New aluminum 2,2′-methylenebis(4-chloro-3-methyl-6-(isopropyl) phenoxides): Structural characterization of an unusual ionic aluminum bisphenoxide [Al(THF)4(Cl)2]+[Al(mcmip) 2]-·x THF

Article abstract of DOI:10.1016/j.inoche.2013.01.021

The synthesis and X-ray structure determination of an uncommon ionic aluminum bisphenoxide [Al(THF)₄(Cl)₂] ⁺[Al(mcmip)₂]^-·1.1 THF (1) and its neutral analogue (mcmip)Al(CH₂CH₃)(THF) (2) are reported (mcmipH₂: 2,2′-methylenebis(4-chloro-3-methyl-6-(isopropyl) phenol). The ligand was reacted in THF with diethyl aluminum chloride, respectively triethyl aluminum, under liberation of ethane to yield crystalline aluminum bisphenoxides. Compound 2 exhibits the usual structural features found in neutral THF-aluminum bisphenoxides adducts whereas the ionic compound 1 consists of a cationic octahedral aluminum dichloride moiety, [Al(THF) ₄(Cl)₂], and an anionic di-bisphenoxide aluminate fragment [Al(mcmip)₂] containing two 2,2′-methylenebis(4-chloro-3- methyl-6-(isopropyl)phenol) ligands. Both aluminum bisphenoxides were tested as catalysts in the copolymerization of cyclohexene oxide with CO₂ and displayed similar good catalytic activities although the carbonate amounts present in the copolymer remain low.

Full text of DOI:10.1016/j.inoche.2013.01.021

Inorganic Chemistry Communications 30 (2013) 69–73
Contents lists available at SciVerse ScienceDirect
Inorganic Chemistry Communications
journal homepage: www.elsevier.com/locate/inoche
New aluminum 2,2′-methylenebis(4-chloro-3-methyl-6-(isopropyl)phenoxides):
Structural characterization of an unusual ionic aluminum bisphenoxide
+
−
[
Al(THF) (Cl) ] [Al(mcmip) ] ·x THF
4
2
2
1
Jakub K. Sypień , Thomas A. Zevaco ⁎, Annette Flicker, Olaf Walter, Eckhard Dinjus
Karlsruhe Institute of Technology, Institute of Catalytic Research and Technology, Postfach 3640, 76021 Karlsruhe, Germany
a r t i c l e i n f o
a b s t r a c t
Article history:
The synthesis and X-ray structure determination of an uncommon ionic aluminum bisphenoxide
Received 17 September 2012
Accepted 23 January 2013
Available online 1 February 2013
+
−
[
Al(THF)
4
(Cl)
2
]
[Al(mcmip)
2 2 3
] ·1.1 THF (1) and its neutral analogue (mcmip)Al(CH CH )(THF) (2) are
2
reported (mcmipH : 2,2′-methylenebis(4-chloro-3-methyl-6-(isopropyl)phenol). The ligand was reacted in THF
with diethyl aluminum chloride, respectively triethyl aluminum, under liberation of ethane to yield crystalline
aluminum bisphenoxides. Compound 2 exhibits the usual structural features found in neutral THF-aluminum
bisphenoxides adducts whereas the ionic compound 1 consists of a cationic octahedral aluminum dichloride
Keywords:
Aluminum
X-ray structure determination
moiety, [Al(THF)
2,2′-methylenebis(4-chloro-3-methyl-6-(isopropyl)phenol) ligands. Both aluminum bisphenoxides were tested
as catalysts in the copolymerization of cyclohexene oxide with CO and displayed similar good catalytic activities
although the carbonate amounts present in the copolymer remain low.
4 2 2
(Cl) ], and an anionic di-bisphenoxide aluminate fragment [Al(mcmip) ] containing two
2,2′-Methylene-bisphenoxide
Aliphatic polycarbonate
2
©
2013 Elsevier B.V. All rights reserved.
Soluble aluminum compounds like organoaluminum compounds
1] or pure aluminum alkoxides [2] play an important role as homoge-
[6]. Within this context, it was interesting to synthesize a “tailored”
aluminum 2,2′-methylene-bisphenoxide having: i) a sterically
demanding group at locations 6,6′ to shield at some extend the
active coordination site of the catalyst and so repress the formation
of higher oligomeric aluminum bisphenoxides, ii) an alkyl substitu-
ent at locations 3,3′ of the phenol rings in order to “twist” the bisphenol
ligand via the mutual steric hindrance of these substituents and modify
in that way the size of the coordination site, and iii) an electron
withdrawing group (−I effect considered) at locations 4,4′ to ensure
a high Lewis acidity and compete with the steric/electronic influence
of the substituents at locations 6 and 3. The synthesis of such a
bisphenol was described as early as in the 50s and was the subject of
several patents [7], the molecule showing an interesting potential
as pulmonary antiseptic (biclotymol [CAS 15686-33-6]). The struc-
tural characterization of this particular bisphenol was performed
by Rantsordas et al. [8] and the use as a chelating ligand in alumi-
num catalysts was firstly reported by C.-C. Lin and co-workers in
2001 [9]. Interestingly this ligand was newly reported in a patent
dealing with zirconium-based catalysts used in the oligomerization
of ethylene [10].
[
neous catalysts in organic synthesis. Molecular aluminum derivatives
are well known to display variable molecular compositions ranging
from monomeric to polymeric aggregates owing to the aluminum's
ability to easily adopt tetrahedral, octahedral as well as the less abun-
dant trigonal–bipyramidal coordination geometries [3]. For this reason
collecting spectroscopic information on the active aluminum species
involved in a catalytic process can be achieved most of the time only
via a “simplification” of the investigated catalytic system. Considering
more specifically the aluminum alkoxides used as Lewis acid catalysts
[
2], the utilization of an ancillary chelating alkoxo ligand can elegantly
provide a structurally well-defined, “single-site” catalyst. Bulky 2,2′-
methylene-bisphenols constitute versatile and easy-to-handle
toolbox” for the coordination chemist as reported by many research
a
“
groups [4]. The synthesis on a large scale of these chelating ligands
from formaldehyde and the corresponding substituted phenols is
relatively easy, allowing the rapid development of a ligand library [5].
During the course of our studies on new potential catalysts of the
2
copolymerization of CO and epoxides, we became interested in systems
involving aluminum bisphenoxides and synthesized as well as
structurally characterized different new aluminum compounds
The title ligand, 2,2′-methylenebis(4-chloro-3-methyl-6-(isopropyl)
phenol), was synthesized from the reaction of paraformaldehyde with
4-chloro-3-methyl-6-(isopropyl)phenol in heptane in the presence
of catalytic amounts of sulphuric acid following the general synthetic
method reported in the literature [7,9] (Scheme 1).
A solution of diethyl aluminum chloride in THF was added dropwise
to a cold suspension of the substituted phenol. The suspension was
allowed to warm up to room temperature to become a colorless
⁎
Corresponding author at: Karlsruhe Institute of Technology (KIT), Institute of Catalytic
Research and Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-
Leopoldshafen, Germany. Fax: +49 7247 82 2244.
E-mail address: thomas.zevaco@kit.edu (T.A. Zevaco).
Dedicated to the memory of Dr. Jakub Konrad Sypień.
1
1387-7003/$ – see front matter © 2013 Elsevier B.V. All rights reserved.
http://dx.doi.org/10.1016/j.inoche.2013.01.021

70
J.K. Sypień et al. / Inorganic Chemistry Communications 30 (2013) 69–73
OH
Cl
OH
HO
H2
C
C H
7
16
2
+
H C=O
2
+
H O
2
Cat. H SO4
2
Cl
Cl
2
Scheme 1. Synthesis and structure of 2,2′-methylenebis(4-chloro-3-methyl-6-(isopropyl)phenol) (mcmipH ).
solution whereas an evolution of ethane was observed. After a couple of
hours THF was evaporated to yield a pale waxy compound which solid-
ified after a couple of hours. The aluminum bisphenoxide 1 was dissolved
again in THF and left a couple of weeks at −25 °C; a small amount of
colorless single crystals suitable for an X-ray structural determination
small range indicating that the negative charge is delocalized over the
aluminate anion (Al1–O1:1.726(4) Å; Al1–O2: 1.739(4) Å; Al1–O4:
1.746(4) Å; Al1–O3 1.747(4) Å). The angles and interatomic distances
found within the bisphenoxide ligands are comparable to those found
in the complexes reported by Lin [9]. The interatomic distances measured
within the two distinct bisphenoxide ligands of the anion are quite simi-
lar whereas the overall geometries of the two ligand/aluminum sub-units
are subtly different. This can be clearly seen considering the two eight-
membered rings formed by the ligand backbones and the aluminum cen-
ter [14] which display via the steric hindrance of the methyl substituents
a distorted boat–boat conformation. The angles involving the two eight-
membered rings (O1–Al1–O2 108.3 and O3–Al1–O4 105.7°) are clearly
distinct, being nevertheless within the range usually found for mono-
meric tetrahedrally coordinated aluminum bisphenoxides [4,9,14].
The unusual dinuclear structure found in our case markedly differs
from similar Al(mcmip) bisphenoxides isolated and structurally charac-
terized by Lin and co-workers after reaction of the same ligand
with trimethyl aluminum. In that particular case the compound
displayed standard neutral donor–acceptor features of the type
[11] could be eventually isolated, these crystals are stable at low tem-
peratures, slowly deteriorating above 0 °C. Surprisingly, we observed
that, instead of displaying an usual neutral adduct structure of type
(
bisphenoxide-O,O′)Al(Cl)(THF), the isolated aluminum bisphenoxide
+
presented an uncommon dinuclear ionic structure [Al(THF)
4
(Cl)
2
]
−
[Al(mcmip)
2
] ·1.1 THF. Crystals of the compound 1 are monoclinic,
crystallizing in the space group P2(1)/n (no. 14) [12].
The ORTEP diagram of the ionic aluminum bisphenoxide is illustrated
in Fig. 1. Selected bonds and angles are listed in the Supplementary ma-
−
2
terial. The molecular structure of 1 consists of discrete [(mcmip) Al]
aluminate anions containing two bisphenoxides bound in an al-
most symmetrical way to the aluminum center and of symmetrical
+
[
AlCl
2
(THF)
4
]
cations with apical chlorine atoms with no short
interionic contacts. The complex co-crystallized with 1.1 molecules
of THF per unit: 0.5 plus 0.6 being disordered. Considering the
cation, the aluminum atom is situated at the center of an almost perfect
octahedron, with Al–Cl distances of 2.225(3) Å (Al2–Cl6) and 2.246(3)Å
3
(mcmip)AlCH (THF) [9]. In order to corroborate theses results, we ran
a similar reaction with triethyl aluminum and could, following the
same general procedure, isolate and characterize an analogous neutral
(
1
Al2–Cl5) and Al–O distances ranging from 1.944(5) Å (Al2–O6) to
.955(5) Å (Al2–O5 and Al2–O7), comparable to the distances found
in the literature for other [AlCl ]-fragment-containing ionic compounds
13]. The angles measured within the octahedron slightly diverge from
2 3
complex (mcmip)Al(CH CH )(THF), 2. The ORTEP diagram of com-
pound 2 is on the whole comparable to the structure reported by Lin
and co-workers [9] as it can be taken from Fig. 2 and will not be
discussed in detail in this contribution. Crystals of neutral aluminum
bisphenoxide 2 are also monoclinic, space group P2(1)/c (no. 14) [15].
Selected bonds and angles are listed in the Supplementary material.
Trying to elucidate the formation of the isolated ionic com-
pound 1 and to connect this to the already reported coordination
chemistry involving the mcmip ligand is quite complicated. Although
2
[
the ideal values with a Cl6–Al2–Cl5 angle of 178.90(13) and the differ-
ent perpendicular O(x)–Al–O(y) angles ranging from 88.5(2) to 91.3(2)
Å. The anion contains two bisphenoxides bound to the aluminum center
in such a way that the aluminum center is completely shielded by these
ligands. The different aluminum–oxygen distances are all within a
4 2 2
(Cl)
]+[Al(mcmip) ]−·2 THF, with atom-numbering scheme within the coordination sphere. Displacement ellipsoids are drawn at the 20%
Fig. 1. A perspective view of [Al(THF)
probability level, H atoms and crystal's THF molecules have been omitted.

J.K. Sypień et al. / Inorganic Chemistry Communications 30 (2013) 69–73
71
Fig. 2. A perspective view of Al(Et)(mcmip)(THF)], with the atom-numbering scheme. Displacement ellipsoids are drawn at the 20% probability level, H atoms have been omitted.
The ethyl group is disordered.
Lin and co-workers also reported a dinuclear, ionic aluminum
,2′-methylenebis(4-chloro-6-isopropyl-3-methylphenoxide), it was
obtained via a different route: the compound was isolated after
between NMR spectra of amorphous compound at RT and single crystal-
line compounds at −20 °C are obvious (see spectra in Supplementary
material) and ask for a temperature-dependant NMR-study of the
system. Unfortunately owing to the moisture sensitivity of the Al-
bisphenoxide and its limited solubility at low temperature, a satisfactory
NMR-study of this rearrangement has not been done thus far. However
first results point towards a formation of the ionic form of the complex
via ligand migration at low temperature. The formed ionic intermediate
remains in this form at room temperature for a while before hydrolysis
takes place, without intermediary formation of the initial neutral form
(see NMR spectra in Supplementary material).
The proposed interaction of two THF molecules with the alumi-
num center in solution (Scheme 2) instead of one single THF molecule
is likely to happen owing to the particular structure of the aluminum
mcmip-bisphenoxides: the steric hindrance of the methyl groups
present in the mcmip ligand produced the expected “twist” of the
bisphenol ligand and a divergence of the two isopropyl groups from
the aluminum center, leading to a wider coordination site and a pro-
nounced dynamic behavior of the related Al-bisphenoxide in solution,
as incidentally pointed out by Lin [9].
2
purposely adding trimethyl aluminum to the neutral (mcmip)
+
Al(CH
3
)(THF) and consisted of a cationic [Al(CH
3
)
2
(THF)] specie and
−
an anionic [(mcmip)(CH
)
3 2
Al] bridged by the bisphenoxo ligand [9].
Generally the reaction of Lewis bases (e.g. THF) with aluminum chloride
or its organometallic alkyl derivatives (Et AlCl or EtAlCl ) results in
2
2
a dissociation of initial dimeric species. A symmetrical dissociation
affords neutral donor–acceptor adducts of the type (L)(L′)(L″)Al(THF)
whereas the less common unsymmetrical dissociation yields, via a re-
distribution of the ligands, complex ionic species [13,16,17]. Theoretical
studies dealing with the structure of organometallic aluminum deriva-
tives with dimethyl ether showed that the most stable structure for
diethyl aluminum chloride is a chloro-bridged dimer, Et
which, upon addition of neutral O-donors, rearrange to form neutral spe-
cies of the type Et AlCl(L) [18]. In our case, a similar neutral starting com-
pound, Et AlCl(THF), would react with 2,2′-methylenebis(4-chloro-
-isopropyl-3-methylphenol) to form an initial neutral specie,
mcmip)(Cl)Al(THF) (Scheme 2). This is supported by NMR data
2 2
AlCl//ClAlEt
2
2
6
(
n
of compound 1 (amorphous powder in THF-D8) recorded at room
temperature [19], which strikingly displays the same patterns as found
in the case of a neutral aluminum bisphenoxide like, e.g. (mcmip)
The reaction pathway described in Scheme 2 can be compared to the
one proposed in studies of Derouault and co-workers dealing with the
reaction of AlCl
solutions of AlCl
THF, as well as the ionic complex [AlCl
the penta-coordinated adduct AlCl ·2 THF [17a]. Considering the alumi-
3
with THF. Derouault's work stated that saturated THF
contain neutral adducts, like AlCl ·THF and AlCl ·2
] formed from
3
AlCH (THF) [9] or compound 2 (see Supplementary material). The for-
3
3
3
−
+
mation of the isolated ionic specie at low temperature can be tentatively
explained by an intermolecular rearrangement of the initially formed
neutral chloro-aluminum bisphenoxide-THF complex. The differences
4 2 4
][AlCl (THF)
3
num bisphenoxides, the presence of an equilibrium involving diverse
-
OH
OH
O
O
O
O
-
4 C H
2
6
Low. Temp.
+
2
Et2Al-Cl
+
2
Al Cl . 2 THF
Al
2 4
+ [AlCl (THF) ]
THF
O
O
Scheme 2. Formation of the aluminum mcmip-phenoxides from diethyl aluminum chloride and the related bisphenol.

72
J.K. Sypień et al. / Inorganic Chemistry Communications 30 (2013) 69–73
chloro-bridged, bisphenoxo-bridged and bisphenoxo-chloro bridged
dimers is probably the reason for the formation of the ionic complex
Table 1
Test of the aluminum mcmip bisphenoxides in the copolymerization of cyclohexene
oxide with CO
2
.
(
Scheme 3). The bisphenoxo-chloro bridged dimers would rearrange
and undergo a cleavage similar to the unsymmetrical dissociation
found in AlX derivatives to eventually yield, with the assistance of
Yield %a % CO
linkages
note [22]
3
n w n
M g/mol PDI: M /M
3
THF, the isolated ionic aluminum bisphenoxide.
Compound
Exp. conditions: 20 ml cyclohexene oxide:
.198 mol; catalyst:epoxide molar ratio 1:300;
ca. 25 g CO i.e. CHO:CO molar ratio ca. 1:3;
P: 80 bar at 100 °C; reaction time ca. 15 h.
0
Generally speaking, the formation of this ionic aluminum
bisphenoxide is quite unusual if one consider that the majority of
the ionic aluminum complexes reported in the literature [9,14b,20]
require the use of a supplementary reagent to “derivatize” a neutral
aluminum complex. Only few examples of a spontaneous formation
of an ionic aluminum complex via rearrangement are reported,
like the report of Darensbourg and co-workers dealing with the
2
2
1
2
58
70
24
15
12
12
10,160
10,250
15,220
2.47
2.41
1.92
b
[
(THF)Al(C
ref 6b]
2
H
5
)(mbpcp )]
2
[
c
[(THF)Al(Cl)(mdtbp )]
52
17.4
9951
1.85
[
ref 6a]
catalyst:epoxide molar ratio
:1000
reaction of AlCl
borate. In that case, instead of isolating the desired mononuclear com-
pound, [{η -HB(3-Phpz) }AlCl ], a crystalline dinuclear ionic compound
resulting from redistribution process and rearrangement of the ligand
was characterized: [{η -HB(3-Phpz) (5-Phpz)} Al][AlCl ] [21].
3
with potassium hydrotris(3-phenylpyrazol-1-yl)
1
3
3
2
d
[
(THF)Al(Cl)(mmcp )] [ref 6a] 64
catalyst:epoxide molar ratio
1:1000
21.4
8332
2.3
3
2
2
4
Within a broad screening for new copolymerization catalysts
a
100% yield stands for a complete conversion of the epoxide into a copolymer having
1
[
6, see Supplementary material for exp. details], complexes 1 and 2
the actual percentage of carbonate linkages assessed via H NMR.
b
mbpcp=2,2′-methylene-bis(4-chlorophenol).
mdtbp=2,2′-methylene-bis(4,6-ditertbutyl phenol).
mmcp=2,2′-methylene-bis(4-methyl-2-(1-methylcyclohexyl) phenol).
were found to catalyze effectively the formation of aliphatic poly-
ether-carbonates using cyclohexene oxide as substrate.
c
d
The yields summarized in Table 1 are reasonably high (11.1 g
polymer with 1 and 13.4 g polymer with 2, ca. 58% and 70% yield
respectively), whereas the carbon dioxide insertion remains low (12
and 15% carbonate linkages in the copolymer for both aluminum com-
pounds under the given experimental conditions [22]). The chain lengths
are moderate and the polydispersity indexes rather high: around
to related 4,6-disubstituted aluminum 2,2′-bisphenoxides studied
within this project [6], 1 and 2 produced copolymers in good yields
with similar carbonate amounts, nevertheless with higher polydispersity
indexes. This fact together with a necessary higher catalyst loading
(optimal loading 1:300 instead of 1:1000) lowers somewhat their
10,160 g/mol in the case of the ionic compound and 10,250 g/mol for
the neutral one. Interestingly the isolated polymers display in both
cases similar chain lengths and polydispersity indexes (Mw/Mn=2.47
and 2.41 resp.). Considering that we inject the catalysts at room temper-
usefulness as CO
2
/epoxide-copolymerization catalysts.
More work is currently in progress to understand the formation
+
−
4
of [Al(THF) (Cl)
2
] [Al(mcmip)
2
]
from the neutral form and assess
ature as inert CH
2
Cl
2
solutions in the reactor (from an amorphous
its irreversibility. This ongoing study should also help to better un-
derstand the parameters ruling the formation of ionic bisphenoxo-
aluminates and to extend their use as catalyst in different polymeriza-
tion reactions.
powder for 1 and microcrystalline solid for 2), we most probably deal
in both cases with neutral forms of the Al-bisphenoxides and hence get
a similar reactivity. In addition the dynamic behavior of the mcmip
ligand together with a broader coordination site at the aluminum center
seems, generally speaking, to be rather counterproductive for controlled
copolymerization reactions. 13C NMR spectra of the copolymers under-
line this fact by showing a broad signal in the carbonate region, around
Acknowledgment
The authors are thankful for financial support from the program
“Efficient Energy Conversion and Use” of the Helmholtz Association
of National Research Centres. This work was also supported by the
German Federal Ministry of Education and Research within the context
1
54.8 ppm. This is probably due to an overlapping of syndiotactic and
isotactic carbonates' signals which is symptomatic of statistical polymers
23]. Comparing the 3,4,6-trisubstituted aluminum 2,2′-bisphenoxides
[
THF
THF
Al
THF
THF
THF
Al
Cl
THF
Al
O
O
O
O
Cl
O
Al
O
O
O
O
Al
Al Cl
Cl
O
THF
O
THFO
Cl
THF
Cl
THF
THF
THF
two alkoxo bridges
two chloride bridges
one alkoxo and one chloride bridge
Ligand migration
O
THF
THF
O
THF
Al
O
Cl
O
THF
Cl
Cl
Al
Al
Al
O
THF
O
Cl
O
THF
O
THFTHF
ionic complex
4 2 2
Scheme 3. Proposal for a ligand exchange leading to the final ionic aluminum bisphenoxide, [Al(THF) (Cl)
]+[Al(mcmip) ]−·x THF.

J.K. Sypień et al. / Inorganic Chemistry Communications 30 (2013) 69–73
73
disordered); molar mass: 1251.19 g/mol; colourless crystal, size: 0.4×0.35×
.25 mm; CCDC no. 292017; crystal system: monoclinic, space group, P2(1)/n (No.
4); temp=293(2)K; wavelength=0.71073 Å; a=12.4402(7) Å, b=24.6826(13)
of a “Sonderforschungsbereich” with the University of Heidelberg (SFB
23). Finally the authors want to thank the reviewers for some valuable
suggestions.
0
1
6
3
Å, c=22.2765(12)Å, α=γ=90.00°, β=91.8210(10), V=6836.7(6) Å ; Z=4;
density (calc.)=1.216 Mgm− ; abs. coeff.=0.327 mm ; F(000)=2656; total no.
of reflections=82505; number of independent reflections: 16794; θ range [°]: 1.23
to 28.29; (h, k, l) ranges: −16b=hb=16; −32b=kb=32; −29b=lb=29;
GOF (F2): 1.002; R indices: [I>2σ(I)]=0.0978, R indices (all data)=0.2694; Largest
e-max, e-min, [eǺ− ]: 1.754 and −0.608.
3
−1
Appendix A. Supplementary data
3
Supplementary data to this article can be found online at http://dx.
doi.org/10.1016/j.inoche.2013.01.021.
[
[
[
13] a) R. Sluka, M. Necas, P. Sindelar, Acta Crystallogr. E E60 (2004) M447;
b) A.H. Cowley, M.C. Cushner, R.E. Davis, P.E. Riley, Inorg. Chem. 20 (1981) 1179.
14] C.-H. Lin, L.-F. Yan, F.-C. Wang, Y.-L. Sun, C.-C. Lin, J. Organomet. Chem. 587 (1999) 151;
b) B.-T. Ko, Y.-C. Chao, C.-C. Lin, Inorg. Chem. 39 (2000) 1463.
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2 3
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[
[
[
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3
Å, α=γ=90.00°,− β=112.3650(10), V=2702.2(4) Å ; Z=4; density
3
−1
(calc.)=1.242 Mgm ; abs. coeff.=0.298 mm ; F(000)=1072; total no. of re-
flections=19742; Number of independent reflections: 6572; θ range [°]: 1.85 to
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(F2): 1.006; R indices [I>2σ(I)]=0.0595; R indices (all data)=0.1460; Largest
e-max, e-min [eǺ− ]: 0.612 and −0.428.
3
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Sulfur 19 (1984) 285.
6] a) T.A. Zevaco, J. Sypień, A. Janssen, O. Walter, E. Dinjus, Catal. Today 115 (2006) 151;
b) id J. Organomet. Chem. 692 (2007) 1963.
7] a) E. Grenet, FR 2 598 615 A1, 1986.
b) G. Lejeune, C. Nouvel, DE 3 634 989 A1, 1988.
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8] S. Rantsordas, M. Perrin, A. Thozet, Acta Crystallogr. 4 (1978) 1198.
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10] V.O. Aliyev, A. Abu-Raqabah, F. Al-Khodairi, A.H. Azizov, A.A. Khanmetov, B.V. Guliyev,
R.V. Aliyeva, C.K. Rasulov, M.J. Ibrahimova, WO 2007090412 A2, 2007; id. US
[
[
1
[19] See also sup. Mat. H NMR: δ (ppm) at RT: 1.17, 1.16 (6.78 Hz methyls of i-Pr);
2.07 (THF, CH
2
in β-location of O); 2.35 (Methyls at C3,3′); 3.26 (6.78 Hz
_);
in α-location of O); 7.07 (C5,5′-H); C NMR in THF D8, δ
(ppm)=16.94 ppm (methyls at C3); 24.38, 23.64 (methyls of the i-Pr), 24.5
(THF, CH in beta-location of O), 27.9 (methines of the iPr), 29.1 (_CH -bridge),
69.6 (THF, CH in alpha-location of O), aromatic region: C_H: 124.0, quaternary:
124.9; 128.2 131.8, 137.7 and 156.9 ppm
methines of the iPr); 4.05 and 3.98 (broad singlets, 1+1 H, _CH
4.18 (THF, CH
2
2
1
3
[
[
[
[
2
2
2
2
010152398 (A1).
11] The X-ray analyses were performed using a Siemens SMART CCD 1000 diffrac-
tometer with an irradiation time of 10 s to 20 s per frame, thus collecting a full
sphere of data using an ω-scan technique with Δω ranging from 0.3 to 0.45°.
The data were corrected for Lorentz and polarisation effects. An experimental
absorption correction has been performed using SADABS (Siemens area detector
absorption correction programme, 1997). The structures were solved with direct
methods and refined against F2 using “SHELX-97” (G. M. Sheldrick, Universität
Göttingen, 1997) und “XPMA” (L. Zsolnai, G. Huttner, Universität Heidelberg,
[20] a) J. Lewinski, P. Horeglad, M. Dranka, I. Justyniak, Inorg. Chem. 43 (2004) 5789;
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c) M. Bruce, V.C. Gibson, C. Redshaw, G.A. Solan, A.J.P. White, D.J. Willams,
J. Chem. Soc. Chem. Commun. (1998) 2523;
d) S. Dagorne, L. Lavanant, R. Welter, C. Chassenieux, P. Haquette, G. Jaouen,
Organometallics 22 (2003) 3732.
[21] D.J. Darensbourg, E.L. Maynard, M.W. Holtcamp, K.K. Klausmeyer, J.H. Reibenspies,
Inorg. Chem. 35 (1996) 2682.
1994). Crystallographic data of the structures have been deposited at the
[22] The integration ratio between methines of the polycarbonates units (i(PC) @
4.7 ppm) and the polyether units (i(PE) @ 3.4 ppm) indicates how efficient the
Cambridge Crystallographic Database Centre (CCDC), supplementary publications
Nos. CCDC 292017 (1) and 634159 (2). Copies of this information may be obtained
free of charge from: the Director, CCDC, 12 Union Road, Cambridge CB2 1EZ, UK
2 3
CO -insertion was; % carbonate linkages (%CO )=100x(i(PC)/[i(PC)+i(PE)]). The
rest of the aliphatic backbone (methylene groups) produces broad signals in the
range 1.2–2.2 ppm.
(Fax: +44-1223-336033, e-mail: deposit@ccdc.cam.ac.uk or www: http://www.
ccdc.cam.ac.uk). Figures were prepared with the appropriate software of the CCDC,
MERCURY 3.0 (Build RC5) for Windows (http://www.ccdc.cam.ac.uk/mercury).
[23] a) K. Nakano, K. Nozaki, T. Hiyama, Macromolecules 34 (2001) 6325;
b) M. Cheng, N.A. Darling, E.B. Lobkovsky, G.W. Coates, Chem. Commun. 20
(2000) 2007.
+
−
[
12] Crystallographic details for
1 [Al(THF) (Cl) ] [Al(mcmip) ] ·1.1THF: empirical
2 4 2
formula C62.40 Cl 9.10 (cryst. with 1.1 molecule THF per unit: 0.5+0.66
H
88.80Al
2
6
O