Molybdenum and tungsten cyclopentadienone complexes. 1. Synthesis and characterization

Article abstract of DOI:10.1021/om950618v

The labile complexes M(CO)₃(CH₃CN)₃ (M = M₀, W) undergo facile oxidative addition reactions with 4-bromo-2-cyclopentenone to give M(η³-C₅H₅O)(CO)₂(CH ₃CN)₂Br 1a and 2. Complex 1a crystallizes in space group P2₁/m (No. 11) with a = 8.631 (2) A?, b = 12.852 (3) A?, c = 6.659 (2) A?, β = 109.27 (1)°, V = 697.3 (3) A?³, and Z = 2. The structure was refined to R(F) = 0.023 (F ≥ 4σF). 1 and 2 react with potassium tris(pyrazolyl)borate (K[HBpZ₃]), 2,2′-bipyridyl (bipy), and bis(diphenylphosphino)methane (dppm) to give neutral η³-cyclopentenoyl complexes of types M(η³-C₅H₅O)(CO)₂(HBpZ ₃) 3a and 4, M(η³-C₅H₅O)(CO)₂(bipy)-Br 5 and 6, and M(η³-C₅H₅O)(CO)₂(dppm)Br 7 and 8, respectively, in high yields. Single crystal structural studies have been carried out for complexes 3a, 4, and 8. 3a crystallizes in space group Pbca (No. 61) with a = 19.819 (3) A?, b = 13.899 (3) A?, c = 13.088 (2) A?, V = 3605 (1) A?³, and Z = 8, and the structure was refined to R(F) = 0.026 (F ≥ 4σF). 4 is isostructural with 3a and crystallizes in space group Pbca (No. 61) with a = 19.726 (6) A?, b = 13.924 (6) A?, c = 13.080 (4) A?, V = 3593 (2) A?³, and Z = 8, and the structure was refined to R(F) = 0.028 (F ≥ 4σF). 8 crystallizes in space group P1 (No. 2) with a = 10.143 (3) A?, b = 10.972 (4) A?, c = 13.708 (5) A?, α = 82.52 (2)°, β = 85.07 (2)° , γ= 84.77 (1)°, V = 1502.0 (9) A?³, and Z = 2. The structure was refined to R(F) = 0.029 (F ≥ 4σF). Treatment of complexes 3-8 with Ph₃C⁺PF₆^- in methylene chloride solution led to facile hydride abstraction and formation of the stable cationic η⁴-cyclopentadienone complexes [M(η⁴-C₅H₄O)(CO)₂ (HBpz₃)]PF₆ 9a and 10, [M(η₄-C₅H₄O)(CO) ₂(bipy)Br]PF₆ 11 and 12, and [W(η⁴-C₅H₄O)(CO) ₂(dppm)Br]PF₆ (13). Complex 10 has been found to crystallize in space group Pcab (No. 61) with a = 18.242 (4) A?, b = 17.145 (4) A?, c = 13.188 (3) A, V = 4125 (2) A?³, and Z = 8. The structure was refined to R(F) = 0.029 (F ≥ 4σF). 13 crystallizes in space group P2₁/n (No. 14) with a = 11.796 (3) A?, b = 17.512 (7) A?, c = 17.210 (5) A?, β= 93.67 (1)°, V = 3548 (2) A?³, and Z = 4. The structure was refined to R(F) = 0.040 (F ≥ 4σF).

Full text of DOI:10.1021/om950618v

Organometallics 1996, 15, 181-188
181
Molybd en u m a n d Tu n gsten Cyclop en ta d ien on e
Com p lexes. 1. Syn th esis a n d Ch a r a cter iza tion
Klaus Mauthner,1a Christian Slugovc,1a Kurt Mereiter,1b Roland Schmid,1a and
Karl Kirchner*,1a
Institute of Inorganic Chemistry and Institute of Mineralogy, Crystallography, and Structural
Chemistry, Technical University of Vienna, Getreidemarkt 9, A-1060 Vienna, Austria
Received August 8, 1995X
The labile complexes M(CO)3(CH3CN)3 (M ) Mo, W) undergo facile oxidative addition
reactions with 4-bromo-2-cyclopentenone to give M(η3-C5H5O)(CO)2(CH3CN)2Br 1a and 2.
Complex 1a crystallizes in space group P21/m (No. 11) with a ) 8.631 (2) Å, b ) 12.852 (3)
Å, c ) 6.659 (2) Å, â ) 109.27 (1)°, V ) 697.3 (3) Å3, and Z ) 2. The structure was refined
to R(F) ) 0.023 (F g 4σF). 1 and 2 react with potassium tris(pyrazolyl)borate (K[HBpz3]),
2,2′-bipyridyl (bipy), and bis(diphenylphosphino)methane (dppm) to give neutral η3-cyclo-
pentenoyl complexes of types M(η3-C5H5O)(CO)2(HBpz3) 3a and 4, M(η3-C5H5O)(CO)2(bipy)-
Br 5 and 6, and M(η3-C5H5O)(CO)2(dppm)Br 7 and 8, respectively, in high yields. Single
crystal structural studies have been carried out for complexes 3a , 4, and 8. 3a crystallizes
in space group Pbca (No. 61) with a ) 19.819 (3) Å, b ) 13.899 (3) Å, c ) 13.088 (2) Å, V )
3605 (1) Å3, and Z ) 8, and the structure was refined to R(F) ) 0.026 (F g 4σF). 4 is
isostructural with 3a and crystallizes in space group Pbca (No. 61) with a ) 19.726 (6) Å, b
) 13.924 (6) Å, c ) 13.080 (4) Å, V ) 3593 (2) Å3, and Z ) 8, and the structure was refined
to R(F) ) 0.028 (F g 4σF). 8 crystallizes in space group P1h (No. 2) with a ) 10.143 (3) Å,
b ) 10.972 (4) Å, c ) 13.708 (5) Å, R ) 82.52 (2)°, â ) 85.07 (2)° , γ ) 84.77 (1)°, V ) 1502.0
(9) Å3, and Z ) 2. The structure was refined to R(F) ) 0.029 (F g 4σF). Treatment of
complexes 3-8 with Ph3C+PF6 in methylene chloride solution led to facile hydride
-
abstraction and formation of the stable cationic η4-cyclopentadienone complexes [M(η4-
C5H4O)(CO)2 (HBpz3)]PF6 9a and 10, [M(η4-C5H4O)(CO)2(bipy)Br]PF6 11 and 12, and [W(η4-
C5H4O)(CO)2(dppm)Br]PF6 (13). Complex 10 has been found to crystallize in space group
Pcab (No. 61) with a ) 18.242 (4) Å, b ) 17.145 (4) Å, c ) 13.188 (3) Å, V ) 4125 (2) Å3, and
Z ) 8. The structure was refined to R(F) ) 0.029 (F g 4σF). 13 crystallizes in space group
P21/n (No. 14) with a ) 11.796 (3) Å, b ) 17.512 (7) Å, c ) 17.210 (5) Å, â ) 93.67 (1)°, V )
3548 (2) Å3, and Z ) 4. The structure was refined to R(F) ) 0.040 (F g 4σF).
In tr od u ction
As the first part of our study, we report on the
syntheses and characterization of [M(η4-C5H4O)(CO)2-
(HBpz3)]+, [M(η4-C5H4O)(CO)2(bipy)Br]+ (M ) Mo, W),
and [W(η4-C5H4O) (CO)2(dppm)Br]+ and their respective
molybdenum and tungsten η3-cyclopentenoyl precursor
complexes. X-ray structure determinations of repre-
sentative complexes are presented.
Cyclopentadienone (C5H4O) is a rare but, neverthe-
less, interesting and useful π-ligand in transition metal
complexes as previously shown.2,3 In an attempt to
further elaborate the organometallic chemistry of this
ligand, we have undertaken the study of molybdenum
and tungsten cyclopentadienone complexes. While with
respect to diene functionalization reactions the use of
cyclopentadienyl-based molybdenum diene intermedi-
ates has been explored in recent years (in one example
also with diene ) cyclopentadienone3),4 other metal-
ligand sets such as molybdenum tris(pyrazolyl)borate
(HBpz3), 2,2′-bipyridyl (bipy), or bis(diphenylphosphino)-
methane (dppm) have received relatively little attention.
Moreover, there are no reports on the synthesis and
reactivity of tungsten cyclopentadienone complexes in
the literature.
Exp er im en ta l Section
Gen er a l In for m a tion . Manipulations were performed
under an inert atmosphere of nitrogen by using standard
Schlenk techniques and/or a glovebox. All chemicals were
standard reagent grade and used without further purification.
The solvents were purified according to standard procedures.5
The deuterated solvents were purchased from Aldrich and
dried over 4 Å molecular sieves. Mo(η3-C5H5O)(CO)2(CH3-
CN)2Br (1a ),3 Mo(η3-C5H4O-Me)(CO)2(CH3CN)2Br (1b),3 and
(4) (a) Rubio, A.; Liebeskind, L. S. J . Am. Chem. Soc. 1993, 115,
891. (b) Hansson, S.; Miller, J . F.; Liebeskind, L. S. J . Am. Chem. Soc.
1990, 112, 9660. (c) Pearson, A. J .; Mallik, S.; Pinkerton, A. A.; Adams,
J . P.; Zheng, S. J . Org. Chem. 1992, 57, 2910. (d) Pearson, A. J .; Mallik,
S.; Mortezaei, R.; Perry, M. W. D.; Shively, R. J ., J r.; Youngs, W. J . J .
Am. Chem. Soc. 1990, 112, 8034. (e) Pearson, A. J .; Blystone, S. L.;
Nar, H.; Pinkerton, A. A.; Roden, B. A.; Yoon, J . J . Am. Chem. Soc.
1989, 111, 134. (f) Pearson, A. J .; Khan, M. N. I.; Clardy, J . C.; Ciu-
Heng, H. J . Am. Chem. Soc. 1985, 107, 2748. (g) Faller, J . W.; Murray,
H. H.; White, D. L.; Chao, K. H. Organometallics 1983, 2, 400.
(5) Perrin, D. D.; Armarego, W. L. F. Purification of Laboratory
Chemicals, 3rd ed.; Pergamon: New York, 1988.
X Abstract published in Advance ACS Abstracts, November 15, 1995.
(1) (a) Institute of Inorganic Chemistry; (b) Institute of Mineralogy,
Crystallography, and Structural Chemistry.
(2) (a) Kirchner, K.; Mereiter, K.; Schmid, R.; Taube, H. Inorg. Chem.
1993, 32, 5553. (b) Kirchner, K.; Mereiter, K.; Umfahrer, A.; Schmid,
R. Organometallics 1994, 13, 1886. (c) Mauthner, K.; Mereiter, K.;
Schmid, R.; Kirchner, K. Organometallics 1994, 13, 5054.
(3) Liebeskind, L. S.; Bombrun, A. J . Am. Chem. Soc. 1991, 113,
8736.
0276-7333/96/2315-0181$12.00/0 © 1996 American Chemical Society

182 Organometallics, Vol. 15, No. 1, 1996
Mauthner et al.
K[HBpz3]6 were prepared by literature methods. Infrared
spectra were recorded on a Perkin-Elmer 16PC FT IR spec-
trometer. 1H and 13C{1H} NMR spectra were recorded on a
Bruker AC 250 spectrometer operating at 250.13 and 62.86
MHz, respectively, and were referenced to residual solvent
protons. Microanalyses were carried out by the Microanalyti-
cal Laboratories, University of Vienna.
under vacuum. Yield: 5.76
g
(97%). Anal. Calcd for
C17H13BrMoN2O3: C, 43.52; H, 2.79; N, 5.97; Br, 17.03.
Found: C, 43.48; H, 2.82; N, 5.89; Br, 17.66. 1H NMR (δ,
dmso-d6, 20 °C): 8.68 (m, 4H, bipy), 8.22 (dd, 2H), bipy), 7.61
(dd, 2H, bipy), 4.51 (m, 1H), 4.25 (m, 1H), 4.03 (m, 1H), 3.02
(d, 1H, J ) 18.6 Hz), 2.14 (d, 1H, J ) 18.6 Hz). IR
(poly(chlorotrifluoroethylene), cm-1): 1955 (s, νCO), 1871 (s,
Syn th esis. W(η3-C5H5O)(CO)2(CH3CN)2Br (2). This com-
plex has been prepared by following the published procedure
for the analogous molybdenum complexes 1 utilizing W(CO)6
as starting material.3 Complex 2 was isolated as a mixture
of exo and endo conformers in a ratio of about 1:1. Yield: 56%.
Anal. Calcd for C11H11BrN2O3W: C, 27.36; H, 2.30; Br, 16.54;
N, 5.80. Found: C, 27.23; H, 2.36; Br, 16.23; N, 5.92. 1H NMR
(δ, dmso-d6, 20 °C): 4.34 (dd, 1H, J ) 17.0, 2.6 Hz), 3.93 (m,
1H), 3.88 (m, 1H), 3.75-3.68 (m, 1H), 2.33 (d, 1H, J ) 17.0
Hz), 2.07 (s, 6H), 4.38 (dd, 1H, J ) 17.4, 2.7 Hz), 3.93 (m, 1H),
3.88 (m, 1H), 3.75-3.68 (m, 1H), 2.38 (d, 1H, J ) 17.4 Hz),
2.07 (s, 6H). 13C{1H} NMR (δ, dmso-d6, 20 °C): 219.2 (CO),
218.3 (CO), 201.4 (ketonic CO), 76.9, 64.0, 60.0, 41.5, 1.2 (Me),
220.0 (CO), 219.1 (CO), 198.2 (ketonic CO), 78.0, 62.5, 56.5,
42.6, 1.2 (Me).
Mo(η3-C5H5O)(CO)2(HBp z3) (3a ). 1a (1.00 g, 2.53 mmol)
and K[HBpz3] (0.64 g, 2.53 mmol) were dissolved in CH2Cl2
(10 mL), and the mixture was stirred for 12 h at room
temperature. The resulting precipitate of KBr was removed
by filtration, and the solvent was removed under vacuum. The
remaining air-stable yellow solid was collected on a glass frit,
washed with a small amount of acetone (1 mL) and anhydrous
diethyl ether, and dried in vacuo. Yield: 1.1 g (97%). Anal.
ν
CO), 1697 (s, νCdO).
W(η3-C5H5O)(bip y)(CO)2Br (6). A suspension of W(CO)6
(5.0 g, 14.21 mmol) in CH3CN (100 mL) was refluxed for 6
days. The resulting yellow solution was treated at 40 °C with
4-bromo-2-cyclopentenone (about 5-fold excess) in 10 mL of
CCl4. The mixture was stirred for 30 min whereupon bipy (3.3
g, 21.13 mmol) in 10 mL of CH2Cl2 was added and stirred for
additional 30 min. The solvent was evaporated, and the
residue was dissolved in 20 mL of CH3CN. On addition of
diethyl ether, a red microcrystalline precipitate was formed
which was collected on a glass frit, washed with diethyl ether,
and dried under vacuum. Yield: 7.30 g (92%). Anal. Calcd
for C17H11BrN2O3W: C, 36.65; H, 2.35; N, 5.05; Br, 14.34.
Found: C, 36.52; H, 2.22; N, 5.11; Br, 14.16. 1H NMR (δ, CD3-
CN, 20 °C): 8.78 (m, 2H, bipy), 8.45 (d, 2H, bipy), 8.17 (dd,
2H, bipy), 7.56 (dd, 2H, bipy), 4.62 (d, 1H, J ) 17.0 Hz), 3.84
(m, 1H), 3.76 (m, 1H), 3.53 (m, 1H), 2.86 (d, 1H, J ) 17.0 Hz).
IR (poly(chlorotrifluoroethylene), cm-1): 1952 (s, νCO), 1862 (s,
νCO), 1694 (s, νCdO).
Mo(η3-C5H5O)(d p p m )(CO)2Br (7). To a suspension of 1a
(5.0 g, 12.66 mmol) in CH2Cl2 (15 mL) was added dppm (5.35
g, 13.92 mmol), and the mixture was stirred for 1 h at room
temperature. Then diethyl ether (20 mL) was added, and the
resulting precipitate was collected on a glass frit, washed
anhydrous diethyl ether, and dried under vacuum. Yield: 8.38
g (95%). Anal. Calcd for C32H27BrO3MoP2: C, 55.12; H, 3.90;
Br, 11.46. Found: C, 55.52; H, 3.87; Br, 11.26. 1H NMR (δ,
dmso-d6, 20 °C): 7.90-7.00 (m, 20H), 4.90-4.40 (m, 2H), 4.71
(m, 2H), 4.16 (m, 1H), 2.94 (d, 1H, J ) 17.6 Hz), 1.78 (d, 1H,
J ) 17.6 Hz). IR (poly(chlorotrifluoroethylene), cm-1): 1992
(s, νCO), 1957 (s, νCO), 1890 (s, νCO), 1869(s, νCO), 1687 (s, νCdO).
W(η3-C5H5O)(d p p m )(CO)2Br (8). This complex was syn-
thesized analogously to 6 with dppm as starting material.
Yield: 60%. Anal. Calcd for C32H27BrO3P2W: C, 48.95; H,
3.47; Br, 10.18. Found: C, 48.52; H, 3.51; Br, 10.52. 1H NMR
(δ, CD2Cl2, 20 °C): 7.80-7.10 (m, 20H, dppm), 4.85 (m, 2H),
4.40-3.70 (m, 2H, dppm), 4.08 (d, 1H, J ) 17.4 Hz), 2.81 (d,
1H, J ) 17.4 Hz). IR (poly(chlorotrifluoroethylene), cm-1):
1982 (s, νCO), 1952 (s, νCO), 1881 (s, νCO), 1863 (s, νCO), 1689 (s,
Calcd for
C
16H15BMoN6O3: C, 43.08; H, 3.39; N,18.84.
Found: C, 43.01; H, 3.37; N, 18.90. 1H NMR (δ, CD3NO2, 20
°C): 8.64 (d, 1H, HBpz3), 7.88-7.75 (m, 5H, HBpz3), 6.44 (dd,
1H, HBpz3), 6.32-6.29 (m, 2H, HBpz3), 4.91 (dd, 1H), 4.75 (m,
1H), 4.51 (dd, 1H), 3.15 (dd, 1H), 2.28 (d, 1H, J ) 18.0 Hz).
13C{1H} NMR (δ, CD3NO2, 20 °C): 213.0 (CO), 209.8 (CO),
203.14 (ketonic CO), 148.9, 145.3, 143.2, 138.2, 138.0, 136.9,
108.0, 107.3, 107.2, 84.4, 73.8, 69.1, 43.42. IR (poly(chlorot-
rifluoroethylene), cm-1): 1958 (s, νCO), 1861 (s, νCO), 1700 (s,
ν
CdO).
Mo(η3-C5H4O-Me)(CO)2(HBp z3) (3b). This compound was
synthesized analogously to 3a with complex 1b as starting
material. Yield: 4.61g (93%). Anal. Calcd for 17H17
C
-
BMoN6O3: C, 44.38; H, 3.72; N, 18.27. Found: C, 44.41; H,
3.80; N, 18.17. 1H NMR (δ, CDCl3, 20 °C): 8.46 (d, 1H, HBpz3),
7.66-7.59 (m, 4H, HBpz3), 6.27 (dd, 1H, HBpz3), 6.25 (dd, 1H,
HBpz3), 6.18 (dd, 1H, HBpz3), 5.02 (d, 1H, J ) 5.0 Hz), 4.17
(dd, 1H, J ) 5.0, 2.8 Hz), 3.27 (dd, 1H, J ) 17.7, 2.8 Hz), 2.54
(d, 1H, J ) 17.7 Hz). 13C{1H} NMR (δ, CDCl3, 20 °C): 230.7,
222.6 (CO), 201.3 (ketonic CO), 147.5, 146.3, 141.0, 137.7,
136.7, 135.1, 106.7, 106.6, 106.2, 91.3, 89.8, 58.1, 44.7, 15,1
(Me).
W(η3-C5H5O)(CO)2(HBp z3) (4). This complex was synthe-
sized analogously to 3 with 2 as starting material. Yield: 3.60
g (81%). Anal. Calcd for C16H15BN6O3W: C, 35.99; H, 2.83;
N,15.74. Found: C, 35.58; H, 2.78; N, 15.49. 1H NMR (δ,
acetone-d6, 20 °C): 8.70 (d, 1H, HBpz3), 8.16 (d, 1H, HBpz3),
8.07 (d, 1H, HBpz3), 7.87 (m, 3H, HBpz3), 6.48 (dd, 1H, HBpz3),
6.42 (m, 2H, HBpz3), 4.65 (dd, 1H, J ) 17.3, 2.6 Hz), 4.53 (dd,
1H), 4.47 (m, 1H), 4.10 (dd, 1H), 2.84 (d, 1H, J ) 17.3 Hz).
13C{1H} NMR (δ, CD3NO2, 20 °C): 226.5 (CO), 220.3 (CO),
204.6 (ketonic CO), 150.1, 146.0, 143.6, 138.4, 138.1, 137.2,
108.6, 107.6, 107.6, 75.3, 66.6, 59.7, 43.6. IR (poly(chlorotri-
fluoroethylene), cm-1): 1950 (s, νCO), 1846 (s, νCO), 1698 (s,
νCdO).
[Mo(η4-C5H4O)(CO)2(HBp z3)]P F 6 (9a ). A solution of 3a
-
(347 mg, 0.778 mmol) in CH2Cl2 was treated with Ph3C+PF6
(302 mg, 0.778 mmol) and was stirred for 3 h at room
temperature. The yellow solid that separated from solution
was collected on a glass frit, washed with CH2Cl2 (1 mL) and
anhydrous diethyl ether, and dried under vacuum. Yield: 330
mg (72%). Anal. Calcd for C16H14BF6MoN6O3P: C, 32.57; H,
2.39; N,14.24. Found: C, 32.39; H, 2.40; N, 14.19. 1H NMR
(δ, CD3CN, 20 °C): 8.28 (d, 1H, HBpz3), 8.01 (m, 3H, HBpz3),
7.77 (d, 2H, HBpz3), 6.63 (dd, 2H, Hâ), 6.53 (dd, 1H, HBpz3),
6.45 (m, 2H, HBpz3), 4.73 (dd, 2H, HR). 13C{1H} NMR (δ, CD3-
CN, 20 °C): 205.1 (CO), 176.0 (ketonic CO), 148.1 (2C, HBpz3),
147.0 (HBpz3), 140.2 (3C, HBpz3), 109.0 (3C, HBpz3), 89.6 (Câ),
89.5 (CR). IR (poly(chlorotrifluoroethylene), cm-1): 2110 (s,
νCO), 2052 (s, νCO), 1685 (s, νCdO).
[Mo(η4-C5H3O-2-Me)(CO)2(HBp z3)]P F 6 (9b). This com-
ν
CdO).
pound was synthesized analogously to 9a but with 3b as
starting material. Yield: 2.23 g (82%). Anal. Calcd for
Mo(η3-C5H5O)(bip y)(CO)2Br (5). To a suspension of 1a
(5.0 g, 12.66 mmol) in CH3CN (10 mL) was added bipy (2.4 g,
15.37 mmol), and the mixture was stirred for 1 h at room
temperature. The resulting precipitate was collected on a
glass frit, washed with anhydrous diethyl ether, and dried
C
17H16BF6MoN6O3P: C, 33.80; H, 2.67; N,13.91. Found: C,
33.86; H, 2.70; N, 14.01. 1H NMR (δ, CD3CN, 20 °C): 8.21 (d,
1H, HBpz3), 8.02-7.75 (m, 5H, HBpz3), 6.80 (dd, 1H, Hâ), 6.49-
6.44 (m, 3H, HBpz3), 6.24 (dd, 1H, Hâ), 4.90 (dd, 1H, HR), 1.21
(s, 3H, Me). 13C{1H} NMR (δ, CD3CN, 20 °C): 207.1, 207.0
(CO), 177.4 (ketonic CO), 149.4, 149.2, 147.4, 141.4, 141.3,
(6) Trofimenko, S. Inorg. Synth. 1970, 12, 99.

Mo and W Cyclopentadienone Complexes
Organometallics, Vol. 15, No. 1, 1996 183
Ta ble 1. Cr ysta llogr a p h ic Da ta
1a
3a
4
8
10
13‚CH3CN
formula
fw
C
11H11BrMoN2O3
C16H15BMoN6O3
446.09
C16H15BN6O3W
534.00
C32H27BrO3P2W
785.24
C16H14BF6N6O3PW C34H29BrF6NO3P3W
395.07
677.96
970.25
cryst size, mm
space group
a, Å
b, Å
c, Å
R, deg
â, deg
γ, deg
V, Å3
0.18 × 0.25 × 0.36 0.23 × 0.25 × 0.38 0.07 × 0.22 × 0.29 0.21 × 0.27 × 0.44 0.11 × 0.2 × 0.65
0.18 × 0.24 × 0.48
P21/n (No. 14)
11.796(3)
17.512(7)
17.210(5)
P21/m (No. 11)
8.631(2)
Pbca (No. 61)
19.819(3)
Pbca (No. 61)
19.726(6)
P1h (No. 2)
10.143(3)
10.972(4)
13.708(5)
82.52(2)
85.07(2)
84.77(1)
1502.0(9)
2
Pcab (No. 61)
18.242(4)
12.852(3)
6.659(2)
13.899(3)
13.088(2)
13.924(6)
13.080(4)
17.145(4)
13.188(3)
109.27(1)
93.67(1)
697.3(3)
2
3605(1)
8
3593(2)
8
4125(2)
8
3548(2)
4
1.816
295
4.585
Z
F
T, K
calc, g cm-3
1.882
1.644
1.975
1.736
2.184
297
295
295
297
296
µ, mm-1 (Mo KR)
absorption corr.
transmiss. fact.,
min/max
3.806
0.758
6.461
5.313
5.767
analytical
0.64/0.82
analytical
0.85/0.89
analytical
0.29/0.63
analytical
0.34/0.57
analytical
0.38/0.59
empirical
0.92/1.14
θ
max, deg
index ranges
27
25
25
25
25
24
-11 e h e 10
0 e k e 16
0 e l e 8
1713
0 e h e 23
0 e k e 16
0 e l e 13
3105
0 e h e 23
0 e k e 16
0 e l e 15
4200
-11 e h e 12
0 e k e 13
-15 e l e 16
5288
0 e h e 21
0 e k e 20
0 e l e 15
3645
0 e h e 13
0 e k e 20
-19 e l e 19
5614
no. of rflns
measd
no. of unique rflns 1591
3105
2417
3158
2222
5288
4684
3645
2659
5614
4214
no. of rflns F >
1370
4σ(F)
no. of params
R(F)(F > 4σ(F))
R(F)(all data)
wR(F2)(all data)
diff Fourier
peaks
107
264
255
358
323
444
0.0229
0.0314
0.0505
-0.42/0.28
0.0261
0.0427
0.0550
-0.26/0.21
0.0276
0.0534
0.05559
-0.50/0.43
0.0288
0.0361
0.0691
-1.05/1.09
0.0285
0.0533
0.0521
-0.48/0.49
0.0397
0.0653
0.0949
-0.63/0.93
min/max, eÅ-3
140.8, 121.1 (Câ), 110.0, 109.6, 109.5, 94.6 (Câ), 84.4 (CR), 77.7
(CR), 12.1 (Me).
a pale red compound precipitated which was collected on a
glass frit, washed with diethyl ether, and dried under vacuum.
Yield: 2.7 g. 1H NMR (δ, CD3CN, 20 °C): 7.84-7.19 (m, 20H,
dppm), 5.12 (m, 1H), 5.00 (m, 1H), 4.60 (m, 1H), 4.20 (m, 2H),
3.71 (m, 1H). IR (poly(chlorotrifluoroethylene), cm-1): 1964
(s, νCO), 1894 (s, νCO).
[W(η4-C5H4O)(CO)2(HBp z3)]P F 6 (10). This compound was
synthesized analogously to 9 with complex 4 as starting
material. Yield: 1.71 g (80%). Anal. Calcd for C16H14BF6-
N6O3PW: C, 28.35; H, 2.08; B, 1.59; N, 12.40. Found: C, 28.41;
H, 2.05; N, 12.36. 1H NMR (δ, acetone-d6, 20 °C): 8.83 (d,
1H, HBpz3), 8.32 (d, 1H, HBpz3), 8.23 (m, 4H, HBpz3), 6.91
(m, 2H, Hâ), 6.72 (dd, 1H, HBpz3), 6.58 (m, 2H, HBpz3), 4.59
(m, 2H, HR). 13C{1H} NMR (δ, acetone-d6, 20 °C): 196.9 (CO),
174.5 (ketonic CO), 148.9 (HBpz3), 147.8 (2C, HBpz3), 140.7
(2C, HBpz3), 140.3 (HBpz3), 109.8 (HBpz3), 109.5 (2C, HBpz3),
83.2 (Câ), 81.4 (CR). IR (poly(chlorotrifluoroethylene), cm-1):
2096 (s, νCO), 2032 (s, νCO), 1680 (s, νCdO).
[W(η4-C5H4O)(d p p m )(CO)2Br ]P F 6 (13). This complex was
synthesized analogously to 11 with 8 as starting material.
Yield: 90%. Anal. Calcd for C32H26BrF6O3P3W: C, 38.09; H,
2.60; Br, 15.84; P, 9.20. Found: C, 38.13; H, 2.53; Br, 16.14;
P, 9.47. 1H NMR (δ, CD3NO2, 20 °C): 8.00-7.30 (m, 20H,
dppm), 5.94 (m, 1H), 5.89 (m, 1H), 5.60-5.40 (m, 2H), 4.60
(m, 1H), 4.53 (m, 1H). 13C{1H} NMR (δ, CD3CN, 20 °C): 191.3
(CO), 191.2 (CO), 173.8 (CdO), 134-127 (C6H5), 89.2, 87.2,
80.1, 73.2, 38.0 (PCH2P). IR (poly(chlorotrifluoroethylene),
cm-1): 2070 (s, νCO), 2033 (s, νCO), 1671 (s, νCdO).
[Mo(η4-C5H4O)(bip y)(CO)2Br ]P F 6 (11). This complex was
synthesized analogously to 9 except that complex 5 was
utilized as starting material and the reaction time was 24 h.
Yield: 330 mg (72%). Anal. Calcd for C17H12BrF6MoN2O3P:
C, 33.30; H, 1.97; N, 4.57. Found: C, 33.52; H, 1.82; N, 4.66.
1H NMR (δ, CD3CN, 20 °C): 8.75 (d, 2H, bipy), 8.55 (d, 2H,
bipy), 8.33 (dd, 2H, bipy), 7.76 (dd, 2H, bipy), 6.46 (m, 2Hâ),
4.64 (m, 2HR). 13C{1H} NMR (δ, CD3NO2, 20 °C): 203.7 (CO),
174.9 (CdO), 155.5 (bipy), 155.0 (bipy), 143.1 (bipy), 129.9
(bipy), 126.1 (bipy), 89.5 (Câ), 86.9 (CR). IR (poly(chlorotrif-
luoroethylene), cm-1): 2096 (s, νCO), 2040 (s, νCO), 1688 (s, νCdO).
[W(η4-C5H4O)(bip y)(CO)2Br ]P F 6 (12). This complex was
synthesized analogously to 11 with 6 used as starting material.
Yield: 97%. Anal. Calcd for C17H12BrF6N2O3PW: C, 29.13;
H, 1.73; N, 4.00; Br, 11.40. Found: C, 30.52; H, 1.82; N, 3.89;
Br, 11.58. 1H NMR (δ, CD3NO2, 20 °C): 9.06 (d, 2H, bipy),
8.69 (d, 2H, bipy), 8.49 (dd, 2H, bipy), 7.90 (dd, 2H, bipy), 6.28
(m, 2Hâ), 4.32 (m, 2HR). 13C{1H} NMR (δ, CD3NO2, 20 °C):
194.7 (CO), 172.4 (CdO), 156.4 (bipy), 156.1 (bipy), 143.9
(bipy), 131.0 (bipy), 126.7 (bipy), 83.5 (Câ), 79.7 (CR). IR (poly-
(chlorotrifluoroethylene), cm-1): 2091 (s, νCO), 2028 (s, νCO),
1667 (s, νCdO).
X-r a y Str u ctu r e Deter m in a tion for 1a , 3a , 4, 6, 10, a n d
13. Crystal data and experimental details are given in Table
1. X-ray data were collected on a Philips PW1100 four-circle
diffractometer using graphite-monochromated Mo KR (λ )
0.710 69 Å) radiation and the θ - 2θ scan technique. Three
representative reference reflections were measured every 120
min and used to correct for crystal decay and system instabil-
ity. Corrections for Lorentz and polarization effects, and for
absorption were applied. The structures were solved by direct
methods.7 All non-hydrogen atoms were refined anisotropi-
cally, and hydrogen atoms were included in idealized posi-
tions.8 The structures were refined against F2. Final posi-
tional parameters are given in Tables 2-7.
Resu lts a n d Discu ssion
Syn th esis a n d Ch a r a cter iza tion of Molybd en u m
a n d Tu n gst en η3-Cyclop en t en oyl Com p lexes.
(7) Hall, S. R.; Flack, H. D.; Stewart, J . M. XTAL3.2. Integrated
system of computer programs for crystal structure determination.
Universities of Western Australia (Australia), Geneva (Switzerland),
and Maryland (USA), 1992.
(8) Sheldrick, G. M. SHELXL93. Program for crystal structure
refinement. University of Go¨ttingen, Go¨ttingen, Germany, 1993.
Attem p ted Syn th esis of [Mo(η4-C5H4O)(d p p m )(CO)2Br ]-
P F 6. Following the protocol for complexes 9-12, a solution
of 7 (3.0 g, 4.3 mmol) in CH2Cl2 was treated with 1 equiv of
Ph3C+PF6- and stirred overnight. On addition of diethyl ether,

184 Organometallics, Vol. 15, No. 1, 1996
Mauthner et al.
Ta ble 2. Atom ic Coor d in a tes a n d Equ iva len t
Isotr op ic Disp la cem en t P a r a m eter s (Å2 ×103) for
Mo(η3-C5H5O)(CO)2(CH3CN)2Br (1a )a
Ta ble 4. Atom ic Coor d in a tes a n d Equ iva len t
Isotr op ic Disp la cem en t P a r a m eter s (Å2 ×103) for
W(η3-C5H5O)(CO)2(HBp z3) (4)
a
x
y
z
Ueq
x
y
z
Ueq
Mo
Br
0.37830(3)
0.09189(4)
0.5664(5)
0.6090(3)
0.7484(4)
0.4481(3)
0.2035(3)
0.1345(3)
0.2581(3)
0.8180(5)
0.4884(2)
0.25000
0.25000
0.2500
0.47029(4)
0.16769(6)
0.7819(6)
0.6878(5)
0.6162(5)
0.2937(4)
0.7090(4)
0.8215(4)
0.6222(3)
0.5667(8)
0.1842(3)
33(1)
54(1)
58(1)
59(1)
67(1)
40(1)
44(1)
55(1)
47(1)
83(1)
58(1)
W
0.14507(1)
0.1709(3)
0.1740(3)
0.2466(4)
0.2829(4)
0.2290(3)
0.2665(5)
0.3401(4)
0.1648(3)
0.1784(2)
0.2283(3)
0.2766(2)
-0.0138(2)
0.0379(2)
0.0094(3)
-0.0591(3)
-0.0723(3)
0.0496(2)
0.1140(2)
0.1460(3)
0.1040(4)
0.0440(4)
0.0299(2)
0.0895(2)
0.1042(3)
0.0552(3)
0.0087(3)
-0.0020(3)
0.16597(2)
0.2127(5)
0.1121(5)
0.0837(7)
0.1680(6)
0.2404(5)
0.0021(10)
0.1740(9)
0.0280(4)
-0.0520(3)
0.1718(4)
0.1733(4)
0.2026(3)
0.1587(3)
0.1179(4)
0.1336(4)
0.1875(4)
0.3362(3)
0.3166(3)
0.4018(4)
0.4741(4)
0.4307(4)
0.1826(3)
0.1398(3)
0.0811(4)
0.0864(4)
0.1504(4)
0.2539(5)
0.16221(2)
0.0086(5)
-0.0008(5)
0.0001(7)
0.0436(6)
0.0646(6)
-0.0055(9)
0.0620(10)
0.1661(5)
0.1732(4)
0.2424(5)
0.2937(4)
0.1517(3)
0.1017(3)
0.0195(4)
0.0174(5)
0.1017(5)
0.2354(3)
0.2026(3)
0.2053(5)
0.2336(4)
0.2512(5)
0.3272(3)
0.3039(3)
0.3815(4)
0.4550(4)
0.4190(4)
0.2522(6)
35(1)
67(2)
63(2)
84(2)
79(2)
75(2)
108(5)
108(5)
49(2)
72(1)
56(2)
102(2)
40(1)
34(1)
45(1)
54(2)
48(2)
43(1)
38(1)
55(2)
59(2)
53(2)
38(1)
35(1)
45(1)
52(2)
46(1)
44(2)
C(1)
C(2)
C(3)
C(4)
C(5)
O(1A)b
O(1B)b
C(6)
O(2)
C(7)
O(3)
N(1)
N(2)
C(8)
C(9)
C(10)
N(3)
N(4)
C(11)
C(12)
C(13)
N(5)
N(6)
C(14)
C(15)
C(16)
B
C(1)
C(2)
C(3)
C(4)
C(5)
C(6)
N
0.1634(2)
0.1917(3)
0.1505(2)
0.0782(2)
0.0045(2)
0.1353(2)
0.1163(4)
0.0957(2)
O(1)b
O(2)
a
b
Ueq
)
1/3∑i∑jUija*a*(aiaj). The cyclopentenoyl moietysC(1),
i
j
C(2), C(3), and O(1)sshows disorder with oxygen O(1) (site
ccupation factor 0.5) alternatively attached to C(3) and its mirror-
symmetric equivalent C(3′) located at x,
1
/ - y, z.
2
Ta ble 3. Atom ic Coor d in a tes a n d Equ iva len t
Isotr op ic Disp la cem en t P a r a m eter s (Å2 ×103) for
Mo(η3-C5H5O)(CO)2(HBp z3) (3a )
a
x
y
z
Ueq
Mo
0.14491(1)
0.1704(2)
0.1733(2)
0.2453(2)
0.2821(2)
0.2278(2)
0.2642(3)
0.3382(2)
0.1646(1)
0.1778(1)
0.2277(2)
0.2751(1)
-0.0135(1)
0.0377(1)
0.0088(2)
-0.0599(2)
-0.0721(1)
0.0500(1)
0.1140(1)
0.1459(2)
0.1036(2)
0.0438(2)
0.0306(1)
0.0904(1)
0.1043(2)
0.0551(2)
0.0094(2)
-0.0006(2)
0.16599(2)
0.2126(3)
0.1126(3)
0.0834(4)
0.1677(3)
0.2406(3)
0.0035(5)
0.1747(5)
0.0281(2)
-0.0522(2)
0.1723(3)
0.1739(2)
0.2030(2)
0.1587(2)
0.1181(2)
0.1349(2)
0.1888(2)
0.3368(2)
0.3175(2)
0.4028(2)
0.4755(2)
0.4321(2)
0.1826(2)
0.1388(2)
0.0800(2)
0.0856(2)
0.1505(2)
0.2555(3)
0.16192(2)
0.0077(3)
-0.0023(3)
-0.0009(3)
0.0427(3)
0.0607(4)
-0.0080(5)
0.0624(5)
0.1649(3)
0.1727(2)
0.2433(3)
0.2930(2)
0.1523(2)
0.1007(2)
0.0198(2)
0.0180(3)
0.1033(2)
0.2349(2)
0.2026(2)
0.2031(2)
0.2332(2)
0.2527(2)
0.3276(2)
0.3041(2)
0.3823(2)
0.4557(2)
0.4190(2)
0.2533(3)
34(1)
72(1)
64(1)
79(1)
82(1)
78(1)
110(3)
113(3)
48(1)
76(1)
58(1)
104(1)
39(1)
36(1)
46(1)
57(1)
49(1)
41(1)
40(1)
53(1)
61(1)
54(1)
39(1)
37(1)
45(1)
52(1)
49(1)
43(1)
C(1)
C(2)
C(3)
C(4)
C(5)
O(1A)b
O(1B)b
C(6)
O(2)
C(7)
O(3)
N(1)
N(2)
C(8)
C(9)
C(10)
N(3)
N(4)
C(11)
C(12)
C(13)
N(5)
N(6)
C(14)
C(15)
C(16)
B
a
b
See footnote in Table 2. The cyclopentenoyl moietysC(1)-
O(1B)sis disordered with the oxygen atom alternatively attached
as O(1A) to C(3) or as O(1B) to C(4). Refined site occupation
factors: 0.49(1) for O(1A) and 0.51(1) for O(1B).
Section). Conversion to complexes Mo(η3-C5H5O)(CO)2-
(HBpz3) (3a ), W(η3-C5H5O)(CO)2(HBpz3) (4), Mo(η3-
C5H5O)(CO)2(bipy)Br (5), and Mo(η3-C5H5O)(CO)2(dppm)-
Br (7) was accomplished by treatment of 1 and 2 with
stoichiometric amounts of K[HBpz3], bipy, and dppm,
respectively, in either CH3NO2 or CH3CN as the sol-
vents in high yields. The synthesis of W(η3-C5H5O)-
(CO)2(bipy)Br (6) and W(η3-C5H5O)(CO)2(dppm)Br (8)
was more conveniently performed as an one-pot proce-
dure directly from W(CO)6; after the carbonyl is refluxed
for 6 days the resulting complex W(CO)3(CH3CN)3 is
treated with 4-bromo-2-cyclopentenone to form complex
2 in situ. Addition of the appropriate chelating ligand
(1 equiv) gave on workup 6 and 8 in 92 and 60% yields.
Compounds 3-8 are all crystalline solids ranging in
color from yellow to orange. They are generally only
sparingly soluble in most common organic solvents and
are air-stable in the solid state and also for extended
periods in solution. 3-8 have been fully characterized
by a combination of elemental analysis and 1H NMR
and IR spectroscopy. Where solubility has permitted
(3 and 4), 13C{1H} NMR spectra have been recorded.
The structures of 1a , 3a , 4, and 8 have been determined
by X-ray crystallography.
a
b
See footnote a of Table 2. The cyclopentenoyl moietysC(1)-
O(1B)sis disordered with the oxygen atom alternatively attached
as O(1A) to C(3) or as O(1B) to C(4). Refined site occupation
factors: 0.525(7) for O(1A) and 0.475(7) for O(1B).
9
9
Mo(CO)3(CH3CN)3 and W(CO)3(CH3CN)3 react with
4-bromo-2-cyclopentenone10 in acetonitrile to afford the
neutral η3-cyclopentenoyl complexes Mo(η3-C5H5O)-
(CO)2(CH3CN)2Br (1a )3 and W(η3-C5H5O)(CO)2(CH3-
CN)2Br (2) in 93 and 56% isolated yields, respectively.
The methyl-substituted derivative, Mo(η3-C5H4O-Me)-
(CO)2(CH3CN)2Br (1b), was prepared in analogous
fashion by utilizing 4-bromo-2-methylcyclopentenone10
The 1H NMR spectra of 3-8 all show the expected
resonances for the cyclopentenoyl moiety giving rise to
three multiplets and two doublets assigned to the allyl
protons and Hanti and Hsyn protons, respectively, and are
consistent with the presence of the coligands HBpz3,
bipy, and dppm. It is interesting to note, however, that
the resonances of the anti protons of all tungsten
complexes are shifted down field by about 1.3 ppm with
respect to the analogous molybdenum complexes (for
comparison, 3 exhibits two apparent doublets centered
1
as starting material. 2 has been characterized by H
and 13C{1H} NMR spectroscopy, and elemental analysis.
The spectroscopic features of 2 are very similar to those
of 1a and will not be discussed here (see Experimental
(9) (a) Tate, D. P.; Knipple, W. R.; Augl, J . M. Inorg. Chem. 1962,
1, 433. (b) Kubas, G. J .; van der Sluys, L. S. Inorg. Synth. 1990, 28,
29.
(10) Depuy, C. H.; Isaaks, M.; Eilers, K. L.; Morris, G. F. J . Org.
Chem. 1964, 20, 3503.

Mo and W Cyclopentadienone Complexes
Organometallics, Vol. 15, No. 1, 1996 185
Ta ble 5. Atom ic Coor d in a tes a n d Equ iva len t
Isotr op ic Disp la cem en t P a r a m eter s (Å2 ×103) for
W(η3-C5H5O)(CO)2(d p p m )Br (8)
Ta ble 6. Atom ic Coor d in a tes a n d Equ iva len t
Isotr op ic Disp la cem en t P a r a m eter s (Å2 ×103) for
[W(η4-C5H4O)(CO)2(HBp z3)]P F 6 (10)a
a
x
y
z
Ueq
x
y
z
Ueq(Uiso)
W
Br
P(1)
P(2)
C(1)
C(2)
C(3)
C(4)
0.50365(2)
0.62104(6)
0.71075(11)
0.70930(11)
0.4159(5)
0.3311(6)
0.2156(7)
0.2452(7)
0.3853(5)
0.1188(6)
0.1530(25)
0.3855(5)
0.3153(5)
0.4376(5)
0.3930(4)
0.8269(4)
0.7655(4)
0.8572(6)
0.8879(7)
0.8273(7)
0.7370(8)
0.7050(6)
0.7444(4)
0.6485(5)
0.6793(6)
0.8068(6)
0.9032(6)
0.8737(5)
0.7282(5)
0.6431(6)
0.6495(8)
0.7378(9)
0.8252(8)
0.8195(6)
0.7697(5)
0.6877(6)
0.7350(7)
0.8644(7)
0.9501(6)
0.9026(5)
0.16810(2)
-0.03737(5)
0.26337(10)
0.13556(10)
0.2056(6)
0.1191(7)
0.1976(10)
0.3307(9)
0.3195(6)
0.1598(7)
0.3595(22)
0.0644(5)
0.0100(5)
0.3003(5)
0.3747(4)
0.1683(4)
0.2470(4)
0.1582(5)
0.1491(6)
0.2279(6)
0.3174(8)
0.3264(6)
0.4208(4)
0.5046(4)
0.6207(5)
0.6534(5)
0.5716(5)
0.4569(5)
0.2476(4)
0.2468(6)
0.3301(8)
0.4174(7)
0.4183(6)
0.3337(5)
-0.0112(4)
-0.1027(5)
-0.2124(6)
-0.2285(6)
-0.1393(5)
-0.0285(5)
0.20410(1)
0.14253(4)
0.11687(8)
0.30241(8)
0.0614(4)
0.1160(5)
0.1588(6)
0.1401(6)
0.1024(4)
0.2027(7)
0.1831(17)
0.3002(4)
0.3539(4)
0.2823(3)
0.3286(3)
0.1963(3)
-0.0115(3)
-0.0404(4)
-0.1408(5)
-0.2093(4)
-0.1822(4)
-0.0832(4)
0.1287(3)
0.1646(4)
0.1790(5)
0.1608(5)
0.1252(5)
0.1088(4)
0.3867(3)
0.4698(4)
0.5352(5)
0.5174(5)
0.4361(5)
0.3702(4)
0.3683(3)
0.3995(4)
0.4517(5)
0.4726(5)
0.4417(4)
0.3886(4)
44(1)
65(1)
41(1)
44(1)
70(2)
83(2)
113(3)
104(2)
73(2)
144(4)
94(9)
70(1)
106(2)
56(1)
80(1)
45(1)
46(1)
75(2)
94(2)
83(2)
102(2)
84(2)
45(1)
58(1)
76(2)
76(2)
77(2)
60(1)
50(1)
80(2)
104(2)
98(2)
88(2)
69(1)
50(1)
71(2)
88(2)
83(2)
74(2)
61(1)
W
O(1)
C(1)
C(2)
C(3)
C(4)
C(5)
N(1)
N(2)
C(6)
C(7)
C(8)
N(3)
N(4)
C(9)
C(10)
C(11)
N(5)
N(6)
C(12)
C(13)
C(14)
B
0.39442(1)
0.2985(2)
0.2989(3)
0.2815(3)
0.2723(3)
0.2997(3)
0.3259(3)
0.5365(2)
0.4667(2)
0.4581(3)
0.5202(4)
0.5682(3)
0.5206(2)
0.4484(2)
0.4272(3)
0.4855(3)
0.5430(3)
0.5627(2)
0.4959(2)
0.5078(3)
0.5813(3)
0.6132(3)
0.5682(3)
0.3822(3)
0.3784(2)
0.3715(3)
0.3635(2)
0.28252(13)
0.3650(3)
0.2024(3)
0.3050(3)
0.2622(4)
0.2617(3)
0.3053(3)
0.3473(7)
0.2073(7)
0.2774(5)
0.3093(8)
0.2454(7)
0.2421(8)
0.3127(8)
0.45307(1)
0.4913(2)
0.4908(4)
0.4285(3)
0.4586(4)
0.5360(4)
0.5511(3)
0.5528(3)
0.5547(2)
0.6264(3)
0.6701(4)
0.6218(3)
0.4470(2)
0.4297(2)
0.3863(3)
0.3762(3)
0.4149(3)
0.4153(3)
0.3985(2)
0.3420(3)
0.3226(3)
0.3700(3)
0.4774(4)
0.4619(3)
0.4691(3)
0.3356(3)
0.2707(2)
0.23486(12)
0.2425(4)
0.2280(6)
0.1572(4)
0.3135(4)
0.1871(5)
0.2770(4)
0.2093(8)
0.2615(9)
0.2354(5)
0.2039(9)
0.2670(8)
0.1552(7)
0.3157(7)
0.28538(2)
0.0438(3)
0.1370(5)
0.2082(5)
0.3061(4)
0.3050(4)
0.2053(4)
0.2539(3)
0.2927(3)
0.3326(5)
0.3175(4)
0.2699(4)
0.1236(3)
0.1391(3)
0.0588(4)
-0.0062(4)
0.0360(4)
0.2952(3)
0.3377(3)
0.4059(4)
0.4085(5)
0.3378(4)
0.2108(5)
0.4381(4)
0.5229(3)
0.2857(4)
0.2798(3)
0.5390(3)
0.4988(5)
0.5839(4)
0.5968(5)
0.4887(7)
0.4444(5)
0.6418(5)
0.4704(9)
0.5834(11)
0.5271(6)
0.6273(10)
0.4265(9)
0.5058(11)
0.5480(12)
32(1)
55(1)
45(1)
46(1)
51(2)
50(2)
48(1)
37(1)
36(1)
49(2)
54(2)
50(2)
36(1)
34(1)
37(1)
43(1)
41(1)
37(1)
36(1)
44(1)
48(2)
48(1)
42(2)
42(1)
66(1)
37(1)
58(1)
38(1)
89(2)
83(2)
102(3)
141(4)
125(4)
118(3)
55(5)
C(5)
O(1A)b
O(1B)b
C(6)
O(2)
C(7)
O(3)
C(8)
C(9)
C(10)
C(11)
C(12)
C(13)
C(14)
C(15)
C(16)
C(17)
C(18)
C(19)
C(20)
C(21)
C(22)
C(23)
C(24)
C(25)
C(26)
C(27)
C(28)
C(29)
C(30)
C(31)
C(32)
C(15)
O(2)
C(16)
O(3)
Pb
F(1)b
F(2)b
F(3)b
F(4)b
F(5)b
F(6)b
F(1A)c
F(2A)c
P(1A)c
F(3A)c
F(4A)c
F(5A)c
F(6A)c
87(11)
101(9)
83(7)
58(5)
67(6)
76(7)
a
b
See footnote in Table 2. The cyclopentenoyl moietysC(1)-
O(1B)sis disordered with the oxygen atom alternatively attached
as O(1A) to C(3) or as O(1B) to C(4). Refined site occupation
factors: 0.79(1) for O(1A) and 0.21(1) for O(1B).
a
b
See Footnote in Table 2. PF6 octahedron orientation disor-
dered with refined site occupation factors 0.77(1). c PF6 octahedron
orientation disordered with refined site occupation factors 1-0.77(1)
) 0.23(1), which were refined isotropically.
at 3.15 and 2.88 ppm whereas 4 shows two apparent
doublets at 4.43 and 2.84 ppm). The 13C{1H} NMR
spectra of 3 and 4 bear no unusual features, with the
characteristic resonance of the ketonic “carbonyl” carbon
observed at 203.1 and 204.6 ppm, respectively. The cis
carbonyl ligands are magnetically inequivalent, giving
rise to resonances at 213.0 and 209.9 ppm, and 226.5
and 204.6 ppm, respectively.
The IR spectra of 3-8 display the two expected peaks
for a cis dicarbonyl structure in the ranges of 1955-
1992 cm-1 and 1861-1890 cm-1, respectively, together
with a peak in the range of 1687-1700 cm-1 due to the
ketonic carbonyl of the cyclopentenoyl ligand.
solution. All complexes have been characterized by IR
1
and H and 13C{1H} NMR spectroscopy and elemental
analyses. Since no tungsten cyclopentadienone com-
plexes are reported in the literature, the structures of
10 and 13 have been determined by X-ray crystal-
lography.
In the IR spectra of 9-13, the stretching frequencies
of the ketonic carbonyl group are observed at 1685,
1680, 1688, 1667, and 1671 cm-1, respectively, consis-
tent with other cyclopentadienone complexes2,3,11 but
slightly lower than are the frequencies for the free
ligand observed at 1727 and 1724 cm-1 12
Thus, as
.
expected, coordination leads to a decrease of the CdO
bond strength by lowering the π-electron density from
this group to the ring and the metal center. In addition,
these complexes exhibit two strong absorptions in the
carbonyl region (in the range of 2070-2110 and 2028-
2052 cm-1, respectively) consistent with a cis disposition
of the two carbonyls and compatible with expectations
for cationic d4 complexes. While the molybdenum
Syn th esis a n d Ch a r a cter iza tion of Molybd en u m
a n d Tu n gsten η4-Cyclop en ta d ien on e Com p lexes.
-
Treatment of 3-8 with Ph3C+ (introduced as the PF6
salt) in CH2Cl2 led to facile hydride abstraction yielding,
with the exception of 7, the cationic cyclopentadienone
complexes 9-13 in 72-97% isolated yields. Surpris-
ingly, in the case of 7 no cyclopentadienone complex,
as shown by 1H NMR and IR spectroscopy, was ob-
tained. Therefore, no attempt was made to further
characterize this compound. Complexes 9-13 are air-
stable in the solid state but decompose readily in
(11) Hoffman, K.; Weiss, E. J . Organomet. Chem. 1977, 128, 237.
(12) Maier, G.; Franz, L. H.; Harten, H.-G.; Lanz, K.; Reisenbauer,
H. P. Chem. Ber. 1985, 118, 3196.

186 Organometallics, Vol. 15, No. 1, 1996
Mauthner et al.
Ta ble 7. Atom ic Coor d in a tes a n d Equ iva len t
Isotr op ic Disp la cem en t P a r a m eter s (Å2 ×103) for
[W(η4-C5H4O)(CO)2(d p p m )Br ]P F 6‚CH3CN
(13‚CH3CN)
a
x
y
z
Ueq
W
Br
P(1)
P(2)
C(1)
C(2)
C(3)
C(4)
C(5)
O(1)
C(6)
O(2)
C(7)
O(3)
C(8)
0.22855(2)
0.39693(6)
0.34454(14) 0.37732(11) 0.31011(10)
0.20998(15) 0.29726(11) 0.40891(11)
0.44581(2)
0.40150(5)
0.40794(2)
0.50328(4)
40(1)
58(1)
42(1)
46(1)
54(2)
60(2)
55(2)
54(2)
52(2)
74(2)
54(2)
76(2)
49(2)
63(2)
51(2)
47(2)
54(2)
65(2)
66(2)
70(2)
62(2)
49(2)
57(2)
89(3)
105(4)
88(3)
72(2)
53(2)
68(2)
88(3)
95(4)
102(4)
71(2)
61(2)
79(3)
110(4)
149(7)
170(7)
108(4)
67(1)
173(4)
234(6)
263(7)
240(7)
154(3)
206(5)
208(12)
259(22)
399(35)
0.1723(6)
0.2914(6)
0.3340(6)
0.2399(7)
0.1422(6)
0.1145(5)
0.1487(6)
0.1078(5)
0.0768(6)
-0.0107(4)
0.3370(6)
0.4917(6)
0.5810(6)
0.6910(6)
0.7113(7)
0.6222(7)
0.5137(7)
0.2925(6)
0.1974(6)
0.1590(8)
0.2145(10)
0.3109(9)
0.3489(8)
0.0911(6)
-0.0101(7)
-0.1039(7)
-0.0998(9)
-0.0003(11)
0.0963(8)
0.2271(7)
0.1655(8)
0.1806(12)
0.2569(13)
0.3199(13)
0.3032(9)
0.5543(2)
0.5329(7)
0.5710(9)
0.5861(10)
0.5235(8)
0.6801(5)
0.4290(6)
0.1588(24)
0.1413(41)
0.1383(39)
0.5910(5)
0.5658(4)
0.5487(4)
0.5457(4)
0.5617(4)
0.6234(3)
0.4552(5)
0.4625(4)
0.4233(4)
0.4127(3)
0.2828(4)
0.4031(4)
0.3692(5)
0.3961(6)
0.4573(5)
0.4913(5)
0.4636(5)
0.3621(4)
0.4003(5)
0.3841(7)
0.3347(8)
0.2960(6)
0.3115(5)
0.2532(4)
0.2437(5)
0.2140(6)
0.1941(6)
0.2035(6)
0.2317(5)
0.2471(5)
0.2670(6)
0.2291(8)
0.1724(11)
0.1495(9)
0.1880(7)
0.4428(5)
0.4545(5)
0.3825(4)
0.3259(4)
0.3641(4)
0.4892(3)
0.5100(4)
0.5671(3)
0.3511(4)
0.3209(3)
0.3544(4)
0.3019(4)
0.3455(4)
0.3399(5)
0.2925(5)
0.2495(5)
0.2534(5)
0.2093(4)
0.1761(4)
0.1015(5)
0.0574(6)
0.0892(5)
0.1649(5)
0.3539(5)
0.3902(5)
0.3498(7)
0.2748(8)
0.2369(6)
0.2766(5)
0.5008(4)
0.5634(5)
0.6333(7)
0.6391(9)
0.5794(10)
0.5086(7)
F igu r e 1. Structural view of Mo(η3-C5H5O)(CO)2(CH3CN)-
Br (1a ). Selected bond lengths (Å): Mo-Br 2.624 (1), Mo-
C(1) 2.170 (5), Mo-C(2) 2.328 (4), Mo-C(4) 1.962 (3),
Mo-N 2.229 (3), C(1)-C(2) 1.392 (6), C(2)-C(3) 1.487 (7),
C(3)-C(3′) 1.503 (6), C(3)-O(1) 1.213 (8), C(4)-O(2) 1.149
(4).
C(9)
C(10)
C(11)
C(12)
C(13)
C(14)
C(15)
C(16)
C(17)
C(18)
C(19)
C(20)
C(21)
C(22)
C(23)
C(24)
C(25)
C(26)
C(27)
C(28)
C(29)
C(30)
C(31)
C(32)
P(3)
F igu r e 2. Structural view of Mo(η3-C5H5O)(CO)2(HBpz3)
(3a ).
0.10072(15) 0.33548(14)
F(1)
F(2)
F(3)
F(4)
0.0195(5)
0.1782(5)
0.1186(8)
0.0792(9)
0.0847(5)
0.1167(6)
0.0548(12)
0.0390(18)
0.0025(20)
0.3057(6)
0.3707(7)
0.2553(5)
0.4169(5)
0.3606(5)
0.3108(6)
0.3802(13)
0.4424(17)
0.5181(19)
equivalent proton resonances for the dienone ligand. For
complex 13, the protons of the cyclopentadienone ligand
are magnetically inequivalent, giving rise to four mul-
tiplets centered at 5.94 (1H), 5.89 (1H), 4.60 (1H), and
4.53 (1H) ppm, respectively. This is in agreement with
the observed asymmetric ligand arrangement as deter-
mined by X-ray crystallography (see below). The reso-
nances of the coligands HBpz3, bipy, and dppm are in
the expected ranges. The 13C{1H} NMR spectra of 9-13
contain no surprising features and it is sufficient to
point out that the resonances of the ketonic “carbonyl”
carbons are observed at 176.0, 174.5, 174.9, 172.5, and
173.8 ppm, respectively (for comparison, in [Mo(η5-
C5H5)(η4-C5H4O)(CO)2]+ the resonance of the ketonic
“carbonyl” carbon is found at 175.1 ppm3).
F(5)
F(6)
Nb
C(33)b
C(34)b
a
b
See footnote in Table 2. Acetonitrile solvent molecule with
refined site occupancy of 0.80(2).
complexes exhibit νCO frequencies only about 5-20 cm-1
higher than those of the corresponding tungsten com-
plexes, more pronounced effects are observed on replac-
ing HBpz3 by C5H5. The carbonyl stretching frequencies
of 9a are 33 and 69 cm-1 higher than the respective
carbonyl absorptions of [Mo(η5-C5H5)(η4-C5H4O)(CO)2]+,
implying that the metal center in 9a has become
somewhat less electron-rich.
Cr yst a l St r u ct u r es of Mo(η3-C5H 5O)(CO)2-
(CH3CN)2Br (1a ), Mo(η3-C5H5O)(CO)2(HBp z3) (3a ),
W(η3-C5H5O)(CO)2(HBp z3) (4), a n d W(η3-C5H5O)-
(CO)2(d p p m )Br (8). Structural views of complexes 1a ,
3a , and 8 are shown in Figures 1, 2, and 3, respectively.
Compound 4 is isostructural with 3a and is not depicted
because of its pronounced similarity with the latter both
with respect to bond distances and thermal vibrational
ellipsoids (on average the W-C/N bond distances are
shorter than the corresponding Mo-C/N bond distances
by only 0.007 Å). Selected bond lengths of complexes
3a , 4, and 8 are given in Table 8. These molecules can
In the 1H NMR spectra of complexes 9-12, the
cyclopentadienone ligand displays an AA′XX′ splitting
pattern of two apparent multiplets at about 6.5 (2H) and
4.5 ppm (2H) assignable to the â- and R-protons,
respectively. This assignment was afforded by compar-
ing the 1H NMR spectrum of 9a with that of the
2-methylcyclopentadienone complex 9b (see Experimen-
tal Section). Since complexes 9a -12 display mirror
symmetry (not in case of the 2-methylcyclopentadienone
complex 9b), one would, therefore, expect to observe

Mo and W Cyclopentadienone Complexes
Organometallics, Vol. 15, No. 1, 1996 187
Ta ble 8. Selected Bon d Len gth s (Å) for th e Meta l
Com p lexes in 3a , 4, 8, 10, a n d 13‚CH3CN (M )
Mo,W)
3a
4
8
10
13‚CH3CN
M-C1
M-C2
M-C3
M-C4
M-C5
M-C6
M-C7
M-N2
M-N4
M-N6
M-P1
M-P2
M-Br
C1-C2
C1-C5
C2-C3
C3-C4
C4-C5
C1-O1
2.179(4) 2.173(6) 2.194(5)
2.342(4) 2.330(7) 2.348(5) 2.335(5) 2.352(7)
2.246(5) 2.248(7)
2.252(5) 2.257(7)
2.351(4) 2.333(6) 2.337(5) 2.346(5) 2.372(7)
1.956(3) 1.961(6) 2.013(6) 2.032(5) 2.052(8)
1.957(3) 1.950(6) 1.951(5) 2.057(6) 2.023(8)
2.274(2) 2.261(4)
2.257(2) 2.248(4)
2.184(2) 2.184(4)
2.188(4)
2.203(4)
2.186(4)
2.565(1)
2.553(1)
2.654(1)
2.538(2)
2.611(2)
2.612(1)
1.397(5) 1.407(9) 1.433(9) 1.457(8) 1.474(10)
1.388(6) 1.413(9) 1.433(8) 1.458(8) 1.471(10)
1.482(5) 1.487(9) 1.513(10) 1.401(8) 1.399(10)
1.493(6) 1.489(10) 1.502(12) 1.417(8) 1.430(10)
1.496(5) 1.492(9) 1.470(9) 1.422(8) 1.390(10)
1.230(7) 1.224(9)
F igu r e 3. Structural view of W(η3-C5H5O)(CO)2(dppm)Br
(8).
C3-O1Aa 1.176(7) 1.205(13) 1.185(10)
C3-O1Ba 1.147(6) 1.156(10) 1.11(3)
C6-O2
C7-O3
be described as pseudooctahedral with the assumption
that the η3-cyclopentenoyl moiety occupies one coordina-
tion site. An equatorial plane can be defined to include
for complex 1a the two carbonyls (C(4)-O(2)), and the
two nitrogen atoms (N(1)), for complexes 3a and 4 the
two carbonyls (C(6)-O(2), C(7)-O(3)) and two of the
nitrogen atoms (N(2), N(4) of the HBpz3 ligand and for
complex 8 the two carbonyls (C(6)-O(2) and C(7)-O(3)),
the halogen (Br), and one of the phosphorus atoms (P(1))
of the dppm ligand. The η3-cyclopentenoyl ligand and
the halogen (Br), the third coordinating nitrogen (N(6))
of HBpz3, and the second phosphorus atom of dppm
(P(2)), respectively, lie trans to one another in apical
positions above and below the equatorial plane. More-
over, in the solid state complexes 1a , 3a , 4, and 8 are
found to adopt exclusively the exo conformation (I) with
1.152(3) 1.149(6) 1.131(6) 1.128(6) 1.129(8)
1.144(4) 1.165(7) 1.136(6) 1.124(6) 1.140(8)
a
The cyclopentenoyl moieties are disordered with the oxygen
atoms alternatively bonded to C3 or C4. Site occupation factors
for O1A/O1B are 0.53(1)/0.47(1) for 3a , 0.49(1)/0.51(1) for 4, and
0.79(1)/0.21(1) for 8.
F igu r e 4. Structural view of [W(η4-C5H4O)(CO)2(HBpz3)]-
-
respect to the orientation of the allyl moiety. In fact,
the same conformation is found for all complexes featur-
ing the M(η3-allyl)(CO)2 moiety (M ) Mo, W) whose
structures have been determined and it thus appears
to be a general trend.4,13,14 A rationalization of the
rotational preference of the η3-allyl group based on
EHMO calculations has been given in the literature.14
The cyclopentenoyl moieties of 1a , 3a , 4, and 8 are
distinctly bent and can be subdivided by two planes, one
defined by C(1), C(2), and C(3) (allyl fragment) and the
other defined by C(2), C(3), C(4), and C(5). The angle
between this plane is 27.6 (4), 26.3 (3), 28.5 (5), and 26.8
(5)°, respectively. The cyclopentenoyl ligands of 1a , 3a ,
4, and 8 exhibit a disorder of the ketonic oxygen atom.
For 1a , 3a , and 4, equal site occupancies are observed
with the oxygen atom being attached to either one of
the C(3) atoms (1a ) or C(3) and C(4) (3a , 4). For 8,
PF6 (10) (PF6 omitted for clarity).
presumably due to the asymmetry of this complex, a site
occupancy of 77% for the oxygen atom attached to C(3)
and 23% for the oxygen atom attached to C(4) is
observed. The M-CO and C-O distances are both
within the range of values reported for other molybde-
num and tungsten carbonyl complexes. There are no
structural features in complexes 1a , 3a , 4, and 8 that
indicate unusual deviations or distortions.
Cr ystal Str u ctu r es of [W(η4-C5H4O)(CO)2(HBpz3)]-
P F 6 (10) a n d [W(η4-C5H5O)(CO)2(d p p m )Br ]P F 6 (13).
Structural views of complexes 10 and 13 are shown in
Figures 4 and 5. While in 10 the dienone moiety is endo
oriented with respect to the CO ligands, complex 13
adopts the exo conformation. Noteworthily, the cyclo-
pentadienone ligand of the structurally related complex
[Mo(η5-C5H5)(η4-C5H4O)(CO)2]+ also adopts the endo
orientation.3 A main feature comprises the envelope
conformation of the cyclopentadienone ring which can
be subdivided into two planes, one defined by C(2), C(3),
(13) Faller, J . W.; Haitko, D. A.; Adams, R. D.; Chodosh, D. F. J .
Am. Chem. Soc. 1979, 101, 865, and references therein.
(14) Curtis, M. D.; Eisenstein, O. Organometallics 1984, 3, 887, and
references therein.

188 Organometallics, Vol. 15, No. 1, 1996
Mauthner et al.
Ta ble 9. Com p a r ison of Bon d Dista n ces (Å) a n d Rin g Dih ed r a l An gles (d eg) in Som e η4-Cyclop en ta d ien on e
(C5H4O) Com p lexes
2
1
5
O
3
4
M
compound
M-C2,5
M-C3,4
CdC C2,4-C3,5
C-C C3-C4
CdO
dihedral anglea
ref
Fe(η4-C5H4O)(CO)3
2.108
2.324
2.362
2.340
2.263
2.264
2.266
2.072
2.288
2.252
2.249
2.165
2.160
2.161
1.416
1.400
1.394
1.411
1.419
1.391
1.395
1.463
1.427
1.430
1.417
1.457
1.431
1.416
1.137
1.212
1.230
1.224
1.216
1.221
1.210
19.9
18.0
17.7
16.4
20.4
18.0
23.1
11
3
[Mo(η4-C5H4O)(CO)2(η5-C5H5)]+
[W(η4-C5H4O)(CO)2(HBpz3)]+ (10)
[W(η4-C5H4O)(CO)2(dppm)Br]+ (13)
Ru(η4-C5H4O)(η5-C5H5)Br
this work
this work
15
16
17
[Ru(η4-C5H4O)(η5-C5H5)(MeCN)]+
[Ru(η4-C5H4O)(η5-C5H5)(AsMe3)]+
a
Angle formed between the planes defined by C2, C3, C4, C5, and C1, C2, C5, O.
distances in complex 10 do not exhibit this pattern but
increase slightly in the order C(2)-C(3), C(3)-C(4), and
C(4)-(C5) being 1.401 (8), 1.417 (8), and 1.422 (8) Å,
respectively. The standard deviations, however, are
comparatively high. The bond distances between W and
the butadiene fragment in complexes 10 and 13 for C(3)
and C(4) are shorter than for C(2) and C(5) by about
0.1 Å (see Table 8) a feature that is characteristic of
η4-cyclopentadienone complexes in general. The C(1)-
O(1) distances of 10 and 13 are 1.230 (7) and 1.224 (9)
Å, respectively. Selected bond lengths may be found in
Table 8. For comparison, structural data of related
cyclopentadienone complexes are given in Table 9.
Ack n ow led gm en t. Financial support by the “J ubi-
la¨umsfond der o¨sterreichischen Nationalbank” is grate-
fully acknowledged (Project 5305).
F igu r e 5. Structural view of [W(η4-C5H4O)(CO)2-
(dppm)Br]PF6‚CH3CN (13‚CH3CN) (PF6- and CH3CN omit-
ted for clarity).
Su p p or tin g In for m a tion Ava ila ble: Listings of hydrogen
atomic coordinates, anisotropic temperature factors, complete
bond lengths and angles, and least-squares planes for com-
plexes 1a , 3a , 4, 8, 10, and 13 (50 pages). Ordering informa-
tion is given on any current masthead page.
C(4), and C(5) (butadiene fragment), and the other
defined by C(1), C(2), O(1), and C(5). The angles
between these planes are 17.5 (3) and 16.3 (4)° for 10
and 13, respectively. The diene C-C bonds in complex
13 adopt a short-long-short pattern (C(2)-C(3) )
1.399 (10) Å, C(4)-C(5) ) 1.390 (10) Å vs C(3)-C(4) )
1.430 (10) Å) as is the case for most cyclopentadienone
complexes reported thus far.2,3,15-17 The diene C-C
OM950618V
(15) Smith, T. P.; Kwan, K. S.; Taube, H.; Bino, A.; Cohen, S. Inorg.
Chem. 1984, 23, 1943.
(16) Kirchner, K.; Taube, H.; Scott, B.; Wilett, R. D. Inorg. Chem.
1993, 32, 1430.
(17) Kirchner, K.; Schmid, R.; Mereiter, K. Acta Crystallogr. Sect.
C 1995, 51, 361.