Mixed Sandwich Carborane/Thiamacrocycle Compounds. Synthesis and Characterization of 1-Ph-33,3-[9]aneS3-K 3-S,S′,S″-3,1,2-closo-RuC2B9H 10 and 1,2-Ph2-3,3,3-[9]aneS3-K 3-S,S′,S″,3,1,2-pseudocloso-RuC2B 9H9

Article abstract of DOI:10.1021/ic9601899

The reactions between [Ru([9]aneS₃)(MeCN)₃][CF₃SO₃] ₂, a useful source of the [Ru{[9]aneS₃-k³-S,S′,S″}]²⁺ fragment dication, and [Tl][TlC₂B₉H₁₀Ph] and [Tl][TlC₂B₉H₉Ph₂], respectively sources of the {C₂B₉H₁₀Ph}^2- and {C₂B₉H₉Ph₂}^2- fragment dianions, have afforded 1-Ph-3,3,3-[9]aneS₃-k ³-S,S′,S″-3,1,2-closo-RuC₂B₉H ₁₀, 1, and 1,2-Ph₂-3,3,3-[9]aneS₃-k ³-S,S′,S″-3,1,2-pseudocloso-RuC₂B ₉H₉, 2, the first reported examples of mixed thiamacrocyle/carborane compounds. Compounds 1 and 2 have been characterized by multinuclear (¹H, ¹¹B-{¹H}, and ¹³C{¹H}) WAR spectroscopy, and by single-crystal X-ray diffraction studies. Compound 1 [space group P1?, a = 10.3552(7) ?, b = 13.7960(18) ?, c = 15.9795(13) ?, α = 68.227(7)°, β= 82.983(5)°, γ = 82.496(7)°, R = 0.0377 for 5893 observed data] is a closo metal carborane, based on an icosahedron, in which the [9]andS₃ ligand has effective C₃, symmetry. In solution at room temperature the macrocyclic ligand of 1 undergoes rapid rotation about an axis through the metal carborane polyhedron, and it is likely that the cage phenyl group is also spinning, the two fluxional processes operating in concert via a geared-type mechanism. Compound 2 [space group Pbca, a = 16.771(3) ?, b = 16.907(3) ?, c = 17.757(4) ?, R = 0.0397 for 2946 observed data] is a pseudocloso metal carborane and has a polyhedral architecture characterized by C(1)?C(2) 2.504(7) ? and Ru(3)?B(6) 2.960(6) ?, as a consequence of intramolecular crowding between the phenyl cage substituents. Phenyl/thiamacrocycle intramolecular crowding affords the latter a conformation with effective C_s symmetry-indeed, the entire molecule is effectively mirror-symmetric. The weighted average ¹¹B chemical shift of 2 is δ +8.18 ppm, ca. 16 ppm to high frequency of that of 1. By ¹H and ¹³C{¹H} NMR spectroscopy it appears that the phenyl substituents of 2 spin at room temperature, but that the [9]aneS₃ ligand does not.

Full text of DOI:10.1021/ic9601899

4548
Inorg. Chem. 1996, 35, 4548-4554
Mixed Sandwich Carborane/Thiamacrocycle Compounds. Synthesis and Characterization
of 1-Ph-3,3,3-[9]aneS3-K3-S,S′,S′′-3,1,2-closo-RuC2B9H10 and
1,2-Ph2-3,3,3-[9]aneS3-K3-S,S′,S′′-3,1,2-pseudocloso-RuC2B9H9
†,‡
Alan J. Welch* and Andrew S. Weller
Department of Chemistry, Heriot-Watt University, Edinburgh EH14 4AS, U.K.
ReceiVed February 22, 1996X
The reactions between [Ru([9]aneS3)(MeCN)3][CF3SO3]2, a useful source of the [Ru{[9]aneS3-κ3-S,S′,S′′}]2+
fragment dication, and [Tl][TlC2B9H10Ph] and [Tl][TlC2B9H9Ph2], respectively sources of the {C2B9H10Ph}2-
and {C2B9H9Ph2}2- fragment dianions, have afforded 1-Ph-3,3,3-[9]aneS3-κ3-S,S′,S′′-3,1,2-closo-RuC2B9H10, 1,
and 1,2-Ph2-3,3,3-[9]aneS3-κ3-S,S′,S′′-3,1,2-pseudocloso-RuC2B9H9, 2, the first reported examples of mixed
thiamacrocyle/carborane compounds. Compounds 1 and 2 have been characterized by multinuclear (1H, 11B-
{1H}, and 13C{1H}) NMR spectroscopy, and by single-crystal X-ray diffraction studies. Compound 1 [space
group P1h, a ) 10.3552(7) Å, b ) 13.7960(18) Å, c ) 15.9795(13) Å, R ) 68.227(7)°, â ) 82.983(5)°, γ )
82.496(7)°, R ) 0.0377 for 5893 observed data] is a closo metal carborane, based on an icosahedron, in which
the [9]andS3 ligand has effective C3 symmetry. In solution at room temperature the macrocyclic ligand of 1
undergoes rapid rotation about an axis through the metal carborane polyhedron, and it is likely that the cage
phenyl group is also spinning, the two fluxional processes operating in concert Via a geared-type mechanism.
Compound 2 [space group Pbca, a ) 16.771(3) Å, b ) 16.907(3) Å, c ) 17.757(4) Å, R ) 0.0397 for 2946
observed data] is a pseudocloso metal carborane and has a polyhedral architecture characterized by C(1)‚‚‚C(2)
2.504(7) Å and Ru(3)‚‚‚B(6) 2.960(6) Å, as a consequence of intramolecular crowding between the phenyl cage
substituents. Phenyl/thiamacrocycle intramolecular crowding affords the latter a conformation with effective Cs
symmetrysindeed, the entire molecule is effectively mirror-symmetric. The weighted average 11B chemical shift
1
of 2 is δ +8.18 ppm, ca. 16 ppm to high frequency of that of 1. By H and 13C{1H} NMR spectroscopy it
appears that the phenyl substituents of 2 spin at room temperature, but that the [9]aneS3 ligand does not.
Introduction
The chemistry of transition metal sandwich compounds
bearing carborane ligands is a well-developed area; although
the first examples, [Fe(C2B9H11)2]-, and [Fe(C2B9H11)2]2-, were
described by Hawthorne more than 30 years ago,1a carborane
sandwich compounds (in the context of the present paper the
word “carborane” refers exclusively to the nido-icosahedral
{C2B9} fragment) are still relevant to the current literature.1b,c
The chemistry of “traditional” mixed sandwich carborane
Figure 1. Typical “mixed sandwich” compounds, with (a) cyclopen-
tadienyl and carborane ligands and (b) thiamacrocycle and arene ligands.
compounds (i.e. carborane ligand and cyclopentadiene, arene
or related ligand [e.g. tris(1-pyrazolyl)borate], sketched in Figure
1a) is both also well established and continues to attact
especially intriguing when R ) Ph, as steric congestion forces
attention.2 Recent work in this group3 has focused on aspects
the phenyl groups to lie essentially co-planar, levering the cage
of the structures and chemistries of mixed sandwich carborane
carbons apart and resulting in a pseudocloso structure.3a,d-f
At the same time much current interest attends the chemistry
compounds of the type [(η-L)M(C2B9H9PhR)] (L ) Cp, Cp*,
C9H7, C9Me7; M ) Ir, Rh. L ) C6H6, C6H3Me3-1,3,5, C6H4-
of thiamacrocycles,4 especially their coordination chemistry with
transition elements. Particular attention has been paid to the
ligand 1,4,7-trithiacyclononane ([9]aneS3), which can be loosely
compared with η-cyclopentadienide or η-arene ligands insofar
as it occupies three facial sites of a metal coordination sphere
Me-1-iPr-4, C6Me6; M ) Ru. R ) H, Me, Ph). These are
† [9]aneS3 ) 1,4,7-trithiacyclononane.
‡ Steric Effects in Heteroboranes. 13. For part 12 see ref 3f.
X Abstract published in AdVance ACS Abstracts, June 15, 1996.
(1) (a) Hawthorne, M. F.; Young, D. C.; Wegner, P. A. J. Am. Chem.
Soc. 1965, 87, 1818. (b) Yan, Y.-K.; Mingos, D. M. P.; Mu¨ller, T. E.;
Williams, D. J.; Kurmoo, M. J. Chem. Soc., Dalton Trans. 1994, 1735.
(c) Uhrhammer, R.; Su, Y.; Swenson, D. C.; Jordan, R. F. Inorg. Chem.
1994, 33, 4398.
(3) (a) Lewis, Z. G.; Welch, A. J. J. Organomet. Chem. 1992, 430, C45.
(b) Lewis, Z. G.; Reed, D.; Welch, A. J. J. Chem. Soc., Dalton Trans.
1992, 731. (c) Lewis, Z. G.; Welch, A. J. J. Organomet. Chem. 1992,
438, 353. (d) Cowie, J.; Reid, B. D.; Watmough, J. M. S.; Welch, A.
J. J. Organomet. Chem. 1994, 481, 282. (e) Brain, P. T.; Bu¨hl, M.;
Cowie, J.; Lewis, Z. G.; Welch, A. J. J. Chem. Soc., Dalton Trans.
1996, 231. (f) Gra¨dler, U.; Weller, A. S.; Welch, A. J.; Reed, D. J.
Chem. Soc., Dalton Trans. 1996, 335.
(4) (a) Cooper, S. R. Acc. Chem. Res. 1988, 21, 141. (b) Blake, A. J.;
Schro¨der, M. AdV. Inorg. Chem. 1990, 35, 1. (c) Cooper, S. R.; Rawle,
S. C. Struct. Bonding (Berlin) 1990, 72, 1. (d) Cooper, S. R., Ed.
Crown Compounds: Toward Future Applications; VCH Publishers:
New York, 1992.
(2) (a) Garcia, M. P.; Green, M.; Stone, F. G. A.; Somerville, R. G.; Welch,
A. J.; Briant, C. E.; Cox, D. N.; Mingos, D. M. P. J. Chem. Soc.,
Dalton Trans. 1985, 2343. (b) Smith, D. E.; Welch, A. J. Organo-
metallics 1986, 5, 760. (c) Schubert, D. M.; Knobler, C. B.;
Trofimenko, S.; Hawthorne, M. F. Inorg. Chem. 1990, 29, 2364. (d)
Arnold, J.; Johnson, S. E.; Knobler, C. B.; Hawthorne, M. F. J. Am.
Chem. Soc. 1992, 114, 3396. (e) Yan, Y.-K.; Mingos, D. M. P.; Mu¨ller,
T. E.; Williams, D. J.; Kurmoo, M. J. Chem. Soc., Dalton Trans. 1995,
2509.
S0020-1669(96)00189-9 CCC: $12.00 © 1996 American Chemical Society

Carborane/Thiamacrocycle Compounds
Inorganic Chemistry, Vol. 35, No. 16, 1996 4549
Table 1. Crystallographic Data for Compounds 1 and 2
and acts as a six-electron donor.4,5 In common with metal
carboranes, mixed sandwich compounds involving macrocyclic
and arene or cyclopentadienyl ligands have also been reported,
e.g. Figure 1b.6
1
2
formula
fw
C14H27B9S3Ru
489.9
C20H31B9S3Ru
565.2
In view of this it is surprising that, at least to our knowledge,
no mixed thiamacrocycle/carborane sandwich compounds have
been reported, although this appears to be a natural extension
to the chemistry of both areas.
We report herein details of the synthesis, characterization and
the solid state structures of two mixed sandwich macrocycle/
carborane compounds bearing the tridentate, facially coordinat-
ing, thiamacrocycle [9]aneS3 and the carborane fragments
{C2B9H10Ph} and {C2B9H9Ph2}.
cryst dimens, mm
cryst syst
space group
a, Å
b, Å
c, Å
0.5 × 0.3 × 0.2 0.4 × 0.4 × 0.3
triclinic
P1h
othorhombic
Pbca
10.3552(7)
13.7960(18)
15.9795(13)
68.227(7)
82.983(5)
82.496(7)
293
16.771(3)
16.907(3)
17.757(4)
90
90
90
293
5034.95
8
R, deg
â, deg
γ, deg
T, K
V, Å3
2095.08
4
Z
D
calc, g cm-3
1.553
1.04
1.493
0.88
Experimental Section
µ(Mo KR), mm-1
F(000), e
1. Synthesis. General Procedures. All manipulations were carried
out under a dry dinitrogen atmosphere, although both new compounds
appear to be indefinitely air-stable in the solid state. The compounds
[Tl][TlC2B9H9Ph2],3a [Tl][TlC2B9H10Ph],3d and [Ru([9]aneS3)(Me-
CN)3][CF3SO3]27 were prepared as described in the literature. MeOH
and dmso (HPLC grade, Aldrich) were stored over 3 and 4 Å molecular
sieves, respectively, and degassed prior to use. Diethyl ether was
distilled under dinitrogen from Na/benzophenone immediately prior to
use. The macrocycle [9]aneS3 was used as supplied by Aldrich. 1H
NMR spectra were recorded on a Bru¨ker AC 200 spectrometer. 11B-
{1H} and 13C{1H} NMR spectra were recorded on a Bru¨ker DPX 400
spectrometer at 128.4 and 100.6 MHz respectively. 1H and 13C{1H}
NMR spectra were referenced to residual protio solvent in the sample;
11B{1H} NMR spectra were referenced to BF3‚OEt2 (external). All
NMR spectra were recorded from dmso-d6 solutions at room temper-
ature.
1-Ph-3,3,3-[9]aneS3-κ3-S,S′,S′′-3,1,2-closo-RuC2B9H10 (1). [Ru([9]-
aneS3)(MeCN)3][CF3SO3]2 (0.085 g, 0.12 mmol) and [Tl][TlC2B9H10-
Ph] (0.089 g, 0.14 mmol) were suspended in MeOH (10 cm3) and heated
to reflux for 3 h. The resulting supernatant liquid was removed Via
syringe and the brown solid remaining washed twice with MeOH and
once with diethyl ether and then dried in Vacuo. Recrystallization from
dmso/MeOH afforded brown plates of diffraction quality; mass 0.033
g, yield 56%.
992
4 - 50
7245
2304
4 - 50
4395
2θ range, deg
no. of unique data collcd
h range
k range
l range
-1 to 12
-15 to 15
-18 to 18
0.0557
-1 to 19
-1 to 20
-1 to 21
0.0770
2946
R (all data)
no. of data obsd [|Fo| > 4σ(|Fo|)] 5893
R (obsd data)a
0.0377
0.0397
0.1138
0.905
0.0576
6.53
b
wR2
0.0947
1.107
0.0340
5.06
Sc
g1
g2
max residue, e Å-3
min residue, e Å-3
+0.42
-0.45
+0.47
-0.41
a R ) ∑||Fo| - |Fc||/∑|Fo|. b wR2 ) [∑[w(Fo2 - Fc2)2]/∑[w(Fo )2]]1/2
.
2
2
c S ) [∑[w(Fo - Fc2)2]/(n - p)]1/2 where n ) number data and p )
number of variables.
1H NMR: δ 7.27 (d, 2H, ortho Ph), 7.14 (app t, 2H, meta Ph), 6.98
(t, 1H, para Ph), 2.85-2.27 (m, 8 H, [9]aneS3), 2.10 (m, 2 H, [9]-
aneS3), 1.12 (m, 2 H, [9]aneS3) ppm.
11B{1H} NMR: δ 28.5 (1 B), 18.0 (2B), 13.2 (1 B), 4.5 (2 B), 2.0
(2 B), -17.1 (1 B) ppm.
13C{1H} NMR: δ 152.7 (1C, Ph), 128.0 (2C, Ph), 125.7 (2C, Ph),
124.6 (1C, Ph), 36.7 (2C, [9]aneS3), 36.5 (2C, [9]aneS3), 32.4 (2C,
[9]aneS3) ppm.
Anal. Calcd for C14H27B9S3Ru: C, 34.4; H, 5.5. Found: C, 32.2;
H, 5.2 (incomplete combustion).
1H NMR: δ 7.14-6.90 (m, 5 H, Ph), 4.57 (s br, 1 H, CH), 2.75 (m,
3 H, [9]aneS3), 2.60 (m, 3 H, [9]aneS3) (multiplet partially obscured
by solvent peak) , 2.18 (m, 3 H, [9]aneS3), 1.68 (m, 3 H, [9]aneS3)
ppm.
2. X-ray Crystallography. Intensity measurements on 1 and 2
were made by ω scans at room temperature using a Siemens P4
diffractometer with graphite-monochromated Mo KR X-radiation (λbar
) 0.710 73 Å). Relevant crystallographic data are given in Table 1.
Periodic remeasurement of three standard reflections revealed no crystal
or electronic instability in either case. Intensity data were corrected
for the effects of X-ray absorption by ψ-scans.
11B{1H} NMR: δ 2.11 (1 B), -0.25 (1 B), -3.44 (1 B), -5.46 (1
B), -7.22 (1 B), -12.52 (3 B), -23.24 (1 B) ppm.
13C{1H} NMR: δ 147.4 (1C, Ph), 128.0 (4C, Ph), 124.0 (1C, Ph),
36.0 (3C, [9]aneS3), 31.5 (3C, [9]aneS3) ppm.
1,2-Ph2-3,3,3-[9]aneS3-K3-S,S′,S′′-3,1,2-pseudocloso-RuC2B9H9 (2).
Similarly, [Ru([9]aneS3)(MeCN)3][CF3SO3]2 (0.083 g, 0.12 mmol) and
[Tl][TlC2B9H9Ph2] (0.100 g, 0.14 mmol) were suspended in MeOH
(10 cm3) and heated to reflux for 3 h. The resulting supernatant liquid
was removed Via syringe, and the purple solid which remained was
washed twice with MeOH and once with diethyl ether and then dried
in Vacuo. Recrystallization from dmso/MeOH afforded purple blocks
of diffraction quality; mass 0.030 g, yield 46%.
The structures were solved without difficulty by direct methods and
refined by full-matrix least-squares, using SHELXTL.8 In the case of
compound 1 the Ccage atom not carrying the phenyl substituent, C(2),
was unambiguously identified by a combination of interatomic distances
and refined (as B) with isotropic thermal parameters. In both cases all
H atoms were located. For 1 those attached to cage atoms were
positionally refined, resulting in X-H 0.97(3)-1.15(3) Å, whereas for
2 B-H distances were constrained to a common value of 1.10(3) Å;
for both determinations cage H atoms were refined with individual
isotropic thermal parameters. Methylene-H and phenyl-H atoms were
constrained to idealized positions (C-H ) 0.97 and 0.93 Å respectively)
and given isotropic displacement parameters riding at 1.2U(C). All
non-H atoms were refined with anisotropic displacement parameters.
Anal. Calcd for C20H31B9S3Ru: C, 42.4; H, 5.5. Found: C, 40.9,
H, 5.1 (incomplete combustion).
(5) (a) Schro¨der, M. Pure Appl. Chem. 1988, 60, 517. (b) Alcock, N. W.;
Cannadine, J. C.; Clark, G. R.; Hill, A. F. J. Chem. Soc., Dalton Trans.
1993, 1131. (c) Hector, A. L.; Hill, F. H. Inorg. Chem. 1995, 34, 3797.
(6) (a) Blake, A. J.; Crofts, R. D.; Reid, G.; Schro¨der, M. J. Organomet.
Chem. 1989, 359, 371. (b) Bennett, M. A.; Goh, L. Y.; Willis, A. C.
J. Chem. Soc., Chem. Commun. 1992, 1180. (c) Bell, M. N.; Blake,
A. J.; Christie, R. M.; Gould, R. O.; Holder, A. J.; Hyde, T. I.;
Schro¨der, M.; Yellowless, L. J. J. Chem. Soc., Dalton Trans. 1992,
2977.
In the final stages of refinement data were weighted such that w-1
)
2
2
[σ2(Fo ) + (g1P)2 + g2P] where P ) [max(Fo or 0) + 2Fc2]/3.
Positional parameters for compounds 1 and 2, together with
equivalent isotropic thermal parameters, are listed in Tables 2 and 3,
respectively. Hydrogen atom coordinates and displacement parameters,
(7) Landgrafe, C.; Sheldrick, W. S. J. Chem. Soc., Dalton Trans. 1994,
1885.
(8) SHELXTL PC version 5.0,. Siemens Analytical Instruments Inc.,
Madison, WI, 1994.

4550 Inorganic Chemistry, Vol. 35, No. 16, 1996
Welch and Weller
Table 2. Atomic Coordinates (×105 Ru, S; ×104 B, C) and
Table 3. Atomic Coordinates (×105 Ru, S; ×104 B, C) and
Equivalent Isotropic Displacement Parameters (Å2 × 103) for 1
Equivalent Isotropic Displacement Parameters (Å2 × 103) for 2
x
y
z
U(eq)a
x
y
z
U(eq)a
Ru(3)
S(1)
S(2)
S(3)
C(1)
C(2)
B(4)
B(5)
B(6)
84457(3)
81133(12)
65440(12)
70464(11)
9241(4)
9562(5)
9769(5)
10687(5)
10526(5)
10285(6)
10491(5)
11505(5)
11939(5)
11199(6)
11813(5)
8157(4)
7627(5)
6603(6)
6108(6)
6615(6)
7639(5)
7078(6)
5965(6)
5313(5)
5366(5)
7063(6)
6962(5)
88302(3)
107467(11)
96663(12)
99846(12)
6800(4)
7088(5)
7323(5)
5621(6)
5482(5)
7807(6)
7936(6)
6301(6)
5188(6)
6098(6)
6602(6)
6736(4)
6616(5)
6602(6)
6695(6)
6813(6)
6834(5)
11325(5)
11265(5)
10158(6)
10852(5)
11362(5)
11990(5)
2642(3)
14150(10)
11365(11)
-7790(10)
-659(4)
609(4)
-1170(4)
-1435(4)
-320(5)
1002(5)
-167(5)
-1122(5)
-580(5)
716(5)
20241(2)
5644(8)
24941(8)
17806(8)
3327(3)
2928(3)
2487(4)
3444(4)
3728(4)
1843(4)
1537(4)
2344(4)
3107(4)
2811(4)
1948(4)
4055(3)
4599(4)
5249(4)
5356(4)
4831(4)
4178(3)
745(4)
21(1)
30(1)
32(1)
29(1)
23(1)
29(1)
26(1)
27(1)
31(1)
34(1)
30(1)
29(1)
30(1)
32(1)
30(1)
27(1)
41(1)
57(2)
59(2)
52(2)
37(1)
40(1)
41(1)
40(1)
39(1)
37(1)
36(1)
22(1)
28(1)
32(1)
31(1)
25(1)
29(1)
28(1)
35(1)
32(1)
31(1)
29(1)
34(1)
33(1)
33(1)
33(1)
30(1)
43(1)
54(2)
55(2)
56(2)
40(1)
33(1)
37(1)
41(1)
42(1)
34(1)
33(1)
Ru(3)
S(1)
S(2)
S(3)
C(1)
C(2)
B(4)
B(5)
B(6)
88981(2)
95431(8)
89708(9)
101955(8)
7713(3)
8672(3)
7676(4)
6974(3)
7667(3)
8831(4)
8271(4)
7222(4)
7152(4)
8099(4)
7900(5)
9474(5)
9534(6)
9675(5)
10230(6)
10887(4)
10595(4)
7520(3)
7492(4)
7310(5)
7130(5)
7142(4)
7349(4)
9213(3)
9967(3)
10465(4)
10248(4)
9511(4)
9015(3)
21104(2)
9522(8)
26998(10)
26380(9)
1606(3)
1558(3)
2562(4)
1993(4)
1345(4)
2505(4)
3133(4)
2984(4)
2229(4)
1945(4)
2947(4)
1069(4)
1891(5)
3418(5)
3424(6)
1903(5)
1119(4)
1007(3)
207(3)
-334(4)
-82(4)
713(4)
1246(4)
912(3)
1090(4)
497(4)
-288(4)
-473(4)
117(3)
41415(2)
46420(8)
53875(8)
40245(9)
4136(3)
3056(3)
4256(4)
3689(4)
3194(4)
2965(3)
3608(4)
3418(5)
2750(4)
2432(4)
2669(4)
5650(3)
5943(4)
5327(4)
4718(6)
4397(6)
4468(5)
4729(3)
4584(4)
5148(4)
5855(4)
6019(3)
5464(3)
2805(3)
2511(4)
2268(4)
2313(4)
2593(3)
2843(3)
25(1)
38(1)
48(1)
44(1)
30(1)
29(1)
35(1)
40(2)
35(1)
38(1)
39(2)
49(2)
50(2)
43(2)
52(2)
69(2)
88(3)
80(2)
113(4)
109(4)
72(2)
32(1)
53(2)
69(2)
67(2)
59(2)
47(2)
33(1)
55(2)
73(2)
61(2)
52(2)
42(1)
B(7)
B(8)
B(9)
B(7)
B(8)
B(9)
B(10)
B(11)
B(12)
C(31)
C(32)
C(33)
C(34)
C(35)
C(36)
C(21)
C(22)
C(23)
C(24)
C(25)
C(26)
Ru(3′)
S(1′)
B(10)
B(11)
B(12)
C(21)
C(22)
C(23)
C(24)
C(25)
C(26)
C(101)
C(102)
C(103)
C(104)
C(105)
C(106)
C(201)
C(202)
C(203)
C(204)
C(205)
C(206)
216(5)
-1046(4)
-487(5)
-845(7)
-1752(6)
-2325(6)
-1976(4)
2501(4)
2170(5)
213(5)
1473(4)
2740(4)
2056(4)
547(3)
-301(5)
-310(4)
863(4)
113(3)
52164(3)
57960(9)
55131(11)
35625(10)
5003(4)
6268(4)
4407(5)
4780(5)
5948(5)
6591(5)
5374(5)
5022(5)
5985(5)
6930(5)
6370(5)
4439(4)
4963(5)
4413(6)
3348(6)
2816(6)
3346(5)
6548(4)
6018(4)
4198(5)
3488(5)
3659(4)
4658(4)
21068(2)
12489(8)
32927(8)
26320(8)
2647(3)
2168(3)
1853(4)
2085(4)
2293(4)
1081(4)
841(4)
S(2′)
S(3′)
C(1′)
C(2′)
B(4′)
B(5′)
B(6′)
B(7′)
B(8′)
B(9′)
B(10′)
B(11′)
B(12′)
C(31′)
C(32′)
C(33′)
C(34′)
C(35′)
C(36′)
C(21′)
C(22′)
C(23′)
C(24′)
C(25′)
C(26′)
a Equivalent isotropic U defined as one-third of the trace of the
orthogonalized Uij tensor.
3,3,3-[9]aneS3-κ3-S,S′,S′′-3,1,2-pseudocloso-RuC2B9H9, 2, re-
spectively, in moderate yield. Although both 1 and 2 were
initially characterized by multinuclear (1H, 11B, and 13C) NMR
spectroscopies, the spectra, particularly in the context of the
fluxionality of 1 and the partial fluxionality of 2 in solution,
are best related to the respective molecular structures established
crystallographically. Discussion of the NMR data is therefore
deferred until after the results of the appropriate diffraction study
have been presented. Recrystallization of both compounds 1
and 2 from dmso/methanol afforded brown plates and purple
blocks, respectively, which were suitable for single-crystal X-ray
diffraction studies.
Two independent molecules of compound 1 crystallize in the
asymmetric fraction of the unit cell. The molecule is chiral,
but the space group is centrosymmetric with equal numbers of
molecules of each hand. Figure 2 shows similar views of both
crystallographically-independent molecules and demonstrates the
atomic numbering scheme. Table 4 lists selected interatomic
distances (except those involving H atoms) and interbond angles
determined. There is no chemically significant difference
between the two independent molecules, so for convenience
parameters are discussed for the molecule involving Ru(3) only,
with data in square brackets representing differences in respect
of the molecule involving Ru(3′).
959(4)
1231(4)
1320(4)
480(4)
3652(3)
4249(4)
5173(4)
5513(4)
4932(4)
4000(4)
1829(4)
2843(4)
4073(4)
3600(4)
1777(4)
1503(4)
a Equivalent isotropic U defined as one-third of the trace of the
orthogonalized Uij tensor.
non-hydrogen atom thermal parameters, and a full listing of interatomic
distances and interbond angles (except those involving H atoms) are
available as Supporting Information.
Results and Discussion
Reflux of a methanolic solution of the recently reported
complex [Ru{[9]aneS3-κ3-S,S′,S′′}(NCMe)3][CF3SO3]2,7 pre-
pared from [RuCl2{[9]aneS3-κ3-S,S′,S′′}(dmso)][CF3SO3] and
[Ag][CF3SO3] (dmso ) dimethyl sulfoxide), with a slight excess
of the thallium salts [Tl][TlC2B9H10Ph] and [Tl][TlC2B9H9Ph2]
(effectively [7-Ph-7,8-nido-C2B9H10]2- and [7,8-Ph2-7,8-nido-
C2B9H9]2-), results in the precipitation of the first examples of
mixed sandwich carborane/thiamacrocycle compounds 1-Ph-
3,3,3-[9]aneS3-κ3-S,S′,S′′-3,1,2-closo-RuC2B9H10, 1, and 1,2-Ph2-
The {RuC2B9} portion of the molecule has the closo
icosahedral structure anticipated by empirical electron counting
rules.9 The mean Ru-B and Ru-C distances, 2.217 and 2.181
[2.226 and 2.183] Å are marginally longer than those, 2.205
and 2.169 Å, respectively, in the related species 1-Ph-3-(mes)-
(9) Wade, K. AdV. Inorg. Chem. Radiochem. 1976, 18, 1.

Carborane/Thiamacrocycle Compounds
Inorganic Chemistry, Vol. 35, No. 16, 1996 4551
Figure 2. Crystallographically-independent molecules of compound 1. Thermal elipsoids were drawn at the 30% probability level. H atoms have
an artificial radius of 0.1 Å for clarity. The phenyl ring was numbered cyclically. H atoms of the phenyl carborane ligand carry the same number
as the atom to which they are attached.
3d
3,1,2-closo-RuC2B9H10 (mes ) C6H3Me3-1,3,5), but the
pattern of distances is similar, with Ru-C(1) > Ru-C(2) and
Ru-B(8) the longest Ru-B. Within the carborane ligand the
relative lengths of the connectivities are as expected, with C(1)-
C(2) 1.688(7) [1.677(7)] Å, C-B 1.702(7)-1.742(7) [1.702(7)-
1.751(7)] Å, and B-B 1.740(8)-1.832(9) [1.741(8)-1.841(8)]
Å. The conformation of the phenyl substituent (θ), defined3d
as the modulus of the average Ccage-Ccage-C-C torsion angle,
is 71.0(4) [74.4(4)]°, in excellent accord with that recently
measured in the parent carborane 1-Ph-1,2-closo-C2B10H11 (65-
70°) both in the gaseous phase10 and in two crystalline
modifications.10,11 The closest intramolecular approach between
carborane and [9]aneS3 ligands involves the endo-H atom bound
to C(23) which lies only 2.82 [2.74] Å above the phenyl ring
plane. Figure 3, a space-filling representation of compound 1,
shows that this contact is just at the van der Waals sum.
In compound 1 the {Ru[9]aneS3} fragment has near C3
symmetry with the sulfur atoms coordinated to Ru(3) in tris-
endodentate fashion and staggered conformations about the C-C
bonds. Although Ru-S distances and S-Ru-S angles are
broadly similar to those previously observed in {RuII[9]aneS3}
fragments,5b,7,12 close inspection reveals that Ru-S(2) is
significantly the longest, and presumably the weakest, such
bond. In that Ru-S(2) lies effectively cis to cage carbon atoms
and consequently effectively trans to cage boron atoms, its
relative weakness can be ascribed to the differeing trans
influences of Ccage and Bcage in such systems established by
previous structural studies.2a,3d,13 The [9]aneS3 ligand displays
staggered conformations about all three C-C bonds, with
S-C-C-S torsion angles of 47.3(5), 46.4(5), and 47.8(5)
[-47.7(5), -46.5(5), and -48.1(5)]°.
chemical shifts, +2.1 to -23.2 ppm, is fully consistent with a
metal carborane compound with a closo structure.3b,e,f The 1H
NMR spectrum displays the expected resonances due to the cage
C-H atom and the aromatic protons of one phenyl group.
However, only four multiplets, each with an integral equivalent
to three protons, are observed between 2.8 and 1.6 ppm
attributable to the thioether methylene groups [we ascribe the
lowest frequency methylene signal to the endo protons bound
to C(21), C(23) and C(25) as a consequence of the proximity
ot the cage phenyl ring]. Moreover, the 13C{1H} NMR spectrum
displays only two signals (36.0 and 31.5 ppm) due to the
methylene carbon atoms. If the macrocycle were static [that is
to say not spinning about the molecular axis from Ru(3) to
B(10)], then six signals would be observed in the 13C{1H} NMR
spectrum due to the reduction in symmetry imposed by the
asymmetric carborane moiety. However, if rotation about this
axis occurs at a rate which is faster than the NMR time scale
only two signals of equal intensity would be expected, due to
the equivalence of two sets of three carbon atoms (Figure 4).
Such rotation is also fully consistent with the observation in
1
the H NMR spectrum of only four equal integral multiplets
arising from the methylene groups of the [9]aneS3 ligand, each
of the two magnetically-inequivalent C atoms carrying non-
interconverting exo and an endo protons.
Only three signals, in the ratio 1:4:1, are observed in the
phenyl region of the 13C{1H} NMR spectrum of compound 1
at 100.6 MHz. Assuming that the central resonance represents
a coincidence this observation is consistent with a rotation of
the pendant phenyl group about the C(1)-C(31) bond which is
rapid on the NMR time scale at room temperature (a static
phenyl group would necessitate the assumption of a quadruply
coincident resonance). We suggest that the clear fluxionality
of the thioether ligand, and the likely fluxionality of the cage
phenyl group, in 1 are correlated, the phenyl group locking into
gaps [e.g. between S(3) and the endo-H atom on C(23)] in the
van der Waals surface of the macrocycle in a geared type
rotation.14 All attempts to arrest this fluxionality have been
frustrated by the insolubility of the compound in solvents other
than dmso.
The 11B{1H} NMR spectrum of compound 1 is fully
consistent with the crystallographically-determined molecular
structure, there being seven signals of relative integration 1:1:
1:1:1:3:1 (high frequency to low frequency), the penultimate
signal representing a triple coincidence. The range of 11B
(10) Brain, P. T.; Cowie, J.; Donohoe, D. J.; Hnyk, D.; Rankin, D. W. H.;
Reed, D.; Reid, B. R.; Robertson, H. E.; Welch, A. J.; Hofmann, M.;
Schleyer, P. v. R. Inorg. Chem. 1996, 35, 1701.
(11) Thomas, R. Ll.; Rosair, G. M.; Welch, A. J. Acta Crystallogr., Sect.
C 1996, 52, 1024.
(12) (a) Bell, M. N.; Blake, A. J.; Schro¨der, M.; Ku¨ppers, H.-J.; Wieghardt,
K. Angew. Chem., Int. Ed. Engl. 1987, 26, 250. (b) Adams, R. D.;
Yamamoto, J. H. Organometallics 1995, 14, 3704.
(13) Barker, G. K.; Garcia, M. P.; Green, M.; Pain, G. N.; Stone, F. G. A.;
Jones, S. K. R.; Welch, A. J. J. Chem. Soc., Chem. Commun. 1981,
652 and references therein.
A perspective view of a single molecule of compound 2 is
presented in Figure 5, and Table 5 lists selected interatomic
distances and interbond angles determined. The molecule has
near-mirror symmetry about the plane containing Ru(3), B(8),
B(6), and B(10).

4552 Inorganic Chemistry, Vol. 35, No. 16, 1996
Welch and Weller
Table 4. Selected Interatomic Distances (Å) and Interbond Angles
(deg) for 1
Ru(3)-C(1)
Ru(3)-C(2)
Ru(3)-B(4)
Ru(3)-B(7)
Ru(3)-B(8)
Ru(3)-S(1)
Ru(3)-S(3)
Ru(3)-S(2)
S(1)-C(21)
S(1)-C(26)
S(2)-C(22)
S(2)-C(23)
S(3)-C(25)
S(3)-C(24)
C(1)-C(31)
C(1)-C(2)
C(1)-B(5)
C(1)-B(6)
C(1)-B(4)
C(2)-B(11)
C(2)-B(7)
C(2)-B(6)
B(4)-B(9)
B(4)-B(8)
B(4)-B(5)
B(5)-B(6)
B(5)-B(10)
B(5)-B(9)
B(6)-B(10)
B(6)-B(11)
B(7)-B(12)
B(7)-B(11)
B(7)-B(8)
B(8)-B(9)
B(8)-B(12)
B(9)-B(12)
B(9)-B(10)
B(10)-B(11)
B(10)-B(12)
B(11)-B(12)
C(21)-C(22)
C(23)-C(24)
C(25)-C(26)
2.193(4)
2.170(5)
2.189(5)
2.214(6)
2.249(5)
2.3207(12)
2.3280(13)
2.3623(12)
1.817(5)
1.837(5)
1.829(5)
1.826(6)
1.831(5)
1.840(5)
1.508(6)
1.688(7)
1.710(7)
1.731(7)
1.737(7)
1.702(7)
1.718(8)
1.742(7)
1.791(7)
1.792(8)
1.797(7)
1.742(8)
1.766(8)
1.779(8)
1.740(8)
1.769(8)
1.785(8)
1.803(8)
1.832(9)
1.791(8)
1.803(8)
1.774(8)
1.773(8)
1.764(8)
1.779(8)
1.777(8)
1.518(8)
1.500(8)
1.501(8)
Ru(3′)-C(1′)
Ru(3′)-C(2′)
Ru(3′)-B(4′)
Ru(3′)-B(7′)
Ru(3′)-B(8′)
Ru(3′)-S(1′)
Ru(3′)-S(3′)
Ru(3′)-S(2′)
S(1′)-C(21′)
S(1′)-C(26′)
S(2′)-C(22′)
S(2′)-C(23′)
S(3′)-C(25′)
S(3′)-C(24′)
C(1′)-C(31′)
C(1′)-C(2′)
C(1′)-B(5′)
C(1′)-B(6′)
C(1′)-B(4′)
C(2′)-B(11′)
C(2′)-B(7′)
C(2′)-B(6′)
B(4′)-B(9′)
B(4′)-B(8′)
B(4′)-B(5′)
B(5′)-B(6′)
B(5′)-B(10′)
B(5′)-B(9′)
B(6′)-B(10′)
B(6′)-B(11′)
B(7′)-B(12′)
B(7′)-B(11′)
B(7′)-B(8′)
B(8′)-B(9′)
B(8′)-B(12′)
B(9′)-B(12′)
B(9′)-B(10′)
B(10′)-B(11′)
B(10′)-B(12′)
B(11′)-B(12′)
C(21′)-C(22′)
C(23′)-C(24′)
C(25′)-C(26′)
2.186(4)
2.179(5)
2.190(5)
2.236(5)
2.252(5)
2.3224(12)
2.3349(13)
2.3616(13)
1.818(5)
1.847(5)
1.838(5)
1.828(6)
1.833(5)
1.845(6)
1.499(6)
1.677(7)
1.721(7)
1.750(7)
1.751(7)
1.702(7)
1.722(8)
1.745(7)
1.766(7)
1.780(8)
1.803(8)
1.748(9)
1.761(8)
1.776(8)
1.741(8)
1.756(8)
1.783(8)
1.802(8)
1.841(8)
1.791(8)
1.799(8)
1.783(9)
1.786(9)
1.760(8)
1.780(8)
1.778(9)
1.508(8)
1.511(8)
1.495(7)
Figure 3. Space-filling representation of compound 1 [molecule
containing Ru(3)]. van der Waals radii used (Å): S, 1.80; B, 1.70; H,
1.20; C(non-Ph), 1.70; C(Ph), 1.85.
Figure 4. Rotation of the [9]aneS3 ligand in compound 1. Dashed
C(2′)-Ru(3′)-C(1′)
C(1)-Ru(3)-B(4)
C(2)-Ru(3)-B(7)
B(4)-Ru(3)-B(8)
B(7)-Ru(3)-B(8)
S(1)-Ru(3)-S(3)
S(1)-Ru(3)-S(2)
S(3)-Ru(3)-S(2)
C(21)-S(1)-C(26)
C(21)-S(1)-Ru(3)
C(26)-S(1)-Ru(3)
C(22)-S(2)-C(23)
C(22)-S(2)-Ru(3)
45.2(2) C(2)-Ru(3)-C(1)
46.7(2) C(1′)-Ru(3′)-B(4′)
46.1(2) C(2′)-Ru(3′)-B(7′)
47.6(2) B(4′)-Ru(3′)-B(8′)
48.5(2) B(7′)-Ru(3′)-B(8′)
86.49(5) S(1′)-Ru(3′)-S(3′)
86.81(5) S(1′)-Ru(3′)-S(2′)
86.27(5) S(3′)-Ru(3′)-S(2′)
45.5(2)
47.2(2)
45.9(2)
47.2(2)
48.4(2)
86.37(4)
86.73(4)
85.99(5)
lines indicate upper face of carborane ligand.
100.8(3) C(21′)-S(1′)-C(26′) 100.9(2)
103.1(2) C(21′)-S(1′)-Ru(3′) 103.0(2)
107.4(2) C(26′)-S(1′)-Ru(3′) 107.2(2)
100.8(3) C(22′)-S(2′)-C(23′) 101.2(3)
106.3(2) C(22′)-S(2′)-Ru(3′) 106.2(2)
C(23′)-S(2′)-Ru(3′) 104.0(2) C(23)-S(2)-Ru(3)
103.5(2)
C(25)-S(3)-C(24)
C(25)-S(3)-Ru(3)
C(24)-S(3)-Ru(3)
C(22)-C(21)-S(1)
C(21)-C(22)-S(2)
C(24)-C(23)-S(2)
C(23)-C(24)-S(3)
C(26)-C(25)-S(3)
C(25)-C(26)-S(1)
99.8(3) C(25′)-S(3′)-C(24′) 100.2(3)
103.5(2) C(25′)-S(3′)-Ru(3′) 103.5(2)
107.4(2) C(24′)-S(3′)-Ru(3′) 107.6(2)
114.2(4) C(22′)-C(21′)-S(1′) 114.2(4)
111.1(4) C(21′)-C(22′)-S(2′) 111.0(3)
113.7(4) C(24′)-C(23′)-S(2′) 113.1(4)
111.8(4) C(23′)-C(24′)-S(3′) 111.6(4)
113.1(4) C(26′)-C(25′)-S(3′) 113.0(4)
110.7(4) C(25′)-C(26′)-S(1′) 110.8(3)
Figure 5. Perspective view of compound 2. Construction and labeling
conventions are as in Figure 2.
It is immediately apparent that 2 is a pseudocloso metal
carborane.3a,e,f Although in the parent carborane 1,2-Ph2-1,2-
closo-C2B10H1015 the phenyl rings adopt conformations defined
by very low θ values (average θ for two crystallographically-
independent molecules with no imposed symmetry is 5.5°) the
phenyl groups in 2 are required to have high θ values [θC(101-106)
) 53.4(4), θC(201-206) ) 53.9(4)o] by the steric demands of the
[9]aneS3 ligand, and the Ph‚‚‚Ph repulsion thus generated results
in stretching of the C(1)-C(2) connectivity to 2.504(7) Å.
Figure 6, a space-filling representation of 2 in the same
orientation as Figure 5, clearly shows touching phenyl rings
even with C(1)‚‚‚C(2) extended [H(102)‚‚‚H(206) is 2.43 Å].
Prizing open the C(1)-C(2) connectivity is accompanied by a
shortening of the the Ru(3)‚‚‚B(6) distance, to 2.960(6) Å, the
overall result being the formation of a nearly square C(1)-
Ru(3)C(2)B(6) polyhedral face. Figure 7 contrasts key molec-
ular parameters in this four-atom fragment of compound 1
(14) Mislow, K.; Iwamura, H. Acc. Chem. Res. 1988, 21, 175 and references
therein.
(15) Lewis, Z. G.; Welch, A. J. Acta Crystallogr., Sect. C 1993, 49, 705.

Carborane/Thiamacrocycle Compounds
Inorganic Chemistry, Vol. 35, No. 16, 1996 4553
Figure 6. Space-filling representation of a single molecule of
compound 2. Radii are as in Figure 3.
Table 5. Selected Interatomic Distances (Å) and Interbond Angles
(deg) for 2
Ru(3)-C(1)
Ru(3)-B(7)
Ru(3)-B(8)
Ru(3)-S(2)
S(1)-C(21)
S(2)-C(22)
S(3)-C(24)
C(1)-C(101)
C(1)-B(4)
C(2)-C(201)
C(2)-B(7)
B(4)-B(8)
B(4)-B(5)
B(5)-B(9)
B(6)-B(11)
B(7)-B(12)
B(7)-B(8)
B(8)-B(9)
B(9)-B(12)
B(10)-B(11)
C(21)-C(22)
C(25)-C(26)
2.163(5)
2.196(6)
2.234(6)
2.365(2)
1.805(6)
1.817(7)
1.812(8)
1.497(7)
1.632(7)
1.488(7)
1.630(8)
1.803(9)
1.823(9)
1.792(9)
1.839(9)
1.809(9)
1.821(9)
1.809(9)
1.750(11)
1.753(10)
1.488(10)
1.419(11)
Ru(3)-C(2)
Ru(3)-B(4)
Ru(3)-S(3)
Ru(3)-S(1)
S(1)-C(26)
S(2)-C(23)
S(3)-C(25)
C(1)-B(5)
C(1)-B(6)
C(2)-B(11)
C(2)-B(6)
B(4)-B(9)
B(5)-B(10)
B(5)-B(6)
B(6)-B(10)
B(7)-B(11)
B(8)-B(12)
B(9)-B(10)
B(10)-B(12)
B(11)-B(12)
C(23)-C(24)
2.175(5)
2.197(6)
2.3607(14)
2.4072(14)
1.813(6)
1.823(7)
1.824(7)
1.610(7)
1.730(8)
1.606(8)
1.741(7)
1.816(9)
1.741(10)
1.822(9)
1.898(9)
1.815(9)
1.807(10)
1.747(11)
1.752(10)
1.776(10)
1.426(10)
Figure 7. Geometrical details (Å and deg) in the faces defined by
Ru(3), C(1), B(6) and C(2) in the closo compound 1 (average of two
crystallographically-independent molecules) and the pseudocloso com-
pound 2.
Previously we observed pseudocloso metal carborane struc-
tures for 1,2-Ph2-3-L-3,1,2-MC2B9 skeletons in which L is an
η-bonded cyclic polyene ligand [M ) Rh, L ) Cp* 3a (Cp* )
η5-C5Me5) and Indy* 3f (Indy* ) η5-C9Me7); M ) Ir, L )
Cp*3e; M ) Ru, L ) η6-C6H6, η6-C6Me6 and η6-C6H4(Me)iPr-
1,43e]. Compound 2 represents the first pseudocloso metal
carborane in which the exopolyhedral ligand is simply σ-bonded
to the M(3) vertex. In keeping with established pseudocloso
metal carboranes the weighted average 11B NMR chemical shift
in 2, +8.18 ppm, lies substantially to high frequency of that in
the otherwise analogous compound 1, -8.34 ppm. By analogy
with the experimentally assigned (Via 11B COSY) spectrum of
1,2-Ph2-3-Indy*-3,1,2-RhC2B9H9,3f the specific 11B NMR reso-
nances of compound 2 are δ 25.5 [B(8)], 18.0 [B(5,11)], 13.2
[B(10)], 4.5 [B(4,7)], 2.0 [B(9,12)] and -17.1 [B(6)] ppm.
C(1)-Ru(3)-C(2)
C(1)-Ru(3)-B(4)
B(4)-Ru(3)-B(8)
S(3)-Ru(3)-S(1)
C(21)-S(1)-C(26) 102.4(4)
C(26)-S(1)-Ru(3) 104.4(2)
C(22)-S(2)-Ru(3) 107.7(2)
C(24)-S(3)-C(25) 103.5(5)
C(25)-S(3)-Ru(3) 107.2(3)
C(21)-C(22)-S(2) 113.1(5)
C(23)-C(24)-S(3) 119.3(6)
C(25)-C(26)-S(1) 119.7(5)
70.5(2)
44.0(2)
48.0(2)
C(2)-Ru(3)-B(7)
B(7)-Ru(3)-B(8)
S(3)-Ru(3)-S(2)
43.8(2)
48.5(2)
84.41(5)
85.74(5) S(2)-Ru(3)-S(1)
85.18(5)
C(21)-S(1)-Ru(3) 104.4(2)
C(22)-S(2)-C(23) 101.3(4)
C(23)-S(2)-Ru(3) 104.1(2)
C(24)-S(3)-Ru(3) 104.3(3)
C(22)-C(21)-S(1) 116.4(5)
C(24)-C(23)-S(2) 118.2(5)
C(26)-C(25)-S(3) 116.7(5)
1
The H NMR spectrum of 2 reveals resonances due to 10
methylene protons betwen 2.9 and 2.1 ppm, with a further, low
frequency, resonance due to 2 protons at 1.12 ppm. We ascribe
the last to the thiamacrocycle H atoms which lie above the cage
phenyl rings. In the 13C{1H} NMR spectrum there are three
equal intensity CH2 resonances between 36.2 and 31.8 ppm,
clearly consistent with the crystallographically determined
structure of 2 and showing unequivocally that the [9]aneS3
ligand is not rapidly rotating about the Ru(3)‚‚‚B(10) axis.
Only three signals (integral-2 doublet, integral-2 apparent
triplet and integral-1 triplet) are observed in the aromatic region
(average of two crystallographically-independent molecules)
with those in compound 2.
Ru-S distances in 2 (one of ca. 2.41 Å, two of ca. 2.36 Å)
are consistently ca. 0.04 Å longer than those in 1, the longest,
Ru(3)-S(1), again being to that sulfur atom which lies ef-
fectively cis to the cage carbon atoms. Both phenyl rings lie
under and reasonably close to an endo-H atom of the [9]aneS3
ligand [C(21)-H‚‚‚C(101-106) plane ) 2.84 Å, C(26)-H‚‚‚C-
(201-206) plane ) 2.97 Å]. Such interligand crowding affords
the thiamacrocycle a conformation with apparent Cs (not C3)
symmetry, having torsion angles of opposite sign about C(25)-
C(26), -29.6(6)°, and C(21)-C(22), 42.6(6)°, and a near-
eclipsed conformation about C(23)-C(24), torsion angle 1.4(6)°.
Note, however, that U(eq) values for C(24) and C(25) are
relatively large; although this suggests partial disorder of these
atoms, we were not able successfully to refine such a disorderd
model.
1
of the H spectrum, and there are only four resonances (1:2:2:
1) between 152.7 and 124.6 ppm in the 13C{1H} spectrum.
Although these patterns could result from coincident resonances
arising from nonrotating phenyl groups (two coincidences in
1
the H spectrum and two in the 13C spectrum), an alternative
explanation is that the phenyl groups in 2 are spinning about
the Ccage-Cphenyl bonds in solution, in spite of the apparent
crowding in Figure 6.

4554 Inorganic Chemistry, Vol. 35, No. 16, 1996
Welch and Weller
Thus the fluxionalities of 1 and 2 in solution appear to be
different in that both polyhedral substituents spin in 1 while
only the phenyl groups apparently spin in 2. On the basis of
the crowding between [9]aneS3 ligand and phenyl groups
revealed (Figure 6) in the crystallographic study of 2 it appears
likely that substantial libration of the macrocycle about the
metal‚‚‚cage axis is necessary to allow the phenyl rings to rotate.
Once again, further study of this system has been frustrated by
the very low solubility of 2 in solvents other than dmso.
fluxional in dmso solution at room temperature, whereas
compound 2 is a pseudocloso metal carborane in which, in dmso
at room temperature, the phenyl rings only appear to be spinning.
These mixed-sandwich compounds presage a large family of
similar species with potentially interesting structural and
spectroscopic properties, and we are currently working to
develop this area of metal carborane chemistry.
Acknowledgment. We thank the EPSRC for support (A.S.W.)
and the Callery Chemical Co. for a generous gift of B10H14.
Conclusions
Supporting Information Available: Tables of anisotropic displace-
ment factors, hydrogen atom coordinates, and interatomic distances and
angles for complexes 1 and 2 (16 pages). Ordering information is given
on any current masthead page.
The first examples of mixed sandwich carborane/thiamacro-
cycle compounds have been synthesised and characterized,
including molecular structure determinations. Compound 1 is
a closo metal carborane with [9]aneS3 substituents that are both
IC9601899