New class of fischer-type carbene complexes containing an o-carboranyl substituent. Synthesis and crystal structure of (CO)5W[C(OMe)(PhC2B10H10)] and (CO)4(PhC2B10H10)

Article abstract of DOI:10.1021/om9707127

Treating lithio-o-carborane RC₂B₁₀H₁₀Li (3a,b R = CH₃, C₆H₅) with metal carbonyl complexes M(CO)₆ (M = Cr, W) followed by quenching the reaction with the electrophilic reagent [M

Full text of DOI:10.1021/om9707127

Organometallics 1998, 17, 1109-1115
1109
New Cla ss of F isch er -Typ e Ca r ben e Com p lexes
Con ta in in g a n o-Ca r bor a n yl Su bstitu en t. Syn th esis a n d
Cr ysta l Str u ctu r e of (CO)5W[C(OMe)(P h C2B10H10)] a n d
(CO)4(P h C2B10H10)Mn [C(OCH3)(CH3)]
Young-J oo Lee, Se-J in Kim, Chang-Hwan Kang, J aejung Ko, and
Sang Ook Kang*
Department of Chemistry, Korea University, Chochiwon, Chung-nam 339-700, Korea
Patrick J . Carroll
Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323
Received August 12, 1997
Treating lithio-o-carborane RC2B10H10Li (3a ,b R ) CH3, C6H5) with metal carbonyl
complexes M(CO)6 (M ) Cr, W) followed by quenching the reaction with the electrophilic
reagent [Me3O]+[BF4]- afforded the [(o-carboranyl)methoxycarbene]metal complexes (CO)5M-
[C(OMe)(RC2B10H10)] (1a -d ) in yields ranging from 37 to 43%. Complexes 1a -d were also
formed on reaction of alkynylcarbene complexes (CO)5M[C(OCH3)(CtCR)] (4a -d : M ) Cr,
W; R ) CH3, C6H5) with B10H12L2 (5; L ) CH3CN) in benzene in 47-63% isolated yield.
The X-ray structure of complex 1d indicates that the tungsten atom is octahedrally
coordinated by (o-carboranyl)methoxycarbene and by five carbonyl groups. Also, the
synthesis of carbene complexes of manganese, bearing an o-carboranyl ligand, has been
studied. Complexes (CO)5Mn(RC2B10H10) (6a ,b: R ) CH3, C6H5) easily react with CH3Li to
give, after methylation of the acyl anion, new (o-carboranyl)metal carbene complexes (CO)4-
(RC2B10H10)Mn[C(OCH3)(CH3)] (2a ,b: R ) CH3, C6H5) in which the two functions are cis.
X-ray analysis of this complex 2b provides support for the assignment of the metal carbene
structure to the o-carborane derivatives.
In tr od u ction
that might potentially stabilize the desired metal car-
bene moiety. Thus, we now report the detailed synthe-
sis and complete characterization of the [(o-carboranyl)-
methoxycarbene]metal complexes 1a -d . Methods for
Although “Fischer-type” carbene complexes have been
extensively studied over the past 30 years,1 many
subclasses of these interesting compounds remain virtu-
ally unexplored. One such subclass, namely [(o-carbo-
ranyl)methoxycarbene]metal complexes, has received
little attention. o-Carborane has attracted some inter-
est due to its ease of preparation and derivatization,
thermal stability, and steric bulk.2 It was therefore of
interest to investigate the possibility of synthesizing
such Fischer carbene complexes using the RC2B10H10
system (RC2B10H10 ) o-carborane). In this respect, we
have started investigating the synthesis of Fischer
carbene complexes bearing a bulky o-carborane unit
(1) For recent reviews reviews see: (a) Hegedus, L. S. Transition
Metals in the Synthesis of Complex Organic Molecules; University
Science Books: Mill Valley, CA, 1994. (b) Wulff, W. D. In Comprehen-
sive Organic Synthesis; Trost, B. M., Fleming, I., Eds.; Pergamon
Press: Oxford, England, 1991; Vol. 5, pp 1065-1113. (c) Schmidt, M.
A.; Miller, J . R.; Hegedus, L. S. J . Organomet. Chem. 1991, 413, 143.
(d) Veillard, A. Chem. Rev. 1991, 91, 743. (e) Rubezhov, A. Z. Russ.
Chem. Rev. (Engl. Transl.) 1991, 60, 89-105. (f) Do¨tz, K. H. New J .
Chem. 1990, 14, 433. (g) Wulff, W. D. In Advances in Metal-Organic
Chemistry; Liebeskind, L. S., Ed.; J AI Press: Greenwich, CT, 1989;
Vol. 1, pp 209-393. (h) Gallop, M. A.; Roper, W. R. Adv. Organomet.
Chem. 1986, 25, 121. (i) Do¨tz, K. H. Angew. Chem., Int. Ed. Engl. 1984,
23, 587. (j) Do¨tz, K. H.; Fischer, H.; Hofmann, P.; Kreissl, F. R.;
Schubert, U.; Weiss, K. Transition Metal Carbene Complexes; Verlag
Chemie: Weinheim, Germany, 1983.
preparing this type of compound 1 are generally based
on (1) addition of a lithio-o-carborane to a metal carbonyl
and (2) two-carbon insertion of an adequate (alkynyl-
carbene)metal fragment into a B10H12L2 system (L )
acetonitrile). This paper also reports the preparation
of new (o-carboranyl)manganese carbene complexes
2a ,b by the nucleophilic reaction of methyllithium with
the corresponding (o-carboranyl)manganese carbonyl
complexes 6a ,b.
(2) Beall, H. In Boron Hydride Chemistry; Muetterties, E., Ed.;
Academic Press: New York, 1975; Chapter 9.
S0276-7333(97)00712-7 CCC: $15.00 © 1998 American Chemical Society
Publication on Web 02/24/1998

1110 Organometallics, Vol. 17, No. 6, 1998
Lee et al.
thermal stability than their alkyl counterparts (i.e. R ) CH3,
C6H5). To the best of our knowledge, this is the first example
in which o-carborane is coordinated with a group VI metal
carbonyl carbene unit, thus improving the stability of the
carbene bond. Prior to our synthesis of complexes 1a -d , the
only report of related [(o-carboranyl)carbene]metal complexes
was (η5-C5H5)(CO)2Re[C(C2B10H11)(C6H5)], synthesized by the
reaction of a cationic carbyne complex of rhenium, [(η5-
C5H5)(CO)2RetC(C6H5)]BBr4, with lithio-o-carborane.7
The synthesis, properties, and the structural studies
of four novel [(o-carboranyl)methoxycarbene]metal com-
plexes 1a -d and new (o-carboranyl)manganese carbene
complexes 2a ,b are reported in this paper.
Resu lts a n d Discu ssion
(CO)5M[C(OMe)(RC2B10H10)] (1: M ) Cr , W; R ) CH3,
C6H6). Each of the [(o-carboranyl)methoxycarbene]metal com-
plexes of type 1 (see reaction 1) was prepared by adaptation
of the general methods currently available (see Experimental
Section).
In an effort to develop a more efficient method for the prep-
aration of [(o-carboranyl)methoxycarbene]metal complexes of
type 1, we have studied the transformation of the carbon-
carbon triple bond in alkynylcarbene molecules into the
o-carborane framework. In alkynylcarbene complexes 4,8 the
carbene moiety is known to be a stronger electron-withdrawing
functional group because of the higher electronegativity of the
oxygen. Conversion of the acetylenic compound to the corre-
sponding o-carborane is generally favored by electron-deficient
alkynes; therefore, we decided to investigate the reactivity of
alkynylcarbene complexes as electron-deficient triple-bond
systems toward B10H12L2 (5: L ) CH3CN)9 (see reaction 2).
This one-pot procedure allows the preparation of a range of
functionalized carbene complexes 1a -d in satisfactory overall
yields (37-43%) based on o-carborane complexes RC2B10H11
(R ) CH3,3 C6H54). Although the process outlined in reaction
1 proved to be quite general, there were, however, structural
limitations (i.e., substituents R ) H) observed for the carbene
complexes 1. For example, several attempts to synthesize the
parent [(o-carboranyl)methoxycarbene]metal complex from the
-
respective anion C2B10H11 were unsuccessful, yielding only
the starting material. The recovery of reagents and thus the
lack of reaction were considered the consequence of the
disproportionation of monolithio-o-carborane, which leads to
the undesired di-C-substituted product.5 This problem was
solved by blocking one of the C-positions in o-carborane with
alkyl groups, effecting the desired reaction at another C site.3
Chromium and tungsten carbene complexes 1a -d are all
moderately air-stable crystalline solids. They are readily
soluble in nonpolar solvents (hexane, benzene) and sparingly
soluble in polar solvents (ether, acetone). All of these com-
plexes are photosensitive, but they show significant thermal
stability in the temperature range 25-80 °C. It was also
observed that the complexes 1a -d exhibited the following
thermal stability trends: M ) W, R ) C6H5 (1d ) > M ) W, R
) CH3 (1c) > M ) Cr, R ) C6H5 (1b) > M ) Cr, R ) CH3 (1a ).
This observation is consistent with similar findings for general
Fischer carbene complexes.6 Moreover, all the [(o-carboranyl)-
methoxycarbene]metal complexes 1a -d exhibited greater
Indeed, compounds 1a -d were produced in high yields (47-
63%) from the direct two-carbon insertion reaction of alkynyl-
carbene complexes 4 with 5. Although this reaction requires
overnight reflux in benzene, its simple reaction path and facile
product isolation make this route attractive.
(CO)4(R C2B10H 10)Mn [C(OCH 3)(CH 3)] (R ) CH 3, C6H 5)
(2). Compound 6a was first prepared by Hawthorne et al.10
Subsequent reaction of complexes 6a ,b with 1.2 mol equiv of
methyllithium gave rise to the corresponding metal acyl
complexes. Further methylation of the acyl anions with CF3-
SO3CH3 produced new (o-carboranyl)metal carbene complexes
2a ,b, as shown in reaction 3. The (o-carboranyl)manganese
carbene complexes 2a ,b are all moderately air-stable crystal-
line solids. They are readily soluble in nonpolar solvents
(7) Chen, J .-B.; Lei, G.-X.; Xu, W.-H.; Zhang, Z.-Y.; Xu, X.-J .; Tang,
Y.-Q. Sci. Sin., Ser. B 1987, 30(1), 24.
(8) (a) Chan, K. S.; Wulff, W. D. J . Am. Chem. Soc. 1986, 108, 5229.
(b) Do¨tz, K. H.; Kuhn, W. J . Organomet. Chem. 1985, 286, C23. (c)
Wulff, W. D.; Yang, D. C. J . Am. Chem. Soc. 1984, 106, 7565.
(9) Cragg, R. H.; Fortuin, M. M.; Greenwood, N. N. J . Chem. Soc. A
1970, 21, 1817.
(3) Gomez, F. A.; Hawthorne, M. F. J . Org. Chem. 1992, 57, 1384.
(4) (a) Garrett, P. M.; Smart, J . C.; Hawthorne, M. F. J . Am. Chem.
Soc. 1969, 91, 4707. (b) Heying, T. L.; Ager, J . W., J r.; Clark, S. L.;
Alexander, R. P.; Papetti, S.; Reid, J . A.; Trotz, S. I. Inorg. Chem. 1963,
2, 1907.
(5) Grimes, R. N. Carborane; Academic Press: New York, 1970.
(6) (a) Reference 1j, p 6. (b) Fischer, E. O.; Leupold, M. Chem. Ber.
1972, 105, 599.
(10) Owen, D. A.; Smart, J . C.; Garrett, P. P.; Hawthorne, M. F. J .
Am. Chem. Soc. 1971, 93, 1362.

Fischer-Type Carbene Complexes
Organometallics, Vol. 17, No. 6, 1998 1111
F igu r e 1. Molecular structure of (CO)5W[C(OMe)-
(PhC2B10H10)] (1d ). The thermal ellipsoids are drawn at
the 30% probability level.
Ta ble 1. Cr ysta llogr a p h ic Da ta for Str u ctu r a l
Stu d ies of Com p ou n d s 1d a n d 2b
(hexane, benzene) and sparingly soluble in polar solvents
(ether, acetone).
formula
fw
WB10C15H18O6
586.25
MnB10C15H21O5
444.37
Sp ectr oscop y. (CO)5M[C(OMe)(RC2B10H10)] (1: M )
Cr , W; R ) CH3, C6H6). The compositions of 1a -d were
established by both elemental analysis and high-resolution
mass spectral analysis. Furthermore, the spectroscopic data
(1H, 13C, and 11B NMR) associated with the [(o-carboranyl)-
methoxycarbene]metal complexes of 1a -d are also consistent
with their assigned structures. The 1H NMR data are likewise
in agreement with the proposed cage structure, confirming the
presence of a methyl resonance (0.74-0.79 ppm) at the cage
2-position and one methoxy resonance (3.87-3.97 ppm) for the
carbene substituent of 1a ,c. The 13C NMR spectra contain
carbene carbon resonances at 363.3 and 337.2 ppm, respec-
cryst class
space group
Z
triclinic
P1h (No. 2)
2
orthorhombic
P212121 (No. 19)
4
cell constants
a, Å
b, Å
9.8455(4)
17.6610(7)
6.7682(2)
1114.69(7)
90.506(3)
107.580(2)
96.023(2)
5.2
15.5537(5)
19.0697(5)
7.4286(3)
2203.4(1)
c, Å
V, Å3
R, deg
â, deg
γ, deg
µ, cm-1
cryst size, mm
6.23
0.40 × 0.20 × 0.15
0.45 × 0.15 × 0.10
1
tively, for 1a ,c. The H NMR spectra confirm the presence of
D
calcd, g/cm3
1.747
1.339
F(000)
radiation
560.00
904.00
a phenyl group showing a cage phenyl multiplet at about 7.5
ppm and one methoxy resonance at about 4.0 ppm for a
carbene group either at the chromium or tungsten metal center
of complexes 1b,d . The 13C NMR spectra contain carbene
carbon resonances at 344.3 and 321.5 ppm, respectively, for
1b,d .
Mo KR (λ ) 0.7170 Å) Mo KR (λ ) 0.7170 Å)
θ range, deg
h, k, l collected
no. of rflns measd
no. of unique rflns
no. of rflns
used in refinement
no. of params
data/param ratio
R1a
2.0-27.0
+11, (21, (8
14 391
2.0-27.0
+19, +24, +9
16 251
4044
4554
3591 (Fo > 3.0σ(Fo2)) 3805 (Fo > 3.0σ(Fo2))
2
2
(CO)4(RC2B10H10)Mn [C(OCH3)(CH3)] (2: R ) CH3, C6H5).
The structures of 2a ,b were easily established through spec-
troscopic (1H, 13C, and 11B NMR) as well as analytical methods.
362
9.9
0.029
0.035
1.308
280
13.59
0.039
0.045
1.702
1
The H and 13C NMR data are likewise in agreement with the
wR2b
GOF
proposed cage structure and confirm the presence of a carbene
C(OCH3)CH3 group at the manganese metal center. The 1H
NMR data contain a methyl resonance (2.04 ppm) for the cage
2-position, a methyl resonance (3.02 ppm), and a methoxy
resonance (4.45 ppm) for the carbene substituents of 2a . The
13C NMR spectrum of 2a contains the carbene carbon reso-
nance at 344.8 ppm. The 1H NMR spectrum of 2b confirms
the presence of a cage phenyl group showing a multiplet of
intensity 5 at about 7.5 ppm, one methoxy resonance at 4.42
ppm, and one methyl resonance at 2.95 ppm. The 13C NMR
spectrum of 2b shows a carbene carbon resonance at 349.2
ppm.
Descr ip tion of th e Molecu la r Str u ctu r e of (CO)5W-
[C(OMe)(P h C2B10H10)] (1d ). The molecular structure and
atom-labeling scheme for complex 1d are shown in Figure 1;
selected bond distances (Å) and angles (deg) are presented in
Table 2. The overall structure of 1d contains an octahedrally
disposed (methoxycarbene)tungsten pentacarbonyl fragment
connected to an o-carboranyl group. The drawing in Figure 1
illustrates how the large o-carborane substituent effectively
shields the carbene ligand from the side. The carbene carbon
atom is coplanar, with a standard deviation of 0.0071 Å, with
the three atoms W, O(26), C(1), and C(13) which surround it,
as expected for such a carbene adduct. The normal to this
a
2
b
R1 ) [∑w(|Fo| - |Fc|)2/∑w|Fo| ]1/2
.
wR2 ) ∑||Fo| - |Fc||/∑|Fo|.
plane almost bisects the directions of the equatorial carbonyl
groups of the tungsten octahedron. Usually, in Fischer-type
carbene complexes, the carbene plane is staggered with repect
to the trans CO-W-CO bonds.11
The W-C(alkoxycarbene) distance (W-C(13), 2.142 (4) Å)
is in the lower range of values generally observed in other
(alkoxycarbene)tungsten structures.12 In this complex, the
carbene carbon atom carries a bulky substituent, which
probably forces the carbene plane to orient in a less favorable
way with respect to the (CO)5M fragment. Notable is the
distortion caused by the metal carbonyl, o-carborane, and
methoxy substituents on the carbene carbon, leading to
deviations from ideal values for the sp2-hybridized carbene
carbon atom. Therefore, the angles around the carbene carbon
decrease in the order W-C(13)-O(26) > W-C(13)-C(1) >
O(26)-C(13)-C(1) (values for 1d are 129.5(3), 126.8(3), and
(11) (a) Mills, O. S.; Redhouse, A. D. J . Chem. Soc. A 1968, 642. (b)
Daran, J . C.; J eannin, Y. Acta Crystallogr., Sect. B: Struct. Crystallogr.
Cryst. Chem. 1980, B36, 1395.

1112 Organometallics, Vol. 17, No. 6, 1998
Lee et al.
Ta ble 2. Selected Bon d Dista n ces (Å) a n d An gles
(d eg) for Com p ou n d 1d
Bond Distances
W-C(13)
2.142(4)
2.045(6)
2.033(6)
1.306(5)
1.141(7)
1.136(7)
1.135(7)
1.545(6)
1.690(6)
1.711(7)
1.729(6)
1.692(6)
1.379(6)
1.389(7)
1.369(8)
W-C(14)
2.042(6)
2.053(6)
2.067(7)
1.447(6)
1.135(7)
1.147(7)
1.802(6)
1.738(6)
1.688(6)
1.503(6)
1.737(6)
1.686(6)
1.372(6)
1.362(8)
1.377(7)
W-C(15)
W-C(16)
W-C(17)
W-C(18)
O(26)-C(13)
O(27)-C(14)
O(29)-C(16)
O(31)-C(18)
C(1)-C(13)
C(1)-B(4)
O(26)-C(19)
O(28)-C(15)
O(30)-C(17)
C(1)-C(2)
C(1)-B(3)
C(1)-B(5)
C(2)-C(20)
C(2)-B(6)
C(2)-B(11)
C(20)-C(25)
C(22)-C(23)
C(24)-C(25)
C(1)-B(6)
C(2)-B(3)
C(2)-B(7)
C(20)-C(21)
C(21)-C(22)
C(23)-C(24)
Bond Angles
C(13)-W-C(14)
C(13)-W-C(16)
C(13)-W-C(18)
C(14)-W-C(16)
C(14)-W-C(18)
C(15)-W-C(17)
C(16)-W-C(17)
C(17)-W-C(18)
C(2)-C(1)-C(13)
W-C(13)-O(26)
O(26)-C(13-C(1)
W-C(15)-O(28)
W-C(17)-O(30)
C(2)-C2(0)-C(21)
96.5(2) C(13)-W-C(15)
94.4(2) C(13)-W-C(17)
91.2(2) C(14)-W-C(15)
169.0(2) C(14)-W-C(17)
88.1(2) C(15)-W-C(16)
87.8(2) C(15)-W-C(18)
91.3(2) C(16)-W-C(18)
177.1(2)
90.0(2)
85.4(2)
89.5(2)
83.7(2)
91.0(2)
90.8(2)
F igu r e 2. Molecular structure of (CO)4(PhC2B10H10)Mn-
[C(OCH3)(CH3)] (2b). The thermal ellipsoids are drawn at
the 30% probability level.
Ta ble 3. Selected Bon d Dista n ces (Å) a n d An gles
d eg) for Com p ou n d 2b
177.5(2) C(13)-O(26)-C(19) 123.8(4)
118.0(3) C(1)-C(2)-C(20)
129.5(3) W-C(13)-C(1)
103.6(3) W-C(14)-O(27)
177.8(6) W-C(16)-O(29)
178.7(5) W-C(18)-O(31)
120.4(4) C(2)-C(20)-C(25)
123.1(3)
126.8(3)
173.8(5)
173.3(5)
177.3(5)
121.1(4)
Bond Distances
Mn(1)-C(1)
Mn(1)-C(16)
Mn(1)-C(18)
O(13)-C(13)
O(16)-C(16)
O(18)-C(18)
C(1)-C(2)
C(13)-C(14)
C(21)-C(26)
C(23)-C(24)
C(25)-C(26)
2.155(3)
1.854(4)
1.837(4)
1.280(4)
1.148(4)
1.145(4)
1.758(4)
1.492(5)
1.381(5)
1.375(7)
1.396(5)
Mn(1)-C(13)
Mn(1)-C(17)
Mn(1)-C(19)
O(13)-C(15)
O(17)-C(17)
O(19)-C(19)
C(2)-C(21)
C(21)-C(22)
C(22)-C(23)
C(24)-C(25)
1.969(3)
1.853(3)
1.817(3)
1.471(4)
1.144(4)
1.143(3)
1.508(4)
1.386(5)
1.402(5)
1.351(8)
C(21)-C(20)-C(25) 118.4(4) C(20)-C(21)-C(22) 119.8(5)
C(21)-C(22)-C(23) 121.0(5) C(22)-C(23)-C(24) 119.2(5)
C(23)-C(24)-C(25) 120.1(5) C(20)-C(25)-C(24) 121.4(5
103.6(3)°, respectively). The methoxy methyl group forms an
angle of 123.8(4)° with the C(13)-O(26) vector and, of the two
possible positions whereby it remains coplanar with the
carbene group, it occupies that cis to the metal. Also, the angle
between the carbene substituents is 103.6(3)°, which is com-
parable with that of 103° for the singlet state of methylene
determined spectroscopically.13 The bond distances and angles
associated with the o-carboranyl group are unexceptional and
are similar to those reported for other structures.14
Descr ip tion of th e Molecu la r Str u ctu r e of (CO)4-
(P h C2B10H10)Mn [C(OCH3)(CH3)] (2b). The conformation
and atomic numbering scheme for 2b are shown in Figure 2;
selected bond distances (Å) and angles (deg) are listed in Table
Bond Angles
C(1)-Mn(1)-C(13)
C(1)-Mn(1)-C(17)
C(1)-Mn(1)-C(19)
C(13)-Mn(1)-C(17) 173.4(1) C(13)-Mn(1)-C(18)
C(13)-Mn(1)-C(19) 85.9(1) C(16)-Mn(1)-C(17)
C(16)-Mn(1)-C(18) 179.3(1) C(16)-Mn(1)-C(19)
C(17)-Mn(1)-C(18)
C(18)-Mn(1)-C(19)
Mn(1)-C(1)-C(2)
90.3(1) C(1)-Mn(1)-C(16)
95.2(1) C(1)-Mn(1)-C(18)
176.2(1) C(13)-Mn(1)-C(16)
89.4(1)
91.3(1)
88.4(1)
91.4(1)
88.1(1)
90.6(1)
88.6(1)
92.1(2) C(17)-Mn(1)-C(19)
88.7(1) C(13)-O(13)-C(15) 125.0(3)
122.9(2) C(1)-C(2)-C(21) 121.5(2)
Mn(1)-C(13)-O(13) 118.5(2) Mn(1)-C(13)-C(14) 125.0(3)
O(13)-C(13)-C(14) 116.3(3) Mn(1)-C(16)-O(16) 174.8(3)
Mn(1)-C(17)-O(17) 170.5(3) Mn(1)-C(18)-O(18) 176.2(3)
(12) (a) Aumann, R.; Fro¨hlich, R.; Zippel, F. Organometallics 1997,
16, 2571. (b) Issberner, K.; Nicke, E.; Wittchow, E.; Do¨tz, K. H.; Nieger,
M. Organometallics 1997, 16, 2370. (c) Aumann, R.; J asper, B.;
Fro¨hlich, R. Organometallics 1995, 14, 3167. (d) Weng, W.; Ramsden,
J . A.; Arif, A. M.; Gladysz, J . A. J . Am. Chem. Soc. 1993, 115, 3824.
(e) Pipoh, R.; Eldik, R. V.; Henkel, G. Organometallics 1993, 12, 2236.
(f) Do¨tz, K. H.; Scha¨fer, T.; Kroll, F.; Harms, K. Angew. Chem., Int.
Ed. Engl. 1992, 31, 1236. (g) Macomber, D. W.; Hung, M.-H.;
Madhukar, P.; Liang, M. Organometallics 1991, 10, 737. (h) Breimair,
J .; Weidmann, T.; Wagner, B.; Beck, W. Chem. Ber. 1991, 124, 2431.
(i) Alvarez, C.; Pacreau, A.; Parlier, A.; Rudler, H.; Daran, J .-C.
Organometallics 1987, 6, 1057. (j) Toledano, C. A.; Parlier, A.; Rudler,
H.; Rudler, M.; Daran, J . C.; Knobler, C.; J eannin, Y. J . Organomet.
Chem. 1987, 328, 357. (k) Parlier, A.; Rudler, M.; Rudler, H.; Daran,
J . C. J . Organomet. Chem. 1987, 323, 353. (l) Butler, I. R.; Cullen, W.
R.; Einstein, F. W. B.; Willis, A. C. Organometallics 1985, 4, 603. (m)
Toledano, C. A.; Parlier, A.; Rudler, H.; Daran, J . C.; J eannin, Y. J .
Chem. Soc., Chem. Commun. 1984, 576. (n) Toledano, C. A.; Rudler,
H.; Daran, J . C.; J eannin, Y. J . Chem. Soc., Chem. Commun. 1984,
547. (o) Toledano, C. A.; Levisalles, J .; Rudler, M.; Rudler, H.; Daran,
J . C.; J eannin, Y. J . Organomet. Chem. 1982, 228, C7. (p) Fischer, E.
O.; Gammel, F. J .; Besenhard, J . O.; Frank, A.; Neugebauer, D. J .
Organomet. Chem. 1980, 191, 261. (q) Casey, C. P.; Polichnowski, S.
W.; Tuinstra, H. E.; Albin, L. D.; Calabrese, J . C. Inorg. Chem. 1978,
17, 3045.
Mn(1)-C(19)-O(19) 179.0(3) C(2)-C(21)-C(22)
119.6(3)
C(2)-C(21)-C(26) 121.0(3) C(22)-C(21)-C(26) 119.3(3)
C(21)-C(22)-C(23) 119.8(4) C(22)-C(23)-C(24) 119.9(5)
C(23)-C(24)-C(25) 120.3(4) C(24)-C(25)-C(26) 120.7(5)
C(21)-C(26)-C(25) 120.0(4)
3. As shown in Figure 2, the structure of complex 2b consists
of a (CO)4(C6H5C2B10H10)Mn unit bonded to a methylmethoxy-
carbene fragment. In this complex, the carbene moiety is
located in a cis arrangement about the Mn(1)-C(1) bond with
respect to the two equatorial carbonyl and two axial carbonyl
groups with C1 symmetry. One of the most significant aspects
of the structure of 2b concerns the disposition of the phenyl
group substituted on the cage. In compound 2b, the cage
carbon is phenyl-substituted and as a result would be expected
to have increased steric repulsion around the metal. Indeed,
the phenyl group substituted on o-carborane is stretched
further away from the carbene ligand in the solid state. Thus,
the steric argument alone would predict the orientation in
Figure 2, with the carbene located away from the phenyl
substituent of the o-carborane ligand. The manganese octa-
hedron is slightly distorted, the principal axes deviating from
linearity as follows: C(13)-Mn(1)-C(17), 173.4(1)°; C(1)-Mn-
(13) Herzberg, G. Proc. R. Soc. London, Ser. A 1961, 262, 291.
(14) Mastryukov, V. S.; Dorofeeva, O. V.; Vilkov, L. V. Russ. Chem.
Rev. (Engl. Transl.) 1980, 49, 1181; Usp. Khim. 1980, 49, 2377.

Fischer-Type Carbene Complexes
Organometallics, Vol. 17, No. 6, 1998 1113
(1)-C(19), 176.2(1)°; C(16)-Mn(1)-C(18), 179.3(1)°. The man-
ganese atom, the atoms of the carbene moiety (C(13), C(14),
O(13)), and the carbon atoms of the three equatorial carbonyls
are essentially coplanar (average deviation from the mean
plane of 0.113 Å with a maximum deviation of 0.380 Å
associated with C(14)). This plane is perpendicular to the Mn-
(1)-C(1) bond (torsional angle{C(1)-Mn(1)-C(13)}-{C(14)-
O(13)-C(13)} ) 103.44°). It has been noted that, due to the
poor π-donation from the (CO)4Mn fragment15 in compound
2b, the Mn(1)-C(13) bond length of 1.969(3) Å is significantly
longer than that found in other manganese-carbene com-
plexes (Cp(CO)(PPh3)MndC(OMe)Et, 1.743(7) (molecule 1) and
1.737(6) Å (molecule 2);16a Cp(CO)2MndC(OEt)Ph, 1.865(14)
Å;16b Cp(CO)2MndCPh2, 1.885(2) Å;16c Cp(CO)2MndC(C{O}-
Ph)Ph, 1.88(2) Å;16d Cp(CO)2MndCMe2, 1.872(10) (molecule 1)
and 1.864(10) Å (molecule 2)16e).
Noticeably, the Mn-C(carbene) distance is even longer than
that found for the analogous bond in the binuclear compound
cis-Mn2(CO)9[C(OCH3)(C6H5)] (1.950 Å).17 The carbene carbon-
oxygen C(13)-O(13) bond length in 2b is 1.280(4) Å and is
shorter than that in the binuclear compound (1.315 Å),
whereas the Mn(1)-C(13)-O(13) angle in the carbene unit of
2b is 118.5(2)°, compared to only 119.4° in the binuclear
compound. The significant shortening of the carbene C(13)-
O(13) bond in compound 2b compared to the analogous bond
in the binuclear compound can be taken as evidence of the
increased π-donating character of the heteroatom (O(13)) in
2b. Therefore, the Mn-C(carbene) distance in complex 6b is
in the upper part of the range of values generally observed in
other manganese carbene complexes. The compound has
adopted the anti conformation about the C(13)-O(13) bond.
The binuclear compound also exhibits a trans geometry about
the carbon-oxygen bond. In addition to being bound to the
o-carborane cage, the manganese is also bonded in an η1-
fashion to four carbonyl groups, which show an average bond
distance of 1.840 Å. Likewise, the bond distances and angles
associated with the o-carboranyl group in 2b are similar to
the structural parameters reported for other organometallic
molecules containing this group.14
tion environments. On the basis of this finding, we
transformed (o-carboranyl)manganese complexes to car-
bene complexes by nucleophilic addition reactions with
methyllithium reagent.
Exp er im en ta l Section
Gen er a l P r oced u r es. All manipulations were performed
under a dry, oxygen-free nitrogen or argon atmosphere using
standard Schlenk techniques or in a Vacuum Atmospheres
HE-493 drybox. THF was freshly distilled over potassium
benzophenone. Ether was dried and distilled from sodium
benzophenone. Dichloromethane and hexane were dried and
distilled over CaH2. 1H, 11B, and 13C NMR spectra were
recorded on a Bruker AM-200 instrument operating at 200.1,
64.2, and 50.3 MHz, respectively. All boron-11 chemical shifts
were referenced to BF3‚O(C2H5)2 (0.0 ppm), with a negative
sign indicating an upfield shift. All proton and carbon
chemical shifts were measured relative to internal residual
benzene from the lock solvent (99.5% C6D6) and then refer-
enced to Me4Si (0.00 ppm). IR spectra were recorded on a
Shimadzu FT-IR-8501 spectrometer. High- and low-resolution
mass spectra were obtained on a VG Micromass 7070H mass
spectrometer. All melting points were uncorrected. Elemental
analyses were obtained from Schwarzkopf Laboratories, Wood-
side, NY. The following starting materials were prepared
4
according to literature procedures: MeC2B10H11,3 PhC2B10H11
,
and Mn(CO)5Br.18 [Me3O]+[BF4]- and CF3SO3CH3 were pur-
chased from Aldrich. Merck silica gel 60 (240-400 mesh) was
used for flash chromatography.
Gen er a l Syn th esis of (CO)5M[C(OMe)(RC2B10H10)] (1:
M ) Cr , W; R ) CH3, C6H6). Meth od A. To a stirred
solution of RC2B10H11 (R ) CH3,3 C6H54) (3.0 mmol) in 30 mL
of diethyl ether, which was cooled to -20 °C, was added 1.6
M n-BuLi (2 mL, 3.2 mmol) via a syringe. The resulting white
suspension was stirred at -20 °C for 2 h and then transferred
through a cannula to a suspension of M(CO)6 (M ) Cr, W) (3.2
mmol) in 80 mL of diethyl ether at 25 °C. After the reaction
mixture was stirred, the solution gradually turned dark brown,
suggesting the formation of a metal acyl complex. The
completion of the reaction was monitored by IR spectroscopy.
The resulting dark brown reaction mixture was stirred at 25
°C for 3 h, and then the solvent was removed under vacuum.
The resulting residue was then taken up in 5 mL of nitrogen-
saturated water. This aqueous solution was cooled to 0 °C,
the electrophilic reagent [Me3O]+[BF4]- (0.85 g, 6.0 mmol, 2
equiv) was added in small portions, and the solution was
stirred for 1 h. The resulting carbene complex was extracted
into methylene chloride, and the combined organic extracts
were washed twice with 25 mL of water and then dried over
anhydrous magnesium sulfate. The solvent was removed
under vacuum, and the resulting residue was taken up in a
minimum of methylene chloride and then transferred to a
column of silica gel. The crude residue was purified by column
chromatography affording >95% pure metal carbene complex
as crystals.
Con clu sion s
This report provides the first detailed report of the
new Fischer-type carbene complexes bearing an o-
carborane substituent. A combination of X-ray crystal-
lographic and spectroscopic studies confirms the nature
of these compounds. The X-ray crystallographic study
of complex 1d , described above, provides the first
structural data for the (o-carboranyl)methoxycarbene
group VI metal complexes. Moreover, all the complexes
1a -d exhibited greater thermal stability than their
alkyl counterparts due to the introduction of an o-
carboranyl group onto the metal carbene unit. Ad-
ditionally, we describe the efficient and selective syn-
thesis of complexes 1 by the following approaches: (1)
using the lithio-o-carborane as a nucleophile and (2)
reacting a carbene complex containing an alkynyl group
with the B10H10(CH3CN)2 system. The o-carborane
system is valuable for the synthesis of a new class of
Fischer-type carbene complexes with different coordina-
An a lytica l Da ta for th e Ch r om iu m a n d Tu n gsten
Car ben e Com plexes 1a-d. (CO)5Cr [C(OMe)(MeC2B10H10)]
(1a ). 1a was prepared from 3.0 mmol of the methyl-o-
carborane MeC2B10H11
. After chromatography on silica gel
with hexane, 1a (0.44 g, 1.1 mmol, 37% yield) was isolated as
a yellow solid. 11B NMR (64.2 MHz, ppm, C6D6): 1.3 (d, B9,
J BH ) 150 Hz), -4.6 (d, B12, J BH ) 200 Hz), -7.9 (d, B8,10, B4,5
,
(15) Do¨tz, K. H.; Bo¨ttcher, D.; J endro, M. Inorg. Chim. Acta 1994,
22, 291.
J BH ) 140 Hz), -9.9 (d, B7,11, B3,6, J BH ) 180 Hz). 1H NMR
(200.13 MHz, ppm, C6D6): 3.97 (s, 3H, OCH3), 0.74 (s, 3H,
CH3). 13C{1H} NMR (50.3 MHz, ppm, C6D6): 363.3 (s, Cr)C),
223.1 (s, CO), 216.9 (s, CO), 67.1 (s, OCH3), 28.4 (s, CH3).
(16) (a) Kelley, C.; Lugan, N.; Terry, M. R.; Geoffroy, G. L.; Haggerty,
B. S.; Rheingold, A. L. J . Am. Chem. Soc. 1992, 114, 6735. (b) Schubert,
U. Organometallics 1982, 1, 1085. (c) Herrmann, W. A.; Hubbard, J .
L.; Bernal, I.; Korp, J . D.; Haymore, B. L.; Hillhouse, G. L. Inorg. Chem.
1984, 23, 2978. (d) Redhouse, A. D. J . Organomet. Chem. 1975, 99,
C29. (e) Friedrich, P.; Besl, G.; Fischer, E. O.; Huttner, G. J .
Organomet. Chem. 1977, 139, C68.
11
12
Exact mass: calcd for
B
C
52Cr1H1616O6 394.1283, found
10 10
(18) Organometallic Syntheses; King, R. B., Ed.; Academic Press:
(17) Huttner, G.; Regler, D. Chem. Ber. 1972, 105, 1230.
New York, 1965; Vol. 1, p 175.

1114 Organometallics, Vol. 17, No. 6, 1998
Lee et al.
394.1296. Anal. Calcd: C, 30.61; H, 4.11. Found: C, 30.75;
H, 4.14. Rf ) 0.88 by silica gel TLC analysis (hexane). Mp )
78 °C. IR spectrum (KBr pellet, cm-1): 2970 (w), 2940 (w),
2880 (w), 2600 (s), 2070 (s), 1985 (s), 1940 (vs), 1460 (w), 1260
(m), 1115 (w), 1040 (w), 950 (w), 920 (w), 870 (w), 850 (w), 830
(w), 800 (w), 730 (w), 690 (w), 670 (m), 660 (m), 630 (w).
(CO)5Cr [C(OMe)(P h C2B10H10)] (1b). 1b was prepared
from 3.0 mmol of the phenyl-o-carborane PhC2B10H11. After
chromatography on silica gel with hexane, 1b (0.48 g, 1.1
mmol, 37% yield) was isolated as a yellow solid. 11B NMR (64.2
MHz, ppm, C6D6): 1.7 (d, B9, J BH ) 150 Hz), -4.5 (d, B12, J BH
carboranyl)methoxycarbene]metal complexes 1a -d , with the
following variations in the procedure of purification. In each
case, the mother liquors were evaporated to dryness, and the
11B and 1H NMR spectra were studied.
(CO)5Cr [C(OMe)(MeC2B10H10)] (1a ). Reaction time: 10
h. Procedure variation: Evaporation of the benzene solution
to dryness and flash chromatography (hexane/CHCl3, 98/2) on
silica; 47% yield (0.53 g, 1.4 mmol).
(CO)5Cr [C(OMe)(P h C2B10H10)] (1b): reaction time, 10 h;
procedure variation, evaporation of the benzene solution to
dryness and flash chromatography (hexane/benzene, 95/5) on
silica; 53% yield (0.71 g, 1.6 mmol).
(CO)5W[C(OMe)(MeC2B10H10)] (1c): reaction time, 12 h;
procedure variation, evaporation of the benzene solution to
dryness and flash chromatography (hexane/CHCl3, 98/2) on
silica; 47% yield (0.75 g, 1.4 mmol).
) 200 Hz), -7.5 (d, B8,10, B4,5, J BH ) 140 Hz), -9.4 (d, B7,11
,
B
3,6, J BH ) 180 Hz). 1H NMR (200.13 MHz, ppm, C6D6): 7.56
(m, 2H, C6H5), 7.39 (m, 3H, C6H5), 3.99 (s, 3H, OCH3). 13C-
{1H} NMR (50.3 MHz, ppm, C6D6): 344.3 (s, CrdC), 205.3 (s,
CO), 198.2 (s, CO), 136.6, 134.2, 130.1 (s, C6H5), 58.6 (s, OCH3).
11
12
Exact mass: calcd for
B
C
52Cr1H1816O6 456.1439, found
10 15
(CO)5W[C(OMe)(P h C2B10H10)] (1d ): reaction time, 12 h;
procedure variation, evaporation of the benzene solution to
dryness and flash chromatography (hexane/benzene, 95/5) on
silica; 63% yield (1.13 g, 1.9 mmol).
456.1428. Anal. Calcd: C, 39.65; H, 3.99. Found: C, 39.58;
H, 3.95. Rf ) 0.66 by silica gel TLC analysis (benzene/hexane,
50/50). Mp ) 84 °C. IR spectrum (KBr pellet, cm-1): 3070
(w), 2970 (w), 2940 (w), 2600 (s), 2080 (s), 1990 (s), 1930 (vs),
1490 (w), 1445 (w), 1385 (w), 1330 (m), 1260 (w), 1220 (w),
1170 (w), 995 (w), 920 (w), 875 (w), 810 (w), 760 (w), 700 (w),
665 (w), 620 (w), 590 (w), 565 (w), 490 (w), 370 (m).
(CO)5W[C(OMe)(MeC2B10H10)] (1c). 1c was prepared
from 3.0 mmol of the methyl-o-carborane MeC2B10H11. After
chromatography on silica gel with hexane, 1c (0.63 g, 1.2
mmol, 40% yield) was isolated as a yellow solid. 11B NMR (64.2
MHz, ppm, C6D6): 1.4 (d, B9, J BH ) 150 Hz), -4.6 (d, B12, J BH
P r ep a r a tion of (CO)5Mn (P h C2B10H10) (6b). A solution
of 6.5 mmol of PhC2B10H10Li (3b) in 80 mL of anhydrous ethyl
ether was slowly added under a nitrogen atmosphere to a
rapidly stirred suspension of 1.76 g (6.4 mmol) of Mn(CO)5Br
in 150 mL of anhydrous ethyl ether. After it was stirred for
2 days at room temperature, the reaction mixture was evapo-
rated to give a dark oil. The oil was dissolved in 50 mL of
benzene, and the resulting solution was rotary-evaporated onto
2 g of predried silica gel. This mixture was placed on a 1 in.
× 6 in. column in hexane, and a yellow band was eluted from
the flash chromatograph with hexane. An additional 100 mL
of eluent was collected. Rotary evaporation of the eluent to
50 mL gave white crystalline needles of complex 6b. A total
of 1.50 g (3.6 mmol, 55%) was collected. Rotary evaporation
to dryness gave 0.30 g of a mixture of the product and Mn2-
(CO)10. The white crystals were sublimed and recrystallized
from hexane. 11B NMR (64.2 MHz, ppm, C6D6): 0.5 (d, B9,
J BH ) 130 Hz), -1.2 (d, B12, J BH ) 160 Hz), -4.2 (d, B8,10, J BH
) 200 Hz), -7.8 (d, B8,10, B4,5, J BH ) 140 Hz), -9.9 (d, B7,11
,
B
3,6, J BH ) 180 Hz). 1H NMR (200.13 MHz, ppm, C6D6): 3.87
(s, 3H, OCH3), 0.79 (s, 3H, CH3). 13C{1H} NMR (50.3 MHz,
ppm, C6D6): 337.2 (s, WdC), 204.1 (s, CO), 197.6 (s, CO), 64.9
(s, OCH3), 27.4 (s, CH3). Exact mass: calcd for
11
12
B
C
184W1H1616O6 526.1387, found 526.1398. Anal. Cal-
10
10
cd: C, 22.91; H, 3.08. Found: C, 22.88; H, 3.04. Rf ) 0.82 by
silica gel TLC analysis (hexane). Mp ) 88 °C. IR spectrum
(KBr pellet, cm-1): 2960 (m), 2870 (m), 2600 (s), 2080 (s), 1980
(s), 1940 (vs), 1470 (m), 1450 (m), 1400 (w), 1370 (w), 1260 (s),
1110 (w), 1055 (w), 1035 (w), 940 (w), 910 (w), 860 (m), 840
(m), 820 (s), 800 (w), 735 (w), 700 (w), 680 (w), 660 (w), 630
(w), 600 (w), 575 (w), 410 (w), 385 (s), 340 (w).
) 100 Hz), -5.3 (d, B4,5, J BH ) 140 Hz), -7.8 (d, B3,6, J BH
)
145 Hz), -9.4 (d, B7, J BH ) 140 Hz), -11.3 (d, B11, J BH ) 145
Hz). 1H NMR (200.13 MHz, ppm, C6D6): 7.74 (d, 2H, C6H5),
11
12
55
7.46 (m, 3H, C6H5). Exact mass: calcd for
B
C
-
13
10
(CO)5W[C(OMe)(P h C2B10H10)] (1d ). 1d was prepared
from 3.0 mmol of the phenyl-o-carborane PhC2B10H11. After
chromatography on silica gel with hexane, 1d (0.76 g, 1.3
mmol, 43% yield) was isolated as a yellow solid. 11B NMR (64.2
MHz, ppm, C6D6): 1.6 (d, B9, J BH ) 150 Hz), -4.4 (d, B12, J BH
Mn1H1516O5 416.1230, found 416.1239. Anal. Calcd: C, 37.69;
H, 3.65. Found: C, 37.88; H, 3.59. Rf ) 0.70 by silica gel TLC
analysis (benzene/hexane, 33/67). Mp ) 88-90 °C. IR spec-
trum (KBr pellet, cm-1): 3090 (w), 3060 (w), 3040 (w), 2580
(s), 2130 (s), 2030 (s), 2000 (s), 1495 (m), 1445 (m), 1075 (m),
1010 (w), 930 (w), 890 (w), 820 (w), 760 (w), 730 (w), 690 (m),
640 (s), 560 (w), 490 (w), 430 (w).
) 200 Hz), -7.3 (d, B8,10, B4,5, J BH ) 140 Hz), -10.2 (d, B7,11
,
B
3,6, J BH ) 180 Hz). 1H NMR (200.13 MHz, ppm, C6D6): 7.54
(m, 2H, C6H5), 7.40 (m, 3H, C6H5), 3.88 (s, 3H, OCH3). 13C-
{1H} NMR (50.3 MHz, ppm, C6D6): 321.5 (s, WdC), 202.5 (s,
CO), 196.1 (s, CO), 133.2, 130.1, 128.6 (s, C6H5), 53.4 (s, OCH3).
Gen er a l P r oced u r e for th e P r ep a r a tion of (CO)4-
(RC2B10H10)Mn [C(OCH3)(CH3)] (2: R ) CH3, C6H5). In a
typical experiment, 1.0 mmol of 6 was dissolved in 25 mL of
THF and the solution cooled to -78 °C. CH3Li (1.0 M, 1.2
mL, 1.2 mmol) was added to the reaction mixture, and the
mixture was stirred for 1 h at -78 °C. The mixture was then
allowed to react at 0 °C for 1 h, and the solution was stirred
for another 2 h at room temperature. The solution gradually
turned dark brown, suggesting the formation of a metal acyl
complex. IR spectra taken at this point confirmed the exclu-
sive formation of the corresponding metal acyl complexes.
Methylation with CF3SO3CH3 (3.0 mmol, 3 equiv) followed by
extraction with hexane gave a yellow solid. Subsequent
separation was performed on the flash column with hexane
to give >95% pure metal carbene complexes 2a ,b as crystals.
(CO)4(MeC2B10H10)Mn [C(OCH3)(CH3)] (2a ). 2a was pre-
pared from 1.0 mmol of 6a . After chromatography on silica
gel with hexane, 0.18 g (0.47 mmol) of 2a was isolated as a
yellow solid. This corresponds to a 47% yield based on the
consumed complex 6a . 11B NMR (64.2 MHz, ppm, C6D6): -1.8
(d, B9, J BH ) 140 Hz), -5.0 (d, B12, J BH ) 145 Hz), -6.8 (d,
11
12
Exact mass: calcd for
B
C
1H1816O6184W 588.1543, found
10 15
588.1539. Anal. Calcd: C, 30.73; H, 3.09. Found: C, 30.69;
H, 3.07. Rf ) 0.79 by silica gel TLC analysis (benzene/hexane,
50/50). Mp ) 92 °C. IR spectrum (KBr pellet, cm-1): 3070
(w), 2970 (w), 2940 (w), 2600 (s), 2080 (s), 1990 (s), 1930 (vs),
1445 (w), 1385 (w), 1330 (m), 1260 (w), 1220 (w), 1170 (w),
995 (w), 920 (w), 810 (w), 760 (w), 700 (w), 590 (w), 565 (w),
490 (w), 370 (m).
Meth od B. In a typical reaction, 3.0 mmol of B10H12(CH3-
CN)2 (5) and 3.2 mmol of alkynylcarbene complexes7 4a -d
9
were mixed in 30 mL of benzene. The mixture was then
allowed to react at 25 °C for 1 h. The solution was stirred for
another 10-12 h at reflux temperature, resulting in the
formation of a dark brown solution. 11B NMR spectra taken
at this point indicated that the starting material had been
completely consumed and that complex 1 was the sole product.
Concentration followed by flash column chromatographic
separation of the resulting reaction mixture gave complex 1.
The same procedure was applied for the rest of the [(o-
B
8,10, B4,5, J BH ) 135 Hz), -7.4 (d, B7,11, B3,6, J BH ) 100 Hz).

Fischer-Type Carbene Complexes
Organometallics, Vol. 17, No. 6, 1998 1115
1H NMR (200.13 MHz, ppm, C6D6): 4.45 (s, 3H, OCH3), 3.02
(s, 3H, CH3), 2.04 (s, 3, CH3). 13C{1H} NMR (50.3 MHz, ppm,
C6D6): 344.8 (s, MndC), 211.8 (s, CO), 64.5 (s, OCH3), 40.3 (s,
an area detector employing graphite-monochromated Mo KR
radiation (λ ) 0.7107 Å) at a temperature of 253 K. X-ray
data for 1d and 2b were processed, and the structure was
solved and refined using the Molecular Structure Corp.’s
Texsan19 package on a Silicon Graphics Indigo R4000 com-
puter. The intensity data were corrected for Lorentz and
polarization effects. Intensities for 1d were corrected for
absorption by applying the program REQAB.20 The structure
was solved by a direct method (SIR8821). Refinement was
carried out by full-matrix least-squares techniques based on
F to minimize the quantity ∑w(|Fo| - |Fc)2 with w ) 1/σ2(F).
Non-hydrogen atoms of 1d and 2b were anisotropically refined,
and hydrogen atoms were isotropically refined. The absolute
configuration of 2b was confirmed by the refinement of the
Flack parameter. The refinement of 1d converged to R1 )
0.029 and wR2 ) 0.035, and that of 2b converged to R1 ) 0.039
and wR2 ) 0.045. Selected bond distances and angles for 1d
and 2b are given in Tables 2 and 3, respectively. The
molecular structures of compounds 1d and 2b are given in
Figures 1 and 2, respectively.
11
12
55
CH3), 28.5 (s, CH3). Exact mass: calcd for
B
C -
10 10
1H19
Mn16O5 384.1543, found 384.1551. Anal. Calcd: C, 31.42; H,
5.01. Found: C, 31.51; H, 5.10. Rf ) 0.70 by silica gel TLC
analysis (benzene). Mp ) 74-76 °C. IR spectrum (KBr pellet,
cm-1): 2960 (w), 2610 (s), 2580 (s), 2550 (s), 2530 (s), 2520 (s),
2080 (s), 2010 (s), 1980 (s), 1460 (m), 1440 (w), 1390 (w), 1300
(s), 1180 (m), 1120 (m), 1090 (w), 1050 (w), 1030 (w), 1000 (m),
950 (w), 810 (w), 740 (w), 660 (s), 650 (s), 470 (m), 430 (w).
(CO)4(P h C2B10H10)Mn [C(OCH3)(CH3)] (2b). 2b was pre-
pared from 1.0 mmol of 6b. After chromatography on silica
gel with hexane, 0.25 g (0.56 mmol) of 2b was isolated as a
yellow solid. This corresponds to a 56% yield based on the
consumed complex 6b. 11B NMR (64.2 MHz, ppm, C6D6): -2.1
(d, B9, J BH ) 100 Hz), -3.4 (d, B12, J BH ) 150 Hz), -6.2 (d,
B
8,10, J BH ) 100 Hz), -7.4 (d, B4,5, B7,11, J BH ) 140 Hz), -9.6
(d, B3,6, J BH ) 160 Hz). 1H NMR (200.13 MHz, ppm, C6D6):
7.70 (d, 2H, C6H5), 7.36 (m, 3H, C6H5), 4.41 (s, 3H, OCH3),
2.95 (s, 3H, CH3). 13C{1H} NMR (50.3 MHz, ppm, C6D6): 349.2
(s, MndC), 212.5 (s, CO), 132.4, 130.4, 128.7 (s, C6H5), 65.9
Ack n ow led gm en t. We appreciate the financial sup-
port of the Korea-USA Cooperative Research Program
by the Korea Science and Engineering Foundation.
11
12
55
(s, OCH3), 42.3 (s, CH3). Exact mass: calcd for
B
C -
1H21
10 15
Mn16O5 446.1700, found 446.1727. Anal. Calcd: C, 40.54; H,
4.76. Found: C, 40.65; H, 4.72. Rf ) 0.76 by silica gel TLC
analysis (benzene). Mp ) 127-128 °C dec. IR spectrum (KBr
pellet, cm-1): 3070 (w), 3040 (w), 2960 (w), 2930 (w), 2600 (s),
2570 (s), 2550 (s), 2080 (s), 2010 (s), 1980 (s), 1500 (w), 1450
(m), 1350 (w), 1300 (s), 1180 (m), 1100 (m), 1070 (m), 1050
(w), 1000 (w), 990 (m), 950 (w), 890 (w), 820 (w), 770 (w), 750
(w), 700 (m), 650 (s), 640 (s), 630 (s), 470 (m), 450 (w), 420 (w).
X-r a y Cr ysta llogr a p h y. Details of the crystal data and a
summary of intensity data collection parameters for 1d and
2b are given in Table 1. The crystals of 1d and 2b were grown
from a hexane solution at -5 °C and were mounted in thin-
walled glass capillaries and sealed under argon. The data sets
of 1d and 2b were collected on a Rigaku diffractometer with
Su p p or tin g In for m a tion Ava ila ble: Tables of bond
distances and angles, atomic coordinates, and thermal param-
eters and ORTEP diagrams for compounds 1d and 2b (18
pages). Ordering information is given on any current mast-
head page.
OM9707127
(19) Texsan: Crystal Structure Analysis Package, Molecular Struc-
ture Coporation Corp., The Woodlands, TX, 1985 and 1992.
(20) REQAB: J acobsen, R. Private communication, 1994.
(21) Burla, M. C.; Camalli, M.; Cascarano, G.; Giacovazzo, C.;
Polidori, G.; Spagna, R.; Viterbo, D. J . Appl. Crystallogr. 1989, 72. 389.