Reactions of lanthanide acetylacetonates with triethylaluminum

Article abstract of DOI:10.1007/s10975-008-2019-9

The reactions of lanthanide acetylacetonates Ln(acac)₃· H₂O (Ln = Nd, Tb, Ho, Lu) with Et₃Al in toluene were studied by spectral methods (photoluminescence; taumetry; NMR, IR, and UV-vis spectroscopy) using GLC, volumetry,

Full text of DOI:10.1007/s10975-008-2019-9

ISSN 0023-1584, Kinetics and Catalysis, 2008, Vol. 49, No. 2, pp. 299–304. © MAIK “Nauka /Interperiodica” (Russia), 2008.
Original Russian Text © R.G. Bulgakov, S.P. Kuleshov, R.R. Vafin, A.G. Ibragimov, U.M. Dzhemilev, 2008, published in Kinetika i Kataliz, 2008, Vol. 49, No. 2, pp. 315–320.
Reactions of Lanthanide Acetylacetonates
with Triethylaluminum
R. G. Bulgakov, S. P. Kuleshov, R. R. Vafin, A. G. Ibragimov, and U. M. Dzhemilev
Institute of Petrochemistry and Catalysis, Russian Academy of Sciences, Ufa, 450075 Bashkortostan, Russia
e-mail: ink@anrb.ru
Received April 25, 2007; in final form, August 28, 2007
Abstract—The reactions of lanthanide acetylacetonates Ln(acac)3 · H2O (Ln = Nd, Tb, Ho, Lu) with Et3Al in
toluene were studied by spectral methods (photoluminescence; taumetry; NMR, IR, and UV–vis spectroscopy)
using GLC, volumetry, and chemical analysis.
DOI: 10.1134/S0023158408020195
INTRODUCTION
thesized according to [16]. The solvents (toluene and
benzene) were purified [17] by distillation from sodium
metal. Argon was passed through a Poglotitel Gazov
gas purifier.
Systems based on transition metal acetylacetonates
(TMAA) and organoaluminum compounds (OAC) are
widely used in the catalysis of chemical reactions of dif-
ferent types [1, 2]. The reaction products and the mech-
anisms of formation of catalytic complexes in these sys-
tems are well studied for Ti, Ni, Co, Fe, Cr, and Pd com-
pounds [3–8]. At the same time, data on reactions of
lanthanide acetylacetonates Ln(‡Ò‡Ò)3 · xH2O (LAA)
with OAC are lacking, although investigation of LAA–
OAC systems is essential both for gaining a deeper
insight into the Ziegler–Natta catalysts and for studying
the reactivity of lanthanide complexes.
In this work, we studied, for the first time, the reac-
tions of Ln(‡Ò‡Ò)3 · H2O (Ln = Nd, Tb, Ho, Lu) with tri-
ethylaluminum (TEA) using a wide range of physico-
chemical methods, including luminescence. The effi-
ciency of the latter in studying the synthesis and effects
of Ziegler–Natta lanthanide catalysts was shown in ear-
lier works [9–11]. Nd, Tb, Ho, and Lu lanthanides were
chosen from the lanthanide series for the following rea-
sons. The absorption spectra of the Nd and Ho com-
plexes contain bands due to supersensitive transitions,
whose parameters are highly sensitive to changes in the
coordination environment of the lanthanide [12]. The
Lu complex has the highest solubility in aromatic sol-
The reactions of LAA with TEA were carried out at
20°C under an argon atmosphere in a temperature-con-
trolled glass reactor fitted with a magnetic stirrer and
attached to a gas burette for measuring the volume of
the gas evolved. The reactor was charged with LAA
(0.04 mmol) and toluene (10 ml), the mixture was
stirred until the complete dissolution of LAA, and TEA
was added (TEA/LAA = 2–10). The reaction was per-
formed until the gas stopped evolving, and the resulting
solution was subjected to spectral analysis. IR and UV–
vis absorption spectra, 1H NMR and PL spectra, and the
Tb3+* ion lifetime (τ) were recorded using sealed quartz
cells or tubes under an Ar atmosphere.
Butadiene was dimerized with the LAA–TEA sys-
tem in a steel autoclave (V = 17 cm3). The autoclave
cooled to 5°C was sequentially loaded with LAA
(0.03 mmol), toluene (3 ml), butadiene (120 mmol),
and TEA (TEA/Ln = 6–12). The reaction was carried
out under continuous stirring at T = 80–120°C for 3 h.
Next, the reaction mixture was cooled down and
decomposed with a 10% HCl solution. The organic
phase was analyzed by GLC.
1
vents, and its H NMR spectra are very informative
[13]. The Tb complex is characterized by bright photo-
luminescence (PL) [12].
The coordinated water content of LAA was deter-
mined by the Fischer method [18]. Ethane and 4-vinyl-
cyclohexene (VCH) were analyzed on a Carlo Erba GC
6000 chromatograph (3 m × 4 mm column, poly(ethyl-
ene glycol) 6000, 15% on Chromatone for ethane;
3 m × 3 mm column, 15% Apiezon L on Chromaton
EXPERIMENTAL
Lanthanide acetylacetonates were synthesized and N-AW-DMCS for VCH). Absorption spectra in the IR
recrystallized according to a known procedure [14]. A and UV–vis regions were recorded on Specord 75IR
commercial gasoline solution of TEA (95%) was dis- and Specord M40 spectrophotometers. 1H NMR spec-
1
tilled in vacuo [15] (according to H NMR data, the tra were obtained on a JEOL FX-90Q spectrometer, and
alkoxyaluminum derivative content was <1%). Butadi- PL spectra were recorded on an Aminco Bowman spec-
ene (99.8%) was purified according to a standard pro- trofluorimeter. The τ(Tb3+*) value was measured using
cedure [9]. Tetraethylaluminoxane (Et2Al)2O was syn- a taumetric unit including an LGI-21 pulsed nitrogen
299

300
BULGAKOV et al.
D × 102
Vethane, % of theor.
D
80
60
40
20
2
1
6
1, 1'
1'
2, 2'
3, 3'
2', 3'
1
3
1' –3'
2, 3
1–3
0
0
6
3
0
0
60
120
180
240 t, s
2
Fig. 1. Kinetics of ethane evolution in the reaction
of çÓ(‡Ò‡Ò) · H O with Et Al in toluene at [Ho] = 4 ×
3
2
3
−3
10 mol/l, Al/Ln = 6, and T = 20°C.
4, 4'
laser (λexc = 337 nm; the measurement error and lower
measurement limit are 10% and 10 µs, respectively).
4'
1
0
4
4'
4
RESULTS AND DISCUSSION
Volumetric data. The addition of TEA to LAA
solutions in toluene (20°C) is accompanied by gas evo-
lution (Fig. 1). According to the results of analyses of
the liquid and gas phases, the gas was ethane. The for-
mation rate and amount of evolved EtH are independent
of the lanthanide nature. At Al/Ln = 2–10, the amount
of EtH corresponds to the stoichiometry of the equation
300
400
λ, nm
500
600
Fig. 2. Absorption spectra of solutions: (1, 1') Ln(‡Ò‡Ò) ·
H O complexes and (2, 2'–4, 4') Ln(‡Ò‡Ò) · H O–Et Al
system at Al/Ln = (2, 2') 2 and (3, 3') 6, (4, 4') after the
action of O on the reaction products in the Ln(‡Ò‡Ò)
3
2
3
2
3
·
3
2
H O–Et Al system at Al/Ln = 6. Ln = (1–4) Ho and (1' –4')
H2O + 2Et3Al
(Et2Al)2O + 2EtH.
2
3
–3
Nd ([Ln] = 4 × 10 mol/l, T = 20°C, toluene as solvent).
The evolution of EtH ceases in ~3–8 min, which is
much sooner than in the known heterogeneous reaction
of the LnCl3 · 6H2O crystalline hydrates with TEA
(>2 h) [9, 19].
(Et2Al)2é, which is the reaction product of water of
crystallization in LAA with TEA. Spectra for Al/Ln > 2
were not recorded.
IR spectra. The IR spectra of the LAA–TEA sys-
tem were studied for the Lu complex as an example,
which is the most soluble in benzene ([Lu] =
10−2 mol/l). The spectrum of Lu(‡Ò‡Ò)3 · H2O contains
the following absorption bands (cm–1): 1602 ν(ë=O);
1518 ν(C=C); 915, 1020 ν(C–C + C=O); 1382, 1187,
1068, 1014, 1260 ν(C–H + C–C); 789, 766, 749, 722,
646 ν(Ln–O); 422, 529, 551 (νring); 3250–3500 ν(OH).
They correlate well with the known spectra of LAA
[20, 21]. After TEA was added (Al/Ln = 2), the follow-
ing changes occurred in the spectra. Two less intense
bands appear at 1595 and 1589 cm–1 instead of the
absorption band at 1602 cm–1, and the absorption bands
at 1020 and 915 cm–1 undergo low-frequency shifts to
985 and 890 cm–1, respectively. The diffuse band due to
the stretching vibrations of the OH groups (3250–
3500 cm–1) disappears. In addition, new absorption
bands appear at 735 and 790–815 cm–1(Al–O–Al) and
UV–vis spectra. The spectra of the LAA complexes
in toluene (Fig. 2) have a diffuse maximum at 293
0.5 nm (ε = 40000 l mol–1 cm–1), whose position is
independent of the Ln nature and coincides with an ear-
lier reported spectrum [14]. This maximum is due to the
intraligand π
π* transition in the carbonyl group
[14, 23]. In the case of Ho and Nd, the spectrum con-
tains, in addition to the maximum at 293 nm, narrow
lanthanide f–f absorption maxima at 361 and 452 nm
(5I8
(4I9/2
3G6, I8
5G6) and at 522 and 575 nm
, I9/2
5
2,4
4
G
4G7/2), respectively. The
7/2, 5/2
maxima at 452 (Ho) and 575 (Nd) nm are due to super-
sensitive transitions [12]. The shorter wavelength f–f
maxima of Ho and Nd are disguised by the absorption
of toluene. The addition of TEA to solutions of LAA
(Al/Ln = 2) results in the shift of the maximum at
at 480, 545, and 654 cm–1 (Al–C). Based on published 293 nm to 300 nm (ε = 25500 l mol–1 cm–1) and in a
data [22], they can be assigned to aluminoxane decrease in its intensity. At Al/Ln = 2–6, the position of
KINETICS AND CATALYSIS Vol. 49 No. 2 2008

REACTIONS OF LANTHANIDE ACETYLACETONATES WITH TRIETHYLALUMINUM
301
τ(Tb3+*), µs
the maximum at 300 nm remains unchanged and its
intensity decreases (ε = 22 500 l mol–1 cm–1 forAl/Ln = 6).
No other changes occur in the spectrum at Al/Ln > 6. The
oscillator forces of the transitions responsible for the
supersensitive transition peaks decrease for both Ho
and Nd by ~25%, and the peak positions remain
unchanged (Fig. 2).
750
600
450
300
150
The absorption spectra change substantially (Fig. 2)
upon O2 bubbling through the solutions resulting from
the reaction of LAA with TEA (Al/Ln = 2). For
instance, the peak at 300 nm returns to its initial posi-
tion (293 nm), as in the spectrum of LAA before the
addition of TEA, and the peaks of the supersensitive
transitions at 452 (Ho) and 574 (Nd) nm are split into
peaks at 449 and 453 and at 570 and 576 nm, respec-
tively.
PL spectra and t(Tb3+*). The PL spectrum of a tol-
uene solution of Tb(‡Ò‡Ò)3 · H2O (not presented) con-
tains peaks at 491 (5D4–7F6), 545, 548 (5D4–7F5), and
584 (5D4–7F4) nm characteristic of Tb3+* [12]. The
τ(Tb3+*) value in toluene measured by us for
Tb(‡Ò‡Ò)3 · H2O (740 µs) and the same quantity
reported for Tb(‡Ò‡Ò)3 · 3H2O (730 µs) [24] coincide
within the measurement error. When TEA is added
(Al/Tb = 2), the PL intensity of the Tb(acac)3 · H2O
complex decreases without changes in peak positions in
the PL spectrum. The τ(Tb3+*) value decreases to
150 µs (Fig. 3). The subsequent addition of TEA results
in an insignificant (~7%) decrease in the PL intensity
and τ(Tb3+*) within the Al/Ln range from 2 to 6, and a
further increase in the metal ratio (Al/Ln > 6) does not
change the PL intensity and τ(Tb3+*).
0
2
4
6
8
10 Al/Tb
3+*
Fig. 3. Plot of τ(Tb ) versus the Et Al content for a tolu-
3
–3
ene solution of Tb(‡Ò‡Ò) · H O at [Tb] = 4 × 10 mol/l and
3
2
T = 20°C.
8 Hz), which are virtually the same as the signals of
TEA [26].
Butadiene dimerization. We studied the conver-
sion of butadiene under the action of LAA–TEA sys-
tems.As can be seen from the table, the LAA–TEA sys-
tems manifest some catalytic activity in butadiene
dimerization (butadiene conversion of ≤6%).
RESULTS AND DISCUSSION
The anhydrous LAA complexes and the complexes
containing one to three water molecules were described
earlier [23, 27]. According to our analysis (Fischer
method), the LAAs contain one H2O molecule. We
believe that, in the initial solutions, LAA ([Ln] = 4 ×
10–3 mol/l) exists as the dimer [Ln(‡Ò‡Ò)3 · H2O]2,
because such dimers are known to be formed in aro-
matic solvents even at lower LAA concentrations
([Ln] ≥ 10–3 mol/l) [13, 28–31]. The results of volumet-
ric analysis and IR spectroscopic data indicate that alu-
After é2 bubbling through the solution resulting
from the interaction in the Tb(‡Ò‡Ò)3 · H2O–TEA system
(Al/Ln = 2), the PL intensity and τ(Tb3+*) increase to
the levels characteristic of the initial Tb(‡Ò‡Ò)3 · H2O
complex.
1H NMR spectra. The reactions of LAA with TEA
were studied by NMR spectroscopy using the diamag-
netic complex Lu(‡Ò‡Ò)3 · H2O as an example. Note that
NMR data for LAA are lacking: there has been only a
single relevant publication [13], although lanthanide
β-diketonates are widely used in NMR spectroscopy as
shift reagents [25]. This is because of the low solubility
Dimerization and trimerization of butadiene in toluene by the
LAA–TEA and Ni(acac)2–TEA catalytic systems, respec-
tively
Butadiene
conversion, %
1
of LAA and the broadening of the H NMR signals
Ln T, °C
Product
even at room temperature [13]. The 1H NMR spectra of
the initial reactants in C7D8 contain the following sig-
nals, δ, ppm: Lu(‡Ò‡Ò)3 · H2O 1.80, 1.93 (s, 6H, CH3),
Tb
80
100
120
80
80
80
5
6
6
4
6
VCH
VCH
VCH
VCH
VCH
VCH
Tb
Tb
Nd
Pr
Ho
Ni*
3
5.30 (s, 3H, CH); TEA 0.28 (q, 2H, CH2, J = 8 Hz),
1.09 (t, 3H, CH3, 3J = 8 Hz). After the addition of TEA
(Al/Lu = 2), the broadened signal of the methinic pro-
ton of the acac ligand at 5.30 ppm shifts to 5.40 ppm
(without changing its half-width) and one signal at
1.80 ppm remains of the two methyl proton signals at
1.80 and 1.93 ppm. In addition, the spectrum exhibits
the following signals from aluminoxane, δ, ppm: 0.30
(q, 2H, CH2, 3J = 8 Hz) and 1.10 ppm (t, 3H, CH3, 3J =
6
35
100
Cyclododecatrienes
Note: Al/Ln = 3.
The yield of VCH and the total yield of cyclododecatrienes
are 100%.
* According to published data [40].
KINETICS AND CATALYSIS Vol. 49 No. 2 2008

302
BULGAKOV et al.
minoxane and ethane are the reaction products in the value as a result of the action of oxygen on the solutions
LAA–TEA system at any Al/Ln ratio. The UV-vis and resulting from the interaction in the Tb(‡Ò‡Ò)3 · H2O–
IR absorption and 1H NMR spectra show that
Et2Al(acac), which was previously identified in the
reactions of TMAA with TEA [3–8], does not form in
the LAA–TEA system. We observed no absorption
maxima or NMR signals characteristic of Et2Al(acac)
[3–8] (UV: λmax = 314 nm; IR: 1585, 1530, 1408, 1380,
1295, 1218, 1187, 485 cm–1; 1H NMR: acac 4.95 (s, 1H,
TEA system. Taking into account the aforesaid and the
known ability of OAC to react actively with the water
of crystallization of lanthanide salts [9, 11, 19], the
interaction between LAA and TEA can be described by
the empirical reaction
[Ln(acac)3 ⋅ H2O]2 + nEt3Al
[Ln(acac)3]2
1
CH) and 1.61 (s, 6H, CH3), Et 0.53 (q, 2H, CH2, J =
(I)
8.24 Hz) and 1.54 (t, 3H, CH3, 1J = 8.24 Hz)). The anal-
ysis of the PL spectra shows that the oxidation state of
the Ln3+ ion remains unchanged. Luminescence mea-
surements also suggest that the bonds of all three acac
ligands with the lanthanide are retained after the inter-
+ 2(Et2Al)2O + 4EtH + (n – 4)Et3Al.
Free water is known to react with TEA (Al/H2O = 2)
in toluene in two steps: the first step yields HOAlEt2,
which then reacts with the second TEA molecule to
action in the LAA–TEA system. This is indicated by give aluminoxane [32, 33]. This suggests that reaction
the restoration of the initial PL intensity and τ(Tb3+*
)
(I) proceeds according to the following scheme:
O
O
O
O
O
O
O
O
O
O
O
O
O
O
+Et3Al
–EtH
Ln
+Et3Al
–EtH
Ln
O
Ln
AlEt2
AlEt2
H
O
O
O
O
O
O
H
AlEt2
H
1/2
1/2
1/2
I
II
III
O
is an acac ligand
O
Scheme
Half of the LAA dimer is shown in simplified form 500 nm. Secondly, the dehydration of [Tb(‡Ò‡Ò)3 ·
as structure I in the scheme. The attack of the first TEA H2O]2 with the formation of anhydrous [Tb(‡Ò‡Ò)3]2
molecule on the coordination water of LAA results in cannot be responsible for the observed marked change
the formation of ethane and an intermediate hydroxyl- of τ(Tb3+*) from 740 to 150 µs, because the τ(Tb3+*) val-
containing adduct (structure II) in which the coordina- ues for Ln(‡Ò‡Ò)3 · 3H2O and Ln(‡Ò‡Ò)3 · H2O in tolu-
tion between the lanthanide and the oxygen atom is ene are nearly identical (730 and 740 µs). Therefore, it
retained (before the reaction of the oxygen atom is improbable that the removal of one more water mol-
belonging to the water molecule). The reaction of this ecule can be the cause of this dramatic (fivefold) short-
adduct with the second TEA molecule affords a com- ening of the lifetime of Tb3+* coordinated with several
plex (structure III) in which the oxygen atom of alumi- ligand (acac) molecules, which determine the lumines-
noxane is coordinated to the lanthanide. The complete cence properties of the Tb3+ ion. The sharp decrease in
removal of water molecules from the coordination the PL intensity and τ(Tb3+*) observed upon the addi-
sphere of the lanthanide is confirmed by the amount of tion of TEA to LAA (at Al/Ln = 2) can be due to the
EtH evolved in the reaction (2 mol per mole of LAA) dynamic quenching of Tb3+* by aluminoxane. How-
and by the disappearance of the IR absorption bands ever, if this were the case, these parameters would also
due to ç2é.
The alternative reaction mechanism involving the
formation of individual products (anhydrous dimer
decrease substantially at Al/Ln > 2. In fact, no decrease
of these parameters is observed experimentally (Fig. 3).
The formation of an LAA complex with aluminox-
[Ln(‡Ò‡Ò)3]2 and aluminoxane) seems improbable for ane seems to be quite likely in the light of the known
the following reasons. Firstly, the dehydration of LAA ability of lanthanides [34] and aluminoxane aluminum
upon interaction with TEA results in a shift of the acac [15] to coordinate with oxygen atoms of compounds of
ligand peak from 293 to 300 nm, whereas the absorp- various classes. In addition, the formation of similar
tion peak of the anhydrous Ho(‡Ò‡Ò)3 complex [27] complexes was discussed in a report devoted to diene
occurs at shorter wavelengths than the Ho(‡Ò‡Ò)3 · ç2é polymerization in the presence of the NdCl3 · 3TBP–
peak [23]. The maximum at 300 nm cannot be due to (iso-Bu2Al)2O system [35]. Two possible bridged struc-
aluminoxane, because the latter does not absorb at 280– tures of the complexes are suggested. The first has a
KINETICS AND CATALYSIS Vol. 49 No. 2 2008

REACTIONS OF LANTHANIDE ACETYLACETONATES WITH TRIETHYLALUMINUM
303
bond between the lanthanide and the aluminoxane oxy- gaseous products in the TMAA–TEA system are
gen atom. In the second structure, the lanthanide is mainly formed due to transformations of unstable inter-
bonded with the carbon atom of the isobutyl moiety.
mediates (alkyl and hydride derivatives of metals in the
oxidation states 2 and 1) and due to TEA decomposi-
tion by zero-valence metals or alkyl radicals [3–8, 37].
At this stage of investigation, the results obtained do
not allow us to describe unambiguously the structure of
the LAA complex with aluminoxane formed in the
Our results provide an explanation for the absence
LAA–TEA system. In addition to the compound with of catalytic activity in the LAA–R3Al systems (R = Et,
structure III, complexes of other types, including those iso-Bu) in diene polymerization [38]. We believe that
with Ln–C units, can be the final reaction product in the the retention of three acac ligands coordinated to the
LAA–TEA system. This conclusion is confirmed by the lanthanide is among the main causes of the catalytic
following arguments. The sharp decrease in the PL inertness of the LAA–R3Al system. This inference is
intensity and τ(Tb3+*) was observed earlier [9, 11] to confirmed by published data [39], according to which
result from the formation of Tb–C–Al units (where C is the catalysis of diene polymerization by the LnCl3 ·
the carbon atom of iso-Bu3Al) in the reaction of TbCl3 · 3TBP–R3Al system begins only after all ligand (TBP)
3TBP (where TBP is (C4H9O)3PO) with iso-Bu3Al. By molecules are removed from the coordination sphere of
contrast, the organic terbium complexes containing the lanthanide. The presence or absence of acac ligands
Tb–O bonds (acac as the ligand) are characterized by coordinated to the metal also governs the catalytic
rather high PL intensity and large τ(Tb3+*) values [11, activity of “metal complex–Et3Al” systems in butadi-
12, 36]. Furthermore, upon the action of oxygen on the ene dimerization and trimerization. We studied the
reaction products of the TbCl3 · 3TBP–iso-Bu3Al sys- dimerization of butadiene in the presence of the LAA–
tem, the PL intensity and τ(Tb3+*) increased, as in our TEA system. The results obtained were compared to
case. When oxygen interacts with the reaction products data available on butadiene trimerization with the
of the LAA–TEA system, aluminoxane is oxidized due Ni(acac)2–TEA system [40] (table). The butadiene con-
to oxygen insertion into the reactiveAl–Et bond to form version was found to be as low as ≤6% (table), whereas
(Eté)2AlOAl(éEt)2. In the case of a product having the butadiene conversion in the trimerization reaction
Ln–C units, this is accompanied by oxygen attacking reaches 100% [40]. This high yield is due to the fact
the even more reactive bond Ln–Et [25]. We believe that, in the Ni(acac)2–TEA system, as distinct from the
that the restoration of the PL intensity and τ(Tb3+*
)
LAA–TEA system, the acac ligands are abstracted
under the action of oxygen is caused just by the trans- from the metal and Ni(II) is reduced to Ni(0).
formation of the Ln–Et bond into an Ln–OEt bond. The
alternative interpretation of this effect in terms of Al–Et
bond oxidation yielding only (Eté)2AlOAl(éEt)2
ACKNOWLEDGMENTS
seems improbable because this compound exerts no
effect on the PL intensity or τ(Tb3+*). This was estab-
lished experimentally by adding, to LAA, the alkoxide
(Eté)2AlOAl(éEt)2 synthesized by an independent
method [15].
This work was supported by the Federal Agency on
Science and Innovation (state contract no. 02.434.11.2026
of August 1, 2005).
REFERENCES
The results of our study indicate several significant
distinctions between the reactions of TEA with LAA
and TMAA. Firstly, no lanthanide is reduced by TEA in
the LAA–TEA system. If this reduction had taken
place, it would have easily been detected owing to the
substantial absorption and PL spectral differences
between the trivalent and divalent lanthanides [12]. By
contrast, in the reactions of TMAA with TEA the met-
als are reduced to the zero-valence state. Secondly,
upon the action of TEA on LAA, the acac ligands
remain in the coordination sphere of the lanthanide,
whereas TMAA loses one or even all acac ligands to
form Et2Al(acac) or Al(acac)3 [3–8]. Thirdly, EtH is the
only gaseous product of the reactions of LAA with
TEA, and the amount of EtH (2 mol) is independent of
the Al/Ln ratio. In the case of TMAA, a wide variety of
gaseous products is formed (hydrogen, ethylene,
ethane, cis- and trans-but-2-enes, but-1-ene, and
butane), whose yields depend on the Al/Ln ratio and
varies between 1.54 and 5.15 mol. In the LAA–TEA
system, EtH results from the reaction of the water of
crystallization of LAA with TEA. On the contrary, the
1. Dzhemilev, U.M., Popod’ko, N.R., and Kozlova, E.V.,
Metallokompleksnyi kataliz v organicheskom sinteze
(Metal Complex Catalysis in Organic Synthesis), Mos-
cow: Khimiya, 1999.
2. Kolkhaun, Kh.M., Kholton, D., Tompson, D., and
Tvigg, M., Novye puti organicheskogo sinteza: Prak-
ticheskoe primenenie perekhodnykh metallov (New
Ways in Organic Synthesis: Application of Transition
Metals), Moscow: Khimiya, 1989.
3. Belykh, L.B., Goremyka, T.V., Rokhin,A.V., Titova,Yu.Yu.,
Umanets, V.A., and Shmidt, F.K., Koord. Khim., 2005,
vol. 31, no. 10, p. 757 [Russ. J. Coord. Chem. (Engl.
Transl.), vol. 31, no. 10, p. 719].
4. Nindakova, L.O., Shmidt, F.K., Saraev, V.V., Shai-
nyan, B.A., Chipanina, N.N., Umanets, V.A.,
Belonogova, L.N., and Toryashinova, D.-S.D., Kinet.
Katal., 2006, vol. 47, no. 1, p. 59 [Kinet. Catal. (Engl.
Transl.), vol. 47, no. 1, p. 54].
5. Chirkov, N.M., Matkovskii, P.E., and D’yachkovskii, F.S.,
Polimerizatsiya na kompleksnykh metalloorganicheskikh
katalizatorakh (Polymerization on Organometallic Com-
plex Catalysts), Moscow: Khimiya, 1976.
KINETICS AND CATALYSIS Vol. 49 No. 2 2008

304
BULGAKOV et al.
6. Dmitrieva, T.V., Ratovskii, G.V., Kamchatova, T.B., and 22. Boleslawski, M. and Serwatowski, J., J. Organomet.
Shmidt, F.K., Koord. Khim., 1982, vol. 8, no. 11,
Chem., 1983, vol. 254, p. 159.
p. 1457.
23. Zakurin, N.V., Reshetova, M.D., Vasil’kov, A.Yu., and
Kogan, A.S., Dokl. Akad. Nauk SSSR, 1982, vol. 267,
no. 2, p. 394.
7. Dmitrieva, T.V., Ratovskii, G.V., Donskikh, V.I., and
Shmidt, F.K., Koord. Khim., 1981, vol. 7, no. 7, p. 1029.
24. Voloshin, A.I., Shavaleev, N.M., and Kazakov, V.P.,
J. Photochem. Photobiol., A, 2000, vol. 134, nos. 1–2,
p. 111.
8. Dmitrieva, T.V., Ratovskii, G.V., and Shmidt, F.K.,
Koord. Khim., 1984, vol. 10, no. 2, p. 213.
9. Bulgakov, R.G., Kuleshov, S.P., Zuzlov, A.N., Mulla-
galiev, I.R., Khalilov, L.M., and Dzhemilev, U.M.,
J. Organomet. Chem., 2001, vol. 636, p. 56.
25. Bochkarev, M.N., Kalinina, G.S., Zakharov, L.N., and
Khorshev, S.Ya., Organicheskie proizvodnye redkoze-
mel’nykh elementov (Organic Derivatives of Rare-Earth
Elements), Moscow: Nauka, 1989.
10. Kuleshov, S.P., Bulgakov, R.G., Sharipov, G.L., Bik-
baeva, G.G., Safonova, L.A., Gavrilova, A.A., and
Sharapova, L.I., Izv. Akad. Nauk, Ser. Khim., 1996, no. 8,
p. 1907.
26. Boleslawski, M., Pasynkiewicz, S., Kunicki, A., and Ser-
watowski, J., J. Organomet. Chem., 1983, vol. 116,
p. 285.
11. Bulgakov, R.G., Kuleshov, S.P., Zuzlov, A.N., Vafin, R.R.,
Rusakov, S.V., Mullagaliev, I.R., Dzhemilev, U.M., and
Monakov, Yu.B., Kinet. Katal., 2003, vol. 44, no. 5,
p. 783 [Kinet. Catal. (Engl. Transl.), vol. 44, no. 5,
p. 718].
27. Przystal, J.K., Bos, W.G., and Liss, I.B., J. Inorg. Nucl.
Chem., 1971, vol. 33, p. 679.
28. Duncan, N.J. and Shepperd, M.T., J. Chem. Soc., Fara-
day Trans., 1976, vol. 72, no. 2, p. 557.
12. Poluektov, N.S., Koronenko, L.I., Efryushina, N.P., and
Bel’tyukova, S.V., Spektrofotometricheskie i lyuminests-
entnye metody opredeleniya lantanidov (Spectrometrc
and Luminescent Methods of Lanthanide Determina-
tion), Kiev: Naukova Dumka, 1989.
29. Tanaka, F. and Ishibashi, T., J. Chem. Soc., Faraday
Trans., 1996, vol. 92, no. 2, p. 1105.
30. Villiers, J.P.R.D. and Boeyens, J.C.A., Acta Crystallogr.,
Sect. B: Struct. Sci., 1971, vol. 27, no. 12, p. 692.
31. Villiers, J.P.R.D. and Boeyens, J.C.A., Acta Crystallogr.,
Sect. B: Struct. Sci., 1971, vol. 27, no. 12, p. 2335.
13. Kemlo, J.A., Duncan, N.J., and Shepperd, M.T., Inorg.
Chem., 1977, vol. 16, no. 5, p. 1111.
32. Storr, A., Jones, K., and Laubengayer, A.W., J. Am.
Chem. Soc., 1968, vol. 90, no. 12, p. 3173.
14. Sager, W.F., Filipescu, N., and Serafin, F.A., J. Phys.
Chem., 1965, vol. 69, no. 4, p. 1093.
33. Boleslawski, M. and Serwatowski, J., J. Organomet.
Chem., 1983, vol. 255, no. 3, p. 285.
15. Korneev, N.N., Khimiya i tekhnologiya alyuminiiorgan-
icheskikh soedinenii (Organoaluminum Compound
Chemistry and Technology), Moscow: Khimiya, 1979.
34. Yatsimirskii, K.B., Kostromina, N.A., Sheka, Z.A.,
et al., Khimiya kompleksnykh soedinenii redkoze-
mel’nykh elementov (Chemistry of Rare-Earth Complex
Compounds), Kiev: Naukova Dumka, 1966.
16. Razuvaev, G.A., Sangalov, Yu.A., Nel’kenbaum, Yu.Ya.,
and Minsker, K.S., Izv. Akad. Nauk SSSR, Ser. Khim.,
1977, no. 12, p. 2547.
35. Mullagaliev, I.R., Doctoral (Chem.) Dissertation, Ufa:
17. Weissberger, A., Proskauer, E.S., Riddick, J.A., and
Toops, E.E., Technics of Organic Chemistry, vol. 7:
Organic Solvents: Physical Properties and Methods of
Purification, New York: Wiley, 1955.
Inst. of Organic Chemistry, 2007.
36. Bulgakov, R.G., Kuleshov, S.P., Karamzina, D.S., Makh-
mutov, A.R., Vafin, R.R., Shestopal, Ya.L., Mullagaliev,
I.R., Monakov, Yu.B., and Dzhemilev, U.M., Kinet.
Katal., 2006, vol. 47, no. 5, p. 760 [Kinet. Catal. (Engl.
Transl.), vol. 47, no. 5, p. 737].
18. Charlot, G., Les methodes de la chimie analytique, Paris:
Masson, 1961.
19. Bulgakov, R.G., Kuleshov, S.P., Makhmutov, A.R.,
Vafin, R.R., Karamzina, D.S., Golikova, M.T., Shesto-
pal, Ya.L., Usmanov, S.M., and Dzhemilev, U.M., Kinet.
Katal., 2006, vol. 47, no. 4, p. 589 [Kinet. Catal. (Engl.
Transl.), vol. 47, no. 4, p. 572].
37. Dzhemilev, U.M., Kukovinets, A.G., and Tolstikov, G.A.,
Izv. Akad. Nauk SSSR, Ser. Khim., 1978, no. 6, p. 1379.
38. Monakov, Yu.B. and Tolstikov, G.A., Kataliticheskaya
polimerizatsiya 1,3-dienov (Catalytic Polymerization of
1,3-Dienes), Moscow: Nauka, 1990.
20. Byrke, A.I., Magdesieva, N.N., Martynenko, L.I., and
Spitsyn, V.I., Zh. Neorg. Khim., 1967, vol. 12, no. 3,
p. 666.
39. Monakov,Yu.B., Sabirov, Z.M., Urazbaev, V.N., and Efi-
mov, V.P., Kinet. Katal., 2001, vol. 42, no. 3, p. 346
[Kinet. Catal. (Engl. Transl.), vol. 42, no. 3, p. 310].
21. Razvina, T.I., Khomenko, V.S., Kuznetsova, V.V., and
Puko, R.A., Zh. Prikl. Spectrosk., 1973, vol. 19, no. 5, 40. Kukovinets, A.G., Cand. Sci. (Chem.) Dissertation, Ufa:
p. 866.
Inst. of Organic Chemistry, 1981.
KINETICS AND CATALYSIS Vol. 49 No. 2 2008