Intramolecular diels-alder reactions in ruthenium vinylidene complexes containing anthracenyl groups

Article abstract of DOI:10.1021/om8011294

An intramolecular Diels-Alder (IMDA) reaction was observed at room temperature between an allyl group and a chloroanthracenyl group that were both bonded to the vinylidene ligand of the cationic ruthenium complex [Ru]=C=C(CH₂CH=CH₂)C

Full text of DOI:10.1021/om8011294

Organometallics 2009, 28, 1863–1871
1863
Intramolecular Diels-Alder Reactions in Ruthenium Vinylidene
Complexes Containing Anthracenyl Groups
Shu-Hao Chang, Wen-Ru Tsai, Hao-Wei Ma, Ying-Chih Lin,* Shou-Ling Huang,
Yi-Hung Liu, and Yu Wang
Department of Chemistry, National Taiwan UniVersity, Taipei, Taiwan 106, Republic of China
ReceiVed NoVember 26, 2008
An intramolecular Diels-Alder (IMDA) reaction was observed at room temperature between an allyl
group and a chloroanthracenyl group that were both bonded to the vinylidene ligand of the cationic
ruthenium complex [Ru]dCdC(CH2CHdCH2)CH(CH2CHdCH2)(C14H8Cl)+ (6; [Ru] ) Cp(PPh3)3Ru).
The vinylidene ligand functions as a mediator to bring the allyl and the chloroanthracenyl groups in
proximity for the reaction to take place. For the two allyl groups in 6, only the one at Cꢀ underwent the
reaction. In the analogous triethylphosphine complex 6′, more electron-donating triethylphosphine ligands
lower the rate of the IMDA reaction. For this IMDA reaction in several vinylidene complexes, each with
a nonchlorinated anthracenyl ligand, the rate of the reaction is accelerated by the presence of an unsaturated
functional group at Cγ of the vinylidene ligand, particularly by a terminal alkynyl substituent. The solid-
state structures of two IMDA reaction products have been determined by single-crystal X-ray diffraction
analysis.
roanthracenyl groups and vinyl groups bonded to the ligand.
The intramolecular Diels-Alder (IMDA) reaction5-7 takes place
under relatively mild conditions, yielding vinylidene complexes
with polycyclic ligands.
Introduction
As catalytic enyne chemistry has become the focus of many
recent explorations,1,2 an understanding of the chemical reactiv-
ity of vinylidene complexes containing additional olefinic
functionalities may disclose fundamental key steps in the
reactions of enynes.3 Considering that the vinylidene moiety
originates from a terminal alkynyl functionality,4 the entire
vinylidene ligand with an additional olefin group is perceived
as an enyne. We previously reported a novel metathesis of two
CdC double bonds in vinylidene complexes tethered with a
vinyl terminus.3 This metathesis process is observed in several
systems with 1,5-enyne. As the synthesis of vinylidene moieties
could be readily achieved by electrophilic addition of organic
halides to metal acetylide complexes, we aimed to study the
reaction of the vinylidene complex with an anthracenyl group
and a proximal vinyl group. Here we report the reactions of
several vinylidene complexes containing anthracenyl or chlo-
Results and Discussion
Intramolecular Diels-Alder Reaction in a Vinylidene
Complex with PPh3. A facile IMDA reaction was observed at
room temperature in the cationic ruthenium bis(triphenylphos-
phine) vinylidene complex [Ru]dCdC(CH2CHdCH2)CH-
(CH2CHdCH2)(C14H8Cl)+ (6; [Ru] ) Cp(PPh3)3Ru), with a 10-
chloroanthracenyl group and a terminal vinyl group each joining
to the vinylidene ligand at Cγ and Cꢀ, respectively (see Scheme
1). For 6 the two allyl groups were consecutively added to the
ligand by nucleophilic and electrophilic addition reactions. The
synthesis and characterization of these complexes shown in
Scheme 1 are described below.
Compound 2, a substituted propargyl alcohol, was first
synthesized from the reaction of 1 with HCt CMgBr according
to the literature method.8 The allenylidene complex 4 with a
10-chloroanthracenyl group bonded at Cγ as a deep blue powder
was then prepared in high yield from the reaction of 2 with
[Ru]Cl (3; [Ru] ) Cp(PPh3)2Ru)9 in the presence of KPF6 in
CH2Cl2.10 Analytical data of complex 4 support the proposed
* To whom correspondence should be addressed. E-mail: yclin@
ntu.edu.tw.
(1) (a) Driver, S. T.; Geissert, A. J. Chem. ReV. 2004, 104, 1317–1382.
(b) Nevado, C.; Ca´rdenas, D. J.; Echavarren, A. M. Chem. Eur. J. 2003, 9,
2627–2635. (c) Me´ndez, M.; Mamane, V.; Fu¨rstner, A. Chemtracts: Org.
Chem. 2003, 16, 397–425.
(2) (a) Mamane, V.; Gress, T.; Krause, H.; Fu¨rstner, A. J. Am. Chem.
Soc. 2004, 126, 8654–8655. (b) Harrak, Y.; Blaszykowski, C.; Bernard,
M.; Cariou, K.; Mainetti, E.; Mouries, V.; Dhimane, A. L.; Fensterbank,
L.; Malacria, M. J. Am. Chem. Soc. 2004, 126, 8656–8657. (c) Luzung,
M. R.; Markham, J. P.; Toste, F. D. J. Am. Chem. Soc. 2004, 126, 10858–
10859. (d) Nieto-Oberhuber, C.; Mun˜oz, M. P.; Bun˜uel, E.; Nevado, C.;
Ca´rdenas, D. J.; Echavarren, A. M. Angew. Chem., Int. Ed. 2004, 43, 2402–
2406.
(3) (a) Cheng, C. W.; Kuo, Y. C.; Chang, S. H.; Lin, Y. C.; Liu, Y. H.;
Wang, Y. J. Am. Chem. Soc. 2007, 129, 14974–14980. (b) Yen, Y. S.; Lin,
Y. C.; Huang, S. L.; Liu, Y. H.; Sung, H. L.; Wang, Y. J. Am. Chem. Soc.
2005, 127, 18037–18045.
(5) (a) Richter, F.; Bauer, M.; Perez, C.; Maichle-Mo¨ssmer, C.; Maier,
M. E. J. Org. Chem. 2002, 67, 2474–2480. (b) Tantillo, D. J.; Houk, K. N.;
Jung, M. E. J. Org. Chem. 2001, 66, 1938–1940.
(6) (a) Iafe, R. G.; Houk, K. N. J. Org. Chem. 2008, 73, 2679–2686.
(b) Larsen, S. D.; Grieco, P. A. J. Am. Chem. Soc. 1985, 107, 1768–1769.
(7) Ciganek, E. J. Org. Chem. 1980, 45, 1497–1505.
(8) Akiyama, S.; Nakagawa, M. Bull. Chem. Soc. Jpn. 1970, 43, 3561–
3566.
(4) (a) de los R´ıos, I.; Tenorio, M. J.; Puerta, M. C.; Valerga, P. J. Am.
Chem. Soc. 1997, 119, 6529–6538. (b) Tenorio, M. J.; Puerta, M. C.;
Valerga, P. Organometallics 1997, 16, 5528–5535. (c) Wakatsuki, Y.; Koga,
N.; Yamazaki, H.; Morokuma, K. J. Am. Chem. Soc. 1994, 116, 8105–
8111. (d) Touchard, D.; Haquette, P.; Pirio, N.; Toupet, L.; Dixneuf, P. H.
Organometallics 1993, 12, 3132–3139. (e) Silvestre, J.; Hoffmann, R. HelV.
Chim. Acta 1985, 68, 1461–1506.
(9) Bruce, M. I.; Hameister, C.; Swincer, A. G.; Wallis, R.; Ittel, S. D.
Inorg. Synth. 1990, 28, 270–272.
(10) (a) Werner, H. Chem. Commun. 1997, 903–904. (b) Touchard, D.;
Dixneuf, P. H. Coord. Chem. ReV. 1998, 178-180, 409–429. (c) Bruce,
M. I. Chem. ReV. 1998, 98, 2797–2858. (d) Bianchini, C.; Mantovani, N.;
Marchi, A.; Marvelli, L.; Masi, D.; Peruzzini, M.; Rossi, R.; Romerosa, A.
Organometallics 1999, 18, 4501–4508.
10.1021/om8011294 CCC: $40.75
2009 American Chemical Society
Publication on Web 02/25/2009

1864 Organometallics, Vol. 28, No. 6, 2009
Chang et al.
Scheme 1
formula. Also, spectroscopic data are characteristic for the
allenylidene ligand. For example, the H NMR spectrum of 4
exhibits one downfield singlet resonance at δ 10.52 assigned
chloroanthracenyl group. It could be reasonably guessed that
both vinyl groups are more or less in the vicinity of the
chloroanthracenyl group. However, only the group at Cꢀ
undergoes the IMDA reaction to yield 7. Analytical and
spectroscopic data of complex 7 support the proposed formula.
The mass spectrum of 7 exhibits the parent peak at m/z 1021.4.
The 31P NMR spectrum consists of two doublet resonances, in
accordance with the nonequivalent phosphorus nuclei. With two
stereogenic carbon centers in 7, this also indicates high
1
to the hydrogen at Cγ of the allenylidene ligand. The triplet
2
resonance at δ 300.9 with JPC ) 17.5 Hz in the 13C NMR
spectrum of 4 is assigned to CR.11 The 31P NMR spectrum shows
one singlet resonance at δ 46.34.
Treatment of 4 with CH2dCHCH2MgBr caused the allylation
to take place at Cγ, yielding the neutral acetylide complex 5,
which has been characterized by analytical and spectroscopic
methods. The 13C NMR spectrum of 5 showing a triplet
1
diastereoselectivity of the IMDA reaction. In the H NMR
spectrum of 7, only one allyl group pattern was found. In order
to gain further information to support the structure of 7, several
2-D NMR spectra, including COSY, HSQC, HMBC, and
NOESY, were obtained. In the COSY spectrum, the multiplet
resonance at δ 1.76 assigned to the methyne proton of the fused
six-membered ring shows correlations with that of the two
saturated internal methylene groups at δ 2.48, 2.17, 1.82, and
1.46. In the 13C spectrum, resonances of two bridgehead carbons
are upfield shifted to δ 58.3 and 71.3 and show no correlation
with any proton in the HSQC spectrum. In the HMBC spectrum,
the resonance at δ 58.3 shows correlations with that of two
protons on the two stereogenic methyne carbons. In the NOESY
spectrum, there is a NOE signal between the peaks at δ 1.76
and 4.28 assigned to the two methyne protons of the five-
membered ring, revealing the conformation of complex 7 such
that hydrogens on two stereogenic carbon atoms in this ring
are in a cis configuration. These NOE results reveal the RS/SR
conformation for 7.
2
resonance at δ 97.2 with JPC ) 25.3 Hz assigned to CR is
consistent with the presence of the acetylide ligand. The 31P
NMR spectrum displays two doublet resonances at δ 51.60 and
50.70 with 2JPP ) 37.2 Hz due to the presence of a stereogenic
carbon center on the acetylide ligand.
Then the electrophilic allylation reaction of 5, already with
an allyl group at Cγ of the acetylide ligand, with allyl iodide
takes place at Cꢀ in CH2Cl2 at room temperature, yielding the
cationic vinylidene complex 6, which is unstable at room
temperature. An IMDA reaction almost simultaneously occurs
between the terminal double bond of the newly added allylic
group and the chloroanthracenyl group at room temperature for
6, giving the cationic vinylidene complex 7 with a fused
polycyclic ring. After addition of allyl iodide to a solution of 5
at room temperature, complexes 6 and 7 concurrently appeared
in 4 h and the reaction finally afforded 7 as the single product
1
in 3 days. Interestingly, the H NMR spectrum of 6 obtained
from the mixture shows four doublet signals at δ 4.65, 4.31
and δ 4.43, 4.02 assignable to the protons of the two terminal
olefinic dCH2 groups. These signals are shifted noticeably
upfield, most likely due to the effect of the ring current of the
It is interesting to observe that, among two allyl groups, only
the group at Cꢀ of the vinylidene ligand is involved in the IMDA
reaction. The allyl group at Cγ is a spectator in the reaction. To
better understand if such an IMDA reaction is controlled by
the carbon chain length, we therefore carried out the alkylation
of 4 with CH2dCHCH2CH2MgBr, yielding the acetylide
complex 50 (see Scheme 1). Attempted allylation of 50 using
hydrous allyl iodide failed to give the desired product. However,
(11) (a) Wong, C. Y.; Che, C. M.; Chan, M. C. W.; Leung, K. H.;
Phillips, D. L.; Zhu, N. J. Am. Chem. Soc. 2004, 126, 2501–2514. (b)
Touchard, D.; Pirio, N.; Dixneuf, P. H. Organometallics 1995, 14, 4920–
4928.

Intramolecular Diels-Alder Reactions in Ru Complexes
Organometallics, Vol. 28, No. 6, 2009 1865
Scheme 2
from the reaction, the monosubstituted vinylidene complex 8
was obtained in high yield. No allyl group was added at Cꢀ on
the basis of the spectroscopic and analytical data. The acidic
medium used in the reaction possibly caused protonation to take
place to give 8. Treatment of 50 with HBF4 indeed afforded 8
in high yield. For 8 no IMDA reaction was observed, even at
elevated temperature. It is therefore assumed that only the allyl
group at Cꢀ could be utilized as a dienophile for the IMDA
reaction. Complex 8 with a butenyl group at Cγ has the same
number of C-C bonds between the terminal vinyl group and
the chloroanthrancenyl group as that in 6. Moreover, the
chemical shifts of two resonances of terminal olefinic hydrogens
at δ 5.04 and 4.99 are in a normal olefinic region. Accordingly,
the vinylidene ligand is considered as an essential mediator to
bring the chloroanthracenyl group and terminal vinyl group in
proximity and the metal fragment may provide an electronic
factor to initiate the reaction under mild conditions.
Vinylidene Complexes with PEt3 Ligands. To understand
the electronic effect of the metal fragment on this IMDA
reaction, we investigated similar reactions of the complex
[Ru′]Cl (3′; [Ru′] ) Cp(PEt3)2Ru),12 containing triethylphos-
phine ligands. The analogous end product 7′ resulting from the
IMDA reaction could be obtained, and an alternative synthetic
procedure, as shown in Scheme 2, was also utilized to obtain
the desired product.
with allyltrimethylsilane catalyzed by FeCl3 produced substituted
1,5-enynes in high yields. Following the established procedure,
treatment of 2 with allyltrimethylsilane in the presence of FeCl3
in CH3CN afforded the 1,5-enyne 10 (see Scheme 2). From the
1H NMR spectrum of 10 the normal coupling constant of 9.2
Hz between resonances at δ 5.35 and at δ 3.16 and 2.88,
assigned to the aliphatic methyne CH and methylene CH2,
respectively, indicates that the allylation takes place at the
propargylic site. In the formation of 10 it was proposed that
the dehydroxylation of 2 is first induced by FeCl3, yielding a
propargylic cation. This is followed by the addition of allylt-
rimethylsilane to give 10. Reaction of 3′ with 10 in the presence
of KPF6 in methanol directly afforded complex 8′ with an allyl
group bonded at Cγ of the vinylidene ligand. The reaction of 8′
with NaOMe then afforded the acetylide complex 5′.
Allylation of 5′ and a subsequent IMDA reaction are similar
to those in 5, except the latter reaction required mild thermolysis.
When 5′ was treated with allyl iodide, further allylation took
place at Cꢀ, yielding the cationic vinylidene complex 6′ with
two allyl groups at Cꢀ and Cγ of the vinylidene ligand. Complex
6′ in CH2Cl2 also underwent the IMDA reaction to yield 7′ under
mild heating. The 31P NMR spectrum of the mixture displays
2
two sets of two doublet resonances at δ 36.28, 35.16 with Jpp
) 33.9 Hz and at δ 38.13, 37.48 with 2Jpp ) 33.6 Hz, assigned
to 6′ and 7′, respectively. Additionally treatment of 5′ with
2-methylallyl iodide afforded the cationic vinylidene complex
6′′, which also underwent the IMDA reaction to yield 7′′. For
complete transformation of 6′′ to 7′′, a slightly higher temper-
ature, achieved by heating the CHCl3 solution to reflux, was
required. Possibly the electron-donating character and the steric
effect of the methyl group encumber the approach of this
dienophile to diene; therefore, a slightly higher temperature is
required for the IMDA reaction of 6′′. The triethylphosphine is
a better electron donor ligand than the triphenylphosphine,
making the vinylidene ligand of 6′ more electron rich. It is
known that a more electron-rich dienophile should hamper the
Diels-Alder reaction, since the strongest interaction takes
place between the HOMO of the diene and the LUMO of the
dienophile. It is therefore reasonable to assume that if the
The reaction of 3′ with 2 for 1 day initially gave a mixture
of the allenylidene complex 4′ and the γ-hydroxyvinylidene
complex 9′. The dehydration process normally occurring in the
hydroxyvinylidene complex is slower for 9′. After 3 days
complex 4′ was obtained as the sole product. The reaction of 4′
with CH2dCHCH2MgBr then yielded the acetylide complex 5′.
This procedure to yield 5′ could be achieved by a different
method using the enyne compound 10, which was prepared from
the reaction of 2 with allyltrimethylsilane catalyzed by FeCl3.13
It is known that the coupling reactions of propargylic alcohols
(12) Bruce, M. I.; Hameister, C.; Swincer, A. G.; Wallis, R. C. Inorg.
Synth. 1982, 21, 78–82.
(13) Zhan, Z. P.; Yu, J. L.; Liu, H. J.; Cui, Y. Y.; Yang, R. F.; Yang,
W. Z.; Li, J. P. J. Org. Chem. 2006, 71, 8298–8301.

1866 Organometallics, Vol. 28, No. 6, 2009
Chang et al.
Scheme 3
electronic effect is the factor controlling the rate of the IMDA
reaction, then the electron-donating triethylphosphine ligand
could preferentially make the vinyl group more electron rich.
Alternatively, the steric effect could also slow the rate of reaction
in the triethylphosphine system, in which the smaller steric bulk
of the phosphine ligand may not impede the allyl group to the
proximity of the diene.
solution than the other two complexes 6b and 6c, with 6c being
stable at room temperature. This result indicates that the IMDA
reaction could be affected by the neighboring group. A nearby
unsaturated group promotes the rate of the IMDA reaction.
Complexes 7a, 7b, and 7c are all stable in solution and have
been characterized by spectroscopic data which are similar to
those of 7. With a saturated ethyl group, the vinylidene complex
6c was isolated. The downfield triplet CR resonance at δ 358.3
Effects of Substituents at Cγ on the IMDA of the
Nonchlorinated Anthracenyl System. The synthetic procedures
and reaction products of the nonchlorinated anthracenyl system
as shown in Scheme 3 are similar to the chlorinated anthracenyl
system of PPh3 mentioned above. In this system, a number of
complexes 5a (R ) Ct CH), 5b (R ) CHdCH2), 5c (R )
CH2CH3), and 5e (R ) C2H4CHdCH2) were prepared to study
the effect of substituents at Cγ on the rate of reaction. Reaction
of 3 with 2a, which was obtained from 1a and HCt CMgBr,
afforded the cationic ruthenium allenylidene complex 4a as a
deep blue powder in high yield. When 4a was treated with
various Grignard reagents RMgBr, the C-C bond formation
took place at Cγ of the allenylidene ligand, yielding the
corresponding neutral acetylide complexes 5a, 5b, 5c, and 5e
(see Scheme 3). Interestingly, the reaction of 4a with the allyl
Grignard reagent CH2dCHCH2MgBr gave a mixture containing
5d (R ) CH2CHdCH2) and the product where allylation
reaction took place at the central ring of the anthracenyl group
in a ratio of 1:2. Attempts to separate these two products by
chromatography failed to give the desired product 5d. Thus,
the reaction of 5d was not further investigated. The reaction of
5a with allyl iodide in CH2Cl2 at room temperature directly
afforded the cationic complex 7a, possibly from the IMDA
reaction of the allylation intermediate. The intermediate 6a was
not detected. For the same reaction of 5b with allyl iodide,
complex 6b was observed by NMR and gradually transformed
into complex 7b at room temperature in 3 days. Similar reaction
of 5c with allyl iodide gave 6c, which could be isolated in pure
form and was transformed to complex 7c in refluxing CH2Cl2
in 5 days. The anticipated complex 6a with an unsaturated
alkynyl group is more reactive toward the IMDA reaction in
2
with JPC ) 14.7 Hz in the 13C NMR spectrum indicates the
presence of a vinylidene ligand. Two relatively upfield shifted
1
doublet H signals at δ 4.72 and 4.12, again due to the ring
current effect of the anthrancenyl group, with coupling constants
of 10.7 and 16.9 Hz, respectively, to the internal dCH are
assigned to the terminal allylic dCH2 group.
The attempted allylation reaction of 5e using hydrous allyl
iodide again yielded only the protonation product: i.e., the
monosubstituted vinylidene complex 8e in high yield. No allyl
group was added at Cꢀ if there was a proton source. This result
is similar to what was observed in the allylation reaction of 50
if hydrous iodide was used, yielding only the protonation product
8. For 8e no IMDA reaction was observed even at elevated
temperature. The IMDA reaction took place only for the
complex with an allyl group at Cꢀ. Spectroscopic data for
complex 8e clearly indicate the character of the vinylidene
ligand. A set of two doublet resonances at δ 44.06 and 39.27
2
with JPP ) 26.7 Hz appears in the 31P NMR spectrum of 8e.
However, if anhydrous allyl iodide was used, allylation occurred,
presumably yielding 6e. Mild thermolysis of 6e then generated
the Diels-Alder product 7e, characterized by spectroscopic data.
The only allyl group used for the Diels-Alder reaction is again
at Cꢀ.
Single crystals of the cationic complex 7c with an I3- anion
were obtained in CH2Cl2 at room temperature. Complex 7c was
characterized by an X-ray crystallographic study with the final
residual of refinement R1 (wR2) being 0.0439 (0.0799). An
ORTEP type view of the cationic complex 7c is shown in Figure
1, and selected bond distances and angles are given in the

Intramolecular Diels-Alder Reactions in Ru Complexes
Organometallics, Vol. 28, No. 6, 2009 1867
Figure 1. ORTEP drawing of 7c. Phenyl groups, except the C(ipso)
atoms on the phosphine ligands, have been omitted for clarity.
Selected bond lengths (Å) and angles (deg): Ru(1)-C(1), 1.869(4);
Ru(1)-P(1), 2.345(1); Ru(1)-P(2), 2.357(1); C(1)-C(2), 1.285(5);
C(2)-C(3), 1.537(5); C(2)-C(6), 1.551(6); C(3)-C(4), 1.545(6);
C(3)-C(16), 1.539(5); C(4)-C(5), 1.510(6); C(6)-C(7), 1.526(6);
C(7)-C(8), 1.530(6); C(7)-C(16), 1.573(5); C(8)-C(9), 1.546(6);
Ru(1)-C(1)-C(2), 172.5(3); C(1)-C(2)-C(3), 129.2(4); C(2)-
C(3)-C(4), 117.7(3); C(3)-C(4)-C(5), 112.6(4); P(1)-Ru(1)-P(2),
99.67(4); P(1)-Ru(1)-C(1), 91.00(1); P(2)-Ru(1)-C(1), 95.18(1).
Figure 2. ORTEP drawing of 7b. Phenyl groups, except the C(ipso)
atoms on the phosphine ligands, have been omitted for clarity.
Selected bond lengths (Å) and angles (deg): Ru(1)-C(1), 1.867(4);
Ru(1)-P(1), 2.343(1); Ru(1)-P(2), 2.364(1); C(1)-C(2), 1.289(5);
C(2)-C(3), 1.554(6); C(2)-C(20), 1.537(6); C(3)-C(4), 1.522(6);
C(4)-C(5), 1.547(6); C(4)-C(13), 1.579(6); C(5)-C(6), 1.554(6);
C(13)-C(20), 1.541(6); C(20)-C(21), 1.505(6); C(21)-C(22),
1.305(7); Ru(1)-C(1)-C(2), 172.3(3); C(1)-C(2)-C(3), 125.6(4);
C(2)-C(3)-C(4), 103.9(3); C(3)-C(4)-C(5), 118.0(4); P(1)-
Ru(1)-P(2), 99.66(4); P(1)-Ru(1)-C(1), 89.9 (1); P(2)-Ru(1)-
C(1), 95.2(1).
caption to the figure. The molecular structure shows a pseudo-
octahedral three-legged piano-stool coordination around the
ruthenium atom. Construction of the polycyclic structure result-
ing from the IMDA reaction is clearly seen by the formation of
the two new carbon-carbon bonds C(7)-C(16) and C(8)-C(9).
The two stereogenic carbon atoms C(3) and C(7) both adopt
an S configuration so that the SS form is obtained (the same
configuration as that in 7 with a chlorine atom). The hydrogen
atoms on the two stereogenic carbon atoms in the five-membered
ring are in a cis configuration, and this result is consistent with
the NOESY spectrum of complex 7. The bond length of
Ru(1)-C(1) in 7c is 1.869(4) Å, showing a typical RudC
double bond. The C(1)-C(2) bond distance of 1.285(5) Å is
well within the range of values reported for a CdC double bond
of a vinylidene ligand.14 The Ru(1)-C(1)-C(2) bond angle of
172.5(3)° shows almost linear geometry. The unique five-
membered ring of the polycyclic ligand adopts an envelope
form, with C(16) bending toward the Cp ring, causing the
bulkier phenyl groups of the anthracenyl ligand to remain in a
less crowded region. After the IMDA reaction, the center ring
of the anthracenyl part is in a boat conformation and the two
phenyl rings are far away from the two triphenylphosphine
ligands.
Single crystals of complex 7b were grown from a diethyl
ether/CH2Cl2 solution at -20 °C, and the crystal structure was
determined by an X-ray diffraction study. As shown in Figure
2, the molecular structure of complex 7b is similar to that of
7c. There is also an envelope form of the five-membered ring,
and C(13) is bent toward the Cp ring. The diastereoselectivity
is also similar to that in the formation of 7c. The two stereogenic
carbon atoms C(4) and C(20) adopt an R configuration so that
the RR form is obtained. There is no RS form observed in the
single crystals. Also, the C(21)-C(22) bond distance of the vinyl
group is 1.305(7) Å, showing a regular CdC double bond
character.
approach to a complex containing a polycyclic ligand under
remarkably mild conditions and gives good diastereoselectivity.
Only one diastereoisomer was obtained. The solid-state structure
provides a rational explanation for the diastereoselectivity of
this IMDA reaction. As shown in the lower left square of
Scheme 3, the steric effect of the substituent at Cγ may control
the stereochemistry of the C-C bond formation. No IMDA
reaction could be observed between the allyl group at Cγ and
the anthracenyl group.
In a report by Ciganek,7 a few 9,12-bridged ethano- and
ethenoanthracenes have been obtained by cyclization of 9-sub-
stituted anthracenes. These include amides, imines, amines,
ethers, thioethers, esters, acetals, and carbinols. These reactions
are almost all carried out at high temperature. Some reactions
also gave lower yields, due to difficulties in the isolation process.
In our case, we carry out the IMDA reaction mostly at room
temperature or with mild heating. The reaction is readily
monitored by NMR spectroscopy, and the IMDA products are
easily isolated. Several attempts by us to use CH3CN, CO and
mild oxidizing reagents to remove the organic portion from the
vinylidene complexes obtained from IMDA reactions failed to
give any isolable product.
Concluding Remarks. Intramolecular Diels-Alder reactions
were observed in vinylidene complexes with tethering chloro-
anthrancenyl/anthrancenyl and vinyl groups under mild condi-
tions. The vinylidene ligand mediates the reaction by bringing
the diene and dienenophile close together. The analogous
triethylphosphine complex displayed a slower rate of IMDA
reaction relative to that for the corresponding triphenylphosphine
complex. For vinylidene complexes with a nonchlorinated
anthrancenyl group, reactions of three complexes with different
substituents nearby revealed the promotional effect of a
neighboring unsaturated functional group.
This IMDA reaction between the allyl group at Cꢀ and the
anthracenyl group of the vinylidene ligand provides a direct
Experimental Section
(14) (a) Le Lagadec, R.; Roman, E.; Toupet, L.; Mu¨ller, U.; Dixneuf,
P. H. Organometallics 1994, 13, 5030–5039. (b) Sun, Y.; Chan, H. S.;
Dixneuf, P. H.; Xie, Z. Organometallics 2006, 25, 2719–2721.
General Procedures and Instruments. The manipulations were
performed under an atmosphere of dry nitrogen using vacuum-line

1868 Organometallics, Vol. 28, No. 6, 2009
Chang et al.
and standard Schlenk techniques. Solvents were dried by standard
methods and distilled under nitrogen before use. All reagents were
obtained from commercial suppliers and used without further
purification. The two ruthenium complexes Cp(PPh3)2RuCl (3) and
Cp(PEt3)2RuCl (3′) and compound 2a were prepared by following
the methods reported in the literature.8,9,12 The C, H analyses were
carried out with a Perkin-Elmer 2400 microanalyzer. Mass spectra
(FAB) were recorded using a JEOL SX-102A spectrometer;
3-nitrobenzyl alcohol (NBA) was used as the matrix. NMR spectra
were recorded on a Bruker AC-300 instrument at 300 MHz (1H),
121.5 MHz (31P), or 75.4 MHz (13C) using SiMe4 or 85% H3PO4
as standard or on an Avance 500 FT-NMR spectrometer.
Synthesis of 2. To a solution of 10-chloro-9-anthraldehyde (1;
1.02 g, 4.23 mmol) in 10 mL of THF was added HCt CMgBr (15
mL, 0.5 M in THF) at -78 °C, and the resulting solution was stirred
at room temperature for 12 h. The solvent was removed under
reduced pressure. An aliquot of water (100 mL) was added to the
mixture, and the product was extracted with diethyl ether (3 × 100
mL). The organic layer was washed with water (2 × 100 mL) and
dried with MgSO4. Solvent was removed under vacuum to give 2
(0.94 g, 85% yield). Anal. Calcd for C17H11ClO: C, 76.55; H, 4.16.
solution was stirred at room temperature for 12 h. The color of the
solution changed from orange to dark blue. After the solvent was
removed under vacuum, 30 mL of CH2Cl2 was added. The solution
was filtered through Celite, and the volume of the solution was
reduced to 5 mL under vacuum. Then 60 mL of hexane was added
to cause precipitation of a deep blue powder. After filtration, the
precipitate was washed with 10 mL of hexane twice and then dried
under vacuum to give the product 4′ (0.16 g, 86% yield). Anal.
Calcd for C34H44ClF6P3Ru: C, 51.29; H, 5.57. Found: C, 51.39; H,
1
3
5.66. H NMR (CDCl3): δ 10.55 (s, dCγH), 9.21 (d, 2H, JHH
)
8.9 Hz, anthracene), 8.72 (d, 2H, 3JHH ) 8.9 Hz, anthracene), 7.88
3
3
(t, 2H, JHH ) 7.8 Hz, anthracene), 7.65 (t, 2H, JHH ) 7.8 Hz,
anthracene), 5.50 (s, 5H, Cp), 2.06-1.69 (m, 12H, CH2), 1.17-0.99
(m, 18H, CH3). 31P NMR (CDCl3): δ 39.36 (s). MS: m/z 651.2
(M+).
Preparation of {[Ru]dCdCdCH(C14H9)}[PF6] (4a). Com-
pound 4a was prepared from complex 3 (0.50 g, 0.69 mmol), KPF6
(0.65 g, 3.53 mmol), and 2a (0.23 g, 0.99 mmol) using the same
procedure as that for 4. The product 4a (0.63 g) was isolated in
86% yield. Anal. Calcd for C58H45F6P3Ru: C, 66.35; H, 4.32. Found:
C, 66.71; H, 4.45. 1H NMR (CDCl3): δ 10.52 (s, dCγH), 9.17 (d,
2H, 3JHH ) 9.0 Hz, anthracene), 9.08 (s, 1H, anthracene), 8.17 (d,
1
3
Found: C, 76.39; H, 4.08. H NMR (CDCl3): δ 8.64 (d, 2H, JHH
3
3
3
2H, JHH ) 9.0 Hz, anthracene), 7.78 (t, 2H, JHH ) 8.2 Hz,
) 7.3 Hz, anthracene), 8.56 (d, 2H, JHH ) 7.3 Hz, anthracene),
3
7.60-7.52 (m, 4H, anthracene), 6.91 (d, 1H, 3JHH ) 2.3 Hz, CH),
anthracene), 7.54 (t, 2H, JHH ) 8.2 Hz, anthracene), 7.31-7.07
(m, 30H, Ph), 5.07 (s, 5H, Cp).13C{1H} NMR (CDCl3): δ 301.0 (t,
2JPC ) 17.5 Hz, CR), 216.6 (Cꢀ), 146.2 (Cγ), 135.1-124.3 (Ph,
anthracene), 93.2 (Cp). 31P NMR (CDCl3): δ 46.35 (s). MS: m/z
905.2 (M+).
2.87 (br s, 1H, OH), 2.66 (d, 1H, JHH ) 2.3 Hz, CH). 13C{1H}
3
NMR (CDCl3): δ 131.3-124.7 (anthracene), 83.7 (t C), 75.7
(t CH), 59.0 (CH). MS m/z: 265.9 (M+).
Synthesis of 10. To a solution of 2 (2.51 g, 9.41 mmol) in
CH3CN (10 mL) were added allyltrimethylsilane (3.42 g, 30 mmol)
and FeCl3 (0.16 g, 10 mol %) successively. The solution was stirred
at room temperature for 10 h. The solvent was removed under
vacuum, and the product was purified by silica gel column
chromatography with hexane as eluent. The solvent of the yellow
band was removed under vacuum to give 10 (1.67 g, 61% yield).
Anal. Calcd for C20H15Cl: C, 82.61; H, 5.20. Found: C, 82.73; H,
5.54. 1H NMR (CDCl3, 400 MHz): δ 8.71-8.67 (m, 4H, an-
thracene), 7.66-7.57 (m, 4H, anthracene), 6.01 (m, 1H, dCH),
5.35 (m, 1H, CH), 5.24 (d, 1H, 3JHH ) 17.0 Hz, trans dCH2), 5.14
Preparation of [Ru]Ct CCH(9-Cl-10-C14H8)CH2CHdCH2
(5). A solution of 4 (0.22 g, 0.20 mmol) in 10 mL of THF at -78
°C was treated with CH2dCHCH2MgBr (2 mL, 1.0 M in THF)
until the color turned to yellow. The mixture was stirred for 30
min while the temperature was slowly increased to 0 °C, and the
solvent was removed. The residue was extracted with 4 × 5 mL of
ether and filtered through Celite. The yellow solution was concen-
trated to give a light yellow powder. The precipitate was filtered
and washed with cold MeOH (10 mL) and dried under vacuum to
give 5 (0.15 g, 76% yield). Anal. Calcd for C61H49ClP2Ru: C, 74.72;
3
1
(d, 1H, JHH ) 10.9 Hz, cis dCH2), 3.25 (m, 1H, CH2), 2.88 (m,
H, 5.04. Found: C, 74.81; H, 5.11. H NMR (CDCl3): δ 8.61 (m,
4
1H, CH2), 2.48 (d, 1H, JHH, ) 2.7 Hz, t CH). 13C{1H} NMR
2H, anthracene), 7.50-6.66 (m, 36H, Ph), 5.99 (m, 1H, dCH),
5.39 (m, 1H, CH), 5.04-4.82 (m, 2H, dCH2), 4.22 (s, 5H, Cp),
3.15 (m, 1H, CH2), 2.60 (m, 1H, CH2). 13C{1H} NMR (CDCl3): δ
139.7-123.6 (Ph, anthracene, CCH2), 114.9 (dCH2), 112.1 (Cꢀ),
(CDCl3): δ 135.4 (dCH), 131.6-125.3 (anthracene), 116.1 (dCH2),
85.8 (t C), 72.01 (t CH), 40.4 (CH2), 31.4 (CH). MS: m/z 289.9
(M+).
97.2 (t, 2JPC ) 25.3 Hz, CR), 84.9 (Cp), 42.6 (CH2), 35.5 (CH). 31
P
Preparation of {[Ru]dCdCdCH(9-Cl-10-C14H8)}[PF6] (4).
To a Schlenk flask charged with complex 3 (0.55 g, 0.75 mmol)
and KPF6 (0.65 g, 3.53 mmol) was added methanol (20 mL) under
nitrogen. Then, 2 (0.27 g, 1.01 mmol) was added and the resulting
solution was stirred at room temperature for 5 h. The color of the
solution changed from orange to dark blue. After the solvent was
removed under vacuum, 30 mL of CH2Cl2 was added. The solution
was filtered through Celite, and the volume of the solution was
reduced to 7 mL under vacuum. Then 60 mL of hexane was added
to cause precipitation of a deep blue powder. After filtration, the
precipitate was washed with 10 mL of hexane twice and then dried
under vacuum to give the product 4 (0.71 g, 87% yield). Anal.
Calcd for C58H44ClF6P3Ru: C, 64.24; H, 4.09. Found: C, 64.37; H,
2
NMR (CDCl3): δ 51.62, 50.70 (2 d, JPP ) 37.2 Hz, PPh3). MS:
m/z 981.2 (M+).
Preparation of [Ru]Ct CCH(9-Cl-10-C14H8)CH2CH2CHd
CH2 (50). Complex 50 (0.13 g, 85% yield) was similarly prepared
from 4 (0.11 g, 0.10 mmol) and CH2dCHCH2CH2MgBr (2 mL,
0.5 M in THF). Anal. Calcd for C62H51ClP2Ru: C, 74.88; H, 5.17.
1
3
Found: C, 74.72; H, 5.20. H NMR (CDCl3): δ 9.86 (d, 1H, JHH
3
) 9.0 Hz, anthracene), 8.59 (d, 2H, JHH ) 8.9 Hz, anthracene),
3
8.37 (d, 1H, JHH ) 8.8 Hz, anthracene), 7.50-6.63 (m, 34H, Ph,
anthracene), 5.83 (m, 1H, dCH), 5.35 (m, 1H, CH), 4.90 (d, 1H,
3JHH ) 9.6 Hz, cis dCH2), 4.88 (d, 1H, JHH ) 16.8 Hz, trans
3
dCH2), 4.20 (s, 5H, Cp), 2.50 (m, 2H, CH2), 2.18 (m, 1H, CH2),
1.85 (m, 1H, CH2).13C{1H} NMR (CDCl3): δ 139.7-124.6 (s, Ph,
anthracene, dCH), 114.5 (Cꢀ), 112.1 (dCH2), 96.9 (t, 2JPC ) 25.0
Hz, CR), 84.8 (Cp), 37.2 (CH2), 34.5 (CH2), 32.8 (CH). 31P NMR
1
3
4.30. H NMR (CDCl3): δ 10.74 (s, dCγH), 9.10 (d, 2H, JHH
)
8.8 Hz, anthracene), 8.73 (d, 2H, 3JHH ) 8.8 Hz, anthracene), 7.75
3
3
(t, 2H, JHH ) 8.3 Hz, anthracene), 7.65 (t, 2H, JHH ) 8.3 Hz,
anthracene), 7.33-7.07 (m, 30H, Ph), 5.14 (s, 5H, Cp).13C{1H}
NMR (CDCl3): δ 305.3 (t, 2JPC ) 18.1 Hz, CR), 146.4 (Cꢀ), 137.9
(Cγ), 135.2-125.2 (Ph, anthracene), 93.7 (Cp). 31P NMR (CDCl3):
δ 46.13 (s). MS: m/z 939.2 (M+).
2
(CDCl3): δ 51.74, 50.72 (two d, Jpp ) 36.9 Hz, PPh3). MS: m/z
994.3 (M+).
Preparation of [Ru′]Ct CCH(9-Cl-10-C14H8)CH2CHdCH2
(5′). To a Schlenk flask charged with complex 8′ (0.20 g, 0.24 mmol
see below) was added a solution of NaOMe (0.13 g, 2.4 mmol) in
methanol (5 mL) under nitrogen. The solution was stirred at room
temperature for 5 min, and the color changed from orange to yellow.
The solvent was removed under vacuum. The product was extracted
Preparation of {[Ru′]dCdCdCH(9-Cl-10-C14H8)}[PF6] (4′).
To a Schlenk flask charged with complex 3′ (0.10 g, 0.23 mmol)
and KPF6 (0.13 g, 0.71 mmol) was added CH2Cl2 (10 mL) under
nitrogen. Then, 2 (0.14 g, 9.52 mmol) was added and the resulting

Intramolecular Diels-Alder Reactions in Ru Complexes
Organometallics, Vol. 28, No. 6, 2009 1869
with 4 × 5 mL of CH2Cl2 and filtered through Celite. The solvent
of the filtrate was removed under vacuum to give the product 5′
(0.12 g, 73% yield). Anal. Calcd for C37H49ClP2Ru: C, 64.20; H,
Hz, CR), 84.8 (Cp), 37.0 (CH2), 34.4 (CH2), 32.8 (CH). 31P NMR
2
(CDCl3): δ 51.90, 50.70 (two d, JPP ) 37.3 Hz, PPh3). MS: m/z
959.4 (M+).
1
7.13. Found: C, 64.31; H, 7.28. H NMR (CDCl3): δ 8.53 (d, 2H,
Preparation of {[Ru′]dCdC(CH2CHdCH2)CH(9-Cl-10-
C14H8)CH2CHdCH2}[I3] (6′). To a Schlenk flask charged with
complex 5′ (0.10 g, 0.14 mmol) in CH2Cl2 (5 mL) was added allyl
iodide (0.22 mL, 2.4 mmol) under nitrogen. The clear solution was
stirred for 4 h, and the color changed from yellow to deep red.
Then the solution was filtered and the volume of the filtrate was
reduced to 5 mL under vacuum. An aliquot of diethyl ether (50
mL) was added to cause precipitation of a pink powder. After
filtration, the precipitate was washed with 10 mL of diethyl ether
twice and dried under vacuum to give the product 6′ (0.21 g, 78%
yield). Anal. Calcd for C40H54ClI3P2Ru: C, 43.12; H, 4.89 (contains
3JHH ) 8.8 Hz, anthracene), 7.56-7.42 (m, 6H, anthracene), 5.91
(m, 1H, CdCH), 5.38 (t, 3JHH ) 7.7 Hz, 1H, CH), 4.97-4.82 (m,
2H, dCH2), 4.59 (s, 5H, Cp), 3.09-2.63 (m, 2H, dCCH2),
1.80-1.17 (m, 12H, CH2), 0.91-0.75 (m, 18H, CH3). 31P NMR
(CDCl3): δ 40.77, 40.46 (2 d, 2Jpp ) 39.4 Hz, PEt3). MS: m/z 692.6
(M+).
Preparation of [Ru]Ct CCH(9-Cl-10-C14H8)Ct CH (5a). A
solution of 4a (0.22 g, 0.21 mmol) in 10 mL of THF at -78 °C
was treated with HCt CMgBr (4 mL, 0.5 M in THF) until the color
turned to yellow. The mixture was stirred for 30 min while the
temperature was slowly increased to 0 °C, and the solvent was
removed. The product was extracted with 4 × 5 mL of ether and
filtered through Celite. The solvent was removed under vacuum to
give 5a (0.17 g, 90%). Anal. Calcd for C60H46P2Ru: C, 77.49; H,
1
a small amount of 7′). H NMR (CDCl3): δ 8.85-7.47 (m, 8H,
anthracene), 5.80 (m, 1H, dCH), 5.70 (m, 1H, CH), 5.21 (s, 5H,
Cp), 5.19 (m, 1H, dCH), 5.11-4.92 (m, 2H, dCH2), 4.67-4.53
(m, 2H, dCH2), 3.24-2.70 (m, 4H, CH2), 1.95-1.24 (m, 12H,
CH2), 1.13-0.74 (m, 18H, CH3). 31P NMR (CDCl3): δ 36.28, 35.16
1
4.99. Found: C, 77.45; H, 5.05. H NMR (CDCl3): δ 8.39 (s, 1H,
3
2
(2 d, JPP ) 33.9 Hz, PEt3). MS: m/z 733.3 (M+).
anthracene), 7.98 (d, 2H, JHH ) 8.4 Hz, anthracene), 7.44-6.62
(m, 36H, Ph, anthracene), 6.39 (br s, 1H, CH), 4.15 (s, 5H, Cp),
Preparation of Complex 6′′. Compound 6′′ (0.18 g, 92%) was
prepared similarly from the reaction of 5′ (0.14 g, 0.23 mmol) and
3-chloro-2-methyl-1-propene (0.3 mL, 2.74 mmol) at room tem-
perature in CH2Cl2. Anal. Calcd for C41H56ClI3P2Ru: C, 43.65; H,
5.00 (contains a small amount of 7′′). 1H NMR (CDCl3): δ
3
2.28 (d, 1H, JHH ) 2.6 Hz, Ct CH). 13C{1H} NMR (CDCl3): δ
139.1-124.7 (s, Ph, anthracene, dCH), 105.4 (Cꢀ), 99.2 (t, 2JPC
)
25.0 Hz, CR), 86.7 (t C), 84.9 (Cp), 81.4 (t CH), 30.2 (CH). 31P
2
NMR (CDCl3,): δ 51.30, 50.87 (2 d, JPP ) 36.5 Hz, PPh3). MS
ESI m/z: 931.2 (M+).
3
8.76-7.54 (m, 8H, anthracene), 5.85 (d, JHH ) 8.2 Hz, 1H, CH-
Preparation of [Ru]Ct CCH(C14H9)CHdCH2 (5b). A solution
of 4a (0.22 g, 0.21 mmol) in 10 mL of THF at -78 °C was treated
with CH2dCHMgBr (3 mL, 0.7 M in THF) until the color turned
to yellow. The mixture was stirred for 30 min while the temperature
was slowly increased to 0 °C, and the solvent was removed. The
residue was extracted with 4 × 5 mL of ether and filtered through
Celite. The yellow solution was concentrated to give a light yellow
powder. The precipitate was filtered and washed with cold MeOH
(10 mL) and dried under vacuum to give 5b (0.16 g, 80%). Anal.
Calcd for C60H48P2Ru: C, 77.32; H, 5.19. Found: C, 77.51; H, 5.24.
antracene), 5.05 (broad s, 1H, dCH2), 5.03 (broad s, 1H, dCH2),
3
5.00 (s, 5H, Cp), 5.20 (m, 1H, dCH), 4.66 (d, JHH ) 16.9 Hz,
1H, trans dCH2), 4.56 (d, 3JHH ) 9.9 Hz, 1H, cis dCH2), 3.27 (d,
2
2JHH ) 18.0 Hz, 1H, CH2), 2.81 (d, JHH ) 18.0 Hz, 1H, CH2),
2.99 (m, 1H, CH2), 2.75 (m, 1H, CH2), 1.71 (s, 3H, CH3), 1.87-1.64
(m, 6H, PCH2), 1.43-1.10 (m, 12H, PCH2), 1.07-0.99 (m, 9H,
CH3), 0.75-0.67 (m, 9H, CH3). 31C NMR (CDCl3): δ 348.0 (t,
2JCP ) 13.7 Hz, CR), 143.6-124.7 (anthracene), 135.1 (dCH), 134.7
(dC(Me)), 123.0 (Cꢀ), 116.9 (dCH2), 111.7 (dCH2), 89.2 (Cp),
53.4 (C-anthracene), 38.1 (CH2), 32.9 (CH2), 30.9 (CH3). 31P NMR
1H NMR (CDCl3): δ 8.39 (s, 1H, anthracene), 8.38 (d, 2H, 3JHH
)
2
(CDCl3): δ 36.36, 34.96 (two d, JPP ) 33.6 Hz, PEt3). MS: m/z
747.3 (M+).
8.4 Hz, anthracene), 7.49-6.61 (m, 36H, Ph, anthracene), 6.25 (m,
1H, dCH), 6.13 (br, 1H, CH), 6.03 (d, 1H, 3JHH ) 17.1 Hz, trans
dCH2), 5.29 (d, 1H, 3JHH ) 11.1 Hz, cis dCH2), 4.22 (s, 5H, Cp).
13C{1H} NMR (CDCl3): δ 142.6-124.4 (s, Ph, anthracene, dCH),
113.3 (Cꢀ), 109.3 (dCH2), 99.3 (t, 2JPC ) 25.3 Hz, CR), 84.9 (Cp),
Preparation of {[Ru]dCdC(CH2CHdCH2)CH(C14H9)CH2-
CH3}[I3] (6c). Complex 5c (0.09 g, 0.10 mmol) and CH2Cl2 (10
mL) were added in a Schlenk flask under nitrogen. To the resulting
solution was added allyl iodide (0.05 mL, 0.53 mmol), and this
mixture was stirred for 8 h at room temperature. The solvent was
removed in vacuo, and CH2Cl2 (2 × 5 mL) was used to extract the
product. The resulting solution was concentrated to ca. 5 mL and
added to stirred diethyl ether (60 mL) to produce a red precipitate,
which was filtered, washed with diethyl ether, and identified as 6c
(0.10 g, 92% yield). Anal. Calcd for C63H55I3P2Ru: C, 55.81; H,
2
38.3 (CH). 31P NMR (CDCl3): δ 51.63, 50.98 (two d, JPP ) 37.0
Hz, PPh3). MS: m/z 933.2 (M+).
Preparation of [Ru]Ct CCH(C14H9)CH2CH3 (5c). Complex
5c (0.18 g, 90% yield) was similarly prepared from 4a (0.22 g,
0.21 mmol) and CH3CH2MgBr (1 mL, 2 M in THF). Anal. Calcd
1
for C60H50P2Ru: C, 77.15; H, 5.40. Found: C, 77.32; H, 5.51. H
NMR (CDCl3): δ 9.92 (br, 1H, anthracene), 8.45 (m, 2H, an-
thracene), 8.06 (m, 2H, anthracene), 7.64-6.67 (m, 34H, Ph,
1
4.09. Found: C, 56.01; H, 4.15. H NMR (CDCl3): δ 9.19 (d, 1H,
3JHH ) 8.6 Hz, anthracene), 8.49 (s, 1H, anthracene), 8.15 (d, 1H,
3
anthracene), 5.32 (t, 1H, JHH ) 7.5 Hz, CH), 4.30 (s, 5H, Cp),
3J
3JHH ) 8.5 Hz, anthracene), 8.06 (d, 1H,
) 11.1 Hz,
HH
2.46 (m, 1H, CH2), 1.96 (m, 1H, CH2), 1.13 (t, 3H, 3JHH ) 7.3 Hz,
CH3).13C{1H} NMR (CDCl3): δ 139.9-124.4 (s, Ph, anthracene),
3
anthracene), 8.04 (d, 1H, JHH ) 9.8 Hz, anthracene), 7.83-6.80
3
(m, 34H, Ph, anthracene), 5.45 (br d, 1H, JHH ) 10.7 Hz, CH),
2
112.9 (Cꢀ), 95.4 (t, JPC ) 25.3 Hz, CR), 84.9 (Cp), 37.1 (CH2),
3
5.22 (m, 1H, dCH), 5.05 (s, 5H, Cp), 4.72 (d, 1H, JHH ) 10.7
31.3 (CH), 13.7 (CH3). 31P NMR (CDCl3): δ 52.02, 50.68 (two d,
2JPP ) 37.4 Hz, PPh3). MS: m/z 934.06 (M+).
3
Hz, cis dCH2), 4.12 (d, 1H, JHH ) 16.9 Hz, trans dCH2),
2.51-2.13 (m, 4H, CH2), 1.21 (t, 3H, 3JHH ) 7.1 Hz, CH3). 13C{1H}
2
Preparation of [Ru]Ct CCH(C14H9)CH2CH2CHdCH2 (5e).
Complex 5e (0.19 g, 82% yield) was similarly prepared from 4a
(0.22 g, 0.21 mmol) and CH2)CHCH2CH2MgBr (4 mL, 0.5 M in
THF). Anal. Calcd for C62H52P2Ru: C, 77.56; H, 5.46. Found: C,
NMR (CDCl3): δ 356.3 (t, JPC ) 14.7 Hz, CR), 145.73-120.4
(dCH, Ph, anthracene, Cꢀ), 118.4 (dCH2), 93.5 (Cp), 37.8 (CH2),
29.3(CH2), 28.51 (CH), 12.8 (CH3). 31P{1H} NMR (CDCl3): δ
41.17, 39.22 (2 d, JPP ) 27.6 Hz, PPh3). MS: m/z 975.3 (M+).
2
1
3
77.42; H, 5.52. H NMR (CDCl3): δ 8.38 (d, 2H, JHH ) 5.2 Hz,
anthracene), 8.01 (m, 3H, anthracene), 7.55-6.60 (m, 34H, Ph,
anthracene), 5.81 (m, 1H, dCH), 5.38 (m, 1H, CH), 4.89 (d, 1H,
Preparation of Complex 7. Complex 5 (0.20 g, 0.21 mmol)
was added into a Schlenk flask, and CH2Cl2 (10 mL) was then added
under nitrogen. To the resulting solution was added allyl iodide
(0.10 mL, 1.06 mmol), and the mixture was stirred for 3 days at
room temperature. The solvent was removed in vacuo, and CH2Cl2
(2 × 5 mL) was used to extract the product. The resulting solution
was concentrated to ca. 5 mL and added to stirred diethyl ether
3JHH ) 11.2 Hz, cis dCH2), 4.85 (d, 1H, JHH ) 14.6 Hz, trans
3
dCH2), 4.23 (s, 5H, Cp), 2.53 (m, 2H, CH2), 2.21 (m, 1H, CH2),
1.85 (m, 1H, CH2). 13C{1H} NMR (CDCl3): δ 139.8-123.3 (s, Ph,
anthracene, dCH), 114.3 (Cꢀ), 112.4 (dCH2), 95.7 (t, 2JPC ) 25.3

1870 Organometallics, Vol. 28, No. 6, 2009
Chang et al.
Table 1. Crystal Data and Refinement Parameters for Complexes
7b and 7c
(60 mL) to produce a yellow precipitate. The powder was filtered,
washed with diethyl ether, and dried under vacuum to give 7 (0.22
g, 93% yield). Anal. Calcd for C64H54ClI3P2Ru: C, 54.82; H, 3.88.
Found: C, 54.91; H, 3.95. 1H NMR (CDCl3): δ 7.85-7.04 (m, 38H,
Ph), 5.72 (m, 1H, dCH), 5.27 (s, 5H, Cp), 5.11 (m, 2H, dCH2),
4.28 (br s, 1H, CH), 3.42 (m, 1H, CH2), 3.19 (m, 1H, CH2), 2.48
(m, 1H, CH2), 2.17 (m, 1H, CH2), 1.82 (m, 1H, CH2), 1.76 (m,
7b
7c
formula
C63H53I3P2Ru
1353.76
P21/n
16.7766(3)
15.2633(2)
21.3190(4)
96.402(1)
5425.03(16); 4
27.5
2.095
12 385; 0.0499
622
0.0489
0.1211
C63H55I3P2Ru
1355.78
P21/n
16.8783(3)
15.2258(3)
21.2754(5)
96.934(2)
5427.50(2); 4
27.5
2.094
12 421; 0.0979
622
0.0439
0.0799
mass (amu)
space group
a (Å)
b (Å)
c (Å)
2
1H, CH), 1.46 (m, 1H, CH2). 13C NMR (CDCl3): δ 354.6 (t, JPC
) 15.6 Hz, CR), 144.08-121.1 (Ph) 137.7 (dCH), 129.8 (s, Cꢀ),
117.1 (dCH2), 93.7 (s, Cp), 71.3(s, CCl), 58.3 (s, C(bridgehead)),
47.3 (s, CH), 44.4 (s, CH), 43.8 (s, CH2), 36.4 (s, CH2), 31.9 (s,
ꢀ (deg)
V (Å3); Z
θmax (deg)
2
CH2). 31P NMR (CDCl3): δ 42.88, 40.34 (2 d, JPP ) 27.5 Hz).
abs coeff, µ(Mo KR) (mm-1
no. of indep rflns; Rint
no. of params
R1 for I > 2σ(I)
wR2, all data
goodness of fit on F2
)
MS: m/z 1021.4 (M+).
Preparation of Complex 7′. To a Schlenk flask charged with
complex 6′ (0.10 g, 0.090 mmol) was added CH2Cl2 (5 mL) under
nitrogen. The clear solution was stirred at 40 °C for 5 days. The
solution was filtered, and the volume of the filtrate was reduced to
2 mL under vacuum. Then 50 mL of diethyl ether was added to
cause precipitation of an orange powder. After filtration, the
precipitate was washed with 10 mL of diethyl ether twice and dried
under vacuum to give the product 7′ (0.08 g, 80% yield). Anal.
Calcd for C40H54ClI3P2Ru: C, 43.12; H, 4.89. Found: C, 43.26; H,
0.945
0.830
3
CH), 2.73 (d, 1H, JHH ) 3 Hz, t CH), 2,55 (m, 1H, CH2), 1.93
(m, 2H, CH2), 1.46 (m, 1H, CH), 1.15 (m, 1H, CH2). 13C{1H} NMR
2
(CDCl3): δ 353.8, 353.7 (2d, JPC ) 13.6 Hz, CR), 145.1-120.2
(Ph, anthracene, Cꢀ), 93.9 (s, Cp), 83.8 (s, t C), 75.7 (s, t CH),
57.4 (s, C(bridgehead)), 45.3 (s, CH(bridgehead)), 45.2 (s, CH),
32.8 (s, CH), 32.7 (s, CH2), 31.9 (s, CH2). 31P{1H} NMR (CDCl3):
1
4.97. H NMR (CDCl3): δ 7.78-7.16 (m, 8H, Ph), 6.04 (m, 1H,
2
δ 43.01; 41.64 (2 d, JPP ) 27.18 Hz). MS: m/z 971.2 (M+).
dCH), 5.55 (s, 5H, Cp), 5.32-5.28 (m, 2H, dCH2), 4.30 (broad
singlet, 1H, CH), 3.36-3.05 (m, 2H, CH2), 3.10-3.05 (m, 1H,
CH2), 2.33-2.24 (m, 2H, CH2), 2.00-1.72 (m, 12H, CH2), 1.94
(m, 1H, CH), 1.72 (m, 1H, CH), 1.22-1.03 (m, 18H, CH3). 13C
Preparation of Complex 7b. To a Schlenk flask containing 5b
(0.10 g, 0.11 mmol) was added CH2Cl2 (10 mL) under nitrogen.
To the resulting solution was added allyl iodide (0.05 mL, 0.53
mmol), and this mixture was stirred for 3 days at room temperature.
The solvent was removed in vacuo, and CH2Cl2 (2 × 5 mL) was
used to extract the product. The resulting solution was concentrated
to ca. 5 mL and added to stirred diethyl ether (60 mL) to produce
a red precipitate. The powder was filtered, washed with diethyl
ether, and identified as 7b (0.10 g, 83% yield). Anal. Calcd for
C63H53I3P2Ru: C, 55.89; H, 3.95. Found: C, 55.93; H, 4.01. 1H NMR
2
NMR (CDCl3): δ 346.9 (t, JPP ) 14.2 Hz, CR), 127.8 (Cꢀ),
144.3-120.9 (Ph), 137.1 (dCH), 116.8 (dCH2), 89.7 (Cp), 71.3
(C-Cl), 58.3 (C(bridge head)), 46.8 (CH), 42.9 (CH), 43.9 (CH2),
35.3 (CH2), 32.7 (CH2), 23.5-23.2 (PEt3), 8.8-8.7 (PEt3). 31P NMR
(CDCl3): δ 38.13, 37.48 (2 d, 2JPP ) 33.6 Hz, PEt3). MS: m/z 733.3
(M+).
Preparation of Complex 7′′. To a Schlenk flask charged with
complex 6′′ (0.21 g, 0.23 mmol) was added CHCl3 (10 mL) under
nitrogen. The clear solution was heated to reflux for 2 days. Then
the solution was filtered and the volume of the filtrate was reduced
to 2 mL under vacuum. An aliquot of petroleum ether (50 mL)
was added to cause precipitation of an orange powder. After
filtration, the precipitate was washed with 10 mL of petroleum ether
twice and dried under vacuum to give the product 7′′ (0.17 g, 82%
yield). Anal. Calcd for C41H56ClI3P2Ru: C, 43.65; H, 5.00. Found:
3
(CDCl3): δ 7.99 (d, 1H, JHH ) 7.2 Hz, anthracene), 7.43-6.83
3
(m, 37H, Ph, anthracene), 6.02 (m, 1H, dCH), 5.47 (d, 1H, JHH
) 10.4 Hz, cis dCH2), 5.42 (d, 1H, 3JHH ) 17.2 Hz, trans dCH2),
3
5.21 (s, 5H, Cp), 4.87 (br d, 1H, JHH ) 8.2 Hz, CH), 4.25 (br s,
1H, CH), 2,53 (m, 1H, CH2), 1.85 (m, 2H, CH2), 1.57 (m, 1H,
2
CH), 1.04 (m, 1H, CH2). 13C NMR (CDCl3): δ 353.4 (t, JPC
)
16.5 Hz, CR), 155.1-120.9 (Ph, anthracene, CHdCH2, Cꢀ), 93.6
(Cp), 56.9 (C(bridgehead)), 49.7 (CH), 46.5 (CH(bridgehead)), 45.6
(CH), 32.5 (CH2), 31.3 (CH2). 31P NMR (CDCl3): δ 43.29, 40.90
1
C, 43.79; H, 5.21. H NMR (CDCl3): δ 7.76-7.18 (m, 8H, Ph),
2
(2 d, JPP ) 27.7 Hz). MS: m/z 973.2 (M+).
3
6.05 (m, 1H, dCH), 5.49 (s, 5H, Cp), 5.28 (d, JHH ) 17.3 Hz,
Preparation of Complex 7c. A solution of complex 6c (0.10 g,
0.07 mmol) in CH2Cl2 (15 mL) was heated to 40 °C for 6 days.
Then the solution was concentrated to ca. 3 mL and added to stirred
diethyl ether (40 mL) to produce a red precipitate. The powder
was filtered and washed with diethyl ether, to give the product 7c
(0.09 g, 87% yield). Anal. Calcd for C63H55I3P2Ru: C, 55.81; H,
3
1H, trans dCH2), 5.29 (d, JHH ) 9.6 Hz, 1H, cis dCH2), 4.47
2
(br. s, 1H, CH), 3.30, 3.10 (m, 2H, CH2), 2.71, 2.53 (two d, JHH
) 13.8 Hz, 2H, CH2), 2.12, 1.88 (two d, 2JHH ) 11.9 Hz, 2H, CH2),
2.05-1.65 (m, 15H, PEt3, CH3), 1.22-1.05 (m, PEt3). 13C NMR
(CDCl3): δ 346.3 (t, 2JPP ) 14.8 Hz, CR), 126.9 (Cꢀ), 140.2-121.0
(Ph), 138.5 (dCH), 116.8 (dCH2), 89.5 (Cp), 71.3 (C-Cl), 61.5
(C(bridgehead)), 53.2 (C(CH3)), 40.6 (CH), 47.9 (CH2), 39.5 (CH2),
35.8 (CH2), 23.2-22.4 (PEt3, CH3), 8.49-8.45 (PEt3). 31P NMR
1
4.09. Found: C, 55.91; H, 4.24. H NMR (CDCl3): δ 7.87 (d, 1H,
3JHH ) 7.5 Hz, Ph), 7.52-6.78 (m, 37H, Ph), 5.26 (s, 5H, Cp),
4.24 (br s, 1H, CH), 4.12 (br s, 1H, CH), 2.73 (m, 1H,, CH2),
2.49-2.37 (m, 2H, CH2, CH2), 1.86-1.62 (m, 3H, CH2, CH, CH2),
2
(CDCl3): δ 38.08, 37.62 (two d, JPP ) 33.8 Hz, PEt3). MS: m/z
747.3 (M+).
3
1.19 (t, 3H, JHH ) 7.1 Hz, CH3), 0.97 (m, 1H, CH2). 13C NMR
2
Preparation of Complex 7a. Complex 5a (0.10 g, 0.11 mmol)
and KPF6 (0.06 g, 0.34 mmol) were added into a Schlenk flask,
and CH2Cl2 (10 mL) was then added under nitrogen. To the
resulting solution was added allyl iodide (0.05 mL, 0.53 mmol),
and this mixture was stirred for 12 h at room temperature. The
solvent was removed in vacuo, and CH2Cl2 (2 × 5 mL) was used
to extract the product. The resulting solution was concentrated to
ca. 5 mL and added to stirred diethyl ether (60 mL) to produce a
dark yellow precipitate. The powder was filtered, washed with
diethyl ether, and identified as 7a (0.11 g, 89% yield). Anal. Calcd
for C63H51I3P2Ru: C, 55.97; H, 3.80. Found: C, 55.93; H, 3.84. 1H
(CDCl3): δ 354.4 (t, JPC ) 15.2 Hz, CR), 145.7-123.3 (Ph,
anthracene), 120.4 (Cꢀ), 93.6 (Cp), 59.3 (C(bridgehead)), 48.5 (CH),
46.3 (CH(bridgehead)), 45.7 (CH), 32.8 (CH2), 32.3 (CH2), 26.1
(CH2), 16.6 (CH3). 31P NMR (CDCl3): δ 43.11, 41.80 (2 d, 2JPP
)
27.5 Hz). MS: m/z 975.3 (M+).
Preparation of Complex 7e. Allyl bromide was dried by
washing with saturated NaHCO3 aqueous solution and then was
fractionally distilled from anhydrous MgSO4. The dried reagent
should be protected from strong light. To a Schlenk flask containing
complex 5e (0.12 g, 0.12 mmol), KPF6 (0.06 g, 0.34 mmol), and
CH2Cl2 (10 mL) was added dried allyl bromide (0.10 mL, 0.60
mmol), and the mixture was stirred for 8 h at room temperature.
Then the solvent was removed in vacuo, and CH2Cl2 (2 × 5 mL)
3
NMR (CDCl3): δ 8.47 (d, 1H, JHH ) 8 Hz, Ph), 7.36-6.94 (m,
37H, Ph), 5.27 (s, 5H, Cp), 4.72 (br s, 1H, CH), 4.29 (br s, 1H,

Intramolecular Diels-Alder Reactions in Ru Complexes
Organometallics, Vol. 28, No. 6, 2009 1871
was used to extract the product. The resulting solution was
concentrated to ca. 5 mL and added to stirred diethyl ether (60
mL) to produce the red precipitate 6e, which was filtered and
washed with diethyl ether. A solution of this red powder 6e (0.10
g, 0.09 mmol) in CH2Cl2 (15 mL) was heated to reflux for 6 days.
Then the solution was concentrated to ca. 3 mL and added to diethyl
ether (40 mL) to produce a red precipitate, which was filtered and
washed with diethyl ether to give the product 7e (0.08 g, 82% yield).
Anal. Calcd for C65H57F6P3Ru: C, 68.12; H, 5.01. Found: C, 67.91;
(m, 1H, CHdCH2), 5.14 (d, 3JHH ) 17.0 Hz, 1H, trans CHdCH),
3
5.05 (d, JHH ) 9.4 Hz, 1H, cis CHdCH), 4.93 (m, 1H, CH),
2.98-2.86 (m, 2H, CH2), 1.89-1.38 (m, 12H, CH2), 0.91-0.67
2
(m, 18H, CH3). 13C NMR (CDCl3): δ 345.21 (t, JPP ) 15.1 Hz,
CR), 135.85-123.80 (anthracene), 135.71 (dCH2), 117.75 (dCH),
116.68 (Cꢀ), 89.54 (Cp), 41.36 (C-anthracene), 31.52 (CH2),
22.59-21.33 (PCH2), 8.00-7.42 (CH3). 31P NMR (CD3COCD3):
2
δ 38.41, 38.15 (2 d, JPP ) 32.3 Hz, PEt3). MS: m/z 693.6 (M+).
Preparation of {[Ru]dCdCHCH(C14H9)CH2CH2CHdCH2}-
[BF4] (8e). A dilute solution of HBF4 · Et2O in diethyl ether was
added dropwise at -20 °C to a stirred solution of 5e (0.11 g, 0.11
mmol) in 20 mL of diethyl ether. Immediately, an insoluble solid
precipitated, but the addition was continued until no further
solid was formed. The solution was then decanted, and the brown
solid was washed with diethyl ether (3 × 5 mL) and dried in vacuo
to yield 8e (0.10 g, 86%). Anal. Calcd for C62H53BF4P2Ru: C, 71.06;
3
H, 4.94. 1H NMR (CDCl3): δ 7.89 (d, 1H, JHH ) 7.6 Hz,
anthracene), 7.42-6.77 (m, 38H, Ph), 5.86 (m, 1H, dCH), 5.19
(s, 5H, Cp), 5.08 (d, 1H, 3JHH ) 10.3 Hz, cis dCH2), 5.02 (d, 1H,
3JHH ) 17.3 Hz, trans dCH2), 4.21 (br s, 1H, CH), 2.76 (m, 1H,
CH2), 2.44 (m, 1H, CH2), 2.40 (m, 1H, CH2), 2.32 (m, 2H, CH2),
1.82 (m, 1H, CH), 1.74 (t, 1H, 3JHH ) 12.6 Hz, CH), 1.58 (m, 2H,
2
CH2), 0.96 (m, 1H, CH2). 13C NMR (CDCl3): δ 355.4 (t, JPC
)
1
16.0 Hz, CR), 137.7 (dCH), 145.6-120.4 (Ph, anthracene), 129.8
(Cꢀ), 115.5 (dCH2), 90.7 (Cp), 58.7 (C(bridgehead)), 46.7 (CH2),
H, 5.10. Found: C, 70.98; H, 5.12. H NMR (CDCl3): δ 8.77 (d,
1H, 3JHH ) 9.3 Hz, anthracene), 8.50 (s, 1H, anthracene), 8.11 (d,
45.3 (CH), 34.7 (CH2), 32.7 (CH2, CH2, CH, CH(bridgehead)). 31
P
1H, JHH ) 8.3 Hz, anthracene), 8.06 (d, 1H, JHH ) 9.3 Hz,
3
3
2
3
NMR (CDCl3): δ 43.52, 39.45 (2 d, JPP ) 26.7 Hz). MS: m/z
anthracene), 7.75 (t, 1H, JHH ) 7.2 Hz, anthracene), 7.57 (t, 1H,
1001.3 (M+).
3JHH ) 7.1 Hz, anthracene), 7.48-6.61 (m, 33H, Ph, anthracene),
5.79 (m, 1H, dCH), 5.43 (m, 1H, CH), 5.23 (m, 1H, dCꢀH), 4.99
Preparation of {[Ru]dCdCHCH(9-Cl-10-C14H8)CH2CH2-
CHdCH2}[BF4] (8). A dilute solution of HBF4 · Et2O in diethyl
ether was added dropwise at -20 °C to a stirred solution of 50
(0.10 g, 0.10 mmol) in 20 mL of diethyl ether. Immediately, an
insoluble solid precipitated but the addition was continued until
no further solid was formed. The solution was then decanted, and
the brown-green solid was washed with diethyl ether (3 × 5 mL)
and dried in vacuo to yield 8 (0.09 g, 84% yield). Anal. Calcd for
C62H52BClF4P2Ru: C, 68.80; H, 4.84. Found: C, 68.72; H, 4.88.
1H NMR (CDCl3): δ 8.87 (d, 1H, 3JHH ) 9.1 Hz, anthracene), 8.72
3
3
(d, 1H, JHH ) 9.3 Hz, cis dCH2), 5.12 (d, 1H, JHH ) 20.3 Hz,
cis dCH2), 4.34 (s, 5H, Cp), 2.18 (m, 3H, CH2), 1.92 (m, 1H, CH2).
31P NMR (CDCl3): δ 44.06, 39.27 (two d, JPP ) 26.7 Hz, PPh3).
2
MS: m/z 961.1 (M+).
X-ray Structure Determination of 7c. A single crystal of 7c
suitable for an X-ray diffraction study was glued to a glass fiber
and mounted on a Nonius Kappa CCD diffractometer. The
diffraction data were collected using 3 kW sealed-tube molybdenum
KR radiation (T ) 295 K). The exposure time was 5 s per frame.
Multiscan absorption correction was applied, and decay was
negligible. Data were processed, and the structures were solved
and refined by the SHELXTL program.15 The structure was solved
using direct methods and confirmed by Patterson methods refining
on intensities of all data to give R1 and wR2 for unique observed
reflections (I > 2σ(I)). Hydrogen atoms were placed geometrically
using the riding model with thermal parameters set to 1.2 times
that for the atoms to which the hydrogen is attached and 1.5 times
that for the methyl hydrogens. A solid-state structure determination
was similarly carried out for 7b. Table 1 gives parameters of the
crystal data and refinement for complexes 7c and 7b.
3
(d, 1H, JHH ) 9.2 Hz, anthracene), 8.61 (d, 1H,3JHH ) 9.1 Hz,
anthracene), 7.74-6.62 (m, 35H, Ph, anthracene), 5.82 (m, 1H,
dCH), 5.48 (m, 1H, CH), 5.28 (m, 1H, dCꢀH), 5.04 (d, 1H, 3JHH
) 10.1 Hz, cis dCH2), 4.99 (d, 1H, 3JHH ) 17.8 Hz, trans dCH2),
4.49 (s, 5H, Cp), 2.26-2.16 (m, 3H, CH2, CH2), 1.93 (m, 1H, CH2).
2
31P NMR (CDCl3): δ 43.71, 39.77 (2 d, JPP ) 26.7 Hz, PPh3).
MS: m/z 995.5 (M+).
Preparation of {[Ru′]dCdC(H)CH(9-Cl-10-C14H8)CH2-
CHdCH2}[PF6] (8′). To a Schlenk flask charged with complex 3′
(0.10 g, 0.23 mmol) and KPF6 (0.13 g, 0.71 mmol) was added
methanol (10 mL) under nitrogen. The resulting solution was stirred
at room temperature, and 10 (0.08 g, 0.27 mmol) was added to the
solution. In 4 h the color changed from yellow to orange. After the
solvent was removed under vacuum, 30 mL of CH2Cl2 was added.
The solution was filtered through Celite, and the volume of the
solution was reduced to 5 mL under vacuum. Then 60 mL of ether
was added to cause precipitation of orange powder. After filtration,
the precipitate was washed with 10 mL of ether twice and then
dried under vacuum to give the product 8′ (0.15 g, 78% yield).
Anal. Calcd for C37H50ClF6P3Ru: C, 53.02; H, 6.01. Found: C,
53.13; H, 6.17. 1H NMR (CD3COCD3): δ 8.91-7.42 (m, 8H,
anthracene), δ 5.19 (s, 5H, Cp), 5.69 (m, 1H, [Ru]dCdCH), 5.80
Acknowledgment. We thank the National Science Council
for financial support.
Supporting Information Available: CIF files giving complete
crystallographic data for 7b and 7c. This material is available free
of charge via the Internet at http://pubs.acs.org.
OM8011294
(15) SHELXTL: Structure Analysis Program, version 5.04; Siemens
Industrial Automation Inc., Madison, WI, 1995.