New Acetylide Migration and Oxygen Transfer Reactions in Ruthenium Complexes Containing an Acetyl-Substituted Cp Ligand

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New Acetylide Migration and Oxygen Transfer Reactions

in Ruthenium Complexes Containing an

Acetyl-Substituted Cp Ligand

Jen-Fuh Liu, Shou-Ling Huang, Ying-Chih Lin,* Yi-Hung Liu, and Yu Wang

Department of Chemistry, National Taiwan University, Taipei, Taiwan 106, Republic of China

Received October 12, 2001

Formation of [η

5

_:η

1

_{-C5H4C(CH3)dC(Ph)C(O)](PPh3)2Ru (3a) from the reaction of (η}

5

-C5H4-COCH3)(PPh3)2

RuCl (2a) with PhCtCH proceeds via the vinylidene intermediate [(η

5

-C5H4-COCH3)(PPh3)2RudCdCHPh]Cl (4a). In this reaction the oxygen atom of the pendant acetyl

group in the cyclopentadienyl ligand of 4a is transferred to CR

of the vinylidene ligand, and

this transfer is accompanied by formation of a CdC bond, giving 3a. Treatment of 2a with

LiCtCPh affords (η

5

_{-C5H4C(CCPh)(OH)CH3)(PPh3)2RuCl (6a), and passing 6a through a}

column packed with alumina also gives 3a. The latter transformation involves a new

migration of an acetylide group from exocyclic C

R

of a substituted cyclopentadienyl ligand

to the Ru center followed by the same oxygen transfer process. The metal acetylide (η

5

-C5H4COCH3)(BINAP)RuCtCPh (5c), resulting from the same migration but with no oxygen

transfer, is isolated when two PPh3

ligands are replaced by BINAP. The structures of

complexes 3a and 6b, a chirophos analogue of 6a, have been determined by X-ray diffraction

analysis.

Introduction

We have previously reported the deprotonation

reac-tion of (cyclopentadienyl)ruthenium vinylidene

com-plexes,

1

_{generating a rare class of cyclopropenyl}

com-plexes. The electrophilic CR

of the vinylidene ligand

facil-itates cyclization via a facile nucleophilic addition of the

neighboring carbanion after deprotonation to afford the

product. It has been demonstrated that nucleophilic

addition of a hydroxyl group to CR

of a vinylidene

com-plex provides access to an oxacarbene, and this has been

employed in the cycloisomerization transformation of

terminal alkynyl alcohol in efficient syntheses of

anti-viral nucleosides, polycyclic ethers, and

oligosaccha-rides.

2

_{Since the chemistry of substituted π-bonded}

cyclopentadienyl

3

_{organometallic complexes continues}

to be of great interest due to their potential importance

in the development of carbon-carbon bond formations

4

and their uses in the syntheses of unsaturated organic

species and organometallic polymers,

5

_{we prepared an}

(acetylcyclopentadienyl)ruthenium chloride complex

6

and carried out the reaction of this chloride with

phen-ylacetylene in order to get a similar cyclopropenyl

com-plex. Surprisingly, in this reaction a new type of oxygen

transfer process is observed. Herein we report this new

reaction where the oxygen atom transfers from the

pendant acetyl group of the acetylcyclopentadienyl

lig-and to the vinylidene liglig-and. Such a transfer is followed

by a carbon-carbon bond formation between the

vi-nylidene and the pendant unit of the

acetylcyclopenta-dienyl ligands to yield a new metal acyl complex. Also

reported is a novel acetylide migration reaction found

during our investigation into the mechanism of the

oxygen transfer reaction.

(1) (a) Ting, P. C.; Lin, Y. C.; Lee, G. H.; Cheng, M. C.; Wang, Y. J.

Am. Chem. Soc. 1996, 118, 6433. (b) Lo, Y. H.; Lin, Y. C.; Lee, G. H.;

Wang, Y. Organometallics 1999, 18, 982.

(2) McDonald, F. E. Chem. Eur. J. 1999, 5, 3103.

(3) (a) Chu, H. S.; Lau, C. P.; Wong, K. Y.; Wong, W. T.

Organome-tallics 1998, 17, 2768. (b) Philippopoulos, A. I.; Hadjiliadis, N.; Hart,

C. E.; Donnadieu, B.; McGowan, P. C.; Poilblanc, R. Inorg. Chem. 1997,

36, 1842. (c) Achar, S.; Immoos, C. E.; Hill, M. G.; Catalano, V. J. Inorg. Chem. 1997, 36, 2314. (d) Broussier, R.; Laly, M.; Perron, P.;

Gauth-eron, B.; M’Koyan, S.; Kalck, P.; Wheatley, N. J. Organomet. Chem.

1999, 574, 267. (e) Christie, S. D. R.; Man, K. W.; Whitby, R. J.; Slawin,

A. M. Z. Organometallics 1999, 18, 348. (f) Gallagher, M.; Dougherty, P.; Tanner, P. S.; Barbini, D. C.; Schulte, J.; Jones, W. E., Jr. Inorg.

Chem. 1999, 38, 2953. (g) Collin, J.; Giuseppone, N.; Van de Weghe,

P. Coord. Chem. Rev. 1998, 178-180 (Part 1), 117. (h) Mu, Y.; Piers, W. E.; MacQuarrie, D. C.; Zaworotko, M. J. Can. J. Chem. 1996, 74, 1696. (i) Trouve, G.; Laske, D. A.; Meetsma, A.; Teuben, J. H. J.

Organomet. Chem. 1996, 511, 255. (j) Spence, R. E. V. H.; Piers, W. E. Organometallics 1995, 14, 4617. (k) Horton, A. D. Organometallics

1992, 11, 3271.

(4) (a) Ferrocenes; Hayashi, T., Togni. A., Eds.; VCH: Weinheim, Germany, 1995. (b) Transition Metals for Organic Synthesis: Beller, M., Bolm, C., Eds.; Wiley-VCH: Weinheim, Germany, 1998. (c) Spindler, F.; Pugin, B.; Jalett, H. P.; Buser, H. P.; Pittelkow, U.; Blaser, H. U. Chem. Ind. 1996, 68, 153. (d) Blaser, H.-U.; Spindler, F. In

Comprehensive Asymmetric Catalysis; Jacobsen. E. N., Pfaltz, A.,

Yamamoto, I.-I., Eds.; Springer: Berlin, 1999; Vol. 3, p 1427. (e) Imwinkelried, R. Chimia 1997, 51, 300. (f) Lee, D.-H.; Patel, B. P.; Clot, E.; Eisenstein, O.; Crabtree, R. H. Chem. Commun. 1999, 297.

(5) Nguyen, P.; Go´mez-Elipe, P.; Manners, I. Chem. Rev. 1999, 99, 1515.

(6) (a) Gassman, P. G.; Winter, C. H. J. Am. Chem. Soc. 1988, 110, 6130. (b) Watanabe, M.; Iwamoto, T.; Sano, H.; Kubo, A.; Motoyama, I. J. Organomet. Chem. 1992, 441, 309. (c) Suzuki, H.; Kakigano, T.; Fukui, H.; Tanaka, M.; Moro-oka, Y. J. Organomet. Chem. 1994, 473, 295.

Scheme 1

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Results and Discussion

Preparation of Acetylcyclopentadienyl

Com-plexes. The literature method

7

_{for the preparation of a}

ruthenium chloride complex with an

acetylcyclopenta-dienyl ligand is modified to give the desired product in

a higher yield. Hydrated ruthenium trichloride, RuCl3

‚

xH

2O, in ethanol is added to a heated solution of

acetyl-cyclopentadiene

8

_{and PPh3}

_{in ethanol/ether (4:1), and}

the solution turns red in about 2 h. The deep red product

obtained from this solution is identified as (η

5

-C5H4-COCH3)(PPh3)2RuCl (2a). Complex 2a is soluble in

CHCl

3

, CH

2

Cl

2

, and acetone and insoluble in CH

3

OH,

ether, and hexane.

1

_{H and}

31

_{P NMR data of 2a are}

consistent with the literature values.

7

_{In addition, in}

the

13

_{C NMR spectrum of 2a the resonance attributable}

to the carbonyl carbon appears at δ 197.1. Similar

complexes (η

5

_{-C5H4COCH3)(L-L)RuCl (L-L )}

(2S,3S)-(-)-Ph2PCHMeCHMePPh2, 2b; L-L ) (R)-(+)-BINAP,

2c; L-L ) dppe, 2d) are prepared from the reaction of

2a with the corresponding bidentate phosphines under

various reaction conditions. The

13

_{C NMR resonances}

of the acyl carbon in these complexes all appear at δ

197 ( 1. The chemical shifts of two

31

_{P NMR resonances}

of the bidentate chiral phosphine ligands in 2b (δ 81.11,

68.85) and 2c (δ 49.21, 39.55) are significantly different.

Reaction of Phenylacetylene with 2. The reaction

of 2a with PhCtCH in MeOH at 64 °C for 4 h proceeds

via a somewhat complicated and unprecedented process

to afford [η

5

_:η

1

_-C

5

H

4

C(CH

3)dC(Ph)C(O)](PPh3

)

2

Ru (3a)

in 86% yield (see Scheme 2). The

13

_{C NMR spectrum of}

3a displays a triplet resonance at δ 247.7 with J

C-P

)

12.5 Hz, indicating the presence of a metal acyl carbon.

9

This

13

_{C resonance shifts significantly downfield from}

that (δ 197.1) of the acetyl unit of 2a. The triplet pattern

resulting from coupling with two phosphine atoms is

consistent with the presence of a metal acyl group. Two

resonances at δ 168.1 and 142.3 are assigned to two

olefinic carbon atoms of the pendant chain. The

1

_{H NMR}

spectrum of 3a displays a singlet resonance at δ 2.12,

assignable to the methyl group. From an HMBC

(het-eronuclear multiple bond connectivity) 2D NMR

spec-trum,

10

_{long-range C-H couplings of this methyl proton}

are revealed by three cross-peaks of this

1

_{H resonance,}

showing correlation with the

13

_{C resonances at δ 168.1,}

142.3, and 247.7 assignable to two olefinic carbons and

the acyl carbon, respectively. These data reveal that the

methyl group remains attached in the substituted Cp

ligand and is also bonded to the added portion derived

from phenylacetylene. In the

31

_{P NMR spectrum, the}

singlet resonance at δ 49.13 is assigned to the PPh3

ligand. Two IR absorption peaks at 1772 and 1681 cm

-1

are assigned to the CdO and CdC stretching,

respec-tively. We have carried out reactions of phenylacetylene

with the similar complexes 2b, 2c, and 2d, yielding 3b

(81%), 3c (72%), and 3d (65%), respectively. These

reactions all give complexes of the same type.

Charac-teristic

13

_{C resonances at δ 250 ( 8 are all observed for}

these complexes. All

31

_{P NMR resonances of 3 shift}

toward a downfield region relative to those of their

corresponding chloride complexes 2.

Spectroscopic data for 3 mentioned above are not

sufficient for making a full assignment of the structure.

Attempts were thus made to search for reaction

inter-mediates. We noticed that, during the course of the

reaction of 2a with PhCtCH, the color of the mixture

changed from deep red to orange and then to yellow. A

reaction, carried out in an oil bath at 50 °C, was thus

stopped in 3 h, while the color of the mixture was

orange. From the mixture, the intermediate 4a, showing

a singlet

31

_{P NMR resonance at δ 42.87, was observed}

along with 3a in a 1:1 ratio. This intermediate

trans-formed to 3a quantitatively at the reflux temperature

of MeOH. Attempted column chromatographic

separa-tion of the mixture by using a silica gel packed column

caused decomposition of the intermediate and gave only

3a. The structure of the intermediate was thus deduced

spectroscopically. The

31

_{P NMR resonance of this}

inter-mediate at δ 42.87 is nearly that of a Ru vinylidene

complex.

11

_The

1

_{H NMR resonance at δ 4.74 also}

resembles that of a vinylidene terminal proton.

12

_{It is}

known that metal acetylide can be readily prepared

from deprotonation of a metal vinylidene containing a

terminal proton. We therefore carried out the reaction

of 2a with phenylacetylene in the presence of sodium

methoxide. This reaction gave 3a and the expected

acetylide complex (η

5

_{-C5H4COCH3)(PPh3)2RuCtCPh}

(5a) in a 1:2 ratio. Complex 5a is characterized by its

31

_{P NMR spectrum, showing a singlet resonance at δ}

51.85 for phosphine ligands. The FAB mass spectrum

displays the parent peak at m/z 692.3, corresponding

(7) Reventos, L. B.; Alonso, A. G. J. Organomet. Chem. 1986, 309, 179.

(8) (a) Grundke, G.; Hoffmann, H. M. R. J. Org. Chem. 1981, 46, 5428. (b) Hart, W. P.; Macomber, D. W.; Rausch, M. D. J. Am. Chem.

Soc. 1980, 102, 1196.

(9) Lehmkuhl, H.; Schwickardi, R.; Mehler, G.; Krueger, C.; God-dard, R. Z. Anorg. Allg. Chem. 1991, 606, 141.

(10) Willker, W.; Leibfritz, D.; Magn. Reson. Chem. 1995, 33, 632. (11) Lomprey, J. R.; Selegue, J. P. Organometallics 1993, 12, 616. (12) (a) Trost, B. M.; Kulawiec, R. J. J. Am. Chem. Soc. 1992, 114, 5579. (b) Bruce, M. I.; Hinterding, P.; Tiekink, E. R. T. J. Organomet.

Chem. 1993, 450, 209. Scheme 2

(3)

to cleavage of the acetylide and the acetyl fragments.

On the basis of these data, it is reasonable to assume

that the initial step of the reaction of 2 with HCtCPh,

in the presence of MeONa, possibly proceeds via

addi-tion of phenylacetylene to the Ru metal center followed

by deprotonation to give 5a. We therefore believe that

the intermediate isolated in the absence of sodium

methoxide is [(η

5

_-C

5

H

4

COCH

3

)(PPh

3

)

2RudCdCHPh]Cl

(4a), shown in Scheme 3. In the presence of acid, 5a

readily turned to 3a, possibly also via 4a.

To establish the solid-state structure of 3a, an X-ray

diffraction study was carried out on a single crystal of

3a recrystallized from n-hexane. This complex

crystal-lizes in the orthorhombic space group Pnma with four

molecules in a unit cell. The molecule possesses a mirror

plane. An ORTEP drawing is shown in Figure 1;

symmetry-generated atoms are indicated with the suffix

A, and selected bond distances and angles are listed in

Table 1. The molecule of 3a lies on a mirror plane with

a distorted-tetrahedral metal center. The environment

about the ruthenium metal center consists of the

π-bound Cp ring with its pendant chain bound also to

the metal through the acyl unit and two

triphenylphos-phine ligands. The Ru-C1 distance of 2.009(5) Å is a

normal Ru-C single-bond distance for a metal acyl

group. The C2-C3 bond length of 1.339(6) Å is typical

of a CdC double bond.

Mechanism of Oxygen Transfer. Formation of 3a

can be accounted for by the mechanism depicted in

Scheme 3. The reaction of 2a with phenylacetylene first

yields the cationic vinylidene complex 4a with chloride

as its counteranion. It is well-known that CR

of a

vinylidene ligand is susceptible to nucleophilic attack,

13

particularly by a nitrogen or an oxygen donor, to give a

Fischer type carbene complex. This is exceptionally

facile when the nucleophilic attack is assisted by an

intramolecular chelation. In our system, the oxygen

atom of the pendant acetyl unit in the cyclopentadienyl

ligand nearby serves as a nucleophile, giving A (see

Scheme 3). This cation is stabilized not only by

delo-calizing the cationic charge in the Cp substituent but

also by a significant contribution of the electron-rich

ruthenium bisphosphine group via η

6

_{-complexation and}

possibly by a neighboring group participation of the

vinyl group. Electron donation from the neighboring

vinyl group to the carbenium center causes

carbon-carbon bond formation. Thus, the nucleophilic attack

is followed by formation of a C-C bond and subsequent

deprotonation generates the product 3a. The presence

of NaOMe causes deprotonation of the vinylidene

in-termediate 4a to occur to give the acetylide complex 5a.

An oxygen atom transfer from niobium ketene to

iso-cyanide or nitrile, yielding a niobium vinylidene

com-plex, has been reported.

14

Acetylide Addition to the Acetyl Group of the

Cp Ligand. In an attempt to prepare the acetylide

complex 5a, we carried out the reaction of 2a with 3

equiv of LiCtCPh in CH2

Cl

2

. Surprisingly, the reaction

did not give the expected product but instead generated

(η

5

_-C

5

H

4

C(CCPh)(OH)CH

3

)(PPh

3

)

2

RuCl (6a) in

moder-ate yield (see Scheme 2) and, interestingly, the reaction

in the presence of air gave a higher yield than that in

the absence of air. If the reaction in CH2Cl2

was carried

out under nitrogen, 6a and many unidentified products

(13) (a) Slugovc, C.; Mereiter, K.; Schmid, R.; Kirchner, K.

Orga-nometallics 1998, 17, 827. (b) Bianchini, C.; Casares, J. A.; Peruzzini,

M.; Romerosa, A.; Zanobini, F. J. Am. Chem. Soc. 1996, 118, 4585. (c) Bianchini, C.; Peruzzini, M.; Romerosa, A.; Zanobini, F.

Organome-tallics 1995, 14, 3152. (d) Barrett, A. G. M.; Carpenter, N. E. Organometallics 1987, 6, 2249. (e) Quzzine, K.; Le Bozec, H.; Dixneuf,

P. H. J. Organomet. Chem. 1986, 317, C25. (f) Nombel, P.; Lugan, N.; Mathieu, R. J. Organomet. Chem. 1995, 503, C22.

(14) Fermin, M. C.; Bruno, J. W. J. Am. Chem. Soc. 1993, 115, 7511. Figure 1. ORTEP drawing of [η5_:η1_-C

5H4C(CH3

)dC(Ph)C-(O)](PPh3)2Ru (3a), with thermal ellipsoids shown at the

30% probability level.

Scheme 3

Table 1. Selected Bond Distances (Å) and Angles (deg) of [η5_:η1_-C 5H4C(CH3)dC(Ph)C(O)](PPh3)2Ru (3a) Ru-P1 2.3111(9) Ru-C1 2.009(5) C1-O1 1.226(5) C1-C2 1.556(6) C2-C3 1.339(6) C2-C5 1.488(6) C3-C4 1.506(6) C3-C9 1.495(6) P1-Ru-P1A 104.02(4) P1-Ru-C1 92.59(8) Ru-C1-C2 112.7(3) Ru-C1-O1 131.8(3) C2-C1-O1 115.5(4) C1-C2-C3 118.0(4) C1-C2-C5 116.4(4) C3-C2-C5 125.6(4) C2-C3-C4 126.6(4) C2-C3-C9 116.2(4) C4-C3-C9 117.2(4) C3-C9-C10 125.3(2)

(4)

were obtained. This reaction carried out in THF also

gave a mixture of products. Nucleophilic addition takes

place at the acetyl group, forming a propargylic alcohol

group at the Cp ligand. Triphenylphosphine oxide was

also observed as a byproduct in this reaction, and 6a

was purified by recrystallization from a mixture of

n-hexane and CH

2Cl2. Complex 6a in solution is

un-stable and decomposes to give OPPh3

as the only

identifiable product at room temperature, but a solid

sample could be stored for 2 days at room temperature.

In the

31

_{P NMR spectrum of 6a two doublet resonances}

at δ 39.0 and 38.2 with JP-P

) 41.4 Hz indicates the

presence of a stereogenic center in the complex. The

hydroxy proton appears as a broad singlet resonance

at δ 6.27 in the

1

_{H NMR spectrum, and this proton}

readily exchanges with deuterium in the presence of

D2O. These spectroscopic data as well as a crystal

structure determination of a similar complex described

below firmly establish the structure of the nucleophilic

addition product. Complexes 6b, 6c, and 6d were

similarly prepared from the reaction of LiCtCPh with

2b, 2c, and 2d, respectively, in high yields. For the

formation of 6b and 6c from 2b and 2c, the

diastereo-selectivities are 32% and 24%, respectively. The lower

diastereoselectivity in this system relative to that

observed in the chromium tricarbonyl system

15

_{is not}

unexpected, since the chiral phosphine ligand is

rela-tively farther away from the reactive center.

Single crystals of 6b were obtained by

recrystalliza-tion from n-hexane/acetone, and the molecular structure

was determined by an X-ray diffraction analysis. An

ORTEP drawing is shown in Figure 2, and selected bond

distances and angles are listed in Table 2. The

environ-ment about the ruthenium metal center consists of a

π-bound Cp ring, a chlorine atom, and a chirophos

ligand. The acetylide group is bonded to the exocyclic

CR

of the Cp ligand. The pendant chain is in line with

the less hindered Cl ligand. The Ru-Cl distance of

2.468(1) Å is a normal Ru-Cl single-bond distance. The

C3-C4 bond length of 1.211(9) Å is typical of a CtC

triple bond.

A New Acetylide Migration. Transformation of 6a

to 3a readily occurred in methanol (see Scheme 2).

When 6a was passed through a column packed with

activated alumina or when a solution of 6a was stirred

in the presence of MeONa or CF3COOH, the same

transformation occurred, but with much lower yield, and

several intractable products were also observed. A new

acetylide migration followed by the oxygen transfer

mentioned above accounts for the transformation of 6a

to 3a. The phenylacetylide group migrates from the

exocyclic CR

of the substituted Cp ligand to the Ru metal

center. This is followed by formation of a vinylidene

complex via protonation, and then the oxygen transfer

mentioned above takes place to give the final product

3a. The acetylide migration process could be assisted

by dissociation of the chloride ligand in methanol. The

presence of the electron-rich CtC triple bond of the

propargylic group could provide yet another stabilization

effect via coordination to the metal center to give the

final product. Treatment of 6c with alumina resulted

in the formation of 5c. In this system, the vinylidene

complex 4c could be prepared by protonation of 5c with

CF3COOH. Complex 4c decomposed to several

uniden-tified products at room temperature. The oxygen

trans-fer product was observed only as a minor product.

Interestingly, when 6d was subjected to

chromatog-raphy on an alumina-packed column, dehydration was

observed, yielding [η

5

_{-C5H4C(dCH2)CCPh](dppe)RuCl}

(7d), which was identified by spectroscopic methods.

Two vinylic protons give two singlet resonances at δ 5.46

and 5.59 in the

1

_{H NMR spectrum. Both correlate to}

the

13

_{C resonance at δ 118.3 in the 2D NMR HMQC}

spectrum and to

13

_{C resonances at δ 94.6 (quaternary}

carbon on Cp) and δ 88.9 and 89.2 (two acetylene

carbons) in the 2D NMR HMBC spectrum. The

31

_{P NMR}

spectrum displays a singlet resonance at δ 79.66,

indicating the lack of a stereogenic center. For the

ferrocenyl carbocation, it is known that nucleophilic

addition reactions often proceed in competition with

deprotonation.

16

_{The reaction of 7d with CF3COOH gave}

a carbenium ion product (8d) showing a two-doublet

pattern at δ 86.46 and 73.93 (JP-P

) 24.1 Hz) in the

31

_{P NMR spectrum. Protonation presumably occurs at}

the exocyclic C

β

,

17

and the restricted rotation of the

exocyclic group originating from the neighboring group

participation of the metal satisfactorily accounts for the

planar chirality. Deprotonation of this unstable

carbe-nium product, which does not undergo acetylide

migra-tion, in the presence of some weak nucleophiles readily

gives back 7d. Reversed migration of an acetylide group

(15) Netz, A.; Polborn, K.; Mu¨ ller, T. J. J. J. Am. Chem. Soc. 2001,

123, 3441.

(16) Bunton, C. A.; Crawford, W.; Watts, W. E. Tetrahedron Lett.

1977, 3755.

(17) (a) Pittman, C. U., Jr.; Olah, G. A. J. Am. Chem. Soc. 1965, 87, 5632. (b) Olah, G. A.; Spear, R. J.; Westerman, P. W.; Denis, J.-M. J.

Am. Chem. Soc. 1974, 96, 5855. Figure 2. ORTEP drawing of [η5_-C

5H4C(OH)(CCPh)CH3

]-(Chiraphos)RuCl (6b), with thermal ellipsoids shown at the 30% probability level.

Table 2. Selected Bond Distances (Å) and Angles (deg) of [(η5_-C 5H4C(CCPh)(OH)CH3)](Chiraphos)RuCl (6b) Ru-P1 2.2899(12) Ru-C1 2.4680(11) Ru-P2 2.3392(13) C1-C11 1.529(9) C1-C2 1.573(9) C1-C3 1.508(9) C1-O1 1.445(7) C3-C4 1.211(9) P1-Ru-P2 82.86(4) C3-C1-C2 110.0(5) P1-Ru-Cl 86.21(4) C1-C3-C4 175.4(7) P2-Ru-Cl 95.12(4) C3-C4-C5 178.8(6) C11-C1-C2 109.1(6) C1-C11-C15 125.8(5) O1-C1-C2 105.4(5) C1-C11-C12 125.7(5) O1-C1-C3 110.8(5) C15-C11-C12 108.3(5)

(5)

from an Fe metal to a cyclopentadienyl ligand has been

reported recently.

18

_{In our system the migration is from}

the exocyclic CR

of a substituted group on the Cp ligand

to the metal.

Concluding Remarks. A new oxygen transfer

reac-tion from an acetyl group on a substituted

cyclopenta-dienyl ligand to a coordinated vinylidene ligand was

observed in the reaction of 2 with phenylacetylene,

giving 3. The reaction proceeds via addition of

phenyl-acetylene to the ruthenium metal center to yield the

vinylidene ligand. The proximity of the acetyl group and

the vinylidene ligand and the electrophilicity of CR

of

the vinylidene ligand promote such an oxygen transfer

process and facilitate CdC bond formation. In the

presence of MeOH, complex 6a undergoes a new

acetyl-ide migration from exocyclic CR

of the substituted Cp

ligand to the Ru metal center to yield 3a. The migration

is possibly assisted by dissociation of the chloride ligand

in 6a and is followed by formation of a similar

vi-nylidene complex in which oxygen transfer takes place

to give the final product 3a. Possible applications of such

a reaction in synthesizing new organometallic complexes

are currently under investigation.

Experimental Section

General Procedures. Unless mentioned otherwise, all

manipulations were performed under nitrogen using vacuum-line, drybox, and standard Schlenk techniques. CH2Cl2was

distilled from CaH2, and diethyl ether and THF were distilled

from Na/benzophenone. All other solvents and reagents were of reagent grade and were used as received. NMR spectra were recorded on Bruker AM-300WB and DMX-500 spectrometers at room temperature (unless stated otherwise). Chemical shifts are given in δ and referenced to TMS. FAB mass spectra were recorded on a JEOL SX-102A spectrometer. Αcetylcyclopen-tadienide was prepared according to the methods reported in the literature.19_RuCl

3‚xH2O was purchased from Strem

Chemi-cals. Elemental analyses and X-ray diffraction studies were carried out at the Regional Center of Analytical Instrument located at the National Taiwan University.

Preparation of (η5_{-C5H4COCH3)(PPh3)2RuCl (2a). A}

solution of sodium acetylcyclopentadienide (18.0 g) in HCl aqueous solution (1.0 N, 500 mL) was stirred for 30 min. The acetylcyclopentadiene was extracted with 4× 25 mL of diethyl ether and dried over MgSO4, and the volume of the ethereal

solution was reduced to ca. 10 mL. PPh3(8.0 g, 30.5 mmol)

and 40 mL of absolute ethanol were added to the ethereal solution, and the mixture was refluxed for 10 min; subse-quently RuCl3‚xH2O (2.4 g, ca. 11.6 mmol) in 20 mL of absolute

ethanol was added to the boiling solution by syringe. The mixture was heated to reflux for another 2 h; the red precipitates thus formed were filtered off and washed with ethanol and n-hexane (5.1 g, 57.2%). The product can be recrystallized from CH2Cl2/n-hexane. Spectroscopic data for 2a

are as follows. IR (CH2Cl2): ν(CdO) 1663 cm-1. 1H NMR

(CDCl3): δ 7.44-7.07 (m, 30H, Ph), 5.09 (br, 2H, Cp), 3.60 (br, 2H, Cp), 2.19 (s, 3H, CH3). 13C NMR (CDCl3): δ 197.1 (s, CdO), 137.5-127.4 (m, Ph), 88.3 (s, Cp), 86.4 (s, Cp), 79.0 (s, Cp), 29.3 (s, CH3).31P NMR (CDCl3): δ 37.96 (s). FAB mass: m/z 768.2 (M+_{), 733.2 (M}+_{- Cl), 471.0 (M}+_{- PPh} 3,Cl). Anal.

Calcd for C43H37OP2RuCl: C, 67.23; H, 4.86, Found: C, 67.40;

H, 4.72.

Preparation of 2b, 2c, and 2d. Preparation of 2b, 2c, and 2d from the reactions of 2a with corresponding free phosphine

ligands followed the procedure given in the literature. For example, complex 2b was obtained from a thermal reaction of

2a with Chiraphos in benzene for 4 h and was purified by

recrystallization from n-hexane/CH2Cl2(10:1) in 95% yield.

Spectroscopic data for 2b (Chiraphos) are as follows.1_{H NMR}

(CDCl3): δ 8.03-7.00 (m, 20H, Ph), 5.30 (br, 1H, Cp), 5.04 (br, 1H, Cp), 4.77 (br, 1H, Cp), 2.99 (br, 1H, Cp), 2.87-2.79 (m, 1H, PCH(CH3)), 2.05-1.94 (m, 1H, PCH(CH3)), 1.69 (s, 3H, CH3), 1.06-1.00 (m, 3H, PCH(CH3)), 0.91-0.85 (m, 3H, PCH-(CH3)).13C NMR (CDCl3): δ 196.9 (s, CdO), 140.3-127.8 (m, Ph), 97.6, 88.2, 83.1, 80.7, 75.8 (s, Cp), 38.2-37.6 (m, PCH-(CH3)), 35.7-35.1 (m, PCH(CH3)), 28.5 (s, CH3), 16.3-15.9 (m, PCH(CH3)), 15.2-14.9 (m, PCH(CH3)).31P NMR (CDCl3): δ 81.11 (d, JP-P ) 42.5 Hz), 68.85 (d, JP-P ) 42.5 Hz). MS

(FAB): m/z 670.1 (M+), 635.1 (M+- Cl). Anal. Calcd for C35H35

-OP2RuCl: C, 62.73; H, 5.26, Found: C, 62.49; H, 4.97.

Complex 2c was obtained similarly from a thermal reaction of 2a with BINAP in toluene for 10 days in 90% yield. Spectroscopic data for 2c are as follows.1_{H NMR (CDCl}

3): δ 7.90-6.15 (m, 32H, Ph), 5.04 (br, 1H, Cp), 4.47 (br, 1H, Cp), 4.22 (br, 1H, Cp), 4.12 (br, 1H, Cp), 2.17 (s, 3H, CH3).13C NMR (CDCl3): δ 197.3 (s, CdO), 143.1-125.4 (m, Ph), 95.3, 89.8, 84.2, 81.6, 77.7 (s, Cp), 29.5 (s, CH3).31P NMR (CDCl3): δ 49.21 (d, JP-P) 54.5 Hz), 39.55 (d, JP-P) 54.5 Hz). MS (FAB): m/z

866.2 (M+), 831.3 (M+- Cl). Anal. Calcd for C51H39OP2RuCl:

C, 70.70; H, 4.54, Found: C, 70.54; H, 4.70.

Preparation of (η5_{-CH3COC5H4)(dppe)RuCl (2d).}20 _A

solution of 0.1 g of Ru(η5_-CH

3COC5H4)Cl(PPh3)2 (2a; 0.13

mmol) and 0.052 g (0.13 mmol) of dppe (1,2-bis(diphenylphos-phino)ethane) in toluene (20 mL) was heated to reflux for 6 h. The volume was reduced to 5 mL, and 20 mL of light petroleum ether was added. The faint yellow precipitates were filtered off, and the filtrate was stored at -5 °C overnight to give the product as orange crystals. Spectroscopic data for 2d are as follows.1_{H NMR (CDCl} 3): δ 7.70-7.10 (m, 20H, Ph), 5.29 (br, 2H, Cp), 4.13 (br, 2H, Cp), 2.72-2.29 (m, 4H, PCH2CH2P), 1.94 (s, 3H, CH3).13C NMR (CDCl3): δ 196.4 (s, CdO), 139.9-127.0 (m, Ph), 88.4, 88.0, 66.2 (s, Cp), 28.1 (s, CH3), 26.7 (t, PCH2CH2P, JC-P) 22.4 Hz).31P NMR (CDCl3): δ 78.86 (s).

MS (FAB): m/z 642.1 (M+), 607.1 (M+- Cl). Anal. Calcd for C33H31OP2RuCl: C, 61.72; H, 4.87. Found: C, 61.74; H, 4.89. Preparation of [η5_η1_{-C5H4C(CH3)dC(Ph)C(O)](PPh3)2Ru} (3a). To a solution of 2a (0.25 g, 0.326 mmol) in MeOH (50

mL) was added HCtCPh (360 µL, 3.25 mmol). The deep red solution was heated to reflux (64 °C) for 4 h. The solution first turned to orange and finally to yellow and, after being cooled, was concentrated to ca. 10 mL; it was then slowly added to 70 mL of a stirred solution of ether. The yellow precipitate thus formed was filtered off and washed with ether. The yellow product was recrystallized from CH2Cl2/ether (1:10) and

identified as complex 3a (0.23 g, 86%). Spectroscopic data for

3a are as follows. IR (cm-1, CH2Cl2): 1772 (s, νCdO), 1681 (w,

νCdC).1H NMR (CDCl3): δ 7.36-7.02 (m, 35H, Ph), 4.67 (br, 2H, Cp), 3.92 (br, 2H, Cp), 2.12 (s, 3H, CH3). 13C NMR (CDCl3): δ 247.7 (t, JC-P) 12.5 Hz, CdO), 168.1 (s, COCPh), 142.3 (s, CCH3), 140.7-124.7 (m, Ph), 126.3, 94.4, 83.3 (s, Cp), 19.3 (s, CH3).31P NMR (CDCl3): δ 49.13 (s). MS (FAB): m/z 834.4 (M+), 572.2 (M+- PPh3), 543.2 (M+- PPh3, CO), 467.1

(M+- PPh3, CO, Ph). Anal. Calcd for C51H42OP2Ru: C, 73.45;

H, 5.08. Found: C, 73.67; H, 4.96.

Preparation of [η5_η1 -C5H4C(CH3)dC(Ph)C(O)](Chira-phos)Ru (3b). To a solution of 2b (100 mg, 0.15 mmol) in

anhydrous MeOH (20 mL) was added phenylacetylene (50 µL, 0.45 mmol), and the mixture was heated to reflux for 3 h. Then the yellow solution was evaporated to dryness, and the residue was recrystallized from CH2Cl2/n-hexane to give a yellow

powder identified as 3b (89 mg, 81% yield). Spectroscopic data are as follows.1_{H NMR (CDCl}

3): δ 7.57-6.49 (m, 25H, Ph),

(18) Liu, L. K.; Chang, K. Y.; Wen, Y. S. J. Chem. Soc., Dalton Trans.

1998, 1, 741.

(19) Rogers, R. D.; Atwood, J. L.; Rausch, M. D.; Macomber, D. W.; Hart, W. P. J. Organomet. Chem. 1982, 238, 79.

(20) Alonso, A. G.; Revento´s, L. B. J. Organomet. Chem. 1988, 338, 249.

(6)

5.61 (br, 1H, Cp), 5.46 (br, 1H, Cp), 4.76 (br, 1H, Cp), 4.64 (br, 1H, Cp), 3.62-3.40 (m, 1H, PCH(CH3)), 2.15-1.99 (m, 1H, PCH(CH3)), 1.91 (s, 3H, CH3), 1.36-1.28 (m, 3H, PCH(CH3)), 0.93-0.88 (m, 3H, PCH(CH3)).13C NMR (CDCl3): δ 257.6 (dd, JC-P) 16.1, 11.7 Hz, CdO), 153.0 (s, COCPh), 143.0 (s, CCH3), 138.2-124.7 (m, Ph), 95.2, 92.5, 91.6, 86.6, 67.8 (s, Cp), 41.5-40.9 (m, PCH(CH3)), 34.1-33.5 (m, PCH(CH3)), 27.4 (s, CH3), 15.3-14.9 (m, PCH(CH3)).31P NMR (CDCl3): δ 93.69 (d, JP-P

) 36.5 Hz), 91.32 (d, JP-P) 36.5 Hz). Anal. Calcd for C43H40

-OP2Ru: C, 70.19; H, 5.48. Found: C, 70.41; H, 5.79. Preparation of [η5_η1 -C5H4C(CH3)dC(Ph)C(O)](R-BI-NAP)Ru (3c). To a suspension of 2c (100 mg, 0.12 mmol) in

anhydrous MeOH (20 mL) was added phenylacetylene (39 µL, 0.36 mmol). The orange solution was heated to reflux for 5 h and subsequently cooled to room temperature. The solvent was removed under vacuum and the residue recrystallized from CH2Cl2/n-hexane to give 3c as a microcrystalline yellow solid

(yield: 81 mg, 72%). Spectroscopic data for 3c are as follows.

1_{H NMR (CDCl} 3): δ 7.66-6.09 (m, 37H, Ph), 5.00, 4.89, 4.37, 3.63 (br, 4H, Cp), 1.96 (s, 3H, CH3).13C NMR (CDCl3): δ 245.7 (dd, JC-P) 10.2, 6.4 Hz, CdO), 168.3 (s, COCPh), 145.6 (s, CCH3), 145.1-127.0 (m, Ph), 94.1, 90.0, 89.0, 87.2, 84.5 (s, Cp), 19.6 (s, CH3).31P NMR (CDCl3): δ 63.36 (d, JP-P) 47.5 Hz), 56.76 (d, JP-P) 47.5 Hz). MS (FAB): m/z 932.3 (M+). Anal.

Calcd for C59H44OP2Ru: C, 76.03; H, 4.76. Found: C, 76.15;

H, 4.87.

Preparation of [η5_η1 -C5H4C(CH3)dC(Ph)C(O)](dppe)-Ru (3d). To a solution of 2d (25 mg, 0.04 mmol) in anhydrous

methyl alcohol (20 mL) was added phenylacetylene (45 µL, 0.40 mmol), and the mixture was heated to reflux for 6 h. Then the yellow solution was evaporated to dryness and the residue was recrystallized with CH2Cl2/n-hexane to give a yellow

powder identified as 3d (15 mg, 65% yield). Spectroscopic data for 3d are as follows.1_{H NMR (CDCl}

3): δ 7.69-6.95 (m, 25H, Ph), 5.59 (br, 2H, Cp), 4.72 (br, 2H, Cp), 2.72-2.29 (m, 4H, PCH2CH2P), 1.82 (s, 3H, CH3).13C NMR (CDCl3): δ 254.9 (t, JC-P) 14.0 Hz, CdO), 167.9 (s, COCPh), 144.1 (s, CCH3), 138.6-125.4 (m, Ph), 92.8, 86.4, 68.8 (s, Cp), 29.7-27.5 (t, PCH2CH2P, JC-P ) 21.4 Hz), 19.8 (s, CH3). 31P NMR

(CDCl3): δ 96.50 (s). MS (FAB): m/z 708.2 (M+). Anal. Calcd

for C41H36OP2Ru: C, 69.58; H, 5.13. Found: C, 69.44; H, 4.98. Spectroscopic Observation of {(η5 -C5H4COCH3)-(PPh3)2RudCdCHPh}Cl (4a). The same reaction was

car-ried out in an oil bath with the temperature maintained at 50 °C for 3 h to give an orange mixture. The solvent of this mixture was removed under vacuum, and the residue was redissolved in CDCl3. The31P NMR spectrum of this solution

indicated formation of the intermediate 4a as well as 3a in a ratio of roughly 1:1. Attempts to isolate 4a by column chro-matography led to decomposition. Only a yellow band, identi-fied as 3a, was obtained. Spectroscopic data for 4a were obtained from the mixture of products.1_{H NMR (CDCl}

3): δ

7.69-6.95 (m, 35H, Ph), 5.03 (br, 2H, Cp), 4.74 (s, 1H, CdCH(Ph)), 4.56 (br, 2H, Cp), 2.28 (s, 3H, CH3).31P NMR

(CDCl3): δ 42.87 (s). Further heating of the mixture in MeOH

converted this intermediate to 3a.

Isolation of (η5_{-C5H4COCH3)(PPh3)2RuCtCPh (5a). In}

the presence of NaOMe (20 mg), the reaction of 2a (0.051 g, 0.064 mmol) with excess HCtCPh (72 µL, 0.65 mmol) in MeOH gave 3a and the acetylide complex 5a in a 1:2 ratio. Column chromatographic separation of the mixture eluted by

n-hexane/CH2Cl2 (1:5) gave two yellow bands, 5a and 3a.

Spectroscopic data of 5a are as follows.1_{H NMR (CDCl} 3): δ

7.30-6.89 (m, 35H, Ph), 4.59 (br, 2H, Cp), 3.80 (br, 2H, Cp), 2.57 (s, 3H, CH3).31P NMR (CDCl3): δ 51.85 (s). MS (FAB):

m/z 834.4 (M+), 692.3 (M+- CCPh, COCH3). In the presence

of CF3COOH, 5a in CDCl3cleanly converted to 3a in a NMR

tube in 4 h. Anal. Calcd for C51H42OP2Ru: C, 73.45; H, 5.08. Preparation of [η5_{-C5H4C(CCPh)(OH)CH3](PPh3)2RuCl}

(6a). To a solution of 2a (102 mg, 0.13 mmol in 10 mL of CH2Cl2) exposed to air was added lithium phenylacetylide (390

µL, 0.39 mmol in 1 M THF). The reaction mixture was stirred

at room temperature for 30 min. Then the solvent was removed under vacuum. The residue was extracted with 1 mL of CH2Cl2, and n-hexane (2 mL) was added to remove the salt

after filtration. Then the solvent was removed under vacuum and the residue recrystallized in two stages from dichlo-romethane/n-hexane to give red crystals of 6a (67 mg, 60% yield); OPPh3(11 mg, 30% yield) was obtained as a byproduct.

Spectroscopic data of 6a are as follows.1_{H NMR (CDCl} 3): δ 7.69-6.97 (m, 35H, Ph), 6.27 (br, 1H, OH), 4.31 (br, 1H, Cp), 4.08 (br, 1H, Cp), 3.73 (br, 1H, Cp), 3.32 (br, 1H, Cp), 1.79 (s, 3H, CH3).13C NMR (CDCl3): δ 138.1-123.4 (m, Ph), 121.1 (chiral carbon), 92.8 (s, CtCPh), 84.2 (s, CtCPh), 73.8, 77.6, 72.8, 77.2, 67.0 (s, Cp), 33.8 (s, CH3).31P NMR (CDCl3): δ 39.01 (d, JP-P) 41.4 Hz), 38.20 (d, JP-P) 41.4 Hz). MS (FAB): m/z 870.1 (M+), 834.2 (M+ - Cl), 733.2 (M+ - Cl, CCPh). A satisfactory elemental analysis was not obtained due to the instability of the complex. The same reaction in THF or in CH2Cl2under nitrogen gave a complicated mixture of products.

Preparation of 6b was similarly carried out using the same procedure. A mixture containing diastereomers of 6b was obtained after purification. No attempt was made to separate these diastereomers. Spectroscopic data for 6b (chiraphos) are as follows. Major product: 1_{H NMR (CDCl}

3) δ 8.05-7.04 (m, 25H, Ph), 5.64 (br, 1H, OH), 5.15 (br, 1H, Cp), 5.07 (br, 1H, Cp), 4.58 (br, 1H, Cp), 4.23 (br, 1H, Cp), 2.63-2.50 (m, 1H, PCH(CH3)), 2.06-1.95 (m, 1H, PCH(CH3)), 1.71 (s, 3H, CH3), 1.03-0.94 (m, 3H, PCH(CH3)), 0.87-0.82 (m, 3H, PCH(CH3)); 13_{C NMR (CDCl} 3) δ 136.5-127.1 (m, Ph), 118.4 (s, chiral carbon), 92.8 (s, CtCPh), 82.8 (s, CtCPh), 81.8, 81.3, 80.8, 72.3, 67.0 (s, Cp), 37.7-36.2 (m, PCH(CH3)), 34.1 (s, CH3), 15.5-14.1 (m, PCH(CH3));31P NMR (CDCl3) δ 85.13 (d, JP-P ) 40.6 Hz), 64.96 (d, JP-P) 40.6 Hz). Minor product: 1H NMR (CDCl3) δ 8.05-7.04 (m, 25H, Ph), 7.14 (br, 1H, OH), 4.70 (br, 1H, Cp), 3.58 (br, 1H, Cp), 3.18 (br, 1H, Cp), 2.58 (br, 1H, Cp), 2.63-2.50 (m, 1H, PCH(CH3)), 2.06-1.95 (m, 1H, PCH(CH3)), 1.80 (s, 3H, CH3), 1.03-0.94 (m, 3H, PCH(CH3)), 0.87-0.82 (m, 3H, PCH(CH3));13C NMR (CDCl3) δ 136.5-127.1 (m, Ph), 118.3 (s, chiral carbon), 93.0 (s, CtCPh), 83.0 (s, CtCPh), 75.9, 74.6, 72.2, 67.5, 66.6 (s, Cp), 37.7-36.2 (m, PCH(CH3)), 31.5 (s, CH3), 15.5-14.1 (m, PCH(CH3));31P NMR (CDCl3) δ 84.30 (d, JP-P) 42.7 Hz), 65.80 (d, JP-P) 42.7 Hz).

Spectroscopic data for 6c (BINAP) are as follows. Major product: 1_{H NMR (CDCl} 3) δ 7.29-6.17 (m, 37H, Ph), 6.24 (br, 1H, OH), 4.33 (br, 1H, Cp), 4.32 (br, 1H, Cp), 4.25 (br, 1H, Cp), 3.46 (br, 1H, Cp), 1.77 (s, 3H, CH3);13C NMR (CDCl3) δ 142.5-119.2 (m, Ph), 118.2 (s, chiral carbon), 92.8 (s, CtCPh), 83.1 (s, CtCPh), 85.0, 81.1, 75.9, 69.3, 66.6 (s, Cp), 31.2 (s, CH3);31P NMR (CDCl3) δ 53.17 (d, JP-P) 52.1 Hz), 37.23 (d, JP-P) 52.1 Hz). Minor product: 1H NMR (CDCl3) δ 7.29-6.17 (m, 37H, Ph), 6.18 (br, 1H, OH), 4.20 (br, 1H, Cp), 3.72 (br, 1H, Cp), 3.59 (br, 1H, Cp), 3.55 (br, 1H, Cp), 1.70 (s, 3H, CH3);13C NMR (CDCl3) δ 142.5-119.2 (m, Ph), 118.0 (s, chiral carbon), 93.2 (s, CtCPh), 83.0 (s, CtCPh), 86.1, 81.4, 72.8, 67.5, 65.4, (s, Cp), 35.5 (s, CH3);31P NMR (CDCl3) δ 53.69 (d, JP-P) 52.3 Hz), 41.67 (d, JP-P) 52.3 Hz); MS (FAB) m/z 968.0 (M+), 932.3 (M+- Cl), 831.3 (M+- Cl, CCPh).

Spectroscopic data for 6d (dppe) are as follows.1_{H NMR}

(CDCl3): δ 8.01-6.96 (m, 25H, Ph), 5.55 (br, 1H, OH), 5.33 (br, 1H, Cp), 5.26 (br, 1H, Cp), 3.88 (br, 1H, Cp), 2.89 (br, 1H, Cp), 2.72-2.31 (m, 4H, PCH2CH2P), 1.87 (s, 3H, CH3). 13C NMR (CDCl3): δ 142.1-23.2 (m, Ph), 116.6 (s, chiral carbon), 92.9 (s, CtCPh), 83.4 (s, CtCPh), 72.6, 79.5, 77.8, 70.0, 67.0 (s, Cp), 33.8 (s, CH3), 27.9-26.5 (m, PCH2CH2P). 31P NMR (CDCl3): δ 80.95 (d, JP-P) 26.4 Hz), 76.43 (d, JP-P) 26.4 Hz). MS (FAB): m/z 744.3 (M+), 727.3 (M+- OH), 708.8 (M+ - Cl), 691.3 (M+ _{- Cl, OH), 607.2 (M}+ _{- Cl, CCPh). Anal.}

Calcd for C43H37OP2RuCl: C, 66.17; H, 5.01. Found: C, 66.35;

H, 5.12.

Transformation of 6a to 3a. Complex 6a (88 mg) was

passed through a column packed with neutral aluminum oxide

(7)

eluted by CH2Cl2. The red band changed to yellow in the

column. The solvent of the yellow fraction collected was removed under vacuum to give 3a (65 mg, 78% yield). This transformation is also observed in CDCl3when NaOMe was

added to a solution of 6a in a NMR tube. The NMR yield was about 50%.

Isolation of (η5_{-C5H4COCH3)(R-BINAP)RuCtCPh (5c).}

Transformation of 6c to 5c was performed by chromatography on an alumina-packed column, and CH2Cl2was used as eluent;

the product was isolated as a yellow solid and was purified by recrystallization from CH2Cl2/n-hexane. Spectroscopic data for 5c are as follows.1_{H NMR (CDCl} 3): δ 7.96-6.20 (m, 37H, Ph), 4.83, 4.68, 4.35, 4.30 (br, 4H, Cp), 2.31 (s, 3H, CH3).13C NMR (CDCl3): δ 197.1 (s, CdO), 150.2-121.5 (m, Ph), 118.3 (t, JC-P ) 22.6 Hz, CtCPh), 114.2 (s, CtCPh), 95.9, 93.4, 88.9, 85.3, 83.9 (s, Cp), 29.0 (s, CH3).31P NMR (CDCl3): δ 57.60 (d, JP-P ) 47.6 Hz), 47.40 (d, JP-P) 47.6 Hz). MS (FAB): m/z 932.3

(M+), 831.2 (M+- CCPh). Anal. Calcd for C59H44OP2Ru: C,

76.03, H, 4.76. Found: C, 76.00; H, 4.67.

Preparation of [(η5_{-C5H4COCH3)(R-BINAP)RudCd} CHPh]CF3COO (4c). A tube was charged with 5c (25 mg,

0.027 mmol), and excess trifluoroacetic acid (CF3COOH) and

chloroform-d were introduced into this tube. The1_{H and}31_P

NMR spectra were collected. Complex 4c transformed to 3c (5% NMR yield) and other intractable products in 20 min at room temperature. No attempt was made to isolate 4c. Spectroscopic data for 4c are as follows.1_{H NMR (CDCl}

3): δ

7.61-6.28 (m, 37H, Ph), 5.79, 5.48, 5.36, 4.97 (br, 4H, Cp), 4.34 (s, 1H, CdCH(Ph)), 2.32 (s, 3H, CH3).31P NMR (CDCl3):

δ 51.92 (d, JP-P) 36.8 Hz), 35.73 (d, JP-P) 36.8 Hz). Preparation of [η5_{-C5H4C(dCH2)CCPh](dppe)RuCl (7d).}

Complex 6d (105 mg, 0.14 mmol) in CH2Cl2 was passed

through an alumina-packed column. The yellow band was eluted with CH2Cl2. The solvent of this yellow band was

removed under vacuum. The product was recrystallized from CH2Cl2/n-hexane to give 7d (62 mg, 60%). Spectroscopic data

for 7d are as follows.1_{H NMR (CDCl}

3): δ 7.89-7.02 (m, 25H, Ph), 5.59 (s, 1H, dCH2), 5.46 (s, 1H, dCH2), 4.98 (br, 2H, Cp), 4.06 (br, 2H, Cp), 2.69-2.64 (m, 2H, PCH2CH2P), 2.49-2.43 (m, 2H, PCH2CH2P).13C NMR (CDCl3): δ 141.8-123.9 (m, Ph), 123.2 (s, C5H4CdCH2), 118.3 (s, C5H4CdCH2), 94.6, 83.7, 74.8 (s, Cp), 89.2 (s, CtCPh), 88.9 (s, CtCPh), 27.7 (t, PCH2CH2P, JC-P) 22.3 Hz).31P NMR (CDCl3): δ 79.66 (s). MS (FAB):

m/z 726.2 (M+), 691.2 (M+ - Cl). Anal. Calcd for C41H35P2

-RuCl: C, 67.81; H, 4.86. Found: C, 67.76; H, 4.81. Protonation of 7d in CDCl3with excess CF3COOH gave a single product

(8d). Spectroscopic data for 8d are as follows. 1_{H NMR}

(CDCl3): δ 7.69-7.12 (m, 25H, Ph), 6.27, 6.11, 5.65, 3.85 (br,

4H, Cp), 3.06-2.76 (m, 4H, PCH2CH2P), 1.26 (s, 3H, CH3).31P

NMR (CDCl3): δ 86.46 (d, JP-P) 24.1 Hz), 73.93 (d, JP-P)

24.1 Hz). FAB mass: m/z 727.4 (M+), 691.8 (M+- Cl).

X-ray Structure Determination of 3a and 6b. For 3a, a

single crystal of dimensions 0.20 × 0.10 × 0.10 mm3_was

mounted on a glass fiber with epoxy. Data were collected at room temperature on a Siemens SMART CCD area detector system employing a 3 kW sealed-tube X-ray source operating at 1.5 kW. Data were collected using a narrow frame method. The total data collection yielded 11 876 data after integration using SAINT. Laue symmetry revealed a orthorhombic crystal system, and unit cell parameters were determined from the least-squares refinement of three-dimensional centroids of 25 unique reflections. Data were corrected for absorption with the SADABS21_{program. The space group was assigned as Pnma}

on the basis of systematic absences and intensity statistics using XPREP, and the structure was solved and refined using direct methods included in the SHELXTL22_{package. For a Z}

value of 4 there is one independent molecule within the asymmetric unit. In the final model, non-hydrogen atoms were refined anisotropically, with hydrogen atoms included in idealized locations. The structure was refined to R1 ) 0.0551 and wR2 ) 0.0798 for all data (R1 ) 0.0330 and wR2 ) 0.0702 for I > 2σ(I)).23_{Fractional coordinates and thermal parameters}

are given in the Supporting Information. The structure de-termination of 6b was similarly carried out on a SMART CCD diffractometer. Relevant data for both crystals are given in Table 3.

Acknowledgment. Financial support from the

Na-tional Science Council of Taiwan is gratefully

acknowl-edged.

Supporting Information Available: Details of the

struc-tural determinations for complex 3a and 6b, including tables of crystal and intensity collection data, positional and aniso-tropic thermal parameters, and all of the bond distances and angles. This material is available free of charge via the Internet at http://pubs.acs.org.

OM010893J

(21) The SADABS program is based on the method of Blessing; see: Blessing, R. H. Acta Crystallogr., Sect. A 1995, 51, 33.

(22) SHELXTL: Structure Analysis Program, version 5.04; Siemens Industrial Automation Inc., Madison, WI, 1995

(23) R1 ) (∑||Fo| - |Fc||)/∑|Fo|. wR2 ) [∑[w(Fo2- Fc2)2]/∑[w(Fo2)2]]1/2, where w ) 1/[σ2_(F_o2_{) + (aP)}2_{+ bP] and P ) [(Max; 0, F}_o2_{) + 2F}_c2_]/3. GOF ) [∑[w(Fo2- Fc2)2]/(n - p)]1/2, where n and p denote the number of data and parameters, respectively.

Table 3. Crystal and Intensity Collection Data for [η5_:η1_-C

5H4C(CH3)dC(Ph)C(O)](PPh3)2Ru (3a) and

[(η5_-C

5H4C(CCPh)(OH)CH3)](Chiraphos)RuCl (6b)

3a 6b

mol formula C51H42OP2Ru C43H41ClOP2Ru

mol wt 833.86 772.22

space group Pnma P21

a, Å 18.5681(4) 9.3200(3) b, Å 15.2878(2) 19.1980(5) c, Å 14.1439(3) 11.2600(2) R (deg) 90 90 β (deg) 90 109.39(3) γ (deg) 90 90 V, Å3 _4014.96(13) _1900.39(9) Z 4 2 cryst dimens, mm3 _0.20_{× 0.10 × 0.10 0.35 × 0.30 × 0.25} Mo KR radiation: λ, Å 0.710 73 0.710 73

θ range for data

collection, deg 1.81-23.29 1.92-27.50 limiting indices (h, k, l) -20 to +18; -12 to +16; -15 to +8 -12 to +11; -24 to +23; -14 to +14 no. of rflns collected 11 876 53 516 no. of indep rflns 2969 7138 max and min

transmission

0.639 and 0.585 0.865 and 0.686 refinement method full-matrix least squares on F2

no. of data/restraints/ params 2730/0/263 7138/1/434 GOF 1.167 1.320 final R indices for I > 2σ(I) 0.0330/0.0702 0.0418/0.1035 for all data 0.0551/0.0798 0.0432/0.1082 ∆F (in final map), e/Å3 _{0.3570, -0.354} _{0.8350, -0.968}