Triamidostannates(II) as sterically demanding ligands for rhodium and iridium

Article abstract of DOI:10.1021/om700960p

Reaction of the triamidostannates(II) MeSi[SiMe₂N(3,5-xyl)] ₃SnLi(OEt₂) (2a) and MeSi[SiMe₂N(p-tol)] ₃SnLi(OEt₂) (2b) with 0.5 molar equiv of [RhCl(COD)] ₂ gave the zwitterionic complexes [MeSi[SiMe₂NAryl] ₂Sn[SiMe₂N(η⁶-Aryl)]Rh(diolefin)] (Aryl = 3,5-xyl: 3a, p-tol: 3b). In these one of the aryl groups acts as a η⁶-ligand, thus resulting in the 18-electron rhodium species. Addition of 1 equiv of PPh₃ to a solution of 3a or 3b yielded the square-planar complexes [MeSi[SiMe₂NAryl]3-SnRh(PPh ₃)(COD)] (Aryl = 3,5-xyl: 4a, p-tol: 4b), in which the stannates are directly bonded to rhodium through Rh-Sn bonds. Treatment of the complexes 4a,b and 5a,b with hydrogen gas in the presence of benzene leads to the hydrogenation of the diolefin and its replacement by benzene as a formal six-electron donor ligand. These 18-electron complexes [MeSi[SiMe₂N(p-tol)] ₃SnRh(PPh₃)(η⁶-arene)] 6a,b and 7a,b are also accessible by reacting the stannates with 0.5 equiv of [RhCl(C ₂H₄)₂]₂, PPh₃, and the appropriate arene. Upon reacting the xylyl stannate 2a with [IrCl(COD)] ₂ and Ph₃P, it was possible to isolate the square-planar Ir complex [MeSi[SiMe₂N(3,5-xyl)]₃SnIr(PPh ₃)(COD)] (8a). In contrast, for the tolyl stannate CH-activation occurred to give the Ir^III compound [MeSi[SiMe₂N(p-tol)] ₂[SiMe₂N(2-C₆H₃-4-CH ₃)]SnIr(H)(PPh₃)(COD)] (8b).

Full text of DOI:10.1021/om700960p

524
Organometallics 2008, 27, 524–533
Triamidostannates(II) as Sterically Demanding Ligands for
Rhodium and Iridium
Michaela Kilian, Hubert Wadepohl, and Lutz H. Gade*
Anorganisch-Chemisches Institut, UniVersität Heidelberg, Im Neuenheimer Feld 270,
69120 Heidelberg, Germany
ReceiVed September 28, 2007
Reaction of the triamidostannates(II) MeSi[SiMe2N(3,5-xyl)]3SnLi(OEt2) (2a) and MeSi[SiMe2N(p-
tol)]3SnLi(OEt2) (2b) with 0.5 molar equiv of [RhCl(COD)]2 gave the zwitterionic complexes
[MeSi[SiMe2NAryl]2Sn[SiMe2N(η6-Aryl)]Rh(diolefin)] (Aryl ) 3,5-xyl: 3a, p-tol: 3b). In these one of
the aryl groups acts as a η6-ligand, thus resulting in the 18-electron rhodium species. Addition of 1 equiv
of PPh3 to a solution of 3a or 3b yielded the square-planar complexes [MeSi[SiMe2NAryl]3-
SnRh(PPh3)(COD)] (Aryl ) 3,5-xyl: 4a, p-tol: 4b), in which the stannates are directly bonded to rhodium
through Rh-Sn bonds. Treatment of the complexes 4a,b and 5a,b with hydrogen gas in the presence of
benzene leads to the hydrogenation of the diolefin and its replacement by benzene as a formal six-
electron donor ligand. These 18-electron complexes [MeSi[SiMe2N(p-tol)]3SnRh(PPh3)(η6-arene)] 6a,b
and 7a,b are also accessible by reacting the stannates with 0.5 equiv of [RhCl(C2H4)2]2, PPh3, and the
appropriate arene. Upon reacting the xylyl stannate 2a with [IrCl(COD)]2 and Ph3P, it was possible to
isolate the square-planar Ir complex [MeSi[SiMe2N(3,5-xyl)]3SnIr(PPh3)(COD)] (8a). In contrast, for
the tolyl stannate CH-activation occurred to give the IrIII compound [MeSi[SiMe2N(p-tol)]2[SiMe2N(2-
C6H3-4-CH3)]SnIr(H)(PPh3)(COD)] (8b).
Ir-Sn complexes16–24 or may be a photocleavable part of M-Sn
Introduction
catalyst precursors.25 Alternatively, they may temporarily bind
Tin(II) halides have found widespread use as cocatalysts in
rhodium- and iridium-catalyzed transformations, in particular,
hydrogenations and carbonylations.1–3 Stannyl fragments may
to the transition metal during the course of a catalytic cycle in
which they act as alkyl or aryl transfer reagents.26
Other than being generated at the transition metal center by
insertion of tin(II) reagents into a metal-X bond, such stannyl
groups may be used as stable preformed trisubstituted stan-
nates(II), which are then coordinated to the transition metal.
This has been the case for the triamidostannates that we
developed using tripodal triamido ligands to generate the
-
effectively act as SnX3 ancillary ligands in Rh-Sn4–15 and
* Corresponding author. Fax: (+49) 6221-545609. E-mail: lutz.gade@
uni-hd.de.
-
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10.1021/om700960p CCC: $40.75
2008 American Chemical Society
Publication on Web 01/19/2008

Triamidostannates(II)
Organometallics, Vol. 27, No. 4, 2008 525
Scheme 1
corresponding molecular cages in which the tin donor atom
occupies an exposed position.27,28
We have begun to study the triamido stannates as monoan-
ionic equivalents of the ER3 ligands of the group 15 elements
and demonstrated their stability in coordination compounds
throughout the d-block.28 Built into the [2,2,2]bicyclooctane cage
generated by tripodal amido ligands, these anionic ligands
possess large cone angles due to the orientation of the N-
substituents. Given the established potential reactivity of their
heavier group 9 metal complexes, a systematic study of their
coordination chemistry to rhodium and iridium has been carried
out.29
Figure 1. Molecular structure of complex 2a. Ellipsoids are drawn
at the 50% probability level. Principal bond lengths (Å) and angles
(deg): N(1)-Li ) 2.052(4), N(2)-Li ) 2.080(4), Sn-N(1) )
2.2296(17), Sn-N(2) ) 2.2204(16), Sn-N(3) ) 2.1292(17);
N(3)-Sn-N(2) ) 102.47(6), N(3)-Sn-N(1) ) 103.28(6),
N(2)-Sn-N(1) ) 82.67(6), Li-N(2)-Sn ) 84.55(11), Li-N(1)-Sn
) 84.97(12).
As will be demonstrated in this work, N-arylated triami-
dostannates serve as supporting ligands for different types of
rhodium 16e and 18e complexes. Provided that potential
cyclometalation of the N-aryl group is suppressed by appropriate
substitutions, they are also suitable for the synthesis of IrI
complexes.
is apparent in the molecular structure of 2a, determined by X-ray
diffraction, which is displayed in Figure 1.
The way the lithium ion coordinates to the triamidostannate
cage in the structure of 2a is similar to that previously
established for the C3 chiral trisilylmethane derivative
HC[SiMe2N{(S)-CH(Me)Ph}]3SnLi(THF).32 The ether-ligated
lithium atom bridges two amido N atoms, N(1) and N(2),
effectively pulling them together [N(1)-Sn-N(2) 82.67(6)°]
and thus widening the angles N(1)-Sn-N(3) (103.28(6)°) and
N(2)-Sn-N(3) (102.47(6)°). The tin atom is partially shielded
by the xylyl substituents in a characteristic “lamp shade”
arrangement.
Synthesis and Structural Characterization of [MeSi-
[SiMe2NAryl]2Sn[SiMe2N(η6-Aryl)]Rh(diolefin)] and their
Conversion to [MeSi[SiMe2NAryl]3SnRh(PPh3)(diolefin)].
Upon reacting MeSi[SiMe2N(3,5-xyl)]3SnLi(OEt2) (2a) and
MeSi[SiMe2N(p-tol)]3SnLi(OEt2) (2b)27c with 0.5 molar equiv
of [RhCl(COD)]2 at -78 °C, the zwitterionic complexes
[MeSi[SiMe2NAryl]2Sn[SiMe2N(η6-Aryl)]Rh(diolefin)] (Aryl )
3,5-xyl: 3a,29 p-tol: 3b) are generated (Scheme 2). Both
complexes are thermally unstable but may be isolated by workup
at -30 °C. 119Sn NMR spectroscopy gave no evidence for a
metal-metal bond between rhodium and tin. For compound 3a
a singlet resonance at –127.8 ppm was detected, the corre-
sponding signal for 3b being observed at -120.0 ppm. The
absence of 119Sn-103Rh coupling and the strong shielding of
the nuclei indicated the nature of the tin as a stannate(II) and
therefore the bonding of the Rh complex fragment to another
site of the ligand. In the case at hand, one of the aryl groups
acts as a η6-ligand, resulting in the 18-electron rhodium species
3a and 3b. The tris(arylamido)stannates (2) may therefore be
seen as adjustable coordinating ligands depending on the
electronic properties of the metal.
Results and Discussion
Synthesis of the N-Arylated Triamidoatannates(II). The
triamine precursors of the tripodal triamidostannates(II) were
synthesized as reported previously by reaction of MeSi-
(SiMe2Cl)330 with 3 equiv of 3,5-dimethylaniline or p-toluidine
and an excess of NEt3 as an auxiliary base to give, respectively,
MeSi[SiMe2NH(3,5-xyl)]3 (1a) and MeSi[SiMe2NH(p-tol)]3
(1b)30 in good yield. Deprotonation of the amines with n-
BuLi and treatment with SnCl2 gave MeSi[SiMe2N(3,5-
xyl)]3SnLi(OEt2) (2a) and MeSi[SiMe2N(p-tol)]3SnLi(OEt2)
(2b)27c as described previously for such triamidostannates
(Scheme 1).31
1
7
The H, 13C, 29Si, Li, and 119Sn NMR spectra of 2a are
consistent with an effective 3-fold symmetry caused by the
fluxional coordination of the ether-ligated lithium atom in
solution. In the solid state this dynamic exchange is frozen, as
(27) (a) Examples: Findeis, B.; Gade, L. H.; Scowen, I. J.; McPartlin,
M. Inorg. Chem. 1997, 36, 960. (b) Contel, M.; Hellmann, K. W.; Gade,
L. H.; Scowen, I.; McPartlin, M.; Laguna, M. Inorg. Chem. 1996, 35, 3713.
(c) Findeis, B.; Contel, M.; Gade, L. H.; Laguna, M.; Gimeno, M. C.;
Scowen, I. J.; McPartlin, M. Inorg. Chem. 1997, 36, 2386. (d) Lutz, M.;
Findeis, B.; Haukka, M.; Pakkanen, T. A.; Gade, L. H. Organometallics
2001, 20, 2505. (e) Lutz, M.; Galka, C. H.; Haukka, M.; Pakkanen, T. A.;
Gade, L. H. Eur. J. Inorg. Chem. 2002, 1968. (f) Lutz, M.; Findeis, B.;
Haukka, M.; Graff, R.; Pakkanen, T. A.; Gade, L. H. Chem.-Eur. J. 2002,
8, 3269. (g) Lutz, M.; Haukka, M.; Pakkanen, T. A.; Gade, L. H.
Organometallics 2002, 21, 3477.
The η6-coordination is indicated by a significant high-field
shift for the coordinated aryl proton (3a: 5.63 and 4.29 ppm;
3b: 5.53 and 4.81 ppm) and carbon NMR resonances (3a: 151.6,
116.3, 95.4, 92.4 ppm; 3b: 150.4, 129.4, 103.0, 93.2 ppm).
(28) Review on triamidostannates: Gade, L. H. Eur. J. Inorg. Chem.
2002, 1257.
(29) Kilian, M.; Wadepohl, H.; Gade, L. H. Organometallics 2007, 26,
3076.
(30) Schubart, M.; Findeis, B.; Gade, L. H.; Li, W.-S.; McPartlin, M.
Chem. Ber. 1995, 128, 329.
(31) (a) Hellmann, K. W.; Steinert, P.; Gade, L. H. Inorg. Chem. 1994,
33, 3859. (b) Hellmann, K. W.; Gade, L. H.; Gevert, O.; Steinert, P.; Lauher,
J. W. Inorg. Chem. 1995, 34, 4069.
(32) Memmler, H.; Kauper, U.; Gade, L. H.; Stalke, D.; Lauher, J. W.
Organometallics 1996, 15, 3637.

526 Organometallics, Vol. 27, No. 4, 2008
Kilian et al.
Scheme 2
Figure 2. Molecular structure of complex 3a. Ellipsoids are drawn
at the 50% probability level. Principal bond lengths (Å) and angles
(deg): N(1)-Sn ) 2.263(4), N(2)-Sn ) 2.160(4), N(3)-Sn )
2.157(5), C(1)-Rh ) 2.458(6), C(2)-Rh ) 2.206(6), C(3)-Rh
) 2.295(6), C(4)-Rh ) 2.300(6), C(5)-Rh ) 2.279(6), C(6)-Rh
) 2.381(6), C(1)-N(1) ) 1.339(7), C(9)-C(10) ) 1.402(8),
C(13)-C(14) ) 1.407(9), C(9)-Rh ) 2.115(6), C(10)-Rh )
2.131(6),C(13)-Rh)2.152(5),C(14)-Rh)2.169(6);N(1)-Sn-N(2)
) 94.64(17), N(1)-Sn-N(3) ) 88.66(17), N(2)-Sn-N(3) )
100.13(18).
Furthermore, the η6-arene carbon signals display coupling to
rhodium or significant broadening.
An X-ray diffraction analysis of 3a indicated the assumption
of the η6-arene coordination in the formally zwitterionic
compounds, and its molecular structure is depicted in Figure 2.
The arrangement of the xylyl groups with respect to the
[2,2,2]bicyclooctane-related stannate cage is quite similar to that
of the lithium stannate (2a). Moreover, the triamido stannate
cage is distorted from an ideal 3-fold symmetry, as is reflected
in the N-Sn-N angles [100.11(18)°, 94.61(17)°, and 88.64(17)°],
and the aromatic ring of the η6-coordinated xylyl group deviates
slightly from planarity. Two carbon-rhodium bonds are shorter
than the others [C(2)-Rh(1) ) 2.208(6) Å, C(5)-Rh(1) )
2.281(6) Å], which is characteristic for the distorted boat
configuration of η6-coordinated aryls.33 Whereas there are
several reports of η6-arene rhodium(I) complexes in the
literature,8,34–36 the complex [Rh(diphos)(η6-PhBPh3)], prepared
by M. Aresta et al.,35 is most closely related. In the latter the
cationic rhodium fragment coordinates to an aryl group that is
part of the negative ion.
These 16-electron complexes can also be directly prepared
by reacting stannates with 0.5 equiv of the rhodium precursor
in the presence of 1 molar equiv of PPh3 at -78 °C. The NBD
derivatives [MeSi[SiMe2NAryl]3SnRh(PPh3)(NBD)] (Aryl )
3,5-xyl: 5a, p-tol: 5b), which tend to be more reactive then their
COD analogues, are accessible by this method (Scheme 2). The
presence of Sn-Rh bonds is again indicated by coupling of tin
with both phosphorus and rhodium (5a: 1JSnRh ) 910 Hz, 2JSnP
) 349 Hz, 5b: 1JSnRh ) 910 Hz, 2JSnP ) 315 Hz) as well as the
low-field shift of the 119Sn NMR signal (5a: -146.4 ppm, 5b:
-147.7 ppm).
An X-ray diffraction study of MeSi[SiMe2N(p-tol)]3-
SnRh(PPh3)(COD) (4b) has established the details of its
molecular structure, which is displayed in Figure 3. The distance
between tin and rhodium is 2.6391(6) Å, which is in the range
of previously characterized Sn-Rh bonds.4–15 Notable is a slight
tilting of the stannate ligand [Si(4)-Sn-Rh ) 167.81°] because
of steric repulsion of PPh3 and two tolyl groups. The detailed
molecular structures of both 5a and 5b have also been
established by X-ray diffraction and are shown in Figures 4
and 5.
The structure of 5a (Figure 4) is very similar to that of 4b
discussed above, the Rh-Sn bond being slightly shorter
[2.6242(5) Å] and the angle Si(4)-Sn-Rh is, at 177.27(2)°,
closer to the ideal linear arrangement than in the COD derivative.
The situation is different in the structure of 5b depicted in Figure
5. The combination of the sterically less demanding NBD and
the N-tolyl stannate leads to a reduced interligand repulsion and
thus greater flexibility in their arrangement. The result is a more
significant tilting of the stannate than in the other derivatives
and thus deviation of the Si(4)-Sn-Rh angle [155.67(3)°] from
linearity as well as a slightly elongated Rh-Sn bond [2.6522(6)
Å].4–15
Synthesis and Structural Charactization of the 18-
Electron Complexes [MeSi[SiMe2N(p-tol)]3SnRh(PPh3)(η6-
arene)]. Treatment of the complexes 4a,b and 5a,b with
hydrogen gas in the presence of benzene leads to the hydroge-
nation of the diolefine and its replacement by benzene as a
Addition of 1 equiv of PPh3 to a solution of the zwitterions
3a and 3b instantaneously converts them to the square-planar
complexes [MeSi[SiMe2NAryl]3SnRh(PPh3)(COD)] (Aryl )
3,5-xyl: 4a, p-tol: 4b), in which the stannate is directly bonded
to rhodium through Rh-Sn bonds. This is indicated by the
observation of 119Sn-103Rh and 119Sn-31P coupling in the 119Sn
2
NMR spectra (1JSnRh ) 802 Hz, JSnP ) 349 Hz for 4a and
2
1JSnRh ) 806 Hz, JSnP ) 311 Hz for 4b) as well as the
coordination shift of the 119Sn NMR resonances to higher field
(4a: -176.0 ppm, 4b: -176.5 ppm).
(33) Muetterties, E. L.;. Bleeke, J. R.; Wucherer, E. J.; Albright, T. A.
Chem. ReV. 1982, 82, 499.
(34) (a) Uson, R.; Oro, L. A.; Foces-Foces, C.; Cano, F. H.; Vegas, A.;
Valderrama, M. J. Organomet. Chem. 1981, 215, 241. (b) Uson, R.; Oro,
L. A.; Foces-Foces, C.; Cano, F. H.; Garcia-Blanco, S.; Valderrama, M. J.
Organomet. Chem. 1982, 229, 293. (c) Singewald, E. T.; Mirkin, C. A.;
Levy, A. D.; Stern, C. L. Angew. Chem. 1994. 106, 2524; Angew. Chem.,
Int. Ed. 1994, 33, 2473. (d) Singewald, E. T.; Slone, C. S.; Stern, C. L.;
Mirkin, C. A.; Yap, G. P. A.; Liable-Sands, L. M.; Rheingold, A. L. J. Am.
Chem. Soc. 1997, 119, 3048. (e) Werner, H.; Canepa, G.; Ilg, K.; Wolf, J.
Organometallics 2000, 19, 4756. (f) Canepa, G.; Brandt, C. D.; Ilg, K.;
Wolf, J.; Werner, H. Chem.-Eur. J. 2003, 9, 2502.
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2032.
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F. H.; Garcia-Blanco, S. Inorg. Chim. Acta 1980, 42, 75.

Triamidostannates(II)
Organometallics, Vol. 27, No. 4, 2008 527
Figure 3. Molecular structure of complex 4b. Ellipsoids are drawn
at the 50% probability level. Principal bond lengths (Å) and angles
(deg): Rh-Sn ) 2.6391(6), P-Rh ) 2.3296(14), N(1)-Sn )
2.129(4), N(2)-Sn ) 2.120(4), N(3)-Sn ) 2.121(4), C(1)-C(2)
) 1.378(8), C(5)-C(6) ) 1.367(8), C(1)-Rh ) 2.183(5), C(2)-Rh
) 2.208(6), C(5)-Rh ) 2.208(5), C(6)-Rh ) 2.226(5); P-Rh-Sn
) 93.89(4), N(1)-Sn-N(2) ) 95.78(16), N(1)-Sn-N(3) )
108.25(16),N(2)-Sn-N(3))97.85(17),N(1)-Sn-Rh)108.62(12),
N(2)-Sn-Rh)119.60(12),N(3)-Sn-Rh)123.07(12),Si(4)-Sn-Rh
) 167.81(3).
Figure 5. Molecular structure of complex 5b. Ellipsoids are drawn
at the 50% probability level. Principal bond lengths (Å) and angles
(deg): Rh-Sn ) 2.6522(6), P-Rh ) 2.3237(16), N(1)-Sn )
2.117(5), N(2)-Sn ) 2.139(5), N(3)-Sn ) 2.092(5), C(1)-C(2)
) 1.390(9), C(4)-C(5) ) 1.377(9), C(1)-Rh ) 2.190(6), C(2)-Rh
) 2.192(6), C(4)-Rh ) 2.177(6), C(5)-Rh ) 2.196(6); P-Rh-Sn
) 102.67(4), N(1)-Sn-N(2) ) 95.83(18), N(3)-Sn-N(1) )
99.74(18),N(3)-Sn-N(2))100.03(18),N(1)-Sn-Rh)133.62(13),
N(2)-Sn-Rh)97.98(13),N(3)-Sn-Rh)120.84(13),Si(4)-Sn-Rh
) 155.67(3).
Scheme 3
Figure 4. Molecular structure of complex 5a. Ellipsoids are drawn
at the 50% probability level. Principal bond lengths (Å) and angles
(deg): Rh-Sn ) 2.6242(5), P-Rh ) 2.3279(11), N(1)-Sn )
2.113(3), N(2)-Sn ) 2.117(3), N(3)-Sn ) 2.125(3), C(1)-C(2)
) 1.391(7), C(4)-C(5) ) 1.365(6), C(1)-Rh ) 2.206(4), C(2)-Rh
) 2.160(4), C(4)-Rh ) 2.186(4), C(5)-Rh ) 2.212(4); P-Rh-Sn
) 97.43(3), N(1)-Sn-N(2) ) 99.25(13), N(1)-Sn-N(3) )
103.73(13), N(2)-Sn-N(3) ) 97.08(13), N(1)-Sn-Rh ) 113.11(9),
N(2)-Sn-Rh)118.45(10),N(3)-Sn-Rh)121.72(9),Si(4)-Sn-Rh
) 177.27(2).
(144–159 Hz), a feature that has been previously observed for
18e Rh half-sandwich complexes.34–36
The structural details of the η6-benzene derivative 6b have
been established by X-ray diffraction, and its molecular structure
is displayed in Figure 6. Similar to other examples previously
in the literature,36 the π-coordinated benzene ligand has lost its
planarity and adopts a “boat conformation” with two short
[C(1)-Rh ) 2.266(3), C(4)-Rh ) 2.252(3) Å] and four long
[C(2)-Rh ) 2.312(3), C(3)-Rh ) 2.316(3), C(5)-Rh )
2.320(3), C(6)-Rh ) 2.333(3) Å] Rh-C distances. The
rhodium-tin distance is 2.5833(5) Å and thus shorter than in
4b, 5a, and 5b, while being close to that of the first neutral
η6-arene-Rh(I)-Sn complex [Rh(η6-C6H5Me)(C8H14){SnCl-
(N(SiMe3)2)2}] reported by Lappert et al. [Rh-Sn 2.554(1) Å].8
Cyclometalation of the Stannate or Not? Synthesis and
Structural Characterization of Ir-Sn Complexes. The syn-
thesis of the iridium analogues of the rhodium diolefin com-
plexes was carried out by a similar procedure by reacting
formal six-electron donor ligand (Scheme 3). Such aryl com-
plexes are also accessible by reacting the stannates 2a and 2b
with 0.5 equiv of [RhCl(C2H4)2]2, PPh3, and the appropriate
arene. It is assumed that the ethylene complexes [MeSi-
[SiMe2N(aryl)]3SnRh(PPh3)(C2H4)2] are formed in the first
instance; however, they are probably too labile to be isolated
or even detected by NMR spectroscopy. In all cases, the 18-
electron complexes [MeSi[SiMe2N(p-tol)]3SnRh(PPh3)(η6-
arene)] 6a,b and 7a,b were obtained (Scheme 3). The latter are
characterized by large 103Rh-31P coupling constants (214–215
Hz) compared to those for the square-planar compounds

528 Organometallics, Vol. 27, No. 4, 2008
Kilian et al.
Figure 6. Molecular structure of complex 6b. Ellipsoids are drawn
at the 50% probability level. Principal bond lengths (Å) and angles
(deg): Rh-Sn ) 2.5833(5), P-Rh ) 2.2429(9), N(1)-Sn )
2.139(3), N(2)-Sn ) 2.115(2), N(3)-Sn ) 2.096(2), C(1)-Rh )
2.266(3), C(2)-Rh ) 2.312(3), C(3)-Rh ) 2.316(3), C(4)-Rh
) 2.252(3), C(5)-Rh ) 2.320(3), C(6)-Rh ) 2.333(3); P-Rh-Sn
) 100.46(3), N(1)-Sn-N(2) ) 96.23(10), N(1)-Sn-N(3) )
97.20(10), N(2)-Sn-N(3) ) 99.97(10), N(1)-Sn-Rh ) 111.37(7),
N(2)-Sn-Rh)115.13(7),N(3)-Sn-Rh)130.65(7),Si(4)-Sn-Rh
) 167.45(2).
Figure 7. Molecular structure of complex 8b. Ellipsoids are drawn
at the 50% probability level. Principal bond lengths (Å) and angles
(deg): Ir-Sn ) 2.5798(8), Ir-P ) 2.3599(11), Ir-H(99) 1.56(6),
N(1)-Sn ) 2.074(3), N(2)-Sn ) 2.079(3), N(3)-Sn ) 2.080(3),
C(1)-C(2) ) 1.403(5), C(5)-C(6) ) 1.385(5), C(1)-Ir ) 2.237(3),
C(2)-Ir ) 2.228(3), C(5)-Ir ) 2.271(3), C(6)-Ir ) 2.286(3),
C(10)-N(1) ) 1.423(4), C(11)-Ir ) 2.145(3); P-Ir-Sn )
126.87(3), C(11)-Ir-P ) 86.26(9), C(11)-Ir-Sn ) 79.07(9),
N(1)-Sn-N(2) ) 103.30(12), N(1)-Sn-N(3) ) 105.88(12),
N(2)-Sn-N(3) ) 98.74(12), N(1)-Sn-Ir ) 97.71(8), N(2)-Sn-Ir
) 132.82(8), N(3)-Sn-Ir ) 115.42(8), Si(4)-Sn-Ir ) 159.42(2).
Scheme 4
broad and for the ortho-carbon atom at 130.1 ppm coupling to
phosphorus is observed (2JPC ) 9.2 Hz). These spectroscopic
features are very similar to those reported for cis-(P,P)-
[IrH(PBz3)(COD){(C6H4CH2)PBz2}]PF6.37 The presence of an
iridium-tin bond is confirmed by the 119Sn-31P coupling (2JSnP
) 1713 Hz), which has been observed in the 31P and 119Sn
NMR spectra of compound 8b.
The coordination geometry at the iridium center of 8b has
been established by X-ray diffraction as (highly) distorted
octahedral (Figure 7). The Ir-Sn bond length of 2.5798(8) Å
lies in the expected range.10–24 The deviation of the rectangular
ligand disposition is most pronounced for the Sn-Ir-P angle,
which is 126.87(3)°. The iridium atom, the COD, and the
hydride as well as C(11) adopt an arrangement that is close to
planar. Since the stannate unit is bent toward the cyclometalated
part [which is reflected in a Si(4)-Sn-Ir angle of 159.42(2)°],
the two remaining tolyl groups point away from the iridium
center to make room for COD.
The Ir-H(99) bond length [1.56(6) Å] falls within the range
of that in other iridium complexes with terminal hydride ligands
[mean 1.573(8) Å of 360 observations currently in the Cam-
bridge Crystallographic Database].
Conclusions
This study has established the use of the tripodal triamido
stannates(II) as very bulky ligands for the heavier group 9
metals. While their aryl periphery may act as an initial binding
site for rhodium, they remain stable in the subsequent trans-
formations at this metal. Coordination to iridium may occur with
concomitant cyclometalation, a reaction that is avoided by
introduction of suitably placed substituents in the peripheral aryl
groups as in the 3,5-xylyl unit in compound 8a. To which extent
the stannates with [IrCl(COD)]2 and Ph3P. In the case of xylyl
stannate 2a it was possible to isolate the square-planar Ir
complex [MeSi[SiMe2N(3,5-xyl)]3SnIr(PPh3)(COD)] (8a),
whereas for the N-tolyl-substituted stannate this product
was not formed, but CH-activation occurred to give the
IrIII compound [MeSi[SiMe2N(p-tol)]2[SiMe2N(2-C6H3-4-
CH3)]SnIr(H)(PPh3)(COD)] (8b) (Scheme 4).
The resulting hydride in 8b is detected at -12.23 ppm in the
proton NMR spectrum as a doublet (2JPH ) 24 Hz) associated
with the tin satellites (2JSnH ) 131 Hz). In the 13C NMR
spectrum the signals of the ortho-metalated tolyl substituent are
(37) Landaeta, V. R.; Peruzzini, M.; Herrera, V.; Bianchini, C.; Sanchez-
Delgado, R. A.; Goeta, A. E.; Zanobini, F. J. Organomet. Chem. 2006,
691, 1039.

Triamidostannates(II)
Organometallics, Vol. 27, No. 4, 2008 529
disk): 3021 (w), 2950 (w), 2917 (w), 1599 (s), 1479 (w, br), 1352
(m), 1246 (m), 1179 (m), 1048 (w), 958 (w), 844 (m), 825 (s), 722
(m), 689 (w), 654 (w) cm-1. 1H NMR (399.9 MHz, C6D6): δ 6.91
(s, 6H, 2,6-Hxyl), 6.60 (s, 3H, 4-Hxyl), 3.03 (q, 3JHH ) 7.1 Hz, 8H,
the triamido stannates(II) tolerate other transformations is
currently being studied and will determine their usefulness as
ancillary ligands for the late transition metals.
3
O(CH2CH3)2), 2.22 (s, 18H, C6H3(CH3)2), 0.67 (t, JHH ) 7.1 Hz,
Experimental Section
12H, O(CH2CH3)2), 0.58 (s, 18H, Si(CH3)2), 0.27 (s, 3H, SiCH3).
7Li NMR (155.4 MHz, C6D6): δ -1.14 (s). 13C NMR (100.6 MHz,
C6D6): δ ) 153.3 (s, 1-Cxyl), 138.2 (s, 3,5-Cxyl), 126.0 (s, 4-Cxyl),
123.4 (s, 2,6-Cxyl), 66.0 (s, O(CH2CH3)2), 21.6 (s, C6H3(CH3)2),
14.1 (s, O(CH2CH3)2), 4.3 (s, Si(CH3)2), –14.5 (s, SiCH3). 29Si NMR
(79.4 MHz, C6D6): δ –2.5 (s, SiMe2), -96.4 (s, SiMe). 119Sn-NMR
General Experimental Procedures. All manipulations were
performed under an inert gas atmosphere of dried argon (desiccant
P4O10, Granusic, J.T. Baker) in standard (Schlenk) glassware or
by working in a glovebox. All reaction flasks were heated prior to
use by way of three evacuation-refill cycles. Solvents and solutions
were transferred by canula-septa techniques. Solvents were dried
according to standard methods, saturated with argon, and stored
over potassium mirrors. MeSi(SiMe2Cl)3,30 [RhCl(COD)]2,38
[RhCl(NBD)]2,39 [RhCl(C2H4)2]2,40 and [IrCl(COD)]241 were syn-
thesized according to literature procedures. The rhodium and iridium
precursors were dried over MgSO4 as solutions in dichloromethane
and subsequently precipitated by adding hexane. All other reagents
(149.1 MHz, C6D6):
δ ) -108.7 (s). Anal. Calcd for
C35H58LiN3OSi4Sn (774.8): C, 54.25; H, 7.54; N, 5.42. Found: C,
54.46; H, 7.84; N, 5.45.
[MeSi[SiMe2N(3,5-xyl)]2Sn[SiMe2N(η6-3,5-xyl)]Rh(COD)] (3a).
300 mg (0.39 mmol) sample of MeSi[SiMe2N(3,5-
A
xyl)]3SnLi(OEt2) (2a) and 95 mg (0.19 mmol) [RhCl(COD)]2 were
suspended in precooled toluene at -78 °C. The orange suspension
was stirred for 30 min in the cold before it was warmed to room
temperature and centrifuged. Then the centrifugate was concentrated
in vacuo and stored at -30 °C to precipitate 3a as a yellow solid
(304 mg, 87%). It was possible to obtain single crystals suitable
for X-ray diffraction analysis at -30 °C out of a concentrated
solution in toluene. FT-IR (KBr-disk): 3019 (w), 2940 (w), 2884
(w), 1597 (m), 1581 (m), 1532 (w), 1505 (m), 1459 (m), 1345 (s),
1301 (s), 1238 (m), 1195 (w), 1173 (m), 1159 (m), 1037 (w) 961
1
7
were commercially available and used as received. H, Li, 13C,
29Si, 31P, and 119Sn NMR spectra were recorded on a Bruker DRX
200, Avance II 400, or Avance III 600. NMR spectra are quoted
7
in ppm relative to tetramethylsilane (1H and 13C); Li, 29Si, 31P,
and 119Sn NMR data are listed in ppm relative to an external
standard [7Li: LiClaq, 29Si: Si(CH3)4, 31P: 85% H3PO4, and 119Sn:
Sn(CH3)4]. 1H and 13C NMR spectra were referenced internally
using the residual protonated solvent peak (1H) or the carbon
resonance (13C). Infrared spectra were recorded on a Varian 3100
FT-IR spectrometer. Elemental analyses were carried out in the
microanalytical laboratory of the chemistry department of Heidelberg.
Preparation of the Compounds. MeSi[SiMe2NH(3,5-xyl)]3
(1). To a solution of 8.11 mL (64.9 mmol) of 3,5-dimethylaniline
and NEt3 (10.1 mL) in Et2O (60 mL) was added slowly at 0 °C a
solution of 7.01 g (21.6 mmol) of MeSi(SiMe2Cl)3 in Et2O (70
mL). The suspension was warmed to room temperature within 18 h.
Then the solvent was removed in vacuo and the residue was
suspended in pentane. It was filtered and the solid was washed three
times with pentane. The filtrate was concentrated under reduced
pressure to about 20 mL and stored at -80 °C. Compound 1 was
obtained as an off-white solid (10.97 g, 88%). FT-IR (KBr-disk):
3368 (m, br), 3022 (m), 2952 (s), 2918 (m), 2895 (m), 1597 (s),
1479 (m), 1329 (m), 1250 (s), 1176 (m), 1031 (s, br), 828 (s, br),
770 (s, br), 687 (m), 651 (m) cm-1. 1H NMR (399.9 MHz, C6D6):
δ 6.42 (s, 3H, 4-Hxyl), 6.26 (s, 6H, 2,6-Hxyl), 3.32 (s, 3H, N H),
2.18 (s, 18H, C6H3(C H3)2), 0.49 (s, 3H, SiC H3), 0.42 (s, 18H,
Si(CH3)2). 13C NMR (100.6 MHz, C6D6): δ 147.6 (s, 1-Cxyl), 138.8
(s, 3,5-Cxyl), 120.5 (s, 4-Cxyl), 115.1 (s, 2,6-Cxyl), 21.6 (s,
C6H3(CH3)2), 1.7 (s, Si(CH3)2), -9.8 (s, SiCH3). 29Si NMR (79.4
MHz, C6D6): δ –2.1 (s, SiMe2), -88.2 (s, SiMe). Anal. Calcd for
C31H51N3Si4 (578.1): C, 64.41; H, 8.89; N, 7.27. Found: C, 63.85;
H, 8.93; N, 7.41.
(w), 874 (m), 852 (m), 827 (m), 775 (m), 703 (w), 640 (m) cm-1
.
1H NMR (399.9 MHz, C6D6): δ 7.04 (s, 4H, 2,6-Hxyl), 6.58 (s, 2H,
4-Hxyl), 5.63 (s, 2H, 2,6-Hη6-xyl), 4.29 (s, 1H, 4-H η6-xyl), 3.62 (s,
br, 4H, CHCOD), 2.30 (s, 12H, C6H3(CH3)2), 2.06–1.96 (m, 4H, CH2
COD), 1.68–1.58 (m, 4H, CH2 COD), 1.23 (s, 6H, η6-C6H3(CH3)2),
0.85 (s, 6H, Si(CH3)2), 0.67 (s, 6H, Si(CH3)2), 0.65 (s, 6H,
Si(CH3)2), 0.37 (s, 3H, SiCH3). 13C NMR (100.6 MHz, C6D6): δ
155.4 (s, 1-Cxyl), 151.6 (s, br, 1-C η6-xyl), 137.8 (s, 3,5-Cxyl), 123.6
1
(s, 2,6-Cxyl), 121.2 (s, 4-Cxyl), 116.3 (d, J(103Rh-13C) ) 3.4 Hz,
3,5-C η6-xyl), 95.4 (s, br, 2,6-C η6-xyl), 92.4 (d, 1J(103Rh-13C) ) 3.3
Hz, 4-C η6-xyl), 77.6 (d, 1J(103Rh-13C) ) 13.0 Hz, CHCOD), 31.8 (s,
CH2 COD), 21.9 (s, C6H3(CH3)2), 18.7 (s, η6-C6H3(CH3)2), 4.4 (s,
Si(CH3)2), 4.1 (s, Si(CH3)2), 3.3 (s, Si(CH3)2), -13.5 (s, SiCH3).
29Si NMR (79.4 MHz, C6D6): δ -0.8 (s, SiMe2), -7.1 (s, SiMe2),
-85.2 (s, SiMe). 119Sn NMR (149.1 MHz, C6D6): δ -127.8 (s).
Anal. Calcd for C39H60N3RhSi4Sn (904.9): C, 51.77; H, 6.68; N,
4.64. Found: C, 51.23; H, 6.99; N, 4.91.
[MeSi[SiMe2N(p-tol)]2[SiMe2N(η6-p-tol)]SnRh(COD)] (3b). A
200 mg (0.27 mmol) portion of MeSi[SiMe
2N(p-tol)]3SnLi(OEt2)
(2b) and 67 mg (0.14 mmol) of [RhCl(COD)]2 were suspended in
precooled toluene at -78 °C. The orange suspension was stirred
for 60 min in the cold before it was centrifuged. Then the
centrifugate was concentrated in vacuo and stored at –30 °C to
precipitate 3b as a yellow solid (95 mg, 40%). FT-IR (KBr-disk):
3009 (w), 2944 (w), 2883 (w), 1603 (w), 1550 (w), 1497 (s), 1332
(m), 1247 (s), 1107 (w), 1031 (w), 917 (m), 809 (s), 778 (s), 677
(m), 508 (m) cm-1. 1H NMR (600.1 MHz, C6D6): δ 7.25 (d, 3JHH
MeSi[SiMe2N(3,5-xyl)]3SnLi(OEt2) (2a). A 1.996 g (3.45 mmol)
amount of MeSi[SiMe2NH(3,5-xyl)]3 (1) was dissolved in Et2O and
cooled to –78 °C. A 2.5 M solution of n-BuLi (4.5 mL, 11.25 mmol)
was added. After 2 h at room temperature it was cooled again to
-78 °C and the yellow solution was transferred onto 655 mg (3.45
mmol) of solid SnCl2. The orange suspension was allowed to warm
to room temperature and stirred for 18 h. After removal of the
solvent in vacuo the red residue was extracted three times with
hexane. The combined extracts were concentrated in vacuo to about
10 mL, and storing at –80 °C yielded a pale yellow solid that was
washed three times with hexane (1.086 g, 41% yield). FT-IR (KBr-
3
) 8.2 Hz, 4H, tol), 7.10 – 7.00 (m, 4H, tol), 5.53 (d, JHH ) 7.2
3
Hz, 2H, η6-tol), 4.81 (d, JHH ) 7.3 Hz, 2H, η6-tol), 3.59 (s, br,
4H, CHCOD), 2.25 (s, 6H, C6H4CH3), 2.06 – 1.96 (m, 4H, CH2 COD),
1.72 – 1.56 (m, 4H, CH2 COD), 1.12 (s, 3H, η6-C6H4CH3), 0.78 (s,
6H, Si(CH3)2), 0.62 (s, 6H, Si(CH3)2), 0.58 (s, 6H, Si(CH3)2), 0.35
(s, 3H, SiCH3). 13C NMR (150.9 MHz, C6D6): δ 152.7 (s, C1tol),
150.4 (s, br, C1η6-tol), 129.6 (s, C3,5 tol), 129.4 (d, 1J(103Rh-13C) )
4.4 Hz, C3,5 η6-tol), 127.2 (s, C4tol), 125.4 (s, C2,6tol), 103.0 (d,
1J(103Rh-13C) ) 4.4 Hz, C2,6 η6-tol), 93.2 (s, br, C4 η6-tol),
78.4 (d, 1J(103Rh-13C) ) 12.8 Hz, CHCOD), 31.9 (s, CH2 COD), 20.8
(s, C6H3CH3), 17.4 (s, η6-C6H3CH3), 4.1 (s, Si(CH3)2), 3.8 (s,
Si(CH3)2), 2.9 (s, Si(CH3)2), -13.8 (s, SiCH3). 29Si NMR (39.7
MHz, C6D6): δ -1.2 (s, SiMe2), -7.2 (s, SiMe2), -85.4 (s, SiMe).
119Sn NMR (74.6 MHz, C6D6): δ -120.0 (s). Anal. Calcd for
(38) Giordano, G.; Crabtree, R. H. Inorg. Synth. 1990, 28, 88.
(39) Abel, E. W.; Bennett, M. A.; Wilkinson, G. J. Chem. Soc. 1959,
3178.
(40) Cramer, R. Inorg. Synth. 1990, 28, 86.
(41) Herde, J. L.; Lambert, J. C.; Senoff, C. V. Inorg. Synth. 1974, 15,
18.

530 Organometallics, Vol. 27, No. 4, 2008
Kilian et al.
C36H54N3RhSi4Sn (862.8): C, 50.11; H, 6.31; N, 4.87. Found: C,
49.34; H, 6.41; N, 4.66.
was isolated as a bright orange microcrystalline solid in 83% (248
mg) yield. The product could be crystallized from a solution in
toluene at -30 °C. FT-IR (KBr-disk): 3002 (w), 2942 (w), 2858
(w), 1596 (m), 1581 (s), 1477 (w), 1434 (m), 1351 (w), 1298 (s),
1239 (m), 1157 (m), 1091 (w), 1036 (m), 961 (m), 890 (m), 856
(s), 828 (s), 779 (m), 747 (m), 699 (s), 646 (m), 509 (m) cm-1. 1H
NMR (399.9 MHz, C6D6): δ 7.41–7.34 (m, 8H, PPh3), 7.07–6.97
(m, 25H, PPh3), 6.96 (s, 6H, 2,6-Hxyl), 6.60 (s, 3H, 4-Hxyl),
5.35–4.85 (m, 2H, 2/3/5/6-NBD CH), 3.16 (s, br, 2H, 1/4-NBD
CH), 3.02–2.66 (m, 2H, 2/3/5/6-NBD CH), 2.29 (s, 18H,
C6H3(CH3)2), 1.42 – 1.26 (m, 2H, CH2 NBD), 0.62 (s, 18H, Si(CH3)2),
0.28 (s, 3H, SiCH3). 13C NMR (150.9 MHz, C6D6): δ 155.3 (s,
1-Cxyl), 137.6 (s, 3,5-Cxyl), 134.2 (d, J(31P-13C) ) 20 Hz, PPh3),
134.0 (d, J(31P-13C) ) 12 Hz, PPh3), 133.5 (d, J(31P-13C) ) 39
Hz, PPh3), 128.9 (d, J(31P-13C) ) 9.5 Hz, PPh3), 125.3 (s, 2,6-
Cxyl), 122.4 (s, 4-Cxyl), 70.1 (s, br, 2/3/5/6-NBD CH), 66.7 (s, CH2
NBD), 52.1 (s, 1/4-NBD CH), 21.9 (s, C6H3(CH3)2), 4.7 (s, Si(CH3)2),
-14.6 (s, SiCH3). 29Si NMR (79.4 MHz, C6D6): δ -3.2 (s, SiMe2),
-96.3 (s, SiMe). 31P NMR (161.9 MHz, C6D6): δ 32.0 (d, 1J(103Rh-
31P) ) 156 Hz, 2J(117Sn-31P) ) 331 Hz, 2J(119Sn-31P) ) 348 Hz).
[MeSi[SiMe2N(3,5-xyl)]3SnRh(PPh3)(COD)] (4a). A mixture
of 200 mg (0.26 mmol) of MeSi[SiMe2N(3,5-xyl)]3SnLi(OEt2) (2a)
and 63 mg (0.13 mmol) of [RhCl(COD)]2 was suspended in
precooled toluene at -78 °C. The orange suspension was stirred
for 15 min before a solution of 68 mg (0.259 mmol) of PPh3 in
cold toluene was added. After a further 15 min of cooling it was
slowly warmed to room temperature and stirred for 2 h. Meanwhile
the color changed to red, and then insolubilities were removed by
centrifugation. The solvent was distilled in vacuo to get an orange
powder (230 mg) in 76% yield. FT-IR (KBr-disk): 3020 (w), 2941
(w), 2915 (w), 2887 (w), 1597 (s), 1581 (s), 1476 (m), 1434 (m),
1295 (m), 1261 (m), 1241 (m), 1156 (m), 1092 (m), 1032 (m), 958
(m), 825 (s, br), 694 (m), 645 (m), 524 (w) cm-1. 1H NMR (399.9
MHz, C6D6): δ 7.39 (s, 4H, PPh3), 7.10–6.97 (m, 17H, PPh3, 2,6-
Hxyl), 6.62 (s, 3H, 4-Hxyl), 5.95–5.86 (m, 2H, CHCOD), 3.28–3.20
(m, 2H, CHCOD), 2.28 (s, 18H, C6H3(CH3)2), 2.00–1.88 (m, 2H,
CH2 ), 1.74–1.63 (m, 2H, CH2 COD), 1.63–1.52 (m, 2H, CH2 COD),
COD
1.25–1.13 (m, 2H, CH2 COD), 0.58 (s, 18H, Si(CH3)2), 0.27 (s, 3H,
SiCH3). 13C NMR (100.6 MHz, C6D6): δ 155.1 (s, 1-Cxyl), 137.5
(s, 3,5-Cxyl), 134.7 (d, J(31P-13C) ) 39 Hz, PPh3), 134.4 (d, J(31P-
13C) ) 12 Hz, PPh3), 129.5 (d, J(31P-13C) ) 2.0 Hz, PPh3), 127.9
(d, J(31P-13C) ) 9.7 Hz, PPh3), 126.3 (s, 2,6-Cxyl), 125.7 (s, 4-Cxyl),
1
119Sn NMR (74.6 MHz, C6D6): δ -146.4 (dd, J(119Sn-103Rh) )
910 Hz, 2J(119Sn-31P)
)
349 Hz). Anal. Calcd for
C56H71N3PRhSi4Sn x C6H5CH3 (1151.1): C, 59.69; H, 6.31; N, 3.51.
Found: C, 59.68; H, 6.65; N, 3.64.
1
1
90.2 (d, J(103Rh-13C) ) 8.9 Hz, CHCOD), 86.2 (t, J(103Rh-13C)
) 8.5 Hz, CHCOD), 32.0 (s, CH2 COD), 29.1 (s, CH2 COD), 21.9 (s,
C6H3(CH3)2), 5.0 (s, Si(CH3)2), –9.8 (s, SiCH3). 29Si NMR (79.4
MHz, C6D6): δ -2.9 (s, SiMe2), -97.1 (s, SiMe). 31P NMR (161.9
MHz, C6D6): δ ) 24.5 (d, 1J(103Rh-31P) ) 144 Hz, 2J(117Sn-31P)
) 334 Hz, 2J(119Sn-31P) ) 350 Hz). 119Sn NMR (149.1 MHz,
C6D6): δ -176.0 (dd, 1J(119Sn-103Rh) ) 802 Hz, 2J(119Sn-31P) )
349 Hz). Anal. Calcd for C57H75N3PRhSi4Sn (1167.2): C, 58.66;
H, 6.48; N, 3.60. Found: C, 58.19; H, 6.78; N, 3.63.
[MeSi[SiMe2N(p-tol)]3SnRh(PPh3)(NBD)] (5b). The reaction
procedure was the same as for 4b using 502 mg (0.69 mmol) of
MeSi[SiMe2N(p-tol)]3SnLi(OEt2) (2b), 159 mg (0.35 mmol) of
[RhCl(NBD)]2, and 181 mg (0.69 mmol) of PPh3. Compound 5b
was isolated as a bright orange microcrystalline solid in 79% (604
mg) yield. Crystallization from a saturated solution in pentane at
-30 °C gave suitable crystals for X-ray analysis. FT-IR (KBr-disk):
3053 (w), 3011 (w), 2956 (w), 2891 (w), 1605 (w), 1497 (s), 1434
(m), 1236 (s), 1223 (s), 1091 (w), 914 (s), 844 (m), 813 (m), 778
(m), 744 (m), 698 (m), 543 (w), 528 (w), 509 (m) cm-1. 1H NMR
(199.9 MHz, C6D6): δ 7.20 (d, 3JHH ) 8.1 Hz, 6H, tol), 7.12–6.96
[MeSi[SiMe2N(p-tol)]3SnRh(PPh3)(COD)] (4b). A 500 mg
(0.68 mmol) amount of MeSi[SiMe2N(p-tol)]3SnLi(OEt2) (2b) and
168 mg (0.34 mmol) of [RhCl(COD)]2 were suspended at -78 °C
with precooled Et2O. After 30 min the orange reaction mixture was
filtered and added to solid PPh3 (178 mg, 0.68 mmol). The solution
was slowly warmed to room temperature after 1.5 h and the solvent
was removed in vacuo. The orange residue was washed twice with
small amounts of pentane and dried under reduced pressure to yield
the product (613 mg, 80% yield) as an orange powder. A
concentrated solution of 4b in Et2O was stored at -30 °C to give
orange crystals. FT-IR (KBr-disk): 3054 (w), 3012 (w), 2940 (m),
2890 (m), 1604 (w), 1498 (s), 1433 (w), 1222 (s), 1092 (w), 908
(s), 938 (m), 814 (m), 777 (m), 698 (w), 510 (m) cm-1. 1H NMR
(200 MHz, C6D6): δ 7.26–7.18 (m, 9H, tol, PPh3 overlap), 7.08–6.98
3
(m, 15H, PPh3), 6.84 (d, JHH ) 8.0 Hz, 6H, tol), 4.00 (s, br, 4H,
2/3/5/6-NBD CH), 3.09 (s, br, 2H, 1/4-NBD CH), 2.18 (s, 9H,
C6H4CH3), 0.82 (s, br, 2H, CH2 NBD), 0.64 (s, 18H, Si(CH3)2), 0.30
(s, 3H, SiCH3). 13C NMR (50.3 MHz, C6D6): δ 152.3 (s, tol), 133.9
(d, J(31P-13C) ) 12 Hz, PPh3), 132.8 (d, J(31P-13C) ) 40 Hz, PPh3),
129.6 (d, J(31P-13C) ) 20 Hz, PPh3), 129.1 (s, tol), 128.0 (s, PPh3),
127.9 (s, tol), 125.5 (s, tol), 69.2 (s, br, 2/3/5/6-NBD CH), 65.6 (s,
CH2 NBD), 51.5 (s, 1/4-NBD CH), 20.6 (s, C6H4CH3), 4.2 (s,
Si(CH3)2), -14.4 (s, SiCH3). 29Si NMR (39.7 MHz, C6D6): δ -2.4
(s, SiMe2), -91.1 (s, SiMe). 31P NMR (80.9 MHz, C6D6): δ )
33.5 (d, 1J(103Rh-31P) ) 159 Hz, 2J(117Sn-31P) ) 305 Hz, 2J(119Sn-
31P) ) 319 Hz). 119Sn NMR (74.6 MHz, C6D6): δ -147.7 (dd,
1J(119Sn-103Rh) ) 910 Hz, 2J(119Sn-31P) ) 315 Hz). Anal. Calcd
for C53H65N3PRhSi4Sn (1109.0): C, 57.40; H, 5.91; N, 3.79. Found:
C, 57.24; H, 6.06; N, 3.78.
3
(m, 12H, PPh3), 6.89 (d, JHH ) 7.9 Hz, 6H, tol), 5.82 (s, br, 2H,
CHCOD), 3.36 (s, br, 2H, CHCOD), 2.24 (s, 9H, C6H4CH3), 1.80 (s,
br, 2H, CH2 COD), 1.53 (s, br, 4H, CH2 COD), 1.20 (s, br, 2H, CH2
COD), 0.57 (s, 18H, Si(CH3)2), 0.36 (s, 3H, SiCH3). 13C NMR (50.3
MHz, C6D6): δ 151.9 (s, tol), 134.6 (d, J(31P-13C) ) 12 Hz, PPh3),
134.2 (d, J(31P-13C) ) 40 Hz, PPh3), 129.8 (s, tol), 129.7 (d, J(31P-
13C) ) 13 Hz, PPh3), 129.5 (s, tol), 128.9 (s, tol), 127.5 (s, PPh3),
[MeSi[SiMe2N(3,5-xyl)]3SnRh(PPh3)(η6-C6H6)] (6a). A solu-
tion of 68 mg (0.26 mmol) of PPh3 in pentane and 2 mL of benzene
was cooled to -78 °C. In the cold it was added to a solid mixture
of 200 mg (0.26 mmol) of MeSi[SiMe2N(3,5-xyl)]3SnLi(OEt2) (2a)
and 50 mg (0.13 mmol) of [RhCl(C2H4)2]2. The yellow suspension
was stirred for 15 min. Then it was allowed to warm to room
temperature, while a color change to brown occurred. Insolubilities
were removed by centrifugation and solvents in vacuo to yield 258
mg (87%) of a brown powder. FT-IR (Nujol): 3033 (w), 2946 (m),
2893 (m), 2859 (w), 1596 (m), 1583 (s), 1478 (m), 1458 (m), 1436
(m), 1352 (w), 850 (m), 830 (m), 781 (m), 746 (m), 701 (m), 647
1
1
91.1 (d, J(103Rh-13C) ) 12 Hz, CHCOD), 87.1 (d, J(103Rh-13C)
) 12 Hz, CHCOD), 31.4 (s, br, CH2 COD), 29.5 (s, br, CH2 COD),
20.7 (s, C6H4CH3), 4.3 (s, Si(CH3)2), –14.3 (s, SiCH3). 29Si NMR
(39.7 MHz, C6D6): δ -2.3 (s, SiMe2), -91.8 (s, SiMe). 31P NMR
(80.9 MHz, C6D6): δ ) 29.4 (d, 1J(103Rh-31P) ) 148 Hz, 2J(117Sn-
31P) ) 296 Hz, 2J(119Sn-31P) ) 309 Hz). 119Sn NMR (149.1 MHz,
C6D6): δ -176.5 (dd, 1J(119Sn-103Rh) ) 806 Hz, 2J(119Sn-31P) )
311 Hz). Anal. Calcd for C54H69N3PRhSi4Sn (1125.1): C, 57.65;
H, 6.18; N, 3.73. Found: C, 57.83; H, 6.32; N, 3.58.
1
(m), 598 (m) cm-1. H NMR (400 MHz, C6D6): δ 7.01–6.98 (m,
6H, PPh3), 6.96 (s, 6H, η6-C6H6), 6.96–6.92 (m, 9H, PPh3), 6.92
(s, 6H, 2,6-Hxyl), 6.65 (s, 3H, 4-Hxyl), 2.29 (s, 18H, C6H3(CH3)2),
0.57 (s, 18H, Si(CH3)2), 0.28 (s, 3H, SiCH3). 1H NMR (400 MHz,
C6D12): δ 7.15–7.08 (m, 3H, PPh3), 7.07–7.00 (m, 6H, PPh3),
6.87–6.76 (m, 6H, PPh3), 6.60 (s, 6H, 2,6-Hxyl), 6.54 (s, 3H, 4-Hxyl),
[MeSi[SiMe2N(3,5-xyl)]3SnRh(PPh3)(NBD)] (5a). The reaction
procedure was the same as for 4a using 200 mg (0.26 mmol) of
MeSi[SiMe2N(3,5-xyl)]3SnLi(OEt2) (2a), 59 mg (0.13 mmol) of
[RhCl(NBD)]2, and 68 mg (0.26 mmol) of PPh3. Compound 5a

Triamidostannates(II)
Organometallics, Vol. 27, No. 4, 2008 531

532 Organometallics, Vol. 27, No. 4, 2008
Kilian et al.
5.19 (s, 6H, η6-C6H6), 2.23 (s, 18H, C6H3(CH3)2), 0.18 (s, 18H,
Si(CH3)2), 0.06 (s, 3H, SiCH3). 13C NMR (100.6 MHz, C6D6): δ
154.3 (s, 1-Cxyl), 139.6 (d, J(31P-13C) ) 46 Hz, PPh3), 137.1 (s,
3,5-Cxyl), 133.7 (d, J(31P-13C) ) 13 Hz, PPh3), 129.0 (d, J(31P-
13C) ) 2.1 Hz, PPh3), 128.6 (s, η6-C6H6), 127.8 (s, 2,6-Cxyl), 127.5
(d, J(31P-13C) ) 10 Hz, PPh3), 122.5 (s, 4-Cxyl), 21.9 (s,
C6H3(CH3)2), 5.0 (s, Si(CH3)2), –14.6 (s, SiCH3). 29Si NMR (79.4
MHz, C6D6): δ –2.7 (s, SiMe2), -97.4 (s, SiMe). 13C NMR (100.6
MHz, C6D12): δ ) 153.6 (s, 1-Cxyl), 139.1 (d, J(31P-13C) ) 44 Hz,
PPh3), 136.2 (s, 3,5-Cxyl), 133.3 (d, J(31P-13C) ) 12 Hz, PPh3),
128.1 (s, PPh3), 127.3 (s, 2,6-Cxyl), 126.7 (d, J(31P-13C) ) 10 Hz,
PPh3), 121.7 (s, 4-Cxyl), 96.3 (s, η6-C6H6), 21.0 (s, C6H3(CH3)2),
3.7 (s, Si(CH3)2), -15.7 (s, SiCH3). 31P NMR (161.9 MHz, C6D6):
δ 39.9 (d, 1J(103Rh-31P) ) 214 Hz, 2J(117Sn-31P) ) 343 Hz,
2J(119Sn-31P) ) 358 Hz). 119Sn NMR (149.1 MHz, C6D6): δ –175.5
(400 MHz, C6D12): δ 7.14 – 7.01 (m, 9H, PPh3), 6.90–6.82 (m,
6H, PPh3), 6.58 (s, 6H, 2,6-Hxyl), 6.54 (s, 3H, 4-Hxyl), 6.10–6.05
3
(m, 1H, η6-C6H5CH3), 5.07 (t, 2H, JHH ) 6.2 Hz, η6-C6H5CH3),
3
4.28 (d, 2H, JHH ) 6.2 Hz, η6-C6H5CH3), 2.23 (s, 18H,
C6H3(CH3)2), 1.71 (s, 3H, η6-C6H5CH3), 0.18 (s, 18H, Si(CH3)2),
0.07 (s, 3H, SiCH3). 13C NMR (100.6 MHz, C6D6): δ 154.2 (s,
1-Cxyl), 139.1 (d, J(31P-13C) ) 46 Hz, PPh3), 137.1 (s, 3,5-Cxyl),
133.7 (d, J(31P-13C) ) 12 Hz, PPh3), 129.3 (s, η6-C6H5CH3), 128.9
(d, J(31P-13C) ) 2.3 Hz, PPh3), 128.5 (s, η6-C6H5CH3), 128.3 (s,
η6-C6H5CH3), 127.7 (s, 2,6-Cxyl), 127.4 (d, J(31P-13C) ) 10 Hz,
PPh3), 125.6 (s, η6-C6H5CH3), 122.5 (s, 4-Cxyl), 21.8 (s,
C6H3(CH3)2), 21.4 (s, η6-C6H5CH3), 4.9 (s, Si(CH3)2), -14.7 (s,
SiCH3). 13C NMR (100.6 MHz, C6D12): δ 153.8 (s, 1-Cxyl), 136.2
(s, 3,5-Cxyl), 133.1 (d, J(31P-13C) ) 13 Hz, PPh3), 128.0 (s, br,
PPh3), 127.3 (s, 2,6-Cxyl), 126.8 (d, J(31P-13C) ) 10 Hz, PPh3),
121.8 (s, 4-Cxyl), 98.1 (s, η6-C6H5CH3), 97.7 (s, η6-C6H5CH3), 93.0
(s, η6-C6H5CH3), 21.0 (s, C6H3(CH3)2), 19.4 (s, η6-C6H5CH3), 3.7
(s, Si(CH3)2), -15.7 (s, SiCH3). 29Si NMR (79.4 MHz, C6D6): δ
-2.7 (s, SiMe2), -97.4 (s, SiMe). 31P NMR (161.9 MHz, C6D6):
δ 39.9 (d, 1J(103Rh-31P) ) 215 Hz, 2J(117Sn-31P) ) 343 Hz,
2J(119Sn-31P) ) 358 Hz). 119Sn NMR (149.1 MHz, C6D6): δ
-175.4 (dd, 1J(119Sn-103Rh) ) 1165 Hz, 2J(119Sn-31P) ) 358 Hz).
Anal. Calcd for C56H71N3PRhSi4Sn (1151.1): C, 58.43; H, 6.22;
N, 3.65. Found: C, 58.16; H, 6.37; N, 3.64.
1
2
(dd, J(119Sn-103Rh) ) 1159 Hz, J(119Sn-31P) ) 360 Hz). Anal.
Calcd for C55H69N3PRhSi4Sn (1137.1): C, 58.09; H, 6.12; N, 3.70.
Found: C, 57.76; H, 6.49; N, 3.75.
[MeSi[SiMe2N(p-tol)]3SnRh(PPh3)(η6-C6H6)] (6b). An analo-
gous procedure as for preparing 6a, using 200 mg (0.27 mmol) of
MeSi[SiMe2N(p-tol)]3SnLi(OEt2) (2b), 53 mg (0.14 mmol) of
[RhCl(C2H4)2]2, and 72 mg of PPh3 (0.27 mmol), gave compound
6b as a brown microcrystalline solid in yield 41% (124 mg). FT-
IR (KBr-disk): 3054 (w), 2958 (m), 1615 (w), 1512 (s), 1499 (s),
1436 (s), 1286 (m), 1261 (s), 1120 (m), 1093 (s), 1027 (m), 909
(m), 812 (s), 747 (w), 694 (s), 541 (m) cm-1. 1H NMR (400 MHz,
[MeSi[SiMe2N(p-tol)]3SnRh(PPh3)(η6-C6H5CH3)] (7b). An
analogous procedure as that described for the preparation of 7a,
using 200 mg (0.27 mmol) of MeSi[SiMe2N(p-tol)]3SnLi(OEt2)
(2b), 53 mg (0.14 mmol) of [RhCl(C2H4)2]2, and 72 mg (0.27 mmol)
of PPh3, gave compound 7a as a brown microcrystalline solid in
58% (176 mg) yield. FT-IR (KBr-disk): 3050 (w), 3015 (w), 2938
(w), 2890 (w), 1603 (m), 1498 (s), 1435 (m), 1232 (s), 1223 (s),
1092 (m), 1028 (w), 906 (s), 849 (m), 778 (m), 745 (m), 696 (s),
530 (m) cm-1. 1H NMR (400 MHz, C6D6): δ 7.13 – 6.96 (m, 15H,
PPh3, 6H, tol, 5H, η6-C6H5CH3), 6.93 (d, 3JHH ) 8.1 Hz, 6H, tol),
2.30 (s, 9H, C6H4CH3), 2.10 (s, 3H, η6-C6H5CH3), 0.56 (s, 18H,
Si(CH3)2), 0.27 (s, 3H, SiCH3). 1H NMR (600 MHz, C6D12): δ
3
C6D6): δ 7.82–7.69 (m, 4H, PPh3), 7.10 (d, JHH ) 8.2 Hz, 6H,
tol), 7.07–7.01 (m, 9H, PPh3), 6.99 (s, 6H, η6-C6H6), 6.93 (d, 3JHH
) 8.2 Hz, 6H, tol), 6.90–6.79 (m, 2H, PPh3), 2.30 (s, 9H, C6H4CH3),
0.55 (s, 18H, Si(CH3)2), 0.26 (s, 3H, SiCH3). 1H NMR (600 MHz,
C6D12): δ 7.16–7.00 (m, 9H, PPh3), 6.95–6.81 (m, 6H, PPh3), 6.86
(d, 3JHH ) 3.6 Hz, 6H, tol), 6.84 (d, 3JHH ) 3.5 Hz, 6H, tol), 5.21
(s, 6H, η6-C6H6), 2.33 (s, 9H, C6H4CH3), 0.23 (s, 18H, Si(CH3)2),
0.11 (s, 3H, SiCH3). 13C NMR (100.6 MHz, C6D6): δ 151.6 (s,
1-Ctol),), 134.1 (d, J(31P-13C) ) 12 Hz, PPh3), 129.0 (d, J(31P-
13C) ) 4.6 Hz, PPh3), 128.6 (d, J(31P-13C) ) 8.4 Hz, PPh3), 127.5
(d, J(31P-13C) ) 10 Hz, PPh3), 21.1 (s, C6H3(CH3)2), 4.8 (s,
Si(CH3)2), -14.2 (s, SiCH3). 13C NMR (100.6 MHz, C6D12): δ
151.0 (s, 1-Ctol), 140.2 (d, J(31P-13C) ) 52 Hz, PPh3), 133.6 (d,
J(31P-13C) ) 12 Hz, PPh3), 128.6 (s, 3,5-Ctol), 128.2 (s, PPh3), 127.7
(s, 2,6-Ctol), 126.7 (d, J(31P-13C) ) 10 Hz, PPh3), 124.9 (s, 4-Cxyl),
96.6 (s, η6-C6H6), 20.3 (s, C6H4CH3), 3.7 (s, Si(CH3)2), -15.5 (s,
SiCH3). 29Si NMR (79.4 MHz, C6D6): δ –2.6 (s, SiMe2), -93.7
(s, SiMe). 31P NMR (161.9 MHz, C6D6): δ 42.8 (d, 1J(103Rh-31P)
) 215 Hz, 2J(117Sn-31P) ) 322 Hz, 2J(119Sn-31P) ) 343 Hz). 119Sn
3
7.12–7.04 (m, 9H, PPh3), 7.00–6.95 (m, 6H, PPh3), 6.85 (d, JHH
3
) 8.4 Hz, 6H, tol), 6.83 (d, JHH ) 8.4 Hz, 6H, tol), 6.00 (t, 1H,
3
3JHH ) 6.1 Hz, η6-C6H5CH3), 5.09 (t, 2H, JHH ) 6.2 Hz,
3
η6-C6H5CH3), 4.22 (d, 2H, JHH ) 6.2 Hz, η6-C6H5CH3), 2.32 (s,
9H, C6H4CH3), 1.83 (s, 3H, η6-C6H5CH3), 0.22 (s, 18H, Si(CH3)2),
0.10 (s, 3H, SiCH3). 13C NMR (100 MHz, C6D6): δ 151.6 (s, 1-Ctol),
139.4 (d, J(31P-13C) ) 45 Hz, PPh3), 137.9 (s, η6-C6H5CH3), 134.1
(d, J(31P-13C) ) 13 Hz, PPh3), 129.3 (s, 3,5-Ctol), 129.2 (s, η6-
C6H5CH3), 129.0 (d, J(31P-13C) ) 3.5 Hz, PPh3), 128.7 (s, η6-
C6H5CH3), 128.6 (s, 2,6-Ctol), 128.3 (s, η6-C6H5CH3), 127.5 (d,
J(31P-13C) ) 10 Hz, PPh3), 125.7 (s, 4-Ctol), 21.4 (s, η6-CH3C6H5),
21.1 (s, C6H3(CH3)2), 4.8 (s, Si(CH3)2), -14.2 (s, SiCH3). 13C NMR
(150.9 MHz, C6D12): δ 151.2 (s, 1-Ctol), 136.9 (s, 4-Ctol), 133.5 (d,
J(31P-13C) ) 13 Hz, PPh3), 129.3 (s, 3,5-Ctol), 128.7 (s, 2,6-Ctol),
128.2 (s, br, PPh3), 128.0 (d, J(31P-13C) ) 31 Hz, PPh3), 126.7 (d,
J(31P-13C) ) 10 Hz, PPh3), 100.1 (s, η6-C6H5CH3), 97.1 (s, η6-
C6H5CH3), 92.4 (s, η6-C6H5CH3), 20.2 (s, C6H3(CH3)2), 18.6 (s,
η6-CH3C6H5), 3.6 (s, Si(CH3)2), -15.5 (s, SiCH3). 29Si NMR (79.4
MHz, C6D6): δ -2.1 (s, SiMe2), -93.7 (s, SiMe). 31P NMR (242.9
MHz, C6D6): δ 42.9 (d, 1J(103Rh-31P) ) 215 Hz, 2J(117Sn-31P) )
323 Hz, 2J(119Sn-31P) ) 338 Hz). 119Sn NMR (149.1 MHz, C6D6):
1
NMR (149.1 MHz, C6D6): δ –179.7 (dd, J(119Sn-103Rh) ) 1170
2
Hz, J(119Sn-31P) ) 337 Hz). Anal. Calcd for C52H63N3PRhSi4Sn
(1095.0): C, 57.04; H, 5.80; N, 3.84. Found: C, 56.80; H, 5.89; N,
4.02.
[MeSi[SiMe2N(3,5-xyl)]3SnRh(PPh3)(η6-C6H5CH3)] (7a). A
solution of 68 mg (0.26 mmol) of PPh3 in pentane and 5 mL of
toluene was cooled to -78 °C. In the cold it was added to a solid
mixture of 200 mg (0.26 mmol) of MeSi[SiMe2N(3,5-
xyl)]3SnLi(OEt2) (2a) and 50 mg (0.13 mmol) of [RhCl(C2H4)2]2.
The yellow suspension was stirred for 15 min and then allowed to
warm to room temperature. During the course of this procedure, a
change of color of the reaction mixture from yellow to brown was
observed. Insolubilities were removed by centrifugation and solvents
in vacuo to yield 203 mg (68%) of a brown powder. FT-IR (KBr-
disk): 3022 (w), 2954 (w), 2914 (w), 2858 (w), 1595 (s), 1582 (s),
1477 (m), 1435 (m), 1351 (w), 1294 (m), 1241 (m), 1156 (s), 1092
(m), 1030 (m), 956 (m), 908 (s), 854 (s), 775 (s), 703 (s), 644 (m),
530 (m) cm-1. 1H NMR (400 MHz, C6D6): δ 7.13 – 7.09 (m, 1H,
η6-C6H5CH3), 7.06–7.02 (m, 1H, PPh3), 7.02–6.98 (m, 4H, η6-
C6H5CH3), 6.98–6.92 (m, 14H, PPh3), 6.91 (s, 6H, 2,6-Hxyl), 6.65
(s, 3H, 4-Hxyl), 2.29 (s, 18H, C6H3(CH3)2), 2.10 (s, 3H, η6-
C6H5CH3), 0.57 (s, 18H, Si(CH3)2), 0.27 (s, 3H, SiCH3). 1H NMR
1
2
δ -182.8 (dd, J(119Sn-103Rh) ) 1172 Hz, J(119Sn-31P) ) 338
Hz). Anal. Calcd for C53H65N3PRhSi4Sn (1109.0): C, 57.40; H, 5.91;
N, 3.79. Found: C, 56.97; H, 5.71; N, 3.56.
[MeSi[SiMe2N(3,5-xyl)]3SnIr(PPh3)(COD)] (8a). A mixture of
400 mg (0.52 mmol) of MeSi[SiMe2N(3,5-xyl)]3SnLi(OEt2) (2a)
and 158 mg (0.24 mmol) of [IrCl(COD)]2 was suspended in
precooled Et2O at -78 °C. The orange suspension was stirred for
15 min before it was transferred to 126 mg (0.48 mmol) of PPh3.
While it was slowly warmed to room temperature the color changed
to red-brown. Then the solvent was distilled in vacuo and the residue

Triamidostannates(II)
Organometallics, Vol. 27, No. 4, 2008 533
1
1
was extracted with hexane. After removing the solvent in vacuo, a
red-brown powder was isolated in 80% (471 mg) yield. FT-IR (KBr-
disk): 3020 (w), 2942 (m), 2891 (w), 1598 (s), 1582 (s), 1477 (w),
1434 (m), 1297 (m), 1243 (m), 1158 (m), 1092 (w), 1035 (m), 960
tolIr), 81.0 (d, J(103Rh-13C) ) 2 Hz, CHCOD), 80.8 (d, J(103Rh-
13C) ) 4.8 Hz, CHCOD), 73.9 (d, 1J(103Rh-13C) ) 6.0 Hz, CHCOD),
71.7 (d, J(103Rh-13C) ) 2.4 Hz, CHCOD), 36.2, 33.9, 30.1, 29.3
1
(s, CH2 COD), 21.0, 20.8, 20.2 (s, C6H4CH3), 7,1, 6.8, 2.8, 2.8, 2.4,
1.6, 1.4 (s, Si(CH3)2), -14.6 (s, SiCH3). 29Si NMR (79.4 MHz,
C6D6): δ 0.4 (d, J ) 1.6 Hz, SiMe2), 0.2 (d, J ) 1.8 Hz, SiMe2),
-2.8 (d, J ) 1.1 Hz, SiMe2), -93.2 (s, SiMe). 31P NMR (161.9
1
(w), 849 (s), 827 (s), 695 (m), 647 (w), 532 (w) cm-1. H NMR
(399.9 MHz, C6D6): δ 7.06–6.97 (m, 15H, PPh3), 6.94 (s, 6H, 2,6-
Hxyl), 6.59 (s, 2H, 4-Hxyl), 5.65 (s, br, 2H, CHCOD), 2.68 (s, br, 2H,
CHCOD), 2.25 (s, 18H, C6H3(CH3)2), 1.85–1.68 (m, 2H, CH2 COD),
1.60–1.45 (m, 2H, CH2 COD), 1.33 – 1.17 (m, 2H, CH2 COD), 0.78 –
0.67 (m, 2H, CH2 COD), 0.59 (s, 18H, Si(CH3)2), 0.27 (s, 3H, SiCH3).
13C NMR (100.6 MHz, C6D6): δ 154.8 (s, 1-Cxyl), 137.4 (s, 3,5-
Cxyl), 134.5 (d, J(13C-31P) ) 11 Hz, PPh3), 133.8 (d, J(13C-31P) )
24 Hz, PPh3), 129.7 (d, J(13C-31P) ) 2.3 Hz, PPh3), 127.9 (d, J(13C-
31P) ) 10 Hz, PPh3, von C6D6), 126.0 (s, 2,6-Cxyl), 122.6 (s, 4-Cxyl),
75.3 (d, 2J(31P-13C) ) 5.2 Hz, CHCOD), 73.3 (d, 2J(31P-13C) ) 3.2
Hz, CHCOD), 32.8 (s, CH2 COD), 21.8 (s, C6H3(CH3)2), 5.0 (s,
Si(CH3)2), –14.6 (s, SiCH3). 29Si NMR (79.4 MHz, C6D6): δ -1.9
(s, SiMe2), -96.9 (s, SiMe). 31P NMR (161.9 MHz, C6D6): δ )
18.1 (s, 2J(31P-117Sn) ) 213 Hz, 2J(31P-119Sn) ) 223 Hz). 119Sn-
NMR (149.1 MHz, C6D6): δ -101.1 (d, 2J(31P-119Sn) ) 224 Hz).
Anal. Calcd for C57H75IrN3PSi4Sn (1256.5): C, 54.49; H, 6.02; N,
3.34. Found: C, 54.81; H, 6.30; N, 3.49.
MHz, C6D6): δ 5.5 (s, J(117Sn-31P) ) 1639 Hz, J(119Sn-31P) )
1713 Hz). 119Sn NMR (149.1 MHz, C6D6): δ -162.5 (d, 2J(119Sn-
31P) ) 1714 Hz). Anal. Calcd for C54H69IrN3PSi4Sn (1214.4): C,
53.41; H, 5.73; N, 3.46. Found: C, 53.67; H, 5.90; N, 3.40.
Crystal Structure Determinations. Crystal data and details of
the structure determinations are listed in Table 1. Intensity data
were collected at low temperature with Bruker AXS Smart 1000
CCD and Enraf-Nonius Kappa CCD (complex 6b) diffractometers
(Mo KR radiation, graphite monochromator, λ ) 0.71073 Å). Data
were corrected for Lorentz, polarization and absorption effects
(semiempirical, SADABS).42 The structures were solved by the
heavy atom method combined with structure expansion by direct
methods applied to difference structure factors (DIRDIF)43 or by
direct methods (SHELXS-97)44 (complex 8b) and refined by full-
matrix least-squares methods based on F2 with all measured unique
reflections.44 Due to heavy disorder and fractional occupancy,
electron density attributed to solvent of crystallization was removed
from the structures (and the corresponding Fobs) of 2a, 3a, and 5b
with the SQUEEZE procedure,45 as implemented in PLATON.46
All non-hydrogen atoms were given anisotropic displacement
parameters. Hydrogen atoms were generally input at calculated
positions and refined with a riding model. When justified by the
quality of the data, the positions of some hydrogen atoms (those
on the carbon atoms involved in coordination to Rh or Ir, and the
hydride in 8b) were taken from difference Fourier syntheses and
refined.
2
2
[MeSi[SiMe2N(p-tol)]2[SiMe2N(2-C6H3-4-CH3)]SnIr(H)(PPh3)-
(COD)] (8b). A mixture of 200 mg (0.27 mmol) of MeSi[SiMe2N(p-
tol)]3SnLi(OEt2) (2b) and 92 mg (0.14 mmol) of [IrCl(COD)]2 was
suspended with precooled Et2O at -78 °C. The dark red reaction
mixture was stirred for 10 min, then a solution of 72 mg (0.27
mmol) of PPh3 in Et2O was subsequently added and the reaction
mixture warmed to room temperature. After concentration in vacuo
and centrifugation, the centrifugate was stored at 10 °C gave dark
yellow crystals (528 mg, 80%). FT-IR (KBr-disk): 3060 (vw), 2939
(w), 2891 (w), 2058 (vw), 1604 (w), 1500 (s), 1433 (w), 1235 (s),
1086 (w), 1043 (w), 919 (s), 854 (m), 804 (m), 745 (w), 696 (m),
1
524 (m) cm-1. H NMR (399.9 MHz, C6D6): δ 7.60–7.42 (s, br,
Acknowledgment. This research was supported by the
University of Heidelberg and the Fonds der Chemischen
Industrie (Germany). We thank the reviewers for helpful
comments.
2H, PPh3), 7.41–7.32 (m, 7H, tol, PPh3), 7.08–7.01 (m, 7H, tol,
PPh3), 6.98–6.85 (m, 7H, tol, PPh3), 6.64 (d, 2H, tol), 6.50–6.30
(s, br, 1H, PPh3), 4.41–4.32 (m, 1H, CHCOD), 4.18–4.04 (m, 1H,
CHCOD), 3.64–3.51 (m, 1H, CHCOD), 3.01–2.90 (m, 1H, CHCOD),
2.22–2.13 (m, 1H, CH2 COD), 2.11 (s, 3H, C6H4CH3), 2.03 (s, 3H,
C6H4CH3), 1.94–1.82 (m, 1H, CH2 COD), 1.78 (s, 3H, C6H3CH3),
1.60–1.36 (m, 4H, CH2 COD), 1.34–1.16 (m, 2H, CH2 COD), 1.06 (s,
3H, Si(CH3)2), 1.01 (s, 3H, Si(CH3)2), 0.92 (s, 3H, Si(CH3)2), 0.79
(s, 3H, Si(CH3)2), 0.54 (s, 3H, Si(CH3)2), 0.49 (s, 3H, Si(CH3)2),
0.39 (s, 3H, SiCH3), -12.23 (d, 2J(31P-1H) ) 24 Hz, 2J(117/119Sn-
1H) ) 131 Hz, 1H, SnIr(H)P). 13C NMR (100.6 MHz, C6D6,): δ
155.3 (s, br, tolIr), 151.3 (s, tol), 151.1 (s, tol), 143.5 (d, J(31P-13C)
) 11 Hz, PPh3), 134.3 (d, J(31P-13C) ) 9.2 Hz, PPh3), 130.5 (d,
Supporting Information Available: CIF files giving the crystal
data for compounds 2a, 3a, 4b, 5a, 5b, 6b, and 8b. This material
is available free of charge via the Internet at http://pubs.acs.org.
OM700960P
(42) Sheldrick, G. M. SADABS; Bruker AXS,2004-2007.
(43) (a) Parthasarathi, V.; Beurskens, P. T.; Bruins Slot, H. J. Acta
Crystallogr. 1983, A39, 860. (b) Beurskens, P. T.; Beurskens, G.; de Gelder,
R.; Garcia-Granda, S.; Gould, R. O.; Israel, R.; Smits, J. M. M. DIRDIF-
99; University of Nijmegen: The Netherlands, 1999.
(44) Sheldrick, G. M. SHELXS-97; University of Göttingen, 1997.
(45) v. d. Sluis, P.; Spek, A. L. Acta Crystallogr. 1990, A46, 194.
(46) Spek, A. L. J. Appl. Crystallogr. 2003, 36, 7.
2
J(31P-13C) ) 33 Hz, PPh3), 130.1 (d, J(31P-13C) ) 9.2 Hz, P-Ir-
C6H3Me), 130.1 (s, br, tolIr), 129.7 (d, J(31P-13C) ) 2.1 Hz, PPh3),
129.6 (s, tol), 128.8 (s, br, tolIr), 128.3 (s, tol), 128.1 (s, tol), 128.0
(s, tol), 127.8 (s, br, tolIr), 124.2 (s, tol), 124.1 (s, tol), 124.0 (s, br,