Bimetallic fluorine-substituted anilido-aldimine zinc complexes for CO 2/(cyclohexene oxide) copolymerization

Article abstract of DOI:10.1021/ic060060r

Regioselective nucleophilic aromatic substitution of an o-fluorine occurs to afford fluorine-substituted o-phenylene-bridged bis(anilido-aldimine) compounds o-C₆H₄{(C₆H₂R ₂)N=CH-C₆F₄-(H)N(C₆H ₃R′₂)}₂ when Li(H)N-C₆H ₃R′₂ (R′ = iPr, Et, Me) is reacted with o-C₆H₄{(C₆H₂R₂)N=CH- C₆F₅}₂ (R = iPr, Et, Me) in a nonpolar solvent such as diethyl ether or toluene. Successive additions of Me₂Zn and SO₂ gas to the bis(anilido-aldimine) compounds afford quantitatively dinuclear μ-methylsulfinato zinc complexes o-C₆H ₄{[(C₆H₂R₂)N=CH-C₆F ₄-N(C₆H₃R′₂)-κ2N,N] -Zn(μ-OS(O)Me)}₂ (R = iPr, R′ = iPr, 3a; R = iPr, R′ = Me, 3c; R = Et, R′ = ⁱPr, 3d; R = Et, R′ = Et, 3e; R = Et, R′ = Me, 3f; R = Me, R′ = iPr, 3g; R = Me, R′ = Et, 3h; R = Me, R′ = Me, 3i). The molecular structure of 3c was confirmed by X-ray crystallography. Fluorine-substituted complexes 3a-i show significantly higher TOF (turnover frequencies) than the unfluorinated analogues for CO ₂/(cyclohexene oxide) copolymerization. The TOF is highly sensitive to the substituents R and R′, and the highest TOF (2480 h^-1) is obtained with 3g (R = Me, R′ = iPr). Complex 3g is less sensitive to the residual protic impurities present in the monomers and shows activity at such a low catalyst concentration as [Zn]:[cyclohexene oxide] = 1:50 000, at which the unfluorinated analogue is completely inactive. By realizing the activity at such an extremely low [Zn]:[cyclohexene oxide] ratio, we achieve a high TON (turnover number) up to 10 100. High-molecular-weight polymers (M_n, 100 000-200 000) are obtained with a rather broad molecular-weight distribution (M_w/M_n, 1.3-2.5). The obtained polymers are not perfectly alternating, and variable carbonate linkages (65-85%) are observed depending on the N-aryl ortho substituents R and R′ and the polymerization conditions.

Full text of DOI:10.1021/ic060060r

Inorg. Chem. 2006, 45, 4228−4237
Bimetallic Fluorine-Substituted Anilido−Aldimine Zinc Complexes for
CO2/(Cyclohexene Oxide) Copolymerization
Taekki Bok, Hoseop Yun, and Bun Yeoul Lee*
Department of Molecular Science and Technology, Ajou UniVersity, Suwon 443-749, Korea
Received January 11, 2006
Regioselective nucleophilic aromatic substitution of an o-fluorine occurs to afford fluorine-substituted o-phenylene-
bridged bis(anilido aldimine) compounds o-C6H4 (C6H2R2)N CH C6F4 (H)N(C6H3R 2 2 when Li(H)N C6H3R 2 (R
iPr, Et, Me) is reacted with o-C6H4 (C6H2R2)N CH C6F5 (R iPr, Et, Me) in a nonpolar solvent such as
diethyl ether or toluene. Successive additions of Me2Zn and SO2 gas to the bis(anilido aldimine) compounds
afford quantitatively dinuclear -methylsulfinato zinc complexes o-C6H4 [(C6H2R2)N CH C6F4 N(C6H3R 2)- 2N,N]-
Zn( -OS(O)Me) (R iPr, R′ ) iPr, 3a; R iPr, R′ ) Me, 3c; R Et, R′ ) Et, 3e;
Et, R′ ) iPr, 3d; R
Et, R′ ) Me, 3f; R Me, R′ ) iPr, 3g; R Me, R′ ) Et, 3h; R Me, R′ ) Me, 3i). The molecular
structure of 3c was confirmed by X-ray crystallography. Fluorine-substituted complexes 3a i show significantly
higher TOF (turnover frequencies) than the unfluorinated analogues for CO2/(cyclohexene oxide) copolymerization.
The TOF is highly sensitive to the substituents R and R
, and the highest TOF (2480 h-1) is obtained with 3g (R
Me, R′ ) iPr). Complex 3g is less sensitive to the residual protic impurities present in the monomers and shows
activity at such a low catalyst concentration as [Zn]:[cyclohexene oxide] 1:50 000, at which the unfluorinated
analogue is completely inactive. By realizing the activity at such an extremely low [Zn]:[cyclohexene oxide] ratio,
we achieve a high TON (turnover number) up to 10 100. High-molecular-weight polymers (Mn, 100 000 200 000)
are obtained with a rather broad molecular-weight distribution (Mw/Mn, 1.3 2.5). The obtained polymers are not
perfectly alternating, and variable carbonate linkages (65 85%) are observed depending on the N-aryl ortho
substituents R and R and the polymerization conditions.
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Introduction
totally petroleum-derived polymers. Carbon dioxide by itself
cannot be transformed to a polymer, but its copolymerization
with epoxide was reported in 1969 by Inoue et al.2 The
copolymerization requires a metal-containing catalyst, and
in recent decades numerous catalytic systems have been
developed.3 Landmarks in recent developments are the
â-diketiminato-Zn system4 introduced by Coates and the
salen-based chromium5 and cobalt systems6 introduced by
Darensbourg and Coates. Even though the turnover number
(TON) and the turnover frequency (TOF) have been dramati-
cally improved by the advent of the two catalytic systems,
the TON and TOF should be further improved to reach
commercial viability.
Recently, chemistry utilizing CO2 as a feedstock has drawn
considerable attention because CO2 is abundant, inexpensive,
and nontoxic.1 Environmental and economical benefits would
be great if the polymers derived from CO2 could replace
* To whom correspondence should be addressed. E-mail: bunyeoul@
ajou.ac.kr.
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A. T.; Bercaw, J. E.; Creutz, C.; Dinjus, E.; Dixon, D. A.; Domen,
K.; Dubois, D. L.; Eckert, J.; Fujita, E.; Gibson, D. H.; Goddard, W.
A.; Goodman, D. W.; Keller, J.; Kubas, G. J.; Kung, H. H.; Lyons, J.
E.; Manzer, L. E.; Marks, T. J.; Morokuma, K.; Nicholas, K. M.;
Periana, R.; Que, L.; Rostrup-Nielson, J.; Sachtler, W. M. H.; Schmidt,
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4228 Inorganic Chemistry, Vol. 45, No. 10, 2006
10.1021/ic060060r CCC: $33.50
© 2006 American Chemical Society
Published on Web 04/13/2006

CO2/(Cyclohexene Oxide) Copolymerization
Chart 1
We recently reported bimetallic anilido-aldimine-based
zinc catalysts (see Chart 1, compound 2) with which the TON
and the molecular weight of the polymer could be signifi-
cantly improved.7 The advantage of the bimetallic system
over the mononuclear analogue results from the fact that two
metal centers are involved in the chain propagation reaction,
as shown below (Chart 1, compound 1).8 To achieve a high
TON, we need the catalyst to be active even at a condition
of very low catalyst concentration. The mononuclear com-
plex, which is highly active at a condition of [Zn]:[cyclo-
hexene oxide (CHO)] ) 1:1000, shows negligible activity
when the [Zn]:[CHO] ratio is reduced to 1:5600.7,9 Because
the bimetallic system is active even at such a low catalyst
concentration as [Zn]:[CHO] ) 1:16 800, the TON could
be increased up to 3000. When the [Zn]:[CHO] ratio is
further reduced to 1:22 500 to increase the TON, it does not
show any activity because of the catalyst decomposition by
the residual protic impurities (presumably water) in the
monomers. That is, the catalyst should be less sensitive to
the protic impurities in order to increase TON further above
3000.
be expected because the fluorinated system might be less
sensitive to the protic impurities. The sensitivity of the
anilido-aldimine Zn system to the protic impurities may
come from the basicity of the deprotonated anilido nitrogen
atom. By the presence of the electron-withdrawing group
on the anilido ring, the basicity must be reduced, possibly
relieving the sensitivity of the complex toward the protic
impurities. Fluorinated phenoxyzinc complexes have been
shown to resist hydrolysis.11
Results and Discussion
Synthesis and Characterization. The anilido-aldimine
ligand system was first prepared by Piers by a nucleophilic
attack of LiN(H)Ar on a Schiff’s base constructed from
2-fluorobenzaldehyde and aniline,12 and the ligand system
used for the construction of 2 was prepared by the same
strategy. We guessed that the nitrogen donor on the Schiff’s
base facilitated the nucleophilic displacement of the fluoride
by coordinating to the lithium ion on LiN(H)Ar. If the guess
is correct, it is well-expected that the LiN(H)Ar can
regioselectively displace an o-fluorine atom on a Schiff’s
base constructed from pentafluorobenzaldehyde (eq 1). As
expected, the desired ortho-attacked product is obtained as
a major product in 60% yield when the Schiff’s base is
reacted with 4 equiv of LiN(H)(2,6-iPr2C6H3) in THF for 3
days at room temperature (eq 1). The observation of 4 signals
and the splitting pattern for each signal (-82.7 (td), -68.1,
-58.3 (t), -54.6 (d) ppm in C6D6) in the 19F NMR spectrum
strongly support the ortho-attacked structure drawn in eq 1.
The 1H NMR and 13C spectra are also in agreement with the
structure.
In the Coates’ â-diketiminato-Zn system, the introduction
of electron-withdrawing substituent(s) in the ligand backbone
results in dramatic increases in the TOF.10 From the Coates’
report, it is well expected that the bimetallic fluorine-
substituted anilido-aldimine system (see Chart 1, compound
3) would give a higher TOF. An increase in TON can also
(5) (a) Darensbourg, D. J.; Phelps, A. L.; Gall, N. L.; Jia, L. Acc. Chem.
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43, 1831. (d) Darensbourg, D. J.; Mackiewicz, R. M.; Rodgers, J. L.;
Fang, C. C.; Billodeaux, D. R.; Reibenspies, J. H. Inorg. Chem. 2004,
43, 6024. (e) Darensbourg, D. J.; Mackiewicz, R. M.; Billodeaux, D.
R. Organometallics 2005, 24, 144. (f) Darensbourg, D. J.; Phelps, A.
L. Inorg. Chem. 2005, 44, 4622. (g) Darensbourg, D. J.; Mackiewicz,
R. M. J. Am. Chem. Soc. 2005, 127, 14026.
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Qin, Z.; Thomas, C. M.; Lee, S.; Coates, G. W. Angew. Chem., Int.
Ed. 2003, 42, 5484. (c) Paddock, R. L.; Nguyen, S. T. Macromolecules
2005, 38, 6251. (d) Cohen, C. T.; Chu, T.; Coates, G. W. J. Am. Chem.
Soc. 2005, 127, 10869.
(7) (a) Lee, B. Y.; Kwon, H. Y.; Lee, S. Y.; Na, S. J.; Han, S.-i.; Yun,
H.; Lee, H.; Park, Y.-W. J. Am. Chem. Soc. 2005, 127, 3031. (b) Xiao,
Y.; Wang, Z.; Ding, K. Macromolecules 2006, 39, 128. (c) Xiao, Y.;
Wang, Z.; Ding, K. Chem.sEur. J. 2005, 11, 3668.
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Chem. Soc. 2003, 125, 11911.
(10) Moore, D. R.; Cheng, M.; Lobkovsky, E. B.; Coates, G. W. Angew.
Chem., Int. Ed. 2002, 41, 2599.
(11) Darensbourg, D. J.; Wildeson, J. R.; Yarbrough, J. C.; Reibenspies,
J. H. J. Am. Chem. Soc. 2000, 122, 12487.
(9) van Meerendonk, W. J.; Duchateau, R.; Koning, C. E.; Gruter, G.-J.
M. Macromol. Rapid Commun. 2004, 25, 382.
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E.; Parvez, M. Organometallics 2003, 22, 1577.
Inorganic Chemistry, Vol. 45, No. 10, 2006 4229

Bok et al.
a
Scheme 1
Figure 1. 19F NMR spectrum of a methyl zinc complex of 5.
Chart 2
a Legend: (i) C6H3R′2NHLi; (ii) ZnMe2; (iii) SO2.
Schiff’s bases 4a-c are prepared in excellent yields by
conventional methods from the 4,4′′-diamino-o-terphenyl
derivatives bearing alkyl substituents at the 3, 5, 3′′, and 5′′
positions.7 In contrast with the success on the construction
of the mononuclear ligand system shown in eq 1, the
construction of the dinuclear ligand system (5 in Scheme 1)
is unsuccessful under the same conditions. However, when
less-polar diethyl ether was employed as a solvent instead
of THF, desired compounds 5 are obtained as major products.
In the case of 5d, 5g, and 5i, the product is deposited as a
solid during the reaction to block further attacks of the LiN-
(H)Ar; consequently, this gives satisfactory yields (50-67%),
but in the preparations of the other derivatives, yields are
rather low (30-40%). The yield can be significantly
improved by employing nonpolar toluene as a solvent (60-
80%). Four signals are observed as two triplets, a doublet,
and a broad singlet in the 19F NMR spectra. The splitting
pattern supports the ortho-attacked products, as shown in
signals, instead of one, are observed as singlets, two of which
show the same intensity. Four singlet signals with the same
intensity ratio as that observed for the Zn-OS(CH3) signals
are also observed for the C6R2H2 hydrogens at 6.6-6.9 ppm.
This observation of several sets of signals instead of one set
of signals in the 1H NMR spectra arises from the isomerism
due to the tetrahedral nature of the sulfur atom shown below.
We can expect formation of three isomers A, B, and C by
the direction of the two methyl groups attached on the sulfur
atoms. For isomer A, the two Zn-OS(CH3) methyls are
magnetically inequivalent and hence two methyl signals
should be observed in a 1:1 intensity ratio. The two hydro-
gens on a C6R2H2 ring also become inequivalent by the
situation of the methyls, and two signals should be observed
in a 1:1 ratio as well. For isomers B and C, the two Zn-
OS(CH3) methyls and the two hydrogens on a C6R2H2 ring
are, respectively, equivalent, and one singlet signal should
be observed for each hydrogen. Mostly three signals are
observed for the NdCH hydrogen at 8.12-8.46 ppm as sing-
lets; but in some cases, two signals are observed, presumably
due to the collapse of the two signals. From the intensity
values for the singlet signals of Zn-OS(CH3), C6R2H2, or
NdCH hydrogens, we can calculate the ratios of the three
isomers A:B:C or A:C:B (see Chart 2). For 3a and 3d-f,
the ratios are (0.41-0.43):(0.41-0.44):(0.12-0.18), but for
3g-4i, the ratios are (0.50-0.57):(0.25-0.39):(0.11-0.21).
Interestingly, only two isomers are observed in a 0.25:0.75
ratio for complex 3c, from which single crystals suitable for
X-ray crystallography can be obtained by the slow evapora-
tion of solvent from a diethyl ether solution.
1
Scheme 1. In the H NMR spectra, the N-H signals are
observed at 10.80-11.14 ppm (C6D6), slightly downfield
shifted from the chemical shifts observed for the unfluori-
nated compounds (10.50-10.80 ppm in C6D6).
The addition of Me2Zn to the ligands cleanly affords the
1
desired bimetallic Zn-CH3 complexes. In the H spectra,
the N-H signals disappear and new Zn-CH3 signals appear
at -0.61 to -0.85 ppm as singlets. The Zn-CH3 carbon
signals are observed at -17.4 to -16.9 ppm in the 13C NMR
spectra. In the 19F NMR spectra, four well-split signals are
observed (Figure 1). The splitting pattern is unambiguously
assignable to a 1,2-disubstituted tetrafluorobenzene on the
3
4
basis of coupling constants of JFF ) 22 and 16 Hz, JFF
)
5
6 and 8 Hz, and JFF ) 8 Hz, which are in agreement with
the tabulated coupling constants.13
The addition of SO2 gas to the methyl zinc complexes
1
results in disappearance of the Zn-CH3 signals in the H
NMR spectra.14 New signals are observed at 1.3-1.8 ppm
(C6D6), which can be assigned to Zn-OS(CH3), but four
X-ray Crystallographic Studies. The structure of 3c was
confirmed by X-ray crystallographic studies (Figure 2). The
structure is not deviated severely from that observed for the
unfluorinated analogue.7 By the presence of the fluorine
(13) Becker, E. D. High-Resolution NMR: Theory and Chemical Applica-
tion, 2nd ed.; Academic Press: London, 1980; p 101.
(14) Eberhardt, R.; Allmendinger, M.; Luinstra, G. A.; Rieger, B. Orga-
nometallics 2003, 22, 211.
4230 Inorganic Chemistry, Vol. 45, No. 10, 2006

CO2/(Cyclohexene Oxide) Copolymerization
Polymerization Studies. The newly prepared fluorine-
substituted bimetallic complexes 3 are tested as catalysts for
CO2/[cyclohexene oxide (CHO)] copolymerization at a
condition of [Zn]:[CHO] ) 1:5600, at which the unfluori-
nated complexes 2 were studied. As previously reported, the
mononuclear â-diketiminato zinc complex shows negligible
activity at such a low catalyst concentration (entry 10 in
Table 1), which can be attributed to dissociation of the active
associated dimeric species 1 from the less-active monomeric
species at the low catalyst concentration. The TOF can be
roughly estimated by reading the rate of CO2 pressure drop.
Because some fluorine-substituted complexes show signifi-
cantly rapid CO2 pressure drop compared with that of the
unfluorinated system 2, the standard reaction time is reduced
to 2 from 5 h. As shown in Table 1, the activity is highly
sensitive to the N-aryl ortho substituents. When both sub-
stituents on the imine moiety (R) and the anilido moiety (R′)
are too large (3a, R ) R′ ) iPr), the activity is very low
(TOF ) 130 h-1), presumably because of the steric conges-
tion at the reaction site. Interestingly, all complexes bearing
the small methyl substituents on the anilido moiety (3c, 3f,
and 3i) show low activity (entries 2, 5, and 8), whereas high
activities are obtained with the complexes bearing large
substitutes on the anilido moiety (R′ ) iPr, Et) and small
substituents on the imine moiety (R ) Me or Et) (3d, e, g,
and h). A similar activity dependency on the N-aryl ortho
substituents was also observed for both the unfluorinated
complexes 2 and the mononuclear â-diketiminato zinc
complexes.7,10 The highest TOF is obtained with 3g (R) Me,
R′ ) iPr), with which the maximum conversion attainable
in this bulk polymerization (30%) is observed when the
reaction is quenched in 2 h (TON, 1570; TOF, 785 h-1).
With the unfluorinated analogue of 3g, almost the same
conversion was achieved in 5 h (TON, 1560; TOF 312 h-1).
Figure 2. Thermal ellipsoid plot (30% probability level) of 3c. Hydrogen
atoms are omitted for clarity. Selected bond distances (Å) and angles
(deg): N(1)-Zn(1), 1.959(6); N(2)-Zn(1), 1.979(6); N(3)-Zn(2), 1.960-
(6); N(4)-Zn(2), 1.997(5); O(1)-Zn(1), 1.973(6); O(2)-Zn(1), 1.966(5);
O(3)-Zn(2), 1.951(5); O(4)-Zn(2), 1.962(6); N(2)-C(15), 1.307(8); N(4)-
C(46), 1.291(8); N(1)-C(9), 1.340(8); N(3)-C(48), 1.348(8); Zn(1)-Zn-
(2), 4.821; N(2)-N(4), 6.991; N(1)-N(3), 7.866; C(9)-N(1)-C(1),
121.9(6); C(9)-N(1)-Zn(1), 124.7(4); C(1)-N(1)-Zn(1), 112.5(4); N(1)-
Zn(1)-N(2), 96.3(2); N(3)-Zn(2)-N(4), 95.4(2); O(2)-Zn(1)-O(1),
102.2(2); O(3)-Zn(2)-O(4), 105.8(2); O(3)-S(1)-O(1), 108.7(3).
atoms, the N(anilido)-Zn distances are increased to 1.959-
(6) and 1.960(6) Å from those observed for the unfluorinated
analogue (1.938(4) and 1.938(4) Å, respectively). Some
electron density on the anilido nitrogen atom is surely
withdrawn by the fluorinated benzene ring, and hence the
coordinating ability of the nitrogen atom is reduced; this
consequently leads to an increase in the N-Zn distance.
Because of more electron donation from the nitrogen atom
to the fluorinated benzene ring, the N(1)-C(9) and N(3)-
C(48) distances (1.340(8) and 1.348(8) Å, respectively)
become shorter than those observed for the unfluorinated
analogue (1.358(6) and 1.360(5) Å, respectively). The anilido
N atoms (N(1) and N(3)) show trigonal structure (sum bond
angles around the N atom of 359.1 and 359.9°), but the C(1)
and the C(53) atoms are not situated on the C6F4 plane
(dihedral angles of C(14)-C(9)-N(1)-C(1) and C(47)-
C(48)-N(3)-C(53) are 21.3 and 30.6°, respectively). The
corresponding carbon atoms are situated almost on the C6H4
plane in case of the unfluorinated analogue (the correspond-
ing dihedral angles are 13.9 and 11.4°). The Zn-Zn
separation is 4.821 Å, which is slightly shorter than those
observed for the unfluorinated analogue (4.867 Å).
In this kind of polymerization, the molecular weight
increases by the increase in TON if the chain-transfer
reactions can be excluded. Actually, by increasing the TON
with bimetallic system 2, we were able to increase the
molecular weight (Mn) up to 284 000. The reported molecular
weights (Mn) of the polymers obtained by the mononuclear
â-diketiminato zinc complexes have not exceeded 50 000.
As expected, the high-molecular-weight polymers are ob-
tained when the TONs are high (entries 3, 4, 6, and 7). The
Table 1. CO2/(Cyclohexene Oxide) Copolymerization Resultsa
TONb
TOFc
% carbonated
Mn
Mw/Mn
e
e
entry
catalyst
1
2
3
4
5
6
7
8
9
3a
3c
3d
3e
3f
3g
3h
3i
260
320
1420
1080
550
1570
1200
490
1560
56
130
160
710
540
275
785
600
245
312
5.6
25
44
72
86
84
65
86
75
94
74
75 000
25 000
120 000
91 000
43 000
118 000
122 000
38 000
225 000
27 000
4.7
1.7
1.7
1.3
1.8
2.1
1.4
1.4
1.7
1.8
unfluorinated 3gf
[(bdi)Zn(µ-OS(O)Me)]2
g
10
a Polymerization conditions: neat CHO (8.0 mL, 79 mmol), [Zn]:[CHO] ) 1:5600, 80 °C, 14 bar CO2 (initial pressure), 2 h. b Turnover number in moles
of CHO consumed per mole of Zn. c Turnover frequency in moles of CHO consumed per mole of Zn per hour. d Estimated by 1H NMR spectroscopy.
e Determined by GPC, calibrated with polystyrene standard in CDCl3. f Data from ref 7. g Polymerization data of mononuclear complex bdi )
(C6H3Et2)NdC(Me)CHdC(Me)N(C6H3Et2); data from ref 7.
Inorganic Chemistry, Vol. 45, No. 10, 2006 4231

Bok et al.
Table 2. CO2/(Cyclohexene Oxide) Copolymerization Results in Reduced [Zn]:[CHO] Ratiosa
entry
catalyst
[Zn]:[CHO]
time
TON
TOF
% carbonate
Mn
Mw/Mn
1
2
3
4
5
3g
3g
3g
3g
3g
3g
3g
3g
1:5600
1:5600
2
1
3
4.5
6.7
3.3
4
1570
1170
4860
7760
10 100
9440
9930
1070
2980
3120
382
785
1170
1620
1720
1510
2860
2480
119
65 (80)g
75
69
118 000
147 000
179 000
214 000
118 000
245 000
221 000
136 000
284 000
3900
2.1
1.8
1.7
1.7
2.5
1.2
1.4
2.1
1.7
1.2
1.1
1:22 400
1:33 600
1:50 000
1:50 000
1:50 000
1:67 200
1:16 800
1:4275
70
72
6b
7b,c
8
79 (88)g
78
9
19
91
97
90
9
10
11
unfluorinated 3gd
15
18
0.17
200
173
2290
CrCl(tfpp)/DMAPe
[Zn(µ-OMe)(bdi)]2
f
1:1000
23 000
a Polymerization conditions: neat CHO (8.0 mL and 79 mmol for entries 1-2; 16 mL and 158 mmol for entries 3-6), 80 °C, 14 bar CO2 (initial
pressure). b Contact time between the catalyst and CHO was eliminated and more-efficient stirring was exerted. c Polymerization temperature ) 50 °C.
d Data from ref 7. e tfpp ) tetraperfluorphenylphorphyrin, DMAP ) 4-(dimethylamino)pyridine; data from ref 15. f bdi ) (C6H3Me2)NdC(Me)C(CN)dC(Me)N-
(C6H3iPr2); data from ref 10. g The values in the parenthesis are the carbonate linkages after the polyether was removed by precipitation of the polymer in
THF by the addition of petroleum ether.
number-average molecular weights (Mn) exceeding 100 000
are obtained with complexes 3d, g, and h. The molecular
weight distributions (Mw/Mn) are rather broad (1.3-2.1),
which indicates that there are some kind of chain-transfer
reactions. The presence of chain-transfer reactions is further
supported by the fact that the observed molecular weights
are lower than those calculated from the TONs.
Unfluorinated complexes 2 gave almost-alternating co-
polymers (the carbonate linkages, >90%) but fluorine-
substituted complexes 3 do not give such highly alternating
copolymers. The carbonated linkage, which can be calculated
from the 1H NMR spectra, varies by the N-aryl substituents.
With 3e (R ) R′ ) Et), 3f (R ) Et, R′ ) Me), and 3h (R
) Me, R′ ) Et), the carbonate linkages are high (84-86%),
but highly active complexes 3d (R ) Et, R′ ) iPr) and 3g
(R ) Me, R′) iPr) give polymers of moderate carbonate
linkage (72 and 65%, respectively).
To achieve high TON, we need the complex to be active
at a low [Zn]:[CHO] ratio. The polymerizations were carried
out with 3g at reduced [Zn]:[CHO] ratios (Table 2). The final
status of the polymer solution obtained with 3g in the
standard condition ([Zn]:[CHO] ) 1:5600 and time ) 2 h)
is so viscous (conversion, 28%) that we suspect the catalyst
might not work in the later stage of the polymerization time
because of diffusion problems. When the polymerization time
is cut to 1 h under the same condition, 20% conversion is
obtained, which corresponds to a slight decrease in TON
(1170) but a significant increase in TOF (1170 h-1; entry
2). When the [Zn]:[CHO] ratio is reduced four times to
1:22 400 from 1:5600 and the reaction time is increased to
3 h, the complex is still active, giving 22% conversion, which
corresponds to TON ) 4860 and TOF ) 1620 h-1 (entry
3). When the ratio is further reduced to 1:33 600 and 1:50 000
(2.0 mg of catalyst in a neat 16 mL of CHO), most of the
catalyst is still alive and almost the same TOF values are
obtained (entries 4 and 5). Because the reaction time is
increased to 4.5 and 6.7 h inversely to the [Zn]:[CHO] ratios,
the TONs are increased to 7760 and 10 100, respectively.
When the ratio is further decreased to 1:67 200, a dramatic
decrease in TOF is observed, surely due to the catalyst
decomposition by the residual protic impurities present in
the monomers (entry 8). The highest TON, 10 100, attained
by 3g corresponds to 20 kg of polymer/g of Zn; this number
is astonishing when considering the highest TONs reported
with the unfluorinated analogue and the mononuclear
â-diketiminato Zn complexes are, respectively, 3000 (6.5 kg
of polymer/g of Zn) and 651 (1.4 kg of polymer/g of Zn).7,14
As previously discussed, a high TON can be obtained only
when the catalyst is active at a low [Zn]:[CHO] ratio. The
mononuclear â-diketiminato Zn complexes cannot show
activity at low [Zn]:[CHO] by dissociation to the less-active
monomeric species. Most of polymerization studies have
been carried out at a condition of [Zn]:[CHO] ) 1:1000.
The unfluorinated analogue of 3g showed activity only at a
[Zn]:[CHO] ratio up to 1:16 800. When the ratio is decreased
further to 1:22 400, unfluorinated complex 2 shows negligible
activity due to catalyst decomposition. Reduced basicity of
the anilido nitrogen because of the presence of the electron-
withdrawing fluorine atoms might relieve the sensitivity
toward the protic impurities, consequently preventing catalyst
decomposition at such a low catalyst concentration as [Zn]:
[CHO] ) 1:50 000. The highest TON reported in this
polymerization up to now is 3120, which was realized with
the porphyrin chromium complex CrCl(tfpp) (tfpp ) tetrap-
erfluorphenylporphyrin) activated with DMAP (4-(dimethy-
lamino)pyridine).15 It was attained with a long reaction time
of 18 h (TOF ) 173 h-1), and a very low molecular-weight
polymer (Mn ) 3900) was obtained (entry 10).
A demerit of the fluorinated system compared with the
unfluorinated analogue is relatively low carbonate linkage
in the obtained polymer, and the percent carbonate linkages
is not improved significantly by reducing the [Zn]:[CHO]
ratio (∼70%). The low carbonate linkage is possibly ascribed
either to contacting the catalyst with CHO in the absence of
16
CO2 or to a diffusion problem of the CO2 gas caused by
inefficient stirring. The carbonate linkage is actually im-
proved from 72 to 79% by eliminating the contacting time
between the catalyst and CHO in the absence of CO2 and
exerting more-efficient stirring (entry 6). When the polym-
erization temperature is lowered, the CO2 concentration in
(15) Mang, S.; Cooper, A. I.; Colclough, M. E.; Chauhan, N.; Holmes, A.
B. Macromolecules 2000, 33, 303.
(16) Koning, C.; Wildeson, J.; Parton, R.; Plum, B.; Steeman, P.; Darens-
bourg, D. J. Polymer 2001, 42, 3995.
4232 Inorganic Chemistry, Vol. 45, No. 10, 2006

CO2/(Cyclohexene Oxide) Copolymerization
the solution increases and hence more carbonate linkage can
be expected; however, it is not improved by lowering the
polymerization temperature from 80 to 50 °C (entry 7). To
see whether the low carbonate linkage arises from contami-
nation of the polymer with polyether that can be generated
during the polymerization reaction by some other species,
we fractionated the polymer by dissolving it in THF and
precipitated it by adding petroleum ether. The polyether is
soluble in petroleum ether and hence it can be removed by
the procedure. After the fractionation, the carbonate linkage
is improved further from 79 to 88% (entry 6), which is close
to that observed for the polymer obtained by the unfluori-
nated complex (91%). It is guessed that some anionic species,
which is active for the ring-opening polymerization of CHO,
is generated by the complex decomposition. Actually, the
polymer obtained at extremely a low [Zn]:[CHO] ratio, where
most of catalyst is decomposed, shows very low carbonate
linkage (19%, entry 8).
not perfectly alternating, and variable carbonate linkages
(65-85%) are observed depending on the N-aryl ortho
substituents, R and R′, and the polymerization conditions.
Experimental Section
General Remarks. All manipulations were performed under an
inert atmosphere using standard glovebox and Schlenk techniques.
Toluene, diethyl ether, and C6D6 were distilled from benzophenone
ketyl. The CO2 gas (99.99%) was purified by storing it overnight
in a bomb-reactor (500 mL) containing P2O5 at 17 bar pressure.
Cyclohexene oxide (CHO) was purified by stirring over KH for
several days and it was transferred under vacuum to a reservoir.
1H NMR (400 MHz), 13C NMR (100 MHz), and 19F NMR (376
MHz) spectra were recorded on a Varian Mercury plus 400. 19F
NMR spectra were calibrated and reported downfield from external
R,R,R-trifluorotoluene. Elemental analyses were carried out at the
Inter-University Center Natural Science Facilities, Seoul National
University. Gel permeation chromatograms (GPC) were obtained
at room temperature in CDCl3 using Waters Millennium.
By exerting more efficient stirring, we increased the TOF
almost doubly, and the highest TOF obtained by 3g is 2860
h-1 (entry 6), which corresponds to one CHO consumption
in every 1.3 s. The TOF is 9 times higher than that obtained
by the unfluorinated complex (312 h-1). The TOF is also
higher than that obtained by the highly efficient mononuclear
â-diketiminato Zn complexes {[(C6H3Me2)NdC(Me)C(CN)d
C(Me)N(C6H3iPr2)]Zn(µ-OMe)}2 (2290 h-1, entry 11).
The molecular weight (Mn) increases from 147 000 to
179 000 and finally 214 000 by an increase in the TON from
1170 to 4870 and 7760, respectively (entries 2-4), but the
molecular weight is decreased to 118 000 by the further
increase in the TON to 10 100. This unexpected decrease in
the molecular weight indicates that some chain-transfer
reactions occur by reducing the [Zn]:[CHO] ratio severely.17
Compound 4a. o-C6H4(C6H2iPr2-NH2)2 (1.50 g, 3.50 mmol),
pentafluorobenzaldehyde (2.74 g, 14.0 mmol), molecular sieves (4
Å, 500 mg), and toluene (30 mL) were added to a flask. After the
solution was refluxed overnight with a Dean-Stark apparatus, it
was filtered to remove the molecular sieves. The solvent was
removed by a rotary evaporator, and the residue was triturated with
hexane to give a yellow solid (2.69 g, 98%). Mp ) 207 °C. IR
1
(NaCl): 1634 (CdN) cm-1. H NMR (C6D6): δ 1.18 (d, J ) 7.2
Hz, 12H, CH3), 3.13 (septet, J ) 7.2 Hz, 2H, CH), 7.14 (s, 2H,
C6H2), 7.34 (AA′BB′, 1H, C6H4), 7.63 (AA′BB′, 1H, C6H4), 8.11
(s, 1H, NdCH). 13C{1H} NMR (C6D6): δ 23.88, 28.57, 111.3 (m),
125.66, 130.46, 136.88, 137.8 (dm, 2JCF ) 260 Hz), 139.10, 141.93,
2
2
142.3 (dm, JCF ) 260 Hz), 145.0 (dm, JCF ) 250 Hz), 147.95,
150.93. 19F{1H} NMR (C6D6): δ -69.21 (td, JFF ) 21 Hz, JFF
) 7.4 Hz, meta), -58.29 (t, 3JFF ) 21 Hz, para), -50.64 (dm, 3JFF
) 21 Hz, ortho). Anal. Calcd. for (C44H38F10N2): C, 67.34; H, 4.88;
N, 3.57. Found: C, 67.60; H, 4.67; N, 3.34.
3
4
Summary. Li(H)N-C6H3R′2 (R′ ) iPr, Et, Me) regio-
selectively attacks, in nonpolar solvent such as diethyl ether
or toluene, an o-fluorine atom on the Schiff’s base con-
structed from pentafluorobenzaldehyde, o-C6H4{(C6H2R2)Nd
CH-C6F5}2 (R ) iPr, Et, Me), to afford fluorine-substituted
o-phenylene-bridged bis(anilido-aldimine) compounds o-C6H4-
{(C6H2R2)NdCH-C6F4-(H)N(C6H3R′2)}2, from which
dinuclear µ-methylsulfinato zinc complexes o-C6H4-
{[(C6H2R2)NdCH-C6F4-N(C6H3R′2)-κ2N,N]Zn(µ-OS(O)-
Me)}2 (3a-i) are prepared quantitatively by the successive
addition of Me2Zn and SO2 gas. The structure of a complex
is confirmed by the X-ray crystallographic studies. Com-
plexes 3 show higher TOF (turnover frequency) for CO2/
(cyclohexene oxide) copolymerization than the unfluorinated
analogues. The activity is very sensitive to substituents R
and R′, and the highest TOF (2860 h-1) is obtained with the
complex of R ) Me and R′ ) iPr (3g). Complex 3g shows
activity at such a low catalyst concentration as [Zn]:
[cyclohexene oxide] ) 1:50 000 that a TON up to 10 100 is
attained. High-molecular-weight polymers (Mn, 100 000-
200 000) are obtained with rather broad molecular-weight
distributions (Mw/Mn, 1.3-2.5). The obtained polymers are
Compound 4b. The compound was synthesized by the same
conditions and procedures as those used for 4a using o-C6H4(C6H2-
Et2-NH2)2. A yellow solid was obtained in 92% yield. Mp ) 207
1
°C. IR (NaCl): 1643 (CdN) cm-1. H NMR (C6D6): δ 1.13 (t, J
) 7.6 Hz, 6H, CH3), 2.50 (q, J ) 7.6 Hz, 4H, CH2), 7.07 (s, 2H,
C6H2), 7.35 (AA′BB′, 1H, C6H4), 7.60 (AA′BB′, 1H, C6H4), 8.01
(s, 1H, NdCH). 13C{1H} NMR (C6D6): δ 15.36, 25.32, 111.2 (m),
128.86, 130.68, 132.50, 137.7 (dm, 2JCF ) 250 Hz), 138.93, 141.28,
2
2
142.2 (dm, JCF ) 250 Hz), 145.9 (dm, JCF ) 260 Hz), 149.04,
150.92. 19F{1H} NMR (C6D6): δ -69.36 (td, JFF ) 21 Hz, JFF
) 6.7 Hz, meta), -58.46 (t, 3JFF ) 21 Hz, para), -50.62 (dm, 3JFF
) 21 Hz, ortho). Anal. Calcd. for (C40H30F10N2): C, 65.93; H, 4.15;
N, 3.84. Found: C, 65.60; H, 4.37; N, 3.54.
3
4
Compound 4c. The compound was synthesized by the same
conditions and procedures as those used for 4a using o-C6H4(C6H2-
Me2-NH2)2. A yellow solid was obtained in 94% yield. Mp )
1
202 °C. IR (NaCl): 1634 (CdN) cm-1. H NMR (C6D6): δ 2.07
(s, 6H, CH3), 7.14 (s, 2H, C6H2), 7.34 (AA′BB′, 1H, C6H4), 7.55
(AA′BB′, 1H, C6H4), 7.74 (s, 1H, NdCH). 13C{1H} NMR (C6D6):
2
δ 18.63, 111.2 (m), 126.41, 130.31, 131.26, 137.6 (dm, JCF
)
2
260 Hz), 138.92, 140.87, 142.1 (dm, JCF ) 250 Hz), 145.9 (dm,
2JCF ) 260 Hz), 149.88, 151.15. 19F{1H} NMR (C6D6): δ -69.59
(td, 3JFF ) 20 Hz, 4JFF ) 7.1 Hz, meta), -58.68 (t, 3JFF ) 20 Hz,
3
para), -50.24 (dm, JFF ) 20 Hz, ortho). Anal. Calcd. for
(C36H22F10N2): C, 64.29; H, 3.30; N, 4.17. Found: C, 64.38; H,
(17) van Meerendonk, W. J.; Duchateau, R.; Koning, C. E.; Gruter, G.-J.
M. Macromolecules 2005, 38, 7306.
3.22; N, 4.34.
Inorganic Chemistry, Vol. 45, No. 10, 2006 4233

Bok et al.
Compound 5a. Compound 4a (0.282 g, 0.360 mmol), 2,6-
iPr2C6H3N(Li)H (0.460 g, 1.80 mmol), and toluene (4 mL) were
added to a vial inside a glovebox. The resulting slurry was stirred
for 2 days. After a saturated aqueous NaHCO3 solution (20 mL)
was added, the organic compound was extracted with ethyl acetate
(20 mL × 3). After the organic phase was dried with anhydrous
MgSO4, the solvent was removed by a rotary evaporator to give
an oily residue, which was purified by column chromatography on
silica gel eluting with hexane and toluene (v/v, 30:1). A yellow
solid was obtained in 62% yield (0.225 g). Mp ) 230 °C. IR
(NaCl): 3158 (N-H), 1656 (CdN) cm-1. 1H NMR (C6D6): δ 1.05
(d, J ) 7.2 Hz, 12H, CH3), 1.14 (d, J ) 7.2 Hz, 6H, CH3), 1.23 (d,
J ) 7.2 Hz, 6H, CH3), 3.04 (septet, J ) 7.2 Hz, 2H, CH), 3.35
(septet, J ) 7.2 Hz, 2H, CH), 7.05 (s, 2H, C6H2), 7.09 (d, J ) 7.6
Hz, 2H, C6H3), 7.20 (t, J ) 7.6 Hz, 1H, C6H3), 7.34 (AA′BB′, 1H,
C6H4), 7.61 (AA′BB′, 1H, C6H4), 8.58 (s, 1H, NdCH), 11.14 (s,
1H, NH). 13C{1H} NMR (C6D6): δ 23.26, 24.00, 24.90, 28.62,
29.47, 102.2 (m), 123.58, 125.75, 127.88, 128.15, 130.35, 131.0
(dm, 2JCF ) 240 Hz), 135.50, 136.41, 136.9 (dm, 2JCF ) 260 Hz),
137.97, 139.23, 141.83, 144.3 (dm, 2JCF ) 260 Hz), 146.26, 146.54,
Hz, 6H, CH3), 1.12 (d, J ) 7.2 Hz, 6H, CH3), 1.22 (d, J ) 7.2 Hz,
6H, CH3), 2.41 (q, J ) 7.6 Hz, 4H, CH2), 3.33 (septet, J ) 7.2 Hz,
2H, CH), 7.02 (s, 2H, C6H2), 7.09 (d, J ) 7.6 Hz, 2H, C6H3), 7.21
(t, J ) 7.6 Hz, 1H, C6H3), 7.34 (AA′BB′, 1H, C6H4), 7.59 (AA′BB′,
1H, C6H4), 8.51 (s, 1H, NdCH), 11.10 (s, 1H, NH). 13C{1H} NMR
(C6D6): δ 15.36, 23.45, 24.81, 25.28, 29.41, 102.3 (m), 123.62,
127.83, 128.12, 128.85, 130.65, 131.0 (dm, 2JCF ) 240 Hz), 133.51,
2
136.47, 136.8 (dm, JCF ) 240 Hz), 139.10, 141.20, 144.3 (dm,
2JCF ) 250 Hz), 146.30, 147.86, 148.7 (dm, 2JCF ) 250 Hz), 158.04.
3
4
19F{1H} NMR (C6D6): δ -82.46 (td, JFF ) 22 Hz, JFF ) 7.4
3
3
Hz), -67.75 (m), -58.03 (ddd, JFF ) 21 Hz), -55.34 (ddd, JFF
) 18 Hz). Anal. Calcd. for (C64H66F8N4): C, 73.68; H, 6.38; N,
5.37. Found: C, 73.60; H, 6.50; N, 5.24.
Compound 5e. The compound was synthesized by the same
conditions and procedures as those used for 5a using 4b and 2,6-
Et2C6H3N(Li)H. A yellow solid was obtained in 54% yield. Mp )
1
214-215 °C. IR (NaCl): 3158 (N-H), 1652 (CdN) cm-1. H
NMR (C6D6): δ 0.97 (t, J ) 7.6 Hz, 6H, CH3), 1.12 (t, J ) 7.6
Hz, 6H, CH3), 2.38 (q, J ) 7.6 Hz, 4H, CH2), 2.52-2.70 (m, 4H,
CH2), 6.99 (s, 2H, C6H2), 7.01 (d, J ) 7.6 Hz, 2H, C6H3), 7.11 (t,
J ) 7.6 Hz, 1H, C6H3), 7.34 (AA′BB′, 1H, C6H4), 7.57 (AA′BB′,
1H, C6H4), 8.50 (s, 1H, NdCH), 11.06 (s, 1H, NH). 13C{1H} NMR
(C6D6): δ 15.29, 15.43, 25.33, 25.68, 102.4 (m), 126.60, 127.51,
128.88, 130.58, 131.0 (dm, 2JCF ) 250 Hz), 133.49, 135.92, 136.7
2
148.7 (dm, JCF ) 240 Hz), 158.03. 19F{1H} NMR (C6D6): δ
3
3
-82.36 (br t, JFF ) 18 Hz), -67.92 (s), -57.89 (br t, JFF ) 18
3
Hz), -55.72 (br d, JFF ) 17 Hz). Anal. Calcd. for (C68H74F8N4):
C, 74.29; H, 6.78; N, 5.10. Found: C, 74.50; H, 6.47; N, 5.26.
Compound 5b. The compound was synthesized by the same
conditions and procedures as those used for 5a using 4a and 2,6-
Et2C6H3N(Li)H. A yellow solid was obtained in 82% yield. Mp )
2
(dm, JCF ) 240 Hz), 137.08, 139.07, 141.24, 141.58, 144.1 (dm,
2
2JCF ) 250 Hz), 147.84, 148.7 (dm, JCF ) 240 Hz), 157.97. 19F-
3
4
{1H} NMR (C6D6): δ -82.29 (td, JFF ) 22 Hz, JFF ) 6.3 Hz),
1
3
3
212 °C. IR (NaCl): 3157 (N-H), 1656 (CdN) cm-1. H NMR
-67.53 (m), -58.00 (t, JFF ) 20 Hz), -55.50 (dm, JFF ) 19
Hz). Anal. Calcd. for (C60H58F8N4): C, 73.00; H, 5.92; N, 5.68.
Found: C, 73.28; H, 5.73; N, 5.43.
(C6D6): δ 1.03 (d, J ) 7.2 Hz, 12H, CH3), 1.14 (t, J ) 7.2 Hz,
6H, CH3), 2.58 (dq, J ) 21 and 7.2 Hz, 2H, CH2), 2.68 (dq, J )
21 and 7.2 Hz, 2H, CH2), 3.02 (septet, J ) 7.2 Hz, 2H, CH), 7.02
(d, J ) 7.2 Hz, 2H, C6H3), 7.03 (s, 2H, C6H2), 7.10 (t, J ) 7.2 Hz,
1H, C6H3), 7.34 (AA′BB′, 1H, C6H4), 7.59 (AA′BB′, 1H, C6H4),
8.56 (s, 1H, NdCH), 11.13 (s, 1H, NH). 13C{1H} NMR (C6D6): δ
15.39, 23.96, 25.80, 28.64, 102.5 (m), 125.75, 126.70, 127.56,
Compound 5f. The compound was synthesized by the same
conditions and procedures as those used for 5a using 4b and 2,6-
Me2C6H3N(Li)H. A yellow solid was obtained in 63% yield. Mp
1
) 215-216 °C. IR (NaCl): 3153 (N-H), 1652 (CdN) cm-1. H
NMR (C6D6): δ 0.96 (t, J ) 7.6 Hz, 6H, CH3), 2.16 (s, 6H, CH3),
2.35 (q, J ) 7.6 Hz, 4H, CH2), 6.92-6.98 (m, 3H, C6H3), 6.99 (s,
2H, C6H2), 7.34 (AA′BB′, 1H, C6H4), 7.57 (AA′BB′, 1H, C6H4),
8.47 (s, 1H, NdCH), 10.99 (s, 1H, NH). 13C{1H} NMR (C6D6): δ
15.35, 18.71, 25.44, 102.8 (m), 126.85, 128.89, 130.60, 131.1 (dm,
2JCF ) 250 Hz), 133.41, 135.42, 136.6 (dm, 2JCF ) 250 Hz), 138.40,
2
127.85, 130.34, 131.1 (dm, JCF ) 240 Hz), 135.87, 136.6 (dm,
2JCF ) 250 Hz), 137.00, 137.93, 139.26, 141.62, 141.64, 141.89,
2
2
144.2 (dm, JCF ) 250 Hz),146.51, 148.7 (dm, JCF ) 250 Hz),
157.84. 19F{1H} NMR (C6D6): δ -82.27 (td, JFF ) 22 Hz, JFF
3
3
3
) 6.7 Hz), -67.59 (m), -57.92 (t, JFF ) 19 Hz), -55.85 (dm,
3JFF ) 20 Hz). Anal. Calcd. for (C64H66F8N4): C, 73.68; H, 6.38;
N, 5.37. Found: C, 73.53; H, 6.53; N, 5.45.
2
139.10, 141.25, 144.2 (dm, JCF ) 250 Hz), 147.79, 148.7 (dm,
2JCF ) 250 Hz), 157.64. 19F{1H} NMR (C6D6): δ -82.16 (td, 3JFF
4
3
Compound 5c. The compound was synthesized by the same
conditions and procedures as those used for 5a using 4a and 2,6-
Me2C6H3N(Li)H. A yellow solid was obtained in 75% yield. Mp
) 225 °C. IR (NaCl): 3158 (N-H), 1652 (CdN) cm-1. 1H NMR
(C6D6): δ 1.02 (d, J ) 7.2 Hz, 12H, CH3), 2.20 (s, 6H, CH3), 2.99
(septet, J ) 7.2 Hz, 2H, CH), 6.80-7.00 (m, 3H, C6H3), 7.02 (s,
2H, C6H2), 7.34 (AA′BB′, 1H, C6H4), 7.60 (AA′BB′, 1H, C6H4),
8.55 (s, 1H, NdCH), 11.13 (s, 1H, NH). 13C{1H} NMR (C6D6): δ
18.68, 23.73, 28.69, 102.7 (m), 125.71, 126.85, 127.85, 128.24,
) 22 Hz, JFF ) 6.3 Hz), -68.45 (m), -58.16 (t, JFF ) 21 Hz),
-55.58 (dm, 3JFF ) 20 Hz). Anal. Calcd. (C56H50F8N4): C, 72.24;
H, 5.41; N, 6.02. Found: C, 72.40; H, 5.37; N, 6.34.
Compound 5g. The compound was synthesized by conditions
and procedures similar to those used for 5a using 4c and
2,6-iPr2C6H3N(Li)H. Diethyl ether was used as a solvent. A yellow
solid was obtained in 67% yield. Mp ) 213-214 °C. IR (NaCl):
3162 (N-H), 1656 (CdN) cm-1. 1H NMR (C6D6): δ 1.07 (d, J )
7.2 Hz, 6H, CH3), 1.19 (d, J ) 7.2 Hz, 6H, CH3), 1.95 (s, 6H,
CH3), 3.28 (septet, J ) 7.2 Hz, 2H, CH), 7.08 (d, J ) 7.6 Hz, 2H,
C6H3), 7.16 (s, 2H, C6H2), 7.21 (t, J ) 7.6 Hz, 1H, C6H3), 7.31
(AA′BB′, 1H, C6H4), 7.53 (AA′BB′, 1H, C6H4), 8.28 (s, 1H, Nd
CH), 11.10 (s, 1H, NH). 13C{1H} NMR (C6D6): δ 18.70, 23.32,
24.75, 29.39, 102.3 (m), 123.60, 127.42, 130.35, 130.9 (dm,
2
130.27, 131.2 (dm, JCF ) 240 Hz), 135.22, 135.25, 136.5 (dm,
2JCF ) 240 Hz), 137.59, 137.65, 138.30, 139.17, 141.89, 144.0 (dm,
2
2JCF ) 250 Hz), 146.41, 148.7 (dm, JCF ) 240 Hz), 157.62. 19F-
3
3
{1H} NMR (C6D6): δ -82.50 (td, JFF ) 22 Hz, JFF ) 6.3 Hz),
3
3
-68.33 (m), -58.02 (t, JFF ) 23 Hz), -55.80 (dm, JFF ) 19
Hz). Anal. Calcd. for (C60H58F8N4): C, 73.00; H, 5.92; N, 5.68.
Found: C, 73.32; H, 5.73; N, 5.46.
2
2JCF ) 240 Hz), 131.23, 135.77, 136.2 (dm, JCF ) 250 Hz),
136.42, 138.99, 140.75, 144.5 (dm, 2JCF ) 250 Hz), 146.28, 148.7
2
Compound 5d. The compound was synthesized by conditions
and procedures similar to those used for 5a using 4b and
2,6-iPr2C6H3N(Li)H. Diethyl ether was used as a solvent. A yellow
solid was obtained in 47% yield. Mp ) 216 °C. IR (NaCl): 3162
(dm, JCF ) 250 Hz), 148.77, 158.05. 19F{1H} NMR (C6D6): δ
-82.73 (td, 3JFF ) 22 Hz, 4JFF ) 6.7 Hz), -68.01 (m), -58.23 (t,
3
3JFF ) 20 Hz), -54.75 (dm, JFF ) 18 Hz). Anal. Calcd. for
(C60H58F8N4): C, 73.00; H, 5.92; N, 5.68. Found: C, 73.24; H,
5.72; N, 5.40.
1
(N-H), 1656 (CdN) cm-1. H NMR (C6D6): δ 0.99 (t, J ) 7.6
4234 Inorganic Chemistry, Vol. 45, No. 10, 2006

CO2/(Cyclohexene Oxide) Copolymerization
Compound 5h. The compound was synthesized by the same
conditions and procedures as those used for 5a using 4c and 2,6-
Et2C6H3N(Li)H. A yellow solid was obtained in 67% yield. It was
obtained in 35% yield when diethyl ether was used as a solvent.
in a 0.43:0.43:0.14 ratio. Unambiguous signals for A, B (or C),
and C (or B) isomers are marked in bold, italic, and underlined,
respectively. 1H NMR (C6D6): δ 0.98-1.38 (m, 24H, CH3), 1.38,
1.54, 1.70, and 1.90 (s, 3H, SCH3), 2.21-2.60 and 3.20-3.55 (m,
4H, CH), 6.76, 6.82, 6.83, and 6.86 (s, 2H, C6H2), 6.98-7.14 (m,
3H, C6H3), 7.32 (AA′BB′, 1H, C6H4), 7.53 (AA′BB′, 1H, C6H4),
8.16, 8.27, and 8.23 (s, 1H, NdCH).
1
Mp ) 199 °C. IR (NaCl): 3158 (N-H), 1656 (CdN) cm-1. H
NMR (C6D6): δ 1.07 (t, J ) 7.6 Hz, 6H, CH3), 1.93 (s, 6H, CH3),
2.46-2.62 (m, 4H, CH2), 7.00 (d, J ) 7.6 Hz, 2H, C6H3), 7.07 (s,
2H, C6H2), 7.12 (t, J ) 7.6 Hz, 1H, C6H3), 7.32 (AA′BB′, 1H,
C6H4), 7.52 (AA′BB′, 1H, C6H4), 8.28 (s, 1H, NdCH), 10.95 (s,
1H, NH). 13C{1H} NMR (C6D6): δ 15.26, 18.76, 25.71, 102.4 (m),
126.60, 127.45, 130.31, 131.9 (dm, 2JCF ) 240 Hz), 135.85, 136.6
Compound 3b. The compound was synthesized by the same
conditions and procedures as those used for 3a using 5b. 1H NMR
(C6D6) for the methyl zinc complex: δ -0.71 (s, 3H, ZnCH3), 1.04
(d, J ) 7.2 Hz, 6H, CH3), 1.10 (d, J ) 7.2 Hz, 6H, CH3), 1.19 (t,
7.2 Hz, 6H, CH3), 2.53-2.70 (m, 4H, CH2), 2.95 (septet, J ) 7.2
Hz, 2H, CH), 7.02 (t, J ) 7.2 Hz, 1H, C6H3), 7.08 (d, J ) 7.2 Hz,
2H, C6H3), 7.09 (s, 2H, C6H2), 7.25 (AA′BB′, 1H, C6H4), 7.42
(AA′BB′, 1H, C6H4), 8.51 (s, 1H, NdCH). 13C{1H} NMR (C6D6):
δ -17.18 (ZnC), 15.00, 23.67, 24.40, 25.71, 29.19, 101.1 (m),
125.36, 126.04, 126.44, 128.08, 130.77, 126.86, 136.91, 140.49,
140.97, 141.02, 144.24, 144.82, 146.87, 146.91, 161.3 (m). 19F-
2
(dm, JCF ) 260 Hz), 137.25, 139.02, 140.83, 141.63, 143.9 (dm,
2
2JCF ) 250 Hz), 148.6 (dm, JCF ) 240 Hz), 148.84, 157.96. 19F-
3
4
{1H} NMR (C6D6): δ -82.61 (td, JFF ) 22 Hz, JFF ) 6.7 Hz),
3
3
-67.65 (m), -58.25 (t, JFF ) 20 Hz), -54.90 (dm, JFF ) 19
Hz). Anal. Calcd. for (C56H50F8N4): C, 72.24; H, 5.41; N, 6.02.
Found: C, 72.57; H, 5.37; N, 6.30.
Compound 5i. The compound was synthesized by conditions
and procedures similar to those used for 5a using 4c and
2,6-Me2C6H3N(Li)H. Diethyl ether was used as a solvent. A yellow
solid was obtained in 50% yield. Mp ) 124 °C. IR (NaCl): 3153
(N-H), 1656 (CdN) cm-1. 1H NMR (C6D6): δ 1.91 (s, 6H, CH3),
2.09 (s, 6H, CH3), 6.93 (d, J ) 7.6 Hz, 2H, C6H3), 7.00 (t, J ) 7.6
Hz, 1H, C6H3), 7.09 (s, 2H, C6H2), 7.33 (AA′BB′, 1H, C6H4), 7.53
(AA′BB′, 1H, C6H4), 8.24 (s, 1H, NdCH), 10.80 (s, 1H, NH). 13C-
{1H} NMR (C6D6): δ 18.73, 18.84, 102.7 (m), 126.83, 127.50,
127.63, 130.27, 131.1 (dm, 2JCF ) 240 Hz), 131.31, 135.40, 135.59,
135.62, 136.6 (dm, 2JCF ) 250 Hz), 138.57, 139.12, 140.88, 143.8
(dm, 2JCF ) 250 Hz), 148.6 (dm, 2JCF ) 240 Hz), 148.92, 157.81.
3
4
{1H} NMR (C6D6): δ -84.38 (td, JFF ) 22 Hz, JFF ) 8 Hz),
3
4
5
-62.45 (dt, JFF ) 16 Hz, JFF and JFF ) 8 Hz), -54.94 (ddd,
3JFF ) 22 and 16 Hz, JFF ) 6 Hz), -54.39 (ddd, JFF ) 22 Hz,
4
3
5JFF ) 8 Hz, JFF ) 6 Hz). The addition of SO2 gas gave an
4
intractable yellow solid.
Compound 3c. The compound was synthesized using the same
conditions and procedures as those used for 3a using 5c. 1H NMR
(C6D6) for the methyl zinc complex: δ -0.61 (s, 3H, ZnCH3), 1.02
(d, J ) 7.2 Hz, 6H, CH3), 1.08 (d, J ) 7.2 Hz, 6H, CH3), 2.22 (s,
6H, CH3), 2.97 (septet, J ) 7.2 Hz, 2H, CH), 6.98 (t, J ) 7.2 Hz,
1H, C6H3), 7.03 (d, J ) 7.2 Hz, 2H, C6H3), 7.06 (s, 2H, C6H2),
7.25 (AA′BB′, 1H, C6H4), 7.41 (AA′BB′, 1H, C6H4), 8.48 (s, 1H,
NdCH). 13C{1H} NMR (C6D6): δ -17.40 (ZnC), 19.12, 23.66,
24.33, 29.20, 30.43, 101.4 (m), 124.81, 126.01, 128.08, 128.45,
129.27, 130.77, 131.14, 131.18, 140.38, 140.95, 141.00, 143.71,
144.82, 148.17, 161.3 (m). 19F{1H} NMR (C6D6): δ -84.25 (td,
3
4
19F{1H} NMR (C6D6): δ -82.48 (td, JFF ) 22 Hz, JFF ) 7.1
3
3
Hz), -68.51 (m), -58.46 (t, JFF ) 18 Hz), -55.08 (dm, JFF
)
20 Hz). Anal. Calcd. for (C52H42F8N4): C, 71.39; H, 4.84; N, 6.40.
Found: C, 71.48; H, 4.51; N, 6.72.
Compound 3a. Compound 5a (0.200 g, 0.182 mmol) was
dissolved in toluene (2 mL), and Me2Zn (0.847 g, 2.0 M toluene
solution, 1.82 mmol) was added. The solution was stirred for 2
days at room temperature. The solvent was removed by vacuum to
give an orange solid, which is pure according to the analysis of
the NMR spectra. The yield was quantitative. 1H NMR (C6D6): δ
-0.61 (s, 3H, ZnCH3), 1.06 (d, J ) 7.2 Hz, 6H, CH3), 1.13 (d, J
) 7.2 Hz, 6H, CH3), 1.26 (d, J ) 7.2 Hz, 6H, CH3), 1.29 (d, J )
7.2 Hz, 6H, CH3), 3.02 (septet, J ) 7.2 Hz, 2H, CH), 3.37 (septet,
J ) 7.2 Hz, 2H, CH), 7.05 (t, J ) 7.6 Hz, 1H, C6H3), 7.10 (s, 2H,
C6H2), 7.17 (d, J ) 7.6 Hz, 2H, C6H3), 7.28 (AA′BB′, 1H, C6H4),
7.45 (AA′BB′, 1H, C6H4), 8.55 (s, 1H, NdCH). 13C{1H} NMR-
(C6D6): δ -16.92 (ZnC), 23.64, 24.31, 24.36, 29.25, 101.1 (m),
123.58, 125.93, 126.04, 128.52, 129.28, 130.79, 140.44, 140.97,
141.01, 141.68, 141.73, 144.53, 144.82, 145.18, 161.4 (m). 19F-
4
3
4
3JFF ) 22 Hz, JFF ) 8 Hz), -64.18 (dt, JFF ) 16 Hz, JFF and
5JFF ) 8 Hz), -54.96 (ddd, JFF ) 22 and 16 Hz, JFF ) 6 Hz),
3
4
3
5
4
1
-54.36 (ddd, JFF ) 22 Hz, JFF ) 8 Hz, JFF ) 6 Hz). H NMR
(C6D6) for 3c (A:(B or C) ) 0.25:0.75): δ 1.03 and 1.01 (d, J )
7.2 Hz, 6H, CH3), 1.18 and 1.21 (d, J ) 7.2 Hz, 6H, CH3), 1.52,
1.67, and 1.71 (s, 3H, SCH3), 2.16, 2.23, and 2.32 (s, 6H, CH3),
3.02 and 3.11 (septet, J ) 7.2 Hz, 2H, CH), 6.90-7.08 (m, 5H,
C6H3 and C6H2), 7.33 (AA′BB′, 1H, C6H4), 7.57 (AA′BB′, 1H,
C6H4), 8.42 and 8.46 (s, 1H, NdCH).
Compound 3d. The compound was synthesized by the same
conditions and procedures as those used for 3a using 5d. 1H NMR
(C6D6) for the methyl zinc complex: δ -0.67 (s, 3H, ZnCH3), 1.01
(t, J ) 7.6 Hz, 6H, CH3), 1.26 (d, J ) 7.2 Hz, 6H, CH3), 1.28 (d,
J ) 7.2 Hz, 6H, CH3), 2.33-2.52 (m, 4H, CH2), 3.34 (septet, J )
7.2 Hz, 2H, CH), 7.00 (s, 2H, C6H2), 7.06 (t, J ) 7.6 Hz, 1H,
C6H3), 7.18 (d, J ) 7.6 Hz, 2H, C6H3), 7.34 (AA′BB′, 1H, C6H4),
7.50 (AA′BB′, 1H, C6H4), 8.47 (s, 1H, NdCH). 13C{1H} NMR
(C6D6): δ -16.98 (ZnC), 15.10, 24.35, 25.41, 29.22, 101.2 (m),
123.55, 125.88, 128.93, 130.70, 135.45, 140.58, 140.63, 141.66,
141.71, 144.50, 145.22, 146.23, 161.4 (m). 19F{1H} NMR (C6D6):
3
4
{1H} NMR (C6D6): δ -84.23 (td, JFF ) 22 Hz, JFF ) 8 Hz),
3
4
5
-61.91 (dt, JFF ) 16 Hz, JFF and JFF ) 8 Hz), -55.02 (ddd,
3JFF ) 22 and 16 Hz, JFF ) 6 Hz), -54.07 (ddd, JFF ) 22 Hz,
4
3
5JFF ) 8 Hz, JFF ) 6 Hz). The freshly prepared methyl zinc
4
compound was dissolved in toluene (4 mL), and the flask containing
it was connected to a Schlenk line by a glass joint. The solution
was cooled to -10 °C and evacuated briefly. The SO2 gas, dried
in a flask (1 L) containing P2O5 overnight, was introduced through
the Schlenk line. The solution was stirred for 30 min at room
temperature. The solution was evacuated briefly to remove the
remaining SO2 gas, and the flask was brought into a glovebox. The
solution was filtered over Celite to remove small amounts of
insoluble impurities. Removal of the solvent gave a yellow solid.
3
4
3
δ -84.57 (td, JFF ) 22 Hz, JFF ) 8 Hz), -61.87 (dt, JFF ) 16
Hz, 4JFF and 5JFF ) 8 Hz), -55.28 (t, 3JFF ) 16 Hz), -53.70 (m).
1H NMR (C6D6) for 3d (A:(B or C):(C or B) ) 0.41:0.41:0.18): δ
0.98-1.45 (m, 18H, CH3), 1.55, 1.65, 1.72, and 1.93 (s, 3H, SCH3),
2.36-2.62 (m, 4H, CH2), 3.22-3.60 (m, 2H, CH), 6.79, 6.83, 6.84,
and 6.89 (s, 2H, C6H2), 7.01-7.22 (m, 3H, C6H3), 7.35 (AA′BB′,
1H, C6H4), 7.54 (AA′BB′, 1H, C6H4), 8.20, 8.26, and 8.30 (s, 1H,
NdCH).
1
The yield was quantitative. Analysis of the H NMR spectrum
indicated the presence of three isomers A, B (or C), and C (or B)
Inorganic Chemistry, Vol. 45, No. 10, 2006 4235

Bok et al.
Table 3. Crystallographic Parameters of 3c
Compound 3e. The compound was synthesized by the same
conditions and procedures as those used for 3a using 5e. 1H NMR
(C6D6) for the methyl zinc complex: δ -0.69 (s, 3H, ZnCH3), 0.97
(t, J ) 7.6 Hz, 6H, CH3), 1.18 (t, J ) 7.6 Hz, 6H, CH3), 2.37-
2.54 (m, 4H, CH2), 2.62-2.78 (m, 4H, CH2), 6.96 (s, 2H, C6H2),
7.03 (t, J ) 7.6 Hz, 1H, C6H3), 7.09 (d, 2H, C6H3), 7.30 (AA′BB′,
1H, C6H4), 7.47 (AA′BB′, 1H, C6H4), 8.44 (s, 1H, NdCH). 13C-
{1H} NMR (C6D6): δ -17.23 (ZnC), 15.01, 15.19, 25.42, 25.69,
101.2 (m), 125.31, 126.40, 128.06, 128.95, 130.63, 165.48, 136.83,
136.88, 140.57, 140.65, 144.17, 146.22, 146.94, 161.4 (m). 19F-
3c
formula
fw
C62H62F8N4O4S2Zn2‚(C4H10O)
1348.14
yellow
color
size (mm3)
a (Å)
0.60 × 0.55 × 0.45
10.983(4)
21.099(6)
28.304(10)
100.955(12)°
6439(4)
monoclinic
P21/n
1.391
4
0.885
50 137
b (Å)
c, Å
â, deg
V (Å3)
cryst syst
space group
3
4
{1H} NMR (C6D6): δ -84.69 (td, JFF ) 22 Hz, JFF ) 8 Hz),
3
4
5
-62.44 (dt, JFF ) 16 Hz, JFF and JFF ) 8 Hz), -55.18 (ddd,
D
Z
calcd (g cm-1
)
4
3
3JFF ) 22 and 16 Hz, JFF ) 6 Hz), -54.08 (ddd, JFF ) 22 Hz,
5JFF ) 8 Hz, 4JFF ) 6 Hz). 1H NMR (C6D6) for 3e (A:(B or C):(C
or B) ) 0.41:0.41:0.18): δ 0.85-1.40 (m, 12H, CH3), 1.48, 1.65,
and 1.71 (s, 3H, SCH3), 2.24-2.90 (m, 8H, CH2), 6.78, 6.83, 6.82,
and 6.86 (s, 2H, C6H2), 6.96-7.16 (m, 3H, C6H3), 7.32 (AA′BB′,
1H, C6H4), 7.54 (AA′BB′, 1H, C6H4), 8.20, 8.25, and 8.28 (s, 1H,
NdCH).
µ (mm-1
)
no. of data collected
no. of unique data
no. of variables
Ra (%)
13 769
784
0.1041
0.2742
Rwa (%)
GOF
1.004
Compound 3f. The compound was synthesized by the same
conditions and procedures as those used for 3a using 5f. 1H NMR
(C6D6) for the methyl zinc complex: δ -0.67 (s, 3H, ZnCH3), δ
0.95 (t, J ) 7.6 Hz, 6H, CH3), 2.19 (s, 6H, CH3), 2.27-2.44 (m,
4H, CH2), 6.95 (s, 2H, C6H2), 6.98 (t, J ) 7.6 Hz, 1H, C6H3), 7.03
(d, J ) 7.6 Hz, 2H, C6H3), 7.29 (AA′BB′, 1H, C6H4), 7.45 (AA′BB′,
1H, C6H4), 8.41 (s, 1H, NdCH). 13C{1H} NMR (C6D6): δ -17.41
(ZnC), 15.22, 19.15, 25.44, 101.4 (m), 124.77, 128.42, 128.95,
a Data collected with Mo KR radiation (λ(KR) ) 0.7107 Å), R(F) )
∑||Fo| - |Fc||/∑|Fo| with Fo > 2.0σ(I); Rw ) [∑[w(Fo - Fc )2]/
2
2
∑[w(Fo)2]2]1/2 with Fo > 2.0σ(I).
J ) 7.6 Hz, 2H, C6
H ), 7.26 (AA′BB′, 1H, C H ), 7.46 (AA′BB′,
3
6
4
1H, C6H4), 8.28 (s, 1H, NdCH). 13C{1H} NMR (C6D6): δ -17.39
(ZnC), 15.10, 18.80, 25.70, 101.3 (m), 125.30, 126.41, 127.50,
129.28, 129.30, 130.60, 130.68, 136.83, 136.89, 140.14, 140.41,
144.06, 147.03, 161.0 (m).
19F{1H} NMR (C6D6): δ -84.95 (td,
130.65, 131.10, 131.14, 135.42, 140.57, 140.61, 143.64, 146.20,
3
4
3
4
148.22, 161.3 (m). 19F{1H} NMR (C6D6): δ -84.54 (td, JFF
)
3JFF ) 22 Hz, JFF ) 8 Hz), -62.46 (dt, JFF ) 16 Hz, JFF and
4
3
4
5
3
4
22 Hz, JFF ) 8 Hz), -64.15 (dt, JFF ) 16 Hz, JFF and JFF ) 8
Hz), -55.20 (ddd, JFF ) 22 and 16 Hz, JFF ) 6 Hz), -54.14
5JFF ) 8 Hz), -55.43 (ddd, JFF ) 22 and 16 Hz, JFF ) 6 Hz),
3
4
3
5
4
1
-53.54 (ddd, JFF ) 22 Hz, JFF ) 8 Hz, JFF ) 6 Hz). H NMR
(C6D6) for 3h (A:(B or C):(C or B) ) 0.53:0.26:0.21): δ 1.10-
1.34 (m, 6H, CH2CH3), 1.42, 1.64, and 1.72 (s, 3H, SCH3), 1.89,
2.00, 2.09, and 2.18 (s, 6H, CH3), 2.50-2.92 (m, 4H, CH2), 6.64,
6.73, 6.78, and 6.82 (s, 2H, C6H2), 6.98-7.15 (m, 3H, C6H3), 7.30
(AA′BB′, 1H, C6H4), 7.47 (AA′BB′, 1H, C6H4), 8.14 and 8.17 (s,
1H, NdCH).
3
5
4
1
(ddd, JFF ) 22 Hz, JFF ) 8 Hz, JFF ) 6 Hz). H NMR (C6D6)
for 6f (A:(B or C):(C or B) ) 0.44:0.44:0.12): δ 0.86-1.17 (m,
6H, CH3), 1.38, 1.54, 1.69, and 1.74 (s, 3H, SCH3), 2.13, 2.24,
2.34, and 2.41 (s, 6H, CH3), 2.36-2.61 (m, 4H, CH2), 6.63, 6.73,
6.77, and 6.84 (s, 2H, C6H2), 6.98-7.14 (m, 3H, C6H3), 7.33
(AA′BB′, 1H, C6H4), 7.53 (AA′BB′, 1H, C6H4), 8.19, 8.25, and
8.29 (s, 1H, NdCH).
Compound 3i. The compound was synthesized by the same
conditions and procedures as those used for 3a using 5i. 1H NMR
(C6D6) for the methyl zinc complex: δ -0.72 (s, 3H, ZnCH3), 1.90
(s, 6H, CH3), 2.16 (s, 6H, CH3), 6.90 (s, 2H, C6H2), 6.98 (t, J )
7.6 Hz, 1H, C6H3), 7.03 (d, J ) 7.6 Hz, 2H, C6H3), 7.30 (AA′BB′,
1H, C6H4), 7.45 (AA′BB′, 1H, C6H4), 8.25 (s, 1H, NdCH). 13C-
{1H} NMR (C6D6): δ -17.40 (ZnC), 18.81, 19.17, 101.61 (m),
124.71, 128.40, 129.23, 129.27, 130.61, 130.68, 131.07, 131.12,
140.13, 140.38, 143.52, 147.03, 148.25, 148.29, 161.0 (m). 19F-
Compound 3g. The compound was synthesized by the same
conditions and procedures as those used for 3a using 5g. 1H NMR
(C6D6) for the methyl zinc complex: δ -0.70 (s, 3H, ZnCH3), 1.24
(d, J ) 7.2 Hz, 12H, CH3), 1.95 (s, 6H, CH3), 3.30 (septet, J ) 7.2
Hz, 2H, CH), 6.96 (s, 2H, C6H2), 7.06 (t, J ) 7.6 Hz, 1H, C6H3),
7.16 (s, J ) 7.6 Hz, 2H, C6H3), 7.34 (AA′BB′, 1H, C6H4), 7.50
(AA′BB′, 1H, C6H4), 8.31 (s, 1H, NdCH). 13C{1H} NMR (C6D6):
δ -17.26 (ZnC), 18.78, 24.25, 24.45, 29.16, 101.4 (m), 123.55,
125.87, 128.07, 128.67, 129.30, 130.68, 140.11, 140.32, 141.65,
141.70, 144.36, 145.24, 145.28, 147.06, 161.0 (m). 19F{1H} NMR
3
4
{1H} NMR (C6D6): δ -84.78 (td, JFF ) 22 Hz, JFF ) 8 Hz),
3
4
5
-64.14 (dt, JFF ) 16 Hz, JFF and JFF ) 8 Hz), -55.49 (ddd,
3
4
4
3
(C6D6): δ -84.78 (td, JFF ) 22 Hz, JFF ) 8 Hz), -61.83 (dt,
3JFF ) 22 and 16 Hz, JFF ) 6 Hz), -53.56 (ddd, JFF ) 22 Hz,
4
5
3
4
1
3JFF ) 16 Hz, JFF and JFF ) 8 Hz), -55.49 (ddd, JFF ) 22 and
5JFF ) 8 Hz, JFF ) 6 Hz). H NMR (C6D6) for 3i (A:(B or C):(C
or B) ) 0.57:0.25:0.18): δ 1.33, 1.51, 1.69, and 1.74 (s, 3H, SCH3),
1.89, 2.00, 2.08, 2.10, 2.17, 2.22, 2.26, and 2.41 (s, 12H, CH3),
6.64, 6.74, 6.78, and 6.85 (s, 2H, C6H2), 6.98-7.15 (m, 3H, C6H3),
7.31 (AA′BB′, 1H, C6H4), 7.47 (AA′BB′, 1H, C6H4), 8.14 and 8.16
(s, 1H, NdCH).
16 Hz, 4JFF ) 6 Hz), -53.18 (ddd, 3JFF ) 22 Hz, 5JFF ) 8 Hz, 4JFF
1
) 6 Hz). H NMR (C6D6) for 3g (A:(B or C):(C or B) ) 0.50:
0.39:0.11): δ 0.90-1.20 (m, 12H, CH2CH3), 1.31, 1.54, 1.62, and
1.84 (s, 3H, SCH3), 1.87, 1.99, 2.09, and 2.20 (s, 6H, CH3), 3.26,
3.42, and 3.49 (septet, J ) 7.2 Hz, 2H, CH), 6.63, 6.73, 6.77, and
6.84 (s, 2H, C6H2), 6.98-7.15 (m, 3H, C6H3), 7.30 (AA′BB′, 1H,
C6H4), 7.47 (AA′BB′, 1H, C6H4), 8.12, 8.15, and 8.16 (s, 1H, Nd
CH).
CO2/(Cyclohexene Oxide) Copolymerization. Into glassware
that fits into a bomb reactor (50 mL) were added, inside a glovebox,
the Zn complex (14 µmol of Zn) and cyclohexene oxide (8.0 mL,
79 mmol). After the glassware was placed in the bomb unit, the
reactor was assembled and brought out from the glovebox. The
reactor was immersed in an oil bath whose temperature had been
set to 80 °C. The CO2 gas was charged into the reactor to 14 bar.
After the solution was stirred for 2 h with a magnetic stirring bar
Compound 3h. The compound was synthesized by the same
conditions and procedures as those used for 3a using 5g. 1H NMR
(C6D6) for the methyl zinc complex: δ -0.85 (s, 3H, ZnCH3), 1.15
(t, J ) 7.6 Hz, 6H, CH3), 1.91 (s, 6H, CH3), 2.47-2.63 (m, 4H,
CH2), 6.90 (s, 2H, C6H2), 7.02 (t, J ) 7.6 Hz, 1H, C6H3), 7.09 (d,
4236 Inorganic Chemistry, Vol. 45, No. 10, 2006

CO2/(Cyclohexene Oxide) Copolymerization
at 80 °C, the CO2 gas was released and the reactor was disas-
sembled. When the pressure dropped below 11 bar, additional CO2
gas was charged. The viscous solution was poured into a flask
containing methanol, giving a white lump. After the lump was
broken, it was stirred over methanol overnight. The solid was
collected by decantation and dried under vacuum.
parameters. The hydrogen atoms were treated as idealized contribu-
tions. The crystal data and refinement results for 3c are summarized
in Table 3.
Acknowledgment. This work was supported by a Korea
Research Foundation Grant funded by the Korean Govern-
ment (MOEHRD, Basic Research Promotion Fund; KRF-
2005-015-C00233).
Crystallographic Studies. Crystals of 3c coated with grease
(Apiezon N) were mounted onto a thin glass fiber with epoxy glue
and placed in a cold nitrogen stream at 150(2) K on a Rigaku single-
crystal X-ray diffractometer. The structures were solved by direct
methods (SHELXL-97)18 and refined against all F2 data (SHELXL-
97). All non-hydrogen atoms were refined with anisotropic thermal
Supporting Information Available: Crystallographic data for
3c in CIF format. This material is available free of charge via the
Internet at http://pubs.acs.org.
(18) Sheldrick, G. M. SHELXL-97, Program for the Refinement of Crystal
Structures; University of Go¨ttingen: Go¨ttingen, Germany, 1997.
IC060060R
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