rate is unaffected by the
free CH3CN concentration, a unimolecular process (dis-
sociative mechanism, D) is indicated. This is further
reflected by positive entropies of activation along with
large activation enthalpies.
As anticipated, complex 1 also reacts readily with the
bidendate ligands L-L ) 1,5-COD, 1,3-butadiene, Me2-
NCH2CH2NMe2, and Ph2PCH2CH2NMe2 to give the
cationic complexes [RuCp(L-L)(CH3CN)]+ (5a -d ) in
good yields (Scheme 2). In the case of L-L ) acac,
oxinate, 5-Cl-oxinate, the intermediates [RuCp(L-L)-
(CH3CN)] could not be isolated but were trapped as the
stable CO complexes [RuCp(acac)(CO)] (6a ), [RuCp-
(oxinate)(CO)] (6b), and RuCp(5-Cl-oxinate)(CO) (6c)
(Scheme 2). Characterization of all complexes was again
accomplished by a combination of elemental analysis
and 1H, 13C{1H}, and, where possible, 31P{1H} NMR
spectroscopy. Complexes 6b and 6c have also been
characterized by IR spectroscopy.
The role of the phosphine ligands may be discussed
in terms of either nucleophilicity increasing in the order
of pKa values,19 PPh3 (2.73) < PMe3 (8.65) < PCy3 (9.70),
or bulkiness, as expressed by the cone angles,20 PMe3
(118°) < PPh3 (145°) < PCy3 (170°). A comparison of
these orders with the order of the rate constants of Table
1 suggests that the present phosphine ligand effect is
predominantly steric in origin. van der Waals repulsive
interactions between PCy3 and the nitrile ligands are
also reflected by the bond angles described above. Thus,
in 2c, the angle between the central axis and the Ru-N
and Ru-P bond is larger and smaller, respectively, in
comparison to those in 2b. Ligand repulsive energies
ER calculated for some Cr(CO)5PR3 complexes have been
found to be extremely high for R ) Cy.21 It is the value
of ER that may explain why in a series of Cp*Ru(PR3)X
complexes, with X being some σ-donor ligand, only that
with R ) Cy forms (planar) stable 16e complexes.22,23
In these terms the rapid CH3CN exchange in 2c is
obvious.
The CH3CN ligand in [RuCp(Me2NCH2CH2NMe2)(CH3-
CN)]+ (5c) is extremely labile and is readily replaced
by CD3CN in a solution of CD3NO2 at room temperature.
The kinetics of this process has been studied in detail
1
by H NMR spectroscopy as a function of temperature,
with results given in Table 1. Despite the low activation
entropy, the reaction rate is independent of the free CH3-
CN concentration, again pointing to a dissociative
exchange mechanism (D or Id).
The reactivity of complexes 2 has been further inves-
tigated as follows. Treatment of 2a ,b with COD yields
the cationic complexes [RuCp(PR3)(η2:η2-COD)]+ (R )
Ph (3a ), Me (3b)), whereas with 2c no reaction takes
place. Conjugated dienes, e.g., butadiene and isoprene,
Oxid a tive Ad d ition Rea ction s. In addition to sub-
stitution, 1 also undergoes oxidative addition reactions
with allyl halides. Thus, with allyl bromide, the Ru(IV)
η3-allyl complex [RuCp(η3-CH2CHCH2)(CH3CN)Br]PF6
(7) is obtained in 91% isolated yield (Scheme 3).
Similarly, 2a -c give the corresponding Ru(IV) η3-allyl
complexes [RuCp(η3-CH2CHCH2)(PR3)Br]PF6 (8a -c) in
high isolated yields (Scheme 4). All of these complexes
are air stable both in solution and in the solid state.
The 1H NMR spectra show the expected singlet reso-
nances appearing in the ranges 5.87-6.07 ppm and the
characteristic doublet and multiplet resonances assign-
able to the allyl ligands. In the 13C{1H} NMR spectra,
(18) Luginbu¨hl, W.; Zbinden, P.; Pittet, P. A.; Armbruster, T.; Bu¨rgi,
H.-B., Merbach, A. E.; Ludi, A. Inorg. Chem. 1991, 30, 2350.
(19) (a) Golovin, M. N.; Rahman, M. M.; Belemonte, J . E. Giering,
W. P. Organometallics 1985, 4, 1981. (b) Bush, R. C.; Angelici, R. J .
Inorg. Chem. 1988, 27, 681. (c) Chenm, L.; Poe¨, A. J . Coord. Chem.
Rev. 1995, 143, 265.
(20) Tolman, C. A. Chem. Rev. 1977, 77, 313.
(21) Brown, T. L. Inorg. Chem. 1992, 31, 1286.
(22) Luo, L.; Nolan, S. P. Organometallics 1993, 12, 4305.
(23) J ohnson, T. J .; Folting, K.; Streib, W. E.; Martin, J . D.; Huffman,
J . C.; J ackson, S. A.; Eisenstein, O.; Caulton, K. G. Inorg. Chem. 1995,
34, 488.

3850 Organometallics, Vol. 18, No. 19, 1999
Ru¨ba et al.
Sch em e 3
Sch em e 4
F igu r e 5. Structural view of [RuCp(η2-CH2dCHCH2NEt3)-
(PPh3)Br]PF6‚CH2Cl2 (9‚CH2Cl2) showing 20% thermal
-
ellipsoids (PF6 and CH2Cl2 omitted for clarity). Selected
bond lengths (Å) and angles (deg): Ru(1)-C(1-5)av
)
2.216(3), Ru-P(1) ) 2.315(1), Ru-Br ) 2.565(1), Ru-
C(24) ) 2.172(3), Ru-C(25) ) 2.193(3), C(1)-C(2) )
1.403(5), C(2)-C(3) ) 1.380(6), C(3)-C(4) ) 1.425(5), C(4)-
C(5) ) 1.385(5), C(1)-C(5) ) 1.403(5), C(24)-C(25) )
1.392(4); C(24)-Ru-C(25) ) 37.2(1), C(24)-Ru-P(1) )
98.5(1), C(25)-Ru-P(1) ) 85.2(1).
Con clu sion s
the Cp carbon atoms give rise to doublets between 94.5
and 92.9 ppm (cf 77.1, 76.0, and 75.6 ppm in 2a -c). The
downfield chemical shifts are indicative of the higher
oxidation state of the Ru center.
The complexes [RuCp(PR3)(CH3CN)2]PF6 are intrigu-
ing compounds because of versatile reactivity patterns
under mild conditions with respect to substitution and
oxidative addition reactions. Furthermore, preliminary
studies reveal that (i) these complexes promote C-C
coupling of acetylenes to give allyl carbene complexes
capable of C-H activation of alkyl groups and (ii) they
are able to efficiently catalyze the redox isomerization
of allyl alcohols. These studies will be described in
future contributions.
As concerns the reactivity toward nucleophiles, 8a has
been treated with stoichiometric amounts of NEt3,
giving the olefin complex [RuCp(η2-CH2dCHCH2NEt3)-
(PPh3)Br]PF6 (9) in 83% yield (Scheme 4). Apart from
a full NMR spectroscopic and analytical characteriza-
tion, the solid-state structure of 9‚CH2Cl2 has been
determined by single-crystal X-ray diffraction. A struc-
tural view is depicted in Figure 5 with selected bond
distances and angles reported in the captions. Thus, 9‚
CH2Cl2 adopts a three-legged piano-stool conformation
with P(1), Br, and the olefin C(24)-C(25) moiety as the
legs. The olefin moiety of the CH2dCHCH2NEt3 ligand
is bonded slightly asymmetrically to the metal center
with the Ru bonds to the terminal and internal carbon
atoms C(24) and C(25) being 2.172(3) and 2.193(3) Å,
respectively. The C(24)-C(25) distance is 1.392(4) Å.
The Ru-P(1) and Ru-Br distances are 2.315(1) and
2.565(1) Å, respectively.
Ack n ow led gm en t. Financial support by the “Fonds
zur Fo¨rderung der wissenschaftlichen Forschung” is
gratefully acknowledged (Project No. 11896).
Su p p or tin g In for m a tion Ava ila ble: Listings of atomic
coordinates, anisotropic temperature factors, bond lengths and
angles, and least-squares planes for 2b, 2c, and 9‚CH2Cl2
(Tables S1-S15) and kinetic data (Tables S16-S20), including
the conditions and all of the measured rate constants. This
material is available free of charge via the Internet at
http://pubs.acs.org.
OM990245O