Synthesis of monosubstituted cyclopentadienyl ruthenium complexes from the reactions of 6-substituted fulvenes with RuHCl(PPh3)3

Article abstract of DOI:10.1021/om900527v

Reactions between 6-substitued fulvenes and the hydride complex RuHCl(PPh₃)₃ are described. Treatment of RuHCl(PPh ₃)₃ with fulvenes without sp³-CH protons at the carbon a to the exocyclic carbon of f

Full text of DOI:10.1021/om900527v

Organometallics 2009, 28, 5529–5535 5529
DOI: 10.1021/om900527v
Synthesis of Monosubstituted Cyclopentadienyl Ruthenium Complexes
from the Reactions of 6-Substituted Fulvenes with RuHCl(PPh3)3
Sunny Kai San Tse, Tongxun Guo, Herman Ho-Yung Sung, Ian Duncan Williams,
Zhenyang Lin,* and Guochen Jia*
Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay,
Kowloon, Hong Kong
Received June 18, 2009
Reactions between 6-substitued fulvenes and the hydride complex RuHCl(PPh3)3 are described.
Treatment of RuHCl(PPh3)3 with fulvenes without sp3-CH protons at the carbon R to the exocyclic
carbon of fulvene produces cleanly monosubstituted cyclopentadienyl ruthenium complexes
(η5-C5H4R)RuCl(PPh3)2 via hydride transfer to the electrophilic exocyclic carbon of fulvenes. When
fulvenes containing sp3-CH protons at the carbon R to the exocyclic carbon were used, the reactions
produce the expected (η5-C5H4R)RuCl(PPh3)2 complexes along with minor amounts of vinylcyclo-
pentadienyl ruthenium complexes due to dehydrogenation.
Introduction
CpRuCl(PPh3)2 is much less effective in terms of both activity
and selectivity.4 These observations prompted us to prepare
various cyclopentadienyl complexes of the type (η5-
C5H4R)RuCl(PPh3)2 with different substituents on the Cp ring.
The most common routes to complexes of the type
CpSubRuCl(PR3)2 (CpSub = substituted cyclopentadienyl)
include the reactions of CpSubH with RuCl3/PR3,5 the reac-
tions of RuCl2(PPh3)3 with CpSubH6,7 or [CpSub]-, which are
Cyclopentadienyl ruthenium complexes of the type (η5-
cyclopentadienyl)RuCl(PR3)2 are useful precursors for or-
ganometallic synthesis and catalysis.1-3 It has been demon-
strated that replacement of one or more of the hydrogens of
the cyclopentadienyl (C5H5) ring by other substituents can
lead to significant changes in the reactivity and catalytic
properties due to steric and electronic effects introduced
by these substituents. For example, in our study of ruthe-
nium-catalyzed reactions, we found that Cp*RuCl-
(PPh3)2 can efficiently mediate the coupling reactions of
azides with terminal alkynes to give selectively 1,5-disubsti-
tuted 1,2,3-triazoles, whereas the analogous complex
(3) Recent examples of catalytic reactions: (a) Tenaglia, A.; Marc, S.
J. Org. Chem. 2008, 73, 1397. (b) Yang, C. W.; Liu R. S. Tetrahedron Lett.
2007, 48, 5887. (c) Tenaglia, A.; Marc, S. J. Org. Chem. 2006, 71, 3569. (d)
Movassaghi, M.; Hill, M. D. J. Am. Chem. Soc. 2006, 128, 4592. (e) Del
Zotto, A.; Baratta, W.; Sandri, M.; Verardo, G.; Rigo, P. Eur. J. Inorg. Chem.
2004, 524. (f) Murakami, M.; Hori, S. J. Am. Chem. Soc. 2003, 125, 4720–
4721. (g) Kirss, R. U.; Ernst, R. D.; Arif, A. M. J. Organomet. Chem. 2004,
689, 419. (h) Pedro, F. M.; Santos, A. M.; Baratta, W.; K€uhn, F. E.
Organometallics 2007, 26, 302–309. (i) Tenaglia, A.; Marc, S. J. Org.
Chem. 2008, 73, 1397. (j) Baratta, W.; Herrmann, W. A.; Kratzer, R. M.;
Rigo, P. Organometallics 2000, 19, 3664. (k) Trost, B. M.; Livingston, R. C.
J. Am. Chem. Soc. 2008, 130, 11970. (l) Tenaglia, A.; Marc, S. J. Org.
Chem. 2006, 71, 3569. (m) Miura, Y.; Shibata, T.; Satoh, K.; Kamigaito, M.;
Okamoto, Y. J. Am. Chem. Soc. 2006, 128, 16 026.
*Corresponding author. E-mail: chjiag@ust.hk.
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(7) A similar reaction between C5H6 and RuHCl(CO)(PiPr3)2 oc-
ꢀ
curred to give CpRuH(CO)(PiPr3). Esteruelas, M. A.; Gomez, A. V.;
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r
2009 American Chemical Society
Published on Web 08/06/2009
pubs.acs.org/Organometallics

5530 Organometallics, Vol. 28, No. 18, 2009
Tse et al.
generated from the reactions of CpSubH with bases such as BuLi,
NaH, or tBuOK,8 the reactions of RuCl2(PPh3)3 with substi-
tuted cyclopentadienes having a TMS group on the ring,9 and
the reactions of PPh3 with [CpSubRuCl2]2, which were usually in
turn made from the reactions of CpSubH with RuCl3.10
Scheme 1
All the preparations require the availability of CpSubH.
While the preparations are efficient in many cases, difficulty
may be encountered in other cases, due to the unavailability
or the low stability of CpSubH starting materials. Conse-
quently, other routes to CpSubRuCl(PPh3)2 have been sought
after. Examples of these include the reactions of RuCl2-
(PPh3)3 with [CpSub -
] anions, which are generated in situ
from the reactions between spiro[2.4]hepta-4,6-diene and
nucleophiles,11 and the reactions of RuCl2(PPh3)3 with
lithium fulvenolates C5H4(COLiR).12
For example, complexes M(CH2Ph)4 (M=Zr, Hf) react with
6,60-dimethylfulvenes to give the insertion products
(C5H4CMe2CH2Ph)M(CH2Ph)3;17 Bu2ZrCl2 reacts with
6-arylfulvenes to give bis(benzylcyclopentadienyl)zirconium
dichloride complexes presumably through the insertion re-
action of a hydride intermediate generated in situ from
β-hydrogen elimination.18
In light of the success in the preparation of cyclopentadie-
nyl complexes of early transition metals via insertion reac-
tions of fulvene derivatives, one might expect that ruthenium
cyclopentadienyl complexes may also be easily prepared
from the reactions of fulvenes with ruthenium hydride com-
plexes. However, such a possibility has not been previously
explored. In this work, we have investigated reactions be-
tween RuHCl(PPh3)3 and 10 fulvene derivatives, which
enable us to obtain a series of (η5-C5H4R)RuCl(PPh3)2.
Substituted fulvenes, which are easily accessible, have been
demonstrated to be useful starting materials for the prepara-
tion of cyclopentadienyl complexes.13 A number of cyclo-
pentadienyl complexes have been obtained from fulvenes by
first converting fulvenes to cyclopentadienyl anions via their
reactions with reducing agents such as sodium and calcium14
or with nucleophiles such as lithium or Grignard reagents,15
LiAlH4 or LiBHEt3,16 followed by the reactions of the
cyclopentadienyl anions with suitable precursors. It has also
been demonstrated that early transition metal cyclopenta-
dienyl complexes could be obtained from the insertion
reactions of fulvenes with metal alkyl or hydride complexes.
(8) Recent examples using BuLi as the base: (a) Vogelgesang, J.;
Frick, A.; Huttner, G.; Kircher, P. Eur. J. Inorg. Chem. 2001, 949. (b)
Trost, B. M.; Vidal, B.; Thommen, M. Chem.;Eur. J. 1999, 5, 1055. (c)
Shaw, A. P.; Guan, H.; Norton, J. R. J. Organomet. Chem. 2008, 693, 1382.
Recent examples using NaH as the base: (d) Sun, Y.; Chan, H. S.; Dixneuf, P.
H.; Xie, Z. Chem. Commun. 2004, 2588. Recent examples using tBuOK as
Results and Discussion
Synthesis of Fulvenes. The structures of fulvene derivatives
used in this work are shown in Scheme 1. They were prepared
from the reactions of freshly distilled cyclopentadiene with
the corresponding aldehydes or ketones in methanol in the
presence of 2 equiv of pyrrolidine or NaOMe as the base, as
shown in eq 1 in Scheme 1.19 Except 6-pyrenyl- and 6-
phenanthrylfulvenes, all the fulvenes are known compounds.
The identities of the fulvenes have been confirmed by NMR
spectroscopy.
~
the base: (e) Bolano, S.; Gonsalvi, L.; Zanobini, F.; Vizza, F.; Bertolasi, V.;
Romerosa, A.; Peruzzini, M. J. Mol. Catal. (A) 2004, 224, 61. Recent
examples using NaHBEt3 as the base: (f) Kaulen, C.; Pala, C.; Hu, C.; Ganter,
C. Organometallics 2001, 20, 1614. (g) Lam, Y. F.; Yin, C.; Yeung, C. H.;
Ng, S. M.; Jia, G.; Lau, C. P. Organometallics 2002, 21, 1898.
(9) Zeijden, A.; Jimenez, J.; Mattheis, C.; Wagner, C.; Merzweiler, K.
Eur. J. Inorg. Chem. 1999, 1919.
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€
H.; Kruger, C. Chem. Ber. 1988, 121, 1719. (b) Chinn, M. S.; Heinekey, D.
M. J. Am. Chem. Soc. 1990, 112, 5166. (c) Jia, G.; Lough, A. J.; Morris, R.
H. Organometallics 1992, 11, 161. (d) Dutta, B.; Scolaro, C.; Scopelliti, R.;
Dyson, P. J.; Severin, K. Organometallics 2008, 27, 1355. (e) Akbayeva, D.
N.; Gonsalvi, L.; Oberhauser, W.; Peruzzini, M.; Vizza, F.; Br€uggeller, P.;
Romerosa, A.; Sava, G.; Bergamo, A. Chem. Commun. 2003, 264. (f)
Reactions of RuHCl(PPh3)3 with Fulvenes without sp3-CH
Protons at the carbon r to the Exocyclic (C6) Carbon.
Treatment of RuHCl(PPh3)3 with fulvenes 1S-6S in a
1:1.5 molar ratio in dichloromethane at room temperature
readily produced the corresponding monosubstituted cyclo-
pentadienyl ruthenium complexes 1-6 (Scheme 2). As mon-
itored by in situ 31P{1H} NMR spectroscopy, the reactions
are essentially completed in 1 h, giving the cyclopentadienyl
complexes (η5-C5H4R)RuCl(PPh3)2 as the only products.
The formation of (η5-C5H4R)RuCl(PPh3)2 is visually
marked by a color change of the solution from reddish-
purple to deep orange. A slight excess of fulvene was used in
our experiments in order to ensure the complete consump-
tion of the hydride complex in a short reaction time. The air-
stable yellow complexes were obtained in moderate to high
yields after recrystallization from n-hexane and diethyl ether.
The new complexes have been characterized by NMR and
elemental analysis. Consistent with the structures, the
ꢀ
Palacios, M. D.; Puerta, M. C.; Valerga, P.; Lledos, A.; Veilly, E. Inorg.
Chem. 2007, 46, 6958. (g) Tilley, T. D.; Grubbs, R. H.; Bercaw, J.
Organometallics 1984, 3, 274. (h) Dutta, B.; Solari, E.; Gauthier, S.;
Scopelliti, R.; Severin, K. Organometallics 2007, 26, 4791.
(11) Gorman, J. S. T.; Lynch, V.; Pagenkopf, B. L.; Young, B.
Tetrahedron Lett. 2003, 44, 5435.
€
(12) Kunz, D.; Frohlich, R.; Erker, G. Organometallics 2001, 20, 572.
€
(13) (a) Erker, G.; Kehr, G.; Frohlich, R. Organometallics 2008, 27, 3.
(b) Strohfeldt, K.; Tacke, M. Chem. Soc. Rev. 2008, 37, 1174. (c) Coville, N.
J.; Plooy, K. E.; Pickl, W. Coord. Chem. Rev. 1992, 116, 1.
€
(14) Use of Na, see for example: (a) Fischer, M.; Bonzli, P.; Stofer, B.;
Neuenschwander, M. Helv. Chim. Acta 1999, 82, 1509. Use of Ca, see for
example: (b) Kane, K. M.; Shapiro, P. J.; Vij, A.; Cubbon, R.; Rheingold, A.
€
L. Organometallics 1997, 16, 4567. (c) Sinnema, P. J.; Hohn, B.; Hubbard, R.
L.; Shapiro, P. J.; Twamley, B.; Blumenfeld, A.; Vij, A. Organometallics
2002, 21, 182. (d) Eisch, J. J.; Shi, X.; Owuor, F. A. Organometallics 1998,
17, 5219.
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3355.
(16) Use of LiAlH4: (a) Plazuk, D.; Le Bideau, F.; Perez-Luna, A.;
Stephan, E.; Vessierres, A.; Zakrzewski, J.; Jaouen, G. Appl. Organomet.
Chem. 2006, 20, 168. (b) Hopf, H., Sankararaman, S., Dix, I., Jones, P. G.,
Alt, H. G.; Licht, A. Eur. J. Inorg. Chem. 2002, 123. Use of LiBHEt3: (c)
(17) Rogers, J. S.; Lachicotte, R. J.; Bazan, G. C. Organometallics
1999, 18, 3976.
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Claffey, J.; Hogan, M.; M€uller-Bunz, H.; Pampillon, C.; Tacke, M. J.
Organomet. Chem. 2008, 693, 526. (d) Strohfeldt, K.; M€uller-Bunz, H.;
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ꢀ

Article
Organometallics, Vol. 28, No. 18, 2009 5531
Figure 1. ORTEP drawing of 2. Except those on C6-C8,
hydrogen atoms are omitted for clarity. Thermal ellipsoids are
˚
shown at the 35% probability level. Selected bond lengths (A)
Figure 2. ORTEP drawing of 4. Thermal ellipsoids are shown
˚
at the 40% probability level. Selected bond lengths (A)
and angles (deg): average Ru1-C(Cp), 2.211; Ru1-Cl1,
2.4462(7); Ru1-P1, 2.3036(7); Ru1-P2, 2.3195(8); P1-Ru1-
P2, 100.38(3); Ru1-C1-C6, 126.27(19).
and angles (deg): average Ru1-C(Cp), 2.207; Ru1-Cl1,
2.4359(12); Ru1-P1, 2.2988(10); Ru1-P2, 2.3314(11); C6-
C7, 1.489(5); C7-C8, 1.311(6); P1-Ru1-P2, 100.36(4); Ru1-
C1-C6, 125.3(3); C6-C7-C8, 123.4(5); C7-C8-C9, 129.0(5).
Scheme 2
31P{1H} NMR spectra show a sharp singlet peak in the
region 38-40 ppm (depending on the pendant group). The
1H NMR spectra display two signals for protons of cyclo-
pentadienyl rings at ca. 4.3 and 3.6 ppm.
The structures of the complexes (η5-C5H4CH2CHdCHPh)-
RuCl(PPh3)2 (2) (Figure 1), (η5-C5H4CH2(pyrenyl))RuCl-
(PPh3)2 (4) (Figure 2), and (η5-C5H4CHPh2)RuCl(PPh3)2 (6)
(Figure 3) have been confirmed by X-ray crystallography. In
each case, the molecule adopts a piano stool structure with two
PPh3 and a Cl ligand as the legs. The Cl ligand settles under the
substituent of the cyclopentadienyl ring. The P-Ru-Cl angles
Figure 3. ORTEP drawing of 6. Thermal ellipsoids are shown
˚
at the 35% probability level. Selected bond lengths (A) and
angles (deg): average Ru1-C(Cp), 2.2219; Ru1-Cl1, 2.4420(4);
Ru1-P1, 2.2961(4); Ru1-P2, 2.3306(4); P1-Ru1-P2,
99.929(14); Ru1-C1-C6, 126.36(10).
(close to 90°) are similar to those (88.23°, 89.15°) in CpRuCl-
(PPh3)2.20 The P-Ru-P angles (close to 100°) are slightly
smaller than that of CpRuCl(PPh3)2 (104°), presumably due to
(20) Bruce, M. I.; Wong, F. S.; Skelton, B. W.; White, A. H. J. Chem.
Soc., Dalton Trans. 1981, 1398.

5532 Organometallics, Vol. 28, No. 18, 2009
Tse et al.
Scheme 3
Scheme 4
6-(cycloheptyl)fulvene, the major product exhibits a 31P{1H}
signal at 40.34 ppm in the 31P{1H} NMR spectrum and 1H
signals at 4.20 and 3.59 ppm assignable to protons of a
1
cyclopentadienyl ring in the H NMR spectrum. The simi-
the steric effects of the substituents. The carbon directly bound
to the Cp ring is nearly coplanar with the Cp ring, while the
remaining part of the substituent bends away from the metal
center. The average carbon-metal distances of the Cp0Ru
fragments as well as the Ru-Cl and Ru-P bond distances are
similar to those reported for CpRuCl(PPh3)2.
larity in the NMR data of the product and complexes 1-6
and 7A suggests that they have similar coordination spheres.
Therefore the major product was assigned to complex 9A
(Scheme 3). The minor product displays a 31P{1H} signal
with a chemical shift very similar to that of the major
1
product. The H NMR spectrum shows, in addition to the
As mentioned above, the exocyclic C6 carbons of fulvenes
are electrophilic and can be attacked by nucleophiles. In our
reactions, the cyclopentadienyl ligand is presumably gener-
ated via a hydride transfer from RuHCl(PPh3)3 to the C6
carbon of the fulvenes.
signals of protons of the cyclopentadienyl ring at 4.54 and
3.48 ppm, a vinyl proton signal at 6.33 ppm. Consistent with
the presence of the vinyl group, the 13C{1H} NMR spectrum
exhibits singlet vinyl signals at 132 (dCH) and 138 ppm
CpCdCH) for the minor product.
Reactions of RuHCl(PPh3)3 with Fulvenes with Protons at
the Carbon r to the C6 carbon. When fulvenes containing
sp3-CH protons at the carbon R to the C6 carbon (7S-10S)
were allowed to react with RuHCl(PPh3)3, the reactions
generally give two products: an expected (η5-C5H4R)RuCl-
(PPh3)2 complex as the major product and a formally
dehydrogenated product, η5-vinylcyclopentadienyl ruthe-
nium complex, as the minor product. The relative amount
of the two products is dependent on the structures of the
starting fulvenes (Scheme 3). The reaction of RuHCl(PPh3)3
with 6-(cyclohexyl)fulvene gives (η5-C5H4-cyclohexyl)RuCl-
(PPh3)2 (8A) and [(η5-C5H4-cyclohexenyl)RuCl(PPh3)2 (8B)
in a molar ratio of ca. 4.5:1. It can be demonstrated that the
ratio of the complexes 8A and 8B does not change appreci-
ably when the reaction was carried out under a hydrogen
atmosphere.
Similar results were observed when 6-(cyclopentyl)fulvene
(7S) and 6-(cycloheptyl)fulvene (9S) were allowed to react with
RuHCl(PPh3)3. For 6-(cyclopentyl)fulvene, the reaction pro-
duced the expected product 7A and the dehydrogentated
product 7B in a molar ratio of 6.6:1. For 6-(cycloheptyl)-
fulvene, the reaction produced 9A and 9B in a molar ratio of
1.3:1. When the noncylic fulvene 6-(isopropyl)fulvene (10) was
used, the reaction produced 10A and 10B in a molar ratio of
13.1:1.
Scheme4 showsplausible pathways forthe formationof the
expected (η5-C5H4R)RuCl complexes 7A-10A (represented
as A) and the vinylcyclopentadienyl complexes 7B-10B
(represented as B). The hydride complex RuHCl(PPh3)3
may initially react with a fulvene to give the fulvene complex
C. Complex A can be generated via intermediate D formed by
aninsertion reactionofC inwhichthe hydride is transferred to
the C6 carbon of the fulvene.
The vinylcyclopentadienyl product B is formally a dehy-
drogenated product of A. However, it can be demonstrated
that once 8A is formed, it can not be converted to 8B. Thus
complex A is not the precursor to complex B. Vinylcyclopen-
tadienyl complexes of early transition metals can be prepared
from deprotonation reactions of fulvenes. For example, Zr-
(NMe2)4 reacts with 6,60-(dimethyl)fulvene to give (η5-C5H4-
(CMedCH2))Zr(NMe2)3,16 and 6,60-(dimethyl)fulvene reacts
with LDA/Mo(CO)6 to give a vinylcyclopentadienyl com-
plex.21 However, the basicity of the ruthenium hydride of
RuHCl(PPh3)3 may not be strong enough to deprotonate
fulvene. We therefore propose that vinylcyclopentadienyl
complex B may be formed from 16e- ruthenium fulvene
hydride complex E, generated from dissociation of PPh3 from
C. Oxidative addition of an allylic C-H bond (at the carbon
R to the C6 of the fulvene) of E would give intermediate F. B
can then be formed by reductive elimination of H2 followed by
Although our attempts to separate the products by recrys-
tallization or column chromatography were unsuccessful,
the identities of the products can be deduced from their
spectroscopic data. For example, for the reaction of
(21) Macomber, D. W.; Hart, W. P.; Rausch, M. D.; Priester, R. D.;
Pittman, C. U. Jr. J. Am. Chem. Soc. 1982, 104, 884.

Article
Organometallics, Vol. 28, No. 18, 2009 5533
rearrangement. Relevant observations include the reaction of
1,4-pentadienes (C5H8) with RuHCl(PPh3)3 to give the pen-
tadienyl complex (η5-C5H7)RuCl(PPh3)222a and the reaction
of 1,3-cycloheptadiene (C7H10) with RuHCl(PPh3)3 to give
cyclopentadienyl complex (η5-C7H9)RuCl(PPh3)2.22b Consis-
tent withthe mechanism, it was observed thatthe formationof
vinyl-cyclopentadienyl product is inhibited when reaction of
RuHCl(PPh3)3 with cycloheptylfulvene (9S) was carried out
in the presence of a 10-fold excess of PPh3, which suppressed
the formation of intermediates E and F.
In summary, reactions of RuHCl(PPh3)3 with fulvenes
without sp3-CH protons at the carbon R to the exocyclic
carbon of the fulvene provide a simple and efficient method
for the synthesis of monosubstituted cyclopentadienyl ruthe-
nium complexes of the type (η5-C5H4R)RuCl(PPh3)2 via
hydride transfer to the electrophilic exocyclic carbon of
fulvenes. When fulvenes containing sp3-CH protons at the
carbon R to the exocyclic carbon are used, the reactions also
give the expected complexes as the major products along
with small amounts of vinylcyclopentadienyl complexes due
to elimination of H2.
130.21, 129.30, 128.89, 127.71, 126.70, 126.17, 125.78, 125.28,
125.14, 124.22, 123.86, 123.71, 122.80, 120.45. MS (TOF CIþ):
m/z 279.11 (M).
6-Phenanthrenylfulvene (5S). Phenanthrene-9-carboxalde-
hyde, 605 mg, 2.93 mmol; reaction time, 72 h; yield, 503 mg
(orange solid), 67.5%. 1H NMR (400 MHz, CDCl3): δ 8.76 (d,
J=8.4 Hz, 1H), 8.70 (d, J=8.4 Hz, 1H), 8.14 (d, J=8 Hz, 1H),
7.96-7.93 (m, 2H), 7.87 (s, 1H), 7.74-7.62 (m, 4H), 6.69-6.62
(m, 2H), 6.53 (d, J = 2 Hz, 1H), 6.52 (d, J=1.6 Hz, 1H). 13C{1H}
NMR (100.62 MHz, CDCl3): δ 148.03, 136.79, 135.31, 133.12,
132.83, 132.01, 131.97, 131.48, 131.22, 130.91, 129.92, 128.05,
127.61, 127.59, 127.50, 126.45, 126.01, 123.74, 123.22, 122.09.
MS (TOF CIþ): m/z 255.11 (M þ H).
General Procedure for the Synthesis of (η5-C5H4R)RuCl-
(PPh3)2 (1-10). A fulvene solution in CH2Cl2 (6 mL) was added
dropwisely to a solution of RuHCl(PPh3)3 in CH2Cl2 (4 mL).
The mixture was stirred at room temperature for 2 h. After the
completion of the reaction, the solvent was removed by eva-
poration under vacuum. The residue was washed with n-hexane
and Et2O and then dried to afford the corresponding cyclopen-
tadienyl complexes.
(η5-C5H4CHt2Bu)RuCl(PPh3)2 (1). 6-Butylfulvene (1S),
56 mg, 0.417 mmol; RuHCl(PPh3)3, 255 mg, 0.276 mmol; yield,
1
172 mg, 78.3%. H NMR (400 MHz, C6D6): δ 7.83 (br, 12H,
PPh3), 7.07 (br, 18H, PPh3), 4.30 (s, 2H, Cp), 3.63 (s, 2H, Cp),
2.52 (s, 2H, CH2), 1.05 (s, 9H, CH3). 13C{1H} NMR (75.5 MHz,
CD2Cl2): δ 138.87 (m), 133.90, 128.68, 127.42 (PPh3), 104.64,
82.13, 76.43 (C5H4), 41.60 (CpCH2), 30.86 (CMe3), 29.52
(CMe3). 31P{1H} NMR (162 MHz, C6D6): δ 39.9 (s). Anal.
Calcd for C46H45ClP2Ru: C, 69.38; H, 5.7. Found: C, 69.60; H,
5.61.
Experimental Section
All manipulations were carried out under a nitrogen atmo-
sphere using standard Schlenk techniques, unless otherwise
stated. Solvents were distilled under nitrogen from sodium
and benzophenone (n-hexane, diethyl ether), sodium (THF,
benzene), or calcium hydride (CH2Cl2). The starting materials
(η5-C5H4CH2CHdCHPh)RuCl(PPh3)2 (2). 2S, 99 mg, 0.549
mmol; RuHCl(PPh3)3, 308 mg, 0.333 mmol; yield, 206 mg,
RuHCl(PPh3)3 1S-2S, 4S-6S,19 3S,24 9S,25 and 10S26 were
23
prepared following the procedures described in the literature.
All other reagents were used as purchased from Aldrich Che-
mical Co. Microanalyses were performed by M-H-W Labora-
tories (Phoenix, AZ). 1H, 13C{1H}, and 31P{1H} NMR spectra
were collected on a Bruker-400 spectrometer (400 MHz) or a
1
73.4%. H NMR (300 MHz, C6D6): δ 7.82 (br, 14H, PPh3),
7.40 (d, J=7.3 Hz, 2H, Ph), 7.24 (d, J=7.3 Hz, 2H, Ph), 7.16 (m,
1H, Ph), 7.06 (br, 16H, PPh3), 6.73-6.56 (m, 2H, CHdCH),
4.30 (s, 2H, Cp), 3.69 (d, J=4.83 Hz, 2H, CpCH2), 3.61 (s, 2H,
Cp). 13C{1H} NMR (75.5 MHz, CD2Cl2): δ 138.92 (m), 134.05
(virtual t, J=5.13 Hz), 128.92, 127.62 (virtual t, J=4.45 Hz)
(PPh3), 137.83, 128.64, 127.23, 126.24 (dCHPh), 131.19, 129.16
(CHdCHPh), 107.47, 80.17 (t, J=4.45 Hz), 76.91 (C5H4), 30.62
(CpCH2). 31P{1H} NMR (121.47 MHz, C6D6): δ 41.09 (s). Anal.
Calcd for C49H41ClP2Ru: C, 71.29; H, 5.15. Found: C, 71.56; H,
5.10.
Bruker ARX-300 spectrometer (300 MHz). H and 13C NMR
1
shifts are relative to TMS, and 31P chemical shifts are relative to
85% H3PO4. MS spectra were recorded on a Finnigan TSQ7000
spectrometer.
General Procedure for the Preparation of Fulvenes. An alde-
hyde or ketone (14.69 mmol) and freshly distilled cyclopenta-
diene (3.00 mL, 36.76 mmol, 2.5 equiv) were mixed in MeOH (15
mL). Pyrrolidine (2.40 mL, 29.22 mmol, 2 equiv) was added
dropwisely to the mixture, and the mixture was stirred at room
temperature. The reaction was monitored by TLC on an hourly
basis. After the completion of the reaction, acetic acid (1.20 mL,
20.94 mmol) was added and the mixture was stirred for a further
30 min. The product was extracted with dichloromethane (20
mL ꢀ 2), washed with a brine solution (20 mL ꢀ 2), and dried
over MgSO4. The product was purified by column chromatog-
raphy using n-hexane as the eluent.
6-Pyrenylfulvene (4S). 1-Pyrenecarboxaldehyde, 402 mg,
1.74 mmol; reaction time, 64 h; yield, 170 mg (orange solid),
34.6%. 1H NMR (400 MHz, acetone-d6): δ 8.57 (d, J=9.2 Hz,
1H), 8.44 (s, 1H), 8.04 (s, 1H), 8.38 (s, 2H), 8.33 (m, 2H), 8.26
(dd, J=17.6, 9.2 Hz, 2H), 8.17 (t, J=7.6 Hz, 1H), 6.83 (m, 1H),
6.77 (m, 1H), 6.70 (m, 2H). 13C{1H} NMR (100.62 MHz,
acetone-d6): δ 146.6, 134.99, 134.85, 131.26, 130.72, 130.25,
(η5-C5H4CH2tolyl)RuCl(PPh3)2 (3). 3S, 84 mg, 0.499 mmol;
RuHCl(PPh3)3, 298 mg, 0.322 mmol; yield, 165 mg, 61.6%. 1H
NMR (400 MHz, acetone-d6): δ 7.60 (br, 12H, PPh3), 7.43 (t, J=
7.2 Hz, 6H, PPh3), 7.33 (m, 12H, PPh3), 7.25 (dd, J=8 Hz, 4H,
C6H4-Me), 4.08 (s, 2H, Cp), 3.70 (s, 2H, CH2), 3.55 (s, 2H, Cp),
2.41 (s, 3H, C6H4-Me). 13C{1H} NMR (75.5 MHz, CD2Cl2): δ
138.5 (m), 133.90 (virtual t, J=4.9 Hz), 128.77, 127.47(virtual t,
J = 4.5 Hz) (PPh3), 137.93, 135.66, 129.07 (Carom. of Toyl),
108.11, 80.21, 76.87 (C5H4), 32.75 (CpCH2), 20.77 (CH3 of
Toyl). 31P{1H} NMR (161.97 MHz, acetone-d6): δ 39.4 (s).
Anal. Calcd for C49H43ClP2Ru: C, 70.88; H, 5.22. Found: C,
71.06; H, 5.18.
(η5-C5H4CH2pyrenyl)RuCl(PPh3)2 (4). 4S, 141 mg, 0.500
mmol; RuHCl(PPh3)3, 308 mg, 0.333 mmol; yield, 207 mg,
1
66.1%. H NMR (400 MHz, CDCl3): δ 8.60 (d, 1H, pyrene),
8.25 (m, 5H, pyrene), 8.12 (s, 3H, pyrene), 7.56 (br, 12H, PPh3),
7.33 (m, 8H, PPh3), 7.26 (m, 10H, PPh3), 4.51 (s, 2H, Cp), 4.19 (s,
2H, CH2), 3.42 (s, 2H, Cp). 31P{1H} NMR (161.97 MHz,
CDCl3): δ 39.71 (s). Anal. Calcd for C58H45ClP2Ru: C, 74.07;
H, 4.82. Found: C, 74.20; H, 5.00.
(22) (a) Mann, B. E.; Manning, P. W.; Spencer, C. M. J. Organomet.
Chem. 1986, 312, C64. (b) Grassi, M.; Mann, B. E.; Manning, P.; Spencer, C.
M. J. Organomet. Chem. 1986, 307, C55.
(η5-C5H4CH2phenanthrenyl)RuCl(PPh3)2 (5). 5S, 100 mg,
0.393 mmol; RuHCl(PPh3)3, 254 mg, 0.275 mmol; yield, 175 mg,
(23) Hallman, P. S.; McGarvey, B. R.; Wilkinson, G. J. Chem. Soc.
(A) 1968, 3143.
(24) Imafuku, K.; Inoue, K. Bull. Chem. Soc. Jpn. 1982, 55, 3242.
(25) Erden, I.; Xu, F. P.; Sadoun, A.; Smith, W.; Sheff, G.; Ossun, M.
J. Org. Chem. 1995, 60, 813.
1
69.44%. H NMR (400 MHz, CDCl3): δ 8.71 (d, J = 6.8 Hz,
1H, phenanthrene), 8.64 (d, J=6.8 Hz, 1H, phenanthrene), 8.23
(d, J = 6.8 Hz, 1H, phenanthrene), 7.83 (d, J = 6.8 Hz, 1H,
phenanthrene), 7.70 (s, 1H, phenanthrene), 7.61 (m, 4H,
(26) Jeffery, J.; Probitts, E. J.; Mawby, R. J. J. Chem. Soc., Dalton
Trans. 1984, 2423.

5534 Organometallics, Vol. 28, No. 18, 2009
Table 1. Crystal Data and Structure Refinement for 2, 4, and 6
Tse et al.
2
4
6
formula
fw
C
842.30
0.71073
monoclinic
P2(1)/c
15.2938(17)
23.070(3)
11.2784(12)
90
97.272(2)
90
3947.3(7)
4
1.417
0.582
1736
50H43ClP2Ru
C58H45ClP2Ru 1.5CH2Cl2
3
C54H45ClP2Ru CH2Cl2
3
1067.79
0.71073
977.29
1.54178
˚
wavelength, A
cryst syst
space group
triclinic
P1
triclinic
P1
˚
a, A
11.7631(11)
14.3743(14)
15.1703(14)
92.0960(10)
107.4580(10)
95.1120(10)
2431.8(4)
2
1.458
0.649
1094
10.4800(3)
14.2855(4)
16.7794(3)
91.329(2)
98.864(2)
111.207(2)
2305.48(10)
2
1.408
5.288
1004
2.67-67.72
23 585
˚
b, A
˚
c, A
R, deg
β, deg
γ, deg
˚
V, A
Z
dcalcd, g cm-3
abs coeff, mm-1
F(000)
θ range, deg
no. of rflns
1.34-26.00
21 658
1.41-26.00
25 037
no. of indep rflns
no. of data/restraints/params
goodness of fit on F2
final R indices (I > 2σ(I))
7683 (R(int) = 0.1035)
7683/0/487
0.977
R1 = 0.0515, wR2 = 0.0672
0.603 and -0.553
9420 (R(int) = 0.0372)
9420/0/614
1.003
R1 = 0.0393, wR2 = 0.0892
0.840 and -0.707
8179 (R(int) = 0.0266)
8179/0/558
1.023
R1 = 0.0230, wR2 = 0.0614
0.408 and -0.496
-3
˚
largest diff peak and hole, e A
phenanthrene), 7.43 (br, 12H, PPh3), 7.22 (m, 7H, PPh3), 7.12 (br,
11H, PPh3), 4.14 (s, 2H, CH2), 4.09 (s, 2H, Cp), 3.35 (s, 2H, Cp).
31P{1H} NMR (161.97 MHz, CDCl3): δ 39.61 (s). Anal. Calcd for
region 2.77-1.28 ppm 31P{1H} NMR (161.98 MHz, C6D6):
40.04 (s, 8A), 40.11 ppm (s, 8B). Anal. Calcd for C47H45ClP2Ru:
C, 69.92; H, 5.49. Found: C, 69.78; H, 5.51.
C56H45ClP2Ru CH2Cl2: C, 68.37; H, 4.73. Found: C, 68.04; H,
3
4.90.
(η5-C5H4CHPh2)RuCl(PPh3)2 (6). 6S, 130 mg, 0.564 mmol;
RuHCl(PPh3)3 4.02 mg, 0.435 mmol; yield, 306 mg, 78.8%. 1H
NMR (400 MHz, C6D6): δ 7.85 (d, J=6.4 Hz, 4H, Ph), 7.73 (br,
12H, PPh3), 7.30 (m, 3H, Ph), 7.16 (t, J=6.4 Hz, 3H, Ph), 7.02
(m, 18H, PPh3), 6.35 (s, 1H, CHPh2), 4.17 (s, 2H, Cp), 3.57 (s,
2H, Cp). 31P{1H} NMR (161.9 7 MHz, C6D6): δ 41.48. Anal.
Calcd for C54H45ClP2Ru CH2Cl2: C, 67.59; H, 4.85. Found: C,
3
68.7; H, 4.74.
(η5-C5H4-CH2cycloheptyl)RuCl(PPh3)2 (9A) and (η5-C5H4-
CH2cycloheptenyl)RuCl(PPh3)2 (9B). 9S, 73 mg, 0.455 mmol;
RuHCl(PPh3)3, 271 mg, 0.293 mmol; yield, 150 mg, 62.4%;
molar ratio of 9A:9B=1.2:1 (based on the integrations of Cp
proton signals). Characteristic 1H signals of 9A (400 MHz,
C6D6): δ 4.20 (s, 2H, Cp), 3.59 (s, 2H, Cp), 3.18 (m, 1H, CpCH
of cycloheptyl). Characteristic 1H signals of 9B (400 MHz,
C6D6): δ 6.33 (t, J = 6.6 Hz, 1H, CdCH), 4.54 (s, 2H, Cp),
3.48 (s, 2H, Cp). The 1H NMR signals of PPh3 in 9A and 9B are
overlapped in the region 7.79-7.05 ppm, and other CH2 signals
are overlapped in the region 2.97-1.62 ppm. 13C{1H} NMR
(100.62 MHz, CD2Cl2): δ 140.09-138.93 (m), 134.69 (virtual t,
J=4.73 Hz), 129.33, 128.03 (virtual q, J=4.33 Hz) (PPh3 of 9A
and 9B), 138.73, 132.19 (vinyl group of 9B), 119.35, 78.168 (t, J=
5.03 Hz), 76.25 (C5H4 of 9A), 111.45, 77.26, 77.21, 77.17 (C5H4
of 9B), 37.16, 35.55, 29.23, 26.91 (cycloheptyl group of 9A),
33.09, 32.44, 29.98, 27.61, 27.33 (cycloheptenyl group of 9B).
31P{1H} NMR (121.5 MHz, C6D6): δ 40.34 (s, 9A), 40.61 (s, 9B).
Anal. Calcd for C48H47ClP2Ru: C, 70.19; H, 5.65. Found: C,
70.39; H, 5.86.
(η5-C5H4CH2cyclopentyl)RuCl(PPh3)2 (7A) and (η5-C5H4-
CH2cyclopentenyl)RuCl(PPh3)2 (7B). 7S, 43 mg, 0.325 mmol;
RuHCl(PPh3)3, 203 mg, 0.219 mmol; yield, 106 mg, 63.9%;
molar ratio of 7A to 7B=6.6:1 (based on the integrations of Cp
proton signals). Characteristic 1H signals of 7A (400 MHz,
CDCl3): δ 3.91 (s, 2H, Cp), 3.30 (s, 2H, Cp), 2.92 (m, 1H, CpCH
of cyclopentyl), Characteristic signals of 7B (400 MHz, CDCl3):
δ 5.88 (s, 1H, dCH), 4.24 (s, 2H, Cp), 3.29 (s, 2H, Cp). The 1H
NMR signals of PPh3 in 7A and 7B are overlapped in the region
7.38-7.10 ppm, and other CH2 signals are overlapped in the
region 2.64-1.43 ppm. 31P{1H} NMR (161.98 MHz, C6D6):
40.72 (s, 7A), 40.53 ppm (s, 7B). Anal. Calcd for C46H43ClP2Ru:
C, 69.56; H, 5.46. Found: C, 69.35; H, 5.44.
(η5-C5H4-CH2cyclohexyl)RuCl(PPh3)2 (8A) and (η5-C5H4-
CH2cyclohexenyl)RuCl(PPh3)2 (8B). 8S, 42.6 mg, 0.29 mmol;
RuHCl(PPh3)3, 216 mg, 0.234 mmol; yield, 122 mg, 64.49%;
molar ratio of 8A:8B=4.52:1 (based on the integrations of Cp
proton signals). Characteristic 1H signals for 8A (400 MHz,
C6D6): δ 4.28 (s, 2H, Cp), 3.63 (s, 2H,Cp), 3.02 (m, 1H, CpCH of
cyclohexyl). Characteristic 1H signals for 8B (400 MHz, C6D6):
6.21 (s, 1H, dCH) 4.55 (s, 2H, Cp), 3.52 (s, 2H, Cp). The H
NMR signals of PPh3 in 8A and 8B are overlapped in the region
7.37-7.10 ppm, and other CH2 signals are overlapped in the
(η5-C5H4CH2CHMe2)RuCl(PPh3)2 (10A) and [(η5-C5H4-
CH2CHMe2)RuCl(PPh3)2] (10B). 10S, 59 mg, 0.49 mmol;
RuHCl(PPh3)3, 299 mg, 0.32 mmol; yield, 167 mg, 66.2%; molar
ratio of 10A:10B=13.1:1 (based on the integration of Cp ring
1

Article
Organometallics, Vol. 28, No. 18, 2009 5535
proton signals). Characteristic 1H signals of 10A (C6D6): δ 4.24
(s, 2H, Cp), 3.58 (s, 2H, Cp), 2.66 (d, J=6.8 Hz, 2H, CpCH2),
1.85 (m, 1H, CH2CHMe2), 1.06 (d, J=6.4 Hz, 6H, CHCH3).
Characteristic 1H signals of 10B (C6D6): δ 6.42 (s, 1H,
CpCHdCMe2), 4.59 (s, 2H, Cp), 3.66 (s, 2H, Cp), 0.433 (s,
6H, CMe2). The 1H NMR signals of PPh3 in 10A and 10B are
overlapped in the region 7.83-7.07 ppm. 31P{1H} NMR (161.98
MHz, C6D6): δ 40.28 (s, 10A), 40.38 (s, 10B). Anal. Calcd for
(4A) C45H43ClP2Ru: C, 69.09; H, 5.54. Found: C, 69.45; H, 5.63.
at 173 and 100 K respectively. Lattice determination and data
collection were carried out using SMART v.5.625 software. Data
reduction and absorption correction were performed using
SAINT v 6.26 and SADABS v 2.03, whereas the diffraction
intensity data of 6 were collected with an Oxford Diffraction
GeminiS Ultra with monochromatized Cu KR radiation (λ =
˚
1.54178 A) at 173 K. Lattice determination, data collection, and
reduction were carried out using CrysAlisPro 171.32.5. Absorp-
tion correction was performed using SADABS built in the
CrysAlisPro program suite. Structure solution and refinement
for all three compounds were performed using the SHELXTL
v.6.10 software package. They were solved by the direct methods
and refined by full-matrix least-squares on F2. All non-hydrogen
atoms were refined anisotropically. Hydrogen atoms were intro-
duced at their geometric positions and refined as riding atoms.
Acknowledgment. This work was supported by the
Hong Kong Research Grant Council (Project No.
HKUST 601306).
X-ray Crystallography Studies of 2, 4, and 6. The crystals were
mounted on a glass fiber, and the diffraction intensity data of 2
and 4 were collected with a Bruker Smart APEX CCD diffracto-
Supporting Information Available: X-ray crystallographic
files (CIF). This material is available free of charge via the
Internet at http://pubs.acs.org.
˚
meter with monochromatized Mo KR radiation (λ=0.71073 A)