Oxovanadium(IV) complexes as molecular catalysts in epoxidation: Simple access to pyridylalkoxide derivatives

Article abstract of DOI:10.1016/j.jorganchem.2005.11.034

Reaction of bis(aryl)-2-pyridylmethanol ligands (1a-7a) with VO(SO₄) · 5H₂O results in the formation of metal-oxo complexes [VO(N-O)₂] (1-7), with N-O = bis(aryl)-2-pyridylmethanol. A molecular structure of (4) has been de

Full text of DOI:10.1016/j.jorganchem.2005.11.034

Journal of Organometallic Chemistry 691 (2006) 2291–2296
www.elsevier.com/locate/jorganchem
Oxovanadium(IV) complexes as molecular catalysts in
epoxidation: Simple access to pyridylalkoxide derivatives
a
b
c
d
Gerhard M. Lobmaier , Harald Trauthwein , Guido D. Frey , Bernd Scharbert ,
c
c,
*
Eberhardt Herdtweck , Wolfgang A. Herrmann
a
Cognis Deutschland GmbH and Co. KG, Robert-Hausen-Strasse 1, D-89257 Illertissen, Germany
b
Degussa AG, Rodenbacher Chaussee 4, D-63457 Hanau-Wolfgang, Germany
Department Chemie, Lehrstuhl fu¨r Anorganische Chemie, Technische Universita¨t Mu¨nchen, Lichtenbergstraße 4, D-85747 Garching, Germany
c
d
Celanese Chemicals and Emulsions, Industriepark Ho¨chst, D-65926 Frankfurt/Main, Germany
Received 28 September 2005; received in revised form 10 November 2005; accepted 10 November 2005
Available online 28 December 2005
Abstract
Reaction of bis(aryl)-2-pyridylmethanol ligands (1a–7a) with VO(SO4) Æ 5H2O results in the formation of metal-oxo complexes
[VO(N-O)2] (1–7), with N-O = bis(aryl)-2-pyridylmethanol. A molecular structure of (4) has been determined by single crystals X-ray
diffraction study, which showed the expected square planar pyramidal geometry with the pyridine ring nitrogens in trans-position to each
other. The metal-oxo complexes (1–4,6,7) demonstrated the ability to catalyse epoxidation reactions of alkenes with molecular oxygen.
ꢀ 2005 Elsevier B.V. All rights reserved.
Keywords: Epoxidation; Metal oxides; Pyridyl alcohols; Vanadium
1. Introduction
that these ligands are perfectly stable in oxidation catalysis
with dioxomolybdenum(VI) complexes [7,8].
An application of oxovanadium(IV) compounds as oxi-
dation catalysts was first discovered by Sharpless in the
case of the regioselective epoxidation of allylic alcohols
[1]. Although these oxovanadium(IV) complexes were stud-
ied intensively with tert-butylhydrogenperoxide as oxidant
[2–4], these complexes have – with one exception: VO-
(acac)2 (8) – never been employed in oxidation catalysis
with molecular oxygen [5]. To investigate the potential of
these oxovanadium(IV) compounds in epoxidation cataly-
sis with molecular oxygen, the class of vanadium com-
plexes with bidentate N,O-ligands was synthesized [6].
Pyridyl alcohols, which consist of an aliphatic alkoxy func-
tion and an aromatic nitrogen donor atom, were used as
N,O-ligands for the syntheses, because it has been shown,
2. Results and Discussion
The new oxovanadium(IV)-complexes build up a big
variety of vanadium(IV)-complexes with a bidentate N,O-
ligand, which consist of an aliphatic hydroxy function com-
bined with a nitrogen-donor of a pyridine ring and two
phenyl groups at the backbone, bound to a (VO)2+-unit.
The used ligands were made by nucleophilic attack of 2-
lithiumpyridine on various aromatic ketones [9,10]. After
hydrolisation the prepared ligands were received pure and
in high yields.
The new oxovanadium(IV) catalysts 1–7 were synthe-
sized by a simple ligand exchange reaction of the sulphate
counter ion of the starting reagent VO(SO4) Æ 5H2O with
two equivalents of various pyridyl alcohols 1a–7a (Scheme
1). To deprotonate each equivalent of the chelating alcohol
sodium acetate was used. The driving force of this reaction
*
Corresponding author. Tel.: +49 89 289 13080; fax: +49 89 289 13473.
E-mail addresses: guido.frey@ch.tum.de (G.D. Frey), lit@arthur.
anorg.chemie.tu-muenchen.de (W.A. Herrmann).
0022-328X/$ - see front matter ꢀ 2005 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2005.11.034

2292
G.M. Lobmaier et al. / Journal of Organometallic Chemistry 691 (2006) 2291–2296
N
N
CH3CO2Na
VO(SO4) · 5 H2O + 2
O V
EtOH, reflux
R
R
R
R
HO
O
2
1a - 7a
1 - 7
1a R = C6H5
2a R = p-(t-butyl)-C6H4
3a R = p-F-C6H4
4a R R = C12H8
5a R = m-CF3-C6H4
6a R = p-Cl-C6H4
7a R = p-(OMe)-C6H4
Fig. 2. ESR spectra of complex 2 at 133 K.
Scheme 1. Synthesis of the complexes 1–7.
985 cmꢀ1) [6,11]. Additionally the aromatic stretching fre-
quencies of the pyridine ring indicate the complexation of
the oxovanadium-fragment by the ligands. The elemental
analyses clearly prove the existence of the resulting com-
plexes. Since vanadium(IV) complexes are known to be
paramagnetic systems, ESR methods are applied to prove
this. At room temperature, the ESR spectrum of 2 clearly
shows 8 lines, as expected for an I = 7/2 nucleus (Fig. 1).
The low temperature (133 K) ESR spectrum of 2 depicts
the anisotropic behaviour, as published by Attanasio
et al. for oxovanadium(IV) salen complexes (Fig. 2) [12].
In the case of 1–5 a magnetic moment of about 1.8 Bohr
magnetons was detected in accordance to published data
[13].
Suitable single crystals of the fluorenyl-derivative 4 for
X-ray diffraction study were grown from a dichlorometh-
ane/n-hexane mixture (Fig. 3).
The structure of complex 4 can be described as a square
planar pyramid. The nitrogen atoms in the pyridine rings
of the ligands are positioned trans to each other. This is
Fig. 1. ESR spectra of complex 2 at 293 K.
is the chelating effect of the two bidentate N,O-ligands. The
same reactions were carried out with vanadium acetylacet-
onate as starting material, but in this case the yields were
lower in comparison to the method described above.
The characterization of 1–7 is based on infrared spec-
troscopy. The characteristic oxovanadium stretching fre-
quency was detected in the range between 958 and
982 cmꢀ1, which is in accordance to the literature (970–
Fig. 3. ORTEP style plot [14f] of the solid state structure of complex 4. Thermal ellipsoids are drawn at the 50% probability level. The hydrogen atoms are
˚
omitted for clarity. Selected bond lengths [A] and bond angles [ꢁ]: V–O 1.609(3), V–O8 1.885(2), V–O28 1.893(2), V–N1 2.090(3), V–N21 2.097(4), O8–C7
1.411(4), O28–C27 1.397(4); O–V–O8 114.7(1), O–V–O28 114.3(1), O–V–N1 101.9(1), O–V–N21 104.3(1), O8–V–O28 131.0(1), O8–V–N1 79.22(9), O8–V–
N21 88.9(1), O28–V–N1 90.61(9), O28–V–N21 79.63(9), N1–V–N21 153.8(1), V–O8–C7 119.1(2), V–O28–C27 119.8(2).

G.M. Lobmaier et al. / Journal of Organometallic Chemistry 691 (2006) 2291–2296
2293
in contrast to the structures of oxovanadium(IV) salen
complexes, in which the nitrogen atoms are forced to coor-
dinate cis to the vanadium center. Especially the geometry
of the (trans-O)2(trans-N)2-V@O core is in accordance to
those found in C18H20N2O5V [15] and C18H16N2O3V [16].
The catalytical conversion of geraniole to the corre-
sponding epoxide was also possible (see Fig. 5). A regiose-
lectivity of >99% corresponding to allylic double bonds
was detected for the complexes 1–4, 6 and 7 with turnover
numbers (TONꢀs) of 100–400 and turnover frequencies
(TOF) of about 100 [hꢀ1 (average over the first 2 h)].
˚
The V@O bond distance of 1.609(3) A is typical for a five
coordinated vanadyl species [6,17].
For a catalytic application of these complexes it is
important that no possibility is given for a solvent molecule
to coordinate to the vanadium center. In this case a solvent
molecule could block the sixth co-ordination position and
disfavour the interaction with an oxidizing agent.
If complexes 1–4, 6 and 7 are used to change the product
distribution of the autoxidation reaction with 1-octene and
molecular oxygen, we found a selectivity of ꢁ30% based on
the epoxide (1, 33; 2, 29; 3, 27; 4, 30; 6, 27; 7, 26% product
selectivity). This is a slight improvement in selectivity com-
pared to the autoxidation data without any catalyst (23%).
The corresponding conversion curves are depicted in
(Fig. 4).
3. Conclusion
The class of oxo-vandium(IV) compounds with aliphatic
pyridyl alcohols can be synthesized easily via the vanadium
sulphate route. A single crystal X-ray structure determina-
tion shows a square-planar pyramidal co-ordination sphere
of the central vanadium atom. Contrary to the effects
known for dioxomolybdenum(VI) complexes with the
described pyridyl alcohols, the oxovanadium(IV) com-
plexes feature only slight improvement in catalytic selectiv-
ity when terminal alkenes are oxidized with molecular
oxygen. Further investigations are in progress to learn
more about the catalytic potential of these complexes on
various substrates.
4. Experimental
4.1. General comments
The ligands 1a, 4a, 6a and 7a [9], 2a [10,20], and ligand
5a [18] were prepared according to the literature. All reac-
tions were carried out under an argon atmosphere using
standard Schlenk techniques. Solvents were dried over acti-
vated molecular sieves and refluxed over appropriate dry-
1
ing agents under argon. H and 13C NMR spectra were
recorded on a JEOL-JMX-GX 270 or 400 MHz spectrom-
eter at room temperature and referenced to the residual 1H
and 13C signals of the solvents. NMR multiplicities are
abbreviated as follows: s, singlet; d, doublet; t, triplet; m,
multiplet. Coupling constants J are given in Hz. Elemental
analyses were carried out by the Microanalytical Labora-
Fig. 4. Diagram of the conversion of oxygen [in ml] vs. reaction time (t) of
the epoxidation reaction of 1-octene at 100 ꢁC. Complex 8 [bis(acetyl-
acetonato)oxovanadium(IV)] was used for comparison.
tory at the TU Munchen. Mass spectra were performed
¨
at the TU Munchen Mass Spectrometry Laboratory on a
¨
Finnigan MAT 90 (EI) or a Varian MAT 311a (CI) instru-
ment. IR spectra were recorded on a Perkin–Elmer 1650
FT-IR spectrophotometer using KBr discs. GC–MS spec-
tra were measured on a Hewlett–Packard gas chromato-
graph HP 5890A equipped with a mass selective detector
HP 5970 B. To measure the magnetic moments via para-
magnetic proton NMR, a method described by Evans
was used [19].
4.2. Preparation of bis(4-fluorophenyl)-2-pyridylmethanol
(3a)
Bis(4-fluorophenyl)-2-pyridylmethanol was synthesized
by the published procedure [20]. To a ꢀ78 ꢁC kept diethyl
ether solution (200 ml) 80.0 ml BuLi (1.6 M in n-hexane)
was added over 10 min. 11.5 ml (0.123 mol) of 2-bromo-
pyridine dissolved in 25 ml diethyl ether was added over
Fig. 5. Diagram of the conversion of geraniole [in %] vs. reaction time (t)
with different concentration of catalyst 6 at 50 ꢁC. 50 mmol geraniole,
50 mmol of a tert-butylhydrogenperoxide/n-decane solution, x mol%
catalyst, T = 50 ꢁC.

2294
G.M. Lobmaier et al. / Journal of Organometallic Chemistry 691 (2006) 2291–2296
10 min. The reaction was left stirring below ꢀ40 ꢁC for 2 h
after which 0.123 mol of 4,40-di-fluorobenzophenone dis-
solved in 30 ml diethyl ether was added slowly. The result-
ing solution was stirred for 1 h at ꢀ40 ꢁC and overnight at
room temperature. Hydrolysis was achieved using 50 ml of
a saturated NH4Cl solution. After evaporation of the ether
phase, the resulting white solid was washed with methanol
and recrystallized from hot methanol, giving 27.3 g (75%)
4.3.3. Bis{N,O-[1,1-di(4-fluorophenyl)-1-(20- pyridyl)-
methanolato]}oxovanadium(IV) (3)
Yield: 2.33 g (71%). Anal. Calc. for C36H24F4N2O3V
(659.52): C, 65.56; H, 3.67; F, 11.52; N, 4.25; O, 7.28; V,
7.72. Found: C, 65.7; H, 3.9; F, 11.2; N, 4.2; O, 7.3; V,
7.2%. CI-MS: m/z (%) = 659 (22, [M+]), 563 (18,
[M+ꢀ(C6H4+F)]), 362 (100). IR (KBr, cmꢀ1): m = 3025
(C–H, m), 1603 (C@N, s), 1504 (C–C, s), 1472 (C–C, m),
968 (V@O, s). leff (293 K) = 1.81 B.M.
of the product.
0
1H NMR (400 MHz, CDCl3): d = 8.57 (1H (H6 ), d,
0
3
3
3
JH6 ,H5 = 4 Hz), 7.63 (1H (H4 ), dd, JH4 ,H3 = 8 Hz,
4.3.4. Bis{N,O-[9-(20-pyridyl)fluoren-9-olato]}-
oxovanadium(IV) (4)
0
0
0
0
0
JH4 ,H5 = 8 Hz), 7.33 (1H (H3 ), d, JH3 ,H4 = 8 Hz), 7.25
3
0
0
0
0
0
(1H (H5 ), dd,
JH5 ,H6 = 4 Hz, JH5 ,H4 = 8 Hz), 7.24
Yield: 2.21 g (76%). Anal. Calc. for C36H24N2O3V Æ H2O
(601.54): C, 71.88; H, 4.36; N, 4.66; O, 10.64; V, 8.47.
Found: C, 71.2; H, 4.9; N, 4.9; O, 11.7; V, 8.4%. CI-MS:
m/z (%) = 583 (45, [M+]), 324 (100). IR (KBr, cmꢀ1):
m = 3034 (C–H, m), 1602 (C–N, m), 1473 (C–C, s), 1437
(C–C, s), 969 (V@O, s). leff (293 K) = 1.84 B.M.
3
3
0
0
0
0
00 00 000 000
(4H(H2 ,6 ,2 ,6000), dd, 3JHH = 8 Hz,3JFH = 5 Hz), 7.02
00 00 000
(4H(H3 ,5 ,3 ,5 ), dd, JHH = 8 Hz,3JFH = 8 Hz), 6.22 (1H,
3
s, OH). 13C{1H} NMR (100.5 MHz, CDCl3): d0= 162.8
0
0 0 0 0 0
(C2 ),000161.9 (C4 ,4 , d, JFC = 246 Hz), 147.9 (C6 ), 141.8
1
00
0
0
0
000 000
(C1 ,1 , d,1JFC = 21 Hz), 136.6 (C4 ), 129.5 (C2 ,6 ,2 ,6 , d,
0 0 0 0 0 0 0,50 0 0
1
1JFC = 8 Hz), 114.8 (C3 ,5 ,3
, d, JFC = 21 Hz), 122.6
0
0
(C3 ), 122.5 (C5 ), 80.0 (COH). 19F NMR (282 MHz,
CDCl3): d = 115.8. IR (KBr, cmꢀ1): m = 3396 (s), 1590
(s), 1504 (s), 1435 (m), 1225 (s), 1156 (m), 1039 (m), 831 (s).
4.3.5. Bis{N,O-[1,1-di(3-trifluoromethylphenyl)-1-(20-
pyridyl)methanolato]}oxovanadium(IV) (5)
Yield: 1.50 g (35%). Anal. Calc. for C40H24F12N2O3V
(859.55): C, 55.89; H, 2.81; F, 26.52; N, 3.26. Found: C,
55.5; H, 3.1; F, 26.0; N, 3.1%. CI-MS: m/z (%) = 857
(32, [M+]), 713 (25, [M+ꢀC6H4CF3]), 396 (100). IR
(KBr, cmꢀ1): m = 3031 (C–H, m), 1603 (C–N, m), 1474
(m), 1441 (m), 1329 (s), 1162 (s), 1070 (m), 1050 (m),
964 (V@O, s), 819 (m), 763(s), 698 (m). leff
(293 K) = 1.83 B.M.
4.3. General method for the preparation of the complexes 1–7
A solution of 10 mmol of ligand 1a–7a dissolved in 10
ml ethanol was added to a refluxing aqueous solution of
VO(SO4) Æ 5H2O (5 mmol) in 5 ml water. After refluxing
for 1 h, sodium acetate (15 mmol) dissolved in 10 ml water
was added to the mixture and refluxed for another 2 h. The
brown precipitate was collected, washed three times with
10 ml water, 10 ml ethanol, 10 ml diethyl ether, 10 ml
n-pentane and dried in vacuo for 8 h. (Scheme 1). The com-
pounds were purified by crystallization from CH2Cl2/n-
hexane.
4.3.6. Bis{N,O-[1,1-di(4-chlorophenyl)-1-(20-pyridyl)-
methanolato]}oxovanadium(IV) (6)
Yield: 2.83 g (78%). Anal. Calc. for C36H24Cl4N2O3V
(725.34): C, 59.61; H, 3.34; Cl, 19.55; N, 3.86; O, 6.62; V,
7.02. Found: C, 60.2; H, 3.5; Cl, 20.0; N, 3.8; O, 6.3; V,
7.0%. CI-MS: m/z (%) = 725 (27, [M+]), 614 (18,
[M+ꢀ(C6H4+Cl)]), 394 (100). IR (KBr, cmꢀ1): m = 3020
(m), 1603 (m), 1486 (s), 1471 (s), 1436 (m), 1396 (m),
1091 (s), 1040 (s), 1013 (s), 981 (V@O, s), 833 (s), 773
(m), 674 (m), 555 (w).
4.3.1. Bis{N,O-[1,1-diphenyl-1-(20-pyridyl)methanolato]}-
oxovanadium(IV) (1)
Yield: 2.13 g (73%). Anal. Calc. for C36H28N2O3V
(587.56): C, 73.59; H, 4.80; N, 4.77; O, 8.17. Found: C,
73.6; H, 4.9; N, 4.8; O, 7.7%. CI-MS: m/z (%) = 587 (21,
[M+]), 510 (13, [M+ꢀC6H5]), 326 (100). IR (KBr, cmꢀ1):
m = 3054 (C–H, m), 1603 (C@N, s), 1490 (C–C, s), 1470
(C–C, s), 1445 (C–C, s), 981.5 (V@O, s). leff (293 K) = 1.81
B.M.
4.3.7. Bis{N,O-[1,1-di(4-anisyl)-1-(20-pyridyl)-
methanolato]}oxovanadium(IV) (7)
Yield: 2.40 g (68%). Anal. Calc. for C40H36N2O7V
(707.66): C, 67.89; H, 5.13; N, 3.96; O, 15.83. Found: C,
67.8; H, 5.1; N, 4.0; O, 15.4%. CI-MS: m/z (%) = 707
(23, [M+]). IR (KBr, cmꢀ1): m = 977 (V@O, s). leff
(293 K) = 1.71 B.M.
4.3.2. Bis{N,O-[1,1-di(4-tert-butylphenyl)-1-(20-pyridyl)-
methanolato]}oxovanadium(IV) (2)
Yield: 3.19 g (77%). Anal. Calc. for C52H60N2O3-
V Æ H2O (830.00): C, 75.25; H, 7.53; N, 3.38; O, 7.71.
Found: C, 75.0; H, 7.3; N, 3.3; O, 8.2%. FAB-MS: m/z
(%) = 811 (16, [M+]), 678 (12, [M+ꢀ(C6H4+ C(CH3)3)]),
440 (100). IR (KBr, cmꢀ1): m = 3033 (C–H, arom, m),
2962 (C–H, aliph, s), 2903 (C–H, aliph, s), 1602 (C@N,
s), 1506 (C–C, arom, s), 1471 (C–C, arom, s), 1435 (C–
C, arom, s), 1362 (C(CH3)3, m), 958 (V@O, s). leff
(293 K) = 1.85 B.M.
4.4. Procedure for the epoxidation of 1-octene with oxygen
In a Schlenk tube equipped with a stirring bar 2 ml 1-
octene, 50 lml n-heptane as internal standard and
1 mol% catalyst were added. The flask was filled with
1 bar of oxygen. After thermostating at 100 ꢁC continu-
ously the oxygen conversion was monitored by a gasvo-
lume-apparatus. After 10 ml of oxygen was converted the

G.M. Lobmaier et al. / Journal of Organometallic Chemistry 691 (2006) 2291–2296
2295
reaction mixture was quenched to room temperature. The
solution was analyzed on a gas chromatograph.
tive reflections monitored every 200 reflections showed no
sign of significant decay [14a]. The data were corrected for
Lorentz and Polarisation effects. No absorption correction
was applied. A total number of 6393 reflections were col-
lected. Seven hundred and forty two negative intensities
together with 186 systematically absent reflections were
4.5. Procedure for the epoxidation of geraniole with tert-
butylhydrogenperoxide
In a Schlenk tube equipped with a stirring bar 6.8 ml
(50 mmol) geraniole, 50 lml diethyl ether as internal stan-
dard and catalyst 6 were added. After thermostating at
rejected from the original data set. After merging (Rint =
0.0190), a sum of 5284 independent reflections remained
and were used for all calculations [14b]. The structure
was solved by a combination of direct methods [14c]
and difference Fourier syntheses [14d]. All ‘‘heavy atoms’’
of the asymmetric unit were refined anisotropically. All
hydrogen atoms were calculated in ideal positions. Full-
matrix least-squares refinements were carried out by min-
imizing RwðF 2o ꢀ F c2Þ2 with SHELXL-93 weighting scheme.
Maximum shift/esd < 0.001 and maximum and minimum
peaks in the final difference Fourier Synthesis were 0.84
50 ꢁC
a tert-butylhydrogenperoxide/n-decane solution
(50 mmol) was added. Every 30 min a probe was analyzed
on a gas chromatograph.
4.6. Single crystal X-ray structure determination of complex
4 Æ 1/2CH2Cl2
X-ray-quality crystals of 4 Æ 1/2CH2Cl2 were obtained
directly from the preparation as described above. Preli-
minary examination and data collection was carried out
on a four-circle diffractometer (NONIUS CAD4) with
and ꢀ0.53 e Aꢀ3, respectively. Neutral atom scattering
˚
factors for all atoms and anomalous dispersion correc-
tions for the non-hydrogen atoms were taken from Inter-
national Tables for X-Ray Crystallography [14e].
Crystallographic data for 4 Æ 1/2CH2Cl2 are summarized
in Table 1.
˚
graphite monochromated Mo Ka radiation (0.71073 A).
A dark red single crystal of 4 Æ 1/2CH2Cl2 with dimensions
0.51 · 0.51 · 0.46 mm was sealed in a capillary. Cell con-
stants were obtained from least-squares refinements using
a setting angles of 25 carefully centered reflections in the
range 20.2ꢁ < h < 24.3ꢁ. The intensities of three representa-
Acknowledgements
The authors thank the Deutsche Forschungsgemeins-
chaft (DFG) and the Forschungsverbund Katalyse (FOR-
KAT) for financial support. We thank Prof. Dr. K.Ko¨hler,
Table 1
TU Munchen, for ESR measurements.
¨
Crystallographic data for {[(C12H8)(NC5H4)CO]2V@O} Æ 1/2CH2Cl2
(4 Æ 1/2CH2Cl2)
4 Æ 1/2CH2Cl2
Appendix A. Supplementary data
Formula
Fw
C73H50Cl2N4O6V2
1251.95
Crystallographic data (excluding structure factors) for
the structures reported in this paper have been deposited
with the Cambridge Crystallographic Data Centre as sup-
plementary publication No. CCDC-289230 (4 Æ 1/
2CH2Cl2). Copies of the data can be obtained free of
charge on application to CCDC, 12 Union Road, Cam-
bridge CB2 1EZ, UK, fax: +44 1223 336 033; e-mail:
deposit@ccdc.cam.ac.uk or at www.ccdc.cam.ac.uk/conts/
retrieving.html. Supplementary data associated with this
article can be found, in the online version, at
doi:10.1016/j.jorganchem.2005.11.034.
Color/habit
Crystal dimensions (mm3)
Crystal system
Space group
Dark red/octahedron
0.51 · 0.51 · 0.46
Monoclinic
I2/a (No. 15)
18.728(5)
19.507(2)
17.144(4)
102.79(1)
6108(2)
4
293
1.361
0.452
˚
a (A)
˚
b (A)
˚
c (A)
b (ꢁ)
3
˚
V (A )
Z
T (K)
Dcalc (g cmꢀ3
)
l (mmꢀ1
F(000)
)
2576
h Range (ꢁ)
1.53–26.02
h: ꢀ23 to 22/k: 0–24/l: 0–21
6393
5284/0.0190
4691
5284/0/393
0.0557/0.1520
0.0628/0.1563
1.038
References
Index ranges (h,k,l)
No. of reflections collected
No. of independent reflections/Rint
No. of observed reflections (I > 2r(I))
No. of data/restraints/parameters
R1/wR2 (I > 2r(I))a
[1] K.B. Sharpless, T. Katsuki, J. Am. Chem. Soc. 102 (1980) 5974.
[2] K. Nakajima, M. Kojima, J. Fujita, Chem. Lett. 9 (1986) 1483.
[3] R. Sheldon, second ed., in: B. Cornils, W.A. Herrmann (Eds.),
Applied Homogenous Catalysis with Organometallic Compounds,
vol. 1, Wiley-VCH, Weinheim, 2002, p. 412.
[4] C. Bolm, F. Bienewald, Angew. Chem. 107 (1996) 2883;
C. Bolm, F. Bienewald, Angew. Chem., Int. Ed.. 34 (1996) 2640.
[5] D. Schnurpfeil, K. Jaky, J. Prakt. Chem. 334 (1992) 165.
[6] S. Bellemin-Laponnaz, K.S. Coleman, J.A. Osborn, Polyhedron 18
(1999) 2533.
R1/wR2 (all data)a
GOF (on F2)a
ꢀ3
˚
Largest differential peak and hole (e A
)
+0.84/ꢀ0.53
2
2
1=2
a
R1 ¼ RðkF oj ꢀ jF ckÞ=RjF oj; wR2 ¼ fR½wðF 2o ꢀ F c2Þ ꢂ=R½wðF o2Þ ꢂg
;
2
1=2
GOF ¼ fR½wðF 2oF 2c Þ ꢂ=ðn ꢀ pÞg
.

2296
G.M. Lobmaier et al. / Journal of Organometallic Chemistry 691 (2006) 2291–2296
[7] G.M. Lobmaier, in: 6th International Symposium on the Activation
of Dioxygen and Homogeneous Catalytic Oxidation, Noordwikerh-
out, Netherland, 1996.
[8] (a) W.A. Herrmann, G.M. Lobmaier, T. Priermeier, M.R. Mattner,
B. Scharbert, J. Mol. Catal. 117 (1997) 455;
(b) MOLEN, Data Reduction Software for Nonius CAD4 devices, Delft,
The Netherlands, 1998;
(c) A. Altomare, G. Cascarano, C. Giacovazzo, A. Guagliardi, M.C.
Burla, G. Polidori, M. Camalli, J. Appl. Crystallogr. 27 (1994) 435–
436;
(b) B. Scharbert, G. Lobmaier, W.A. Herrmann (Hoechst AG),
German Patent DE 4447231 A1, 1996; DE 4447232 A1, 1996; DE
4447233 A1, 1996; DE 19536076 A1; European Patent EP 869843 A1,
1998; US 5969166 A, 1999; WO 9620788 A1, 1996.
[9] (a) F.J. McCarty, C.H. Tilford, M.G. Van Campen Jr., J. Am. Chem.
Soc. 79 (1957) 472;
(d) G.M. Sheldrick, SHELXL-93, Universita¨t Go¨ttingen, Go¨ttingen,
Germany, 1993;
(e) A.J.C. Wilson (Ed.), International Tables for Crystallography, vol.
C, Kluwer Academic Publishers, Dordrecht, The Netherlands, 1992,
Tables 6.1.1.4, 4.2.6.8, and 4.2.4.2;
(f) A.L. Spek,
A Multipurpose Crystallographic Tool, Utrecht
(b) H. Gilman, S.M. Spatz, J. Org. Synth. (1952) 1485.
[10] (a) B.E. Schultz, S.F. Gheller, M.C. Muetterties, M.J. Scott, R.H.
Holm, J. Am. Chem. Soc. 115 (1993) 2714;
University, Utrecht, The Netherlands, 2005.
[15] C.J. Carrano, C.M. Nunn, R. Quan, J.A. Bonadies, V.L. Pecoraro,
Inorg. Chem. 29 (1990) 944.
(b) A. Thapper, O. Balmes, C. Lorber, P.H. Svensson, R.H. Holm,
E. Nordlander, Inorg. Chim. Acta 321 (2001) 162.
[11] G. Wilkinson, R.D. Gillard, J.A. McCleverty (Eds.), first ed.,
Comprehensive Coordination Chemistry, vol. 3, Pergamon Press,
Oxford/New York, 1987.
[16] M. Shiro, Q. Fernando, Anal. Chem. 43 (1971) 1222.
[17] A.G. Orpen, L. Brammer, F.H. Allen, O. Kennard, D.G. Watson,
R. Taylor, J. Chem. Soc., Dalton Trans. (1989) S1.
[18] I. Kim, Y. Nishihara, R.F. Jordan, R.D. Rogers, A.L. Rheingold,
G.P.A. Yap, Organometallics 16 (1997) 3314.
[12] D. Attanasio, J. Phys. Chem. 90 (1986) 4952.
[19] D.F. Evans, J. Chem. Soc. (1959) 2003.
[13] D.R. Lide (Ed.), Handbook of Chemistry and Physics, 73rd ed., CRC
Press, Boca Raton, 1992.
[20] (a) G.M. Lobmaier, Ph.D. Thesis, Technische Universita¨t Munchen,
¨
1997, ISBN 3-933083-15-X.;
[14] (a) Data Collection Software for Nonius CAD4 devices, Delft, The
Netherlands, 1998.
(b) H. Trauthwein, Master Thesis, Technische Universita¨t Munchen,
¨
1995.