A new amidoimidomalonate zinc complex with a sedecameric solid state structure catalyzing the copolymerization of CO2 and cyclohexene oxide

Article abstract of DOI:10.1016/j.jorganchem.2006.04.018

A new amidoimidomalonate ligand was synthesized in a short and effective way and the zinc acetate complex thereof was prepared. XRD investigation revealed an unprecedented solid state structure, where the sedecameric complex [(lig)₂Zn₄

Full text of DOI:10.1016/j.jorganchem.2006.04.018

Journal of Organometallic Chemistry 691 (2006) 3397–3402
www.elsevier.com/locate/jorganchem
Note
A new amidoimidomalonate zinc complex with a sedecameric
solid state structure catalyzing the copolymerization of CO2
and cyclohexene oxide
*
*
Mario Kro¨ger , Cristina Folli, Olaf Walter, Manfred Do¨ring
Forschungszentrum Karlsruhe, Institute for Technical Chemistry (ITC-CPV) Hermann-von-Helmholtz-Platz 1,
D-76344 Eggenstein-Leopoldshafen, Germany
Received 14 December 2005; received in revised form 25 March 2006; accepted 18 April 2006
Available online 26 April 2006
Abstract
A new amidoimidomalonate ligand was synthesized in a short and effective way and the zinc acetate complex thereof was prepared.
XRD investigation revealed an unprecedented solid state structure, where the sedecameric complex [(lig)2Zn4(OAc)4]4 builds the edges of
a square cavity. Each edge is made up by a similar unit [(lig)2Zn4(OAc)4] with four zinc atoms. The complex is an active catalyst in the
copolymerization of CO2 and cyclohexene oxide and produces polyethercarbonates with broad molecular weight distributions.
ꢀ 2006 Elsevier B.V. All rights reserved.
Keywords: Carbon dioxide fixation; Copolymerization; Imidomalonates; Polycarbonates; Zinc complexes
1. Introduction
predominantly heterogeneous catalysts were developed,
leading to rather low activities [6]. Only over the last dec-
ade, new homogeneous catalysts with higher activities, like
zinc phenoxides [7] or chromium [8] and cobalt [9,10] salen
complexes were discovered. The rapidly growing interest in
the reaction has been thoroughly documented in several
recent reviews [11–13]. The most active catalysts known
to date are zinc complexes with b-diketiminate ligands
[14–16]. In homogeneous catalysis, such b-diketiminate
ligands play an important role as spectator ligands by
means of their strong binding to the metal, their tunable
steric demand and their diversity of binding modes [17].
With several metals, coordinately unsaturated complexes
are formed, which can catalyze a number of important
reactions like the oligomerization and polymerization of
olefins [18–20], the polymerization of methyl methacrylate
[21] or the polymerization of lactide [22,23]. Our group
has reported a zinc complex with new aminoimidoacrylate
ligands 1, which showed high catalytic activities in the
copolymerization of cyclohexene oxide and carbon dioxide
(Scheme 1) [24]. Based on this active catalyst as a lead
structure, we have developed a new ligand, the amidoimi-
The fixation of carbon dioxide as a C1 building block is
still one of the most prominent goals in green and synthetic
chemistry [1]. CO2 is widely abundant, it exhibits no toxic-
ity or flammability and it is inexpensive; thus it is a very
attractive synthon. The only major drawback is its low
reactivity, which can be overcome by catalytic activation
[2–4]. One of the most important and promising routes
towards the utilization of carbon dioxide is the copolymer-
ization with oxiranes to produce aliphatic polycarbonates.
Apart from the advantages of CO2 utilization, this reaction
combines several other features for high sustainability: A
perfectly atom efficient route to polycarbonates that needs
no other solvent and yields a biodegradable polymer. In the
first years after the discovery of the reaction by Inoue [5],
*
Corresponding authors. Present address: Freudenberg Forschungsdi-
enste KG, Elastomers, 69465 Weinheim, Germany. Tel.: +49 6201 80 7285
(M. Kro¨ger); Tel.: +49 7247 82 4385; fax: +49 7247 82 2244 (M. Do¨ring).
E-mail addresses: mario.kroeger@freudenberg.de (M. Kro¨ger),
manfred.doering@itc-cpv.fzk.de (M. Do¨ring).
0022-328X/$ - see front matter ꢀ 2006 Elsevier B.V. All rights reserved.
doi:10.1016/j.jorganchem.2006.04.018

3398
M. Kr€oger et al. / Journal of Organometallic Chemistry 691 (2006) 3397–3402
1 acts as an N,N-chelating ligand. In the solid state, the
resulting complex [(1)Zn(OAc)]2 has a dimeric structure,
where two tetrahedral zinc centers are bridged by two ace-
tate ions [24]. For the amidoimidomalonate 2, an N,N-che-
lated zinc complex was expected as well, because with
nickel, such complexes were made and showed to be active
as olefin oligomerization catalyst [27]. But, though in solu-
tion, the presence of monomeric and dimeric species is indi-
cated by the mass spectra, the solid state structure
contained much larger units. For the zinc acetate complex
with 2, an unprecedented solid state structure with the
overall formula [(2)2Zn4(OAc)4]4 was found. One unit is a
sedecamer, containing sixteen zinc atoms which build up
the edges of a square cavity (Fig. 1). Each side of this
square consists of identical [(2)2Zn4(OAc)4] units, which
are linked by acetate bridges. All four edges of the square
are occupied by the respective Zn3 atoms. The decisive
feature in the crystallographic independent unit [(2)2Zn4-
(OAc)4] is, that the carbonyl oxygen acts as a l-coordi-
nated donor to two zinc atoms (Fig. 2). Overall, both
ligands 2 are l3-g4-coordinating. All four zinc atoms are
N,O-connected to the ligands 2. Two zinc atoms (Zn1
and Zn3) form an N,O-chelate with a single ligand and
two zinc atoms (Zn2 and Zn4) bridge the two ligands 2.
With 98ꢁ, the bite angle of the N,O-chelates is slightly
wider than the 96ꢁ for the N,N-chelates in [(1)Zn(OAc)]2.
All zinc atoms have a distorted tetrahedral coordination
sphere. With their remaining two coordination sites, the
zinc atoms are interconnected via acetate bridges. While
the bridging zinc atoms (Zn2 and Zn4) are connected
within the [(2)2Zn4(OAc)4] unit (to each other and Zn1
and Zn3, respectively), the N,O-chelated zinc atoms (Zn1
and Zn3) have a connecting acetate bridge to a neighboring
unit. In both ligands 2, the backbone has a conjugated p-
electron system according to the mesomeric structures
shown in Scheme 3. The C–C and C–N bonds are nearly
of the same length and all bond lengths lie between the val-
ues for single and double bonds (Fig. 2).
O
O
O
O
O
cat.
O
C O
+
O
n
m
cat. = (lig)Zn(OAc) with lig = 1 or 2
R
Pri
O
O
R
iPr
iPr
N
R
N
1a iPr
NC
NH
iPr
1b Me
NH
O
Pri
Pri
1
2
Scheme 1. Copolymerization of cyclohexene oxide and carbon dioxide
catalyzed by zinc complexes with aminoimidoacrylate and amidoimido-
malonate ligands.
domalonate 2. Herein we describe the ligand and complex
synthesis, its catalytic activity and structure and compare it
to the catalysts with the aminoimidoacrylate ligands.
2. Results and discussion
Since the synthesis of suitable aminoimidoacrylate
ligands 1 needs three steps, alternative routes have been
sought. The amidoimidomalonate ligand 2 has a similar
structure, but can be synthesized in two steps (Scheme 2).
In the first step, an amidomalonate is prepared by reaction
of diethylmalonate with two equivalents of 2,6-diisopropyl-
aniline. This reaction requires no solvent, the emerging eth-
anol can be distilled off easily and the yield is very good
(90%). In the second step, one side of the symmetric malo-
namide is O-alkylated with the Meerwein salt triethyloxo-
nium tetrafluoroborate to generate the imido group [25].
The desired amidoimidomalonate is obtained in 64% yield,
corresponding to 58% overall yield for both steps.
A zinc acetate complex of the ligand was prepared ana-
log to the zinc acetate complexes of aminoimidoacrylates 1
and b-diiminates [24,26]. Treating the ligand with diethyl
zinc produces an ethylzinc complex as intermediate. After-
wards an equimolar amount of acetic acid is added to the
ethylzinc complex to give the acetate complex. As expected,
Like the zinc acetate complexes of 1, the described com-
plex of 2 is an active catalyst for the copolymerization of
carbon dioxide and cyclohexene oxide (Scheme 1). None-
theless, due to the different catalyst structures, the copoly-
merization results are substantially different, even though
the large complex structure 2 cannot be expected to remain
intact during homogeneous catalysis in solution. While
Pri
O
Pri
O
NH2
iPr
2
iPr
O
O
O
NH
NH
iPr
iPr
-
N
iPr
iPr
+ Et3O+BF4
+
O
160 °C
CH2Cl2, r.t.
NH
O
O
Pri
Pri
2
Scheme 2. Synthesis of the amidoimidomalonate ligand.

M. Kr€oger et al. / Journal of Organometallic Chemistry 691 (2006) 3397–3402
3399
Zn1B
Zn3B
Zn4B
Zn2B
Zn1B
Zn2B
Zn4B
Zn3A
Zn3B
Zn4A
Zn2
Zn2A
Zn1
Zn3
Zn1A
Zn4
Fig. 1. Overall structure of [(2)2Zn4(OAc)4]4. Phenyl residues and H-atoms are omitted for reasons of clarity.
EtO
HC
O
dipp
EtO
HC
O
dipp
EtO
HC
O
dipp
N
N
N
N
N
N
dipp
dipp
dipp
Scheme 3. Mesomeric structures of the deprotonated ligand 2.
(dipp = 2,6-diisopropylphenyl).
contains only about 40% carbonate linkages, so that it is
rather a polyethercarbonate, which comprises both, poly-
ether (m, see Scheme 1) and polycarbonate (n, Scheme 1)
sequences. The polycarbonate and polyether portions were
1
identified and quantiefied by their methine protons via H
Fig. 2. View to the crystallographic independent unit of the elementary cell
[(2)2Zn4(OAc)4] of [(2)2Zn4(OAc)4]4 drawn by ORTEP [28] with 25%
NMR spectroscopy in deuterated benzene (Fig. 3). Cyclic
polycarbonate, which can be a major side product, espe-
cially when propylene oxide is used as a monomer, was
found only in small traces in these copolymerizations with
cyclohexene oxide.
Secondly, the molecular weight distribution of the
resulting polymer is very broad (Mw/Mn > 10) and resem-
bles polydispersities that are produced by heterogeneous
catalysts. This can be explained by the exceptional struc-
ture of the catalyst, though the active catalytic species, dis-
solved in cyclohexene oxide, certainly differs distinctly from
the observed solid state structure. The catalyst contains at
˚
thermal ellipsoids. Selected atom distances (A) and angles (deg): Zn1–
N1 = 1.929(6), Zn1–O7 = 2.013(5), N1–C13 = 1.322(9), N2–C15 =
1.322(9), O7–C15 = 1.332(8), C13–C14 = 1.409(10), C14–C15 = 1.406(9),
Zn2–O7 = 1.999(4), Zn2–N4 = 1.949(6), Zn2–Zn4 = 2.9657(13), Zn4–O8
= 1.996(5), Zn4–N2 = 1.960(6), Zn3–O8 = 2.002(5), Zn3–N3 = 1.943(6),
N3–C42 = 1.306(9), N4–C44 = 1.337(9), O8–C44 = 1.328(8), C42–C43 =
1.401(10), C43–C44 = 1.388(10); N1–Zn1–O7 = 98.2(2), N3–Zn3–
O8 = 98.5(2).
[(1)Zn(OAc)]2 acts like a selective single site catalyst and
initiates a living polymerization, [(2)2Zn4(OAc)4]4 operates
less selective (Table 1). First of all, the resulting polymer

3400
M. Kr€oger et al. / Journal of Organometallic Chemistry 691 (2006) 3397–3402
Table 1
Performance of catalysts in the cyclohexene oxide/CO2 copolymerization
catalysta
t (h)
T (ꢁC)
p(CO2) (MPa)
TONb
TOFb (hꢀ1
)
gpolygꢀM1 ðhꢀ1
Þ
Carbonate linkages (%)c
Mn (kg mol-1)
Mw/Mn
d
[(1a)Zn(OAc)]2
[(1b)Zn(OAc)]2
[(2)2Zn4(OAc)4]4
[(2)2Zn4(OAc)4]4
a
2
2
2
2
100
100
100
90
4
4
4
4
270
396
108
46
135
198
51
293
430
235
101
58
75
40
34
12.6
15.8
4.9
1.72
1.21
19.99
13.75
23
3.0
A [CHO]:[Zn] ratio of 1000:1 was used throughout.
b
c
Mole of CHO consumed per mole of zinc (per hour for TOF).
Determined by 1H NMR.
d
Determined by GPC in THF.
50000
40000
30000
20000
10000
0
5.00
4.50
4.00
3.50
ppm (t1)
Fig. 3. 1H NMR spectrum (methine region) of polyethercarbonate (last entry in Table 1) in deuterated benzene.
least two different zinc centers with completely different
coordination spheres (Zn1 and Zn3 vs. Zn2 and Zn4, see
above). Consequently, this different zinc centers exhibit dif-
ferent catalytic activities and hence polymer chains with
different lengths are produced, leading to the observed
broad polydispersities. The tendency of the catalyst to pro-
duce more polyether and less carbonate linkages, especially
if compared to catalyst [(1a)Zn(OAc)]2, can possibly be
explained by the fact that the zinc atoms are N,O-coordi-
nated. Such zinc centers exhibit a higher Lewis acidity
and metal complexes with higher Lewis acidities, like alu-
minum triisopropoxide, are active catalyst for the ring
opening polymerization of oxygen containing ring systems
like epoxides or lactones [29]. Reactions of this type are
normally initiated by the electrophilic metal center attack-
ing the nucleophilic oxygen of the ring. Since CO2 is much
less reactive than the epoxide, a good catalyst for a per-
fectly alternating copolymerization should be a rather
bad catalyst for epoxide homopolymerization. Overall,
the catalytic activity of the presented system is good and
much higher than for the known heterogeneous catalytic
systems. The behaviour of [(2)2Zn4(OAc)4]4 seems to be
comparable to aluminum triisopropoxide, which forms
oligomeric solid state structures with different Al coordina-
tion spheres and exhibits similar catalytic activities and
selectivities [29]. The produced polyethercarbonates are
polymers with interesting material properties. For example,
they exhibit a high solubility in supercritical CO2 as was
shown by Beckman et al. [30].
3. Conclusion
In conclusion, we prepared a new amidoimidomalonate
ligand 2 and a zinc acetate complex thereof, which showed
an exceptional sedecameric solid state structure and inter-
esting catalytic activities in the copolymerization of carbon
dioxide and cyclohexene oxide leading to polyethercarbon-
ates with broad polydispersities.

M. Kr€oger et al. / Journal of Organometallic Chemistry 691 (2006) 3397–3402
3401
4. Experimental
4.50 (q, 2H, OCH2), 3.25 (s, 2H, CH2), 3.08 (m7, 2H,
CH), 2.87 (m7, 2H, CH), 1.47 (t, 3H, CH3), 1.21 (d, 12H,
CH3), 1.20 (d, 6H, CH3), 1.16 (d, 6H, CH3). 13C NMR
(CDCl3) d 165.4, 154.9, 146.2, 137.8, 131.0, 128.6, 123.8,
123.7, 123.6, 123.2, 62.6, 38.4, 28.8, 28.3, 23.4, 22.7, 14.5.
EI+-HR-MS: m/z 450.3246 (calcd.), found 450.3172 for
C29H42N2O2, d = 7.4 mDa; m.p. 158.2–159.9 ꢁC.
4.1. General considerations
NMR spectra were recorded on a Bruker spectrometer
with 250 MHz (1H) and 62.9 MHz (13C) at 293 K. Mass
spectra were obtained using electron ionisation (EI), elec-
tron spray ionisation (ESI) or field ionisation (FI). FI-
and EI-spectra were recorded with Micromass GCT and
Finnigan MAT GCQ spectrometers, ESI-spectra were
recorded with a Helwett-Packard 1100 MSD spectrometer.
Melting points were either determined by using capillaries
4.4. Preparation of [(2)2Zn4(OAc)4]4
The amidoimidomalonate 2 (2 g, 4.4 mmol) was dis-
solved in toluene (30 mL) and after cooling to 0 ꢁC, a dieth-
ylzinc solution (7 mL of a 1.1 M solution in toluene,
7.7 mol) was added. The solution was stirred at 75 ꢁC for
18 h, afterwards all volatiles were removed under vacuum.
The intermediate ethylzinc complex was dissolved in
dichloromethane (20 mL), cooled to 0 ꢁC and acetic acid
was added dropwise (264 mg, 4.4 mmol). The product crys-
tallized, when the concentrated solution was layered with
and an apparatus of Buchi, or with differential scanning
¨
calorimetry (DSC) with a Mettler Toledo DSC822e. IR
spectra were recorded with a Perkin Elmer System 2000
FT-IR. Molecular weights of the polymers were deter-
mined by Gel Permeation Chromatography (GPC) using
a Merck-Hitachi System (L-6200 intelligent pump, L-
7490 RI-detector ). A pre-column and two different GPC
1
˚
columns (PSS SDV 5 l 1000 and 100 A) were run with tet-
hexane. Yield: 1.37 g (2.3 mmol, 52%). H NMR (CDCl3)
rahydrofuran at 35 ꢁC at 1 mL/min and were calibrated by
d 7.21–6.82 (bm, 6H, HAryl), 3.49–3.03 (b, 6H, OCH2,
CH2, CH), 2.93 (m7, 2H, CH), 2.20 (bs, 3H, OC(O)CH3),
1.41–0.81 (d, 27H, CH3). 13C NMR (CDCl3) d 165.7,
155.7, 147.8, 146.6, 138.3, 133.0, 129.6, 128.2, 124.5,
123.8, 123.5, 123.1, 122.5, 62.6, 28.7, 28.2, 27.9, 27.5,
24.5, 23.6, 23.3, 23.1, 22.6, 14.0. ESI+-MS: m/z 573
([(2)Zn(OAc)]+ + 1), 1146 ð½ð2ÞZnðOAcÞꢁþ2 þ 2Þ.
polystyrene standards.
4.2. Preparation of N,N0-bis(2,6-diisopropylphenyl)-
malonamide
A mixture of diethyl malonate (10.10 g, 0.062 mol) and
2,6-diisopropylaniline (25.00 g, 0.127 mol) was heated at
160 ꢁC for 10 h, while the produced ethanol was distilled
out of the reaction mixture. The mixture was cooled to
r.t. and the resulting powder was mixed with 200 ml of cold
hexane and stirred for 1 h. The microcrystalline pale-pink
powder was filtered and washed with hexane. Yield:
4.5. General copolymerization procedure
An autoclave (Parr) was heated to 95 ꢁC under vacuum
for 16 h. [(2)2Zn4(OAc)4]4 (43 mg, 0.075 mmol Zn) and
cyclohexene oxide (7.34 g, 74.9 mmol) were brought into
the autoclave, which was then heated to reaction tempera-
ture and pressurized with CO2 (4 MPa). After 2 h the reac-
tor was cooled, vented and a small sample was taken for
analysis. The resulting polyethercarbonate was dissolved
in dichloromethane (5 mL), precipitated from MeOH
(20 mL), collected and dried under vacuum to constant
weight. Characterization of the polymers was done by IR
(polycarbonate CO band at 1749 cm1), NMR and GPC.
1H NMR (C6D6) d 4.9 (bs, CH, polycarbonate), 3.6 (bs,
CH, polyether), 2.2–1.1 (bm, CH2, cyclohexyl).
1
23.79 g (56 mmol, 90%). H NMR (CDCl3) d 8.48 (s, 2H,
NH), 7.20 (t, 1H, HAryl), 7.10 (d, 4H, HAryl), 3.62 (s, 2H,
CH2), 2.98 (m7, 4H, CH), 1.11 (d, 24H, CH3). 13C NMR
(CDCl3) d 167.1, 145.9, 130.7, 128.5, 123.5, 42.7, 28.9,
23.6. EI+-HR-MS: m/z 422.2933 (calcd), found 422.2910
for C27H38N2O2, d = 2.3 mDa; m.p. 270.3–271.7 ꢁC.
4.3. Preparation of ethyl-N-(2,6-diisopropylphenyl)-3-
[(2,6-diisopropylphenyl)amino]-3-oxopropanimidoate (2)
A mixture of N,N0-bis(2,6-diisopropylphenyl)malona-
mide (10.00 g, 24 mmol) and a 1.0 M solution of tri-
ethyloxonium tetrafluoroborate in dichloromethane
(74.08 g, 56 mmol) was stirred 20 d at ambient tempera-
ture. The solvent was evaporated in vacuum and the resi-
due was washed with 160 ml of abs. diethylether and
filtered. Then it was taken up in 60 ml of abs. diethylether,
cooled to 0 ꢁC and triethylamine (7.5 ml, 54 mmol) was
slowly added. The mixture was stirred at r.t. for 2 h and
then it was filtered. The ether phases were collected and
the solvent was removed under reduced pressure; a white
solid precipitated, which was recrystallized from tolu-
4.6. Crystal structure determination
The intensity data for the compounds were collected by
a Siemens Smart 1000 CCD diffractometer using graphite-
monochromated Mo Ka radiation. Data were corrected for
Lorentz and polarization effects, but not for absorption
[31,32].
The structures were resolved by direct methods (SHELXS
[33]) and refined by full-matrix least squares techniques
against F 2o (SHELXL-97 [34]). The hydrogen atoms were
localized by difference Fourier synthesis and refined iso-
tropically. All non-hydrogen atoms were refined anisotrop-
ically [34] (For further details see Table 2).
1
ene:hexane = 3:1. Yield: 6.97 g (15 mmol, 64%). H NMR
(CDCl3) d 7.59 (s, 1H, NH), 7.34–7.02 (m, 6H, HAryl),

3402
M. Kr€oger et al. / Journal of Organometallic Chemistry 691 (2006) 3397–3402
[2] W. Leitner, Coord. Chem. Rev. 153 (1996) 257.
Table 2
[3] A. Behr, Carbon Dioxide Activation by Metal Complexes, VCH,
Weinheim, 1998.
[4] D. Walther, M. Ruben, S. Rau, Coord. Chem. Rev. 182 (1999) 67.
[5] S. Inoue, H. Koinuma, T. Tsuruta, Makromol. Chem. 169 (1969)
210.
[6] W. Kuran, Prog. Polym. Sci. 23 (1998) 919.
[7] D.J. Darensbourg, M.W. Holtcamp, G.E. Struck, M.S. Zimmer,
S.A. Niezgoda, P. Rainey, J.B. Robertson, J.D. Draper, J.H.
Reibenspies, J. Am. Chem. Soc. 121 (1999) 107.
[8] D.J. Darensbourg, J.C. Yarbrough, J. Am. Chem. Soc. 124 (2002)
6335.
[9] Z.Q. Qin, C.M. Thomas, S. Lee, G.W. Coates, Angew. Chem., Int.
Ed. 42 (2003) 5484.
[10] X.-B. Lu, Y. Wang, Angew. Chem. 116 (2004) 3658.
[11] G.W. Coates, D.R. Moore, Angew. Chem., Int. Ed. 43 (2004) 6618.
[12] D.J. Darensbourg, R.M. Mackiewicz, A.M. Phelps, D.R. Billodeaux,
Acc. Chem. Res. 37 (2004) 836.
[13] H. Sugimoto, S. Inoue, J. Poly. Sci. A: Chemistry 42 (2004) 5561.
[14] M. Cheng, D.R. Moore, J.J. Reczek, B.M. Chamberlain, E.B.
Lobkovsky, G.W. Coates, J. Am. Chem. Soc. 123 (2001) 8738.
[15] D.R. Moore, M. Cheng, E.B. Lobkovsky, G.W. Coates, Angew.
Chem. 114 (2002) 2711.
[16] S.D. Allen, D.R. Moore, E.B. Lobkovsky, G.W. Coates, J. Am.
Chem. Soc. 124 (2002) 14284.
[17] L. Bourget-Merle, M.F. Lappert, J.R. Severn, Chem. Rev. 102 (2002)
3031.
[18] J. Feldman, S.J. McLain, A. Parhasarathy, W.J. Marshall, J.C.
Calabrese, S.D. Arthur, Organometallics 16 (1997) 1514.
[19] H.L. Wiencko, E. Kogut, T.H. Warren, Inorg. Chim. Acta 345 (2003)
199.
[20] M.S. Zhou, S.P. Huang, L.H. Weng, W.H. Sun, D.S. Liu, J.
Organomet. Chem. 665 (2003) 237.
Crystallographic data
[(2)2Zn4(OAc)4]4
Empirical formula
CCDC No.
C264H368N16O48Zn16 Æ 2.4CH2Cl2
283845
5783.48
200(2)
0.71073
Tetragonal
P42/n (no. 86)
fw (g Æ molꢀ1
)
Temperature (K)
˚
Wavelength k (A)
Crystal system
Space group
Unit cell dimensions
˚
a (A)
29.3528(19)
29.3528(19)
20.7093(19)
90
90
90
17843(2)
2
1.076
1.145
6058
0.25 · 0.1 · 0.3
1.70–28.28
ꢀ39 6 h 6 38,
ꢀ 38 6 k 6 38,
ꢀ26 6 l 6 27
160406
˚
b (A)
˚
c (A)
a (ꢁ)
b (ꢁ)
c (ꢁ)
3
˚
V (A )
Z
qcalcd (g Æ cmꢀ3
)
l (mmꢀ1
F(000)
)
Crystal size (mm3)
h Range for data collection (ꢁ)
Index ranges
Reflections collected
Reflections observed
Independent reflections [Rint
Data/restraints/parameters
Goodness-of-fit on F2
9215
]
22031 [0.1262]
22031/0/831
1.061
Final R indices [I > 2r(I)]
R indices (all data)
R1 = 0.0877, wR2 = 0.2771
R1 = 0.2070, wR2 = 0.3607
[21] A.P. Dove, V.C. Gibson, E.L. Marshall, A.J.P. White, D.J. Williams,
Chem. Commun. (2002) 1208.
[22] M. Cheng, A.B. Attygalle, E.B. Lobkovsky, G.W. Coates, J. Am.
Chem. Soc. 121 (1999) 11583.
[23] A.P. Dove, V.C. Gibson, E.L. Marshall, A.J.P. White, D.J. Williams,
Chem. Commun. (2001) 283.
[24] M. Kro¨ger, C. Folli, O. Walter, M. Do¨ring, Adv. Synth. Catal. 347
(2005) 1325.
[25] H. Ahlbrecht, C. Vonderheid, Chem. Ber. 106 (1973) 2009.
[26] S.D. Allen, D.R. Moore, E.B. Lobkovsky, G.W. Coates, J. Organo-
met. Chem. 683 (2003) 137.
[27] M.E. Bluhm, C. Folli, D. Pufky, M. Kro¨ger, O. Walter, M. Do¨ring,
Organometallics 24 (2005) 4139.
Crystallographic data for the structural analysis has
been deposited with the Cambridge Crystallographic Data
Centre, CCDC No. 283845. Copies of this information
may be obtained free of charge from: The Director, CCDC,
12, Union Road, Cambridge CB2 1EZ, UK; fax: (+44)
1223 336 033; or e-mail: deposit@ccdc.cam.ac.uk or
www: http://www.ccdc.cam.ac.uk.
[28] L.J. Farrugia, J. Appl. Crystallogr. 30 (1997) 565.
[29] T. Zevaco, J. Sypien, A. Jansen, E. Dinjus, Green Chem. 7 (2005)
659.
References
[30] T. Sarbu, T. Styranec, E.J. Beckman, Nature 405 (2000) 165.
[31] COLLECT, Data Collection Software, Nonius B.V., Netherlands, 1998.
[32] Z. Otwinowski, W. Minor, in: C.W. Carter, R.M. Sweet (Eds.),
Macromolecular Crystallography, Part A, vol. 276, Academic Press,
1997.
[33] G.M. Sheldrick, Acta Crystallogr. Sect. A 46 (1990) 467.
[34] G.M. Sheldrick, SHELXL-97, University of Go¨ttingen, Germany,
1993.
[1] H. Arakawa, M. Aresta, J.N. Armor, M.A. Barteau, E.J. Beckman,
A.T. Bell, J.E. Bercaw, C. Creutz, E. Dinjus, D.A. Dixon, K.
Domen, D.L. DuBois, J. Eckert, E. Fujita, D.H. Gibson, W.A.
Goddard, D.W. Goodman, J. Keller, G.J. Kubas, H.H. Kung, J.E.
Lyons, L.E. Manzer, T.J. Marks, K. Morokuma, K.M. Nicholas, R.
Periana, L. Que, J. Rostrup-Nielson, W.M.H. Sachtler, L.D.
Schmidt, A. Sen, G.A. Somorjai, P.C. Stair, B.R. Stults, W. Tumas,
Chem. Rev. 101 (2001) 953.