Synthesis and characterization of titanium(IV) complexes bearing monoanionic [O-NX] (X = O, S, Se) tridentate ligands and their behaviors in ethylene homo- And copolymerizaton with 1-hexene

Article abstract of DOI:10.1021/om060062j

A series of novel titanium(IV) complexes bearing monoanionic [O ^-NX] (X = O, S, Se) ligands is designed by sidearm approach. These complexes were synthesized, characterized, and employed as catalysts in ethylene homo- and copolymerization. X-ray diffraction studies on these new compounds reveal a distorted octahedral coordination of the central metal with the three chlorine ligands in a mer disposition. In the presence of modified methylaluminoxane (MMAO), they exhibit moderate to high activity and afford highly linear polyethylene. Variation of the sidearm, including different heteroatom and substituents, proves to modulate both the catalytic activity and the molecular weight of the resulting polyethylene. The complexes also show excellent capability in copolymerization of ethylene with 1-hexene.

Full text of DOI:10.1021/om060062j

Organometallics 2006, 25, 3259-3266
3259
Synthesis and Characterization of Titanium(IV) Complexes Bearing
Monoanionic [O-NX] (X ) O, S, Se) Tridentate Ligands and Their
Behaviors in Ethylene Homo- and Copolymerizaton with 1-Hexene
Cong Wang, Zhi Ma, Xiu-Li Sun,* Yuan Gao, Yang-Hui Guo, Yong Tang,* and
Li-Ping Shi
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry,
Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032, People’s Republic of China
ReceiVed January 21, 2006
A series of novel titanium(IV) complexes bearing monoanionic [O-NX] (X ) O, S, Se) ligands is
designed by sidearm approach. These complexes were synthesized, characterized, and employed as catalysts
in ethylene homo- and copolymerization. X-ray diffraction studies on these new compounds reveal a
distorted octahedral coordination of the central metal with the three chlorine ligands in a mer disposition.
In the presence of modified methylaluminoxane (MMAO), they exhibit moderate to high activity and
afford highly linear polyethylene. Variation of the sidearm, including different heteroatom and substituents,
proves to modulate both the catalytic activity and the molecular weight of the resulting polyethylene.
The complexes also show excellent capability in copolymerization of ethylene with 1-hexene.
titanium complexes I were excellent precatalysts for living
ethylene polymerization,9,10 living propylene polymerization
with excellent stereoselectivity,11 and living copolymerization
of ethylene with R-olefins.12a The synthesis of functional and
block copolymers of propylene can also be realized using such
catalytic systems.13 Gibson et al. reported that salicylaldiminato
ligands could also be employed to stabilize Cr(III) catalysts.14
Introduction
During the last two decades, single-site catalytic systems
based on the metallocene complexes of group IV metals have
been extensively studied.1 Recently, there has been a growing
interest in developing new nonmetallocene catalysts, and in
expanding beyond the first half of the transition metal series
and various ligand backbones,2-4 as well as allowing access to
previously inaccessible polymers.4 Of the successful non-
metallocene catalysts developed,2-4 the metal complexes pos-
sessing phenoxyimine ligands are one of the promising ex-
amples.5 Nickel complexes bearing salicylaldiminato ligands
exhibited good tolerance to functional group and even remained
active for olefin polymerization in the presence of polar or
protonic solvents.6,7 Fujita’s group and Coates’ group described
a family of highly active group IV catalysts I bearing bis-
(salicylaldiminato) ligands8-13 (Scheme 1). They found that
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* To whom correspondence should be addressed. E-mail: tangy@
mail.sioc.ac.cn.
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10.1021/om060062j CCC: $33.50 © 2006 American Chemical Society
Publication on Web 05/19/2006

3260 Organometallics, Vol. 25, No. 13, 2006
Wang et al.
Scheme 1
Scheme 2
Sidearm approach has proven to be an efficient strategy for
the design of organometallic catalysts in organic synthesis.
Recently, Kol et al. showed that group IV complexes bearing
bis(phenolate) [O-NO-] and [O-NNO-] type ligands are good
olefin polymerization catalysts, in particular for the polymeri-
zation of 1-hexene.15-20 They found that the pendant amino
group of the ligand influenced strongly the activity in polym-
erization of 1-hexene.16 Gibson et al. reported that the activities
of Cr(III) catalysts, containing salicylaldininato ligands with
pendant donors, were higher than those of the corresponding
catalysts without sidearm donors.14 Nickel complexes bearing
salicylaldiminato ligands with a carbene as a pendant donor have
also been reported.21 In a previous study on ylide chemistry
and asymmetric catalysis, we also found strong sidearm effects
on selectivity and catalytic activity in some reactions.22 Recently,
we reported that catalysts bearing a [O-NP] ligand (II) (Scheme
1) were robust and highly active for ethylene homopolymeri-
zation and copolymerization with 1-hexene and with nor-
bornene.23 We also communicated that [O-NS] titanium com-
plexes24 were good catalysts for olefin polymerization.25 To
further understand the sidearm effects of the extra donor and
the structure-reactivity relationship of the catalysts, we herein
report the synthesis and characterization of a series of titanium
complexes bearing phenoxyimines with O- (5a-5d), S- (5e-
5l), or Se-donors (5m) as sidearms, as well as the behaviors of
such complexes in ethylene polymerization and copolymeriza-
tion with 1-hexene.
Results and Discussion
1. Design and Synthesis of Ligands and Complexes. As
described by Fujita8 and Coates,11a bis(salicylaldiminato) tita-
nium complexes I showed high performance in ethylene
polymerization. We proposed that the introduction of a sidearm
group Z containing a donor atom would lead to the formation
of mono(salicylaldiminato) titanium complexes III, as shown
in Scheme 2. Complexes III are open for the coordination and
insertion of R-olefin, beneficial to ethylene copolymerization
with an R-olefin or a bulky olefin. Therefore, different sidearms
(O, S, Se) with various electronic and sterically hindered
substituents were selected for study.
Ligand Synthesis. The synthetic route for the ligands is
shown in Scheme 3. Treatment of phenols 2a-2d, benzenethiols
2e-2l, and benzeneselenol 2m with 1 equiv of KOH and
1-chloro-2-nitrobenzene at 90 °C for 5 h afforded nitrobenzene
derivatives 3a-3m. Nitrobenzenes 3a-3m were reduced by Zn/
HOAc, and products 4a-4m were collected, which could be
used directly for the next step without further purification.
Condensation of salicylal 1a or 1b8b,26 with anilines 4 afforded
tridentate ligands L1-L14 in 60-90% yields. The procedure
for preparation of imines L1-L14 is very simple and environ-
mental friendly: a mixture of the aniline and aldehyde 1a or
1b was refluxed for several hours and cooled to room temper-
ature after the reaction was complete, and the solid was collected
as the pure imines. In addition, the mother liquor could be
recycled.
Synthesis of Complexes. The ligands were deprotonated by
1.0 equiv of KH, followed by treating with 1.0 equiv of TiCl4
in toluene at room temperature, to afford the desired titanium
complexes 5a-5n in good to high yields. The purification of
the complexes was performed by recrystallization from toluene
upon cooling to -30 °C except for complex 5n, which was
recrystallized from a mixture of dichloromethane and hexane.
It is worthy to note that only the monoligated complexes were
isolated even if 1.0 equiv of excess ligand was added in the
reaction.
2. Characterization of Complexes. Complexes 5a-5n were
characterized by NMR, IR, and elemental analysis. Crystals of
5a, 5e, 5g, and 5i suitable for X-ray structure determination
were developed from toluene, and a crystal of 5n was obtained
from dichloromethane/hexane solution. As shown in Figures
1-5, complexes 5a, 5e, 5g, 5i, and 5n feature a distorted
octahedral coordination of the titanium with the three chlorine
ligands in a mer disposition, which is a good orientation for
olefin insertion and thus favorable for polymerization. The
selected bond lengths and angles are listed in Table 1. As shown
in Figure 1, the bond angle sum of Ti-O1-C22 (125.2°), Ti-
O1-C5 (117.4°), and C5-O1-C22 (117.0°) in 5a is nearly
360°. The torsion angle of Ti-O1-C22-C27 is 89.7°, and C22,
(15) Tshuva, E. Y.; Versano, M.; Goldberg, I.; Kol, M.; Weitman, H.;
Goldschimdt, Z. Inorg. Chem. Commun. 1999, 2, 371-373
(16) Tshuva, E. Y.; Goldberg, I.; Kol, M.; Weitman, H.; Goldschimdt,
Z. Chem. Commun. 2000, 379-380.
(17) Tshuva, E. Y.; Goldberg, I.; Kol, M.; Goldschimdt, Z. Inorg. Chem.
Commun. 2000, 3, 611-614
(18) Tshuva, E. Y.; Goldberg, I.; Kol, M.; Goldschimdt, Z. Chem.
Commun. 2001, 2120-2121.
(19) Tshuva, E. Y.; Groysman, S.; Goldberg, I.; Kol, M.; Goldschimdt,
Z. Organometallic 2002, 21, 662-670.
(20) Tshuva, E. Y.; Goldberg, I.; Kol, M. J. Am. Chem. Soc. 2000, 122,
10706-10707.
(21) Li, W. F.; Sun, H. M.; Chen, M. Z.; Wang, Z. G.; Hu, D. M.; Shen,
Q.; Zhang, Y. Organometallics 2005, 24, 5925-5928.
(22) (a) Zhou, J.; Tang, Y. J. Am. Chem. Soc. 2002, 124, 9030-9031.
(b) Zhou, J.; Ye, M. C.; Huang, Z. Z.; Tang, Y. J. Org. Chem. 2004, 69,
1309. (c) Ye, S.; Huang, Z. Z.; Xia, C. A.; Tang, Y.; Dai, L. X. J. Am.
Chem. Soc. 2002, 124, 2432-2433. (d) Zhou, J.; Tang, Y. Chem. Soc. ReV.
2005, 34, 664-676. (e) Huang, Z.-Z.; Ye, S.; Xia, W.; Yu, Y.-H.; Tang,
Y. J. Org. Chem. 2002, 67, 3096-1303. (f) Liao, W.-W.; Li, K.; Tang, Y.
J. Am. Chem. Soc. 2003, 125, 13030-13031. (g) Zheng, J.-C.; Liao, W.-
W.; Tang, Y.; Sun, X.-L.; Dai, L.-X. J. Am. Chem. Soc. 2005, 127, 12222-
12223.
(23) Hu, W. Q.; Sun, X. L.; Wang, C.; Gao, Y.; Tang, Y.; Shi, L. P.;
Wei, X.; Sun, J.; Dai, H. L.; Yao, X. L.; Wang, X. R. Organometallics
2004, 23, 1684-1688.
(24) For sulfur-containing complexes as olefin polymerzation catalysts,
please see: (a) Linden, A. van der C.; Schaverien, J.; Meijboom, N.; Ganter,
C.; Orpen, A. G. J. Am. Chem. Soc. 1995, 117, 3008-3021. (b) Graf, D.
D.; Schrock, R. R.; Davis, W. M.; Stumpf, R. Organometallics 1999, 18,
843-852. (c) Gibson, V. C.; Long, Nicholas, J.; Martin, J.; Solan, G. A.;
Stichbury, J. C. J. Organomet. Chem. 1999, 590, 115-117. (d) Janas, Z.;
Jerzykiewicz, L. B.; Prybylak, K.; Sobta, P.; Szczegot, K. Eur. J. Inorg.
Chem. 2004, 1639-1645. (e) Janas, Z.; Jerzykiewicz, L. B.; Richards, R.
L.; Sobota, P. Chem. Commun. 1999, 1015-1016. (f) Takaoki, K.; Miyatake,
T. Maromol. Symp. 2000, 157, 251-257. (g) Tshuva, E. Y.; Groysman, S.;
Goldberg, I.; Kol, M. Organometallics 2002, 21, 662-670.
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W.; Shi, L. P.; Tang, Y. Macromol. Rapid Commun. 2005, 26, 1609-1614.
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Zepp, C. M. J. Org. Chem. 1994, 59, 1939-1942.

Titanium(IV) Complexes Bearing [O-NX] (X ) O, S, Se)
Organometallics, Vol. 25, No. 13, 2006 3261
Scheme 3
Ti, C5, and O1 are coplanar. These facts revealed that O1 atom
is sp2 hybridization and the phenyl group is nearly perpendicular
to the N1-Ti-O1 plane in 5a. The molecular structures of
sulfur-containing complexes 5e, 5g, 5i, and 5n (Figures 2-4)
are similar, but they are different from that of the oxygen-
containing complex 5a. For example, the bond angles of Ti-
S-C22, Ti-S-C1, and C1-S-C22 in 5e are 115.4°, 98.9°,
and 103.3°, respectively, and the sum is 317.8°, suggesting that
the S atom in 5e is sp3-hybridized. As a result, the phenyl group
in 5e deviated from the [O-NS] plane. The Ti-Cl bond lengths
in complexes 5e, 5g, 5i, and 5n are shorter than those of the
corresponding Ti-Cl bond in 5a, suggesting that the electron
donation is reduced by using sulfur ligands instead of oxygen
Figure 3. Molecular structure of complex 5g.
Figure 1. Molecular structure of complex 5a.
Figure 2. Molecular structure of complex 5e.
Figure 4. Molecular structure of complex 5i.

3262 Organometallics, Vol. 25, No. 13, 2006
Table 1. Selected Bond Lengths (Å) and Angles (deg) of Complexes 5a, 5e, 5g, 5i, and 5n
Wang et al.
5a
5e
5g
5i
5n
Ti-O(2)
1.806(4)
2.249(5)
2.219(5)
Ti-O(1)
1.7910(19)
2.198(2)
2.5908
1.791(4)
2.181(5)
2.622(2)
2.2889(19)
2.273(2)
1.8030(18)
2.164(2)
2.6044(9)
2.3088(9)
2.2901(9)
2.2952(9)
84.40(8)
98.43(7)
86.75(6)
108.12(7)
167.47(6)
91.82(3)
91.73(7)
86.39(6)
167.12(4)
92.52(3)
1.798(8)
2.177(8)
2.591(3)
2.334(4)
2.256(4)
2.285(4)
85.9(3)
96.3(3)
84.5(3)
106.5(2)
167.5(3)
95.0(2)
Ti-N(1)
Ti-S(1)
Ti-Cl(1)
2.296(2)
2.385(2)
2.348(2)
2.2509(10)
2.2887(10)
2.3430(10)
86.44(8)
106.21(7)
167.35(7)
92.76(7)
83.81(7)
95.79(4)
96.48(7)
83.01(6)
94.84(4)
163.38(4)
Ti-Cl(2)
Ti-Cl(3)
2.321(2)
O(1)-Ti-N(1)
O(1)-Ti-Cl(1)
N(1)-Ti-Cl(1)
O(1)-Ti-Cl(2)
N(1)-Ti-Cl(2)
Cl(1)-Ti-Cl(2)
O(1)-Ti-Cl(3)
N(1)-Ti-Cl(3)
Cl(1)-Ti-Cl(3)
Cl(2)-Ti-Cl(3)
O(2)-Ti-N(1)
O(2)-Ti-O(1)
O(2)-Ti-Cl(1)
O(2)-Ti-Cl(3)
O(2)-Ti-Cl(2)
O(1)-Ti-S(1)
N(1)-Ti-S(1)
Cl(1)-Ti-S(1)
Cl(2)-Ti-S(1)
Cl(3)-Ti-S(1)
72.83(17)
97.21(12)
169.85(15)
83.88(14)
83.91(14)
93.26(8)
83.40(14)
86.33(14)
94.58(8)
165.80(9)
85.69(18)
158.32(17)
104.35(15)
92.56(16)
96.95(16)
84.49(18)
92.03(14)
85.70(13)
105.98(14)
169.52(15)
94.36(8)
100.40(14)
84.32(13)
163.22(8)
93.02(7)
94.0(3)
83.7(3)
163.8(1)
94.00(2)
164.04(7)
77.79(6)
89.55(4)
87.99(4)
79.36(3)
161.51(14)
77.02(14)
86.31(6)
92.51(7)
78.32(7)
161.15(7)
76.77(6)
79.94(3)
90.72(3)
87.88(3)
163.9(2)
78.3(2)
79.38(1)
89.4(1)
87.3(1)
ligands. These results showed that the sidearm could readily
modulate the spatial and the electronic properties of the active
site for polymerization and thus tune the activity of catalyst as
well as the capability for copolymerization as shown later.
3. Ethylene Homopolymerization. The performance of
complexes 5a-5n on ethylene polymerization is summarized
in Table 2. These complexes showed moderate to high activity
for ethylene polymerization in the presence of MMAO (modified
methylaluminoxane), depending on the pendant groups. The
results indicated that both the property of the donor atom and
the substituents on the sidearm significantly affected their
behaviors in ethylene polymerization.
(i) Effects of Sidearms. As shown in Table 2, the donor
atoms affect the catalytic behavior significantly in ethylene
polymerization, in both activity and molecular weight of
polyethylene. For example, complexes 5a-5d, with a pendant
group containing an oxygen donor, gave only moderate activity
(entries 1, 4-7). However, complexes 5e-5m, with a pendant
group containing sulfur and selenium donors, respectively,
showed much higher activity than the corresponding O-
sidearmed complexes under the same polymerization conditions
(entries 2-3, 8, and 13-15). In addition, the molecular weight
(Mw) of the polyethylene obtained by complexes 5a, 5e, and
5m significantly increased in the order of donor atom: O < S
< Se. These results suggested that both the steric hindrance
and electronic effects were probably the factors that influenced
the behaviors of the complexes in ethylene polymerization. As
shown in Figures 1-5, the molecular structures of S-containing
complexes 5e, 5g, 5i, and 5n are very different from that of
O-sidearmed complex 5a. The deviation of the aryl group in
the sidearms of compounds 5e, 5g, 5i, and 5n resulted in less
steric hindrance than complex 5a (Figures 1-5), beneficial to
chain growth and reduction of chain transfer in ethylene
polymerization and thus increased the activities of catalysts and
the molecular weights of polymers. These steric effects were
also consistent with the following experimental results: increas-
ing the steric hindrance by replacing H at the ortho position of
the phenyl group in the sidearm with Cl, Me, or i-Pr decreased
the catalytic activity greatly and increased the molecular weights
i
in the order R1 ) H, Cl, Me, Pr (entries 4-8 and 13-15).
Strong electronic effects of substitutes on the sidearmed aryl
group were not observed. For example, the complexes both with
an electron-deficient group (5f, 5g) and with an electron-rich
group (5h, 5i) on the sidearm showed high and similar activity
for ethylene polymerization (entries 9-12). During the polym-
erization, we observed that the color of 5e and 5m in toluene
solution changed from red to green (Ti(III)),27 while the color
of solution 5a changed from red to yellow28 upon activation
with MMAO under the same conditions. These results suggested
that different active species might be formed in the olefin
polymerization using O-sidearmed and S-sidearmed complexes
as precatalysts. This is also a possible reason for the different
olefin polymerization behaviors of the complexes with O- and
S-pendant groups. A clear mechanism awaits further investiga-
tion.
Noticeably, complex 5n showed much lower activity than
5e, probably due to its poor solubility in toluene. In addition,
molecular weight distribution of the polyethylene obtained by
complexes 5e-5l containing sulfur donors ranged from 1.7 to
(27) Eisch, J. J.; Pombrik, S. I.; Zheng, G. X. Organometallics 1993,
12, 3856-3863.
(28) Mahanthappa, M. K.; Cole, A. P.; Waymouth, R. M. Organo-
metallics 2004, 23, 836-845.
Figure 5. Molecular structure of complex 5n.

Titanium(IV) Complexes Bearing [O-NX] (X ) O, S, Se)
Organometallics, Vol. 25, No. 13, 2006 3263
Table 2. Results of the Ethylene Polymerization Assaysa
Table 4. Results of Ethylene Copolymerization with
1-Hexene Assaysa
a Polymerization conditions: 7 µmol of catalyst in 50 mL of toluene;
MMAO/Ti ) 500; ethylene pressure, 0.1 MPa; reaction time, 15 min.
b Temperature of the bath. c 105 g polymer mol-1 Ti-1 h-1 atm-1 d Deter-
.
mined by GPC, × 10-4
.
e 1-Hexene incoporation in copolymer, determined
by 13C NMR. f 3.5 µmol of catalyst; toluene, 50 mL.
atm-1, entry 1). The molecular weight of the polyethylene
proved to be sensitive to the Al/Ti ratio and increased with the
decrease of the Al/Ti ratio (entries 1-5), suggesting that there
existed chain transfers to aluminum compounds in the olefin
polymerization.
The effect of the polymerization temperature on the behavior
of catalyst 5e was also studied. Similar to the titanium complex
bearing the [N-OP] ligand,23 complex 5e proved thermally
stable from -5 to 80 °C (entries 2, 6-8). The maximum activity
of complex 5e was achieved at 30-50 °C (entries 2, 7), and
the catalytic activity was maintained at a high level even when
the temperature was lowered to -5 °C (entry 6) or elevated to
80 °C (entry 8). GPC studies of the polyethylene showed that
the Mw of the polymer was temperature-dependent. With the
increase of the temperature, the Mw of the polymer decreased
sharply from 59.8 × 104 g/mol at -5 °C to 1.36 × 104 g/mol
at 80 °C, indicating that the high polymerization temperature
promoted the chain transfer reaction. In our screened conditions,
the highest molecular weight was obtained at -5 °C (entry 6).
a Polymerization conditions: 3.5 µmol of catalyst in 50 mL of toluene;
[Al]/[Ti] ) 500; ethylene pressure, 0.1 MPa at 50 °C (oil bath temperature).
b 106 g PE mol-1 Ti-1 h-1 atm-1
of catalyst was used.
.
.
c Determined by GPC; × 10-4 d 10 µmol
Table 3. Effects of Ethylene Polymerization Conditionsa
d
d
d
entry T (°C)b [Al]/[Ti] yield (g) activity c
Mn
Mw
Mw/Mn
1
2
3
4
5
6
7
8
50
50
50
50
50
-5
30
80
100
500
1000
1500
2000
500
0.550
1.097
1.149
1.182
1.042
0.526
1.072
0.420
1.88
3.73
3.93
4.04
3.56
1.80
3.67
1.44
2.25
4.02
1.78
2.36
2.36
2.58
2.44
1.86
2.66
2.47
0.992 2.34
0.859 2.03
0.699 1.80
0.541 1.32
32.2
1.61
0.552 1.36
The melting point (Tm) of the polymers obtained by complex
5e is higher than 133 °C, which is the classical Tm for HDPE
(high-density polyethylene). This was in full accordance with
the 13C NMR studies of the polyethylene, which showed no
branches on the polymer backbone.
59.8
4.27
500
500
a Polymerization conditions: 3.5 umol of catalyst 5e in 50 mL of toluene;
4. Ethylene Copolymerization with 1-Hexene. The perfor-
mance of titanium complexes 5 for copolymerization of ethylene
with 1-hexene is summarized in Table 4. Both the donor atoms
and substituents on the pendant group influenced the copolym-
erization activity as well as the molar percentage of the
comonomer incorporation. The titanium complexes 5e and 5m
with S and Se in the sidearm Z, respectively, were highly active
for copolymerization (entries 4 and 9). However, complex 5a,
with an O-donor as the sidearm, gave only low activity (entry
1). As shown in Table 4, the molecular weight of the copolymer
decreased in the order of donor atom O > S > Se. Compound
5e proved more favorable for the insertion of 1-hexene than 5a
and 5m. For example, the molar percentage of 1-hexene
incorporation in the copolymer obtained by both 5a and 5m
was much lower than that obtained by 5e (entries 1 and 9 vs
entry 4). Substituent R1 on the sidearm also influenced strongly
the catalytic behavior of the complexes. For instance, compound
ethylene pressure, 0.1 MPa; reaction time, 5 min. b Temperature of the bath.
c 106 g PE mol-1 Ti-1 h-1 atm-1
.
d Determined by GPC, × 10-4
.
3.1, indicating that they were single-site catalysts. Compound
5d gave a broad molecular weight distribution, and the reason
is unclear.
(ii) Effects of Polymerization Conditions. It was found that
the cocatalyst/catalyst molar ratio (Al/Ti ratio) did not influence
strongly the catalytic activity of complex 5e, unlike in other
single-site catalysts.1-4 As shown in Table 3, the activity of
complex 5e was 4.04 × 106 g PE mol-1 Ti-1 h-1 atm-1 at the
Al/Ti ratio of 1500 (entry 4). The activity decreased slightly
(3.73 × 106 g PE mol-1 Ti-1 h-1 atm-1, entry 2) when the
Al/Ti ratio was reduced to 500. Even when an extremely low
amount of MMAO (Al/Ti ratio ) 100) was used, compound
5e still showed high activity (1.88 × 106 g PE mol-1 Ti-1 h-1

3264 Organometallics, Vol. 25, No. 13, 2006
Wang et al.
solution was added a solution of titanium tetrachlorides (0.285 g,
1.5 mmol) in toluene (20 mL) dropwise over a period of 20 min at
room temperature. The resulting mixture was stirred overnight and
filtered, and the solid was washed with CH2Cl2 (30 mL × 3). The
combined organic filtrates were concentrated under reduced pressure
to ca. 30 mL and then were cooled to -30 °C overnight. The reddish
crystal was collected and dried in vacuo to give complex 5a.
Yield: 0.402 g (57%). 1H NMR (300 MHz, CDCl3): δ 8.80
(s, 1H, CHdN), 7.78 (dd, J ) 1.2, 7.5 Hz, 2H, Ar-H), 7.68 (d, J
) 2.1 Hz, 1H, Ar-H), 7.64-7.46 (m, 4H, Ar-H), 7.26-7.17 (m,
3H, Ar-H), 6.61 (dd, J ) 2.1, 7.8 Hz, 1H, Ar-H), 1.54 (s, 9H,
t-Bu), 1.33 (s, 9H, t-Bu). 13C NMR (75 MHz, CDCl3): δ 160.7,
158.2, 154.2, 153.3, 148.4, 136.4, 133.4, 132.7, 130.9, 130.6, 130.4,
128.9, 128.4, 128.2, 127.3, 125.2, 125.1, 123.8, 116.7, 115.2, 35.4,
34.8, 31.1, 29.8. IR (KBr) ν: 1591, 1491, 1457, 1360, 1173, 1022,
885. Anal. Calcd for C27H30NO2Cl3Ti: C, 58.64; H, 5.45; N, 2.52.
Found: C, 60.03; H, 5.76; N, 2.09.
5k, bearing methyl groups at the ortho positions, was almost
inactive for copolymerization, which was in sharp contrast to
the high activities of complexes 5e, 5f, and 5h (entries 4, 6-8).
Compounds 5f, 5h, and 5e gave similar catalytic activities and
molecular weights of polymer as well as 1-hexene incorporations
(entries 4, 6, 7), indicating that the electronic properties of R3
hardly affected the copolymerization behaviors.
The catalytic behaviors of these complexes for copolymeri-
zation also depended on the polymerization conditions. As
shown in Table 4, lowering the temperature increased the Mw
of copolymer but decreased the 1-hexene incorporations (entries
2, 3), probably because the ethylene solubility increased in
toluene at low temperature. The increased feed of 1-hexene
significantly improved the incorporation but slightly decreased
the copolymerization activity (entries 2, 4). Thus, the molar
percentage of 1-hexene incorporation could be tuned by
employing catalysts with different pendant Z groups as well as
the change of polymerization conditions.
[N-(3,5-Di-tert-butylsalicylidene)-2-(2,6-dichlorophenoxyl)-
anilinato]Ti(IV)Cl3 (5b). The same procedure as that for the
preparation of 5a was used. KH (0.069 g, 1.7 mmol), L2 (0.800 g,
1.7 mmol), and TiCl4 (0.323 g, 1.7 mmol) were used. Yield: 0.636
Conclusion
1
g (61%). H NMR (300 MHz, CDCl3): δ 8.84 (s, 1H, CHdN),
In summary, phenoxyimine ligands with pendant donor
groups and their monoligand titanium complexes have been
synthesized and characterized. The pendant group proved to
strongly influence the structure of the corresponding titanium
complexes as well as their behaviors in olefin polymerization.
Combined with MMAO, these complexes have exhibited
moderate to high activity for ethylene polymerization and
afforded highly linear polyethylene, even at extremely low Al/
Ti ratio and high temperature. In addition, they have also shown
excellent capability for ethylene copolymerization with 1-hex-
ene. Investigation of ethylene copolymerization with long chain
R-olefin and bulky olefins promoted by these complexes is in
progress.
7.73 (d, J ) 1.8 Hz, 1H, Ar-H); 7.58-7.45 (m, 4H, Ar-H), 7.31-
7.19 (m, 3H, Ar-H); 6.66 (d, J ) 7.5 Hz, 1H, Ar-H), 1.54
(s, 9H, t-Bu), 1.36 (s, 9H, t-Bu).13C NMR (75 MHz, CDCl3):
δ 162.0, 150.4, 148.0, 146.6, 137.8, 136.6, 136.3, 132.6, 130.7,
130.5, 129.9, 128.9, 128.6, 128.2, 126.7, 125.2, 125.0, 114.4, 109.7,
35.4, 34.7, 31.1, 29.7. IR (KBr) ν: 1594, 1558, 1548, 1489, 1453,
1427, 1224, 1026, 885, 861, 774, 744. Anal. Calcd for C27H28Cl5-
NO2Ti: C, 52.00; H, 4.53; N, 2.25. Found: C, 51.76; H, 4.77; N,
1.77.
[N-(3,5-Di-tert-butylsalicylidene)-2-(2,6-dimethylphenoxyl)-
anilinato]Ti(IV)Cl3 (5c). The same procedure as that for the
preparation of 5a was used. KH (0.28 g, 7 mmol), L3 (3.0 g, 7
mmol), and TiCl4 (1.77 g, 7 mmol) were used. Yield: 2.10 g (49%).
1H NMR (300 MHz, CDCl3): δ 8.79 (s, 1H, CHdN), 7.72 (d, J )
2.4 Hz, 1H, Ar-H), 7.53 (d, J ) 1.8 Hz, 2H, Ar-H); 7.24-7.16
(m, 5H, Ar-H), 6.60 (d, J ) 6.3 Hz, 1H, Ar-H), 2.51 (s, 6H,
Ar-CH3), 1.53 (s, 9H, t-Bu), 1.36 (s, 9H, t-Bu). 13C NMR (75
MHz, CDCl3): δ 164.2, 158.6, 151.5, 150.7, 140.2, 137.1, 137.0,
131.4, 128.9, 127.8, 127.2, 126.6, 125.1, 121.7, 120.8, 118.5, 113.7,
35.1, 34.2, 31.5, 29.4, 16.4. IR (KBr) ν: 2961, 1605, 1586, 1557,
1545, 1494, 1461, 1376, 1245, 988, 867, 750. Anal. Calcd for
C29H34Cl3NO2Ti: C, 59.74; H, 5.83; N, 2.40. Found: C, 58.40; H,
6.10; N, 2.06.
Experimental Section
All manipulations of air- and/or moisture-sensitive compounds
were performed under argon atmosphere using standard Schlenk
1
techniques. H NMR and 13C NMR spectra were recorded on a
Varian XL-300 MHz spectrometer with TMS as the internal
standard. Mass spectra were obtained using a HP5959A spectrom-
eter. IR spectra were recorded using a Nicolet AV-360 spectrometer.
Elemental analysis was performed by the Analytical Laboratory of
Shanghai Institute of Organic Chemistry (CAS). Mn, Mw, and Mw/
Mn values of polymers were determined using a Waters Alliance
GPC 2000 series at 150 °C (using polystyrene calibration, 1,2,4-
[N-(3,5-Di-tert-butylsalicylidene)-2-(2,6-di-isoproylphenoxyl)-
anilinato]Ti(IV)Cl3 (5d). The same procedure as that for the
preparation of 5a was used. KH (0.80 g, 2 mmol), L4 (0.960 g, 2
mmol), and TiCl4 (0.38 g, 2 mmol) were used. Yield: 0.932 g
(71%). 1H NMR (300 MHz, CDCl3): δ 8.79 (s, 1H, CHdN), 7.72
(d, J ) 2.4 Hz, 1H, Ar-H), 7.57-7.54 (m, 2H Ar-H), 7.38-7.19
(m, 5H, Ar-H), 6.61 (dd, J ) 1.5, 7.8 Hz, 1H, Ar-H), 3.81 (hapta,
2H, J ) 6.6 Hz, CH(CH3)2), 1.53 (s, 9H, t-Bu), 1.36 (s, 9H, t-Bu),
1.33 (d, J ) 7.2 Hz, 6H, CH(CH3)2), 0.95 (d, J ) 6.6 Hz, 6H,
CH(CH3)2). 13C NMR (75 MHz, CDCl3): δ 162.3, 153.5, 149.9,
148.0, 142.8, 136.3, 134.6, 132.8, 130.7, 130.0, 129.0, 128.6, 128.2,
127.2, 126.1, 125.2, 124.6, 116.5, 35.5, 34.8, 31.2, 29.8, 27.3, 24.9,
23.9. IR (KBr) ν: 1598, 1560, 1549, 1462, 1434, 1362, 1271, 1253,
1179, 875, 837, 728. Anal. Calcd for C33H42Cl3NO2Ti: C, 62.03;
H, 6.62; N, 2.19. Found: C, 61.64; H, 6.77; N, 1.79.
trichlorobenzene as the solvent at a flow rate of 1.0 mL/min). 13
C
NMR data for polymers were obtained using o-dichlorobenzene-
d4 as the solvent at 110 °C. Toluene, THF, and hexane were distilled
over sodium/benzophenone ketyl prior to use. Dichloromethane was
distilled over CaH2. Compounds 1a, 1b, 2a-2m, 3a-3m, and 4a-
4m were prepared according to the known procedure.29 Modified
methylaluminoxane (MMAO) was purchased from Akzo Chemical
as a 1.6 M toluene solution. Polymerization-grade ethylene was
purified by passing through Et3Al before use.
[N-(3,5-Di-tert-butylsalicylidene)-2-phenoxylanilinato]Ti(IV)-
Cl3 (5a). To a stirred suspension of KH (0.050 g, 1.25 mmol) in
THF (10 mL) at -78 °C was added dropwise a solution of L1
(0.501 g, 1.25 mmol) in THF (30 mL) in 10 min. The resulting
mixture was allowed to warm to room temperature and stirred for
2 h. The solvent was removed under reduced pressure, and the
residue was dissolved in toluene (80 mL). To this yellow, clear
[N-(3,5-Di-tert-butylsalicylidene)-2-phenysulfanylanilinato]-
Ti(IV)Cl3 (5e). The same procedure as that for the preparation of
5a was used. KH (0.160 g, 4 mmol), L5 (1.670 g), and TiCl4 (0.800
g, 4.2 mmol) were used. Yield: 1.81 g (77%). 1H NMR (300 MHz,
CDCl3): δ 8.87 (s, 1H, CHdN); 7.74 (d, J ) 1.5 Hz, 1H, Ar-H);
7.73-7.19 (m, 10H, Ar-H), 1.51 (s, 9H, t-Bu); 1.36 (s, 9H, t-Bu).
(29) Moors, G. G. I.; Harrington, J. K. J. Med. Chem. 1975, 18, 386-
391.

Titanium(IV) Complexes Bearing [O-NX] (X ) O, S, Se)
Organometallics, Vol. 25, No. 13, 2006 3265
13C NMR (75 MHz, CDCl3): δ 163.9 (CHdN), 151.6, 147.4, 136.3,
135.6, 135.0, 133.2, 132.2, 131.1, 130.4, 129.1, 129.0, 128.9, 128.8,
127.3, 125.4, 119.7, 35.4, 34.7, 31.2, 29.7. IR (KBr) ν: 1581, 1479,
1442, 1236, 1202, 1175, 865. Anal. Calcd for C27H30NOSCl3Ti:
C, 56.81; H, 5.30; N, 2.45. Found: C, 57.67; H, 5.73; N, 2.05.
[N-(3,5-Di-tert-butylsalicylidene)-2-(2,6-dimethylphenysulfanyl)-
anilinato] Ti(IV)Cl3 (5k). The same procedure as that for the
preparation of 5a was used. KH (0.065 g, 1.6 mmol), L11 (0.72 3
g, 1.6 mmol), and TiCl4 (0.31 g, 1.6 mmol) were used. Yield: 0.62
1
g (64%). H NMR (300 MHz, CD2Cl2): δ 8.91 (s, 1H, CHdN);
7.83 (d, J ) 2.4 Hz, 1H, Ar-H), 7.68-7.44 (m, 4H, Ar-H), 7.26-
7.09 (m, 4H, Ar-H), 2.29 (s, 6H, CH3); 1.53 (s, 9H, t-Bu); 1.41
(s, 9H, t-Bu). 13C NMR (75 MHz, CD2Cl2): δ 163.8 (CHdN),
161.4, 154.3, 154.1, 150.4, 137.7, 136.6, 135.0, 134.6, 132.9, 132.8,
132.1, 129.8, 129.1, 127.1, 119.4, 116.9, 37.2, 36.6, 32.7, 31.4,
20.6. IR (KBr) ν: 1582, 1536, 1472, 1374, 1276, 1246, 1179, 872.
Anal. Calcd for C29H34NOSCl3Ti: C, 58.14; H, 5.68; N, 2.33.
Found: C, 57.84; H, 5.43; N, 2.09.
[N-(3,5-Di-tert-butylsalicylidene)-2-(4-trifluoromethyl-
phenylsulfanyl)anilinato]Ti(IV)Cl3 (5f). The same procedure as
that for the preparation of 5a was used. KH (0.040 g, 1 mmol), L6
(0.485 g, 1 mmol), and TiCl4 (0.23 g, 1.2 mmol) were used. Yield:
0.510 g (78%). 1H NMR (300 MHz, CDCl3): δ 8.90 (s, 1H,
CHdN); 7.77 (d, J ) 2.1 Hz, 1H, Ar-H), 7.69-7.54 (m, 6H, Ar-
H), 7.40 (d, J ) 5.1 Hz, 2H, Ar-H), 7.23 (m, 1H, Ar-H), 1.52 (s,
9H, t-Bu); 1.34 (s, 9H, t-Bu). 19F NMR (282.3 MHz, CDCl3): δ
63.2. IR (KBr) ν: 1607, 1556, 1327, 1246, 1169, 1062, 1012, 876.
Anal. Calcd for C28H29NOF3SCl3Ti: C, 52.64; H, 4.58; N, 2.19.
Found: C, 52.95; H, 4.96; N, 1.90.
[N-(3,5-Di-tert-butylsalicylidene)-2-(2,6-di-isopropylphenysul-
fanyl)anilinato]Ti(IV)Cl3 (5l). The same procedure as that for the
preparation of 5a was used. KH (0.161 g, 4 mmol), L12 (2.00 g,
4 mmol), and TiCl4 (0.76 g, 4 mmol) were used. Yield: 1.83 g
(70%). 1H NMR (300 MHz, CDCl3): δ 8.54 (s, 1H, CHdN); 7.74
(d, J ) 1.8 Hz, 1H, Ar-H), 7.70 (d, J ) 7.5 Hz, 1H, Ar-H),
7.49-7.03 (m, 6H, Ar-H), 6.47 (d, J ) 8.1 Hz, 1H, Ar-H)), 3.57
(hapta, 2H, J ) 6.9 Hz, CH(CH3)2); 1.62 (s, 9H, t-Bu); 1.35 (s,
9H, t-Bu); 1.15 (d, J ) 14.7 Hz, 12H, CH(CH3)2). 13C NMR (75
MHz, CDCl3): δ 170.4 (CHdN), 160.3, 154.0, 147.2, 137.5, 132.2,
130.7, 130.1, 129.0, 128.2, 127.6, 126.8, 126.5, 125.9, 125.5, 125.2,
124.4, 35.4, 34.7, 31.9, 31.2, 29.8, 25.4, 24.1. IR (KBr) ν: 1598,
1560, 1549, 1462, 1362, 1271, 1179, 1002, 875. Anal. Calcd for
C33H42NOSCl3Ti: C, 60.51; H, 6.46; N, 2.14. Found: C, 59.38;
H, 7.04; N, 1.58.
[N-(3,5-Di-tert-butylsalicylidene)-2-(3-chlorophenysulfanyl)-
anilinato]Ti(IV)Cl3 (5g). The same procedure as that for the
preparation of 5a was used. KH (0.140 g, 3.5 mmol), L7 (1.581 g,
3.5 mmol), and TiCl4 (0.67 g, 3.5 mmol) were used. Yield: 1.60
1
g (76%). H NMR (300 MHz, CDCl3): δ 8.89 (s, 1H, CHdN);
7.75-7.53 (m, 6H, Ar-H), 7.29-7.15 (m, 4H, Ar-H), 1.52 (s,
9H, t-Bu); 1.37 (s, 9H, t-Bu). 13C NMR (75 MHz, CDCl3): δ 164.1
(CHdN), 151.7, 147.6, 136.7, 136.3, 135.9, 135.0, 133.4, 132.6,
131.3, 130.6, 130.2, 129.1, 129.0, 128.2, 128.1, 127.3,127.2, 124.3,
119.9, 35.4, 34.8, 31.2, 29.7. IR (KBr) ν: 1585, 1542, 1473, 1364,
1245, 1184, 870. Anal. Calcd for C27H29NOSCl4Ti: C, 53.58; H,
4.83; N, 2.33. Found: C, 54.36; H, 5.22; N, 2.11.
[N-(3,5-Di-tert-butylsalicylidene)-2-(4-methoxylphenysulfanyl)-
anilinato]Ti(IV)Cl3 (5h). The same procedure as that for the
preparation of 5a was used. KH (0.140 g, 3.5 mmol), L8 (1.56 g,
3.5 mmol), and TiCl4 (0.67 g, 3.5 mmol) were used. Yield: 1.53
[N-(3,5-Di-tert-butylsalicylidene)-2-phenylselanylanilinato]-
Ti(IV)Cl3 (5m). The same procedure as that for the preparation of
5a was used. KH (0.100 g, 2.5 mmol), L13 (1.15 g, 2.5 mmol),
and TiCl4 (0.475 g, 2.5 mmol) were used. Yield: 1.01 g (65%).
1H NMR (300 MHz, CDCl3): δ 8.79 (s, 1H, CHdN); 7.74-7.26
(m, 11H, Ar-H), 1.51 (s, 9H, t-Bu); 1.35 (s, 9H, t-Bu). 13C NMR
(75 MHz, CD2Cl3): δ 167.2 (CHdN), 163.0, 155.1, 149.6, 138.4,
137.8, 135.0, 134.9, 134.0, 133.1, 132.2, 132.0, 131.3, 130.9, 129.4,
126.1, 122.8, 37.1. 36.6, 32.8, 31.3. IR (KBr) ν: 1645, 1606, 1557,
1472, 1249, 853. Anal. Calcd for C27H30NOSeCl3Ti: C, 52.50; H,
4.90; N, 2.27. Found: C, 53.21; H, 5.37; N, 2.01.
1
g (71%). H NMR (300 MHz, CDCl3): δ 8.90 (s, 1H, CHdN);
7.74 (s, 1H, Ar-H), 7.60-7.54 (m, 4H, Ar-H), 7.46-7.33 (m,
3H, Ar-H), 6.88(d, J ) 5.7 Hz, 2H, Ar-H), 3.79 (s, 3H, OCH3);
1.52 (s, 9H, t-Bu); 1.36 (s, 9H, t-Bu). 13C NMR (75 MHz, CDCl3):
δ 163.9 (CHdN), 161.3, 160.4, 151.1, 147.4, 136.4, 134.7, 133.1,
131.7, 131.3, 131.1, 130.3, 127.3, 125.4, 119.5, 114.7, 55.4, 35.4,
34.8, 31.2, 29.7. IR (KBr) ν: 1614, 1593, 1494, 1463, 1388, 1250,
1180, 1026, 878. Anal. Calcd for C28H29NO2S Cl3Ti: C, 55.95; H,
5.33; N, 2.33. Found: C, 56.45; H, 5.41; N, 2.24.
[N-(3-tert-Butylsalicylidene)-2-phenylsulfanylanilinato]Ti(IV)-
Cl3 (5n). The same procedure as that for the preparation of 5a was
used. KH (0.100 g, 3 mmol), L14 (1.083 g, 3 mmol), and TiCl4
[N-(3,5-Di-tert-butylsalicylidene)-2-(3-methoxylphenysulfanyl)-
anilinato]Ti(IV)Cl3 (5i). The same procedure as that for the
preparation of 5a was used. KH (1.56 g, 3.5 mmol), L9 (1.56 g,
3.5 mmol), and TiCl4 (0.67 g, 3.5 mmol) were used. Yield: 1.78
1
(0.57 g, 3 mmol) were used. Yield: 1.1 g (71%). H NMR (300
MHz, CD2Cl2): δ 8.91 (s, 1H, CHdN); 7.76-7.64 (m, 6H, Ar-
H), 7.40-7.24 (m, 6H, Ar-H), 1.50 (s, 9H, t-Bu). 13C NMR (75
MHz, CD2Cl2): δ 165.7 (CHdN), 164.9, 153.5, 138.6, 137.5, 137.4,
137.0, 136.6, 134.3, 132.6, 130.9, 130.8, 129.5, 127.1, 126.6, 121.7,
37.0, 31.2. IR (KBr) ν: 1582, 1545, 1468, 1376, 1254. Anal. Calcd
for C23H22NOSCl3Ti: C, 53.67; H, 4.31; N, 2.72. Found: C, 54.19;
H, 4.37; N, 2.37.
1
g (85%). H NMR (300 MHz, CDCl3): δ 8.85 (s, 1H, CHdN);
7.73 (s, 1H, Ar-H), 7.64-7.54 (m, 5H, Ar-H), 7.26-7.22 (m,
1H, Ar-H), 6.90-6.83 (m, 3H, Ar-H), 3.73 (s, 3H, OCH3); 1.52
(s, 9H, t-Bu); 1.35 (s, 9H, t-Bu). 13C NMR (75 MHz, CDCl3): δ
163.9 (CHdN), 161.5, 159.7, 151.5, 147.4, 136.1, 136.0, 135.7,
133.1, 132.3, 131.3, 130.3, 129.9, 127.3, 125.4, 121.2, 119.7, 114.6,
55.4, 35.3, 34.7, 31.2, 29.7. IR (KBr) ν: 1591, 1541, 1476, 1362,
1286, 1246, 1185, 1043, 858. Anal. Calcd for C28H29NO2SCl3Ti:
C, 55.95; H, 5.33; N, 2.33. Found: C, 56.52; H, 5.44; N, 2.24.
Polymerization Procedure. To a 100 mL flame-dried flask
was added 50 mL of freshly distilled toluene (and the re-
quired amount of 1-hexene in the case of copolymerization) at the
desired polymerization temperature. After 10 min, MMAO was
added. The resulting mixture was stirred for a further 5 min, and
the precursor catalyst solution in toluene was injected via a
syringe. The polymerization was carried out for the desired
time and then quenched with concentrated HCl in ethanol (100 mL,
HCl/ethanol, 1:20, v/v). The precipitated polymer was collected,
washed with ethanol, and then dried overnight in a vacuum oven
at 50 °C.
[N-(3,5-Di-tert-butylsalicylidene)-2-(2,6-dichlorophenysulfanyl)-
anilinato]Ti(IV)Cl3 (5j). The same procedure as that for the
preparation of 5a was used. KH (0.075 g, 1.9 mmol), L10 (0.911
g, 1.9 mmol), and TiCl4 (0.38 g, 2 mmol) were used. Yield: 0.887
1
g (73%). H NMR (300 MHz, CD2Cl2): δ 8.85 (s, 1H, CHdN);
7.83 (d, J ) 2.4 Hz, 1H, Ar-H), 7.66-7.27 (m, 8H, Ar-H), 1.54
(s, 9H, t-Bu); 1.40 (s, 9H, t-Bu). 13C NMR (75 MHz, CDCl3): δ
163.9 (CHdN), 158.3, 145.9, 141.9, 140.5, 137.0, 131.4, 130.6,
128.9, 128.3, 127.0, 126.9, 126.4, 126.0, 124.3, 118.3, 118.1, 35.1,
34.1, 31.4, 29.4. IR (KBr) ν: 1645, 1597, 1540, 1473, 1423, 1270,
1183, 852. Anal. Calcd for C27H28NOSCl5Ti: C, 52.80; H, 4.47;
N, 2.24. Found: C, 52.26; H, 4.93; N, 1.70.
X-ray Structure Determination. Data collections for com-
plexes 5a, 5e, 5g, 5i, and 5n were performed at 20 °C on a Bruker
SMART diffractometer with graphite-monochromated Mo KR

3266 Organometallics, Vol. 25, No. 13, 2006
Table 5. Crystallographic Data and Refinement for Complexes 5a, 5e, 5g, 5i, and 5n
Wang et al.
5a
5e
5g
5i
5n
empirical formula
fw
C
37.50H42NO2Cl3Ti
C27H30NOSCl3Ti
570.83
293(2)
0.71073
monoclinic
P2(1)/c
12.663(2)
17.026(3)
13.131(2)
90
98.186(3).
90
2802.4(7)
4
1.353
0.686
C28H30NOCl7STi
724.64
293(2)
0.71073
monoclinic
P2(1)/n
12.846(5)
14.395(5)
19.068(6)
90
102.623(8)
90
3441(2)
4
1.399
0.875
C29H33NO2Cl6STi
720.2
293(2)
0.71073
monoclinic
P2(1)/c
14.8394(12)
13.6848(11)
17.5778(14)
90
111.990(2)
90
3309.9(5)
4
1.445
0.834
C23H22NOSCl3Ti
692.97
293(2)
0.71073
triclinic
P1h
11.748(7)
13.365(8)
13.646(8)
91.911(10)
91.691(10)
112.739(10)
1973(2)
2
514.73
293(2)
0.71073
monoclinic
P2(1)
8.758(4)
11.801(6)
11.899(6)
90
105.016(8)
90
1187.8(10)
2
temperature (K)
λ(Mo KR) (Å)
cryst syst
space group
a (Å)
b (Å)
c (Å)
R (deg)
â (deg)
γ (deg)
V (Å3)
Z
D
calcd (g/cm3)
1.167
0.450
726
1.439
0.801
528
absorp coeff (mm-1
F(000)
)
1184
1480
1480
cryst size (mm)
2θmax (deg)
0.680 × 0.521 × 0.505 0.945 × 0.459 × 0.176 0.283 × 0.207 × 0.125 0.345 × 0.3175 × 0.127 0.499 × 0.424 × 0.287
50
56.6
54
54
55.9
no. of reflens collected 9333
16 260
19 948
19232
2539
no. of indep reflens
goodness-of-fit on F2
final R indexes
6746 (Rint ) 0.1545)
6408 (Rint ) 0.1188)
6408 (Rint ) 0.1417)
6408 (Rint ) 0.0662)
2227 (Rint ) 0.0978)
1.057
0.904
0.748
0.938
1.023
0.0959
0.0530
0.0688
0.0493
0.0763
[I > 2σ(I)]
radiation (λ ) 0.71073 Å). The SADABS absorption correction
was applied. The structures were solved by direct methods and
refined on F2 by full-matix least-squares techniques with anisotropic
thermal parameters for non-hydrogen atoms. Hydrogen atoms were
placed at the calculated positions and were included in the structure
calculation without further refinement of the parameters. All
calculations were carried out using the SHELXS-97 program.
Crystal data and processing parameters for complexes 5a, 5e, 5g,
5i, and 5n are summarized in Table 5.
Acknowledgment. We are grateful for the financial support
from the Natural Sciences Foundation of China and the Science
and Technology Commission of Shanghai Municipality.
Supporting Information Available: X-ray crystallographic data
1
of 5a, 5e, 5g, 5i, and 5n; synthesis of ligands L1-L14; H and
13C NMR spectra of complexes 5a-5n. These materials are
available free of charge via the Internet at http://pubs.acs.org.
OM060062J