Preparation, X-ray structure, copolymerization with styrene of [(μ-H)Os3(μ-OCNMe2)(CO)9{P(CH 2CHCH2)Ph2}] and catalytic properties of the cluster/styrene copolymer

Article abstract of DOI:10.1016/j.jorganchem.2005.06.032

The complex [(μ-H)Os₃(μ-OCNMe₂)(CO) ₉{P(CH₂CHCH₂)Ph₂}] derived from the replacement of a lightly-stabilizing NMe₃ ligand in [(μ-H)Os ₃(μ-OCNMe₂)(CO)₉(NMe₃)] by allyldiphenylphosphine molecule was physico-chemically and X-ray structurally characterized and served further as a metal cluster monomer to be immobilized on a polymer surface. The copolymerization of this cluster monomer with styrene was studied. It was found that the cluster molecule, when copolymerized, maintains its integrity and the overall structure. The cluster copolymers obtained have been tested as catalysts for oxidative dehydrogenation and cyclohexenol hydroxylation reactions.

Full text of DOI:10.1016/j.jorganchem.2005.06.032

Journal of Organometallic Chemistry 690 (2005) 4258–4264
www.elsevier.com/locate/jorganchem
Preparation, X-ray structure, copolymerization with styrene
of [(l-H)Os (l-OCNMe )(CO) {P(CH CH@CH )Ph }]
and catalytic properties of the cluster/styrene copolymer
3
2
9
2
2
2
q
a
a
b
Svetlana I. Pomogailo , Gennady V. Shilov , Victoria A. Ershova ,
b
b
b
Alexander V. Virovets , Vladimir M. Pogrebnyak , Nina V. Podberezskaya ,
Anatoly V. Golovin , Gulzhian I. Dzhardimalieva , Anatolii D. Pomogailo
b
a
a,
*
a
Institute of Problems of Chemical Physics, Russian Academy of Sciences (RAS), Akad. Semenev ul., 1, Chernogolovka,
1
42432, Moscow Region, Russian Federation
Institute of Inorganic Chemistry, Russian Academy of Sciences (RAS), Siberian Branch, Akad. Lavrentev prosp. 3, Novosibirsk,
30090, Russian Federation
b
6
Received 31 January 2005; received in revised form 10 June 2005; accepted 10 June 2005
Available online 10 August 2005
Abstract
The complex [(l-H)Os
3
(l-OCNMe
2
)(CO)
9
{P(CH
2
CH@CH
2 2 3
)Ph }] derived from the replacement of a lightly-stabilizing NMe
ligand in [(l-H)Os (l-OCNMe )(CO) (NMe )] by allyldiphenylphosphine molecule was physico-chemically and X-ray structurally
3
2
9
3
characterized and served further as a metal cluster monomer to be immobilized on a polymer surface. The copolymerization of this
cluster monomer with styrene was studied. It was found that the cluster molecule, when copolymerized, maintains its integrity and
the overall structure. The cluster copolymers obtained have been tested as catalysts for oxidative dehydrogenation and cyclohexenol
hydroxylation reactions.
ꢀ
2005 Elsevier B.V. All rights reserved.
Keywords: Osmium cluster; Allyldiphenylphosphine; Crystal structure; Cluster–styrene copolymer; Radical polymerization; Catalytic oxidation
1
. Introduction
among other factors, on the ancillary ligand L with
which metal complex was modified. Phosphines are
known to be strong coordinating moieties which under-
go little to no dissociation from the metal in solution
and they are widely used ligands in metal-complex
homogeneous and heterogeneous catalysis due to their
governing role in providing activity and selectivity (see
for example [1]). In this regard, the complex modified
with L = allyldiphenylphosphine P(CH CH@CH )Ph
Since in much of its chemistry the triangulo-frame
and overall structure of hydridocarbonyl carboxamido
Os3 clusters [(l-H)Os (l-OCNR R )(CO) L] (R = H,
00
0
0
3
9
00
Alk; R = Alk, Ar; L = CO, amine, phosphine and
other 2-e ligand) remain intact, they may be conve-
niently anchored to a polymer surface and then studied
in a heterogeneous catalytic process without decomposi-
tion. The performance of catalysts is highly dependent,
2
2
2
considered to be perspective as metal-complex monomer
which may be immobilized to polymer by opening C@C
bond. On the other hand, recent publications show that
complexes containing 3-electron bridging carboxamido
q
6
4th Communications from ‘‘Synthesis and Reactivity of Metal-
Containing Monomers’’ series. For 63 communication see [V. Berezov-
skii et al., Russ. Chem. Bull. 54 (2005) (in press)].
00
0
*
ligands l-OCNR R are capable to producing an activa-
Corresponding author. Tel.: +7096 5227781; fax: +7096 5155420.
E-mail address: adpomog@icp.ac.ru (A.D. Pomogailo).
tion of N-allylic substrates resulted in their double-bond
0
022-328X/$ - see front matter ꢀ 2005 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2005.06.032

S.I. Pomogailo et al. / Journal of Organometallic Chemistry 690 (2005) 4258–4264
4259
ꢀ
1
[
1,2]-migration and simultaneous intra-substrate hydro-
Weak bands at 1630 and 1634 cm in IR (KBr pellet)
gen transfer [2]. While the catalytic properties of the
mentioned complexes, in particular in alkeneꢀs oxida-
tion, have not been yet examined, it is probably that
and Raman spectra (CHCl solution), respectively, are
3
assigned the uncoordinated C@C. While examples of
the allyl-to-1-propenyl type transformation are known
for compounds containing a tetracovalent phosphorus
atom, viz., in both coordinated to metal P(CH@CH-
CH )Ph [4] and allylphosphonium salts upon refluxing
mixed carboxamido:phosphine complex [(l-H)Os (l-
3
OCNMe )(CO) {P(CH CH@CH )Ph }] (1) may have
2
9
2
2
2
beneficial effects as anchored catalyst.
3
2
in benzene [5] or in the presence of alkoxides, [6]
the double bond shift and formation of 1-propenyl iso-
mer [(l-H)Os (l-OCNMe )(CO) {P(CH@CHCH )Ph }]
had not occurred with the cluster 1. H NMR spectrum
displays the characteristic set of three multiplets (ratio
1:2:2) corresponding to the three groups of protons from
the allylic fragment (CH multiplet at d = 5.57, four dou-
2
. Results and discussion
3
2
9
3
2
1
2
.1. Preparation and structure of [(l-H)Os (l-OCN-
3
Me )(CO) {P(CH CH@CH )Ph } (1)
2
9
2
2
2
The complex [(l-H)Os (l-OCNMe )(CO) {P(CH -
blets of doublets from c-CH around d = 5.06, and a-
CH H multiplet at d = 3.45). Comparison with the
spectrum of free allyldiphenylphosphine (d = 5.7, 4.9
3
2
9
2
2
00
0
CH@CH )Ph }] (1) was obtained as a major product
2
2
by treatment of a dichloromethane solution of the
labile NMe -substituted complex [(l-H)Os (l-OCN-
and 2.7 in CDCl ) [4] show small difference in the d
3
3
3
00
0
Me )(CO) (NMe )] (2) with allyldiphenylphosphine at
values for b- and c-protons, and the a-CH H multiplet
is shifted ꢁ0.7 ppm to lower field for the coordinated
ligand. The two methyl groups in the bridging carboxa-
mido ligand are non-equivalent due to hindered rotation
about an amide N–C bond and appear as two singlets at
d = 2.96 and 2.41.
The molecular structure of 1 is shown in Fig. 1 and
selected bond lengths and angles are listed in Table 1.
The crystallographic data, and details of the data collec-
tion and structure refinement procedures are summa-
rized in Table 2. The backbone of the molecule is an
2
9
3
ambient temperature under a dry argon atmosphere.
Small amounts of two side products, [(l-H)Os (l-OCN-
3
Me )(CO) (PHPh )] and [(l-H)Os (l-OCNMe )(CO) -
2
9
2
3
2
9
(
PPh )], have been also isolated as impurities from the
3
reaction [3]. The complex 1 is red, air-stable crystalline
solid. It has been characterized by spectroscopy and
X-ray crystallography (Fig. 1).
The spectroscopic data for the complex in solution
are fully consistent with the solid state structure. The
1
high-field metal-hydride region of H NMR spectrum
of 1 (in CDCl ) contains doublet from the bridging H
Os triangle with three metal–metal bonds.
3
3
at d = ꢀ13.50 with the value of l-hydrogen-phosphorus
The structure contains nine terminal carbonyl ligands.
coupling (J about 10 Hz) being indicative of the phos-
One of the Os–Os edges is doubly bridged by the hydride
HP
2
phine ligand bonded equatorially to the H-bound
and the carboxamido l,g -OCNMe ligands, the latter 3-
2
3
1
1
osmium through phosphorus. In P–{ H} NMR spec-
trum, a singlet from phosphorus atom is observed at
d = 14.58 relative to 85% H PO as external standard.
electron ligand being coordinated through both O and C
atoms. The doubly bridged Os(1)–Os(2) edge
˚
(2.9168(7) A) is longer than the other two Os–Os bonds
3
4
˚
(
Os(1)–Os(3) 2.8533(7) and Os(2)–Os(3) 2.8822(8) A).
The Os(1)–Os(3) distance is somewhat shorter relative
˚
to the another side edge (2.8533(7) vs. 2.8822(8) A) as well
˚
as to an Os–Os bond in Os (CO) (average 2.877 A [7]).
3
12
The Os(1) and Os(2) atoms of the edge spanned by bridg-
ing OCNMe ligand lie virtually in plane with its O and C
2
atoms. It is seen from Fig. 1 that the Os(1)Os(2)OC plane
is nearly perpendicular to the osmium triangle plane, sim-
ilar to that reported for other related doubly bridged com-
plexes [(l-H)Os (l-X)(CO) ] and their substituted
3
10
derivatives [8], with the value of dihedral angle between
the Os and the Os OC planes 101.7ꢁ. The position of
3
2
the bridging hydrogen atom is found experimentally. The
equatorial carbonyl ligand attached to the H-bound os-
mium is opened out away from the Os(1)–Os(2) and
Os(2)–Os(3) bonds as expected by the presence of the
hydride, Os(1)–Os(2)–C(21) 117.4(3)ꢁ and Os(3)–Os(2)–
C(21) 176.1(4)ꢁ in comparison with the corresponding an-
gles for C(33) 92.1(4)ꢁ/153.2(4)ꢁ and C(31) 104.3(4)ꢁ/
Fig. 1. Molecular structure of [(l-H)Os
P(CH CH@CH )Ph }] (1) showing the atom labelling scheme.
Thermal ellipsoids are drawn at 50% probability level.
3 2 9
(l-OCNMe )(CO) -
{
2
2
2
165.4(4)ꢁ in Os(CO) unit. The obtuse angle between the
4

4260
S.I. Pomogailo et al. / Journal of Organometallic Chemistry 690 (2005) 4258–4264
Table 1
Selected bond lengths (A) and angles (ꢁ) for [(l-H)Os
CO) {P(CH CH@CH )Ph }] (1)
Os and the Os(1)HOs(2) planes is 145.1ꢁ. The lengths of
3
˚
3
2
(l-OCNMe )-
the ordinary bond C(132)–C(133) 1.45(2) and the double
(
9
2
2
2
bond C(131)–C(132) 1.31(2) are as expected for an allylic
moiety.
Os(1)–Os(2)
Os(1)–Os(3)
Os(2)–Os(3)
Os(1)–P(1)
Os(1)–O(1)
Os(1)–C(11)
Os(2)–C(1)
Os(2)–C(21)
Os(2)–C(23)
Os(3)–C(34)
O(1)–C(1)
2.9168(7)
2.8533(7)
2.8822(8)
2.356(3)
2.121(7)
1.87(1)
2.10(1)
1.88(1)
1.85(1)
1.94(2)
1.29(1)
1.84(1)
1.45(2)
1.31(2)
2
.2. Copolymerization of the complex 1 and styrene
The specific character of structure of cluster mono-
mers comes from their chemical behavior in polymeriza-
tion reaction. As a rule, their homopolymerization
proceeds with difficulty, except that formation of some
oligomeric products was detected in a small yield [9].
Cluster monomers are best copolymerizing with tradi-
tional organic monomers [10,11]. The reactivity of clus-
ter monomers toward copolymerization depends on the
type of an unsaturated auxiliary ligand. For example,
copolymerizability of cluster complexes bearing 4-vinyl-
pyridine group is quite high. Copolymerization of
P(1)–C(131)
C(131)–C(132)
C(132)–C(133)
C(1)–O(1)–Os(1)
Os(2)–Os(1)–Os(3)
Os(1)–Os(2)–Os(3)
Os(1)–Os(3)–Os(2)
N(1)–C(1)–Os(2)
C(21)–Os(2)–Os(1)
C(23)–Os(2)–Os(1)
C(21)–Os(2)–Os(3)
C(23)–Os(2)–Os(3)
P(1)–Os(1)–Os(2)
P(1)–Os(1)–Os(3)
O(1)–Os(1)–Os(3)
O(1)–Os(1)–Os(2)
C(31)–Os(3)–Os(2)
C(31)–Os(3)–Os(1)
C(33)–Os(3)–Os(1)
C(33)–Os(3)–Os(2)
C(12)–Os(1)–Os(3)
C(12)–Os(1)–Os(2)
C(22)–Os(2)–Os(1)
C(22)–O(2)–Os(3)
C(11)–Os(1)–Os(2)
C(11)–O(1)–Os(3)
110.7(7)
59.92(2)
58.95(2)
61.13(2)
133.8(9)
117.4(3)
137.6(4)
176.1(4)
83.0(4)
4
-vinylpyridine complexes occurs even at their low con-
centrations (at 1–2 mol.%) in starting mixture of como-
nomers and results in the polymers modified abundantly
(up to 12 wt.%) with the cluster units. At the same time,
for many purposes, mainly for catalysis, copolymers
with a low content of cluster fragments are just benefi-
cial (the so-called low-percentage catalysts). In this re-
gard, cluster monomers containing an allylic ligand,
through which complex will be anchored to polymer,
possess an advantage over those containing the vinyl
group because allylic compounds are known to be less
favorable to be polymerized due to the chain transfer
degradation processes [12]. We have studied the copoly-
merization reaction of [(l-H)Os (l-OCNMe )(CO) -
108.29(8)
167.84(8)
88.7(2)
67.9(2)
104.3(4)
165.4(4)
92.1(4)
153.2(4)
90.4(4)
111.3(4)
104.3(4)
92.0(4)
143.7(3)
91.1(3)
3
2
9
{P(CH CH@CH )Ph }] (1) with styrene in the presence
2
2
2
of azobisisobutyronitrile (AIBN) as an initiator (Scheme
1
).
Cluster 1 has a poor solubility in styrene, and its con-
Table 2
centration in the reaction mixture is less than 1 mole%.
No appreciable period of induction has been observed
for the copolymerization reaction. The reaction rate in-
creases with concentration of the initiator (Fig. 2).
As expected, increase of AIBN concentration results
in decrease of the copolymer-molecular weights (Table
3) from the high concentration of the active radicals.
In organic solvent such as toluene, the same reaction
of 1 with styrene leads to a decrease of the yield of the
polymer, but percentage content of the cluster units in
the copolymer chain is not changed.
Crystallographic data for the complex 1
Compound
Formula
1
C
27 3
H22NO10Os P
F
w
1122.03
Monoclinic
P2 /c, No. 14
1
14.5620(10)
10.5840(10)
20.521(2)
96.530(8)
3142.3(5)
4
Crystal system
Space group
˚
a (A)
˚
b (A)
˚
c (A)
b (ꢁ)
˚
3
V (A )
Z
ꢀ
3
A slope of the straight line from a graphical depen-
D
x
(g cm
)
2.372
12.205
ꢀ
1
l (mm
)
dence of initial rate W of the 1/styrene copolymeriza-
0
Crystal size (mm), color
max (ꢁ)
Reflections total/unique
0.36 · 0.24 · 0.12, orange
50
4767/4572
0.0346
tion reaction on initiator concentration is near to 0.5
and so the rate of copolymerization is proportional to
the square root of the initiator concentration to indicate
a preferably bimolecular mechanism of the chain termi-
nation process.
2h
R
int
Final residuals
for 3217 Fhkl P 4r(F)
for all data
Goodness-of-fit for all data
R
1
0.0330
0.0663
0.787
wR
2
Distribution of the molecular weight values for
the 1/styrene copolymer points toward a non-metal

S.I. Pomogailo et al. / Journal of Organometallic Chemistry 690 (2005) 4258–4264
4261
CH=CH2
CH2
CH2=CH
) ~
~
(CH CH2 ) (CH CH2
n
m
Os
H
Os
H
AIBN
CH2
+
P
Ph
Ph
P
Ph
Ph
Os
Os
Os
Os
C
---- O
-
C
O
-
----
N
N
Me
Me
Me
Me
Scheme 1.
ꢀ
1
(
2045, 2002 for 1 and 2043, 2008 cm for the polymer).
The bands attributed to the stretching vibrations of
polystyrene units are also observed in the IR spectrum
ꢀ1
of the polymer (1601, 1493, 758, 689 cm ).
2.3. Oxidative dehydrogenation of 2,3,6-trimethyl-1,4-
hydroquinone in the presence of the 1/styrene copolymer
as catalyst
The reaction of oxidative dehydrogenation of 2,3,6-
trimethyl-1,4-hydroquinone (TMHQ) into 2,3,6-tri-
methyl-1,4-quinone (TMQ) under oxygen of the air
was chosen for two reasons as a model reaction in exam-
ining of catalytic properties of 1/styrene copolymer
(Scheme 3). The first reason is that no side products
have been observed in the literature in the reaction with
another catalysts in water-methanol media [13]. The sec-
ond reason is that TMQ plays a role of intermediate
compound in the synthesis of a-tocopherol (vitamin
E), and a-tocopherol can be prepared from TMQ by
its hydrogenation. As synthetic methods of TMQ pro-
ducing, a few catalytic reactions have been also de-
scribed. 2,3,6-Trimethylbenzene can be oxidized with
Fig. 2. Dependencies of the conversion degree of [(l-H)(l-OCN-
Me )Os (CO) (CH @CHCH PPh )] (1) on the reaction time at various
AIBN concentrations upon copolymerization of 1 with styrene: curve
2
3
9
2
2
2
1
, 0.07; 2, 0.39; 3 0.67; 4, 1.25; 5, 1.88; 6, 3.5 mole% of AIBN (70 ꢁC, in
bulk).
Table 3
Dependence of the average molecular weight of copolymer formed
a
from styrene and cluster monomer 1 on initiator concentration
2
+
2+
hydrogen peroxide in the presence of Cu and Co
b
Concentration of
AIBN (mol.%)
Content of Os in
copolymer (wt.%)
Mn
complexes with Shiff bases as ligands and gives TMQ
contaminated with diphenone, diphenoquinone and tar
by-products [14]. Being coated on aluminum oxide or
silica surfaces, it can be also oxidized with per-acids to
TMQ in yields of about 20%.
0
0
0
1
1
3
.07
.39
.67
.25
.88
.5
1.7
1.9
2.1
2.9
1.6
0.65
108400
65000
40000
37000
32000
17000
It was found that the 1/styrene copolymer is capable
of producing an activation the TMHQ oxidative dehy-
drogenation reaction under oxygen of the air. It was
shown also that this catalyzing polymeric material can
be used repeatedly without loss in its activity (Table 4)
with maintenance both of percentage Os-content and
the cluster structure. It follows from comparison of IR
data both for 1 and the polymeric catalyst registered be-
fore and after the reaction. Such a catalyst may be con-
sidered as heterogenised homogeneous catalyst [15]. The
advantage of such catalysts over conventional homoge-
neous catalysts is that they are influenced to a less extent
by catalytic poisons, and their catalytic activity remains
near the same through a number of experiments. The
catalysts are easily returnable from the reaction media
and can be further subjected to studying, if necessary,
or to reusing.
a
The concentration of the 1 monomer was 0.6 mol.%.
b
n
M is average molecular weight.
centered polymerization process, i.e., the osmium clus-
ter monomer 1 behaves mainly like an allylic mono-
mer, with its cluster substituent being intact, except
it makes the chain-transfer degradation occurrence
more probable and leads to a chain lengths shortening
(
Scheme 2).
As follows from comparison of the IR spectra of
1
/styrene copolymer and complex 1, the triangulo-frame
and overall structure of the copolymerized cluster mole-
cules are maintained. Near the same two main CO
stretching frequencies are observed in the both spectra

4262
S.I. Pomogailo et al. / Journal of Organometallic Chemistry 690 (2005) 4258–4264
~
CH2 CH CH2 CH2
+
CH2 CH
CH
CH2
PPh2
Os3
PPh2
Os3
~
CH2 CH
+
CH2 CH + CH =CH
2
CH2
PPh2
Os3
CH2
PPh2
Os3
~
CH2 CH CH CH
CH2
+
CH3 CH
CH2
PPh2
Os3
PPh2
Os3
Scheme 2.
HO
O
3. Conclusion
CH3
CH3
CH3
O2, catalyst
CH3
CH3
+
H2O
The cluster-containing monomer [(l-H)Os (l-OCN-
3
CH3
Me )(CO) {P(CH CH@CH )Ph }] is a molecular com-
2
9
2
2
2
HO
O
pound that include a framework of metal atoms,
which are separated by short distances permitting direct
metal–metal interaction. Such a framework is sur-
rounded by a polymerizable ligand.
TMHQ
TMQ
Scheme 3.
The copolymerization of cluster-containing mono-
mers is the most promising approach to obtaining a high
degree of uniformity and integrity of polynuclear forma-
tions in the polymers. This method is expected to be one
of the ways of preparing novel structurally organized
catalysts for different reactions.
Table 4
Catalytic oxidation of TMHQ into TMQ in the presence of 1/styrene
copolymer
a
Run
Initial reaction
rate (mole/L h)
Specific activity
(mole/(g-atom of Os) h)
1
2
3
4
0.32 ± 0.02
0.31 ± 0.02
0.30 ± 0.02
0.30 ± 0.02
0.29 ± 0.02
ꢀ5
188
182
177
177
177
4. Experimental
F5
a
The catalyst – 7.4 · 10 mole/L ([Os] = 1.71%), the substrate –
6 mmole/L, 10 mL water–methanol (1:1), 50 ꢁC.
4.1. General techniques
6
Syntheses were performed under an inert atmosphere
of argon. Solvents were purified by standard methods
prior to use [17]. tert-Butyl hydroperoxide (TBHP) was
used after removing water, acetone and methanol
admixtures by pumping-out. Infrared spectra were re-
corded in cyclohexane or from KBr pellet on a Specord
2.4. Oxidation of cyclohexene by hydrogen peroxide or
tert-butylhydroperoxide (TBHP) in the presence of the
1
/styrene copolymer catalyst
Studying of catalytic oxidation of cyclohexene (CH)
in the presence of the 1/styrene copolymer showed that
the process leads mainly to formation of unsaturated
alcohols with the major product (52–65% yields) being
cyclohexenol (CHol) (Table 5).
75-IR spectrometer using CaF
trum was registrated in CHCl solution on a Triplemate,
Spex (USA) spectrometer measured with excitation at
2
cell. The Raman spec-
3
1
31
1
633 nm. H and P{ H} NMR spectra were recorded
on a Bruker DPX-250 spectrometer using CDCl as sol-
vent and calibrated against internal TMS ( H) or exter-
Cyclohexenone (CHone) and cyclohexene oxide
3
1
(
OCH) are obtained in much smaller yields (0.8–2.5%).
3
1
Most likely, the catalytic oxidation of cyclohexene goes
through initial formation of cyclohexenehydroperoxide
nal 85% H PO ( P). Mass spectra were obtained on a
3 4
MX-1310 mass spectrometer at 50 eV. Preparative thin
layer chromatography (TLC) was carried out on com-
mercial Merck plates (Kieselgel 60 F254). The cluster
(
CHHP) and then proceeds as an autocatalytic process
[
16]. Traces of carboxyl-containing products as well as
small quantities of bicyclohexenyl and bi(2-cyclohex-
ene-4-hydroxy-1-yl) were also detected in the reaction
mixture. Kinetic measurements and their implication
in considerations regarding formation of these products
are to be published elsewhere.
[(l-H)Os
to the published procedure [18]. Allyldiphenylphosphine
was prepared from the allyl bromide and LiPPh accord-
ing to the literature procedure [19]. Me NO Æ 2H O were
prepared by the literature method [20].
3 2
(l-OCNMe )(CO)10] was prepared according
2
3
2

S.I. Pomogailo et al. / Journal of Organometallic Chemistry 690 (2005) 4258–4264
4263
Table 5
Hydroperoxide oxidation of cyclohexene with 1/styrene copolymer
4
Oxidizing agent
[Os] Æ 10 (mole/L)
Solvent
[CH] (mole/L)
T (ꢁC)
Yields of products (%)
OCH
CHone
CHol
H
2
O
2
5
CH
CH
benzene
toluene
2
Cl
Cl
2
2
2.0
2.1
4.1
4.1
30
30
50
50
0.8
0
2.5
1.8
47
48
25
25.7
52
52
62.5
TBHP
TBHP
TBHP
a
3.5
0.82
0.87
2
a
a
65.0
The other products: carboxyl-containing products, bicyclohexenyl and bi(2-cyclohexene-4-hydroxy-1-yl).
0
0
4
0
4
(
.2. Preparation of [(l-H)Os (l-OCNMe )(CO) -
J = 1.3 Hz, JHP = 11 Hz, ACH H ), 2.96 (s, 3H,
NMe), 2.41 (s, 3H, NMe), ꢀ13.50 (d, 1H, J
3
2
9
NMe )] (2)
=
HP
3
1
0.0 Hz, l-H).
A solution of [(l-H)Os (l-OCNMe )(CO) ] (41 mg,
3
2
10
3
0
.044 mmol) in diethyl ether (5 cm ) was treated with a
4.4. X-ray crystallography
3
methanolic solution (1 cm ) of Me NO Æ 2H O (9 mg,
3
2
0
.081 mmol) and then stirred at ambient temperature
Crystals of the complex 1 was grown from cyclohex-
for an additional time. The reaction was monitored by
TLC (hexane–CH Cl 2:1, v/v) and stopped as soon as
ane–CH Cl solution at room temperature.
2
2
Diffraction data were measured by the standard tech-
nique on Nonius CAD4 diffractometer at room temper-
ature using Mo Ka radiation. An empirical correction
for absorption was applied to the data using the 3 azi-
muthal scan curves. The structure was solved by direct
methods and refined with anisotropic thermal parame-
ters for all non-hydrogen atoms by full-matrix least-
squares using SHELX97 program package. The bridging
hydrogen atom was found on a final difference electron
density map and included into refinement with fixed
2
2
starting material (R 0.7) had disappeared (2 h), along
f
with a single band of product (R 0.5) being present on
f
TLC plate. The solution was then diluted with hexane
3
(
5 cm ) and filtered successively through two short silica
columns in order to remove residual Me NO. Removal
3
of the solvent under reduced pressure gave orange-red
crystalline powder of the cluster [(l-H)Os (l-OCNMe )-
3
2
(
CO) (NMe )] (2) (40 mg, 96%). IR (m(CO), C H ,
9 3 6 12
ꢀ
1
cm ): 2094m, 2048s, 2016s, 2005vs, 1974w, 1994s,
1
1
˚
966m, 1924m. H NMR (CDCl , d, ppm): 3.21 (s,
Uiso = 0.05 A [2]. The rest hydrogen atoms were refined
3
3
ꢀ
H, NMe), 2.97 (s, 9H, NMe ), 2.93 (s, 3H, NMe),
12.63 (s, 1H, l-H). This product was used in the fol-
geometrically. CCDC 252202 contains the supplemen-
tary crystallographic data for this paper. These data
can be obtained free of charge via www.ccdc.cam.
ac.uk/data_request/cif, or by emailing data_request
@ccdc.cam.ac.uk, or by contacting The Cambridge
Crystallographic Data Centre, 12, Union Road, Cam-
bridge CB2 1EZ, UK; fax: +44 1223 336033.
3
lowing steps without further purification.
4
(
.3. Preparation of [(l-H)Os (l-OCNMe )(CO) -
3 2 9
PPh CH CH@CH )] (1)
2
2
2
3
Cluster 1 (196 mg, 0.2 mmol) in CH Cl (5 cm ) and
2
2
3
allyldiphenylphosphine (0.05 cm , 0.23 mmol) were
mixed and stirred under dry argon atmosphere at r.t.
for 15 h, after which the mixture was subjected to pre-
parative TLC using hexane–diethyl ether (7:1, v/v) as
eluent. The major band (R 0.6) was extracted with
CH Cl and the extract was filtered. Removal of a
4.5. Copolymerization of [(l-H)Os (l-OCNMe )-
3
2
(CO) (PPh CH CH@CH )] (1) with styrene
9
2
2
2
Radical copolymerization of 1 with styrene was car-
ried out in bulk or in toluene in the presence of AIBN
(0.07–3.5 mol.%). The monomer [(l-H)Os (l-OCNMe )-
f
2
2
3
2
ꢀ
5
solvent under reduced pressure gave reddish-orange
crystalline solid which was then recrystallized repeatedly
(CO) (PPh CH CH@CH )] (0.02 g, 1.78 · 10 mole),
9
2
2
2
styrene (0.3 g, 0.003 mole), and AIBN were placed in
glass ampoule. The mixture was degassed by freeze–
thaw cycles to remove the oxygen from the reaction
mixture completely. The ampoule was then sealed in
vacuum and heated at 70 ꢁC for 3 h. The copolymer
formed was dissolved in 5 mL of benzene and precipi-
tated with 20 mL of ethanol, then dried at 30 ꢁC under
vacuum. The yield: 0.22–0.24 g (72–78%). Os, found
(
4–5 times) from hexane–CHCl3 (1:2 v/v) to give
red crystals of spectroscopically individual complex
[
(
(l-H)Os l-OCNMe )(CO) (PPh CH CH@CH )] (1)
1
3
2
9
2
2
2
ꢀ
136 mg, 61%). IR (m (CO), C H , cm ): 2088m,
6 12
2
044s, 2009vs, 1995m, 1984w, 1974w, 1942w; 1630w (m
1
(
C@C), KBr). H NMR (CDCl , d, ppm): 7.51 (m,
3
1
0H, Ph), 5.57 (m, 1H, @CHA), 5.12 (dd, 1H,
3
4
J = 10.3 Hz, J
= 3.6, J = 1.1 Hz, @CHH ), 5.00
(0.65–2.9 wt.%), M ¼ 17; 000–108; 400 Da, IR (KBr):
gem
cis
n
3
4
(
ddd, 1H,
J = 16.8 Hz, Jgem = 3.6,
CHHtrans), 3.45 (m, 2H, Jgem = 13.6, J = 7.2,
J = 1.3 Hz,
3468, 3026, 2922, 2043, 2008, 1602, 1494, 1438, 1371,
3
ꢀ1
@
1182, 1029, 907, 757, 698, 540 cm
.

4264
S.I. Pomogailo et al. / Journal of Organometallic Chemistry 690 (2005) 4258–4264
4.6. Oxidative dehydrogenation of 2,3,6-trimethyl-1,4-
hydroquinone
[2] (a) V.A. Ershova, S.V. Tkachev, A.V. Golovin, L.Ya. Alꢀt,
Mendeleev Commun. (1998) 208;
b) V.A. Ershova, A.V. Golovin, V.M. Pogrebnyak, J. Organo-
(
met. Chem. 658 (2002) 1–2,147.
The experiments were carried out in the thermostat-
ing three-neck flask provided with seal and condenser
at stirring in 10 mL water–methanol solution (1:1 vol.)
at 50 ± 0.2 ꢁC. Initial concentration of the substrate
[
3] V.A. Ershova, A.V. Golovin, L.A. Shekudyakova, P.P. Semyan-
nikov, S.I. Pomogailo, A.D. Pomogailo, Russ. Chem. Bull., Int.
Ed. (2000) 1448.
4] A. Jegorov, F. Ture cˇ ek, J. Organomet. Chem. 379 (1989) C5.
5] G. Bushi, H. Wuest, Helv. Chim. Acta 54 (1971) 1767.
6] T. Keough, M. Grayson, J. Org. Chem. 29 (1964) 631.
7] M.R. Churchill, B.G. BeBoer, Inorg. Chem. 16 (1977) 828.
[
[
[
[
2
,3,6-trimethyl-1,4-hydroquinone was 66 mmole/L. The
air was feeded with the rate of 6.2 L/h and the rate of
ꢀ
1
stirring was 2 s that provided the carrying out of the
process in the kinetic region. Before reaction the Os-
copolymer catalyst (0.08 g, the content of Os is 1.71%,
[8] (a) A.J. Deeming, Adv. Organomet. Chem. 26 (1986) 1;
(b) R.D. Adams, N.M. Golenbeski, J.P. Selegue, Inorg. Chem. 20
(
(
1981) 1242;
c) K.A. Azam, R. Dilshad, S.E. Kabir, M.A. Mottalib, M.B.
M
n
¼ 108; 000) was aged in water–methanol solution
Hursthouse, K.M.A. Malik, Polyhedron 19 (2000) 1081;
d) B.K.-M. Hui, W.T. Wong, J. Chem. Soc., Dalton Trans.
(
1:1 vol.) for 24 h. The initial rate for oxidizing dehydro-
(
genation was 0.3 mole/L h. The kinetic measurements
were carried out by control sampling followed by the
analysis of the content of TMHQ. The concentration
of substrate were analyzed by GLC.
(1998) 447;
(e) A.V. Virovets, V.A. Ershova, N.V. Podberezskaya, V.A.
Maksakov, Metalloorg. Khim. 4 (1991) 932 [Organomet. Chem.
USSR, 4 (1991) (Engl. Transl.)];
(
f) A. Vega, E. Spodine, A. Arce, J. Manzur, A.M. Garcia, M.T.
Garland, Acta Crystallogr., Sect. C 55 (1999) 322.
[
9] A.D. Pomogailo, V.S. Savostꢀyanov, Synthesis and Polymeriza-
tion of Metal-Containing Monomers, CRC Press, Boca Raton,
4
.7. Oxidation of cyclohexene by tert-butylhydroperoxide
1
994.
Hydroxylation of cyclohexene (CH) was carried out
[
10] N.M. Bravaya, A.D. Pomogailo, V.A. Maksakov, V.P. Kirin,
in an argon atmosphere in benzene at 30–50 ꢁC. The
concentrations of CH were 2.0–4.1 mole/L. Products
of the catalytic CH oxidation were analyzed by GLC
and on a YEOL YMS D 3000 chromato-mass
spectrometer.
V.P. Grachev, A.I. Kuzaev, Russ. Chem. Bull. 44 (1995) 1062.
[11] S.I. Pomogailo, G.I. Dzhardimalieva, V.A. Ershova, S.M. Aldo-
shin, A.D. Pomogailo, Macromol. Symp. 186 (2002) 155.
12] Kh.S. Bagdasarꢀyan, Theory of Radical Polymerization, Nauka,
Moscow, 1966.
13] V.G. Kharchuk, A.B. Shishmakov, O.V. Koryakova, V.V. Satar-
ova, L.A. Petrov, Zh. Org. Khim. 70 (2000) 993.
14] R.S. Drago, J. Goul, A. Zolombeck, D.K. Straub, J. Am. Chem.
Soc. 102 (1980) 1033.
15] A.D. Pomogailo, Catalysis by Polymer-Immobilized Metal Com-
plexes, Gordon & Breach, London, 1998.
16] S.N. Kholuiskaya, A.D. Pomogailo, N.M. Bravaya, S.I. Pomog-
ailo, V.A. Maksakov, Kinetics and Catalysis 44 (2003) 831.
[
[
[
[
[
Acknowledgments
This work was financially supported by the Russian
Foundation for Basic Research (Projects 03-03-06628
and 04-03-32634).
[17] A.J. Gordon, R.A. Ford, The Cemistꢀs Companion, Wiley, New
York, 1972.
[18] A. Mayr, Y.C. Lin, N.M. Boag, C.E. Campe, C.V. Knobler,
H.D. Kaesz, Inorg. Chem. 23 (1984) 4640.
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