Synthesis, characterization and catalytic studies of aluminium complexes containing sulfonamido-oxazolinate or -pyrazolinate ligands

Article abstract of DOI:10.1016/j.jorganchem.2013.12.022

A series of sulfonamido-oxazolinate ligand precursors, HNSO ₂Ph^HOxa, HNSO₂Ph^MeOxa, HNSO ₂Ph^TriMeOxa, or sulfonamido-pyrazolinate ligand precursors, HNSO₂Ph^HPz^H, HNSO ₂Ph^MePz^H, HNSO₂Ph ^TriMePz^H, HNSO₂Ph^FPz^H, HNSO₂Ph^HPz^Me, HNSO₂Ph ^MePz^Me, HNSO₂Ph^TriMePz^Me, have been prepared. Treatment of ligand precursors, HNSO₂Ph ^AOxa or HNSO₂Ph^APz^B, with 1.1 equiv. of AlMe₃ in THF affords aluminium sulfonamido-oxazolinate dimethyl complexes, (NSO₂Ph^AOxa)AlMe₂ [A = H (1); A = Me (2); A = TriMe, (3)], or aluminium sulfonamido-pyrazolinate dimethyl complexes, (NSO₂Ph^APz^B)AlMe₂ [A = H, B = H (4); A = Me, B = H (5); A = TriMe, B = H (6); A = F, B = H (7); A = H, B = Me (8); A = Me, B = Me (9); A = TriMe, B = Me (10)]. The aluminium bis(sulfonamido-pyrazolinate) methyl complex 5′ was isolated from recrystallization of 5 as minor product. The molecular structures of compounds 2, 5′ and 8 were determined by single-crystal X-ray diffraction techniques. Their catalytic activities towards the ring opening polymerization of ε-caprolactone in the presence of benzyl alcohol are also under investigation.

Full text of DOI:10.1016/j.jorganchem.2013.12.022

Journal of Organometallic Chemistry 753 (2014) 9e19
Contents lists available at ScienceDirect
Journal of Organometallic Chemistry
journal homepage: www.elsevier.com/locate/jorganchem
Synthesis, characterization and catalytic studies of aluminium
complexes containing sulfonamidoeoxazolinate or epyrazolinate
ligands
*
Chi-Tien Chen , Chien-Hung Liao, Kuo-Fu Peng, Ming-Tsz Chen, Tzu-Lun Huang
Department of Chemistry, National Chung Hsing University, Taichung 402, Taiwan
a r t i c l e i n f o
a b s t r a c t
A series of sulfonamidoeoxazolinate ligand precursors, HNSO2PhHOxa, HNSO2PhMeOxa, HNSO2Ph-
TriMeOxa, or sulfonamidoepyrazolinate ligand precursors, HNSO2PhHPzH, HNSO2PhMePzH, HNSO2Ph-
TriMePzH, HNSO2PhFPzH, HNSO2PhHPzMe, HNSO2PhMePzMe, HNSO2PhTriMePzMe, have been prepared.
Treatment of ligand precursors, HNSO2PhAOxa or HNSO2PhAPzB, with 1.1 equiv. of AlMe3 in THF affords
aluminium sulfonamidoeoxazolinate dimethyl complexes, (NSO2PhAOxa)AlMe2 [A ¼ H (1); A ¼ Me (2);
A ¼ TriMe, (3)], or aluminium sulfonamidoepyrazolinate dimethyl complexes, (NSO2PhAPzB)AlMe2
[A ¼ H, B ¼ H (4); A ¼ Me, B ¼ H (5); A ¼ TriMe, B ¼ H (6); A ¼ F, B ¼ H (7); A ¼ H, B ¼ Me (8); A ¼ Me,
B ¼ Me (9); A ¼ TriMe, B ¼ Me (10)]. The aluminium bis(sulfonamidoepyrazolinate) methyl complex 50
was isolated from recrystallization of 5 as minor product. The molecular structures of compounds 2, 50
and 8 were determined by single-crystal X-ray diffraction techniques. Their catalytic activities towards
the ring opening polymerization of ε-caprolactone in the presence of benzyl alcohol are also under
investigation.
Article history:
Received 3 September 2013
Received in revised form
6 December 2013
Accepted 10 December 2013
Keywords:
Sulfonamidoeoxazolinate
Sulfonamidoepyrazolinate
Aluminium
ε-Caprolactone
Ring opening polymerization
Ó 2013 Elsevier B.V. All rights reserved.
1. Introduction
been prepared and displayed efficient catalytic activities for ROP of
ε-caprolactone, L-lactide or trimethyl carbonate by the Lin’s and
Aliphatic polyesters, prepared from various lactones and/or
lactides, having the thermoplastic, biocompatible and biodegrad-
able properties make them to be the leading candidates in
biomedical and pharmaceutical industries [1e5]. The major syn-
thesized method employed in industry to prepare these polyesters
has been the ring opening polymerization (ROP) using well-defined
metal complexes with auxiliary ligands. There is a number of
excellent initiators/catalysts have been examined for the ROP dur-
ing the past decade [6e14]. The main challenge in elaborating
catalytic systems effective for ROP is the development of novel
efficient metal catalysts to produce the polymers bearing the
properties of precisely molecular weight, narrow polydispersity
index (PDI), efficient rate and high enantio- or regio-selectivity
under mild conditions. Among these studies, the metal com-
plexes supported by sulfonate [15,16] or sulfonamido [18e23]
anionic multidentate ligands have been a focus of interest, mainly
due to their good catalytic activities for ROP of cyclic esters. The
magnesium complexes bearing sulfonate phenolate ligands have
Ko’s groups [15,16]. However, the reactivity of magnesium bis-
adduct complexes derived from bis-phenolate ligands show only
moderate activity in the ROP of L-lactide in the presence of addi-
tional alcohols [17]. The Lin’s group also reported the aluminium
complexes containing sulfonamido/Schiff base ligand are efficient
initiators for ROP of L-lactide in well-controlled fashion [19]. The
Mountford’s group reported that the metal complexes such as ti-
tanium [20], zirconium [20], aluminium [21] or indium [22],
bearing tetradentate bis(sulfonamide)amino ligands also showed
the well-controlled ROP of rac-lactide. Recently, some Group 1
metal complexes bearing cyclohexyl-backboned bis-sulfonamido
ligand displayed the modest stereo-selectivity and well-controlled
fashion for ROP of rac-lactide under lower temperature condition
were reported by Lin’s group [23].
In our previous reports, some zinc [24,25], aluminium [25] or
magnesium [26] anilidoeoxazolinate complexes, or aluminium
anilidoepyrazolinate complexes [28] have shown their catalytic
activities toward the ROP of ε-caprolactone or L-lactide. In view of
the potential application of metal sulfonate or sulfonamido com-
plexes in ROP, we are interested in exploring the catalytic behaviour
of the metal complexes bearing related sulfonamido ligands
derived from our previous works. On the other respect, the steric or
* Corresponding author.
E-mail addresses: ctchen@mail.nchu.edu.tw, ctchen@dragon.nchu.edu.tw
(C.-T. Chen).
0022-328X/$ e see front matter Ó 2013 Elsevier B.V. All rights reserved.
http://dx.doi.org/10.1016/j.jorganchem.2013.12.022

10
C.-T. Chen et al. / Journal of Organometallic Chemistry 753 (2014) 9e19
electronic sulfonamides in general are attractive synthetic targets
due to their relatively easy and simple preparation from the cor-
responding sulfonyl chlorides and related amines or anilines under
mild conditions. Although aluminium complexes containing
anionic multidentate ligands, such as b-diketiminates [29], anilido-
iminates [30,31], amidinates [32,33] or phosphino-iminates
[34,35], have been reported their catalytic activities for ROP of cy-
clic esters recently. However only few examples of aluminium
complexes containing sulfonamido groups have been applied in
ROP as initiators/catalysts [18,19,21]. Herein we report the syn-
thesis and structures of aluminium complexes containing sulfo-
namidoeoxazolinate or epyrazolinate ligands. Their catalytic
activities toward the ring opening polymerization of ε-caprolactone
in the presence of benzyl alcohol are also examined.
2. Results and discussion
2.1. Preparations of sulfonamide ligand precursors
A series of sulfonamidoeoxazolinate or epyrazolinate ligand
precursors [HNSO2PhROxa, PhR ¼ phenyl (R ¼ H), tolyl (R ¼ Me) or
mesityl (R ¼ TriMe), HNSO2PhRPzH, PhR ¼ phenyl (R ¼ H), tolyl
(R ¼ Me), mesityl (R ¼ TriMe) or 4-fluorophenyl (R ¼ F) and
HNSO2PhRPzMe, PhR ¼ phenyl (R ¼ H), tolyl (R ¼ Me) or mesityl
(R ¼ TriMe)] were prepared by the reactions of 2-(4,4-dimethyl-
4,5-dihydrooxazo-2-yl)-phenylamine, 1-(2-aminophenyl)pyrazole
or 1-(3,5-dimethyl-2-aminophenyl)pyrazole with 1.1 molar equiv-
alent of the corresponding substituted benzenesulfonyl chlorides
and triethylamine in dichloromethane at room temperature, as
shown in (Scheme 1). These ligand precursors were easily purified
by column chromatography and afforded the satisfied yields. The
NeH signals on 1H NMR spectra for these ligand precursors were
observed at the range of 12.29e12.56 ppm for oxazolinate sulfon-
amides and 8.68e10.10 ppm for pyrazolinateesulfonamides. Since
the NH of sulfonamides have been still reacted with excess sulfonyl
chlorides in the presence of base to form bis-sulfonamides, the bis-
pyrazole-sulfonamide by-product N(SO2PhR)2PzH [PhR ¼ phenyl
(R ¼ H), tolyl (R ¼ Me) or 4-fluorophenyl (R ¼ F)] could also be
Fig. 1. Molecular structure of one of the crystallographically independent molecules of
2. Hydrogen atoms are omitted for clarity. Selected bond lengths (A) and bond angles
ꢀ
(ꢀ): AleN(1), 1.961(3); AleN(2), 1.948(3); AleC(19), 1.961(4); AleC(20), 1.955(4); Se
O(2), 1.435(3); SeO(3), 1.439(3); SeN(2), 1.635(3); SeC(7), 1.763(4); N(1)eC(14),
1.292(5); N(2)eC(1), 1.416(5); C(1)eC(6), 1.411(5); C(6)eC(14), 1.452(5); N(1)eAleN(2),
90.69(13); C(19)eAleC(20), 116.63(19); N(2)eAleC(19), 117.22(15); N(2)eAleC(20),
115.55(17); N(1)eAleC(19), 105.29(16); N(1)eAleC(20), 106.59(16); O(2)eSeO(3),
117.86(16); N(2)eSeC(7), 107.40(16).
observed and collected with 7e17% isolated yields upon preparing
the target compounds of HNSO2PhRPzH [PhR ¼ phenyl (R ¼ H), tolyl
(R ¼ Me) or 4-fluorophenyl (R ¼ F)], as shown in (Scheme S1). All of
these sulfonamido ligand precursors and some bis-sulfonamides
Scheme 1. Preparation of ligand precursors and complexes 1e10.

C.-T. Chen et al. / Journal of Organometallic Chemistry 753 (2014) 9e19
11
0
ꢀ
ꢀ
Fig. 2. Molecular structure of complex 5 . Hydrogen atoms on carbon atoms omitted for clarity. Selected bond lengths (A) and bond angles ( ): AleC(17), 1.963(4); AleN(1),
2.0859(19); AleN(3), 1.922(2); AleN(1A), 2.0859(19); AleN(3A), 1.922(2); SeO(1), 1.4434(17); SeO(2), 1.4472(17); SeN(3), 1.6090(19); SeC(7), 1.770(2); N(1)eAleN(1A), 172.28(12);
N(1)eAleN(3), 91.03(8); N(1)eAleN(3A), 84.15(8); N(3)eAleN(3A), 102.78(12); C(17)eAleN(1), 93.86(6); C(17)eAleN(3), 128.61(6); O(2)eSeO(3), 117.71(10); N(3)eSeC(7),
105.99(10).
ꢀ
were characterized by NMR spectroscopy as well as elemental
analysis. The suitable crystals for the structural refinement of pyr-
azole bis-sulfonamide N(SO2PhF)2PzH were isolated from concen-
trated dichloromethane solution, and the molecular structure was
depicted in Fig. S1.
oxazolinate [25] [1.917(5)e1.963(1) A for AleNoxazoline, 92.65(8)e
93.66(8)ꢀ for
[92.65(8)e95.51(18)ꢀ for
NoxazoleeAleNanilido] or anilidoeimino [30,38]
N
imineeAleNanilido and 111.6(2)e
116.70(1)ꢀ for CmethyleAleCmethyl] complexes. The bond distance of
AleNsulfonamide is comparable with those found in aluminium
ꢀ
Treatment of ten oxazolinate- or pyrazolinate-based sulfona-
mido ligand precursors with 1.1 molar equivalent of AlMe3 by
alkane elimination in THF at room temperature for 1 h affords the
desired aluminium dimethyl complexes 1e10 in moderate yields
respectively. The disappearance of the NeH signal of sulfonamide
and the appearance of the resonance for protons of methyl groups
in the high-field region are consistent with the structures proposed
in (Scheme 1). Due to the symmetric environment around the
metal centre, one singlet corresponding to two methyl groups on
the metal centre was observed in each case for these aluminium
complexes. The 27Al chemical shifts for di-alkyl complexes 1e10
appearing around the range of 103.8e142.0 ppm are within the
expected region for a four-coordinate aluminium species in solu-
tion (ca. 60e180 ppm) [36], especially for our previous work
{102.1e146.8 ppm for anilidoeoxazolinate aluminium complexes
[37] and 145.2e145.5 ppm for anilidoepyrazolinate aluminium
complexes [28]}. Complexes 1e10 were all characterized by NMR
spectroscopy as well as elemental analyses. However, attempts to
synthesize related aluminium complexes containing alkoxide
group (i.e. benzoxide or isopropoxide) have been proved
unsuccessful.
complexes containing sulfonamido ligands [1.858(2)e1.952(2) A
for AleNsulfonamide] [18,19,21].
Trace crystals were collected upon recrystallizing 5 from the
concentrated toluene solution at room temperature in few days.
The molecular structure of 50 is depicted in Fig. 2. The structure
demonstrates a mononuclear five-coordinated aluminium com-
plex, where the metal centre is coordinated by one methyl group
and two pyrazolylesulfonamido groups. Based on the
s-value
[s
¼ ( )/60] [40], the central aluminium adopts a distorted
b
ꢁ
a
Suitable crystals for structure determination of 2 were obtained
from dichloromethane/hexane solution. The molecular structure is
depicted in Fig. 1. The structure of 2 demonstrates a mononuclear
form and the aluminium centre adopts a distorted tetrahedral ge-
ometry with the metal centre coordinated by two methyl groups
and two nitrogen donor atoms of the oxazolinate and sulfonamido
groups.
N(1) ¼ 1.961(3) A] and AleNsulfonamide [AleN(2) ¼ 1.948(3) A] bond
distances might result from the -donation ability of the anionic
The
difference
between
AleNoxazoline
[Ale
ꢀ
ꢀ
p
amido nitrogen [25,28,30,38,39]. The bond distance of AleNoxazoline
and the angle of NoxazolineeAleNsulfonamide and CmethyleAleCmethyl
[N(1)eAleN(2) ¼ 90.69(13)ꢀ and C(19)eAleC(20) ¼ 116.63(19)ꢀ]
are comparable with those found in aluminium anilidoe
Scheme 2. Preparation complex 50.

12
C.-T. Chen et al. / Journal of Organometallic Chemistry 753 (2014) 9e19
trigonal bipyramidal geometry (
s
¼ 0.73) with distorted axes of
AleNsulfonamide [N(1)eAleN(3) ¼ 91.03(9)ꢀ] are close to those dis-
ꢀ
N
pyrazoleeAleNpyrazole [N(1)eAleN(1A) ¼ 172.28(12) A]. The nitro-
cussed above for 2.
gen atoms [N(3) and N(3A)] and carbon atom [C(17)] reside equa-
torially, forming angles subtended by aluminium [N(3)eAle
N(3A) ¼ 102.78(12)ꢀ, N(3)eAleC(17) ¼ 128.61(6)ꢀ and N(3A)eAle
The geometry of chelating six-membered ring of aluminium
oxazolylesulfonamido complex 2 is almost co-planar with evi-
dence of the dihedral angle (2.8ꢀ) between planes defined by N(1)e
AleN(2)/N(1)eC(14)eC(6)eC(1)eN(2). However, the distorted
(half-chair form) six-membered ring of aluminium pyrazolyl-based
sulfonamido complexes 50 and 8 exhibit larger dihedral angles of
N(1)eAleN(2)/N(1)eC(14)eC(6)eC(1)eN(2) (39.5ꢀ) and N(1)eAle
N(2)/N(1)eC(14)eC(6)eC(1)eN(2) (41.7ꢀ), respectively. This phe-
nomenon explains more aromatic character for the chelating ring of
aluminium oxazolylesulfonamido complex than that of aluminium
pyrazolylesulfonamido complex.
C(17)
¼
128.61(6)ꢀ]. The bond length of AleNpyrazole [Ale
ꢀ
N(1) ¼ 2.0859(19) A] is longer than the five-coordinated aluminium
ꢀ
anilidoepyrazolinate [28] [2.012(3) A for AleNpyrazole] complex.
Comparing with complex 2 and the related aluminium anilidoe
oxazolinate complexes [25], the pyrazolinate group donates less
electrons to aluminium centre than the oxazolinate group. The
ꢀ
bond lengths of AleNsulfonamide [AleN(3) ¼ 1.922(2) A] and Ale
ꢀ
C
methyl [AleC(17) ¼ 1.963(4) A] and the angle of NpyrazoleeAleNsul-
[N(3)eAleN(3A) ¼ 91.03(8)ꢀ] are comparable with those
Although some aluminium complexes bearing sulfonamido
group have been reported with the bonding between aluminium
metal centre and oxygen atom of sulfonamido [Ale
fonamide
found in five-coordinated aluminium anilido-pyrazolinate [28]
[1.964(3)e1.983(3) A for AleCmethyl and 88.23(11)ꢀ for Npyrazolee
ꢀ
ꢀ
ꢀ
AleNanilido] or sulfonamido [18,19,21] [1.895(2)e1.952(2) A for Ale
Nsulfonamide and 1.949(2)e1.986(2) A for AleCalkyl] complexes.
Osulfonamide ¼ 1.854(2)e2.193(2) A] [18,19,21]. The AleOsulfonamide
ꢀ
ꢀ
bond distances for complexes demonstrated here [2.536 A and
0
ꢀ
ꢀ
ꢀ
ꢀ
ꢀ
Alternative routes can be achieved by treatment of 5 with 1 molar
equivalent of HNSO2PhMePzH in refluxing toluene or reaction of
HNSO2PhMePzH with 0.5 molar equivalent of AlMe3 in refluxing
toluene to afford the aluminium bis-pyrazolylesulfonamide com-
plex 50. The synthetic routes are shown in (Scheme 2). Compared
with complexes 1e10, there are more remarkable differences by
spectroscopic studies for 50, i.e. the more down-field aluminium-
methyl signal on 1H NMR spectrum (0.28 ppm) and the more up-
filed signal on 27Al NMR spectrum (56.7 ppm). The 27Al chemical
shift of 50 is within the expected region for five-coordinate
aluminium species in solution (ca. 20e60 ppm) [36]. Compound
50 was characterized by elemental analyses as well.
3.992 A for 2; 3.069 A and 4.255 A for 5 ; 3.249 A and 4.306 A for 8]
indicating there are no coordinated covalent bonds between
aluminium metal centre and oxygen atom of sulfonamido group.
However, the existence of Al/Osulfonamide bond interaction could
not be excluded due to the van der Walls radius between
ꢀ
aluminium and oxygen [Al/O ¼ 3.5 A].
2.2. Catalytic studies of ring-opening polymerization
Since some aluminium sulfonamido complexes [18,19,21] and
aluminium anilidoeoxazolinate [25], anilidopyrazolate [28],
b-
diketiminates [29], anilidoeiminates [30,31], amidinates [32,33] or
phosphinoeiminates [34,35] complexes have shown their catalytic
activities in ROP, structure-related aluminium sulfonamido com-
plexes 1e10 are expected to work as catalysts toward the ROP. The
similar conditions used in our previous work [24e28] were intro-
duced to examine the catalytic activities in the ROP of ε-capro-
lactone. Representative results are collected in Table 1. Under the
same condition, the aluminium complexes containing pyrazolinate
group (entries 4e7) exhibited better activities than those with
dimethyl-pyrazolinate group (entries 8e10) or oxazolinate group
(entries 1e3) in the presence of benzyl alcohol with the order of
PzH > PzMe > Oxa at 25 ꢀC with a period of 30 min in toluene. This
trend was observed under elevated temperature condition (entries
11e13) or in the absence of benzyl alcohol (entries 14e16). Upon
comparing catalytic activity with complex 4 (entry 4), complex 7
containing electron-withdrawing substituent on phenyl group of
sulfonamido species results in the inhibition of catalytic activity.
The optimized conditions were reconfirmed using complex 4 as
catalyst in dichloromethane or THF with poor conversions (entries
17e18). This might result from the competition between solvent
and monomer or initiator. The analysis of end group were
demonstrated by the 1H NMR spectra of the polymers produced
with or without the addition of benzyl alcohol (entries 12 and 15),
as shown in Figs. 4 and 5. Peaks in Fig. 4 are assignable to the
corresponding protons in the proposed structure, indicating the
metal benzyl oxide complex might form first, followed by the
monomer of the ring cleavage of acyleoxygen bond to form a metal
alkoxide intermediate, which further reacts with excess monomers
to yield polyester [24e28]. However, no end group in Fig. 5 was
found on the polymer produced without the addition of benzyl
alcohol as initial agent. These are further supported by matrix-
assisted laser desorption ionization time-of-flight (MALDI-TOF)
mass spectroscopic analysis in Figs. 6 and 7. The repeating mass is
assigned to {H[ε-caprolactone]nOBn} þ Naþ from entry 12 in Fig. 6,
and the repeating mass is assigned to [ε-caprolactone]n þ Naþ from
entry 15 in Fig. 7, which are consistent with the analysis of Figs. 4
Suitable crystals for structure determination of 8 were obtained
from tetrahydrofuran/hexane solution. The molecular structure is
depicted in Fig. 3. Complex 8 is similar to 2 but with the dimethyl-
pyrazolinate group instead of the oxazolinate group. The bond
ꢀ
distance of AleNpyrazole [AleN(3) ¼ 1.972(2) A] is slightly longer
than those found in aluminium anilidoeoxazolinate [25]
ꢀ
[1.9590(17)
A
for AleNpyrazole
]
or anilidoeimino [30,38]
ꢀ
[1.917(5)e1.963(1) A for AleNimine] complexes. The bond length
of AleNsulfonamide [AleN(3) ¼ 1.915(2) A] and the angle of Npyrazolee
ꢀ
Fig. 3. Molecular structure of complex 8. Hydrogen atoms are omitted for clarity.
ꢀ
ꢀ
Selected bond lengths (A) and bond angles ( ): AleN(1), 1.915(2); AleN(3), 1.972(2);
AleC(18), 1.952(3); AleC(19), 1.957(3); SeO(1), 1.4416(18); SeO(2), 1.4365(19); SeN(1),
1.607(2); SeC(7), 1.777(3); N(2)eN(3), 1.370(3); N(1)eC(1), 1.429(3); N(2)eC(2),
1.428(3); C(1)eC(2), 1.397(3); N(1)eAleN(3), 91.03(9); C(18)eAleC(19), 120.92(13);
N(1)eAleC(18), 115.93(11); N(1)eAleC(19), 106.92(11); N(3)eAleC(18), 110.70(11);
N(3)eAleC(19), 107.01(10); O(1)eSeO(2), 118.07(11); N(1)eSeC(7), 106.82(11).

C.-T. Chen et al. / Journal of Organometallic Chemistry 753 (2014) 9e19
13
Table 1
Polymerization of ε-caprolactone using compounds 1e12 as catalysts in toluene if not otherwise stated.a
,k
,k
b,k,l
Entry
Catalyst
[ε-CL]:[Al]:[BnOH]
T (ꢀC)
t (min)
Mn (obsd)b
Mn (calcd)c
Conv. (%)d
Yield (%)e
Mw/Mn
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
8
9
10
1
4
8
1
4
8
4
4
4
4
4
4
4
5
100:1:2
100:1:2
100:1:2
100:1:2
100:1:2
100:1:2
100:1:2
100:1:2
100:1:2
100:1:2
100:1:2
100:1:2
100:1:2
100:1:0
100:1:0
100:1:0
100:1:2
100:1:2
200:1:2
300:1:2
400:1:2
200:1:4
50:1:1
25
25
25
25
25
25
25
25
25
25
50
50
50
50
50
50
25
50
25
25
25
25
25
50
50
50
25
50
30
30
30
30
30
30
30
30
30
30
30
10
25
150
150
150
30
e
e
23
23
18
93
91
93
76
48
54
59
95
98
91
17
97
70
11
11
93
98
90
90
90
95
81
95
91
92
e
e
e
e
e
e
e
e
e
e
7800
8000
9200
6700
e
5400
4300
5400
4400
e
84
81
91
60
e
1.20
1.20
1.20
1.17
e
9
e
e
e
e
10
11
12
13
14
15
16
17g
18h
19
20
21
22
23
24
25
26i
27j
28j
e
e
e
e
12,200
6300
5300
e
5500
5700
5300
e
11,100f
8000f
e
90
77
70
e
1.30
1.13
1.11
e
21,000
31,000
e
97
68
e
1.39
1.39
e
30
e
e
e
e
105
210
450
135
240
10
10
120
60
14,700
22,800
28,900
5200
7800
7600
6100
13,000
9100
8900
10,700
16,900
92
96
88
72
84
86
46
94
89
86
1.15
1.19
1.20
1.13
1.58
1.08
1.34
1.06
1.12
1.11
20.600
5100
5100
5500
4700
5500
5200
5400
100:1:2
50:1:1
100:1:2
100:1:2
100:1:2
50
11
12
12
12
a
In 15 mL.
b
c
d
e
f
Obtained from GPC analysis times 0.56.
Calculated from [M(ε-CL) ꢂ [ε-CL]/[Al] ꢂ conversion/([BnOH]eq)] þ M(BnOH).
Obtained from 1H NMR analysis.
Isolated yield.
Calculated from (M(ε-CL) ꢂ [ε-CL]/[Al] ꢂ conversion).
g
h
i
In CH2Cl2.
In THF.
Ref. [25].
Ref. [28].
j
k
l
Mw (weight average molecular weight).
Mw (weight average molecular weight).
and 5 [41,42]. The mechanism for the formation of cyclic PCL might
be initiated by ligand and end up with trans-esterification, which is
similar to those reported in the literature [43,44]. The linear rela-
tionship between Mn and the monomer-to-initiator ([ε-CL]/[Al])
exhibited by complex 4 implies the “living” character of the poly-
merization process at 25 ꢀC (entries 4, 19e21; PDIs ¼ 1.15e1.20),
and representative results are demonstrated in Fig. 8. The
“immortal” character was examined using one, two and four
equivalents benzyl alcohol as the chain transfer agent (entries 4,
22e23). The five-coordinated aluminium bis-sulfonamido complex
50 also demonstrated catalytic activity, but with poor activity
1
1
Fig. 4. H NMR spectrum of poly(ε-caprolactone) initiated by 4 in toluene at 25 ꢀC in
Fig. 5. H NMR spectrum of poly(ε-caprolactone) initiated by 4 in toluene at 25 ꢀC in
the presence of BnOH (Table 1, entry 12).
the absence of BnOH (Table 1, entry 15).

14
C.-T. Chen et al. / Journal of Organometallic Chemistry 753 (2014) 9e19
catalytic activities (entries 4, 11e12 and 26e28). Furthermore
comparing with other structurally related aluminium complexes,
the catalytic activity of complex 4 is more active than aluminium
anilidoealdiminate [30] or aluminium anilidoeiminate [31] com-
plexes. Trials have been done by the reactions between aluminium
dimethyl complexes 1, 4 or 8 with two molar equivalent benzyl
alcohols within 5 min at room temperature using benzene-d6 as
solvent to understand the details of active species of polymeriza-
tion in situ with benzyl alcohol (Fig. S2). Although the syntheses of
aluminium alkoxide complexes were failed, the similar phenomena
were observed and consistent with our previous work [28]. Based
on the 1H NMR spectrometric studies, the active species could be
formulated as a [(BnO)2AlMe]n derivative. The activity of poly-
merization might be assessed by the determination of the mixed
compounds from the protonation of the aluminium anilidopyr-
azolate complex and benzyl alcohol [32,45].
3. Conclusions
Fig. 6. MALDI-TOF mass spectrum of poly(ε-caprolactone) initiated by 4 in toluene at
25 ꢀC in the presence of BnOH (Table 1, entry 12).
A series of oxazolinate- or pyrazolinate-based sulfonamido
ligand precursors and related aluminium complexes 1e10 have
been prepared and characterized. The molecular structures are
reported as four-coordinated aluminium dimethyl complexes (for 2
and 8) and five-coordinated aluminium monomethyl complex (for
50). All aluminium complexes were found to be active in catalyzing
the polymerization of ε-caprolactone in the presence of benzyl
alcohol with well-controlled Mn and narrow PDIs. Compounds with
pyrazolinate group seem to be more active than those with
dimethyl-pyrazolinate and oxazolinate group. Introduction of sul-
fonamido group indeed proved the enhancement of catalytic ac-
tivity for ROP of ε-caprolactone comparing with our previously
related works. Complex
4 exhibited efficient activities for
controlled polymerization of ε-caprolactone with “living” and
“immortal” characters under the optimized condition. The activity
of ROP might be assessed by the determination of the mixed
compounds from the protonation of the aluminium anilidoepyr-
azolate complex and benzyl alcohol resulting in the formation of
the ligand precursor and the [(BnO)2AlMe]n derivatives.
Fig. 7. MALDI-TOF mass spectrum of poly(ε-caprolactone) initiated by 4 in toluene at
25 ꢀC in the absence of BnOH (Table 1, entry 15).
comparing with 5 at 50 ꢀC within 10 min (entries 24e25). This
might result from the bulkier environment around five-
coordinated aluminium centre and the modification of Lewis
acidity of metal centre caused by the ligands. Optimized conditions
were introduced to examine the catalytic activities of structure-
related aluminium anilidoeoxazolinate complex (11) and anilido-
pyrazolinate complexes (12) (entries 26e28), as shown in
(Scheme 3). Based on the experimental results, introduction of
sulfonamido group into these two systems can enhance the
4. Experimental
4.1. General conditions
All manipulations were carried out under an atmosphere of
dinitrogen using standard Schlenk-line or drybox techniques. Sol-
vents were refluxed over the appropriate drying agent and distilled
prior to use. Deuterated solvents were dried over molecular sieves.
1H and 13C{1H} NMR spectra were recorded either on Varian
Mercury-400 (400 MHz) or Varian Inova-600 (600 MHz) spec-
trometers in chloroform-d at ambient temperature unless stated
otherwise and referenced internally to the residual solvent peak
and reported as parts per million relative to tetramethylsilane. 27Al
{1H} NMR spectra were referenced externally using Al(acac)3 at
Fig. 8. Polymerization of ε-caprolactone initiated by 4 in toluene at 25 ꢀC in the
presence of BnOH (Table 1, entries 4, 19e21).
Scheme 3. Molecular structures of complexes 11 and 12.

C.-T. Chen et al. / Journal of Organometallic Chemistry 753 (2014) 9e19
15
d
¼ 0 ppm. Elemental analyses were performed by an Elementar
obtained (1.04 g, 56.0%). Anal. Calc. for C20H24N2O3S: C, 64.49; H,
6.49; N, 7.52. Found: C, 64.48; H, 6.71; N, 7.25. 1H NMR (400 MHz,
Vario ELIV instrument. Matrix-assisted laser desorption ionization
time-of-flight (MALDI-TOF) mass spectrometric studies of poly(ε-
caprolactone) were performed by using Bruker Autoflex III TOF/TOF
spectrometer. The Gel Permeation Chromatography (GPC) mea-
surements were performed in THF at 35 ꢀC with a Waters 1515
isocratic High Performance Liquid Chromatography (HPLC) pump, a
Waters 2414 refractive index detector, and Waters styragel column
(HR4E). Molecular weights and molecular weight distributions
were calculated using polystyrene as standard.
p-Toluenesulfonyl chloride (Acros), benzenesulfonyl chloride
(Alfa Aesar), 2-mesitylenesulfonyl chloride (Alfa Aesar), 4-
fluorobenzenesulfonyl chloride (Acros), 9-anthracenmethanol
(Acros) and trimethylaluminium (1.0 M in heptane, Aldrich) were
used as supplied. Trimethylamine (TMEDIA), benzyl alcohol
(TEDIA) and ε-caprolactone (Acros) were dried over CaH2 and
distilled before use. 2-(4,4-dimethyl-4,5-dihydrooxazo-2-yl)-phe-
nylamine [46], 1-(2-aminophenyl)pyrazole [47] and 1-(3,5-
dimethyl-2-aminophenyl)pyrazole [48] were prepared by the
modified literature’s methods.
CDCl3):
d (ppm) 12.56 (br, 1H, eNH), 7.75 (m, 1H, C6H5), 7.25e7.33
(overlap, 2H, C6H5), 6.90e6.96 (overlap, 3H, C6H5), 4.07 (s, 2H, Oxa-
CH2), 2.71 (s, 6H, o-CH3ePh), 2.24 (s, 3H, p-CH3ePh), 1.41 (s, 6H,
Oxa-CH3). 13C NMR (100 MHz, CDCl3):
d (ppm) 161.7, 142.3, 139.3,
139.2, 133.8, 112.3, 67.9 (CipsoeC6H5), 132.2, 131.9, 129.3, 121.2, 115.6
(CHeC6H5), 77.9 (Oxa-CH2), 28.3 (Oxa-CH3), 22.8 (o-CH3ePh), 20.8
(p-CH3ePh).
4.5. HNSO2PhHPzH
To a flask containing 1-(2-aminophenyl)pyrazole (0.796 g,
5.0 mmol) in 15 mL dichloromethane, a solution of benzenesulfonyl
chloride (0.970 g, 5.5 mmol) in 15 mL dichloromethane was added
at room temperature. To this mixture solution, NEt3 (0.765 mL,
5.5 mmol) was added via syringe at 0 ꢀC. After one hour of stirring,
all the volatiles were pumped off and the residue was extracted
with toluene 5 mL ꢂ 3. Crude product was purified by column
chromatography (hexane/ethyl acetate 3:1). The second band was
collected to afford white solid (0.958 g, 64.0%). The third band was
collected to afford di-substituted side product, PzHN(SO2PhH)2, as
white solid (0.375 g, 17.0%). Data for HNSO2PhHPzH: Anal. Calc. for
4.2. HNSO2PhHOxa
To a flask containing 2-(4,4-dimethy-4,5-dihydro-oxazo-2-yl)-
phenylamine (0.950 g, 5.0 mmol) in 15 mL dichloromethane, a
solution of benzenesulfonyl chloride (0.970 g, 5.5 mmol) in 15 mL
dichloromethane was added at room temperature. To this reaction
mixture, NEt3 (0.765 mL, 5.5 mmol) was added via syringe at 0 ꢀC.
After one hour of stirring, all the volatiles were pumped off. The
residue was dissolved in ethyl acetate and washed with deionized
water. Collect organic layer to afford crude product. Crude product
was washed with methanol (5 mL ꢂ 3) to yield white solid (1.29 g,
78%). Anal. Calc. for C17H18N2O3S: C, 61.80; H, 5.49; N, 8.48. Found:
C
15H13N3O2S: C, 60.18; H, 4.38; N, 14.04. Found: C, 59.74; H, 4.26; N,
13.64. 1H NMR (400 MHz, CDCl3):
d
(ppm) 10.09 (br, 1H, eNH), 7.77
(dd, J ¼ 8.0 & 1.4 Hz, 1H, C6H5), 7.72 (d, J ¼ 2.0 Hz, 1H, C6H5), 7.38 (m,
3H, C6H5), 7.27e7.33 (overlap, 2H, C6H5), 7.12e7.23 (overlap, 4H,
C6H5), 6.33 (m, 1H, C6H5). 13C NMR (100 MHz, CDCl3):
d (ppm) 138.7,
131.4, 129.8 (CipsoeC6H5), 141.0, 132.3, 129.3, 128.6, 127.8, 126.4,
126.1, 125.8, 121.7, 107.3 (CHeC6H5). Data for PzHN(SO2PhH)2: Anal.
Calc. for C21H17N3O4S2: C, 57.39; H, 3.90; N, 9.56. Found: C, 57.20; H,
3.69; N, 9.15. NMR (400 MHz, CDCl3):
d (ppm) 8.17 (m, 1H, C6H5),
7.84e7.87 (overlap, 4H, C6H5), 7.62e7.69 (overlap, 3H, C6H5), 7.58
(td, J ¼ 7.8 & 1.2 Hz, 1H, C6H5), 7.47e7.51 (overlap, 5H, C6H5), 7.32
(m, 1H, C6H5), 6.95 (dd, J ¼ 8.0 & 1.4 Hz, 1H, C6H5), 6.10 (t, J ¼ 2.0 Hz,
C, 61.88; H, 5.56; N, 8.35. 1H NMR (400 MHz, CDCl3):
d (ppm) 12.33
(br,1H, eNH), 7.83 (m, 2H, C6H5), 7.70e7.75 (overlap, 2H, C6H5), 7.47
(m, 1H, C6H5), 7.34e7.40 (overlap, 3H, C6H5), 7.02 (m, 1H, C6H5), 4.01
(s, 2H, Oxa-CH2), 1.39 (s, 6H, Oxa-CH3). 13C NMR (100 MHz, CDCl3):
1H, C6H5). 13C NMR (100 MHz, CDCl3):
d (ppm) 140.7, 138.7, 127.7
(CipsoeC6H5), 141.2, 134.0, 132.6, 131.5, 131.4, 129.1, 128.7, 128.0,
127.8, 107.4 (CHeC6H5) [49,50].
d
(ppm) 161.5, 139.8, 138.9, 114.3, 67.8 (CipsoeC6H5), 132.6, 132.2,
129.1, 128.7, 127.0, 122.7, 118.8 (CHeC6H5), 77.9 (s, Oxa-CH2), 28.3 (s,
Oxa-CH3).
4.6. HNSO2PhMePzH
4.3. HNSO2PhMeOxa
To a flask containing 1-(2-aminophenyl)pyrazole (0.796 g,
5.0 mmol) and toluenesulfonyl chloride (1.05 g, 5.5 mmol), 30 mL
dichloromethane were added at room temperature. To this reaction
mixture, NEt3 (0.765 mL, 5.5 mmol) was added via syringe at 0 ꢀC.
After one hour of stirring, all the volatiles were pumped off. The
residue was extracted with toluene (5 mL ꢂ 3). Crude product was
purified by column chromatography (hexane/ethyl acetate 3:1).
The second band was collected to afford pale-white solid (1.05 g,
67.0%). The third band was collected to afford di-substituted side
product, PzHN(SO2PhMe)2, as white solid (0.165 g, 7.0%). Data for
HNSO2PhMePzH: Anal. Calc. for C16H15N3O2S: C, 61.32; H, 4.82; N,
13.41. Found: C, 61.60; H, 5.08; N, 13.50. 1H NMR (400 MHz, CDCl3):
To a flask containing 2-(4,4-dimethy-4,5-dihydro-oxazo-2-yl)-
phenylamine (0.95 g, 5.0 mmol) and toluenesulfonyl chloride
(1.05 g, 5.5 mmol), 30 mL dichloromethane were added at room
temperature. To this reaction mixture, NEt3 (0.765 mL, 5.5 mmol)
was added via syringe at 0 ꢀC. After two hour of stirring, all the
volatiles were pumped off. The residue was dissolved in ethyl ac-
etate and washed with deionized water. Collect organic layer to
afford crude product. Crude product was washed with methanol
(5 mL ꢂ 3) to afford white solid (1.24 g, 72.0%). Anal. Calc. for
C
18H20N2O3S: C, 62.77; H, 5.85; N, 8.13. Found: C, 62.53; H, 5.81; N,
8.13. 1H NMR (400 MHz, CDCl3):
d
(ppm) 12.29 (br, 1H, eNH), 7.70e
d (ppm) 10.04 (br, 1H, eNH), 7.73e7.77 (overlap, 2H, C6H5), 7.26e
7.74 (overlap, 4H, C6H5), 7.35 (m, 1H, C6H5), 7.17 (m, 2H, C6H5), 7.01
(m, 1H, C6H5), 4.02 (s, 2H, Oxa-CH2), 2.34 (s, 3H, eCH3), 1.40 (s, 6H,
7.34 (overlap, 4H, C6H5), 7.14e7.20 (overlap, 2H, C6H5), 7.01 (d,
J ¼ 8.4 Hz, 2H, C6H5), 6.36 (m, 1H, C6H5), 2.30 (s, 3H, eCH3). 13C NMR
Oxa-CH3). 13C NMR (100 MHz, CDCl3):
d
(ppm) 161.5, 143.2, 138.8,
(100 MHz, CDCl3): d (ppm) 143.1, 135.7, 131.0, 129.8 (CipsoeC6H5),
136.6, 113.9, 67.6 (CipsoeC6H5), 131.9, 129.1, 129.0, 126.7, 122.4, 118.2
(CHeC6H5), 77.6 (s, Oxa-CH2), 28.1 (s, Oxa-CH3), 21.1 (s, eCH3).
140.8, 129.2, 129.1, 127.6, 126.3, 125.8, 125.2, 121.6, 107.1 (CHeC6H5),
21.2 (eCH3). Data for PzHN(SO2PhMe)2: Anal. Calc. for
C
23H21N3O4S2: C, 59.08; H, 4.53; N, 8.99. Found: C, 59.05; H, 4.73; N,
4.4. HNSO2PhTriMeOxa
8.40. 1H NMR (400 MHz, CDCl3):
d
(ppm) 8.20 (m, 1H, C6H5), 7.71 (d,
J ¼ 8.4 Hz, 4H, C6H5), 7.67 (dd, J ¼ 8.0 & 1.6 Hz, 1H, C6H5), 7.52e7.58
(overlap, 2H, C6H5), 7.31 (m, 2H, C6H5), 7.26 (dd, J ¼ 8.0 & 0.4 Hz, 4H,
C6H5), 6.96 (d, J ¼ 8.4 Hz, 1H, C6H5), 6.13 (m, 1H, C6H5), 2.46 (s, 6H, e
The procedure for the preparation of HNSO2PhTriMeOxa was
similar to that used for HNSO2PhMeOxa but with 2-
mesitylenesulfonyl chloride (1.20 g, 5.5 mmol). A white solid was
CH3). 13C NMR (100 MHz, CDCl3):
d (ppm) 145.1, 140.7, 135.9, 131.3

16
C.-T. Chen et al. / Journal of Organometallic Chemistry 753 (2014) 9e19
(CipsoeC6H5), 141.0, 132.6, 131.5, 129.3, 129.2, 127.9, 127.7, 107.3 (CHe
C6H5), 21.6 (eCH3) [51].
4.10. HNSO2PhHPzMe
The procedure for the preparation of HNSO2PhHPzMe was
similar to that used for HNSO2PhHPzH but with 2-(3,5-
dimethylpyrazol-1-yl)phenylamine (0.94 g, 5.0 mmol) and benze-
nesulfonyl chloride (0.970 g, 5.5 mmol). Crude product was purified
by column chromatography (hexane/ethyl acetate 2:1). The second
band was collected to afford pink solid (0.98 g, 60.0%). Anal. Calc. for
4.7. HNSO2PhTriMePzH
The procedure for the preparation of HNSO2PhTriMePzH was
similar to that used for HNSO2PhMePzH but with 2-
mesitylenesulfonyl chloride (1.20 g, 5.5 mmol) and 20 mL
dichloromethane. The second band was collected to afford white
solid (0.96 g, 56.0%). Anal. Calc. for C18H19N3O2S: C, 63.32; H, 5.61;
N, 12.31. Found: C, 63.18; H, 5.49; N, 12.53. 1H NMR (400 MHz,
C
17H17N3O2S: C, 62.36; H, 5.23; N, 12.83. Found: C, 62.34; H, 5.25; N,
12.92. 1H NMR (400 MHz, CDCl3):
d
(ppm) 8.99 (br, 1H, eNH), 7.79
(dd, J ¼ 8.0 & 1.6 Hz, 1H, C6H5), 7.33e7.46 (overlap, 4H, C6H5), 7.25e
7.30 (overlap, 2H, C6H5), 7.19 (td, J ¼ 8.4 & 1.3 Hz,1H, C6H5), 7.01 (dd,
J ¼ 8.0 & 1.2 Hz, 1H, C6H5), 5.86 (s, 1H, C6H5), 2.31 (s, 3H, eCH3), 1.68
CDCl3):
d
(ppm) 9.97 (br,1H, eNH), 7.75 (d, J ¼ 1.2 Hz,1H, C6H5), 7.55
(dd, J ¼ 8.0 & 1.2 Hz, 1H, C6H5), 7.51 (dd, J ¼ 2.4 & 0.4 Hz, 1H, C6H5),
7.19e7.26 (overlap, 2H, C6H5), 7.13 (m, 1H, C6H5), 6.79 (br, 2H, C6H5),
6.40 (m, 1H, C6H5), 2.41 (s, 6H, o-CH3ePh), 2.22 (s, 3H, p-CH3ePh).
(s, 3H, eCH3). 13C NMR (100 MHz, CDCl3):
d (ppm) 150.2, 140.9,
139.1, 131.6, 131.1 (CipsoeC6H5), 132.4, 128.6, 128.3, 126.4, 126.0,
125.6, 124.9, 106.9 (CHeC6H5), 13.4 (eCH3), 11.8 (eCH3).
13C NMR (100 MHz, CDCl3):
d (ppm) 142.1, 138.8, 133.4, 130.2, 130.1
(CipsoeC6H5), 141.0, 132.6, 131.5, 129.3, 129.2, 127.9, 127.7, 107.3 (CHe
C6H5), 21.6 (eCH3).
4.11. HNSO2PhMePzMe
The procedure for the preparation of HNSO2PhMePzMe was
similar to that used for HNSO2PhMePzH but with 2-(3,5-
dimethylpyrazol-1-yl)phenylamine (0.94 g, 5.0 mmol) and tolue-
nesulfonyl chloride (1.05 g, 5.5 mmol). Crude product was purified
by column chromatography (hexane/ethyl acetate 5:1). The second
band was collected to afford pink solid (1.02 g, 60.0%). Anal. Calc. for
4.8. HNSO2PhFPzH
The procedure for the preparation of HNSO2PhFPzH was similar
to that used for HNSO2PhMePzH but with 4-fluorobenzene-sulfo-
nyl chloride (2.92 g, 15 mmol). Crude product was purified by
column chromatography (hexane/ethyl acetate 5:1). The second
band was collected to afford orange-red oil. The oil was triturated
with ethanol to afford orange solid (1.33 g, 28.0%). The third band
was collected to afford di-substituted side product,
PzHN(SO2PhF)2, as white solid (0.71 g, 10.0%). Data for
HNSO2PhFPzH: Anal. Calc. for C15H12FN3O2S: C, 56.77; H, 3.81; N,
13.24. Found: C, 56.80; H, 3.88; N, 12.96. 1H NMR (400 MHz,
C
18H19N3O2S: C, 63.32; H, 5.61; N, 12.31. Found: C, 63.45; H, 6.01; N,
12.30. 1H NMR (400 MHz, CDCl3):
d
(ppm) 8.92 (br, 1H, eNH), 7.34
(dd, J ¼ 8.0 & 1.0 Hz, 1H, C6H5), 7.34 (m, 1H, C6H5), 7.27 (m, 2H,
C6H5), 7.17 (m, 1H, C6H5), 7.07 (d, J ¼ 8.0 Hz, 2H, C6H5), 6.99 (dd,
J ¼ 8.0 & 1.4 Hz, 1H, C6H5), 5.88 (s, 1H, C6H5), 2.33 (s, 3H, eCH3), 2.31
(s, 3H, eCH3), 1.70 (s, 3H, eCH3). 13C NMR (100 MHz, CDCl3):
d
(ppm) 150.2, 143.2, 140.8, 136.2, 131.8, 131.0 (CipsoeC6H5), 129.2,
CDCl3):
d (ppm) 10.10 (br, 1H, eNH), 7.74e7.79 (overlap, 2H, C6H5),
128.4, 126.5, 125.7, 125.4, 125.0, 106.9 (CHeC6H5), 21.3 (eCH3), 13.4
(eCH3), 11.6 (eCH3).
7.32e7.40 (overlap, 4H, C6H5), 7.17e7.27 (overlap, 2H, C6H5), 6.89
(t, J ¼ 8.4 Hz, 2H, C6H5), 6.37 (br, 1H, C6H5). 13C NMR (100 MHz,
4.12. HNSO2PhTriMePzMe
CDCl3):
d (ppm) 166.0, 163.4, 134.6, 131.4 (CipsoeC6H5), 141.0, 129.2,
129.1, 129.0, 127.9, 126.4, 126.1, 121.6, 115.9, 115.7, 107.3 (CHeC6H5).
Data for PzHN(SO2PhF)2: Anal. Calc. for C21H15F2N3O4S2: C, 53.05;
H, 3.18; N, 8.84. Found: C, 53.51; H, 3.34; N, 9.07. 1H NMR
The procedure for the preparation of HNSO2PhTriMePzMe was
similar to that used for HNSO2PhTriMePzH but with 2-(3,5-
dimethylpyrazol-1-yl)phenylamine (0.94 g, 5.0 mmol). Crude
product was purified by column chromatography (hexane/ethyl
acetate 5:1). The second band was collected to afford pale-yellow
solid (0.83 g, 45.0%). Anal. Calc. for C20H23N3O2S: C, 65.01; H,
6.27; N, 11.37. Found: C, 65.16; H, 6.58; N, 11.57. 1H NMR (400 MHz,
(400 MHz, CDCl3):
d (ppm) 8.12 (m, 1H, C6H5), 7.87e7.90 (overlap,
4H, C6H5), 7.57e7.66 (overlap, 2H, C6H5), 7.51 (d, J ¼ 1.6 Hz, 1H,
C6H5), 7.35 (m, 1H, C6H5), 7.14e7.18 (overlap, 4H, C6H5), 6.97 (dd,
J ¼ 8.0 & 1.6 Hz, 1H, C6H5), 6.16 (m, 1H, C6H5). 13C NMR (100 MHz,
CDCl3):
d (ppm) 167.2, 164.6, 140.6, 134.6, 127.7 (CipsoeC6H5), 141.3,
132.5, 132.3, 132.2, 131.7, 131.4, 128.2, 128.0, 116.2, 116.0, 107.5 (CHe
C6H5).
CDCl3):
d
(ppm) 8.68 (br, 1H, eNH), 7.73 (dd, J ¼ 8.0 & 1.2 Hz, 1H,
C6H5), 7.32 (m, 1H, C6H5), 7.16 (td, J ¼ 7.8 & 1.3 Hz, 1H, C6H5), 7.03
(dd, J ¼ 8.0 & 1.2 Hz, 1H, C6H5), 6.75 (br, 2H, C6H5), 5.89 (br, 1H,
C6H5), 2.28 (s, 6H, o-CH3ePh), 2.27 (s, 3H, eCH3), 2.22 (s, 3H, eCH3),
4.9. PzHN(SO2PhF)2
1.73 (s, 3H, eCH3). 13C NMR (100 MHz, CDCl3):
d (ppm) 150.5, 142.0,
To a flask containing 1-(2-aminophenyl)pyrazole (0.159 g,
1.0 mmol) and 4-fluorobenzene-sulfonyl chloride (0.428 g,
1.0 mmol), 30 mL THF were added at room temperature. To this
reaction mixture, NEt3 (0.31 mL, 2.2 mmol) was added via syringe
at 0 ꢀC. The reaction mixture was warmed up to 50 ꢀC. After one
hour of stirring, all the volatiles were pumped off. The residue was
extracted with toluene (5 mL ꢂ 3). Crude product was purified by
column chromatography (hexane/ethyl acetate 3:1). The second
band was collected to afford white solid (0.357 g, 75.0%). 1H NMR
141.0, 139.0, 133.9, 132.0, 131.3 (CipsoeC6H5), 131.6, 128.3, 125.7,
125.5, 125.3, 109.6 (CHeC6H5), 22.8 (eCH3), 20.7 (eCH3), 13.4 (e
CH3), 11.4 (eCH3).
4.13. (NSO2PhHOxa)AlMe2 (1)
To a flask containing HNSO2PhHOxa (0.33 g, 1.0 mmol) and
15 mL THF, 1.1 mL AlMe3 (1.0 M in heptane, 1.1 mmol) was added at
0
ꢀC. The reaction mixture was allowed to warm to room temper-
(400 MHz, CDCl3):
d
(ppm) 8.12 (m, 1H, C6H5), 7.87e7.90 (overlap,
ature and reacted for one hour. All the volatiles were removed
under reduced pressure to afford pale-yellow solid. The crude
product was washed with 5 mL hexane to afford white solid
(0.228 g, 57%). Anal. Calc. for C19H23N2O3SAl: C, 59.05; H, 6.00; N,
7.25. Found: C, 59.38; H, 5.92; N, 6.70. 1H NMR (600 MHz, CDCl3):
4H, C6H5), 7.57e7.66 (overlap, 2H, C6H5), 7.51 (d, J ¼ 1.6 Hz, 1H,
C6H5), 7.35 (m, 1H, C6H5), 7.14e7.18 (overlap, 4H, C6H5), 6.97 (dd,
J ¼ 8.0 & 1.6 Hz, 1H, C6H5), 6.16 (m, 1H, C6H5). 13C NMR (100 MHz,
CDCl3):
d (ppm) 167.2, 164.6, 140.6, 134.6, 127.7 (CipsoeC6H5), 141.3,
132.5, 132.3, 132.2, 131.7, 131.4, 128.2, 128.0, 116.2, 116.0, 107.5 (CHe
C6H5).
d
(ppm) 8.00 (d, J ¼ 7.8 Hz, 2H, C6H5), 7.88 (dd, J ¼ 7.8 & 1.5 Hz, 1H,
C6H5), 7.53 (t, J ¼ 7.2 Hz, 1H, C6H5), 7.47 (t, J ¼ 7.5 Hz, 2H, C6H5), 7.40

C.-T. Chen et al. / Journal of Organometallic Chemistry 753 (2014) 9e19
17
(d, J ¼ 8.4 Hz, 1H, C6H5), 7.29 (m, 1H, C6H5), 6.88 (t, J ¼ 7.5 Hz, 1H,
C6H5), 4.25 (s, 2H, Oxa-CH2), 1.59 (s, 6H, Oxa-CH3), e0.47 (s, 6H, Ale
CH3). 13C NMR (150 MHz, CDCl3):
(ppm) 167.1, 145.1, 140.5, 110.9,
4.18. (NSO2PhMePzH)2AlMe (50)
d
There are two methods to prepare as following: (I) To a flask
containing HSO2PhMePzH (0.627 g, 2.0 mmol) and 15 mL dry
toluene, AlMe3 (1.10 mL, 1.10 mmol) were added at 0 ꢀC under ni-
trogen. The reaction mixture was allowed to warm to room tem-
perature and reacted in oil bath at 80 ꢀC. After 12 h of stirring, the
white suspension was filtered and the filtrate was pumped to
dryness to afford white solid (0.533 g, 80%). (II) To a flask containing
5 (0.369 g, 1.0 mmol) in toluene, a toluene solution of HNSO2Ph-
MePzH (0.313 g, 1.0 mmol) was added. The reaction mixture was
heated in oil bath at 80 ꢀC. After 12 h of stirring, the white sus-
pension was filtered and the filtrate was pumped to dryness to
afford white solid (0.505 g, 76%). Anal. Calc. for C33H31AlN6O4S2: C,
59.45; H, 4.69; N, 12.60. Found: C, 58.88; H, 4.54; N, 12.86. 1H NMR
68.2 (CipsoeC6H5), 135.2, 132.5, 131.0, 129.0, 127.8, 120.3, 118.8 (CHe
C6H5), 79.2 (Oxa-CH2), 27.0 (Oxa-CH3), e5.1 (AleCH3). 27Al NMR
(156 MHz):
d
103.8 (Dn1/2 ¼ 6203.7).
4.14. (NOxaSO2PhMe)AlMe2 (2)
The procedure for the preparation of 2 was similar to that used
for 1 but with HNOxaSO2PhMe (0.344 g, 1.0 mmol). A white solid
was obtained (0.272 g, 68.0%). Anal. Calc. for C20H25N2O3SAl: C,
59.98; H, 6.29; N, 7.00. Found: C, 60.14; H, 6.33; N, 6.92. 1H NMR
(600 MHz, CDCl3):
d (ppm) 7.87e7.89 (overlap, 3H, C6H5), 7.39 (d,
J ¼ 9.0 Hz, 1H, C6H5), 7.26e7.30 (overlap, 3H, C6H5), 6.87 (t,
J ¼ 7.5 Hz, 1H, C6H5), 4.25 (s, 2H, Oxa-CH2), 2.38 (s, 3H, CH3), 1.57 (s,
6H, Oxa-CH3), e0.47 (s, 6H, AleCH3). 13C NMR (150 MHz, CDCl3):
(600 MHz, CDCl3):
d
(ppm) 8.22 (d, J ¼ 1.8 Hz, 2H, C6H5), 7.36 (d,
J ¼ 1.8 Hz, 2H, C6H5), 7.08 (dd, J ¼ 8.4 & 1.5 Hz, 2H, C6H5), 6.97e7.00
(overlap, 6H, C6H5), 6.80 (d, J ¼ 8.4 Hz, 4H, C6H5), 6.72 (m, 2H, C6H5),
6.66 (dd, J ¼ 8.4 & 1.2 Hz, 2H, C6H5), 6.43 (t, J ¼ 2.4 Hz, 2H, C6H5),
2.20 (s, 6H, eCH3), 0.28 (s, 3H, AleCH3). 13C NMR (150 MHz, CDCl3):
d
(ppm) 167.1, 145.0, 143.3, 137.3, 110.8, 68.1 (CipsoeC6H5), 135.1,
130.9, 129.6, 127.8, 120.2, 118.5 (CHeC6H5), 79.1 (Oxa-CH2), 26.9
(Oxa-CH3), 21.5 (eCH3), e5.1 (AleCH3). 27Al NMR (156 MHz):
133.5
Dn1/2 ¼ 7273.5).
d
(
d (ppm) 141.1, 138.9, 133.2, 132.2 (CipsoeC6H5), 141.3, 129.8, 129.1,
128.5, 127.9, 125.7, 124.9, 120.0, 106.8 (CHeC6H5), 21.2 (eCH3), e5.2
4.15. (NOxaSO2PhTriMe)AlMe2 (3)
(AleCH3). 27Al NMR (156 MHz):
4.19. (NPzHSO2PhTriMe)AlMe2 (6)
d
56.7 (Dn1/2 ¼ 5462.2).
The procedure for the preparation of 3 was similar to that used
for 1 but with HNOxaSO2PhTriMe (0.372 g, 1.0 mmol). A white solid
was obtained (0.257 g, 60.0%). Anal. Calc. for C22H29N2O3SAl: C,
61.66; H, 6.82; N, 6.54. Found: C, 61.50; H, 7.05; N, 6.29. 1H NMR
The procedure for the preparation of 6 was similar to that used
for 1 but with HNPzHSO2PhTriMe (0.41 g, 1.0 mmol). A white solid
was obtained (0.258 g, 65.0%). Anal. Calc. for C20H24N3O2SAl: C,
60.44; H, 6.09; N, 10.57. Found: C, 60.09; H, 6.30; N, 11.02. 1H NMR
(400 MHz, CDCl3):
d (ppm) 7.89 (m, 1H, C6H5), 7.27 (m, 1H, C6H5),
7.15 (dd, J ¼ 8.4 & 0.6 Hz, 1H, C6H5), 6.88e6.92 (overlap, 3H, C6H5),
4.28 (s, 2H, Oxa-CH2), 2.64 (s, 6H, o-CH3ePh), 2.27 (s, 3H, p-CH3e
Ph), 1.59 (s, 6H, Oxa-CH3), e0.52 (s, 6H, AleCH3). 13C NMR
(600 MHz, CDCl3):
d
(ppm) 8.05 (d, J ¼ 3.0 Hz, 1H, C6H5), 7.95 (d,
J ¼ 2.4 Hz, 1H, C6H5), 7.38 (dd, J ¼ 8.4 & 1.2 Hz, 1H, C6H5), 7.33 (dd,
J ¼ 8.4 & 1.5 Hz, 1H, C6H5), 7.20 (td, J ¼ 7.8 & 1.6 Hz, 1H, C6H5), 7.10
(m,1H, C6H5), 6.85 (s, 2H, C6H5), 6.70 (t, J ¼ 2.4 Hz,1H, C6H5), 2.51 (s,
(100 MHz, CDCl3):
d (ppm) 167.2, 145.8, 135.1, 132.0, 130.9, 110.7,
68.0 (CipsoeC6H5), 141.8, 138.4, 135.9, 120.2, 118.7 (CHeC6H5), 79.4
(Oxa-CH2), 26.9 (Oxa-CH3), 22.9 (o-CH3ePh), 20.8 (p-CH3ePh), e5.3
6H, o-CH3ePh), 2.25 (s, 3H, p-CH3ePh), e0.65 (s, 6H, AleCH3). 13
C
(AleCH3). 27Al NMR (156 MHz):
d
122.8 (Dn1/2 ¼ 10349.8).
NMR (150 MHz, CDCl3): d (ppm) 141.5, 138.9, 135.7, 134.5, 129.1
(CipsoeC6H5), 140.6, 131.7, 131.4, 129.0, 124.5, 123.8, 121.4, 108.4
4.16. (NPzHSO2PhH)AlMe2 (4)
(CHeC6H5), 22.7 (o-CH3ePh), 20.7 (p-CH3ePh), e8.8 (AleCH3). 27Al
NMR (156 MHz):
d
134.9 (Dn1/2 ¼ 7256.9).
The procedure for the preparation of 4 was similar to that used
for 1 but with HNPzHSO2PhH (0.299 g, 1.0 mmol). A white solid was
obtained (0.313 g, 88.0%). Anal. Calc. for C17H18N3O2SAl: C, 57.45; H,
5.11; N, 11.82. Found: C, 57.74; H, 5.33; N, 11.39. 1H NMR (600 MHz,
4.20. (NPzHSO2PhF)AlMe2 (7)
The procedure for the preparation of 7 was similar to that used
for 1 but with HNPzHSO2PhF (0.317 g, 1.0 mmol). A white solid was
obtained (0.224 g, 60.0%). Anal. Calc. for C17H17FN3O2SAl: C, 54.68;
H, 4.59; N, 11.25. Found: C, 54.28; H, 4.90; N, 11.08. 1H NMR
CDCl3):
d
(ppm) 7.88 (d, J ¼ 3.0 Hz, 1H, C6H5), 7.85 (d, J ¼ 1.8 Hz, 1H,
C6H5), 7.76 (d, J ¼ 8.4 Hz,1H, C6H5), 7.62 (d, J ¼ 7.8 Hz, 2H, C6H5), 7.38
(t, J ¼ 7.2 Hz, 1H, C6H5), 7.26e7.31 (overlap, 4H, C6H5), 7.11 (t,
J ¼ 7.5 Hz, 1H, C6H5), 6.58 (t, J ¼ 1.6 Hz, 1H, C6H5), e0.61 (s, 6H, Ale
(400 MHz, CDCl3):
d
(ppm) 7.89 (m, 1H, C6H5), 7.79 (dd, J ¼ 8.4 &
CH3). 13C NMR (150 MHz, CDCl3):
d
(ppm) 133.1, 129.0, 128.7 (Cipsoe
1.2 Hz, 2H, C6H5), 7.63e7.67 (overlap, 2H, C6H5), 7.29e7.35 (overlap,
2H, C6H5), 7.16 (m, 1H, C6H5), 6.97 (m, 2H, C6H5), 6.63 (t, J ¼ 2.4 Hz,
1H, C6H5), e0.62 (s, 6H, AleCH3). 13C NMR (100 MHz, CDCl3):
C6H5), 140.7,131.9, 130.9,128.6,126.4,125.8,124.1,120.6,108.3 (CHe
C6H5), e8.8 (AleCH3). 27Al NMR (156 MHz):
d
111.6 (Dn1/2 ¼ 8593.2).
d
(ppm) 165.7, 163.2 (CipsoeC6H5), 137.1, 133.2 (JCeF ¼ 12.4 Hz), 140.8,
4.17. (NPzHSO2PhMe)AlMe2 (5)
130.8, 129.28, 129.26, 129.2, 126.2, 124.3, 120.7, 115.9, 115.7, 108.3
(CHeC6H5), e8.9 (AleCH3). 27Al NMR (156 MHz):
d 127.0 (Dn1/
The procedure for the preparation of 5 was similar to that used
for 1 but with HNPzHSO2PhMe (0.313 g, 1.0 mmol). A white solid was
obtained (0.258 g, 70.0%). Anal. Calc. for C18H20N3O2SAl: C, 58.52; H,
5.46; N, 11.37. Found: C, 58.71; H, 5.46; N, 10.97. 1H NMR (600 MHz,
¼ 10418.0).
2
4.21. (NPzMeSO2PhH)AlMe2 (8)
CDCl3):
d
(ppm) 7.96 (d, J ¼ 1.8 Hz, 1H, C6H5), 7.87 (d, J ¼ 1.8 Hz, 1H,
The procedure for the preparation of 8 was similar to that used
for 1 but with HNPzMeSO2PhH (0.327 g,1.0 mmol). A white solid was
obtained (0.268 g, 70.0%). Anal. Calc. for C19H22N3O2SAl: C, 59.51; H,
5.78; N, 10.96. Found: C, 59.81; H, 6.16; N, 10.55. 1H NMR (600 MHz,
C6H5), 7.71 (d, J ¼ 7.8 Hz,1H, C6H5), 7.58 (d, J ¼ 7.8 Hz, 2H, C6H5), 7.32
(d, J ¼ 7.8 Hz, 1H, C6H5), 7.23 (t, J ¼ 7.5 Hz, 1H, C6H5), 7.11 (d,
J ¼ 8.4 Hz, 2H, C6H5), 7.07 (t, J ¼ 7.5 Hz, 1H, C6H5), 6.61 (br, 1H, C6H5),
2.31 (s, 3H, eCH3), e0.61 (s, 6H, AleCH3). 13C NMR (150 MHz,
CDCl3):
129.4, 128.9, 126.8, 124.5, 123.5, 120.5, 108.2 (CHeC6H5), 21.3 (e
CH3), e8.4 (AleCH3). 27Al NMR (156 MHz):
106.6 (Dn1/2 ¼ 102.31).
CDCl3):
d
(ppm) 7.87 (dd, J ¼ 7.8 & 1.2 Hz, 1H, C6H5), 7.43 (td, J ¼ 8.1
d
(ppm) 142.9, 137.5, 133.2, 128.0 (CipsoeC6H5), 140.9, 130.7,
& 1.4 Hz, 1H, C6H5), 7.39 (m, 2H, C6H5), 7.29 (t, J ¼ 7.5 Hz, 1H, C6H5),
7.16e7.22 (overlap, 3H, C6H5), 6.96 (dd, J ¼ 7.8 & 1.2 Hz, 1H, C6H5),
5.96 (s,1H, C6H5), 2.38 (s, 3H, eCH3),1.96 (s, 3H, eCH3), e0.72 (s, 6H,
d

18
C.-T. Chen et al. / Journal of Organometallic Chemistry 753 (2014) 9e19
AleCH3). 13C NMR (150 MHz, CDCl3):
d
(ppm) 151.0, 143.8, 142.5,
mixture was stirred at prescribed temperature for the prescribed
135.2, 130.9 (CipsoeC6H5), 131.4, 130.7, 129.3, 128.0, 125.3, 125.2,
123.8, 108.8 (CHeC6H5), 13.0 (eCH3), 12.7 (eCH3), e9.8 (AleCH3).
time. After the reaction was quenched by the addition of 5 mL acetic
acid solution (0.35 N), the resulting mixture was poured into 25 mL
n-heptane to precipitate polymers. Crude products were recrys-
tallized from THFehexane and dried in vacuo up to a constant
weight. Conversion was determined from 1H NMR in CDCl3 by
comparison with remaining monomer.
27Al NMR (156 MHz):
d
142.0 (Dn1/2 ¼ 9324.6).
4.22. (NPzMeSO2PhMe)AlMe2 (9)
The procedure for the preparation of 9 was similar to that used
for 1 but with HNPzMeSO2PhMe (0.341 g, 1.0 mmol). A white solid
was obtained (0.278 g, 70.0%). Anal. Calc. for C20H24N3O2SAl: C,
60.44; H, 6.09; N, 10.57. Found: C, 60.19; H, 5.83; N, 10.38. 1H NMR
4.25. Crystal structure data
Crystals were grown from CH2Cl2/hexane solution for 2,
concentrated toluene solution 50, THF/hexane solution 8 and
concentrated CH2Cl2 solution N(SO2PhF)2PzH and isolated by
filtration. Suitable crystals were mounted on Mounted CryoLoop
(HAMPTON RESEARCH, size: 0.5e0.7 mm) using per-
fluoropolyether vacuum oil (Aldrich, FOMBLINÒY) and cooled
rapidly in a stream of cold nitrogen gas using an Oxford Diffraction
Limited GEMINT S. For crystals 6 and 7, empirical absorption
correction was based on spherical harmonics, implemented in
SCALE3 ABSPACK scaling algorithm from CrysAlis RED, Oxford
Diffraction Ltd. The space group determination was based on a
check of the Laue symmetry and systematic absences and was
confirmed using the structure solution. The structure was solved by
direct methods using a SHELXTL package [52]. All non-H atoms
were located from successive Fourier maps, and hydrogen atoms
were refined using a riding model. Anisotropic thermal parameters
were used for all non-H atoms, and fixed isotropic parameters were
used for H atoms. Some details of the data collection and refine-
ment are given in Table 2 (for 2, 50 and 8) and Table S1 [for
HN(SO2PhF)2PzH].
(600 MHz, CDCl3):
d
(ppm) 7.85 (dd, J ¼ 7.8 & 1.5 Hz, 1H, C6H5), 7.41
(m, 1H, C6H5), 7.26e7.29 (overlap, 2H, C6H5), 7.19 (td, J ¼ 7.8 &
1.0 Hz, 1H, C6H5), 6.94e6.98 (overlap, 3H, C6H5), 5.99 (br, 1H, C6H5),
2.39 (s, 3H, eCH3), 2.29 (s, 3H, eCH3), 1.98 (s, 3H, eCH3), e0.72 (s,
6H, AleCH3). 13C NMR (150 MHz, CDCl3):
d (ppm) 151.4, 143.7, 141.1,
140.2, 136.0, 131.0 (CipsoeC6H5), 131.4, 129.7, 128.7, 125.8, 125.0,
123.8, 108.8 (CHeC6H5), 21.3 (eCH3), 13.4 (eCH3), 12.8 (eCH3), e9.6
(AleCH3). 27Al NMR (156 MHz):
d
117.4 (Dn1/2 ¼ 8559.8).
4.23. (NPzMeSO2PhTriMe)AlMe2 (10)
The procedure for the preparation of 10 was similar to that used
for 1 but with HNPzMeSO2PhTriMe (0.369 g, 1.0 mmol). A white solid
was obtained (0.258 g, 65.0%). Anal. Calc. for C20H24N3O2SAl: C,
62.10; H, 6.63; N, 9.87. Found: C, 62.42; H, 7.10; N, 9.86. 1H NMR
(600 MHz, CDCl3):
d
(ppm) 7.63 (d, J ¼ 8.4 Hz, 1H, C6H5), 7.28 (t,
J ¼ 7.2 Hz, 1H, C6H5), 7.15 (t, J ¼ 7.2 Hz, 1H, C6H5), 7.01 (d, J ¼ 7.8 Hz,
1H, C6H5), 6.70 (br, 2H, C6H5), 6.17 (br, 1H, C6H5), 2.40 (s, 3H, eCH3),
2.31 (s, 6H, o-CH3ePh), 2.18 (s, 3H, p-CH3ePh), 2.07 (s, 3H, eCH3), e
0.75 (s, 6H, AleCH3). 13C NMR (150 MHz, CDCl3):
d (ppm) 151.6,
144.2, 140.4, 138.7, 136.2, 131.6 (CipsoeC6H5), 131.1, 129.6, 129.3,
125.0, 124.4, 108.9 (CHeC6H5), 22.6 (o-CH3ePh), 20.6 (p-CH3ePh),
13.3 (eCH3), 12.4 (eCH3), e9.4 (AleCH3). 27Al NMR (156 MHz):
Acknowledgements
We would like to thank the National Science Council of the
Republic of China for financial support (grant number NSC 98-2113-
M-005-002-MY3 and NSC 101-2113-M-005-012-MY3).
d
109.6 (Dn1/2 ¼ 8913.9).
4.24. Polymerization procedure of ε-caprolactone
Appendix A. Supplementary data
Typically, to a flask containing prescribed amount of monomers
(ε-caprolactone) and catalyst precursors (0.125 mmol) were added
15 mL (containing 0.25 mmol benzyl alcohol) toluene. The reaction
Supplementary data related to this article can be found at http://
dx.doi.org/10.1016/j.jorganchem.2013.12.022.
Table 2
References
Summary of crystal data for compounds 2, 50 and 8.
2
50
8
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4978.
Formula
Fw
T, K
C20H25AlN2O3S
400.46
100(2)
Monoclinic
P2(1)/n
9.6494(7)
19.8856(14)
10.5417(9)
90
97.995(7)
90
2003.1(3)
4
1.328
0.228
9864
244
0.0731
0.1329
1.000
C33H31AlN6O4S2
666.74
100(2)
Monoclinic
C2/c
18.547(2)
14.6025(12)
12.6021(13)
90
115.724(14)
90
3074.7(5)
4
1.440
0.252
12,588
217
C19H22AlN3O2S
383.44
100(2)
Monoclinic
Cc
14.8142(4)
9.1392(4)
16.1837(6)
90
116.253(6)
90
1965.10(12)
4
Crystal system
Space group
ꢀ
a, A
ꢀ
b, A
ꢀ
c, A
aꢀ
bꢀ
gꢀ
3
ꢀ
V, A
z
rcalc, Mg/m3
1.296
0.227
m
(Mo K
a
), mmꢁ1
Reflections collected
10,556
235
0.0409
0.1075
0.991
No. of parameters
R1a
0.0503
0.1135
1.002
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(2010) 3564e3572.
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(2004) 5155e5162.
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[19] J. Wu, X. Pan, N. Tang, C.-C. Lin, Eur. Polym. J. 43 (2007) 5040e5046.
wR2a
GoFb
a
R1 ¼ [SjF0j ꢁ jFcj]/SjF0j]; wR2 ¼ [Sw(F20 ꢁ Fc2)2/Sw(F02)2]1/2, w ¼ 0.10.
b
GoF ¼ [Sw(F20 ꢁ F2c)2/(Nrflns ꢁ Nparams)]1/2
.

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19
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