One-pot synthesis of (η6-arene)bis(triphenylphosphine)(methyl)ruthenium(II) cations. X-ray structures of [(η6-C6H6)Ru(Me)(PPh3)2 ]-[AlCl2Me2] and the η5-thiophene analogue

Article abstract of DOI:10.1021/om0200860

A one-pot synthesis for a series of [(η⁶-arene)Ru(Me)(PPh₃)₂]⁺ complexes was reported. X-ray structures of the η⁶-C₆H₆ and η⁵-thiophene derivatives were presented. The complexes were synthesized by the reaction of RuCl₂(PPh₃)₃ with an excess of AlMe₃ in the presence of a solvent or an admixture with hexane. The complexes were formed in a multistep mechanism involving replacement of chloride ligands by methyl and by displacement of PPh₃ from Ru by an arene or thiophene molecule.

Full text of DOI:10.1021/om0200860

2336
Organometallics 2002, 21, 2336-2339
On e-P ot Syn th esis of
(η6-Ar en e)bis(tr ip h en ylp h osp h in e)(m eth yl)r u th en iu m (II)
Ca tion s. X-r a y Str u ctu r es of [(η6-C6H6)Ru (Me)(P P h 3)2]-
[AlCl2Me2] a n d th e η5-Th iop h en e An a logu e
Xinggao Fang, J ohn G. Watkin, Brian L. Scott, Kevin D. J ohn, and
Gregory J . Kubas*
Chemistry Division, MS J 514, Los Alamos National Laboratory,
Los Alamos, New Mexico 87545
Received February 4, 2002
Summary: We report one-pot syntheses for a series of
complexes of the type [(η6-arene)RuIIMe(PPh3)2][AlCl2-
Me2] in high yields and X-ray structures of the η6-C6H6
and η5-thiophene derivatives. Other derivatives include
fluorobenzene and mesitylene complexes, and all of the
complexes are synthesized by addition of AlMe3 to RuCl2-
(PPh3)3 in the neat arene solvent or in an admixture with
hexane for thiophene and fluorobenzene.
For example heterobidentate P,O-donor ligands produce
chiral metal centers when bound to arene-Ru complexes,
and [(cymene)Ru(η2-chelate-P,O)Cl]+ cations are precur-
sors to 16-electron dicationic strong Lewis acids that
have potential use in asymmetric catalysis.3e
The [(arene)Ru(Me)(PPh3)2]+ complexes we report
here should be useful precursors for complexes of the
above type and other arene-Ru species, e.g., by substitu-
tion of PPh3 by chiral ligands. Yet, there is not a general
synthesis reported for complexes of this type. A multi-
step synthesis of cation 1 with a PF6- counteranion was
reported previously.4 We now have found a much easier
one-pot synthesis for this arene methyl ruthenium(II)
cation as well as heretofore unreported analogues with
mesitylene (2), thiophene (3), and fluorobenzene (4)
ligands. X-ray structures of complexes 1 and 3 show η6-
coordination of benzene and η5-coordination of thiophene.
Complexes 1-4 are synthesized by reaction of com-
mercially available RuCl2(PPh3)3 with a 2- to 4-fold
excess of AlMe3 in the presence of benzene, mesitylene,
thiophene, and fluorobenzene, respectively (Scheme 1).
In the case of 3 and 4, hexane solvent is used to reduce
the amount of arene reagents, and the reaction mixtures
are stirred for 2-3 days because of the poor solubility
of RuCl2(PPh3)3 in this solvent. These complexes are
presumably formed in a multistep mechanism involving
replacement of chloride ligands by methyl and by
displacement of PPh3 from Ru by an arene or thiophene
molecule L (eq 1).
During our ongoing research on electrophilic cationic
transition metal complexes, e.g., [Mn(CO)3(P)2(CH2-
Cl2)]+ and [RuCl(PP)2]+ (P and PP ) tied-back phosphite
and diphosphonite),1 we desired to prepare RuCl(Me)-
(PPh3)3. The intention was to remove the methyl group
by well-established procedures1 to possibly form 16e
cationic solvento species such as [RuCl(PPh3)3(CH2Cl2)]+
that could be useful precursors for small molecule
binding or catalysts. The sought-after RuCl(Me)(PPh3)3
complex had been reported to be synthesized by a
reaction of RuCl2(PPh3)3 with AlMe3 in benzene, but no
NMR data were given.2 By following the reported
procedure, we isolated instead the complex [(η6-C6H6)-
Ru(Me)(PPh3)2][AlCl2Me2] (1) in high yield. η6-Arene-
(alkyl)ruthenium(II) cations are related to various
ruthenium-catalyzed organic transformations, most no-
tably asymmetric synthesis, and therefore are of high
significance.3 There is renewed interest in (arene)-
ruthenium(II) complexes owing to the great stability of
the metal-arene bond in these compounds compared
to Cp analogues and their ability to act as effective
precursors for catalytic asymmetric hydrogenation and
to promote the synthesis of complex organic compounds.
RuCl2(PPh3)3 + AlMe3 9
L8
(1) (a) Fang, X.-G.; Vincent, J . H.; Scott, B. L.; Kubas, G. J . J .
Organomet. Chem. 2000, 609, 95. (b) Fang, X.-G.; Scott, B. L.; J ohn,
K. D.; Kubas, G. J . Organometallics 2000, 19, 4141. (c) Fang, X.; Scott,
B. L.; Watkin, J . G.; Kubas, G. J . Organometallics 2001, 20, 2413. (d)
Huhmann-Vincent, J .; Scott, B. L.; Kubas, G. J . J . Am. Chem. Soc.
1998, 120, 6808. (e) Huhmann-Vincent, J .; Scott, B. L.; Kubas, G. J .
Inorg. Chem. 1999, 38, 115. (f) Huhmann-Vincent, J .; Scott, B. L.;
Kubas, G. J . Inorg. Chim. Acta 1999, 294, 240.
(2) Porter, R. A.; Shriver, D. F. J . Organomet. Chem. 1975, 90, 41.
(3) For selected recent examples, see: (a) Ceccanti, A.; Diversi, P.;
Ingrosso, G.; Laschi, F.; Lucherini, A.; Magagna, S.; Zanello, P. J .
Organomet. Chem. 1996, 526, 251. (b) LeGendre, P.; Offenbecher, M.;
Bruneau, C.; Dixneuf, P. H. Tetrahedron: Asymmetry 1998, 9, 2279.
(c) Faller, J . W.; Patel, B. P.; Albrizzio, M. A.; Curtis, M. Organome-
tallics 1999, 18, 3096. (d) Furstner, A.; Liebl, M.; Lehmann, C. W.;
Picquet, M.; Kunz, R.; Bruneau, C.; Touchard, D.; Dixneuf, P. H. Chem.
Eur. J . 2000, 6, 1847. (e) Faller, J . W.; Liu, X.; Parr, J . Chirality 2000,
12, 325. (f) Arena, C. G.; Calamia, S.; Faraone, F.; Graiff, C.; Tiripicchio,
A. Dalton 2000, 3149. For a review, see: Lebozec, H.; Touchard, D.;
Dixneuf, P. H. Adv. Organomet. Chem. 1989, 29, 163.
[LRu(Me)(PPh3)2][AlCl2Me2] + PPh3 (1)
The elimination of PPh3 is perhaps aided by association
of AlMe3 or a similarly Lewis-acidic derivative such as
AlClMe2 to the phosphine. The arene and thiophene
complexes are isolated as yellow solids in good yields
(e.g., 85% for 1). NMR spectroscopy and crystallography
show primarily the presence of AlCl2Me2- counteranions
and not mixed anions such AlClMe3 in the isolated
products. However satisfactory elemental analyses were
difficult to obtain in some cases, particularly for 4,
-
(4) Werner, R.; Werner, H. Chem. Ber. 1982, 115, 3781.
10.1021/om0200860 CCC: $22.00 © 2002 American Chemical Society
Publication on Web 04/24/2002

Notes
Organometallics, Vol. 21, No. 11, 2002 2337
Sch em e 1
F igu r e 1. Thermal ellipsoid plot (50% probability el-
lipsoids) of [(η6-C6H6)Ru(Me)(PPh3)2][AlMe2Cl2]‚CH2Cl2,
1‚CH2Cl2.
indicating the anion composition could be mixed to a
minor degree or the anion is sensitive to degradation
-
by trace air or moisture. The AlCl2Me2 anion has
previously been reported to form in a reaction of a 4-fold
excess of AlMe3 with YbCl3 in toluene in a sealed tube
(12 h, 80 °C) to form [YbCl2(15-crown-5)][AlCl2Me2] in
the presence of 15-crown-5.5 The anion was stated to
impart air-sensitivity to the complex, and its composi-
tion was revealed in the X-ray structure of the Yb
complex. The authors surmised that anions ranging
from AlMe4 to AlCl4 were probably present in solution
and that [AlCl2Me2]- formed the least soluble species
when paired with the cation. The aluminate anion in 1
can readily be replaced by borate-type anions as dis-
cussed below. As shown in Scheme 1, the synthesis of
the arene cations works for both electron-rich (mesityl-
ene) and electron-poor (C6H5F) arenes as well as aro-
matic heterocycles (thiophene). However, when for
example hexane or C6F6 is used as the sole solvent, a
clean product could not be isolated in our hands.
F igu r e 2. Thermal ellipsoid plot (50% probability el-
lipsoids) of [(η5-thiophene)Ru(Me)(PPh3)2][AlMe2Cl2]‚CH2-
Cl2, 3‚CH2Cl2.
form Ph3CMe and AlCl2Me rather than removing Me
from the metal, which would have been desirable to form
highly electrophilic dications such as [(η6-C6H6)Ru-
(PPh3)2(S)]2+ (S ) solvent). Indeed, no reactions of [(η6-
C6H6)Ru(Me)(PPh3)2][BArF] with either [Ph3C][BArF] or
[H(OEt2)2][BArF] were found to occur. Treatment with
HOSO2CF3 apparently does remove the methyl group
as methane, but a clean product was not obtained.
The η6-coordination of arene and η5-coordination of
The 1H NMR spectra of 1-4 in CDCl3 all show a
sharp singlet for the methyl groups in the AlCl2Me2
anion near δ -0.6 and a triplet for the Ru-bound Me at
δ 1.11-1.34 (J PH ) 5.5-6.2 Hz), generally with the
appropriate 2:1 signal integration. The Me signal for the
fluorobenzene complex is actually a doublet of triplets
with an additional small coupling of 2.4 Hz. This is
presumably due to coupling of the Ru-Me hydrogens to
-
thiophene and the presence of AlCl2Me2 anions are
confirmed by single-crystal X-ray analysis for com-
pounds 1‚CH2Cl2 and 3‚CH2Cl2 (Figures 1 and 2; Tables
1 and 2). There are many structural studies of arene
coordination, and the X-ray structure of the cation of 1
is unexceptional. Although there are far fewer η5-
thiophene complexes, the structural features of the
thiophene ligand in 3 generally are similar to those
observed in other transition metal complexes containing
similarly bound thiophene and thiophene derivatives.7
Although it is not a significant feature of the structures,
the nature of the anion in 1 and 3 is somewhat more
problematic. From the X-ray data the molecular formula
calculates as AlCl2Me2-, which agrees with NMR inte-
gration of methyl groups and elemental analyses for the
most part, but may be a nominal composition where a
1
fluorine. The H signal for the η6-C6H6 ligand in 1 is a
singlet at δ 5.51. 13C NMR chemical shifts of the
coordinated arenes and thiophene in 1-4 all shift
upfield in comparison to those of the free arenes and
thiophene, which is typical for such ligands bound to
transition metals. For instance, coordinated thiophene
1
has H and 13C chemical shifts of δ 5.32 (CH), 5.86 (CH),
94.3 (CH), and 95.0 (CH), while the chemical shifts of
free thiophene are δ 7.31, 7.50, 123.8, and 125.5,
respectively. The 31P NMR chemical shifts range from
δ 42.0 to 48.5. The AlCl2Me2- counteranion in 1 can be
-
replaced by BArF ([B(3,5-(CF3)2C6H3)4]-) by reacting
[Ph3C][BArF]6 with 1 in CH2Cl2. The trityl cation
apparently removes a methyl group from the anion to
(5) Atwood, D. A.; Bott, S. G.; Atwood, J . L. J . Coord. Chem. 1987,
17, 93.
(6) Bahr, S. R.; Boudjouk, P. J . Org. Chem. 1992, 57, 5545.
(7) (a) Polam, J . R.; Porter, L. C. Organometallics 1993, 12, 3504,
and references therein. (b) Angelici, R. J . NATO ASI Ser., Ser. 3 1998,
60 (Transition Metal Sulphides), 89.

2338 Organometallics, Vol. 21, No. 11, 2002
Notes
Ta ble 1. Selected Bon d Len gth s (Å) a n d An gles
(d eg) for [(η6-C6H6)Ru (Me)(P P h 3)2]-
[AlMe2Cl2]‚CH2Cl2, 1‚CH2Cl2
recorded on a Varian Unity 300 spectrometer with field
1
strengths of 300, 121, and 75 MHz, respectively. H and 13C
chemical shifts were referenced to the residual solvent reso-
nance relative to TMS; 31P chemical shifts were referenced to
external 85% H3PO4. Elemental analyses were performed in
house on a Perkin-Elmer Series II CHNS/O model 2400
analyzer.
Ru-C(1)
2.124(9)
2.276(10)-2.334(13)
1.813
2.368(3)
2.402(3)
Ru-Cbenzene
Ru-centroidbenzene
Ru-P(2)
[(η6-Be n ze n e )b is(t r ip h e n ylp h osp h in e )(m e t h yl)r u -
th en iu m ][AlCl2Me2] (1). AlMe3 (2 M in hexane, 0.16 mL, 0.31
mmol) was added to a suspension of RuCl2(PPh3)3 (0.200 g,
0.208 mmol) in benzene (9 mL), and the resulting mixture was
stirred for 3 h at RT to give a yellow suspension. The
suspension was filtered, and the solid was washed with hexane
(3×) to give the product (0.150 g, 85%) as yellow solids. 1H
NMR (CDCl3): δ -0.57 (s, 6H), 1.24 (t, 3H, J PH ) 6.2 Hz), 5.51
(s, 6H), 7.07-7.42 (m, 30H). 31P NMR (CDCl3): δ 42.5. 13C
NMR (CD2Cl2): δ -17.2 (t, J ) 15.0 Hz), 97.4, 128.8 (t, J )
4.5 Hz), 131.0, 134.0 (t, J ) 4.3 Hz), 134.8 (t, J ) 22.7 Hz). 1H
NMR and elemental analysis indicated the presence of lattice
benzene. Anal. Calcd for C45H45AlCl2P2Ru‚0.2C6H6: C, 65.95;
H, 5.50. Found: C, 65.77; H, 5.74.
[(η6-Ben zen e)bis(tr ip h en ylp h osp h in e)(m eth yl)r u th en -
iu m ][BAr F ]. A solution of 1 (66 mg, 0.078 mmol) in CH2Cl2
(2 mL) was treated with [Ph3C][BArF]6 (90 mg, 0.081 mmol)
for 30 min. Volatiles were removed and the residue was
washed with hexane. 31P and 1H NMR spectra were similar
to that for 1 but showed the absence of the aluminate anion
Me signals. Anal. Calcd for C75H51F24P2BRu: C, 56.92; H, 3.22.
Found: C, 56.43; H, 3.85.
[(η6-Me sit yle n e )b is(t r ip h e n ylp h osp h in e )(m e t h yl)-
r u th en iu m ][AlCl2Me2] (2). AlMe3 (2 M in hexane, 0.16 mL,
0.31 mmol) was added to a suspension of RuCl2(PPh3)3 (0.158
g, 0.16 mmol) in mesitylene (2 mL), and the resulting mixture
was stirred for 3 h at RT to give a yellow suspension. The
suspension was filtered and the solid was washed with hexane
(3×) to give the product as yellow solids that contain mesityl-
ene. Crystallization from CH2Cl2/hexane at -30 °C afforded
the product (0.095 g, 67%) as yellow crystals containing a
lattice CH2Cl2 as indicated by 1H NMR and elemental analysis.
1H NMR (CDCl3): δ -0.58 (s, 6H), 1.11 (t, 3H, J PH ) 6.0 Hz),
1.75 (s, 9H), 5.22 (s, 3H), 5.33 (2H, CH2Cl2), 7.02-7.41 (m,
30H). 31P NMR (CDCl3): δ 48.2. 13C NMR (CD2Cl2): δ -8.9 (t,
J ) 4.9 Hz), 19.1, 95,8, 115.7, 128.4, 131.0, 133.5 (t, J ) 22.0
Hz), 134.8. Anal. Calcd for C48H51AlCl2P2Ru‚CH2Cl2: C, 60.43;
H, 5.45. Found: C, 60.34; H, 5.56.
Ru-P(1)
C-C (benzene)
Al-C (anion)
Al-Cl (anion)
1.391(18)-1.426(17)
2.004(9), 2.041(9)
2.198(5), 2.238(5)
C(1)-Ru-P(2)
C(1)-Ru-P(1)
P(2)-Ru-P(1)
C-Al-C (anion)
Cl-Al-Cl (anion)
C-Al-Cl (anion)
86.3(3)
89.8(3)
97.39(9)
109.2(5)
102.8(2)
107.3(3)-112.0(4)
Ta ble 2. Selected Bon d Len gth s (Å) a n d An gles
(d eg) for [(η5-Th iop h en e)Ru (Me)(P P h 3)2]-
[AlMe2Cl2]‚CH2Cl2, 3‚CH2Cl2
Ru(1)-C(41)
Ru(1)-S(1)
2.168(7)
2.515(2)
2.208(9)
2.245(8)
2.212(8)
2.241(7)
1.881
2.335(2)
2.346(2)
1.728(10)
1.756(9)
1.420(11)
1.450(12)
1.388(11)
Ru(1)-C(37)
Ru(1)-C(38)
Ru(1)-C(39)
Ru(1)-C(40)
Ru(1)-centroidthiophene
Ru(1)-P(2)
Ru(1)-P(1)
S(1)-C(37)
S(1)-C(40)
C(37)-C(38)
C(38)-C(39)
C(39)-C(40)
C(41)-Ru(1)-P(2)
C(41)-Ru(1)-P(1)
P(2)-Ru(1)-P(1)
87.0(2)
86.5(2)
103.05(8)
mix of AlCl3Me- and AlClMe3- anions could be present
to a minor degree. Temperature factors show some
disorder of the anion in the benzene structure and to a
greater extent in the thiophene structure, where it is
extensive enough that it could be modeled. Unfortu-
nately, it is not possible to know if the disorder is
-
positional (orientational difference of the AlCl2Me2
[(η5-Th iop h e n e )b is(t r ip h e n ylp h osp h in e )(m e t h yl)-
r u th en iu m ][AlCl2Me2] (3). AlMe3 (2 M in hexane, 0.15 mL,
0.30 mmol) was added to a suspension of RuCl2(PPh3)3 (0.100
g, 0.10 mmol) in hexane (3 mL) and thiophene (0.2 mL), and
the resulting mixture was stirred for 3 days at RT to give a
yellow suspension. The suspension was filtered and the solid
was washed with hexane (3×) to give the product (0.061 g,
from cell to cell) or substitutional (mixture of AlCl3Me-
and AlClMe3-). Most likely the dominant anion is
AlCl2Me2-, however, as in the previously mentioned
structure of [YbCl2(15-crown-5)][AlCl2Me2] (the anion
was not reported to be disordered here).5
In summary, a general one-pot synthesis of (arene)-
(PPh3)2(Me)Ru(II) cations has been developed, including
1
72%) as yellow solids. H NMR (CDCl3): δ -0.62 (s, 6H), 1.18
-
a η5-thiophene analogue. The AlCl2Me2 counteranion
(t, 3H, J PH ) 5.8 Hz), 5.36 (br, 2H), 5.86 (br, 2H), 7.03-7.44
(m, 30H). 31P NMR (CDCl3): δ 46.9. 13C NMR (CDCl3): δ -11.5
(br), 94.3, 95.0, 128.9, 130.8, 133.6, 134.1 (t, J ) 22.5 Hz). Anal.
Calcd for C43H43AlCl2P2SRu: C, 60.56; H, 5.04. Found: C,
59.72; H, 5.51.
in 1 can be replaced by BArF- by reaction with [Ph3C]-
[BArF], which removes a methyl group from the anion
rather than from the metal. X-ray analysis confirms the
η6-coordination of arene and η5-coordination of thiophene.
[(η6-F lu or oben zen e)bis(tr ip h en ylp h osp h in e)(m eth yl)-
r u th en iu m ][AlCl2Me2] (4). AlMe3 (2 M in hexane, 0.20 mL,
0.40 mmol) was added to a suspension of RuCl2(PPh3)3 (0.100
g, 0.10 mmol) in hexane (3 mL) and fluorobenzene (0.2 mL),
and the resulting mixture was stirred for 2 days at RT to give
a yellow suspension. The suspension was filtered and the solid
was washed with hexane (3×) to give a yellow solid. The solid
was crystallized from CH2Cl2/hexane to afford the product
Exp er im en ta l Section
All manipulations were performed either under a helium
atmosphere in a Vacuum Atmospheres drybox or under an
argon atmosphere using standard Schlenk techniques unless
otherwise specified. CH2Cl2 was distilled under Ar from P2O5.
Hexane was purified by passing through columns of activated
alumina and activated Cu-0226 S copper catalyst (Engelhard).
Benzene, mesitylene, and fluorobenzene were purchased from
Aldrich and dried under 4 Å molecular sieves. Other reagents
were purchased from Aldrich, Acros, Fluka, or Strem Chemical
Co. and used as received. 1H, 31P, and 13C spectra were
1
(0.060 g, 71%) as yellow solids. H NMR (CDCl3): δ -0.56 (s,
6H), 1.34 (dt, 3H, J PH ) 5.5 Hz; J FH ) 2.4 Hz), 4.43 (t, 2H, J
) 5.5 Hz), 5.50 (br, 2H), 6.50 (br, 1H), 7.05-7.45 (m, 30H).
31P NMR (CDCl3): δ 42.0. 13C NMR (CDCl3): δ -5.1 (br), 78.4
(d, J ) 19.2 Hz), 93.8, 100.6, 128.8, 131.2, 133.8. Although a

Notes
Organometallics, Vol. 21, No. 11, 2002 2339
Ta ble 3. Cr ysta l Da ta a n d Str u ctu r e Refin em en t
Ta ble 4. Cr ysta l Da ta a n d Str u ctu r e Refin em en t
for [(η5-Th iop h en e)Ru (Me)(P P h 3)2]-
[AlMe2Cl2]‚CH2Cl2, 3‚CH2Cl2
for [(η6-C6H6)Ru (Me)(P P h 3)2][AlMe2Cl2]‚CH2Cl2,
1‚CH2Cl2
empirical formula
fw
C46H47AlCl4P2Ru
931.63
empirical formula
fw
C44H45AlCl4P2RuS
937.65
temperature
wavelength
cryst syst
203(2) K
0.71073 Å
triclinic
temperature
wavelength
cryst syst
203(2) K
0.71073 Å
triclinic
space group
unit cell dimens
P1h
space group
unit cell dimens
P1h
a ) 11.856(2) Å, R ) 89.52(3)°
b ) 13.529(3) Å, â ) 84.92(3)°
c ) 15.098(3) Å, γ ) 68.94(3)°
2250.3(8) Å3
a ) 18.1777(11) Å, R ) 80.688(2)°
b ) 19.8036(9) Å, â ) 80.032(1)°
c ) 25.2070(13) Å, γ ) 78.652(1)°
8685.4(8) Å3
volume
volume
Z
2
Z
8
density (calcd)
abs coeff
1.375 Mg/m3
density (calcd)
abs coeff
1.434 Mg/m3
0.707 mm-1
0.780 mm-1
F(000)
cryst size
θ range for data collection
index ranges
956
F(000)
cryst size
θ range for data collection
index ranges
3840
0.19 × 0.11 × 0.05 mm3
0.29 × 0.21 × 0.12 mm3
1.61-22.46°
1.06-25.35°
-21 e h e 21, -23 e k e 23,
0 e l e 30
-12 e h e 12, -14 e k e 14,
-15 e l e 16
no. of reflns collected
no. of ind reflns
max. and min. transmn
refinement method
no. of data/restraints/params
goodness-of-fit on F2
final R indices [I>2σ(I)]
R indices (all data)
5846
no. of reflns collected
no. of ind reflns
max. and min. transmn
refinement method
33 002
4773 [R(int) ) 0.0714]
0.9655 and 0.8773
full-matrix least-squares on F2
4773/0/487
27825 [R(int) ) 0.0238]
0.9122 and 0.8054
full-matrix least-squares on F2
no. of data/restraints/params 27825/6/1499
1.072
goodness-of-fit on F2
final R indices [I>2σ(I)]
R indices (all data)
1.027
R1 ) 0.0660, wR2 ) 0.1578
R1 ) 0.1037, wR2 ) 0.2024
0.886 and -1.850 e Å-3
R1 ) 0.0820, wR2 ) 0.1945
R1 ) 0.1506, wR2 ) 0.2246
1.285 and -0.721 e Å-3
largest diff peak and hole
largest diff peak and hole
molecules were present in the unit cell, and the Supporting
Information presents data for all four (the C-C distances in
the phenyl rings of PPh3 were constrained to 1.3900 Å and
the C-C-C angles to 120°). Anomalous temperature factors
on the AlMe2Cl2 anions suggested disorder; the methyl carbon
atoms had very small anisotropic displacement parameters,
and the chloride atoms had moderately large anisotropic
displacement parameters. The carbon atom positions with
small ADPs were modeled as partial occupancy chlorine atoms,
with variable site occupancy factors tied to one. All hydrogen
atom positions in the (thiophene)Ru(Me)(PPh3)2 cation were
idealized and rode on the atom they were attached to.
Hydrogen atom positions of the disordered anions were not
included in the final model. Eight disordered dichloromethane
molecules were squeezed out of the unit cell (Z ) 8) using
PLATON/SQUEEZE.12 The final refinement included aniso-
tropic temperature factors on all non-hydrogen atoms, except
for the anion chloride and carbon atoms. The anisotropic
temperature factors of C(79), a thiophene carbon not bonded
to S, were restrained to approximate isotropic behavior to
prevent them from going nonpositive definite. Structure solu-
tion, refinement, graphics, and creation of publication materi-
als were as above. Additional details of data collection and
structure refinement are listed in Table 4.
satisfactory carbon analysis was not obtained possibly because
of the sensitive nature and/or mixed composition of the anion,
the NMR data are clean and analogous to that for 1-3.
X-r a y Cr ysta llogr a p h ic An a lyses. Crystals of 1‚CH2Cl2
were grown from CH2Cl2/hexane and mounted onto a glass
fiber using a spot of silicone grease. Due to air-sensitivity, the
crystal chosen was mounted from a pool of mineral oil under
argon gas flow. The crystal was placed on a Bruker P4/CCD
diffractometer, and cooled to 203 K using a Bruker LT-2
temperature device. The instrument was equipped with a
sealed, graphite-monochromatized Mo KR X-ray source (λ )
0.71073 Å). A hemisphere of data was collected using æ scans,
with 30 s frame exposures and 0.3° frame widths. Data
collection and initial indexing and cell refinement were
handled using SMART8 software. Frame integration, including
Lorentz-polarization corrections, and final cell parameter
calculations were carried out using SAINT9 software. The data
were corrected for absorption using the SADABS10 program.
Decay of reflection intensity was monitored via analysis of
redundant frames. The structure was solved using direct
methods and difference Fourier techniques. All hydrogen atom
positions were idealized and rode on the atom they were
attached to. The final refinement included anisotropic tem-
perature factors on all non-hydrogen atoms. Structure solution,
refinement, graphics, and creation of publication materials
were performed using SHELXTL NT.11 Additional details of
data collection and structure refinement are listed in Table 3.
Crystals of 3‚CH2Cl2 were grown from CH2Cl2/hexane, and
a yellow-orange, irregularly shaped crystal was mounted onto
a glass fiber using a spot of silicone grease. The data collection
and structure solution were as above. Four independent
Ack n ow led gm en t. We are grateful to the Depart-
ment of Energy, Office of Basic Energy Sciences, Chemi-
cal Sciences Division, for funding support.
Su p p or tin g In for m a tion Ava ila ble: X-ray crystallo-
graphic data of the structures of compounds 1‚CH2Cl2 and 3‚
CH2Cl2. This material is available free of charge via the
Internet at http://pubs.acs.org.
(8) SMART-NT 4; Bruker AXS, Inc.: Madison, WI 53719, 1996.
(9) SAINT-NT 5.050; Bruker AXS, Inc.: Madison, WI 53719, 1998.
(10) Sheldrick, G. SADABS, first release; University of Go¨ttingen:
Germany.
OM0200860
(11) SHELXTL NT, Version 5.10; Bruker AXS, Inc.: Madison, WI
53719, 1997.
(12) PLATON: Spek, A. L. Acta Crystallogr. 1990, A46, C34.