Versatile N,C,N coordination behavior of a monoanionic aryldiamine ligand in ruthenium(II) complexes: Syntheses and crystal structures of [RuII{C6H3(CH2NMe2) 2-2,6}X(L)] (L = Norbornadiene, X = Cl, SO3CF3; L = PPh3, X = I)

Article abstract of DOI:10.1021/om950700q

The monoanionic ligand [C₆H₃(CH₂NMe₂)₂-2,6] ^-, a potentially terdentate N,C,N bonding system, has been employed to synthesize a series of new ruthenium(II) complexes [Ru-{C₆H₃(CH₂NMe₂) ₂-2,6}X(L)] (L = PPh₃, X = Cl (2a), I (2b); L = norbornadiene (nbd), X = Cl (4), η¹-OSO₂CF₃ (5)) and [Ru{C₆H₃(CH₂NMe₂) ₂-2,6}(2,2′:6′,2″-terpyridine)]Cl (3). X-ray crystal structures of 2b and 3-5 have been determined, in which the N,C,N coordination geometry with respect to the metal center is found to differ considerably. In each complex the aryldiamine ligand is terdentate, η³-N,C,N-bonded as a six electron donor system. However, depending on the other ligands in the Ru(II) coordination sphere, this ligand demonstrates considerable flexibility in adopting coordination geometries which range from meridional in 3 through pseudomeridional in 2b to pseudo facial in 4 and 5. In the structures of 4 and 5 significant distortions of the aryl ring, involving bending of the six-membered ring into a boatlike conformation, are found. The different combinations of the N,C,N ligand with sets of other ligands lead to a range of metal geometries, i.e. square pyramidal in 2b, octahedral in 3, and bicapped tetrahedral in 4 and 5.

Full text of DOI:10.1021/om950700q

Organometallics 1996, 15, 941-948
941
Ver sa tile N,C,N Coor d in a tion Beh a vior of a Mon oa n ion ic
Ar yld ia m in e Liga n d in Ru th en iu m (II) Com p lexes:
Syn th eses a n d Cr ysta l Str u ctu r es of
[Ru II{C6H3(CH2NMe2)2-2,6}X(L)] (L ) Nor bor n a d ien e, X )
Cl, SO3CF 3; L ) P P h 3, X ) I) a n d
[Ru II{C6H3(CH2NMe2)2-2,6}(2,2′:6′,2′′-ter p yr id in e)]Cl
J ean-Pascal Sutter,† Stuart L. J ames,† Pablo Steenwinkel,† Thomas Karlen,†
David M. Grove,† Nora Veldman,‡ Wilberth J . J . Smeets,‡
Anthony L. Spek,‡,§ and Gerard van Koten*,†
Debye Institute, Department of Metal-Mediated Synthesis, Utrecht University, Padualaan 8,
3584 CH Utrecht, The Netherlands, and Bijvoet Center for Biomolecular Research, Laboratory
of Crystal Chemistry, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands
Received September 5, 1995X
The monoanionic ligand [C6H3(CH2NMe2)2-2,6]-, a potentially terdentate N,C,N bonding
system, has been employed to synthesize a series of new ruthenium(II) complexes [Ru-
{C6H3(CH2NMe2)2-2,6}X(L)] (L ) PPh3, X ) Cl (2a ), I (2b); L ) norbornadiene (nbd), X ) Cl
(4), η1-OSO2CF3 (5)) and [Ru{C6H3(CH2NMe2)2-2,6}(2,2′:6′,2′′-terpyridine)]Cl (3). X-ray
crystal structures of 2b and 3-5 have been determined, in which the N,C,N coordination
geometry with respect to the metal center is found to differ considerably. In each complex
the aryldiamine ligand is terdentate, η3-N,C,N-bonded as a six electron donor system.
However, depending on the other ligands in the Ru(II) coordination sphere, this ligand
demonstrates considerable flexibility in adopting coordination geometries which range from
meridional in 3 through pseudomeridional in 2b to pseudofacial in 4 and 5. In the structures
of 4 and 5 significant distortions of the aryl ring, involving bending of the six-membered
ring into a boatlike conformation, are found. The different combinations of the N,C,N ligand
with sets of other ligands lead to a range of metal geometries, i.e. square pyramidal in 2b,
octahedral in 3, and bicapped tetrahedral in 4 and 5.
Sch em e 1. Liga n d s for Or ga n om eta llic Ca vities
In tr od u ction
Recently we formulated the concept of organometallic
cavities, i.e. cavities in which anionic polydentate
ligands have at least one anionic C-donor atom binding
to the metal center to form a M-C σ-bond.1 Such a
M-C bond can only be disrupted by metathesis with a
strong nucleophile or by reactions based on heterolytic
or homolytic bond cleavage. Consequently, a metal is
more tightly contained in an organometallic cavity than
in a ligand cavity system that only employs neutral two
electron donor atoms. Of course, in an organometallic
cavity the other binding components will often be
neutral donor atom to metal interactions and for an
organometallic cavity one can therefore envisage the use
of polydentate ligands that are either symmetrical, type
A, or unsymmetrical, type B (Scheme 1).1,2 More
elaborate examples include the potentially pentadentate
N′,N,C,N,N′-bonding, monoanionic ligand in cation C3
and monoanionic oxygen donor systems of the type
{C6H3O(CH2CH2O)n-3}- (n ) 3, 4) employed by Bick-
elhaupt et al.4
We are currently examining the various factors which
determine the flexibility of the coordination geometry
exhibited by the monoanionic aryldiamine ligand
[C6H3(CH2NMe2)2-2,6]-, which is formally a 6-electron
donor when it is terdentate N,C,N′-bonded to a metal
center. In this way, we aim to obtain a better under-
standing of the steric and geometric properties and
coordination potential of this and related ligands in
complexes that exhibit homogeneous catalytic activity;
for example, [Ni{C6H3(CH2NMe2)2-2,6}X] catalyzes the
Kharasch addition reaction of halocarbons to alkenes
* Author to whom correspondence should be addressed.
† Debye Institute.
‡ Bijvoet Center.
§ Author for enquiries relating to the crystallographic studies.
X Abstract published in Advance ACS Abstracts, J anuary 1, 1996.
(1) van Koten, G. Pure Appl. Chem. 1989, 61, 1681.
(2) Alsters, P. L.; Engel, P. F.; Hogerheide, M. P.; Copijn, M.; Spek,
A. L.; van Koten, G. Organometallics 1993, 12, 1831.
(3) Kapteijn, G. M.; Ooyevaar-Wehman, I. C. M.; Grove, D. M.;
Smeets, W. J . J .; Spek, A. L.; van Koten, G. Angew. Chem., Int. Ed.
Engl. 1993, 32, 72.
(4) Markies, P. R.; Akkerman, O. S.; Bickelhaupt, F.; Smeets, W. J .
J .; Spek, A. L. J . Am. Chem. Soc., 1988, 110, 4824. Markies, P. R.;
Akkerman, O. S.; Bickelhaupt, F.; Smeets, W. J . J .; Spek, A. L. Angew.
Chem. 1988, 100, 1143. For a review see: Markies, P. R.; Akkerman,
O. S.; Bickelhaupt, F.; Smeets, W. J . J .; Spek, A. L. Adv. Organomet
Chem. 1991, 32, 147.
0276-7333/96/2315-0941$12.00/0 © 1996 American Chemical Society

942 Organometallics, Vol. 15, No. 3, 1996
Sutter et al.
Sch em e 2. P r ep a r a tion of 2a ,b, a n d 3
F igu r e 1. Thermal motion ellipsoid plot (50% probability
level) of 2b. H atoms were omitted for clarity.
with high selectivity.5a-d The utility of this type of
ligand system has been further demonstrated by using
the para position of the aryl ring to anchor catalytically
active centers to silica supports,5b to organized macro-
molecules such as dendrimers,5c and to polymers,5d with
retention of catalytic activity. For the Kharasch addi-
tion reaction we have discovered that the catalytic cycle
involves a NiII/NiIII couple in which, remarkably, the
Ni-Cipso bond is not disrupted. The adaptability of this
ligand during the catalytic cycle is illustrated by model
nickel complexes in which the N-Ni-N angle needs
only to vary a little from 166.59(6)° in a square-planar
Ni(II) species6 to 152.0(2)° in a square-pyramidal com-
plex with a Ni(III) center.7 The present paper describes
the syntheses of some new ruthenium complexes with
the C6H3(CH2NMe2)2-2,6- ligand and gives crystal-
lographic data for four of these complexes in which acute
N-Ru-N angles demonstrate the flexible coordination
geometry of this aryldiamine ligand system. The prop-
erties of this 6-electron donor ligand are compared and
product is also obtained when 1 is reacted with [RuCl2-
(PPh3)3], but the yield is substantially lower. The iodide
analogue [Ru{C6H3(CH2NMe2)2-2,6}(I)(PPh3)], 2b, can
be obtained from 2a by a halide metathesis reaction
with KI in MeOH (Scheme 2). Complexes 2a ,b are
obtained, after crystallization from CH2Cl2/hexane solu-
tions, as blue, crystalline, air-sensitive solids which are
soluble in solvents such as dichloromethane and ben-
zene. Characteristic solution spectroscopic data for 2a
include a singlet 31P NMR resonance at 79.0 ppm
(CDCl3) and in the 1H NMR spectrum (CDCl3) two
singlets for the NMe2 groups and an AB pattern for the
methylene protons; i.e., the methyl groups and meth-
ylene protons are diastereotopic. Similar spectra were
obtained for the iodide complex 2b. In order to establish
the nuclearity of this type of complex and the stereo-
chemistry of the ligand array around ruthenium, an
X-ray structure determination of complex 2b was car-
ried out. Suitable crystals of 2b were grown from a
benzene solution layered with pentane. An ORTEP
drawing of the determined molecular structure (Figure
1) shows 2b to be a mononuclear, pentacoordinate
ruthenium(II) species. The metal coordination geometry
is best described as square-pyramidal with the aryl-
diamine ligand functioning as a N,C,N terdentate sys-
tem (N(1), C(1), and N(2)) that occupies three positions
in the basal plane of the pyramid; the N-Ru-N angle
is 147.59(7)°. The iodine atom occupies the other basal
position ( C(1)-Ru-I ) 160.44(6)°) and the PPh3 is
coordinated apically ( C(1)-Ru-P ) 92.19(6)°). The
nature of the ligands in 2b make this a 16-electron
species, and the square-pyramidal geometry found in
the solid state is consistent with the solution NMR data.
The potential of complexes of type [Ru{C6H3(CH2-
NMe2)2-2,6}X(PPh3)], 2, to provide routes to other
organometallic species of C6H3(CH2NMe2)2-2,6- has
been investigated by reaction with 2,2′:6′,2′′-terpyridine
(terpy). The reaction of terpy with 2a in MeOH affords
by a ligand substitution reaction a new ionic organoru-
thenium complex which was isolated and characterized
by elemental microanalysis and NMR data as [Ru-
{C6H3(CH2NMe2)2-2,6}(terpy)]Cl, 3, which contains no
PPh3 (Scheme 2). Complex 3 is a blue air-stable solid
which, in accord with its ionic nature, is soluble in water
and alcohols. The NMR data for 3 reveal a high degree
of symmetry within the complex cation; for example, in
its 1H NMR spectrum (CDCl3) the [C6H3(CH2NMe2)2-
2,6]- ligand system affords a singlet resonance for the
-
-
contrasted with those of classical C5H5 and C5Me5
anions, and its coordination behavior is found to show
-
parallels to that of C5Me5
.
Resu lts
Syn th esis of Ru th en iu m Com p lexes of [C6H3-
(CH2NMe2)2-2,6]-. The dimeric organolithium complex
[Li{C6H3(CH2NMe2)2-2,6}]2, 1,8 proves to be an excellent
reagent for the synthesis of a number of stable Ru(II)
species containing the C6H3(CH2NMe2)2-2,6- ligand. The
reaction of 1 with [RuCl2(PPh3)4] in THF affords a new
complex identified by elemental microanalysis and NMR
data as the ruthenium(II) species [Ru{C6H3(CH2NMe2)2-
2,6}Cl(PPh3)], 2a , in 60% yield (Scheme 2). The same
(5) (a) Grove, D. M.; van Koten, G.; Verschuuren, A. H. M. J . Mol.
Catal. 1988, 45, 169. Grove, D. M.; Verschuuren, A. H. M.; van Koten,
G.; van Beek, J . A. M. J . Organomet. Chem. 1989, 372, C1. van de
Kuil, L. A.; Luitjes, H.; Grove, D. M.; Zwikker, J . W.; van der Linden,
J . G. M.; Roelofsen, A. M.; J enneskens, L. W.; Drenth, W.; van Koten,
G. Organometallics 1994, 13, 468. (b) Wijkens, P.; Grove, D. M.; van
Koten, G. Unpublished results. (c) Knapen, J . W. J .; van der Made, A.
W.; de Wilde, J . C.; van Leeuwen, P. W. N. M.; Wijkens, P.; Grove, D.
M.; van Koten, G. Nature 1994, 372, 659. (d) van de Kuil, L. A.; Grove,
D. M.; Zwikker, J . W.; J enneskens, L. W.; Drenth, W.; van Koten, G.
Chem. Mater. 1994, 6, 675.
(6) Grove, D. M.; van Koten, G.; Ubbels, Zoet, R.; Spek, A. L.
Organometallics 1984, 3, 1003.
(7) Grove, D. M.; van Koten, G.; Mul, P.; Zoet, R.; van der Linden,
J . G. M.; Legters, J .; Schmitz, J . E. J .; Murral, N. W.; Welch, A. J .
Inorg. Chem. 1988, 27, 2466.
(8) J astrebski, J . T. B. H.; van Koten, G.; Konijn, M.; Stam, C. H.
J . Am. Chem. Soc. 1982, 104, 5490. van der Zeijden, A. A. H.; van
Koten, G.; Spek, A. L. Recl. Trav. Chim. Pays-Bas 1988, 107, 431.

Ruthenium(II) Aryldiamine Complexes
Organometallics, Vol. 15, No. 3, 1996 943
F igu r e 3. Thermal motion ellipsoid plot (50% probability
level) of 4. H atoms were omitted for clarity.
F igu r e 2. Thermal motion ellipsoid plot (50% probability
level) of 3. H atoms were omitted for clarity.
Sch em e 3. P r ep a r a tion of 4 a n d 5
four methylene protons, and a singlet resonance for the
methyl groups of the two NMe2 units. These data
suggest a simple octahedral geometry at the metal, with
both the N,C,N and terpyridine ligands coordinating
meridionally, making 3 an 18-electron complex. In
order to establish more precisely the ligand arrange-
ment in this complex, an X-ray structure determination
was carried out. Suitable crystals of 3 were grown by
slow evaporation of a CH2Cl2/toluene solution. An
ORTEP drawing of the determined molecular structure
of the cation of 3 is shown in Figure 2. The structure
determination confirms the meridional bonding of the
aryldiamine ligand ( N-Ru-N ) 156.2(2)°) and the
overall C2 symmetry inferred from the solution NMR
spectra. The proximity of the NMe2 groups to the
shielding π-systems of the terpy group accounts for the
high-field chemical shift of these protons in the 1H NMR
spectra of 1.25 ppm (CDCl3). We have briefly reported
this compound and its reaction with excess CuCl2 to give
a dimeric product elsewhere.9
To further develop non-phosphine-ruthenium chem-
istry, 1 equiv of polymeric [RuCl2(nbd)]n, (nbd ) nor-
bornadiene)] was reacted with 0.5 equiv of dimer
[Li{C6H3(CH2NMe2)2-2,6}]2, 1, to afford a new complex
4, whose elemental microanalysis and NMR data are
consistent with the formulation [Ru{C6H3(CH2NMe2)2-
2,6}Cl(nbd)], in 20-30% isolated yield; see Scheme 3.
Complex 4 is a yellow, air-stable, solid which is readily
and 13C NMR spectral data of 4 (CDCl3) are consistent
with the presence of a single mirror-type symmetry
plane that is perpendicular to the aryl ring and so
positioned that the metal center, the CH2 bridge of the
norbornadiene ligand, and the ipso and para carbons
of the aryl ring are also in this plane. As was also found
for 2, the methylene protons and methyl groups of each
CH2NMe2 group are diastereotopic. A single-crystal
X-ray structural analysis of 4, carried out to investigate
the geometry of the ligand array, shows this complex
to be a mononuclear species [Ru{C6H3(CH2NMe2)2-2,6}-
Cl(nbd)] with a hexacoordinate ruthenium(II) center
(see Figure 3). The ligand array of halide, η4-bonded
(bidentate) norbornadiene, and N,C,N-bonded C6H3(CH2-
NMe2)2-2,6- makes this an 18-electron species in which
the overall positioning of the ligands in the solid state
aggrees with the observed solution NMR data. A most
interesting and very evident aspect of the structure is
that the aryldiamine ligand has adopted a pseudofacial
N,C,N coordination mode, with a N-Ru-N angle that
is only 110.09(7)°. The chloride is positioned ap-
proximately trans to Cipso (C(1)). The metal coordination
geometry in this complex is best described as a bicapped
tetrahedron10 in which the centroids of the two coordi-
nated alkenes together with Cipso and Cl form a pseudot-
etrahedron, with the N-donor atoms of the aryldiamine
1
soluble in CH2Cl2 and slightly soluble in THF. The H
(9) Sutter, J .-P.; Grove, D. M.; Beley, M.; Collin, J .-P.; Veldman, N.;
Spek, A. L.; Sauvage, J .-P.; van Koten, G. Angew. Chem., Int. Ed. Engl.
1994, 33, 1282.
(10) Hoffmann, R.; Howell, J . M.; Rossi, A. R. J . Am. Chem. Soc.
1976, 98, 2484.
(11) Blosser, P. W.; Gallucci, J . C.; Wojcicki, A. Inorg. Chem. 1992,
31, 2376. Kraakman, M. J . A.; de Klerk-Engels, B.; de Lange, P. P.
M.; Vrieze, K.; Smeets, W. J . J .; Spek, A. L. Organometallics 1992, 11,
3774.
(12) Kraaijkamp, J . G.; van Koten, G.; de Booijs, J . L.; Ubbels, H.
C.; Stam, C. H. Organometallics 1983, 2, 1882. van Koten, G.;
Terheijden, J .; van Beek, J . A. M.; Wehman-Ooyevaar, I. C. M.; Muller,
F.; Stam, C. H. Organometallics 1990, 9, 903. Grove, D. M.; van Koten,
G.; Mul, W. P.; van der Zeijden, A. A. H.; Terheijden, J .; Zoutberg, M.
C.; Stam, C. H. Organometallics 1986, 5, 322. van der Zeijden, A. A.
H.; van Koten, G.; Luijik, R.; Vrieze, K.; Slob, C.; Krabbendam, H.;
Spek, A. L. Inorg. Chem. 1988, 27, 1014.
(13) de Koster, A.; Kanters, J . A.; Spek, A. L.; van der Zeijden, A.
A. H.; van Koten, G.; Vrieze K. Acta Crystallogr. 1985, C41, 893.
(14) Abbenhuis, H. C. L.; Feiken, N.; Grove, D. M.; J astrzebski, J .
T. B. H.; Kooijman, H.; van der Sluis, P.; Smeets, W. J . J .; Spek, A. L.;
van Koten, G. J . Am. Chem. Soc. 1992, 114, 9773. Abbenhuis, H. C.
L.; Rietveld, M. H. P.; Haarman, H. F.; Hogerhiede, M. P.; Spek, A.
L.; van Koten, G. Organometallics 1994, 13, 3259.

944 Organometallics, Vol. 15, No. 3, 1996
Sutter et al.
F igu r e 5. Edge-on view of the distorted aryl-ruthenium
interaction in 5.
Sch em e 4. Exa gger a ted Sch em a tic View of th e
Ar yl-Ru th en iu m In ter a ction a n d Distor ted
Ar om a tic Rin g in 2b, 4, a n d 5, w ith Ta bu la tion of
Releva n t An gles
F igu r e 4. Thermal motion ellipsoid plot (50% probability
level) of 5. H atoms were omitted for clarity.
capping two of its faces. A detailed comparative discus-
sion of this metal coordination geometry, which is
accompanied by aryl ring distortions, is presented below.
The bond lengths between ruthenium and the olefinic
carbons atoms are in the normal range for hexacoordi-
nate ruthenium norbornadiene complexes.
defined by the aryl ring. However, examination of the
structure of the 16-electron complex 2b shows that in
this complex the coordination of the N,C,N ligand is no
longer perfectly meridional, with the angle C(1)-Ru-I
) 160.44(6)°. In the norbornadiene complexes 4 and 5
this perturbation of the aryl-ruthenium geometry is
even more evident. In these species not only does the
metal atom lie significantly out of the Cipso sp2 hybrid-
ization plane but there are also appreciable distortions
from nonplanarity within the aromatic ring itself. The
aryl ring is bent into a shallow boat conformation, as
illustrated in Figure 5, with Cipso and the C atom para
to the metal center (C(1) and C(4), respectively) lying
above the mean plane defined by the four other aryl
carbon atoms (C(2)C(3)C(5)C(6)). Scheme 4 tabulates
the principle aryl distortions in 2b and 3-5 in terms of
the planes defined by C(2)C(3)C(5)C(6), C(1)C(2)C(6),
and C(3)C(4)C(5), together with a schematic view of the
aryl-ruthenium moiety perpendicular to the Ru-C(1)
bond. In all these complexes the C-C bond lengths are
within their normal ranges. Predictably, the strongest
puckering of the aryl ring is found for 5, where the
N-Ru-N′ angle is the smallest. The origin of these ring
distortions is readily found in the pseudofacial coordina-
tion of C6H3(CH2NMe2)2-2,6- to ruthenium whereby the
donor NMe2 units have to come far out of the aryl plane
and the C(methylene)-C(aryl) bonds are put under
tension. Consequently these bonds are pulled out of the
aryl plane and the geometric distortion this causes at
the sp2 aryl atom to which CH2NMe2 arms are attached
then perturbs the rest of the aryl framework.
Substitution of the Cl atom in [Ru{C6H3(CH2NMe2)2-
2,6}Cl(nbd)], 4, for the weakly nucleophilic trifluo-
romethanesulfonate anion (OSO2CF3-, triflate) was
investigated with the intention of generating a five-
coordinate complex cation [Ru{C6H3(CH2NMe2)2-2,6}-
(nbd)]+ whose chemical reactivity would be different
from that of neutral 4. The reaction of 4 with [AgSO3-
CF3] in the presence of excess SMe2 leads to quantitative
formation of AgCl and formation of a new air-stable
species 5, which could be isolated as yellow crystals in
good yield. Elemental microanalysis data were consis-
tent with the composition Ru{C6H3(CH2NMe2)2-2,6}-
1
(nbd)(SO3CF3) (Scheme 3). However, since the H and
13C NMR data for 5 (C6D6) are very similar to those of
neutral 4 and not consistent with an ionic composition,
a single-crystal X-ray structure determination of 5 was
undertaken. This study shows 5 to be the neutral
mononuclear complex [Ru{C6H3(CH2NMe2)2-2,6})(η1-
OSO2CF3)(nbd)] that is likewise a hexacoordinate, 18-
electron, ruthenium(II) species (Figure 4). The overall
bicapped tetrahedral structure is very similar to that
of 4, and as well as the bidentate bonding of norborna-
diene to the metal center there is again terdentate
N,C,N bonding of the C6H3(CH2NMe2)2-2,6- ligand in
a pseudofacial coordination mode; the N-Ru-N′ angle
of 109.35(6)° is slightly more acute than in 4. Interest-
ing is the fact that the sixth coordination site in 5,
pseudo-trans to Cipso, is occupied by an η1-OSO2CF3
anion with a Ru-O(1) distance of 2.2327(16) Å. Only a
limited number of ruthenium complexes with an η1-
OSO2CF3 ligand are known.11
Ar yl-Ru th en iu m In ter a ction in 2b a n d 3-5. The
most straightforward of the structures determined is
that of the octahedral terpyridine complex 3. The
C6H3(CH2NMe2)2-2,6- ligand is meridionally bonded (as
is the terpy ligand) giving rise to an unstrained aryl ring
which is not significantly distorted from planarity and
a ruthenium center which lies within the mean plane
Discu ssion
N,C,N F lexibility. In previous studies we have
usually found that square-planar and octahedral metal
complexes containing the terdentate bonded C6H3(CH2-
NMe2)2-2,6- ligand have the metal and the N,C,N′-
ligating atoms in one plane;12 the N-donor atoms are
then pseudo trans-positioned, and for PtII, PdII, PtIV, NiII,
and NiIII N-M-N angles of (160-165° are normal.1
In these systems the metal coordination geometry is not
optimal, but the formation of two five-membered chelate
(15) (a) Donkervoort, J . G.; J astrzebski; J . T. B. H; Boersma, J . H.;
Spek, A. L.; Kooijman, H.; van Koten, G. Chem. Eur. J ., in press. (b)-
Hogerheide, M. P; J astrzebski, J . T. B. H.; Boersma, J . H.; Kooijman,
H.; Spek, A. L.; van Koten, G. Manuscript in preparation.

Ruthenium(II) Aryldiamine Complexes
Organometallics, Vol. 15, No. 3, 1996 945
rings clearly compensates for the N-M-N angle of less
than 180°. Examples of nonplanar M(N,C,N) arrange-
ments are rare but include square-pyramidal paramag-
netic NiIII 6,7 and FeIII 13 species,7,13 where the N-M-N
angles are somewhat less at 152.0(6) and 142.98(6)°,
respectively. This situation is still not ideal but the
N-M-N angle is now fairly close to that found in
pyramidal complexes of Ni(II) and Fe(II) containing
monodentate ligands. What is evident from the present
study is that the C6H3(CH2NMe2)2-2,6- ligand can
achieve much smaller N-M-N angles of (110° (nor-
bornadiene complexes 4 and 5). This corroborates our
previous observation of an N-M-N angle of 118.63(14)°
in the tantalum alkylidene complex [Ta(Cl)2{C6H3(CH2-
NMe2)2-2,6}(CHtBu)].14 This flexibility of the N,C,N
terdentate coordination mode is far higher than we
originally anticipated. The pseudofacial coordination of
C6H3(CH2NMe2)2-2,6- in these complexes is accompa-
nied by a bicapped tetrahedral geometry at the metal
center. A bicapped tetrahedron is not a common ar-
rangement for a hexacoordinate metal complex, and it
is therefore significant that we have recently also
identified this arrangement in some Ta,14 Ti,15a and
Lu15b complexes of this aryldiamine.
away from the bulky apical PPh3 ligand. The result of
this arrangement is that the potential sixth coordination
site becomes sterically crowded by the NMe2 groups; i.e.
the terdentate ligand is acting as a very bulky ligand.
In contrast, in 4 and 5 (with pseudofacial coordination)
the aryldiamine acts as a much smaller ligand that
allows all three remaining sites on ruthenium to be
occupied. Thus it appears that the N,C,N ligand mark-
edly adjusts its effective steric bulk in accordance with
the demands of the other ligands present. This suggests
that it may be possible to tune its bulk by judicious
choice of ancilliary ligands. The flexibility shown by this
ligand in adopting several coordination geometries, as
well as its ability in adapting to the demands of the
metal center, make it ideal for the stabilization of
transient intermediates in organometallic transforma-
tions. The reaction of 2a with 2,2′:6′,2′′-terpyridine
(Scheme 2) to give 3, during which the aryldiamine
coordination geometry switches to a meridional one in
order to allow meridional η3-N,N′,N′′ coordination of the
incoming terpy illustrates the ready interconversion of
these two coordination modes.
Com p a r ison of {C6H3(CH2NMe2)2-2,6}- w ith th e
Cyclop en ta d ien yl a n d P en ta m eth ylcyclop en ta d i-
en yl Liga n d s. The cyclopentadienyl ligand (C5H5-, Cp)
and its permethylated derivative (C5Me5-, Cp*) are
usually encountered in transition metal complexes as
monoanionic 6-electron donors, occupying three facial
coordination sites at a metal center. Despite obvious
differences in symmetry, there exists in this sense a
formal relationship between these ligands and C6H3(CH2-
NMe2)2-2,6-, also a monoanionic 6-electron donor, when
it is N,C,N pseudofacially coordinated, as in the nor-
bornadiene complexes 4 and 5. This relationship ex-
presses itself practically in the existence of Cp and Cp*
complexes, namely [Ru(Cp)(cod)Cl]16 and [Ru(Cp*)-
(diene)Cl] (diene ) norbornadiene, cis,cis-1,5-cycloocta-
diene, etc.),17,18 which are stoichiometrically analogous
to 4 and 5. In ruthenium(II) complexes where phos-
phines exist in conjunction with the Cp* ligand, one or
two phosphines may coordinate to ruthenium, depend-
ing on the steric demands of the phosphine. Thus bulky
ligands like triisopropylphosphine and tricyclohex-
ylphosphine afford the mono(phosphine) 16-electron
Ru th en iu m Coor d in a tion Geom etr y: Electr on ic
a n d Ster ic F a ctor s. As shown above, pseudofacial
coordination of this ligand leads to distortions of the aryl
ring whose magnitude is directly related to the N-Ru-N
angle, and this is naturally a consequence of the overall
coordination geometry of the metal center. The struc-
tures of 2b (pseudomeridional coordination), 3 (meridi-
onal coordination), and 4 and 5 (pseudofacial coordina-
tion) show for the first time in a series of homometallic
complexes how the C6H3(CH2NMe2)2-2,6- ligand accom-
modates its coordination geometry in concert with the
steric and electronic requirements of other ligands. In
the bicapped tetrahedral coordination geometry of com-
plexes 4 and 5 (Figures 3 and 4), for example, the
geometry seems to be strongly influenced by steric
factors and the resulting structure is one in which
crowding between the aryldiamine ligand, in particular
the NMe2 groups, and the other ligands in the ruthe-
nium coordination sphere are minimized. On this basis
one could say that it is the demanding and inflexible
bidentate bonding of norbornadiene that forces the
aryldiamine ligand to adopt its pseudofacial coordina-
tion geometry. However, the situation is complicated
further not only by chelate ring strain and the related
energetics of aryl ring distortions but also by electronic
factors which tend to impose their preferred geometry
at the metal center. To try to evaluate which of these
factors dominate in producing particular C6H3(CH2-
NMe2)2-2,6- geometries, and in particular the occur-
rence of a bicapped tetrahedral geometry for certain
metal centers, we are now embarking on a series of
theoretical and modelling studies.
i
complexes [Ru(Cp*)(PR3)Cl] (R ) Pr, Cy), which are
deep blue in color.19 These species are directly related
to our new mono(triphenylphosphine) complex 2, which
is also deep blue. The color arises in each case from a
single absorption at 576 nm (ꢀ ) 1692 M-1 cm-1
;
[Ru(Cp*)(PiPr3)Cl]), 580 nm (ꢀ ) 1742 M-1 cm-1; [Ru-
(Cp*)(PCy3)Cl]), and 557 nm (ꢀ ) 1287 M-1 cm-1; 2a ).
Unfortunately, the UV/vis spectra cannot be fully
compared since for 2a the UV region is dominated by
strong absorptions between 230 and 340 nm, due to
triphenylphosphine and the aromatic aryldiamine ligand.
Perhaps significantly, an attempt to prepare the bis-
(triphenylphosphine) complex [Ru(Cp*)(PPh3)2Cl] failed.20
Coordination of a second triphenylphosphine to 2a does
not occur either (there is excess phosphine present
However, even at this stage we can identify one aspect
of the aryldiamine ligand that is likely to be important
and which is not encountered with many other ligand
systems, namely its variation in steric bulk as a function
of coordination mode. For example, in square-pyrami-
dal 2b, shown in Figure 1, it is evident that the
aryldiamine ligand occupies a large volume about the
metal center and the five-membered chelate rings are
puckered in such a way as to bring the methyl groups
(16) Trost, B. M.; Indolese, A. J . Am. Chem. Soc. 1993, 115, 4361.
(17) Fagan, P. J .; Mahoney, W. S.; Calabrese, J . C.; Williams, I. D.
Organometallics 1990, 9, 1843.
(18) Oshima, N.; Suzuki, H.; Moro-Oka, Y. Chem. Lett. 1984, 1161.
(19) Campion, B. K.; Heyn, R. H.; Tilley, T. D. J . Chem. Soc., Chem.
Commun. 1988, 278.
(20) Hallman, P. S.; Stephenson, T. A.; Wilkinson, G. Inorg. Synth.
1970, 12, 237.

946 Organometallics, Vol. 15, No. 3, 1996
Sutter et al.
Ta ble 1. Cr ysta llogr a p h ic Da ta for 2b a n d 3-5
complex
2b
3
4
5
Crystal Data
C27H30N5Ru‚Cl‚CH2Cl2
646.02
formula
Mr
C30H34IN2PRu
681.56
C20H27F3N2O3RuS
533.58
C19H27ClN2Ru
419.96
cryst system
space group
a, Å
b, Å
c, Å
monoclinic
C2/c (No. 15)
33.722(3)
10.1880(10)
15.778(2)
92.199(10)
5416.5(10)
1.672
orthorhombic
Fdd2 (No. 43)
28.5405(13)
32.042(2)
12.100(2)
orthorhombic
P212121 (No. 19)
9.7428(7)
12.0561(8)
18.1700(7)
orthorhombic
P212121 (No. 19)
10.0105(10)
12.4130(10)
14.023(2)
â, deg
V, Å3
11065.2(18)
1.551
2134.3(2)
1.660
1742.5(3)
1.601
D
calc, g cm-3
Z
8
16
4
4
F(000)
2720
17.7
0.50 × 0.20 × 0.25
5280
8.7
0.15 × 0.15 × 0.63
Data Collection
150
1088
8.6
0.13 × 0.50 × 0.50
864
10.4
µ, cm-1
cryst size, mm
0.40 × 0.40 × 0.40
T, K
150
150
295
θ
min, θmax, deg
1.21, 27.5
0.710 73 (mon)
0.54 + 0.35 tan θ
3.00, 4.00
27.9
1.9, 27.5
1.12, 27.5
0.710 73 (mon)
0.61 + 0.35 tan θ
3.00, 4.00
12.4
1.45, 27.5
0.710 73 (Zr)
0.54 + 0.35 tan θ
3.00, 5.00
66.9
λ(Mo KR), Å
∆ω, deg
0.710 73 (mon)
0.86 + 0.35 tan θ
2.73, 4.00
hor, ver apert, mm
X-ray exposure, h
ref reflcns
data set
tot. data
19.9
2,-4,1; 6,2,-4; 12,0,2 0,-2,-10; 14,0,-2; -2,-4,-4 -2,-4,-3; -1,-2,-5; -3,3,0 2,3,3; 3,2,-1; 1,5,2
-43:43, 0:13, -20:20 -36:37, -41:0, -15:0
13364
6219
-8:15, -12:12, -23:0
5464
4887
0:12, 0:16, -18:18
4874
3990
6645
3329
tot. unique data
obsd data
I > 2.5σ(I)
5696
4710
3810
I > 2.0σ(I)
2306
difabs corr range
0.903, 1.209
0.94, 1.100
0.933, 1.045
Refinement
no. of refined params
330
0.0230
0.0271
311
0.0515
297
0.0187
0.0261
233
0.0189
0.0194
final Ra
b
Rw
wR2c
0.0980
S
2.85
0.92
0.75
0.77
w-1 d
[σ2(F)]
[σ2(Fo2) + (0.0336P)2]
0.000, 0.001
-0.55, 0.79
[σ2(F) + 0.000605F2]
0.015, 0.24
-0.71, 0.99
[σ2(F)]
(∆/σ)av, (∆/σ)max
0.026, 0.606
0.036, 0.528
-0.49, 0.36
min and max resid density, e Å-3 -0.85, 0.67
a
b
d
R1 ) ∑||Fo| - |Fc||/∑|Fo|. Rw ) [∑[w(||Fo| - |Fc||)2]/∑[w(Fo2)]]1/2
.
c wR2 ) [∑[w(Fo2- Fc2)2]/∑[w(Fo2)2]]1/2
.
P ) (max(Fo2;0) + 2Fc2)/3.
during the preparation). However, with Cp*, the steri-
cally less demanding ligand trimethylphosphine affords
the bis(phosphine) complex [Ru(Cp*)(PMe3)2Cl],21 and
we are currently investigating the use of less bulky
phosphines to prepare analogous bis(phosphine) ruthe-
nium complexes with C6H3(CH2NMe2)2-2,6-. It should
be noted that, in ruthenium(II) phosphine complexes
with the Cp ligand, only coordinatively saturated 18-
electron complexes with two phosphines are known, e.g.
[Ru(Cp)(PR3)2Cl] (R ) Ph, Me).22 Compared to Cp, the
superior ability of the (C5Me5)- anion and C6H3(CH2-
NMe2)2-2,6- to stabilize unsaturated 16-electron com-
plexes may be attributed to both greater steric bulk and
better electron donor capabilities.
The similarity suggested here between Cp* and
C6H3(CH2NMe2)2-2,6- may be of use in developing
future chemistry of ruthenium complexes of the latter
ligand. We are now investigating not only the relative
importance of steric and electronic factors in such
complexes but also their reactivity in catalytic processes
where we have found complex 2b to be an effective
hydrogen transfer catalyst.23
Con clu sion
In this first investigation of the organoruthenium
chemistry of the C6H3(CH2NMe2)2-2,6- ligand system
we have found that it can exhibit considerable flexibility
in its coordination geometry. In terms of the complexes
we have isolated, analogy may be drawn between this
ligand and the classical ligand Cp*.
Exp er im en ta l Section
Gen er a l Com m en ts. All experiments were conducted
under a dry nitrogen atmosphere using standard Schlenk
techniques. Solvents were dried over appropriate materials
and distilled prior to use. Elemental analyses were performed
by Dornis und Kolbe, Mikroanalytisches Laboratorium (Mu¨l-
heim, Germany); 1H, 13C, and 31P NMR spectra were recorded
at 298 K on Bruker AC200 or AC300 spectrometers unless
otherwise stated. Starting materials [Li{C6H3(CH2NMe2)2-
2,6}]2, 1,24 [RuCl2(PPh3)4],25 and [RuCl2(nbd)]n26 were prepared
according to literature procedures. RuCl3‚3H2O was obtained
from Degussa.
(23) Karlen, T.; van Koten, G. Manuscript in preparation.
(24) J astrzebski, J . T. B. H.; van Koten, G.; Konijn, M.; Stam, C. H.
J . Am. Chem. Soc. 1982, 104, 5490.
(25) Hallman, P. S.; Stephenson, T. A.; Wilkinson, G. Inorg. Synth.
1970, 12, 237.
(26) Abel, E. W.; Bennett, M. A.; Wilkinson, G. J . Chem. Soc. 1959,
3178.
(21) Tilley, D. T.; Grubbs, R. H.; Bercaw, J . E. Organometallics 1984,
3, 274.
(22) Bruce, M. I.; Humphrey, M. G.; Swincer, A. G.; Wallis, R. C.
Aust. J . Chem. 1984, 37, 1747. Bruce, M. I.; Hameister, C.; Swincer,
A. G.; Wallis, R. C. Inorg. Synth. 1982, 21, 78.

Ruthenium(II) Aryldiamine Complexes
Organometallics, Vol. 15, No. 3, 1996 947
Ta ble 2. Selected Bon d Len gth s (Å) a n d Bon d An gles (d eg) for 2b a n d 3-5 (Esd ’s in P a r en th eses)
2b
3
4
5
2b
3
4
5
Bond Lengths
Ru-N(1)
Ru-N(2)
Ru-N(3)
Ru-N(4)
Ru-N(5)
Ru-I
2.2063(19) 2.199(7) 2.3381(19) 2.3171(17) Ru-O
2.2327(16)
2.1635(18) 2.192(7) 2.349(2)
2.2977(17) Ru-C(13)
Ru-C(14)
2.155(3)
2.150(3)
2.077(6)
2.007(6)
2.088(6)
2.165(2)
2.170(2)
Ru-C(15)
Ru-C(16)
2.137(3)
2.168(2)
2.8025(4)
2.1757(7)
Ru-C(17)
2.174(2)
2.153(2)
2.027(2)
Ru-P
Ru-C(18)
Ru-Cl
2.4747(8)
Ru-C(1)
1.967(2)
1.982(7)
2.060(2)
Bond Angles
N(1)-Ru-N(2)
N(1)-Ru-C(1)
N(2)-Ru-C(1)
C(1)-Ru-P
147.59(7) 156.2(2) 110.09(7) 109.35(6) C(1)-Ru-C(14)
122.81(9) 121.91(8)
85.15(7)
122.96(9)
79.50(8)
79.56(8)
92.19(6)
160.44(6)
105.07(6)
100.18(5)
93.51(5)
98.09(5)
77.9(3)
78.3(3)
74.15(8)
73.80(8)
74.91(7)
74.62(7)
C(1)-Ru-C(15)
C(1)-Ru-C(16)
C(1)-Ru-C(17)
C(1)-Ru-C(18)
C(1)-C(2)-C(3)
C(2)-C(3)-C(4)
C(3)-C(4)-C(5)
C(4)-C(5)-C(6)
C(1)-C(6)-C(5)
C(1)-C(2)-C(7)
C(1)-C(2)-C(10)
C(1)-C(6)-C(10)
C(1)-C(6)-C(7)
N(2)-C(7)-C(2)
N(2)-C(10)-C(2)
N(2)-C(7)-C(6)
N(1)-C(7)-C(6)
N(1)-C(10)-C(2)
N(1)-C(10)-C(6)
N(1)-Ru-Cl
86.02(9)
84.91(7)
C(1)-Ru-I
121.92(7)
120.69(18)
119.91(19)
119.56(18)
119.76(18)
120.33(18)
N(1)-Ru-P
120.1(2)
119.9(2)
120.9(2)
119.3(2)
120.0(2)
119.3(8)
120.5(9)
121.4(9)
119.1(8)
119.3(7)
113.3(8)
119.7(2)
120.4(2)
119.7(2)
120.1(2)
120.8(2)
N(2)-Ru-P
N(1)-Ru-I
N(2)-Ru-I
N(1)-Ru-N(3)
N(1)-Ru-N(4)
N(1)-Ru-N(5)
N(2)-Ru-N(3)
N(2)-Ru-N(4)
N(2)-Ru-N(5)
N(3)-Ru-N(4)
N(3)-Ru-N(5)
N(4)-Ru-N(5)
C(1)-Ru-N(3)
C(1)-Ru-N(4)
C(1)-Ru-N(5)
C(1)-Ru-Cl
94.2(3)
100.9(2)
89.4(2)
89.8(3)
102.9(2)
96.1(3)
78.6(2)
156.9(3)
78.3(2)
100.4(3)
178.4(3)
102.7(3)
113.80(18)
114.35(18)
109.11(18)
109.43(18)
116.07(19) 115.14(17)
115.65(19) 115.21(17)
112.4(6)
110.1(7)
107.69(18) 107.06(16)
107.19(18) 107.91(16)
109.4(7)
86.72(5)
86.70(5)
83.69(6)
83.95(6)
145.44(6)
85.72(9)
N(2)-Ru-Cl
C(1)-Ru-O(1)
C(1)-Ru-C(13)
142.24(6) N(1)-Ru-O(1)
N(2)-Ru-O(1)
Torsion Angles (deg)
C(1)-C(2)-C(3)-C(4) -0.4(3)
C(2)-C(3)-C(4)-C(5) 1.2(4)
C(3)-C(4)-C(5)-C(6) -0.5(4)
C(4)-C(5)-C(6)-C(1) -1.0(4)
C(6)-C(1)-C(2)-C(3) -1.1(3)
C(4)-C(3)-C(2)-C(7)
1.5(13)
-2.0(14) 5.4(4)
0.8(14)
0.8(13)
0.2(13)
175.4(9)
4.0(4)
-2.6(3)
-7.9(3)
6.6(3)
5.1(3)
14.0(3)
C(4)-C(3)-C(2)-C(10) -178.9(2)
C(6)-C(1)-C(2)-C(10) 179.48(18)
C(4)-C(5)-C(6)-C(7) 179.7(2)
C(4)-C(5)-C(6)-C(10)
C(2)-C(1)-C(6)-C(7) -178.8(2)
C(2)-C(1)-C(6)-C(10)
163.6(2)
167.0(3)
-167.19(18)
3.2(2)
-164.93(19)
-6.3(4)
-2.3(4)
-12.3(4)
-176.2(9)
-158.5(2) 155.66(18)
156.1(2)
176.1(8)
2
Syn th esis of [Ru Cl{C6H3(CH2NMe2)2-2,6}(P P h 3)] (2a ).
A solution of [Li{C6H3(CH2NMe2)2-2,6}]2, 1 (0.86 g, 2.17 mmol),
in THF (30 mL) was added dropwise to a suspension of [RuCl2-
(PPh3)4] (5.23 g, 4.28 mmol) in THF (60 mL). After 1 h the
solvent was removed in vacuo from the deep blue reaction
mixture and the residue washed with a Et2O/hexane (2:1)
mixture (100 mL). The remaining blue solid was extracted
with CH2Cl2. After the solution was concentrated and layered
with hexane, complex 2a was obtained as a deep blue micro-
crystalline solid (1.52 g, 60%).
and 2.49 (AB pattern, 4 H, J HH ) 13.9 Hz, CH2N), 2.13 and
2.03 (2 s, 12 H, NMe2). 13C NMR (CDCl3, 50 MHz): δ (ppm)
2
1
187.2 (d, J PC ) 14 Hz, C ipso), 148.6 (C ortho), 136.5 (d, J PC
) 47 Hz, PPh3), 134.6 (d, 2J PC ) 10 Hz, PPh3), 128.8 (d, 4J PC
)
3
2 Hz, PPh3), 127.1 (d, J PC ) 10 Hz, PPh3), 120.3 (C para),
120.2 (C meta), 74.0 (CH2N), 53.7 and 48.5 (NMe2). 31P NMR
(CDCl3, 81 MHz): δ (ppm) 89.0 (s, PPh3). Anal. Calcd for
C
30H34N2PIRu‚0.25C6H6: C, 55.60; H, 5.08; N, 4.03. Found:
C, 54.52; H, 5.08; N, 4.03.
Syn th esis of [Ru {C6H3(CH2NMe2)2-2,6}(ter p y)]Cl (3). A
solution of 2a (1.30 g, 2.20 mmol) and 2,2′:6′,2′′-terpyridine
(0.52 g, 2.20 mmol) in MeOH (40 mL) was heated at reflux for
3 h. After removal of the solvent in vacuo, the residue was
dissolved in CH2Cl2 (10 mL) and toluene (60 mL) was added.
The blue precipitate was filtered off, washed with Et2O, and
dried in vacuo to yield 3 (1.14 g, 92%). Analytically pure
crystals of 3 were obtained by slow concentration of a CH2-
Cl2/toluene solution.
1H NMR (C6D6, 300 MHz): δ (ppm) 7.80 (m, 6 H, Ar H),
3
6.96 (m, 10 H, Ar H), 6.83 (d, 2 H, J HH ) 7.3 Hz, Ar H), 2.54
2
and 2.48 (AB pattern, 4 H, J HH ) 13.8 Hz, CH2N), 2.18 and
2.01 (2 s, 12 H, NMe2). 13C NMR (CDCl3, 50 MHz): δ (ppm)
2
1
185.8 (d, J PC ) 15 Hz, C ipso), 148.8 (C ortho), 136.8 (d, J PC
) 46 Hz, PPh3), 134.5 (d, 2J PC ) 10 Hz, PPh3), 128.8 (d, 4J PC
2 Hz, PPh3), 127.3 (d, J PC ) 10 Hz, PPh3), 120.0 (C para),
119.6 (C meta), 74.3 (CH2N), 52.4 and 48.6 (NMe2). 31P NMR
(CDCl3, 81 MHz): δ (ppm) 91.1 (s, PPh3). Anal. Calcd for
)
3
1H NMR (CDCl3, 300 MHz): δ (ppm) 8.99 (d, 2 H, J HH
)
3
3
C
30H34N2PClRu: C, 61.06; H, 5.81; N, 4.75. Found: C, 60.8;
8.0 Hz, Ar H), 8.85 (d, 2 H, J HH ) 8.0 Hz, Ar H), 8.17 (d, 2 H,
3J HH ) 5.4 Hz, Ar H), 8.11 (t, 1 H, J HH ) 8.0 Hz, Ar H), 7.98
3
H, 5.8; N, 4.8.
3
Syn th esis of [Ru I{C6H3(CH2NMe2)2-2,6}(P P h 3)] (2b). To
solution of 2a (0.50 g, 8.5 mmol) in methanol (30 mL) was
added KI (0.99 g, 59.5 mmol) and the resulting solution stirred
for 5 h. The solvent was removed in vacuo and the residue
extracted with benzene. The benzene solution was concen-
trated to 5 mL and hexane added to induce precipitation. The
blue solid was collected and dried in vacuo (0.463 g, 68%).
Analytically pure samples were obtained by slow evaporation
of a benzene solution and included 0.25 C6H6.
(t, 2 H, J HH ) 7.8 Hz, Ar), 7.39 (m, 2 H, Ar), 7.26 (d, 2 H, Ar,
3J HH ) 7.4 Hz), 7.03 (t, 1 H, Ar), 3.64 (s, 4 H, CH2N), 1.22 (s,
12 H, NMe2). 13C (CDCl3, 75 MHz): δ (ppm) 220.2, 160.3,
154.2, 151.9, 141.9, 134.9, 129.4, 126.3, 124.0, 122.5, 120.7,
120.4, 74.8 and 51.7. Anal. Calcd for [C27H30N5ClRu + CH2-
Cl2]: C, 52.06; H, 4.99; N, 10.84. Found: C, 54.78; H, 5.71;
N, 11.37.
Syn th esis of [Ru Cl{C6H3(CH2NMe2)2-2,6}(C7H8)] (4). A
suspension of [RuCl2(nbd)]n (1.80 g, 6.8 mmol) and [Li-
{C6H3(CH2NMe2)2-2,6}]2, 1 (2.86 g, 3.6 mmol), in THF (60 mL)
was stirred at room temperature for 24 h. After removal of
1H NMR (C6D6, 200 MHz): δ (ppm) 7.78 (m, 6 H, Ar H),
3
6.91 (m, 10 H, Ar H), 6.75 (d, 2 H, J HH ) 7.3 Hz, Ar H), 2.69

948 Organometallics, Vol. 15, No. 3, 1996
Sutter et al.
the solvent in vacuo, the residue was washed with Et2O and
then extracted with CH2Cl2 (2 × 30 mL). The solvent was
removed to leave a yellow-brown solid. This residue was
stirred with THF (15 mL) and then left to stand at -30 °C for
18 h. The yellow solid 4 was collected and dried in vacuo
(0.855 g, 30%). An analytically pure sample was crystallized
from CH2Cl2.
by full-matrix least-squares techniques (SHELXL-9333) for 3;
no observance criterion was applied during refinement. Non-
hydrogen atoms were refined with anisotropic thermal pa-
rameters. Hydrogen atoms of 2b, 4, and 5 were included in
the refinement on calculated positions (C-H ) 0.98 Å) riding
on their carrier atoms, except for the hydrogens on C(13),
C(14), C(16), and C(17) (4) and on C(14), C(15), C(17), and
C(18) (5) of the norbornadiene, which were located on a
difference Fourier map and subsequently included in the
refinement. The hydrogen atoms of 3 were refined with a fixed
isotropic thermal parameter related to the value of the
equivalent isotropic thermal parameter of their carrier atoms,
by a factor of 1.5 for the methyl and 1.2 for the other hydrogen
atoms, respectively. Hydrogen atoms of 2b and 4 were refined
with one overall isotropic thermal parameters of 0.0276(13)
and 0.0441(15) Å2, respectively. Hydrogen atoms of 5 were
refined with two overall isotropic thermal parameters of
0.0269(17) and 0.0318(19) Å2 for the methylenic and the
remaining atoms, respectively. The refinement of 2b included
an empirical absorption correction parameter (0.00018(1));29
one reflection was omitted in view of experimental errors.
Weights were introduced in the final refinement cycles.
1H NMR (CDCl3, 300 MHz): δ (ppm) 6.97 (s, 3 H, Ar H),
2
3.98 and 2.92 (2d, 4 H, J HH ) 14.0 Hz, CH2N), 3.87 and 3.46
(2m, 4 H, HCd), 3.55 and 3.30 (2 br s, 2 H, CH), 1.99 and 1.95
(2 s, 12 H, NMe2), 1.24 (m, 2 H, CH2). 13C NMR (CDCl3, 50
MHz): δ (ppm) 178.5 (C ipso), 146.0 (C ortho), 122.5 (C para),
122.2 (C meta), 71.6 (CH2N), 57.1 (CH2), 54.7 and 45.0 (HCd),
49.8 and 48.2 (NMe2), 49.4 and 47.0 (CH). Anal. Calcd for
[C19H27N2ClRu + 0.25CH2Cl2]: C, 52.40; H, 6.28; N, 6.35.
Found: C, 52.40; H, 6.24; N, 6.40.
Syn th esis of [Ru (SO3CF 3){C6H3(CH2NMe2)2-2,6)(C7H8)]
(5). AgSO3CF3‚C6H6 (0.27 g, 0.80 mmol) was added to a
solution of 3 (0.31 g, 0.73 mmol) in CH2Cl2 (15 mL) and SMe2
(0.2 mL). After 20 min the reaction mixture was centrifuged
and the yellow supernatant removed and evaporated to
dryness. The residue was extracted with Et2O (3 × 20 mL)
and the resulting solution concentrated to approximately 15
mL and layered with hexane to yield 3 as yellow crystals (0.21
g, 53%).
The correct enantiomorphic structures were determined for
4 and 5. Final refinements of 4 and 5 were performed in their
absolute structure, giving the lowest R-values (Flack param-
eters -0.05(3), -0.02(3)35).
1H NMR (C6D6, 300 MHz): δ (ppm) 6.89 (t, 1 H, 3J HH ) 7.3,
3
Ar H), 6.66 (d, 2 H, J HH ) 7.3 Hz, Ar H), 4.39 and 3.17 (2 m,
The structure of 3 contains two CH2Cl2 molecules disordered
over an inversion center. No satisfactory solvent model could
be refined. The SQUEEZE36 procedure from PLATON34 was
used to take this electron density into account. Neutral atom
scattering factors taken from Cromer and Mann37 and anoma-
lous dispersion corrections from Cromer and Liberman38 were
used for 2b, 4, and 5. For 3 neutral atom scattering factors
and anomalous dispersion corrections were taken from ref 39.
Geometrical calculations and illustrations were performed with
PLATON;34 all calculations were performed on a DECstation
5000 cluster.
4 H, dCH), 4.04 and 2.90 (2 br s, 2 H, CH), 3.20 and 2.17 (2
2
d, 4 H, J HH ) 14.3, CH2N), 1.59 and 1.58 (2 s, 12 H, NMe2),
3
1.21 (t, 2 H, J HH ) 1.4, CH2). 13C (C6D6, 75 MHz): δ (ppm)
173.4, 145.5, 123.2, 122.6, 70.5, 59.1, 58.3, 50.9, 50.7, 49.9, 48.5,
and 47.3. Anal. Calcd for C20H27F3N2O3RuS: C, 45.04; H,
5.06; N, 5.25. Found: C, 44.92; H, 5.10; N, 5.29.
X-r a y Str u ctu r e Deter m in a tion of 2b a n d 3-5. Suitable
crystals for X-ray structure determination were glued on a
Lindemann glass capillary and transferred into the cold
nitrogen stream on an Enraf-Nonius CAD4-Turbo diffracto-
meter with rotating anode for 2b, 3, and 4 and on an Enraf-
Nonius sealed-tube CAD4 for 5. Accurate unit-cell parameters
and an orientation matrix were determined by least-squares
refinement of 25 reflections (set4) in the ranges 13.5° < θ <
16.1° for 4 and 11.5° < θ < 14.1° for the other compounds.
Reduced-cell calculations did not indicate higher lattice sym-
metry.27
Ack n ow led gm en t. This work was supported in part
(A.L.S., W.J .J .S., and N.V.) by the Netherlands Founda-
tion for Chemical Research (SON) with financial aid
from the Netherlands Organization for Scientific Re-
search (NWO). The stay of J .P.S. at the Debye Institute
was made possible through a grant from the European
Community (Scheme Contract No. SCI-0319-C(GDF)).
This study is part of a COST-D4 approved program.
Crystal data and details on data collection and refinement
of 2b and 3-5 are given in Table 1. Data were collected in
the ω/2θ scan mode. Data were corrected for Lp effects and
for the linear decay of the reference reflections (0%, 8%, 2%,
and 3%, respectively). Standard deviations of the intensities
are based on counting statistics,28 except for 3. For 2b, 4, and
5 an empirical absorption/extinction correction was applied
(DIFABS29). The structures 2b, 4, and 5 were solved by
automated Patterson methods and subsequent difference
Su p p or tin g In for m a tion Ava ila ble: Tables listing fur-
ther details of the structure determinations, atomic coordi-
nates, bond lengths and angles, and thermal parameters for
2b and 3-5 (39 pages). Ordering information is given on any
current masthead page.
Fourier techniques (DIRDIF-9230), and
3 was solved by
automated direct methods (SHELXS86).31 For 2b, 4, and 5
refinement on F was carried out by full-matrix least-squares
techniques (SHELX7632). Refinement on F2 was carried out
OM950700Q
(32) Sheldrick, G. M. SHELX76 Program for crystal structure
refinement, University of Cambridge, England, 1976.
(33) Sheldrick, G. M. SHELXL-93 Program for crystal structure
refinement, University of Go¨ttingen, Germany, 1993.
(34) Spek, A. L. Acta Crystallogr. 1990, A46, C34.
(35) Flack, H. D. Acta Crystallogr. 1983, A39, 876.
(36) Spek, A. L. A. Chem. Abstr. 1994, 22, 66.
(37) Cromer, D. T.; Mann, J . B. Acta Crystallogr. 1968, A24, 321.
(38) Cromer, D. T.; Liberman, D. J . Chem. Phys. 1970, 53, 1891.
(39) Wilson, A. J . C., Ed. International Tables for Crystallography;
Kluwer Academic Publishers: Dordrecht, The Netherlands, 1992; Vol.
C.
(27) Spek, A. L. J . Appl. Crystallogr. 1988, 21, 578.
(28) McCandlish, L. E.; Stout, G. H.; Andrews, L. C. Acta Crystallogr.
1975, A31, 245.
(29) Walker, N.; Stuart, D. Acta Crystallogr. 1983, A39, 158.
(30) Beurskens, P. T.; Admiraal, G.; Beurskens, G.; Bosman, W. P.;
Garc´ıa-Granda, S.; Gould, R. O.; Smits, J . M. M.; Smykalla, C. The
DIRDIF program system, Technical report of the Crystallography
Laboratory, University of Nijmegen, The Netherlands, 1992.
(31) Sheldrick, G. M. SHELXS86 Program for crystal structure
determination, University of Go¨ttingen, Germany, 1986.