Structural Similarity in a Series of Alkali Metal Aluminates with Heteroleptic tert-Butoxide–Isobutyl Ligand Sets

Article abstract of DOI:10.1002/ejic.202000434

With the aim of increasing the number of well-defined alkali metal aluminates, six new crystalline examples containing heteroleptic tert-butoxide – isobutyl ligand sets are reported. NMR spectroscopic studies in C₆D₆ solution have determined their common general formula [(iBu)₂Al(OtBu)₂AM·(D)], where AM = Li, D = 2 THF, TMEDA or PMDETA; AM = Na, D = TMEDA or PMDETA; and AM = K, D = PMDETA. X-ray crystallographic studies show that despite the different sized alkali metals involved all six complexes adopt a common dinuclear motif with [AlO(AM)O] ring cores. Though Al–OtBu–Li linkages are common, the heavier alkali metal examples reported here are exceptionally rare. These structures could be interpreted as co-complexes between monomeric forms of tBuO(AM) and (iBu)₂Al(OtBu).

Full text of DOI:10.1002/ejic.202000434

European Journal of Inorganic Chemistry
Accepted Article
Title: Structural Similarity in a Series of Alkali Metal Aluminates with
Heteroleptic t-Butoxide – iso-Butyl Ligand Sets
Authors: Michael T. Whitelaw, Alan R. Kennedy, and Robert E. Mulvey
This manuscript has been accepted after peer review and appears as an
Accepted Article online prior to editing, proofing, and formal publication
of the final Version of Record (VoR). This work is currently citable by
using the Digital Object Identifier (DOI) given below. The VoR will be
published online in Early View as soon as possible and may be different
to this Accepted Article as a result of editing. Readers should obtain
the VoR from the journal website shown below when it is published
to ensure accuracy of information. The authors are responsible for the
content of this Accepted Article.
To be cited as: Eur. J. Inorg. Chem. 10.1002/ejic.202000434
Link to VoR: https://doi.org/10.1002/ejic.202000434
0
1/2020

European Journal of Inorganic Chemistry
10.1002/ejic.202000434
FULL PAPER
Structural Similarity in a Series of Alkali Metal Aluminates with
Heteroleptic t-Butoxide – iso-Butyl Ligand Sets
Michael T. Whitelaw, Alan R. Kennedy, and R. E. Mulvey*[a]
Dedicated to the memory of the late Professor Hans J. Reich
[
a]
Mr. M. T. Whitelaw, Dr. A. R. Kennedy, Prof. Dr. R. E. Mulvey
WestCHEM, Department of Pure and Applied Chemistry
University of Strathclyde
2
95 Cathedral Street
Glasgow G1 1XL
U.K.
E-mail: r.e.mulvey@strath.ac.uk
https://www.strath.ac.uk/staff/mulveyrobertprof/
Supporting information for this article is given via a link at the end of the document.
Abstract: With the aim of increasing the number of well-defined alkali
metal aluminates, six new crystalline examples containing
heteroleptic t-butoxide – i-butyl ligand sets are reported. NMR
hydroboration and hydrophosphination of unsaturated organic
molecules (e.g., aldehydes, ketones, alkenes, alkynes).24-26 In
stoichiometric synthesis we have shown that synergistic reactivity
can even be achieved when the lithium and aluminium species
are initially separated. This has been exploited in arene
deprotonation reactions where the base LiTMP (TMP is 2,2,6,6-
tetramethylpiperidide) works effectively only when the trap i-
spectroscopic studies in C
6
D
6
solution have determined their common
AM.(D)], where AM = Li, D = 2 THF,
general formula [(i-Bu) Al(OBu-t)
2
2
TMEDA or PMDETA; AM = Na, D = TMEDA or PMDETA; and AM =
K, D = PMDETA. X-ray crystallographic studies show that despite the
different sized alkali metals involved all six complexes adopt a
common dinuclear motif with [AlO(AM)O] ring cores. Though Al–OBu-
t–Li linkages are common, the heavier alkali metal examples reported
here are exceptionally rare. These structures could be interpreted as
co-complexes between monomeric forms of t-BuO(AM) and (i-
Bu AlTMP is introduced, in a tandem process referred to as
2
“trans-metal-trapping” to distinguish it from the common practice
of transmetallation.27-29
The primary aim of this present study was to add more stock to
the library of well-defined bimetallic alkali metal aluminium
compounds in a systematic manner, focusing on alkali metal
aluminium co-complexes with heteroleptic t-butoxide – i-butyl
ligand sets. Ligand choice was motivated by the commercial
Bu) Al(OBu-t).
2
Introduction
availability of tri-iso-butylaluminium (i-Bu Al), one of the most
3
Organoaluminium chemistry has long been studied in both
academic and applied research, the fruits of which have resulted
in important applications across different sectors of technology.1-
widely used organoaluminium reagents in chemistry, and by the
track record of the t-butoxide ligand in synergistic bimetallic
chemistry, the best known example being the classic Lochmann-
Schlosser superbase (LICKOR, commonly a mixture of n-BuLi
and t-BuOK).30-34 Herein, we report the synthesis and
characterisation of six such heteroleptic alkali metal aluminates.
To our surprise, prior to this work there are no such aluminates
having crystal structures containing (alkyl)Al-OBu-t-AM linkages,
where AM is Na or K, and only two examples when AM is Li.
8
This is underscored by the fact that trimethylaluminium, Me
is the World record holder for the most common organometallic
compound produced commercially in terms of tonnage. For
3
Al,
9
example, trimethylaluminium finds use in producing
methylaluminoxane (MAO),10,11 an important activator for Ziegler-
Natta catalysis,12 and in the synthesis of Tebbe’s reagent; a
mixed-metal compound for methylation of carbonyl compounds,13
and as an activator for an iron pre-catalyst in the oligomerisation
of ethene.14 Aluminium’s attributes, such as high natural Results and Discussion
abundance (the highest of any metal in the earth’s crust),
relatively low toxicity compared to that of precious metals, and
inexpensive cost,15 have become even more appealing recently
since there is a growing movement to develop more sustainable,
more environmentally benign synthetic and catalytic processes.
The development and fundamental study of well-defined
organoaluminium compounds is therefore currently undergoing a
resurgence.8, 16-22
There are several reported methods for synthesising
heterobimetallic aluminium alkoxides. These include reaction of
pre-formed lithium aluminates with a parent alcohol,35 reaction of
a pre-formed aluminium alkoxide with n-BuLi,36 lithiation of a
parent alcohol and reaction of the generated lithium alkoxide in
turn with either an alkyl aluminium or aluminium alkoxide
reagent,37 or reaction of a parent alcohol with the base LiAlH
In 2002, Gordon and Watkin successfully synthesised two mixed-
metal samarium-aluminium alkoxides on reacting i-Bu Al with
Sm(HMDS) (HMDS 1,1,1,3,3,3-hexamethyldisilazide,
[N(SiMe ]), followed by the addition of alcohol (i-PrOH or t-
4.38
Our specific interest in this resurgence overlaps with our general
interest in synergistic alkali-metal-mediated synergistic effects in
polar main group organometallic chemistry, the subject of a recent
review article.23 This work has resulted in the synthesis of
bimetallic lithium organoaluminate complexes that have found
application as catalysts/co-catalysts in homogeneous catalytic
3
3
=
3)2
BuOH).39 Crystals obtained from these reactions showed the
products to be mixed-metal dinuclear alkoxides with two alkoxide
bridges (Scheme 1).
1
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000434
FULL PAPER
Scheme 1. Procedures carried out for i) the synthesis of various alkoxy-bridged
samarium aluminates and ii) the synthesis of various tert-butoxy-bridged alkali-
metal aluminates.
Significantly, in this method, two i-butyl groups remain attached to
the f-block metal even under an excess of alcohol, so as our target
was mixed i-butyl – t-butoxide complexes, we decided to use a
modified version of the Gordon and Watkin method. Popular utility
amide reagents, alkali metal (AM) HMDS compounds (AM = Li,
Na, K)40-47 replacing the lanthanide HMDS reagent were each
mixed with i-Bu Al and t-BuOH in a 1:1:2 stoichiometric ratio in
3
toluene solution. Removal of the solvent in vacuo left a viscous oil
residue, which was then suspended in hexane to which a
stoichiometric quantity of a Lewis base donor ligand [THF,
TMEDA (N,N,N’N’-tetramethylethylenediamine or PMDETA
Figure 1. Molecular structures of (1) – (6) with key atom labelling. H atoms have
been removed for clarity.
(
N,N,N’,N”N”-pentamethyldiethylenetriamine)]
Crystals suitable for X-ray crystallographic studies were obtained
from six of these reactions producing [(i-Bu) Al(OBu-t) Li.(THF)
[(i-Bu) Al(OBu-t) Li.(TMEDA)] 2, [(i-Bu) Al(OBu-
Li.(PMDETA)] 3, [(i-Bu) Na.(TMEDA)] 4, [(i-
Bu) Al(OBu-t) Na.(PMDETA)] and [(i-Bu) Al(OBu-
t)
crystals, these new compounds were isolated in yields of 74%,
2%, 54% 32%, 48% and 34%, respectively. Since the
was
added.
Table 1. Selected bond lengths (Å) of structures (1) – (6).
2
2
2]
1
t)
,
2
2
2
(1)[a], [d]
(2)[a], [e]
(3)[a], [f]
(4)[b], [e]
(5)[b], [f]
(6)[c], [f]
2
2
Al(OBu-t)
2
Al1 – C1
1.991(2)
1.9963(14)
2.0027(17)
1.9994(13)
2.019(5)
2
2
5
2
Al1 – C2
Al1 – O1
Al1 – O2
M1 – O1
M1 – O2
M1 – D3
M1 – D4
M1 – D5
2.022(15)
1.7943(15)
1.7953(18)
1.931(4)
1.916(4)
1.947(4)
1.946(4)
–
1.9975(16)
1.8024(10)
1.7975(10)
1.976(3)
1.941(3)
2.208(3)
2.202(3)
–
1.9951(17)
1.8037(11)
1.7970(11)
1.958(3)
1.949(3)
2.165(3)
2.235(3)
–
1.9898(14)
1.7920(9)
1.7874(9)
2.2442(9)
2.2384(9)
2.4455(12)
2.4499(13)
–
2.003(5)
1.796(4)
1.787(3)
2.398(4)
2.293(4)
2.550(5)
2.781(4)
2.565(5)
2
K.(PMDETA)] 6. All air- and moisture-sensitive colourless
5
composition of each product 1 – 6 matched the stoichiometry
within the solution starting mixture, these reactions can be
categorised as two-fold deprotonations, with AM(HMDS)
deprotonating one alcohol molecule and one arm of i-Bu Al
3
deprotonating the other molecule (the latter in concurrence with
the reactivity observed by Gordon and Watkin), producing the
target alkali metal aluminium complex and a co-product of
HMDS(H) or i-butane respectively. Determined by X-ray
crystallographic studies, the molecular structures of all six
compounds 1– 6 are shown together in Figure 1. Since all
structures share related dinuclear motifs, selected analogous
bond lengths and bond angles are compared in Tables 1 and 2,
respectively.
[
[
a] M = Li, [b] M = Na, [c] M = K, [d] D = THF (O3, O4), [e] D = TMEDA (N3, N4),
f] D = PMDETA (N3, N4, N5)
Table 2. Selected bond angles (°) of structures (1) – (6).
(1)[a], [d]
(2)[a], [e]
(3)[a], [f]
(4)[b], [e]
(5)[b], [f]
(6)[c], [f]
C1-Al1-C2
C1-Al1-O1
C1-Al1-O2
C2-Al1-O1
C2-Al1-O2
110.5(4)
115.22(8)
112.45(9)
106.7(4)
120.6(3)
117.09(7)
109.41(5)
113.08(6)
110.02(6)
112.98(6)
116.12(7)
112.73(6)
108.91(6)
110.53(6)
114.98(6)
117.16(6)
109.63(5)
113.32(5)
108.31(5)
111.78(5)
114.0(2)
112.1(2)
108.10(18)
115.5(2)
110.59(19)
2
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000434
FULL PAPER
Inspecting the dimensions of the new structures, the terminal Al-
C(i-Bu) bonds show little variation across all six structures
spanning the narrow range [1.9898(14) – 2.022(15) Å]. Similarly,
the bridging Al-O bonds are nearly all the same length [range:
O1-Al1-O2
Al1-O1-M1
Al1-O2-M1
O1-M1-O2
O1-M1-D3
O1-M1-D4
O1-M1-D5
O2-M1-D3
O2-M1-D4
O2-M1-D5
D3-M1-D4
D3-M1-D5
D4-M1-D5
89.85(7)
93.22(12)
93.68(13)
82.44(16)
116.7(2)
117.11(19)
–
91.16(5)
92.61(8)
93.93(8)
82.07(10)
121.40(12)
126.41(13)
–
90.93(5)
93.19(9)
93.70(9)
82.16(11)
120.99(15)
127.11(14)
–
94.05(4)
96.83(4)
97.18(4)
71.50(3)
129.52(4)
131.93(4)
–
94.73(16)
95.79(15)
99.78(15)
68.34(12)
107.60(15)
175.52(16)
110.80(15)
117.74(15)
115.95(15)
117.01(16)
69.57(15)
121.24(17)
68.84(16)
1.7821(16) – 1.8037(11) Å ]. This pattern is consistent with the
stronger Lewis acidity of the trivalent Al centre, pulling the ligands
to their preferred bonding length irrespective of which alkali metal
is partnering them. As expected, the AM-O bridge lengths reflect
the size of the alkali metal. The Li-O bond lengths [range: 1.916(4)
–
1.976(3) Å] are influenced by the Lewis base donor strength,
with the weakest donor THF in 1 leading to the shortest Li-O
bridge lengths (average: 1.923 Å), while those involving the
bidentate and pseudo-bidentate nitrogen donor ligands have near
identical average lengths [1.958 Å and 1.953 Å for 2 and 3,
respectively]. Interestingly, the space around the Li centre is more
cramped with bidentate TMEDA, leading to more asymmetry in
the Li-O bridge bonds in 2 ( Li-O bond lengths, 0.035 Å; cf., 0.009
Å for 3). Coordination number differences account for the shorter
Na-O bonds in 4 compared to those in 5. The four-coordinate Na
in 4 has an average Na-O bond length of 2.241 Å, whereas with
the five-coordinate Na in 5 it increases to 2.345 Å. The potassium
aluminate 6 adopts the same basic architecture as 5, though the
presence of the heavier alkali metal extends the average M-O
bond length to 2.637 Å. This is a factor in the irregularity of the
aforementioned four-membered (AlOMO) rings getting more
pronounced with the increasing size of the alkali metal, as
reflected in the decreasing trend observed in the OMO bridge
angle [82.44(16), 82.07(10), 82.16(11), 71.50(3), and
120.0(2)
114.71(19)
–
127.20(13)
121.52(13)
–
123.15(14)
124.13(14)
–
130.30(4)
127.86(5)
–
105.32(18)
–
84.02(10)
–
84.67(11)
–
75.55(5)
–
–
–
–
–
[
[
a] M = Li, [b] M = Na, [c] M = K, [d] D = THF (O3, O4), [e] D = TMEDA (N3, N4),
f] D = PMDETA (N3, N4, N5)
The lithium structures (1) – (3) display essentially planar four-
membered (AlOLiO) rings with t-butoxide bridges. Each metal
centre occupies a distorted tetrahedral site with two terminal i-Bu
ligands completing the Al coordination and two donor atoms (from
two THF ligands, one TMEDA ligand and one PMDETA ligand in
60.21(5) for 1-6 (omitting 5), respectively].
1H and 13C NMR spectroscopic data were collected in C
6D
6
1
, 2, and 3 respectively) completing the Li coordination. The
solution for each complex (1) – (6). The H spectra of the lithium
1
bidentate coordination of Li by trifunctional PMDETA is unusual
though there are some precedents for it29, 48-51 in the Cambridge
Structural Database (CSD).52 The first sodium structure 4 closely
resembles that of 2, while the second sodium structure 5 also has
a (AlONaO) ring as in 4, but in contrast to the lithium congener 3
the PMDETA here uses its full complement of nitrogen donor
atoms, making the sodium atom penta-coordinate. Disorder in the
structure of 5 rules out an analysis of its dimensions, though its
connectivity is unequivocal. Moving to potassium in 6, the four-
membered (AlOKO) ring deviates from planarity though the
deviation is small (sum of endocyclic bond angles, 356.93), but
as in 5 PMDETA maintains its tridentate coordination to this larger
alkali metal meaning it also takes up a distorted trigonal
bipyramidal geometry in its penta-coordinate state. Atoms O1 and
N4 occupy the axial positions [bond angle of 172.05(5)] and O2,
N3 and N5 occupy the equatorial positions [bond angles of
aluminate complexes (1) – (3) showed characteristic i-butyl
resonances comprising a nonet, a doublet and a second doublet
at approximately 2.35, 1.41, and 0.38 ppm, respectively, with the
third resonance associated with the most electronegative CH
2
group directly attached to the Al centre. The chemical shifts of
these resonances do not move significantly in the sodium
aluminates 4 and 5 (approximately at 2.38, 1.44 and 0.35 ppm) or
the potassium aluminate 6 (2.43, 1.43 and 0.38 ppm). Consistent
with the single OBu-t environment in the crystal structures, a
sharp singlet is found at 1.38 ppm (approximately) for 1 – 3, 1.44
ppm (approximately) for
corresponding to the equivalent CH
different donor ligands in 1 – 6 all show their expected
4
and 5, and 1.45 ppm for 6,
arms of the OBu-t group. The
H NMR
3
1
resonances. Complexes (1), (2), and (4) all show six distinct
environments in the 13C NMR spectra, while complexes (3), (5),
and (6) all show eight distinct environments. This is one less than
would be expected for each structure (except for 3) as the
quadrupolar Al nucleus can broaden the signals of directly
118.68(6), 112.20(6) and 119.09(6)]. This strong structural
resemblance between the lithium, sodium and potassium
complexes is unusual in homometallic chemistry with the heavier
alkali metals often preferring higher states of association
attached groups, here the iso-butyl CH , often making them not
2
observable. This was proven through HSQC analysis (see
Supporting Information). In the case of 3, the asymmetrical nature
of the PMDETA ligand is not observable under the conditions
studied leading to fewer resonances than expected, suggesting
that the ligating nitrogen atoms are interchanging and making
(frequently polymeric) than their lighter congener due to their
greater availability of coordination space.53-55 The fact that such
similarity is present in these heterobimetallic structures can be
attributed to the greater Lewis acidity of aluminium, which dictates
the primary architecture of the structures, the tetrahedral ate
arrangement, leaving the alkali metals to fulfil their coordination
requirement through secondary interactions with the phenoxide
bridges and donor solvents.
both terminal Me N units appear equivalent on this timescale.
2
Clearly, on the basis of these data, the identity of the alkali metal
exerts little influence on the electronic nature of the contents of
the anionic aluminium coordination sphere as expected from the
similarities of the crystal structures. Complexes (1) – (3) show one
3
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000434
FULL PAPER
sharp resonance in the
7
Li NMR spectra at approximately 0.10, -
alkenes, and carbodiimides.24 In this catalyst the Li and Al centres
are connected by a P bridge.
0.25 and -0.23 ppm, respectively. Fully assigned NMR
spectroscopic data can be found in the Experimental Section.
Experimental Section
One could view the molecular structures of (1) – (6) superficially
and dismiss them as simple expected hetero-dinuclear
arrangements. However, it is interesting to ponder that they could
also be interpreted as a contacted ion-pair, co-complexes
General procedure: All reactions and manipulations were performed under
a protective argon atmosphere using standard glovebox techniques, or
under
a protective nitrogen atmosphere using standard Schlenk
between monomeric forms of (i-Bu)2Al(OBu-t) and t-BuO(AM).56,
techniques. Hexane, THF and toluene were dried by heating to reflux over
sodium benzophenone ketyl and then distilled under nitrogen prior to use.
57
These reactions could have alternatively produced a separated
mixture of these two components, but in all cases co-
complexation is preferred, no doubt supported by the additional
presence of the donor ligands that complete the coordination of
the alkali metals. Steric factors must also play a role given the
large sizes of the i-Bu and t-BuO ligands as a dimeric [(i-
C6D6 was degassed by freeze-pump-thaw methods and stored over
activated 4 Å molecular sieves. All reagents were purchased from
commercial sources and used as received, unless states otherwise.
TMEDA, PMDETA and HMDS(H) were distilled and stored over activated
4
Å molecular sieves prior to use. NMR spectra were recorded on a Bruker
AV3 or AV 400 MHz spectrometer operating at 400.13 MHz for H, 155.47
MHz for Li and 100.62 MHz for 13C. All 13C spectra were proton decoupled.
H, 13C{ H} and Li chemical shifts are expressed in parts per million (δ,
1
Bu)
2
Al(OBu-t)] structure would be more sterically crowded than
2
7
the mixed-metal structures. Though t-BuOLi can be considered a
pseudo-halide, the steric bulk and stereochemistry of its anionic
moiety precludes it from forming a salt-like lattice structure like
that of LiCl. Parent, unsolvated t-BuOLi displays an interesting
structural diversity in the crystalline state from a hexameric58 to
an octameric aggregate.59 This propensity to form molecular
structures linked to its good solubility in organic solvents makes t-
BuOLi an excellent co-complexing agent60-65 as evidenced most
importantly in the aforementioned Lochmann-Schlosser
superbase,34 though in that composition it is generated in situ from
n-BuLi and t-BuOK and exists in a co-complexed form. Though
having longer and weaker AM-O bonds than in t-BuOLi, both t-
BuONa in 4 and 5 and t-BuOK in 6 also co-complex with
1
1
7
ppm) and referenced to residual solvent peaks. HSQC measurements
were recorded on an AV 400 MHz spectrometer operating at 400.13 MHz,
using the pulse program hsqcedetgp. Data for compounds (1) – (6) were
collected on an Oxford Diffraction Gemini S instrument with graphite-
monochromated Cu Kα (λ 1.54184 Å) radiation. Data collection and
processing used CrysalisPro software.78 All structures were solved and
refined to convergence against F2 for all independent reflections by the full-
matrix least squares method using SHELXL-2014 implemented within
WINGX.79,80 All non-hydrogen atoms were refined using anisotropic
thermal parameters. Structure 5 was identified as a twinned sample post
data collection. The program ROTAX was used to generate a hklf5
formatted reflection file.81 Refinement using this file and as a two
component twin gave a superior model with BASF = 0.2398(33). Several
of the structures contained disordered fragments. All of these were
modelled with atoms split over two sites and with appropriate restraints
and constraints applied to ensure normal geometries and displacement
behaviours. Treated in such a way were; two butyl and two THF ligands of
1, a butyl ligand and the TMEDA ligand of 4, the ligands of one of the two
crystallographically unique complexes of 5 and, two of the butyl groups of
monomeric (i-Bu) Al(OBu-t) showing that these heavier alkali
2
metals retain oxophilic character. Searching the Cambridge
Structural Database (CSD) for complexes containing an Al–OBu-
t–Li fragment reveals 26 hits,66-72 which reduces to one result with
potassium and none at all with sodium, hence demonstrating the
relative rarity of the heavier alkali metal structures reported here.
Of the lithium examples, only one, the tris-alkoxide [(OBu-
6
. Selected crystallographic data are shown in Tables S1, S2 and S3 and
full details in cif format are available from CCDC (1999145 – 1999151).
t)[(Me
3
Si)
3
C]Al(OBu-t) Li.(THF)] has a similar dinuclear motif to
2
Synthesis of LiHMDS:82 To a solution of HMDS(H) (1.04 ml; 5 mmol) in
hexane (10 ml) was added nBuLi (1.6 M/hexane; 3.125 ml; 5 mmol). The
transparent, colourless solution was stirred at room temperature overnight
before the solvent was removed in vacuo, leaving a white solid material
that found here though it displays mono THF solvation in contrast
to the di THF solvation of 1.67 The one potassium example
[
Al
being a low valent aluminium alkoxide displaying a hybrid
structure between metalloid cluster and hypothetical
6
K
8
{Al(OBu-t)
3
} ] bears no resemblance to the structure of 6,
6
which was then isolated (0.831 g; 4.98 mmol; 99.5% yield).
MHz, C , 300 K): δ 0.126 (s, 18H, CH ) ppm. Li NMR (155.47 MHz,
, 300 K): δ 1.121 (s) ppm.
1H NMR (400.1
a
a
6D
6
3
7
C6D6
molecular Zintl phase.73 Note that low valent aluminium chemistry
is an area currently attracting increasing interest.18, 74-77
Synthesis of [(i-Bu)
2
Al(OBu-t)
2
Li.(THF)
2
], 1: To a solution of LiHMDS
(1 M/hexane;
.8 ml; 0.8 mmol) and this was stirred at room temperature for 1 hour. To
(0.1336 g; 0.8 mmol) in toluene (5 ml) was added Al(i-Bu)
3
0
this transparent, colourless solution was added t-BuOH (0.15 ml; 1.6
mmol) and this was stirred at room temperature overnight. After this, all of
the solvent was removed in vacuo, leaving behind a colourless but viscous
oil residue; this was resuspended in hexane (2 ml) and THF was added to
the white suspension (0.48 ml; 2.5 mmol). This was stored at -30 °C and
a crop of colourless block crystals were obtained after several hours.
Conclusion
This study has added several new well-defined alkali metal
organoaluminium alkoxide co-complexes to the library of such
compounds, the most significantly being, to the best of our
knowledge, the first crystallographically characterised heavier
alkali metal examples containing (alkyl)Al-OBu-t-AM linkages,
where AM is Na or K. Learning more about how alkali metal
complexes and organoaluminium compounds co-complex and
the structures that such co-complexes adopt will help the rational
development of new chemistry in areas such as homogeneous
catalysis. We recently demonstrated this idea with the report of
These were isolated by filtration (0.245 g; 0.592 mmol; 74% yield).
1
H NMR
of i-Bu); 1.326
of t-BuO); 1.418 (d,
of i-Bu); 2.358 (nonet, J = 6.60 Hz, 2H, CH of i-Bu);
.478 (m, J = 6.58, 8H, CH of THF) ppm. 13C{ H} NMR (100.6 MHz, C
00K): δ 24.99 (s, CH of THF); 27.18 (s, CH of i-Bu); 29.27 (s, CH
of t-BuO); 67.10 (s, C of t-BuO); 68.00 (s, CH of THF)
Li NMR (155.5 MHz, C , 300K): δ -0.102 (s) ppm.
(400.1 MHz, C
6D
6, 300K): δ 0.382 (d, J = 6.94 Hz, 4H, CH
2
(m, J = 3.32 Hz, 8H, CH
2
of THF); 1.382 (s, 18H, CH
3
J = 6.52 Hz, 12H, CH
3
3
2
1
6D6,
3
2
3 of i-
Bu); 33.48 (s, CH
ppm.
3
2
7
6D6
the lithium phosphidoaluminate i-Bu
functions as a catalyst for the hydrophosphination of alkynes,
3
AlPPh
2
Li(THF)
3
that
Synthesis of [(i-Bu)
2
Al(OBu-t)
2
Li.TMEDA], 2: To a solution of LiHMDS
(0.167 g; 1 mmol) in toluene (5 ml) was added Al(i-Bu)
3
(1 M/hexane; 1 ml;
4
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000434
FULL PAPER
1
mmol) and this was allowed to stir at room temperature for 1 hour. After
Synthesis of [(i-Bu)
2Al(OBu-t)
2K.PMDETA], 6: To a solution of KHMDS
this, t-BuOH was added (0.1875 ml; 2 mmol) and this transparent,
colourless solution was stirred at room temperature overnight. After this,
all of the solvent was removed in vacuo, leaving behind a colourless but
viscous oil residue; this was resuspended in hexane (2 ml) and TMEDA
was added to the white suspension (0.23 ml; 1.5 mmol). This was stored
at -30 °C and a crop of colourless block crystals were obtained after
several hours. These were isolated by filtration (0.213 g; 0.52 mmol; 52%
(0.199 g; 1 mmol) in hexane (5 ml) was added Al(i-Bu)3 (1 M/hexane; 1 ml;
1 mmol) and this was stirred at room temperature for 1 hour. To this, t-
BuOH was added (0.187 ml; 2 mmol) and the transparent, colourless
solution was allowed to stir at room temperature overnight. After this, all of
the solvent was removed in vacuo leaving a colourless but viscous oil. This
was re-suspended in hexane (2 ml) and PMDETA was added to the white
suspension (0.25 ml; 1.2 mmol); the now transparent, colourless solution
was stored at -30 °C and a crop of colourless crystals were present after
several hours. The crystals were isolated by filtration (0.169 g; 0.34 mmol;
yield).
of i-Bu); 1.386 (s, 18H, CH
i-Bu); 1.660 (s, 4H, CH of TMEDA); 1.897 (s, 12H, CH
nonet, J = 6.56 Hz, 2H, CH of i-Bu) ppm. 13C{ H} NMR (100.6 MHz, C
of i-Bu); 33.38 (s, CH
of TMEDA); 66.80 (s, C of
, 300 K): δ -0.256 (s) ppm.
1H NMR (400.1 MHz, C
6D
6, 300 K): δ 0.387 (d, J = 6.96 Hz, 4H, CH
2
3
of t-BuO); 1.411 (d, J = 6.55 Hz, 12H, CH
3
of
2
3
of TMEDA); 2.334
34% yield).
Bu); 1.453 (s, 18H, CH
3H, CH of PMDETA); 1.863 (m, 8H, CH
of PMDETA); 2.421 (m, 2H, CH of i-Bu) ppm. 13C{
, 300 K): δ 27.73 (s, CH of i-Bu); 29.54 (s, CH
of t-BuO); 41.48 (s, CH of PMDETA); 44.96 (s, CH
of PMDETA); 56.79 (s, CH of PMDETA); 66.48 (s, C of t-BuO)
1
H NMR (400.1 MHz, C
of t-BuO); 1.467 (m, 12H, CH
of PMDETA); 1.918 (s, 12H, CH
H} NMR (100.6 MHz,
of i-Bu); 34.29 (s, CH
of PMDETA); 55.41
6
D
6
, 300 K): δ 0.388 (m, 4H, CH
2 of i-
(
1
6D
6,
3
3
of i-Bu); 1.780 (m,
3
00 K): δ 26.68 (s, CH of i-Bu); 28.79 (s, CH
of TMEDA); 56.32 (s, CH
Li NMR (155.5 MHz, C
3
3
of t-
3
2
3
BuO); 46.13 (s, CH
t-BuO) ppm.
3
2
1
7
6D
6
C
6D
6
3
3
3
3
Synthesis of [(i-Bu)
2
Al(OBu-t)
2
Li.PMDETA], 3: To a solution of LiHMDS
(1 M/hexane; 1 ml;
mmol) and this was stirred at room temperature for 1 hour. To this, t-
(s, CH
ppm.
2
2
(0.167 g; 1 mmol) in toluene (5 ml) was added Al(iBu)
3
1
BuOH (0.1875 ml; 2 mmol) was added and this transparent, colourless
solution was allowed to stir at room temperature overnight. After this, all of
the solvent was removed in vacuo leaving a colourless but viscous oil. This
was resuspended in hexane (2 ml) before PMDETA was added to the
white suspension (0.31 ml; 1.5 mmol); the transparent solution was stored
at -30 °C and a crop of colourless block crystals were present after several
Acknowledgements
M.T.W. wishes to thank the University of Strathclyde for
sponsoring his PhD studentship through the award of a Research
Excellence Award (REA). Dr Stuart Robertson is also thanked for
drawing the ToC figure.
hours and were isolated by filtration (0.254 g; 0.54 mmol; 54% yield).
NMR (400.1 MHz, C , 300 K): δ 0.377 (d, J = 6.90 Hz, 4H, CH of i-Bu);
.400 (d, J = 6.61 Hz, 12H, CH of i-Bu); 1.415 (s, 18H, CH of t-BuO);
.018 (s, 3H, CH of PMDETA); 2.044 (s, 12H, CH of PMDETA); 2.101 (t,
of PMDETA); 2.174 (t, J = 5.67 Hz, 4H, CH of
1H
6D
6
2
1
2
3
3
3
3
Full crystallographic details of the mentioned compounds in .cif
J = 5.55 Hz, 4H, CH
PMDETA); 2.332 (nonet, J = 6.53 Hz, 2H, CH of i-Bu) ppm. 13C{
100.6 MHz, C , 300 K): δ 27.14 (s, CH of i-Bu); 29.32 (s, CH
3.94 (s, CH of t-BuO); 42.28 (s, CH
PMDETA); 56.57 (s, CH of PMDETA); 56.74 (s, CH
s, C of t-BuO) ppm. Li NMR (155.5 MHz, C , 300 K): δ -0.228 (s) ppm.
2
2
format are available from the CCDC (1999145 – 1999151).
1H} NMR
(
6D
6
3 of i-Bu);
3
3
3
of PMDETA); 46.26 (s, CH
3
of
Keywords: Alkali Metals • Aluminium • Ate Compounds •
Heterobimetallics • Solid-state Structures
2
2
of PMDETA); 67.42
(
7
6D6
Orcid
Synthesis of [(i-Bu)
2
Al(OBu-t)
2
Na.TMEDA], 4: To a solution of NaHMDS
(1 M/hexane; 2 ml;
mmol) and this was stirred at room temperature for 1 hour. To this, t-
(0.365 g; 2 mmol) in toluene (5 ml) was added Al(i-Bu)
3
A. R. Kennedy 0000-0003-3652-6015
R. E. Mulvey 0000-0002-1015-2564
2
BuOH was added (0.375 ml; 4 mmol) and this transparent, colourless
solution was allowed to stir at room temperature overnight. After this, all of
the solvent was removed in vacuo leaving a colourless but viscous oil. This
was resuspended in hexane (2 ml) and TMEDA was added to the white
suspension (0.3 ml; 2 mmol). The transparent solution was stored at -30 °C
and a crop of colourless block crystals were present after several hours;
[
1]
[2]
3]
K. Ziegler, in Advances in Organometallic Chemistry, ed. R. West,
F. G. A. Stone, Academic Press, 1968, vol. 6, pp. 1-16.
P. A. Chaloner, in The Chemistry of the Metal - Carbon Bond, ed. F.
R. Hartley, Wiley, 1987, vol. 4, ch. 4, pp. 411-467.
A. Salzer, C. Elschenbroich, in Organometallics: A Concise
Introduction, ed. B. G. Teubner, Wiley VCH, 1992, ch. 7.2, pp. 75-
85.
M. Witt, H. W. Roesky, Curr. Sci., 2000, 78, 410-430.
D. A. Atwood, A. Mitra, in Comprehensive Organometallic Chemistry
III, ed. R. H. Crabtree, D. M. P. Mingos, Elsevier, 2007, vol. 3, ch.
[
these were isolated by filtration (0.272 g; 0.64 mmol; 32% yield).
1
H NMR
of i-Bu); 1.393
of i-Bu); 1.613 (s,
of TMEDA); 2.376 (nonet, J =
H} NMR (100.6 MHz, C , 300 K): δ
of i-Bu); 34.13 (s, CH of t-BuO); 45.26
2 of TMEDA); 66.47 (s, C of t-BuO) ppm.
(
(
4
6
2
400.1 MHz, C
s, 18H, CH of t-BuO); 1.427 (d, J = 6.51 Hz, 12H, CH
of TMEDA); 1.766 (s, 12H, CH
.56 Hz, 2H, CH of i-Bu) ppm. 13C{
7.55 (s, CH of i-Bu); 29.35 (s, CH
of TMEDA); 56.37 (s, CH
6D6, 300 K): δ 0.393 (d, J = 6.99 Hz, 4H, CH2
3
3
[4]
[
5]
H, CH
2
3
1
6D6
3
.06, pp. 265-285.
3
3
[
[
[
6]
7]
8]
C. Fliedel, S. Dagorne, in Modern Organoaluminum Reagents, ed.
S. D. S. Woodward, Springer, 2012, vol. 41, pp. 125-171.
M. R. Mason, in Encyclopedia of Inorganic and Bioinorganic
Chemistry, Wiley, 2016.
(s, CH
3
Synthesis of [(i-Bu)
2
Al(OBu-t)
2
Na.PMDETA], 5: To a solution of NaHMDS
(1 M/hexane; 2 ml;
mmol) and this was stirred at room temperature for 1 hour. To this, t-
J. Li, Y. Liu, X. Ma, Z. Yang, H. W. Roesky, Coord. Chem. Rev.,
(0.365 g; 2 mmol) in toluene (5 ml) was added Al(i-Bu)
3
2
018, 374, 387-415.
2
[9]
T. Saito, H. Minami, C. Wang, M. Uchiyama, Angew. Chem. Int. Ed,
2015, 54, 4665-4668.
BuOH was added (0.375 ml; 4 mmol) and this transparent, colourless
solution was allowed to stir at room temperature overnight. After this, all of
the solvent was removed in vacuo leaving a colourless but viscous oil. This
was re-suspended in hexane (2 ml) followed by the addition of PMDETA
[
[
10]
J. Storre, A. Klemp, H. W. Roesky, H.-G. Schmidt, M. Noltemeyer,
R. Fleischer, D. Stalke, J. Am. Chem. Soc., 1996, 118, 1380-1386.
J. Storre, C. Schnitter, H. W. Roesky, H.-G. Schmidt, M.
Noltemeyer, R. Fleischer, D. Stalke, J. Am. Chem. Soc., 1997, 119,
7505-7513.
11]
(
3
0.46 ml; 2.2 mmol). The transparent, colourless solution was stored at -
0 °C and a crop of colourless block crystals were present after several
hours; these were isolated by filtration (0.46 g; 0.95 mmol; 48% yield).
[
[
12]
13]
E. Holzkamp, K. Ziegler, H. Breil, H. Martin, Angew. Chem. Int. Ed,
1
955, 16, 426.
1H
G. W. Parshall, F. N. Tebbe, G. S. Reddy, J. Am. Chem. Soc., 1978,
100, 3611-3613.
P.-A. R. Breuil, A. Boudier, L. Magna, H. Olivier-Bourbigou, P.
Braunstein, Dalton Trans., 2015, 44, 12995-12998.
A. Earnshaw, N. N. Greenwood, Chemistry of the Elements,
Butterworth-Heinemann, 2nd edn., 1997.
NMR (400.1 MHz, C
2H, CH of i-Bu); 1.449 (s, 18H, CH
CH of PMDETA); 1.995 (s, 12H, CH
i-Bu) ppm. 13C{
Bu); 29.54 (s, CH
PMDETA); 45.70 (s, CH
s, CH of PMDETA); 66.60 (s, C of t-BuO) ppm.
6D
6, 300 K): δ 0.332 (m, 4H, CH
2
of i-Bu); 1.412 (m,
1
3
3
of t-BuO); 1.816 (m, 11H, CH
2
and
[14]
3
3
of PMDETA); 2.379 (m, 2H, CH of
, 300 K): δ 27.39 (s, CH of i-
of t-BuO); 43.50 (s, CH of
of PMDETA); 55.60 (s, CH of PMDETA); 57.27
[
[
15]
16]
1H} NMR (100.6 MHz, C
6D6
3
of i-Bu); 34.32 (s, CH
3
3
X. Ma, W. Li, M. G. Walawalkar, Z. Yang, H. W. Roesky, Coord.
Chem. Rev., 2017, 350, 14-29.
3
2
(
2
5
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000434
FULL PAPER
[
[
[
17]
18]
19]
S. Sinhababu, M. K. Sharma, G. Mukherjee, G. Rajaraman, S.
Nagendran, Dalton Trans., 2017, 46, 7672-7676.
A. J. P. White, C. Bakewell, M. R. Crimmin, Angew. Chem. Int. Ed,
[65]
[66]
[67]
S. Fadlallah, L. Wang, C. Bellini, C. Orione, V. Dorcet, J.-F.
Carpentier, Y. Sarazin, Organometallics, 2015, 34, 1321-1327.
T. J. Boyle, W. J. Evans, J. W. Ziller, Polyhedron, 1992, 11, 1093-
1097.
W.-Y. Chen, A. G. Avent, C. Eaborn, I. B. Gorrell, P. B. Hitchcock,
J. D. Smith, Organometallics, 1996, 15, 4343-4345.
B. Neumüller, J. Pauls, Z. Anorg. Allg. Chem., 2000, 626, 270-279.
A. Schlegel, H. Nöth, M. Suter, J. Organomet. Chem., 2001, 621,
231-241.
2
018, 57, 6638-6642.
X. Ma, Q. Shen, W. Li, W. Liu, Y. Ding, Z. Yang, H. W. Roesky,
Chem. Eur. J., 2019, 25, 11918-11923.
N. Gupta, A. Dogra, ChemistrySelect, 2019, 4, 10452-10465.
M. Bhandari, S. Rawat, B. Prashanth, S. Singh, Chem. Cat. Chem.,
[
[
20]
21]
[68]
[69]
2
020, 12, 1-6.
[
[
22]
23]
A. D. Sadow, U. Kanbur, Chem. Eur. J., 2020, 26, 1-16.
M. Uzelac, R. E. Mulvey, S. D. Robertson, Chem. Rev., 2019, 119,
[70]
[71]
[72]
[73]
[74]
B. Neumüller, J. Pauls, Z. Anorg. Allg. Chem., 2001, 627, 2127-
2132.
P. König, M. Veith, A. Rammo, V. Huch, Angew. Chem. Int. Ed,
2005, 44, 5968-5971.
H. R. Simmonds, R. J. Less, D. S. Wright, Dalton Trans., 2014, 43,
5785-5792.
8
332-8405.
[
[
[
[
24]
25]
26]
27]
S. A. Orr, V. A. Pollard, R. McLellan, A. R. Kennedy, E. Hevia, R. E.
Mulvey, Chem. Commun., 2018, 54, 1233-1236.
M. Á. Fuentes, V. A. Pollard, A. R. Kennedy, R. McLellan, R. E.
Mulvey, Angew. Chem. Int. Ed, 2018, 57, 10651-10655.
A. Young, V. A. Pollard, R. McLellan, A. R. Kennedy, T. Tuttle, R. E.
Mulvey, Angew. Chem. Int. Ed., 2019, 58, 12291-12296.
M. Uzelac, R. McLellan, A. R. Kennedy, R. E. Mulvey, E. Hevia,
Angew. Chem. Int. Ed., 2017, 56, 9566-9570.
M. Uzelac, R. E. Mulvey, Chem. Eur. J., 2018, 24, 7786-7793.
E. Hevia, R. E. Mulvey, A. R. Kennedy, D. R. Armstrong, J. M. Gil-
Negrete, L. J. Bole, M. Uzelac, R. McLellan, Synthesis, 2019, 51,
N. Trapp, P. Henke, C. E. Anson, H. Schnöckel, Angew. Chem. Int.
Ed, 2010, 122, 3214-3218.
C. Cui, H. W. Roesky, H.-G. Schmidt, M. Noltemeyer, H. Hao, F.
Cimpoesu, Angew. Chem. Int. Ed., 2000, 39, 4274-4276.
S. Inoue, C. Weetman, Chem. Cat. Chem., 2018, 10, 4213-4228.
C. Weetman, P. Bag, S. Inoue, Angew. Chem. Int. Ed, 2018, 57,
14394-14413.
M. Garçon, C. Bakewell, R. Y. Kong, L. O'Hare, A. J. P. White, M.
Crimmin, ChemRxiv, 2019, Pre-Print.
CrysalisPro, Agilent Technologies Ltd, 2014, Yarnton, Oxfordshire,
[75]
[76]
[
[
28]
29]
[77]
[78]
1
207-1215.
[
[
[
[
30]
31]
32]
33]
M. Schlosser, J. Organomet. Chem., 1967, 8, 9-16.
M. Schlosser, Pure & Appl. Chem., 1988, 60, 1627-1634.
M. Janata, L. Lochmann, Cent. Eur. J. Chem., 2014, 12, 537-548.
M. Kaiser, P. Benrath, T. Limbach, M. Mondeshki, J. Klett, Angew.
Chem. Int. Ed, 2016, 55, 10886-10889.
England
[79]
[80]
[81]
G. M. Sheldrick, Acta. Cryst., 2015, C71, 3-8.
L. J. Farrugia, J. Appl. Cryst., 2012, 45, 849-854.
R. I. Cooper, R. O. Gould, S. Parsons, D. J. Watkin, J. Appl. Cryst.,
2002, 35, 168-174.
D. R. Armstrong, E. Herd, D. V. Graham, E. Hevia, A. R. Kennedy,
W. Clegg, L. Russo, Dalton Trans., 2008, 1323-1330.
[
[
[
34]
35]
36]
S. Kimpel, B. Jennewein, D. Thalheim, J. Klett, Chem. Eur. J. , 2018,
2
4, 7605-7609.
[82]
S. Kopf, A. J. Plajer, A. L. Colebatch, A. D. Bond, D. S. Wright, R.
García-Rodríguez, Dalton Trans., 2019, 48, 5692-5697.
R. F. Hernández-Campos, J. García-Ríos, F. Rascón-Cruz, V. A.
Moreno-Martínez, R. Huerta-Lavorie, M.-A. Velázquez-Carmona, R.
Cea-Olivares, D. Martínez-Otero, V. Jancik, RSC. Adv., 2015, 5,
9
9722-99731.
[
37]
T. Muñoz, M. Palenzuela, J. F. Vega, A. Gutiérrez-Rodríguez, T.
Cuenca, M. E. G. Mosquera, Dalton Trans., 2019, 48, 6435-6444.
D. A. Atwood, M. S. Hill, Main Group Chemistry, 1998, 2, 285-292.
J. C. Gordon, G. G. Giesbrecht, D. L. Clark, B. L. Scott, J. G. Watkin,
K. J. Young, Inorg. Chem., 2002, 41, 6372-6379.
[
[
38]
39]
[
[
40]
41]
M. Westerhausen, Coord. Chem. Rev., 1998, 176, 157-210.
P. Power, M. Lappert, A. Protchenko, A. Seeber, Metal Amide
Chemistry, Wiley, 2009.
[
42]
S. D. Robertson, R. E. Mulvey, Angew. Chem. Int. Ed, 2013, 52,
1
1470-11487.
[
[
43]
44]
M. P. Coles, Coord. Chem. Rev., 2015, 297-298, 2-39.
R. Neufeld, R. Michel, R. Herbst-Irmer, R. Schöne, D. Stalke, Chem.
Eur. J., 2016, 22, 12340-12346.
[
[
[
[
[
[
45]
46]
47]
48]
49]
50]
H. Görls, P. Schüler, M. Westerhausen, S. Krieck, Dalton Trans.,
2
019, 48, 8966-8975.
A. Jacobi von Wangelin, P. Ghosh, Org. Chem. Front., 2020, 7, 960-
66.
9
P. Schüler, B. E. Fener, N. Ueberschaar, P. Bellstedt, H. Görls, S.
Krieck, M. Westerhausen, Chem. Eur. J., 2020, In print.
P. Jutzi, A. H. Cowley, F. X. Kohl, J. G. Lasch, N. C. Norman, E.
Schluter, Angew. Chem. Int. Ed, 1984, 23, 616-617.
M. G. Davidson, D. M. Cousins, D. García-Vivó, M. F. Mahon,
Dalton Trans., 2010, 39, 8203-8209.
S. D. Bull, P. C. Andrews, M. Koutsaplis, New. J. Chem., 2010, 34,
1
678-1691.
[
[
[
51]
52]
53]
A. Stasch, C. P. Sindlinger, Dalton Trans., 2014, 43, 14334-14345.
F. H. Allen, Acta. Cryst., 2002, B58.
D. Stalke, T. Stey, in The Chemistry of Organolithium Compounds,
ed. I. M. Z. Rappoport, John Wiley & Sons, 2004, pp. 47-120.
P. v. R. Schleyer, C. Schade, Adv. Organomet. Chem., 1987, 27,
[
54]
1
69-278.
[
[
[
[
55]
56]
57]
58]
E. Weiss, Angew. Chem. Int. Ed, 1993, 32, 1501-1523.
W. Tornau, E. G. Hoffmann, Angew. Chem., 1961, 73, 578.
W. Tornau, E. G. Hoffmann, United States Pat., 1964. DE 1162369
F. Olbrich, H. Nekola, U. Behrens, Z. Anorg. Allg. Chem., 2002, 628,
2
067-2070.
[
[
[
[
[
[
59]
60]
61]
62]
63]
64]
R. Nassar, J. F. Allan, E. Specht, A. Beatty, N. Calin, K. W.
Henderson, J. Am. Chem. Soc., 2004, 126, 484-485.
R. N. R. Broomhall-Dillard, W. J. Evans, J. W. Ziller,
Organometallics, 1996, 15, 1351-1355.
W. Clegg, D. R. Armstrong, A. M. Drummond, S. T. Liddle, R. E.
Mulvey, J. Am. Chem. Soc., 2000, 122, 11117-11124.
A. El-Hamdan, W. Uhl, G. Geiseler, K. Harms, Z. Anorg. Allg.
Chem., 2004, 630, 821-828.
A. R. Kennedy, H. R. L. Barley, R. E. Mulvey, Acta. Cryst., 2005, 61,
3
46-347.
A. Company, S. Krackl, S. Enthaler, M. Driess, Chem. Cat. Chem.,
011, 3, 1186-1192.
2
6
This article is protected by copyright. All rights reserved.

European Journal of Inorganic Chemistry
10.1002/ejic.202000434
FULL PAPER
Entry for the Table of Contents
Key Topic: Alkali Metal Aluminates
Formally co-complexes between monomeric forms of (i-Bu)2Al(OBu-t) and t-BuO(AM), a series of lithium, sodium, and potassium
aluminates exhibit contacted ion pair structures, which irrespective of the alkali metal, share similar basic frameworks comprising
heterodinuclear [AlO(AM)O] ring cores with four-coordinate Al and four or five coordinate AM centres, the latter completed by
assorted donor ligands.
7
This article is protected by copyright. All rights reserved.