Diphenyl(phenylethynyl)phosphine d6 [Rh(III), Ir(III), Ru(II)] complexes: Preparation of homo (μ-Cl)2 and hetero (μ-Cl)(μ-PPh2C≡CPh) bridged d6-d8 compounds

Article abstract of DOI:10.1021/om020052s

The novel P-coordinated diphenyl(phenylethynyl)phosphine complexes [Cp*MCl₂(PPh₂C≡CPh)] [M = Rh 1, Ir 2] have been prepared by the bridge splitting of [Cp*MCl₂]₂ with PPh₂C≡CPh. Treatment of 1 and 2 with AgTfO and PPh₂C≡CPh affords the corresponding cationic compounds [Cp*MCl(PPh₂C≡CPh)₂](OTf) [M = Rh 3, Ir 4, OTf = triflate], respectively. The analogous neutral Ru(II) derivative [Cp*RuCl(PPh₂C≡CPh)₂] 5 has been obtained by reaction of PPh₂C≡CPh and the binuclear complex [Cp*RuCl₂]₂ in the presence of Zn as the reductor. The molecular structures of 1 and 3-5 have been determined by single-crystal X-ray diffraction. The alkynyl fragments in cations 3 and 4 and in the neutral ruthenium derivative 5 are eclipsed, but the C_α?C_α interligand distances are longer than the minimal separation necessary (3.2-3.4 A?) to promote alkynyl coupling. The reactivity of these mono (1, 2) and bis[diphenyl(phenylethyny])phosphine] (3-5) complexes toward [cis-Pt(C₆F₅)₂(THF)₂] has been explored. Treatment of 1 with 1 equiv of [cis-Pt(C₆F₅)₂(THF)₂] in CH₂C1₂ affords the doubly chloride bridged [(PPh₂C=CPh)Cp*Rh(μ-Cl)₂Pt(C₆F₅ )₂] 6. In contrast, the analogous iridium derivative [Cp*IrCl₂(PPh₂C≡CPh)] 2 reacts with [cis-Pt(C₆F₅)₂(THF)₂], leading to a mixture of isomers [(PPh₂C≡CPh)Cp*Ir(μ-Cl)₂Pt(C₆F ₅)₂] 7a and [Cp*ClIr(μ-Cl)(_μ-k:η²PPh₂C ≡CPh)Pt(C₆F₅)₂] 7b (7a/7b ≈ 2.5:1). Similar cationic [(PPh₂C≡CPh)Cp*M(μ-Cl)(_μKP:η² -PPh₂C≡CPh)Pt(C₆F₅)₂](OT f) [M = Rh 8, Ir 9] and neutral [(PPh₂C≡CPh)Cp*Ru(μCl)(_μ-KP:η² -PPh₂C≡CPh)Pt(C₆F₅)₂] 10 hetero-bridged complexes are formed by treatment of the bis[diphenyl(phenylethynyl)]phosphine (3-5) complexes with [cis-Pt(C₆F₅)₂(THF)₂] in CH₂C1₂. The structure of 10 has been confirmed by a single-crystal X-ray diffraction analysis.

Full text of DOI:10.1021/om020052s

2314
Organometallics 2002, 21, 2314-2324
Dip h en yl(p h en yleth yn yl)p h osp h in e d 6 [Rh (III), Ir (III),
Ru (II)] Com p lexes: P r ep a r a tion of Hom o (µ-Cl)2 a n d
Heter o (µ-Cl)(µ-P P h 2CtCP h ) Br id ged d 6-d 8 Com p ou n d s
J esu´s R. Berenguer,† Mar´ıa Bernechea,† J uan Fornie´s,*,‡ J ulio Go´mez,† and
Elena Lalinde*,†
Departamento de Quı´mica-Grupo de Sı´ntesis Quı´mica de La Rioja, UA-CSIC, Universidad de
La Rioja, 26006, Logron˜o, Spain, and Departamento de Qu´ımica Inorga´nica, Instituto de
Ciencia de Materiales de Arago´n, Universidad de Zaragoza-Consejo Superior de
Investigaciones Cientı´ficas, 50009 Zaragoza, Spain
Received J anuary 24, 2002
The novel P-coordinated diphenyl(phenylethynyl)phosphine complexes [Cp*MCl2(PPh2Ct
CPh)] [M ) Rh 1, Ir 2] have been prepared by the bridge splitting of [Cp*MCl2]2 with PPh2Ct
CPh. Treatment of 1 and 2 with AgTfO and PPh2CtCPh affords the corresponding cationic
compounds [Cp*MCl(PPh2CtCPh)2](OTf) [M ) Rh 3, Ir 4, OTf ) triflate], respectively. The
analogous neutral Ru(II) derivative [Cp*RuCl(PPh2CtCPh)2] 5 has been obtained by reaction
of PPh2CtCPh and the binuclear complex [Cp*RuCl2]2 in the presence of Zn as the reductor.
The molecular structures of 1 and 3-5 have been determined by single-crystal X-ray
diffraction. The alkynyl fragments in cations 3 and 4 and in the neutral ruthenium derivative
5 are eclipsed, but the CR‚‚‚CR interligand distances are longer than the minimal separation
necessary (3.2-3.4 Å) to promote alkynyl coupling. The reactivity of these mono (1, 2) and
bis[diphenyl(phenylethynyl)phosphine] (3-5) complexes toward [cis-Pt(C6F5)2(THF)2] has
been explored. Treatment of 1 with 1 equiv of [cis-Pt(C6F5)2(THF)2] in CH2Cl2 affords the
doubly chloride bridged [(PPh2CtCPh)Cp*Rh(µ-Cl)2Pt(C6F5)2] 6. In contrast, the analogous
iridium derivative [Cp*IrCl2(PPh2CtCPh)] 2 reacts with [cis-Pt(C6F5)2(THF)2], leading to a
mixture of isomers [(PPh2CtCPh)Cp*Ir(µ-Cl)2Pt(C6F5)2] 7a and [Cp*ClIr(µ-Cl)(µ-κP:η2-
PPh2CtCPh)Pt(C6F5)2] 7b (7a /7b ≈ 2.5:1). Similar cationic [(PPh2CtCPh)Cp*M(µ-Cl)(µ-
κP:η2-PPh2CtCPh)Pt(C6F5)2](OTf) [M ) Rh 8, Ir 9] and neutral [(PPh2CtCPh)Cp*Ru(µ-
Cl)(µ-κP:η2-PPh2CtCPh)Pt(C6F5)2] 10 hetero-bridged complexes are formed by treatment of
the bis[diphenyl(phenylethynyl)]phosphine (3-5) complexes with [cis-Pt(C6F5)2(THF)2] in
CH2Cl2. The structure of 10 has been confirmed by a single-crystal X-ray diffraction analysis.
In tr od u ction
benzyne metal complexes is also a relatively easy
process.4c-n
There is a rich and extensive chemistry derived from
alkynylphosphines, PR′2CtCR, which are attractive due
to their versatile behavior in coordination chemistry and
reactivity. As polyfunctional ligands they have been
fairly well explored and a wide range of polynuclear
metal complexes have been prepared and studied.1 The
facility with which these ligands undergo a P-C(alkyne)
bond cleavage process, acting as sources of acetylide (Ct
CR) and phosphide (PR′2) fragments on transition metal
clusters, has also been well documented.2 In some cases
these fragments are further involved in coupling or
insertion reactions with other coordinated organic ligands
to give a range of new complexes in which phosphide
and/or the acetylide groups have coupled with the
organic species.3 The related coupling of an intact
PR′2CtCR is uncommon,4a,b but recent papers have
shown that the insertion of alkynyldiphenylphosphines
into reactive M-H or M-C of η2-benzyne or phospha-
Some previous experimental work5 and recent theo-
retical6 studies have demonstrated that simple P-
coordination of phosphinoalkynes polarizes the CtC
electron density, concentrating electron density on the
(1) (a) Went, M. J . Polyhedron 1995, 465 and references therein.
(b) Louattani E.; Suades, J . J . Organomet. Chem. 2000, 604, 234. (c)
J effery, J . C.; Pereira, R. M. S.; Vargas, M. D.; Went, M. J . J . Chem.
Soc., Dalton Trans. 1995, 1805. (d) Lang, H.; Weinmann, M.; Winter,
M.; Leise, M.; Imhof, W. J . Organomet. Chem. 1995, 503, 69. (e)
Louattani, E.; Suades, J .; Alvarez-Larena, A.; Piniella J . F.; Germain,
G. J . Organomet. Chem. 1996, 506, 121. (f) Dickson, R. S.; Desimone,
T.; Parker R. J .; Fallon, G. D. Organometallics 1997, 16, 1531. (g)
Imhof, W.; Eber, B.; Huttener G.; Emmeride, C. J . Organomet. Chem.
1993, 447, 21. (h) J ones, D. F.; Dixneuf, P. H.; Southern, T. G.;
Marouille, J .; Grandjean, D.; Guenot, P. Inorg. Chem. 1981, 20, 3247.
(i) J acobson, S.; Carty, A. J .; Mathew, M.; Palenik, G. J . J . Am. Chem.
Soc. 1974, 96, 4330. (j) Carty, A. J .; Paik, H. N.; Ng, T. W. J .
Organomet. Chem. 1974, 74, 279. (k) Patel, H. A.; Carty, A. J .; Hota,
N. K. J . Organomet. Chem. 1973, 50, 247. (l) Hota, N. K.; Patel, H. A.;
Carty, A. J .; Mathew, M.; Palenik, G. J . Organomet. Chem. 1971, 32,
C55. (m) Sappa, E.; Predieri, G.; Tiripicchio, A.; Tiripicchio-Camellini,
M. J . Organomet. Chem. 1985, 297, 103. (n) Carty, A. J .; Paik, H. N.;
Palenik, J . G. Inorg. Chem. 1977, 16, 300. (o) Carty, A. J .; Smith, W.
F.; Taylor, N. J . J . Organomet. Chem. 1978, 146, C1. (p) Carty, A. J .;
Dimock, K.; Paik, H. N.; Palenik, G. J . J . Organomet. Chem. 1974, 70,
C17. (q) Bruce, M. I.; Willians, M. L.; Skelton, B. W.; White, A. H. J .
Organomet. Chem. 1985, 282, C53.
* Corresponding authors. E-mail: elena.lalinde@dq.unirioja.es;
forniesj@posta.unizar.es.
† Universidad de La Rioja, UA-CSIC.
‡ Universidad de Zaragoza-CSIC.
10.1021/om020052s CCC: $22.00 © 2002 American Chemical Society
Publication on Web 05/03/2002

Preparation of d6-d8 Heterobinuclear Compounds
Organometallics, Vol. 21, No. 11, 2002 2315
carbon atom bonded to P. Although it is clear that this
fact activates the reactivity of the uncoordinated alkynyl
function, particularly toward nucleophilic attacks, and
could have important consequences in organic synthesis,
it is rather surprising that literature on simple mono-
nuclear complexes stabilized by P-coordinated alkynyl
ligands is scarce.1b,4b,6,7
As part of our interest in alkyne- and alkynide-
containing platinum complexes, we have explored the
η2-bonding capabilities of P-coordinated diphenylphos-
phinoalkyne complexes [cis-MX2(PPh2CtCR)2] with
respect to the effect of chelation on activation and/or
coupling reactions of both adjacent alkyne fragments.4a,b
We previously prepared the mononuclear platinum
complexes [cis-Pt(CtCR)2(PPh2CtCR′)2] (R, R′ ) Ph,
t-Bu)8 and examined their reactions with the solvento
complexes cis-[M(C6F5)2(THF)2] (M ) Pt, Pd; THF )
tetrahydrofuran). A number of homo- and heterobime-
tallic complexes stabilized with double alkynyl bridging
systems and unusual symmetrical [{(PPh2CtC-t-Bu)2-
Pt(µ3-η2-CtCPh)2}{M(C6F5)2}2] and [{Pt(µ-κP:η2-PPh2Ct
CPh)2(µ-η2-CtC-t-Bu)2}{Pt(C6F5)2}2] trimetallic species
were isolable by using 1:1 and 1:2 molar ratios, respec-
tively, indicating the following order of bonding capabil-
ity: CtCR > P-bonded PPh2CtCR and CtCPh units >
CtC-t-Bu fragments.8 The lower η2-bonding capability
of PPh2CtC-t-Bu has been attributed to the higher
steric demand of the bulky t-Bu group, and this is
consistent with the earlier observation that the reaction
of cis-[Pt(C6F5)2(THF)2] with [cis-PtCl2(PPh2CtC-t-Bu)2]
yielded binuclear double chloride bridged complexes
[(PPh2CtC-t-Bu)2Pt(µ-Cl)2Pt(C6F5)2], while the unusual
binuclear [(PPh2CtCPh)ClM(µ-Cl)(µ-κP:η2-PPh2CtCPh)-
Pt(C6F5)2] derivatives could be prepared using the di-
phenyl(phenylethynyl)phosphine species as precursors.9
More recently we observed that by forcing the η2-
complexation of both P-coordinated PPh2CtCPh mol-
ecules, on [cis-Pt(C6F5)2(PPh2CtCPh)2], the initial η2-
alkyne adduct [{(C6F5)2Pt(µ-κP:η2-PPh2CtCPh)2}{Pt-
(C6F5)2}] formed at low temperature evolves, through
an unexpectedly easy sequential insertion of both
PPh2CtCPh molecules, into a Pt-C6F5 bond, forming
unusual µ-2,3-bis(diphenylphosphino)-1,3-butadien-1-yl
binuclear complexes.10
Given the paucity of mononuclear complexes contain-
ing PPh2CtCR ligands and the interesting reaction
chemistry observed with P-bonded PPh2CtCPh and the
synthon “cis-Pt(C6F5)2”, we have extended our investiga-
tion to pentamethycyclopentadienyl d6 (Rh, Ir, and Ru)
complexes containing P-coordinated PPh2CtCPh ligands.
In this work we describe the synthesis and character-
ization of novel neutral [Cp*MCl2(PPh2CtCPh)] (M )
Rh, Ir), [Cp*RuCl2(PPh2CtCPh)], and cationic [Cp*MCl-
(PPh2CtCPh)2](OTf) (M ) Rh, Ir) complexes with
diphenyl(phenylethynyl)phosphine and examine their
reactivity toward [cis-Pt(C6F5)2(THF)2]. The preparation
of novel homo (µ-Cl)2 and unprecedented hetero (µ-Cl)-
(µ-κP:η2-PPh2CtCPh) bridged d6-d8 compounds is re-
ported.
(2) (a) Carty, A. J . Pure Appl. Chem. 1982, 54, 113 and references
therein. (b) Carty, A. J .; Taylor, N. J .; Smith, W. F. J . Chem. Soc.,
Chem. Commun. 1979, 750. (c) Nuccianore, D.; MacLaughlin, S. A.;
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A. A.; Randall, L. H.; MacLauglin, S. A.; Mott, G. N.; Taylor, N. J .;
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M. L.; Patrick, J . M.; White, A. H. J . Chem. Soc., Dalton Trans. 1985,
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221.
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Commun. 1991, 1511. (b) Sappa, E.; Pasquinelli, A.; Tiripicchio, A.;
Tiripicchio Camellini, M. J . Chem. Soc., Dalton Trans. 1989, 601. (c)
Davies, J . E.; Mays, M. J .; Raithby, P. R.; Sarveswaran, K.; Shields,
G. P. J . Organomet. Chem. 1999, 573, 180. (d) Davies, J . E.; Mays, M.
J .; Raitbhy, P. R.; Sarveswaran, K.; Solan, G. A. J . Chem. Soc., Dalton
Trans. 2001, 1269. (e) Delgado, E.; Chi, Y.; Wang, W.; Hogart, G.; Low,
P. J .; Enright, G. D.; Peng, S.-M.; Lee, G.-H.; Carty, A. J . Organome-
tallics 1998, 17, 2936. (f) Pereira, R. M. S.; Fujiwara, F. Y.; Vargas,
M. D.; Braga D.; Crepioni, F. Organometallics 1997, 16, 4833. (g)
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(4) (a) Carty, A. J .; Taylor, N. J .; J ohnson, D. K. J . Am. Chem. Soc.
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(c) Bennett, M. A.; Cobley, Ch. J .; Rae, A. D.; Wenger, E.; Willis, A. C.
Organometallics 2000, 19, 1522. (d) Edwards, A. J .; Macgregor, S. A.;
Rae, A. D.; Wenger, E.; Willis, A. C. Organometallics 2001, 20, 2864.
(e) Miquel, Y.; Cadierno, V.; Donnadieu, B.; Igau, A.; Mayoral, J . P.
Organometallics 2000, 19, 54. (f) Miquel, Y.; Igau, A.; Donnadieu, B.;
Mayoral, J . P.; Pirio, N.; Meunier, P. J . Am. Chem. Soc. 1998, 120,
3504. (g) Miquel, Y.; Igau, A.; Donnadieu, B.; Mayoral, J . P.; Dupuis,
L.; Pirio, N.; Meunier, P. Chem. Commun. 1997, 279. (h) Dupuis, L.;
Pirio, N.; Meunier, P.; Igau, A.; Donnadieu, D.; Mayoral, P. J . Angew.
Chem., Int. Ed. Engl. 1997, 36, 987. (i) Bennett, M. A.; Cobley, Ch. J .;
Wengers, E.; Willis, A. C. Chem. Commun. 1998, 1307. (j) Rosa, P.; Le
Floch, P.; Ricard, L.; Mathey, F. J . Am. Chem. Soc. 1997, 119, 9417.
(k) Dema, A. C.; Lukehart, Ch. M. Inorg. Chim. Acta 1997, 264, 193.
(l) Li, X.; Lukehart, Ch. M. Organometallics 1992, 11, 3993. (m) Montlo,
D.; Suades, J .; Dahan, F.; Mathieu, R. Organometallics 1990, 9, 2933.
See also: (n) Davies, J . E.; Mays, M. J .; Raithby, P. R.; Sarveswaran,
K.; Solan, G. A. J . Chem. Soc., Dalton Trans. 2000, 3331.
(5) (a) Liu, X.; Mok, K. F.; Leung, P.-H. Organometallics 2001, 20,
3918. (b) Dickson, R. S.; De Simone, T.; Parker, R. J .; Fallon, G. D.
Organometallics 1997, 16, 1531. (c) Simpson, R. T.; J acobson, S. E.;
Carty, A. J . J . Chem. Soc. Chem. Commun. 1973, 388. (d) Carty, A. J .;
J acobson, S. E.; Simpson, R. T. J . Am. Chem. Soc. 1975, 97, 7254. (e)
Carty, A. J .; J ohnson, D. K.; J acobson, S. E. J . Am. Chem. Soc. 1979,
101, 5612. (f) Taylor, N. J .; J acobson, S. E.; Carty, A. J . Inorg. Chem.
1975, 14, 2648. See also ref 7d.
Resu lts a n d Discu ssion
(i) Syn th esis of Mon on u clea r Com p lexes (1-5).
Treatment of the binuclear complexes [Cp*MCl(µ-Cl)]2
(M ) Rh, Ir) with 2 equiv of PPh2CtCPh in acetone at
room temperature affords the corresponding mono-
nuclear complexes [Cp*MCl2(PPh2CtCPh)] (M ) Rh 1,
Ir 2) (path i, Scheme 1), which are isolated as orange
(1) or yellow (2) solids in high yield (≈85%). As shown
in Scheme 1 (path ii) the cationic complexes [Cp*MCl-
(PPh2CtCPh)2](OTf) (M ) Rh 3, Ir 4, OTf ) triflate)
were prepared as yellow crystalline solids by removing
one of the chlorine ligands in 1 and 2 with silver triflate,
followed by subsequent treatment with additional diphen-
yl(phenylethynyl)phosphine. All attempts to coordinate
a third PPh2CtCPh ligand by removing both chlorine
(6) (a) Louattani, E.; Lledos, A.; Suades, J .; Alvarez-Larena, A.;
Piniella, F. Organometallics 1995, 14, 1053. See also: (b) Rossenberg,
D.; Drenth, W. Tetrahedron 1971, 27, 3893. (c) Albright, T. A.,
Freeman, W. J .; Schweizer, E. E. J . Am. Chem. Soc. 1975, 97, 2946.
(7) (a) Louattani, E.; Suades, J . Inorg. Chim. Acta 1999, 291, 207.
(b) Louattani, E.; Suades, J .; Mathieu, R. J . Organomet. Chem. 1991,
421, 395. (c) Hengefeld, A.; Nast, R. J . Organomet. Chem. 1983, 252,
375. (d) Hempsall, H. D.; Hyde, E. M.; Mentzer, E.; Saw, B. L. J . Chem.
Soc., Dalton Trans. 1997, 2285. (e) Wong, Y. S.; J acobson, S.; Chieh,
P. C.; Carty, A. J . Inorg. Chem. 1974, 13, 284. (f) Wheelock, K. S.;
Nelson, J . H.; J onassen, M. B. Inorg. Chim. Acta 1970, 4, 399. (g) King,
R. B.; Efraty, A. Inorg. Chim. Acta 1970, 4, 319. (h) Simpson, R. T.;
Carty, A. J . J . Coord. Chem. 1973, 2, 207. (i) Bardaji, M.; Laguna, A.;
J ones, P. G. Organometallics 2001, 20, 3906.
(9) Fornie´s, J .; Lalinde, E.; Mart´ın, A.; Moreno, M. T.; Welch, A. J .
J . Chem. Soc., Dalton Trans. 1995, 1333.
(10) (a) Chartmant, J . P. H.; Fornie´s; J .; Go´mez, J .; Lalinde, E.;
Moreno, M. T.; Orpen, A. G.; Solano, S. Angew. Chem., Int. Ed. Engl.
1999, 38, 3058. (b) Ara, I.; Fornie´s, J .; Garc´ıa, A.; Go´mez, J .; Lalinde,
E.; Moreno M. T. Chem. Eur. J ., in press.
(8) Ara, I.; Falvello, L. R.; Fernandez, S.; Fornie´s, J .; Lalinde, E.;
Mart´ın, A.; Moreno, M. T. Organometallics 1997, 16, 5923.

2316 Organometallics, Vol. 21, No. 11, 2002
Berenguer et al.
Sch em e 1
Ta ble 1. 13C Ch em ica l Sh ifts (δ, p p m ) of Acetylen ic Ca r bon s a n d Cou p lin g Con sta n ts (Hz) in CDCl3 of
Com p ou n d s 1-5 Com p a r ed w ith Th ose of th e F r ee P h osp h in e
δ(CR)
1J CR-P
δ(Câ)
2J Câ-P
δ(Câ) - δ(CR)
[RhIIICp*Cl2(PPh2CtCPh)] (1)
[IrIIICp*Cl2(PPh2CtCPh)] (2)
[RhIIICp*Cl(PPh2CtCPh)2](TfO) (3)
[IrIIICp*Cl(PPh2CtCPh)2](TfO) (4)
[RuIICp*Cl(PPh2CtCPh)2] (5)
PPh2CtCPh
81.3
80.1
77.9
77.8
85.8
86.5
90.5
104.2
101.6
116.8
77.5a
6.6
109.4
107.4
113.4
111.5
106.9
109.4
11.9
28.1
27.3
35.5
33.7
21.1
22.9
14.6
13.4b
16.1b
10.5b
a
b 2
1J C-P
+
3J C-P (AXX′ system).
J
+
4J C-P (AXX′ system).
C-P
groups in 1 or 2 in the presence of an excess of
phosphine were unsuccessful. This failure could be
presumably ascribed to steric hindrance about the
metals in the final complexes. Initially, the related
isoelectronic ruthenium neutral derivative [Cp*RuCl-
(PPh2CtCPh)2] 5 was obtained in very low yield (≈10%)
by the reaction of the Ru(III) [Cp*RuCl(µ-Cl)]2 complex
with only 2 equiv of PPh2CtCPh. Similar reductions
to bis(phosphine) derivatives [Cp*RuCl(PR3)2] have been
observed previously in the presence of small phosphines
such as PMe3.11 However, the yield can be increased to
ca. 40% by reduction of [Cp*RuCl(µ-Cl)]2 with Zn powder
in acetone, in the presence of 4 equiv of (diphenylphos-
phino)alkyne (Scheme 1, iii). The product is isolated, by
the usual workup, as an orange microcrystalline solid.
In this context, it should be noted that Nelson et al.
reported several years ago that the reaction of [CpRu-
(η1-PPh2CHdCH2)(η3-PPh2CHdCH2)](PF6) with RCt
CLi (R ) Ph, t-Bu) induces vinyl migration from
phosphorus to ruthenium yielding [CpRu(η1-PPh2CHd
CH2)(PPh2CtCR)(CHdCH2)] as the major product.12
All complexes are air-stable and have been character-
ized by the usual analytical and spectroscopic tech-
niques. In addition, the molecular structures of the
neutral derivatives 1 and 5, and those of the cationic
complexes 3 and 4, have been confirmed by single-
crystal X-ray diffraction. Moreover, conductivity mea-
surements in acetone solutions show that complexes 3
and 4 behave as 1:1 electrolytes.13 Evidence for the
P-coordination mode of the PPh2CtCPh ligand in all
complexes comes from the infrared spectra, which show
a strong (1-3) or medium (4, 5) ν(CtC) band in the
2169-2178 cm-1 region. Only small changes are ob-
served in the position of this band when going from the
neutral derivatives [Cp*MCl2(PPh2CtCPh)] (M ) Rh
1, Ir 2) to the cationic species [Cp*MCl(PPh2CtCPh)2]+
(M ) Rh 3, Ir 4), providing further support for a
previous suggestion1b,7a based on theoretical calcula-
tions,6 which relates the increase of the ν(CtC) of
phosphinoalkynes after P-coordination to a metal center
with the lesser delocalization of the phosphorus lone
pair on the π* CtC orbitals. Cationic complexes 3 and
4 also contain the characteristic stretching bands of the
-
CF3SO3 anion (see Experimental Section). Signifi-
cantly, the observed singlet (2, 4, 5) or doublet (1J P-Rh
147.8 Hz 1, 140.8 Hz 3) phosphorus resonances are, as
expected,6-9 downfield shifted with respect to that of the
free PPh2CtCPh (δ -33.55). The higher coordination
shifts appear in complexes containing second-row atoms,
and this is particularly observed in the ruthenium(II)
complex (∆(Hz) 53.65 5, 37.85 1, 35.85 3 vs 7.75 2, 1.25
4). Furthermore, the presence of the uncoordinated
alkyne fragments is clearly inferred from 13C NMR
spectroscopy, which exhibits the acetylenic carbon reso-
nances in the typical shift ranges. As can be observed
in Table 1, in all complexes the CR carbon resonances
are upfield shifted with regard to that of free PPh2Ct
(11) (a) Tilley, T. D.; Grubbs, R. H.; Bercaw, J . E. Organometallics
1984, 3, 274. (b) Arligui, T.; Border, C.; Chaudret, B.; Devillers, J .;
Poilblanc, R. Organometallics 1989, 8, 1308.
(12) J i, H.; Nelson, J . H.; Decian, A.; Fischer, J .; Solujic, L.;
Milosavljevic, E. B. Organometallics 1992, 11, 401.
(13) Geary, W. J . Coord. Chem. Rev. 1971, 7, 81.

Preparation of d6-d8 Heterobinuclear Compounds
Organometallics, Vol. 21, No. 11, 2002 2317
Ta ble 2. Cr ysta llogr a p h ic Da ta for 1‚2CHCl3, 3, 4, 5‚1.55CH2Cl2, a n d 10
1
3
4
5
10
empirical formula
fw
temp (K)
cryst syst
space group
a (Å)
C
32H32Cl8PRh
C54H51ClF3O4P2RhS
1053.31
293(2)
triclinic
P1h
11.0958(2)
15.4035(3)
16.0011(4)
96.5045(8)
98.9757(9)
109.2757(10)
2509.75(9)
2
C54H51ClF3IrO4P2S
1142.60
173(1)
triclinic
P1h
11.0540(2)
15.2321(2)
15.9130(4)
96.2500(6)
98.5577(7)
109.6825(11)
2458.09(8)
2
C51.55H48.10Cl4.10P2Ru
975.96
173(1)
orthorombic
Pnaa
14.7963(2)
24.1042(5)
26.3309(5)
90
C62H45ClF10P2PtRu
1373.53
120(1)
triclinic
P1h
11.1445(1)
12.7015(2)
19.8127(3)
101.7740(6)
104.3562(6)
96.6820(9)
2618.24(6)
2
834.06
293(2)
orthorhombic
P212121
9.7070(1)
14.9200(2)
24.9810(4)
90
b (Å)
c (Å)
R (deg)
â (deg)
90
90
90
90
γ (deg)
vol (Å3)
Z
3617.96(8)
4
1.531
1.129
1680
9391.0(3)
8
1.381
0.670
4009
Dcalcd (Mg/m3)
1.394
0.554
1084
1.544
2.935
1148
1.742
3.147
1352
abs coeff (mm-1
F(000)
)
θ range for data
collection (deg)
no. of data/
5.22-26.37
2.14-25.67
1.31-27.91
2.29-26.49
4.12-26.37
7124/6/413
9514/0/602
11692/0/602
9575/6/561
10633/0/699
restraints/params
GOF on F2
1.125
1.134
1.095
1.597
1.146
final R indices
[I > 2σ(I)]
R1 ) 0.0462,
wR2 ) 0.1090
R1 ) 0.0626,
wR2 ) 0.1155
0.542 and
R1 ) 0.0541,
wR2 ) 0.1247
R1 ) 0.0917,
wR2 ) 0.1396
0.491 and
R1 ) 0.0374,
wR2 ) 0.0797
R1 ) 0.0535,
wR2 ) 0.0849
1.002 and
R1 ) 0.0584,
wR2 ) 0.1609
R1 ) 0.0821,
wR2 ) 0.1694
0.954 and
R1 ) 0.0343,
wR2 ) 0.0607
R1 ) 0.0506,
wR2 ) 0.0640
0.864 and
R indices
(all data)
largest diff peak
and hole (e‚A-3
)
-0.628
-0.531
-1.563
-0.668
-0.619
Ta ble 3. Selected Bon d Len gth s (Å) a n d An gles
CPh (δ(CR) 86.5). This effect is particularly significant
in the cationic complexes 3 and 4. In contrast to this,
the acetylenic Câ carbon resonances clearly move down-
field in the cationic complexes 3 and 4 and slightly
upfield in the neutral ones (1, 2, 5). Consequently, the
chemical shift differences (δ(Câ-δCR)), which have been
previously related to the triple-bond polarization,2a,6 are
perceptibly higher in the cationic complexes 3 and 4
than in the neutral derivatives (1, 2). Interestingly, in
the ruthenium neutral compound 5 the acetylenic
carbon resonances lie very close to those of the free
ligand. According to the data in Table 1 it is apparent
that alkyne polarization is slightly enhanced in the
neutral M(III) (Rh, Ir) compounds (1, 2), and strongly
increased in the cationic M+(III) (Rh, Ir) species (3, 4).
However, complexation of two PPh2CtCPh molecules
to the “RuCp*Cl” fragment seems to have little influence
on alkyne polarization. In complexes containing two
PPh2CtCPh ligands (3, 4, and 5) the 13C signals due to
the phenyl rings bonded to phosphorus are observed to
be magnetically inequivalent, probably because of the
hindered rotation across the M-P bonds.
(d eg) for [Rh Cp *Cl2(P P h 2CtCP h )]
Rh(1)-C(Cp*) 2.149(5)-2.220(5) Rh(1)-C(2)
2.182(5)
Rh(1)-Cl(1)
Rh(1)-P(1)
C(11)-C(12)
2.4127(14)
2.3150(12)
1.209(7)
Rh(1)-Cl(2) 2.4017(14)
P(1)-C(11)
1.750(5)
P(1)-Rh(1)-Cl(1)
Cl(2)-Rh(1)-Cl(1)
91.34(5) P(1)-Rh(1)-Cl(2)
92.38(6) C(11)-P(1)-Rh(1)
89.75(5)
111.41(16)
C(11)-C(12)-C(13) 178.6(6)
C(12)-C(11)-P(1) 175.0(5)
displaying a virtually linear geometry and the C(11)-
C(12) bond distance being 1.209(7) Å, which is typical
of a CtC bond. The least sterically demanding alkynyl
fragment is oriented toward the bulky pentamethyl-
cyclopentadienyl ligand, a feature which has been also
found in [CpFe(CO)2PPh2CtCPh].6a The structures of
the cationic part of the bis(phosphine) compounds 3 and
4 and the molecular structure of the neutral ruthenium
complex are quite similar; ORTEP diagrams are shown
in Figure 2, and some characteristic bond lengths
and angles are provided in Table 4. The two cations in
3 (Rh) and 4 (Ir) and the neutral molecule in 5 (Ru)
The structures of 1 and 3-5 were determined by
single-crystal X-ray diffraction studies. Details of
the crystallographic determinations are indicated in
Table 2. An ORTEP view of the neutral monophosphine
complex is shown in Figure 1, and selected bond
distances and angles are given in Table 3. Complex 1
shows a pseudooctahedral geometry around the rhodium
atom, which is bonded to the pentamethylcyclopenta-
dienyl group (η5-), the two chlorine atoms, and the
phosphorus atom of the PPh2CtCPh ligand. The
two Rh-Cl (2.4017(14), 2.4127(14) Å) and the Rh-P
(2.3150(12) Å) bond lengths are comparable to those
found in other rhodium(III) complexes.14 The presence
of the uncoordinated alkynyl portion in the phosphine
ligand is confirmed by P(1), C(11), C(12), and C(13)
F igu r e 1. ORTEP view of [Cp*RhCl2(PPh2CtCPh)] 1.
Ellipsoids are drawn at the 50% probability level. Hydrogen
atoms have been omitted for clarity.
(14) Dromi, D.; Arena, C. G.; Nicolo, F.; Bruno, G.; Faraone, F. J .
Organomet. Chem. 1995, 485, 115 and references therein.

2318 Organometallics, Vol. 21, No. 11, 2002
Berenguer et al.
CHdCH2)2]+.14 Despite the different polarization of the
alkyne portions in these P-coordinated phosphinoalkyne
compounds, suggested by 13C NMR spectroscopy, the
chemically equivalent P-C(alkyne) bond distances in
both cations 3+ and 4+ and in the ruthenium complex 5
are identical within experimental error and comparable
to that seen in 1. The most striking feature of these
structures is the fact that both alkynyl entities are
essentially eclipsed (dihedral angle between both P-CR-
Câ-Cγ fragments: 0.1° 3+, 0.7° 4+, 0.9° 5) and located,
as in 1, close to the Cp* rings. However, the separation
between the alkyne termini (CR‚‚‚CR) is quite long: 3.8
and 3.76 Å in cations 3+ and 4+, respectively, and 3.776
Å in the neutral derivative (5). These values are long
compared to those previously found in square-planar cis-
bis[diphenyl(alkynyl)phosphine]platinum(II) complexes,
such as [cis-PtCl2(PPh2CtCPh)2] (3.110(10) Å)4b and
[cis-Pt(C6F5)2(PPh2CtCPh)2] (3.194 Å),10b in which in-
tramolecular coupling of the phosphinoalkyne ligands
was induced on heating.4b
(ii) Syn th esis of Heter obin u clea r P t(II)-M(d 6)
Com p lexes. As we noted in the Introduction, in the
course of our ongoing research on phosphinoalkynyl
platinum complexes we have recently observed an
unexpected easy sequential insertion of both PPh2CtCR
molecules (R ) Ph, Tol) into the very robust Pt-C6F5
bond simply by treating the cis-bis(phosphinoalkynyl)-
platinum or palladium(II) complexes [cis-M(C6F5)2-
(PPh2CtCR)2] with the solvento complex [cis-M(C6F5)2-
(THF)2] (THF ) tetrahydrofuran). As a continuation of
our work in this field we decided to examine the
reactivity of 1-5 toward [cis-Pt(C6F5)2(THF)2]. The
results of these reactions are summarized in Schemes
2 and 3. Reaction of the dichloro rhodium complex 1
with 1 equiv of [cis-Pt(C6F5)2(THF)2] yields the corre-
sponding dichloro-bridged heterobinuclear complex
[(PPh2CtCPh)Cp*Rh(µ-Cl)2Pt(C6F5)2] 6 in high yield
(76%). Elemental analysis and IR (ν(CtC) 2167 cm-1
;
ν(Rh-Cl)bridging 280, 267 cm-1) and NMR (1H, 13C, 19F,
and 31P) spectroscopic data are in accordance with a
symmetrical double chloride bridged compound with the
PPh2CtCPh molecule acting as a terminal P-coor-
dinated ligand. The particularly relevant features are
(a) the presence of a doublet phosphorus resonance
(1J Rh-P ) 149.0 Hz), which is found at a chemical shift
close to the value shown in the precursor (δ 7.2 in 6 vs
4.3 in 1), and (b) the existence, even at low temperature
(-80 °C in CD3COCD3), of only one set of C6F5 reso-
nances, confirming that both C6F5 ligands bound to
platinum are equivalent. It is worth noting that al-
though both acetylenic carbon resonances CR (δ 83.3)
and Câ (δ 116.7) are shifted to higher frequencies in
relation to the precursor (δ CR 81.3; Câ 109.4), the
resulting chemical shift difference δ(CR) - δ(Câ) in-
creases to 33.4 ppm, implying a higher alkyne polariza-
tion in the binuclear complex 6 than in 1. It should also
be mentioned that although complex 6 belongs to the
still uncommon family of d6-d8 heterobinuclear com-
pounds, several neutral [(PEt3)Cp*M(µ-Cl)2M′(C6F5)2]
(M ) Rh, Ir; M′ ) Pt, Pd)16a and even cationic
[(PMe3)Cp*M(µ-Cl)2PtL2](OTf)2 (M ) Rh, Ir; L2 ) dppe,
2PPh3)16b complexes have been previously reported. In
F igu r e 2. Molecular structure of (a) the cation [Cp*RhCl-
(PPh2CtCPh)2]+ in 3, (b) the cation [Cp*IrCl(PPh2Ct
CPh)2]+ in 4, and (c) [Cp*RuCl(PPh2CtCPh)2] 5. Ellipsoids
are drawn at the 50% probability level. Hydrogen atoms
have been omitted for clarity.
display the expected three-legged geometry about
the metal consistent with the spectral data. The M-Cl
and M-P distances and the P-M-P and P-M-Cl
angles are unexceptional for these types of metals and
ligands.15 In the cation 3+ the Rh-C(Cp*) (2.197(4)-
2.292(4) Å) and the Rh-P (2.3159(10), 2.3357(11) Å)
bond lengths are slightly longer than those observed in
1, but compare well with the values reported for other
related cationic complexes, such as [Cp*RhCl(PPh2-
(15) For Rh: (a) Eisen, M. S.; Haskel, A.; Chen, H.; Olmstead, M.
M.; Smith, D. P.; Maestre, M. F.; Fish, R. H. Organometallics 1995,
14, 2806. (b) Barthel-Rosa, L. P.; Catalano, V. J .; Maitra, K.; Nelson,
J . H. (c) Carmona, D.; Lahoz, F. J .; Oro, L.; Lamata, M. P.; Viguri, F.;
San J ose, E. Organometallics 1996, 15, 2961. For Ir: (d) Atherton, M.
J .; Faweett, J .; Holloway, J . H.; Hope, E. G.; Karacar, A.; Russell, D.;
Saunders, G. C. J . Chem. Soc., Dalton Trans. 1997, 1811. For Ru: (e)
de los Rios, I.; J imenez Tenorio, M. J .; Puerta, M. C.; Valerga, P.
Organometallics 1998, 17, 4392.
(16) (a) Ara, I.; Berenguer, J . R.; Eguiza´bal, E.; Fornie´s, J .; Lalinde,
E.; Mart´ın, A. Eur. J . Inorg. Chem. 2001, 1631. (b) Stang, P. J .; Huang,
Y.-H.; Arif, A. M. Organometallics 1992, 11, 23.

Preparation of d6-d8 Heterobinuclear Compounds
Organometallics, Vol. 21, No. 11, 2002 2319
Sch em e 2
Sch em e 3
Ta ble 4. Selected Bon d Len gth s (Å) a n d An gles (d eg) for [MCp *Cl(P P h 2CtCP h )2] (M ) Rh 3, Ir 4, Ru 5)
3
4
5
M-Cp*
M-Cl
M-P
Rh(1)-C
2.197(4)-2.262(4) Ir(1)-C
2.208(3)-2.284(4) Ru(1)-C
2.208(4)-2.259(4)
2.4649(9)
2.2811(11)
2.2810(10)
1.772(4)
1.757(4)
1.193(5)
1.212(5)
Rh(1)-Cl(1)
Rh(1)-P(1)
Rh(1)-P(2)
P(1)-C(11)
P(2)-C(31)
C(11)-C(12)
C(31)-C(32)
2.4048(11)
2.3159(10)
2.3357(11)
1.742(5)
Ir(1)-Cl(1)
2.4115(9)
2.2946(9)
2.3123(10)
1.753(4)
1.762(4)
1.199(5)
1.191(5)
Ru(1)-Cl(1)
Ir(1)-P(1)
Ru(1)-P(1)
Ru(1)-P(2)
P(1)-C(11)
P(2)-C(31)
C(11)-C(12)
C(31)-C(32)
Ir(1)-P(2)
P-CR
P(1)-C(11)
P(2)-C(31)
C(11)-C(12)
C(31)-C(32)
1.759(5)
CR-Câ
1.201(6)
1.191(6)
P-M-P
P(1)-Rh(1)-P(2)
P(1)-Rh(1)-Cl(1)
P(2)-Rh(1)-Cl(1)
C(11)-P(1)-Rh(1)
C(31)-P(2)-Rh(1)
C(12)-C(11)-P(1)
C(32)-C(31)-P(2)
94.59(4)
91.25(4)
93.62(4)
111.61(15)
110.32(15)
178.1(4)
177.9(5)
P(1)-Ir(1)-P(2)
P(1)-Ir(1)-Cl(1)
P(2)-Ir(1)-Cl(1)
C(11)-P(1)-Ir(1)
C(31)-P(2)-Ir(1)
C(12)-C(11)-P(1)
C(32)-C(31)-P(2)
94.51(3)
91.26(3)
93.98(3)
111.86(13)
110.26(13)
178.1(4)
177.2(4)
P(1)-Ru(1)-P(2)
P(1)-Ru(1)-Cl(1)
P(2)-Ru(1)-Cl(1)
C(11)-P(1)-Ru(1)
C(31)-P(2)-Ru(1)
C(12)-C(11)-P(1)
C(32)-C(31)-P(2)
93.28(4)
95.06(3)
93.03(3)
113.35(14)
112.79(15)
176.1(4)
175.5(5)
P-M-Cl
CR-P-M
Câ-CR-P
CR-Câ-Cγ C(11)-C(12)-C(13) 177.3(5)
C(11)-C(12)-C(13) 177.1(4)
C(31)-C(32)-C(33) 178.3(4)
C(11)-C(12)-C(13) 177.6(5)
C(31)-C(32)-C(33) 176.1(6)
C(31)-C(32)-C(33) 178.1(5)
contrast to complex 1, the iridium complex 2 reacts with
[cis-Pt(C6F5)2(THF)2] to yield a yellow solution, from
which a microcrystalline yellow solid of the expected
stoichiometry [(PPh2CtCPh)Cp*IrCl2Pt(C6F5)2] 7 can be
isolated in good yield. The spectroscopic analysis of this
solid reveals that it consists of a mixture of two isomers
7a and 7b in, approximately, 2.5:1 molar ratio. Their
formulations, deduced from IR and NMR (1H, 31P, and
19F) parameters, are those represented in Scheme 2. The
presence of terminal (ν(CtC) 2171 cm-1 7a ) and bridg-
ing (ν(CtC) 1960 cm-1 7b) PPh2CtCPh ligands in the
mixture is inferred not only from the IR data but also
from the 31P NMR spectroscopy. Thus, the minor isomer
(7b) shows a singlet resonance at δ 19.7, which is nearly
46 ppm shifted with respect to that of 2. This shift,
which is related to the loss of the electron ring current
associated with the π CtC bonds upon complexation,
has been previously observed in other complexes con-

2320 Organometallics, Vol. 21, No. 11, 2002
Berenguer et al.
F igu r e 3. Variable-temperature 19F NMR spectra of 7 (7a (+) + 7b (/)) in CD3COCD3.
taining µ-κP:η2-PPh2CtCPh bridging ligands.1b,8-10
A
yellow solids in moderate (42% 10) to good (75% 8, 67%
9) yields. The dimetallic formulation with a heteromixed
(µ-Cl)(µ-PPh2CtCPh) bridging system is consistent with
their analytical and spectroscopic data, and confirmed
by an X-ray diffraction study on the Ru-Pt complex 10
(see below). The mass spectra (ES+) of cationic com-
plexes exhibit the expected ion molecular fragment
[(PPh2CtCPh)Cp*M(µ-Cl)(µ-κP:η2-PPh2CtCPh)Pt-
(C6F5)2]+ (m/z 1375 72% 8, 1465 100% 9), and their
molar conductivities (148 Ω-1 cm2 mol-1 8, 144 Ω-1 cm2
mol-1 9) in acetone solution are in the expected range
for 1:1 electrolytes.13 Their IR spectra confirm the
presence of bridging (ν(CtC) 1980 cm-1 8, 1981 cm-1
9, 1990 cm-1 10) and terminal (ν(CtC) 2172 cm-1 8,
2178 cm-1 9, 2169 cm-1 10) PPh2CtCPh ligands, and
additional information is inferred from the 31P and 19F
NMR spectra (their solubility is low for 13C NMR
studies). Thus, two different phosphorus resonances (AX
systems in 9 and 10, and AMX (X ) Rh) in 8) are
observed in the 31P NMR spectra of these complexes,
confirming the inequivalence of both phosphines. The
low-field resonance (δ 36.7 8, 10.5 9, 59.9 10), which is
strongly deshielded in relation to the corresponding
precursor, is attributed to the bridging κP:η2-PPh2Ct
CPh, and the high field signal (δ 2.1 8, -31.7 9, 19.2
10), which appears close to those seen in the precursor,
can be assigned to the terminal P-coordinated ligand.
The 2J P-P coupling constants (51.5 Hz 8, 26.1 Hz 9, 41.6
Hz 10) are typical for this type of complexes. The 19F
NMR spectra display two different sets of resonances,
which are consistent with two chemically inequivalent
C6F5 groups, one trans to Cl and the other one trans to
the η2 acetylenic entity. Furthermore, the presence of
different ligands trans to the C6F5 rings induces differ-
ent rotation energy barriers for the C6F5 groups. As a
result of this situation, while the rigid pattern for one
of the rings does not change over all the range of
temperatures investigated, the set of signals for the
other ring displays a marked dependence upon temper-
ature. The variable-temperature spectra of 8 are shown
in Figure 4. As can be seen, by increasing temperature,
whereas the two o-F (-115.8 and -124.5 ppm) and two
m-F (-163.5 and -164.1 ppm) signals corresponding to
one of the C6F5 groups broaden, the resonances of the
second set (δ o-F -116.6, -121.8; 2-m-F -162.7) only
give rise to sharper signals. The two o-F resonances
coalesce at ca. 313 K, and from this equilibration the
free energy of activation ∆Gq at the coalescence tem-
singlet at δ -12.4 was attributed to the major isomer
(7a ) stabilized by chloride bridges and containing P-
bonded PPh2CtCPh. The position of both signals is not
temperature dependent, but the 7a /7b molar ratio
decreases by cooling, being ≈3.8:1 at 323 K and only
2:1 at 193 K. This variation,which is also found in the
1H and 19F NMR spectra, suggests that the mixture is
an equilibrium of both isomers. However, the presence
of separated patterns, even at high temperature, indi-
cates that the exchange between both isomers is very
slow on the NMR time scale. This behavior is clearly
revealed by 19F NMR spectroscopy, which shows the two
expected sets of signals, each one showing its typical
temperature-dependent pattern (see Figure 3). As can
be observed in Figure 3, the limiting low-temperature
spectrum is compatible with a static structure for both
isomers. 7a exhibits a set of five distinct signals
confirming that both C6F5 groups are rigid on the NMR
time scale and equivalent. By raising the temperature
the two o-F doublets and the two m-F multiplets
coalesce (above 233 K o-F) to only one o-F doublet and
one m-F multiplet resonance, most likely due to a fast
rotation around its Pt-C bonds. The approximate
calculated activation energy (∆Gq
≈ 45.9 kJ /mol) is
233
slightly lower than that observed in the Rh-Pt deriva-
tive 6 (∆Gq
≈ 55.3 kJ /mol). The minor isomer 7b
258
shows two sets of static C6F5 resonances, confirming the
inequivalence of the two C6F5 ligands bound to platinum
(trans to µ-Cl and trans to µ-PPh2CtCPh). The variable-
temperature pattern observed for 7b closely resembles
that of derivatives 8-10 (see below). At low temperature
the restricted rotation of the Pt-C bonds renders the
two halves of each C6F5 group inequivalent. Upon
warming, the four o-F and the four m-F signals broaden
and coalesce (≈ between 273 and 283 K o-F, and 263-
273 K m-F), while the two p-F signals remain un-
changed. At the highest experimental temperature (323
K), however, neither of the two averaged o-F signals
(one for each C6F5) merges from the base line.
The preparation of a series of hetero-bridged (µ-Cl)-
(µ-PPh2CtCPh) complexes was achieved by treat-
ment of the starting bis[diphenyl(phenylethynyl)-
phosphine] 3-5 with [cis-Pt(C6F5)2(THF)2] (Scheme 3).
The final cationic [(PPh2CtCPh)Cp*M(µ-Cl)(µ-κP:η2-
PPh2CtCPh)Pt(C6F5)2](OTf) (M ) Rh 8, Ir 9) and
neutral [(PPh2CtCPh)Cp*Ru(µ-Cl)(µ-κP:η2-PPh2CtCPh)-
Pt(C6F5)2] 10 hetero-bridged complexes are isolated as

Preparation of d6-d8 Heterobinuclear Compounds
Organometallics, Vol. 21, No. 11, 2002 2321
F igu r e 4. Variable-temperature 19F NMR spectra of [(PPh2CtCPh)Cp*Rh(µ-Cl)(µ-κP:η2-PPh2CtCPh)Pt(C6F5)2](OTf) 8
in CDCl3.
Ta ble 5. Selected Bon d Len gth s (Å) a n d An gles
(d eg) for [(P P h 2CtCP h )Cp *Ru (µ-Cl)(µ-KP :η2-
P P h 2CtCP h )P t(C6F 5)2] 10
Pt(1)-C(1)
Pt(1)-C(51)
Pt(1)-Cl(1)
Ru(1)-P(1)
Ru(1)-Cl(1)
C(1)-C(2)
2.229(3)
2.026(4)
2.3785(9)
Pt(1)-C(2)
2.226(4)
2.027(4)
Pt(1)-C(57)
Ru(1)-C(Cp*) 2.219(4)-2.258(3)
2.2912(10) Ru(1)-P(2)
2.3124(9)
1.802(4)
1.459(5)
1.197(5)
4.126
2.4358(10) P(1)-C(1)
1.224(5)
1.773(4)
C(2)-C(3)
C(21)-C(22)
Ru(1)-Pt(1)
P(2)-C(21)
C(22)-C(23) 1.443(5)
C(51)-Pt(1)-C(57)
C(57)-Pt(1)-C(1)
C(51)-Pt(1)-Cl(1)
C(1)-Pt(1)-Cl(1)
P(1)-Ru(1)-Cl(1)
Pt(1)-Cl(1)-Ru(1) 117.95(4) C(2)-C(1)-P(1)
C(1)-C(2)-C(3) 166.3(4)
C(21)-C(22)-C(23) 179.5(4)
85.62(14) C(57)-Pt(1)-C(2)
104.83(14) C(2)-Pt(1)-C(1)
85.66(14)
31.90(12)
86.86(10) C(2)-Pt(1)-Cl(1) 100.98(10)
82.96(10) P(1)-Ru(1)-P(2)
87.60(3) P(2)-Ru(1)-Cl(1)
92.55(3)
91.87(3)
162.3(3)
F igu r e 5. View of the molecular structure of complex
[(P P h 2CtCP h )Cp*Ru (µ-Cl)(µ-κP :η2-P P h 2CtCP h )P t -
(C6F5)2] 10. Ellipsoids are drawn at the 50% probability
level. Hydrogen atoms have been omitted for clarity.
C(22)-C(21)-P(2) 175.3(3)
noalkynyl ligand in the precursor. The ruthenium atom
is pseudotetrahedral surrounded by one pentamethyl-
cyclopentadienyl ligand, two phosphorus atoms of the
two PPh2CtCPh ligands, and the chlorine bridging
atom. The platinum center of the “Pt(C6F5)2” unit
completes its usual square-planar geometry with the
alkyne entity of one P(1)Ph2CtCPh ligand (C(1)tC(2)),
which is bonded in a µ-κP:η2 bridging fashion. The Ru-
C(Cp*) bond distances are similar to those seen in the
precursor 5, suggesting that the formation of the dimer
has no influence on these distances. As expected, the
two Ru-P distances are different, but curiously the Ru-
P(1)(bridging) (2.2912(10) Å) distance is slightly shorter
than the Ru-P(2)(terminal) (2.3124(9) Å) bond length,
and both of them are slightly greater than those of 5.
Compared with the precursor, the Ru-Cl bridging
distance is somewhat reduced (2.4358(10) Å in 10 vs
2.4649(9) Å in 5). As we have previously found in related
[(PEt3)Cp*M(µ-X)2Pt(C6F5)2] (M ) Rh, Ir; X ) Cl,
CtCR)16a,19 complexes, the “Pt(C6F5)2” unit is directed
toward the same side as the Cp* ring, the Pt-Cl
(2.3785(9) Å) and Pt-C(1,2)(acetylenic) (2.229(3), 2.226(4)
Å) bond distances being comparable to those found
in [(PPh2CtCPh)ClPt(µ-Cl)(µ-PPh2CtCPh)Pt(C6F5)2]
(Pt(1)-Cl(1) 2.380(4) Å; Pt(1)-C(13,14) 2.150(12),
2.200(12) Å).9 The coordination of the C(1)-C(2) acetyl-
perature for the rotation process has been calculated
to be 54.25 kJ /mol. The m-F resonances coalesce to a
multiplet above 283 K. Essentially similar patterns are
observed for the Ir-Pt 9 and the Ru-Pt 10 compounds,
for which the calculated activation energies for the
restricted carbon-platinum bond rotation are ∆Gq
≈
313
54.29 kJ /mol 9 and ∆G*303 ≈ 52.4 kJ /mol 10, respec-
tively.
The structure proposed for these 7-10 binuclear
complexes was confirmed by X-ray crystallography using
a single crystal of 10, obtained from slow diffusion of
hexane into a solution of 10 in CH2Cl2 at -20 °C (Figure
5 and Tables 2 and 5). This complex is a new member
of the very small family of heterometallic Ru(II)-Pt(II)
complexes, which have been previously reported.14,18
The structure clearly shows that the bis[diphenyl-
(phenylethynyl)phosphine] precursor complex 5 acts as
a mixed Cl,η2-(alkyne) bidentate ligand toward the “cis-
Pt(C6F5)2” fragment and reveals that the formation of
10 requires a significant reorientation of one phosphi-
(17) Verkade, J . G., Quin L. D., Eds. 31P-NMR Spectroscopy in
Stereochemical Analysis (Methods in Stereochemical Analysis, 8);
VCH: New York, 1987; p 91.
(18) (a) Younus, M.; Long, N. J .; Raithby, P. R.; Lewis, J . J .
Organomet. Chem. 1998, 570, 55. (b) Harriman, A.; Hissler, M.; Ziessel,
R.; De Cian, A.; Fischer, J . J . Chem. Soc., Dalton Trans. 1995, 4067.
(c) Hissler, M.; Ziessel, R. J . Chem. Soc., Dalton Trans. 1995, 893. (d)
Sato, M.; Mugi, E. J . Organomet. Chem. 1996, 508, 159. (e) A search
in the CSD (version 5.22) gives only 12 examples of Ru(II)-Pt(II) X-ray
characterized binuclear complexes.
(19) Ara, I.; Berenguer, J . R.; Eguiza´bal, E.; Fornie´s, J .; Lalinde,
E.; Mart´ın, A.; Mart´ınez, F. Organometallics 1998, 17, 4578.

2322 Organometallics, Vol. 21, No. 11, 2002
Berenguer et al.
and all coupling constants are given in hertz. IR spectra were
obtained on a Perkin-Elmer FT-IR Spectrum 1000 spectrom-
eter using Nujol mulls between polyethylene sheets. Elemental
analyses were carried out with a Perkin-Elmer 2400 CHNS/O
microanalyzer. Mass spectra were recorded on an HP-5989B
mass spectrometer using the ES(+) or ES(-) techniques.
Conductivities were measured in acetone solutions (ca. 5 ×
10-4 mol‚L-1) using a Crison GLP31 conductimeter. [cis-Pt-
(C6F5)2(THF)2],20 [Cp*MCl(µ-Cl)]2 (M ) Rh, Ir),21 [Cp*RuCl(µ-
Cl)]2,11a and PPh2CtCPh22 were prepared by published meth-
ods.
enic fragment to Pt(1) causes the expected distortion
from linearity effect (angles at C1 and C2 being 162.3°
and 166.3°, respectively), but the C1C2 triple bond
distance (1.224(5) Å) is similar to the uncoordinated
C21C22 length (1.197(5) Å). The internal angles associ-
ated with the metal centers and the bridging chlorine
atom (Cl(1)-Ru(1)-P(1) 87.60(3)°; Cl(1)-Pt(1)-C(1)
82.96(10)° acute and Ru(1)-Cl(1)-Pt(1) 117.95(4)° ob-
tuse) are in accordance with the very long Ru‚‚‚Pt
distance (4.126 Å) found, which excludes any bonding
metal interaction.
Syn th esis of [(η5-Cp *)Rh Cl2(P P h 2CtCP h )] (1). PPh2Ct
CPh (0.46 g, 1.62 mmol) was added to a suspension of
[Cp*RhCl(µ-Cl)]2 (0.50 g, 0.81 mmol) in 30 mL of acetone, and
the mixture was stirred for 5 min. The resulting red solution
was evaporated to dryness and the residue treated with diethyl
ether to yield 1 as an orange solid. Yield: 0.83 g (86%). Anal.
Calcd for C30Cl2H30PRh: C, 60.52; H, 5.08. Found: C, 60.94;
H, 4.74. MS ES(+): m/z 559 [M - Cl]+ 100%; molecular peak
not observed. IR (cm-1): ν(CtC) 2171(s); ν(Rh-Cl) 279(m),
Con clu sion s
In summary, we have described the preparation and
structures of several neutral [Cp*MCl2(PPh2CtCPh)]
(M ) Rh 1, Ir 2), [Cp*RuCl(PPh2CtCPh)2] 5, and
cationic [Cp*MCl(PPh2CtCPh)2](OTf) (M ) Rh 3, Ir 4)
diphenyl(phenylethynyl)phosphine complexes. 13C NMR
studies suggest that the alkyne polarization upon
alkyne complexation of PPh2CtCPh molecules strongly
depends on the metal and the charge of the complex.
Thus, while complexation of two PPh2CtCPh ligands
to the neutral and low-valence “Cp*RuCl” fragment
seems to have no influence on the alkyne polarization,
a notable polarization is observed for the analogous
substituted high-valence cationic units “[Cp*MCl]+” [M
) Rh, Ir(III)]. For the monophosphine neutral deriva-
tives 1 and 2 alkyne polarization is less than in the
cationic complexes 3 and 4, but it is clearly enhanced
with respect to that of free PPh2CtCPh. The interaction
of these mononuclear complexes 1-5 with the labile
solvento complex [cis-Pt(C6F5)2(THF)2] has been also
studied. Several hetero-bridged (µ-Cl)(µ-κP:η2-PPh2Ct
CPh) heterobinuclear complexes 8-10 have been pre-
pared by using the chloro-bis(phosphine) complexes as
starting materials. Interestingly, while the dichloro-
bridged Rh(II)-Pt(II) complex [(PPh2CtCPh)Cp*Rh(µ-
Cl)2Pt(C6F5)2] 6 was obtained starting from 1, a final
mixture of (µ-Cl)2 7a and (µ-Cl)(µ-κP:η2-PPh2CtCPh) 7b
was obtained by using the iridium species [Cp*IrCl2-
(PPh2CtCPh)] 2 as the precursor, suggesting that the
η2 bonding capability of the PPh2CtCPh ligand is also
susceptible to the nature of the metal center to which
this ligand is P-bonded. The six d6-d8 species undergo
fluxional behavior observable by 19F NMR spectroscopy,
which is presumably related to the rotation around the
Pt-ipso-C(pentafluorophenyl) bond. In the hetero-
bridged complexes 8-10, one of the C6F5 rings behaves
as rigid and the dynamic behavior observed for the other
ring is ascribed to the less sterically hindered C6F5 ring
mutually cis to the µ-Cl bridging group. Furthermore,
the rotation of this ring could be more easily achieved
due to the fact that it is located trans to the η2 acetylenic
entity, which is known to have a higher trans influence
than the chlorine atom.
1
270(sh). H NMR (CDCl3, δ): 8.14 (m, 4H), 7.64 (m, 2H), 7.44
4
(m, 3H), 7.37 (m, 6H) (Ph, PPh2CtCPh); 1.52 (d, J P-H ) 4.0,
2
15H, Cp*). 13C NMR (CDCl3, δ): 133.9 (d, J C-P ) 11.0, o-C,
PPh2); 132.3 (d, 4J C-P ) 1.5, o-C, tCPh); 131.1 (d, 2J C-P ) 53.8,
4
ipso-C, PPh2); 130.8 (d, J C-P ) 2.8, p-C, PPh2); 130.6 (s, p-C,
tCPh); 129.0 (s, m-C, tCPh); 128.1 (d,3J C-P ) 11.2, m-C,
3
2
PPh2); 121.1 (d, J C-P ) 3.2, ipso-C, tCPh); 109.4 (d, J C-P
)
1
2
11.9, Câ); 99.4 (dd, J C-Rh ) 6.9, J C-P ) 3.1, C5(CH3)5); 81.3
(d, J C-P ) 90.5, CR); 8.8 (d, J C-Rh ) 1.4, C5(CH3)5). 31P NMR
1
2
1
(CDCl3, δ): 4.3 (d, J P-Rh ) 147.8).
Syn th esis of [(η5-Cp *)Ir Cl2(P P h 2CtCP h )] (2). A suspen-
sion of [Ir(η5-Cp*)Cl2]2 (0.2 g, 0.25 mmol) in acetone (20 mL)
was treated with PPh2CtCPh (0.14 g, 0.50 mmol). After 5 min
of stirring the resulting yellow solution was evaporated to
dryness and the residue treated with diethyl ether to give 2
as a yellow solid. Yield: 0.29 g (85%). Anal. Calcd for C30Cl2H30
-
IrP: C, 52.63; H, 4.42. Found: C, 52.73; H, 4.44. MS ES(+):
m/z 786 [M + CtCPh]+ 11%; 649 [M - Cl]+ 100%; molecular
peak not observed. IR (cm-1): ν(CtC) 2175(s); ν(Ir-Cl) 300(m),
1
271(m). H NMR (CDCl3, δ): 8.09 (m, 4H), 7.62 (m, 2H), 7.43
4
(m, 3H), 7.36 (m, 6H) (Ph, PPh2CtCPh); 1.54 (d, J P-H ) 2.6,
2
15H, Cp*). 13C NMR (CDCl3, δ): 133.4 (d, J C-P ) 11.0, o-C,
PPh2); 131.9 (d, 4J C-P ) 1.6, o-C, tCPh); 130.9 (d, 2J C-P ) 63.0,
4
ipso-C, PPh2); 130.3 (d, J C-P ) 2.7, p-C, PPh2); 130.1 (s, p-C,
tCPh); 128.5 (s, m-C, tCPh); 127.5 (d, 3J C-P ) 5.9, m-C, PPh2),
3
2
120.5 (d, J C-P ) 3.2, ipso-C, tCPh); 107.4 (d, J C-P ) 14.6,
Câ); 92.4 (d, 2J C-P ) 2.9, C5(CH3)5); 80.1 (d, 1J C-P ) 104.2, CR);
7.8 (d, J C-P ) 0.8, C5(CH3)5). 31P NMR (CDCl3, δ): -25.8 (s).
3
Syn th esis of [(η5-Cp *)Rh Cl(P P h 2CtCP h )2](OTf) (3). A
light-protected solution of [(η5-Cp*)RhCl2(PPh2CtCPh)] 1 (0.06
g, 0.10 mmol) in acetone (20 mL) was treated with Ag(CF3-
SO3) (0.026 g, 0.10 mmol) and the resulting mixture stirred
at room temperature for 2 h. The solid AgCl formed was
filtered through Celite and the filtrate treated with 0.03 g of
PPh2CtCPh (0.10 mmol). After 5 min of stirring the solvent
was removed in vacuo and the residue treated with diethyl
ether. The resulting yellow solid was collected by filtration and
then recrystallized from acetone/hexane. Yield: 0.06 g (63%).
Anal. Calcd for C51ClF3H45O3P2RhS: C, 61.55; H, 4.56; S, 3.22.
Found: C, 61.30; H, 4.76; S, 3.03. ΛM: 144 Ω-1‚cm2‚mol-1. MS
ES(+): m/z 846 [M]+ 4%; 559 [M - PPh2CtCPh]+ 100%. IR
(cm-1): ν(CtC) 2173(s); ν(CF3SO3-) 1275(s), 1224(w), 1149(m),
1032(m). 1H NMR (CDCl3, δ): 8.01 (m, 4H), 7.53 (m, 10H),
7.36 (m, 10H), 7.05 (t, J H-H ) 7.4, 2H), 6.91 (t, J H-H ) 7.4,
Exp er im en ta l Section
4
4H) (Ph, PPh2CtCPh); 1.43 (t, J P-H ) 4.0, 15H, Cp*). 13C
All manipulations were carried out under an argon atmo-
sphere, and solvents (hexane, alkane mixture) were dried by
standard procedures and distilled under dry N2 before use.
NMR spectra were recorded on a Bruker ARX-300 spectrom-
eter, and the temperature of the routine NMR measurements
was 293 K. Chemical shifts are reported in parts per million
relative to external standards (SiMe4, CFCl3, and 85% H3PO4),
(20) Uso´n, R.; Fornie´s, J .; Toma´s, M.; Menjo´n, B. Organometallics
1985, 4, 1912.
(21) Kang, J . W.; Moseley, K.; Maitlis, P. J . J . Am. Chem. Soc. 1969,
91, 5970.
(22) Carty, A. J .; Hota, N. K.; Ng, T. W.; Pate, H. A.; O’Connor, T.
J . Can. J . Chem. 1971, 49, 2706.

Preparation of d6-d8 Heterobinuclear Compounds
Organometallics, Vol. 21, No. 11, 2002 2323
2
NMR (CDCl3, δ): 132.7 (“t”, J C-P + 4J C-P ) 11.6, o-C, PPh2);
[RhCp*Cl(PPh2CtCPh)]+ 100%; molecular peak not observed.
IR (cm-1): ν(CtC) 2167(s); ν(C6F5)X-sens 813(s), 800(s); ν(Rh-
Cl)bridging 280(w), 267(w). 1H NMR (CD3COCD3, δ): 8.20 (m,
4H), 7.90 (d, J H-H ) 8.0, 2H), 7.66 (m, 7H), 7.55 (m, 2H) (Ph,
PPh2CtCPh); 1.69 (d, 4J P-H ) 4.0, 15H, Cp*). 13C NMR (CD3-
132.3 (o-C, PPh2 and tCPh); 131.9 (s, p-C, PPh2); 131.6 (d,
1J C-P ) 56.0, ipso-C, PPh2); 131.6 (s, p-C, tCPh); 131.1 (s, p-C,
PPh2); 129.4 (s, m-C, tCPh); 128.93 (“t”, 3J C-P + 5J C-P ) 11.9,
m-C, PPh2); 128.89 (“t”, 3J C-P + 5J C-P ) 11.5, m-C, PPh2); 119.7
2
2
(s, ipso-C, tCPh); 113.4 (t, J C-P
+
4J C-P ) 13.4, Câ); 107.1
COCD3, δ): 155.0-135.0 (C6F5); 138.0 (d, J C-P ) 11.6, o-C,
(dt, 1J C-Rh ) 5.2, 2J C-P ) 2.3, C5(CH3)5); 77.9 (d, 1J C-P ) 101.6,
PPh2); 137.3 (d, J C-P ) 1.6, o-C, CtCPh); 136.6 (d, J C-P )
2
4
4
CR); 9.1 (s, C5(CH3)5). 19F NMR (CDCl3, δ): -78.56 (s, CF3). 31
P
2.9, p-C, PPh2); 136.0 (s, p-C, tCPh), 135.8 (d, J C-P ) 57.6,
1
3
NMR (CDCl3, δ): 2.3 (d, J P-Rh ) 140.8).
ipso-C, PPh2); 134.0 (s, m-C, tCPh); 133.8 (d, J C-P ) 11.7,
m-C, PPh2); 124.9 (d, 3J C-P ) 3.2, ipso-C, tCPh); 116.7 (d, 2J C-P
Syn th esis of [(η5-Cp *)Ir Cl(P P h 2CtCP h )2](OTf) (4). A
solution of 2 (0.06 g, 0.09 mmol) in 20 mL of acetone was
treated with Ag(CF3SO3) (0.02 g, 0.09 mmol) and stirred in
the absence of light for 3 h at room temperature. Filtration of
the mixture through Celite and addition of PPh2CtCPh (0.025
g, 0.088 mmol) gave a yellow solution, which was stirred for
30 min and then concentrated to ca. 5 mL in vacuo. The
solution was treated with diethyl ether (20 mL) and stored
for 2 h at -40 °C to give 4 as a yellow microcrystalline solid,
which was separated by filtration and washed with diethyl
ether. Yield: 0.05 g (48%). Anal. Calcd for C51ClF3H45O3P2-
IrS: C, 56.48; H, 4.18; S, 2.96. Found: C, 56.55; H, 4.45; S,
2.21. ΛM: 150 Ω-1‚cm2‚mol-1. MS ES(+): m/z 935 [M]+ 100%;
649 [M - PPh2CtCPh]+ 24%; 599 [M - PPh2CtCPh - Cl -
CH3]+ 45%. IR (cm-1): ν(CtC) 2169(m); ν(CF3SO3-) 1274(s),
1224(w), 1148(m), 1032(m). 1H NMR (CDCl3, δ): 7.91 (m, 4H),
1
2
) 13.3, Câ); 107.3 (dd, J C-Rh ) 7.3, J C-P ) 2.6, C5(CH3)5);
83.3 (d, J C-P ) 95.8, CR); 13.1 (d, J C-Rh ) 1.2, C5(CH3)5). 19F
1
2
3
NMR (CD3COCD3, δ): at 20 °C, -118.00 (d, J Pt-o-F ) 530,
4-o-F); -165.30 (t, 2-p-F); -167.10 (m, 4-m-F). At -80 °C,
-117.86, -117.91 (overlapping of two doublets, 3J Pt-o-F ≈ 490,
4-o-F); -163.60 (t, 2-p-F); -165.77 (m, 4-m-F). 31P NMR (CD3-
1
COCD3, δ): 7.2 (d, J P-Rh ) 149.0). Prolonged accumulation
causes partial decomposition: some of the signals are at-
tributed to the salt [Cp*Rh(µ-Cl)3RhCp*]2[Pt(C6F5)2(µ-Cl)2](δH
1.76 (s). δF -117.5, o-F; -166.7, p-F; -167.7, m-F), and a
platinum phosphine species is also detected (δP -2.9, J Pt-P
2850).
)
Rea ction of [(η5-Cp *)Ir Cl2(P P h 2CtCP h )] (2) w ith [cis-
P t(C6F 5)2(THF )2]: Syn th esis of [(P P h 2CtCP h )(η5-Cp *)-
Ir (µ-Cl)2P t (C6F 5)2] (7a ) a n d [Cp *ClIr (µ-Cl)(µ-P P h 2Ct
CP h )P t(C6F 5)2] (7b). Starting from 2 (0.10 g, 0.15 mmol) and
[cis-Pt(C6F5)2(THF)2] (0,01 g, 0.15 mmol), and following a
procedure similar to that described for the synthesis of 6, a
yellow solid was obtained. This was identified by NMR
spectroscopy as a mixture of 7a and 7b (2.5:1). All attempts
to separate these products by repeated crystallizations were
4
7.46 (m, 20H), 7.00 (m, 6H) (Ph, PPh2CtCPh); 1.44 (t, J P-H
) 2.4, 15H, Cp*). 13C NMR (CDCl3, δ): 32.7 (“t”, 2J C-P + 4J C-P
) 11.9, o-C, PPh2); 132.2 (o-C, PPh2 and tCPh); 131.8 (s, p-C,
1
PPh2); 131.2 (s, p-C, tCPh); 131.1 (d, J C-P ) 68.0, ipso-C,
1
PPh2); 131.0 (s, p-C, PPh2); 130.0 (d, J C-P ) 64.0, ipso-C,
PPh2); 129.1 (s, m-C, tCPh); 128.7 (“t”, J C-P + 5J C-P ) 12.5,
3
m-C, PPh2); 128.5 (“t”, 3J C-P + 5J C-P ) 12.2, m-C, PPh2); 119.6
(s, ipso-C, tCPh); 111.5 (t, 2J C-P + 4J C-P ) 16.1, Câ); 101.7 (s,
unsuccessful. Yield: 0.12 g (69%). Anal. Calcd for C42Cl2F10H30-
IrPPt: C, 41.56; H, 2.49. Found: C, 41.59, H, 2.66. MS
ES(+): m/z 649 [IrCp*Cl(PPh2CtCPh)]+ 100%; molecular peak
not observed. MS ES(-): m/z 1093 [Pt2(C6F5)4Cl]- 25%; 565
[Pt(C6F5)2Cl]- 100%; 529 [Pt(C6F5)2]- 15%; molecular peak not
observed. IR (cm-1): ν(CtC) 2171(vs) (7a ), 1960(vs) (7b);
ν(C6F5)X-sens 810(s), 800(s); ν(Ir-Cl) 312(w) (7b); 290(w), 268(w)
C5(CH3)5); 77.8 (d, J C-P ) 116.8, CR); 8.2 (s, C5(CH3)5). 19F
1
NMR (CDCl3, δ): -78.55 (s, CF3). 31P NMR (CDCl3, δ): -32.3
(s).
Syn th esis of [(η5-Cp *)Ru Cl(P P h 2CtCP h )2] (5). PPh2Ct
CPh (0.19 g, 0.65 mmol) and Zn powder (0.5 g, 7.6 mmol) were
added to a solution of [Cp*RuCl(µ-Cl)]2 (0.10 g, 0.16 mmol) in
acetone (20 mL). The mixture was stirred for 1.5 h and then
filtered through Celite. The resultant orange filtrate was
concentrated to a small volume (2-3 mL) to give orange
crystals of 5, which were filtered and washed with cold acetone.
Yield: 0.11 g (39%). (Analytical data of a microcrystalline
1
(7a , 7b). H NMR (CD3COCD3, δ) 7a : 8.10 (m), 7.90 (d, J )
6.8), 7.65 (m), 7.56 (m) (Ph, PPh2CtCPh); 1.69 (d, 4J P-H ) 2.4,
Cp*). 7b: 8.20-7.65 (overlapped with those of 7a ), 7.40, 7.26
(m, Ph, PPh2CtCPh); 1.52 (d, 4J P-H ) 2.2, Cp*). 19F NMR (CD3-
3
COCD3, δ) at 20 °C, 7a : -118.10 (d, J Pt-o-F ) 524, o-F);
-164.90 (t, p-F), -166.90 (m, m-F). 7b: The o-F signals
coalesce at this temperature; -161.75 (t, p-F); -163.07 (t, p-F);
-164.92 (overlapped with p-F of 7a , m-F); -166.83 (m, m-F).
At -80 °C, 7a : -117.94 (d, o-F); -118.31 (d, o-F); -163.11 (t,
p-F); -165.48 (t, m-F); -165.56 (t, m-F). 7b: -116.50 (d, o-F);
-117.35 (d, o-F); -119.18 (d, o-F); -120.78 (d, o-F); -159.86
(t, p-F); -161.49 (t, p-F); -163.11 (overlapped with p-F of 7a ,
m-F); -163.72 (m, m-F), -163.94 (m, m-F), -164.46 (t, m-F).
31P NMR (CD3COCD3, δ): -12.4(s) (7a ); 19.7(s) (7b). The solid
is not soluble enough for 13C NMR study.
sample crystallized from CHCl3/hexane.) Anal. Calcd for C50
-
ClH45P2Ru‚CHCl3: C, 63.89; H, 4.31. Found: C, 64.19; H, 4.00.
MS ES(+): m/z 809 [M - Cl]+ 3%; 769 [M - Ph]+ 75%; 558
[M - PPh2CtCPh]+ 32%; 523 [M - PPh2CtCPh - Cl]+ 100%;
molecular peak not observed. IR (cm-1): ν(CtC) 2178(m);
1
ν(Ru-Cl) 294(w). H NMR (CDCl3, δ): 8.07 (m, 4H), 7.58 (m,
4H), 7.48 (m, 4H), 7.34 (m, 2H), 7.28 (m, 4H), 7.23 (m, 6H),
6.81 (m, 6H) (Ph, PPh2CtCPh); 1.33 (s, 15H, Cp*). 13C NMR
(CDCl3, δ): 139.3 (“t”, 1J C-P + 3J C-P ) 48.1, ipso-C, PPh2); 137.4
1
2
(“t”, J C-P
+
3J C-P ) 42.3, ipso-C, PPh2); 132.8 (“t”, J C-P
+
Syn th esis of [(P P h 2CtCP h )(η5-Cp *)M(µ-Cl)(µ-P P h 2Ct
CP h )P t(C6F 5)2](CF 3SO3) (M ) Rh 8, M ) Ir 9). A general
procedure is as follows: [cis-Pt(C6F5)2(THF)2] (0.03 g, 0.045
mmol) is added to a solution of [(η5-Cp*)MCl(PPh2CtCPh)2](CF3-
SO3) (M ) Rh 3, 0.045 g, 0.045 mmol; M ) Ir 4, 0.05 g, 0.045
mmol) in 20 mL of CH2Cl2, and the mixture is stirred for 10
min. Evaporation of the mixture to dryness and treatment of
the residue with cold Et2O affords complexes 8 and 9 as orange
and yellow solids, respectively.
4J C-P ) 12.2, o-C, PPh2); 132.0 (“t”, J C-P + 4J C-P ) 11.0, o-C,
PPh2); 131.8 (s, o-C, tCPh); 129.1 (s, p-C, tCPh); 129.0 (s,
p-C, PPh2); 128.5 (s, m-C, tCPh); 128.2 (s, p-C, PPh2); 127.6
2
(“t”, 3J C-P + 5J C-P ) 10.0, m-C, PPh2); 127.5 (“t”, 3J C-P + 5J C-P
2
) 9.6, m-C, PPh2); 122.8 (s, ipso-C, tCPh); 106.9 (“t”, J C-P
+
4J C-P ) 10.5, Câ); 90.8 (t, J C-P ) 4.2, C5(CH3)5); 85.8 (AXX′
2
1
3
five-line pattern, J C-P + J C-P ) 77.5, CR); 8.8 (s, C5(CH3)5).
31P NMR (CDCl3, δ): 20.1 (s).
Syn th esis of [(P P h 2CtCP h )Cp *Rh (η-Cl)2P t(C6F 5)2] (6).
[cis-Pt(C6F5)2(THF)2] (0.12 g, 0.17 mmol) was added to a
solution of [(η5-Cp*)RhCl2(PPh2CtCPh)] 1 (0.10 g, 0.17 mmol)
in CH2Cl2 (20 mL) and the mixture stirred for 20 min. The
solvent was evaporated in vacuo, and the resulting orange
residue was treated with diethyl ether, filtered, and washed
Da ta for 8. Yield: 0.05 g (75%). Anal. Calcd for C63-
ClF13H45O3P2PtRhS: C, 49.64; H, 2.98; S, 2.10. Found: C,
50.08, H, 3.17, S, 1.89. ΛM: 148 Ω-1‚cm2‚mol-1. MS ES(+): m/z
1375 [M]+ 72%; 1089 [M - PPh2CtCPh] 100%. IR (cm-1):
-
ν(CtC)terminal 2172(s); ν(CtC)bridging 1980(m), ν(CF3SO3
)
1266(m), 1224(w), 1154(m), 1032(m); ν(C6F5)X-sens 808(m),
1
with diethyl ether. Yield: 0.15 g (76%). Anal. Calcd for C42
-
799(m). H NMR (CDCl3, δ): 7.88 (m, 2H), 7.74 (m, 3H), 7.53
Cl2F10H30PPtRh: C, 44.86; H, 2.69. Found: C, 44.60, H, 2.64.
MS ES(+): m/z 1156 [Rh2Cp*2Cl3(PPh2CtCPh)2] 11%, 559
(m, 15H), 7.35 (m, 4H), 7.17 (m, 3H), 6.70 (m, 1H), 6.60 (m,
1H), 6.36 (m, 1H) (Ph, PPh2CtCPh); 1.39 (t, 4J P-H ) 3.82, 15H,

2324 Organometallics, Vol. 21, No. 11, 2002
Berenguer et al.
Cp*). 19F NMR (CDCl3, δ) at 20 °C: -78.54 (s, 3F, CF3);
-116.40 (br, 3J Pt-o-F ) 377, 1-o-F); -117.34 (d, 3J Pt-o-F ) 379,
1-o-F); -121.33 (d, 3J Pt-o-F ) 395, 1-o-F); -123.70 (sbr, 3J Pt-o-F
) 301, 1-o-F); -158.70 (t, 1-p-F); -161.00 (t, 1-p-F); -163.33
(m, 2-m-F); -164.36 (m, 2-m-F). At -50 °C: -78.82 (s, 3F, CF3),
(t, 1-p-F); -164.04 (m, 1-m-F); -164.50 (m, 1-m-F); -164.80
(m, 1-m-F); -165.50 (m, 1-m-F). 31P NMR (CDCl3, δ): 59.9 (d,
2J P-P ) 41.6); 19.2 (d, 2J P-P ) 41.6). The complex is not soluble
enough for 13C NMR study.
X-r a y Cr ysta llogr a p h y. Crystals of complexes 1, 3, 4, 5,
and 10 were obtained by slow diffusion of hexane into a
chloroform (1), acetone (3 and 4), or dichloromethane (5 and
10) solution of each compound. Table 2 reports details of the
structural analyses for all complexes. For all the complexes,
X-ray intensity data were collected with a NONIUS kCCD
area-detector diffractometer, using graphite-monochromated
Mo KR radiation. Images were processed using the DENZO
and SCALEPACK suite of programs,23 doing the absorption
correction at this point, except for 1, for which absorption
correction was done using SORTAV.24 The structures were
solved by Patterson and Fourier methods using the DIRDIF92
program25 and refined by full-matrix least squares on F2 using
the SHELXL-97 program.26 All non-hydrogen atoms were
assigned anisotropic displacement parameters, and all hydro-
gen atoms were constrained to idealized geometries fixing
isotropic displacement parameters of 1.2 for the phenyl and
1.5 for the methyl groups times the Uiso value of their attached
carbon. For 1, the absolute structure parameter is 0.04(4). The
crystals obtained for complexes 3, 4, and 10 did not contain
lattice solvent; it was, however, found in 1 (two molecules of
CHCl3 with one of them disorded in two different positions)
and 5 (1.55 CH2Cl2). A residual peak (1.002 e/A3) close to the
Ir atom was observed for 4, but with no chemical meaning.
3
3
-115.8 (d, J Pt-o-F ) 416, 1-o-F); -116.6 (d, J Pt-o-F ) 357,
3
3
1-o-F); -121.8 (d, J Pt-o-F ) 401, 1-o-F); -124.5 (d, J Pt-o-F
)
297, 1-o-F); -158.2 (t, 1-p-F); -160.3 (t, 1-p-F); -162.7 (m, 2-m-
F); -163.5 (m, 1-m-F), -164.1 (m, 1-m-F). 31P NMR (CDCl3,
2
1
2
δ): 36.7 (dd, J P-P ) 51.5, J P-Rh ) 138.8); 2.1 (dd, J P-P
)
51.5, J P-Rh ) 143). The complex is not soluble enough for 13C
1
NMR study.
Da ta for 9. Yield: 0.05 g (67%). Anal. Calcd for C63ClF13H45
-
IrO3P2PtS: C, 46.89; H, 2.81; S, 2.00 Found: C, 46.82; H, 3.06;
S, 1.67. ΛM: 144 Ω-1‚cm2‚mol-1. MS ES(+): m/z 1465 [M]+
100%; 1178 [M - PPh2CtCPh] 10%, 935 [M - Pt(C6F5)2]+ 49%.
IR (cm-1): ν(CtC)terminal 2178(s); ν(CtC)bridging 1981(m);
ν(CF3SO3-) 1264(s), 1224(w), 1154(s), 1032(s); ν(C6F5)X-sens
807(m), 799(m); ν(M-Cl) 279(w). 1H NMR (CDCl3, δ): 7.81 (m,
5H), 7.50 (m, 17H), 7.34 (m, 1H), 7.17 (m, 2H), 6.67 (m, 4H),
6.35 (m, 1H) (Ph, PPh2CtCPh); 1.43 (s, 15H, Cp*). 19F NMR
3
(CDCl3, δ) at 20 °C: -78.51 (s, 3F, CF3); -116.44 (d, J Pt-o-F
3
≈ 360, 1-o-F); -117.50 (d, J Pt-o-F ) 380, 1-o-F); -121.40 (d,
3
3J Pt-o-F ) 400, 1-o-F); -123.95 (s br, J Pt-o-F ≈ 330, 1-o-F);
-158.36 (t, 1-p-F); -160.80 (t, 1-p-F); -163.10 (m, 2-m-F);
-164.25 (s br, 2-m-F). At -50 °C: -78.77 (s, 3F, CF3); -115.92
3
3
(d, J Pt-o-F ) 365, 1-o-F); -116.80 (d, J Pt-o-F ) 365, 1-o-F);
3
3
-121.80 (d, J Pt-o-F ) 382, 1-o-F); -124.50 (d, J Pt-o-F ) 299,
1-o-F); -157.89 (t, 1-p-F); -160.10 (t, 1-p-F); -162.50 (t, 2-m-
F); -163.30 (m, 1-m-F); -164.00 (m, 1-m-F). 31P NMR (CDCl3,
δ): 10.5 (d, 2J P-P ) 26.1); -31.7 (d, 2J P-P ) 26.1). The complex
is not soluble enough for 13C NMR.
Ack n ow led gm en t. We wish to thank the Direccio´n
General de Investigacio´n Cient´ıfica y Te´cnica, Spain
(Projects PB98-1595-C02-01, 02), and the Comunidad
de La Rioja (APCI-200015 and a grant to M. Bernechea)
for their support of this research.
Syn th esis of [(P P h 2CtCP h )(η5-Cp*)Ru (µ-Cl)(µ-P P h 2Ct
CP h )P t(C6F 5)] 10. This complex was prepared, as a yellow
solid, in the way described for 8 and 9, starting from [(η5-Cp*)-
RuCl(PPh2CtCPh)2] 5 (0.05 g, 0.06 mmol) and [cis-Pt(C6F5)2-
(THF)2] (0.04 g, 0.06 mmol). Yield: 0.035 g (42%). Anal. Calcd
for C62ClF10H45P2PtRu: C, 54.21; H, 3.30. Found: C, 54.65;
H, 3.05. MS ES(+): m/z 844 [M - Pt(C6F5)2]+ 6%; 753 [M -
(C6F5)2 - (PPh2CtCPh)]+ 22%; 721 [M - (C6F5)2 - (PPh2Ct
CPh) - Cl + 3H]+ 100%; 523 [RuCp*(PPh2CtCPh)]+ 6%;
molecular peak not observed. IR (cm-1): ν(CtC)terminal 2169(s);
ν(CtC)bridging 1990(s); ν(C6F5)X-sens 807(m); 796(m). 1H NMR
(CDCl3, δ): 7.86 (m, 5H), 7.55 (m, 3H), 7.47 (m, 6H), 7.40 (m,
1H), 7.35 (m, 7H), 7.19 (d, 1H), 7.05 (t, 2H), 6.64 (t, 2H), 6.35
(m, 2H), 6.1 (t, 1H) (Ph, PPh2CtCPh); 1.25 (s, 15H, Cp*). 19F
NMR (CDCl3, δ) at 20 °C: ≈ -116.0 (s br, 1-o-F); -116.51 (d,
Su p p or tin g In for m a tion Ava ila ble: Further details of
the structure determination of 1‚2CHCl3, 3, 4, 5‚1.55CH2Cl2,
and 10, including atomic coordinates, bond distances and
angles, and thermal parameters. Crystallographic data in CIF
format. This material is available free of charge via the
Internet at http://pubs.acs.org.
OM020052S
(23) Otwinowski, Z.; Minor, W. In Methods in Enzymology; Carter,
C. W., J r., Sweet, R. M., Eds.; Academic Press: New York, 1997; Vol.
276A, p 307.
3
3J Pt-o-F ) 394, 1-o-F); -121.02 (d, J Pt-o-F ) 416, 1-o-F); ≈
(24) Blessing, R. H. Acta Crystallogr. 1995, A51, 33.
-123.5 (s br, 1-o-F); -161.80 (t, 1-p-F); -163.40 (t, 1-p-F);
-164.74 (m, 1-m-F); -165.44 (m, 1-m-F); -165.76 (m, 2-m-F).
(25) Beurskens, P. T.; Beurskens, G.; Bosman, W. P.; de Gelder, R.;
Garc´ıa-Granda, S.; Gould, R. O.; Smith, J . M. M.; Smykalla, C. The
DIRDIF92 program system; Technical Report of the Crystallography
Laboratory; University of Nijmegen: The Netherlands, 1992.
(26) Sheldrick, G. M. SHELX-97, a program for the refinement of
crystal structures; University of Go¨ttingen: Go¨ttingen, Germany, 1997.
3
At -50 °C: -115.70 (d, J Pt-o-F ) 357, 1-o-F); -116.20 (d,
3
3J Pt-o-F ) 386, 1-o-F); -121.50 (d, J Pt-o-F ) 386, 1-o-F);
-124.50 (d, 3J Pt-o-F ) 268, 1-o-F); -161.20 (t, 1-p-F); -162.60