Supporting Information
Highly Active Bifunctional Cobalt-salen Complexes for the Synthesis of
Poly(ester-b-carbonate) Copolymer via Terpolymerization of Carbon Dioxide,
Propylene Oxide, and Norbornene Anhydride Isomer: Roles of Anhydride
Conformation Consideration
Zhongyu Duan,a Xiaoyang Wang,a Qian Gao,a Li Zhang, a Binyuan Liu,*a
and Il
Kimb
a
Department of Polymer Science and Engineering, Hebei University of Technology, Tianjin
300130, China; Tel: +86-22-60204277; Email: byliu@hebut.edu.cn
b
BK21 PLUS Centre for Advanced Chemical Technology, Department of Polymer Science and
Engineering, Pusan National University, Busan 609-735, Korea; Tel: +82-51-5102466;
Email:ilkim@pusan.ac.kr
General procedure and materials
All manipulations of air and/or moisture-sensitive compounds were carried out using
standard Schenk techniques under pure nitrogen atmosphere. (1R, 2R)-1,
2-cyclohexanediamine was resolved from a technical grade cis-trans mixture in line
with literature.S1 Methyl 3-(3, 5-di-tert-butyl-4-hydroxyphenyl)propionate was dried
under vacuum before use. Acetonitrile was dried over calcium hydride under nitrogen
atmosphere. Methanol was distilled from sodium under nitrogen. Other Chemical
reagents were used as received.
1
Characterization
The 1H-NMR and 13C-NMR spectra were recorded on a Bruker AV 400 spectrometer
using tetramethylsilane as internal reference at room temperature. Infrared (IR)
spectra were recorded on a Bruker Vector 22 spectrometer from 400-4000 cm-1 at a
resolution of 4 cm-1 (16 scans collected). UV-visible spectroscopy was performed on a
UV-CARY300 spectrometer.
Synthesis of Ligand and Complex
Compound 1 was prepared according to reported process.S2 M.p: 64.7-66.0oC.
1
H-NMR (400MHz, CDCl3): δ=6.99 (s, 2H, Ph-H), 5.04(s, 1H, Ph-OH), 3.70(t, 2H,
CH2), 2.60(m, 2H, CH2),1.87(m,2H,CH2), 1.43(s,18H,t-Bu).
Scheme S1
Compound 2 was prepared according to modified process. S2 Alcohol 1 (6.01 g) and
HBr acid (100 mL) were placed in a flask and sealed and kept in oil bath at 90°C for 6
h. After cooling, the reaction mixture was extracted with benzene. The extract was
washed with water and aqueous solution of NaHCO3. The benzene extract was dried
with Na2SO4, and the solvent was evaporated. Yielded in 51%. 1H NMR (400MHz,
CDCl3): δ=7.01 (d, 1H, Ph-H), 6.89 (m, 1H, Ph-H), 6.58 (t, 1H, Ph-H), 4.62 (d, 1H,
2
Ph-OH), 3.39 (m, 2H, CH2Br), 2.70 (m, 2H, CH2), 2.11(m, 2H, CH2), and 1.39(s, 9H,
t-Bu) ppm.
Compound 3 was synthesized in light of modified procedure.S2 Yield in 92 %.
1
H-NMR(400MHz, CDCl3): δ=11.66(d, 1H, Ph-OH), 9.84(s, 1H, Ph-CHO), 7.35(d,
1H, Ph-H), 7.21(d, 1H, Ph-H), 3.38 (m, 2H, CH2), 2.80 (m, 2H, CH2), 2.18 (m, 2H,
CH2), and 1.40 (m, 9H, t-Bu) ppm.
Compound 4 was synthesized as reported in the literature.S2 Yield in 90%.
1
H-NMR(400MHz, CDCl3): δ=11.75(s, 1H, Ph-OH), 9.99(s, 1H, CHO), 7.63(s, 1H,
Ph-H), 7.34(s, 1H, Ph-H), 3.38(s, 4H, N-CH2), 2.80(s, 2H, Ph-CH2), 2.13(s, 2H,
-CH2-), 1.68-1.34(m, 12H, NCH2CH2CH2), 1.39(s, 9H, t-Bu), and 0.98(s, 9H, CH3)
ppm.
Synthesis of Salen Ligand (5) was synthesized as reported in the literature.S3 Yield in
96%. 1H-NMR(400MHz, CDCl3): δ 13.87(s, 2H, OH), 8.37(s, 2H, N=CH), 7.12(s, 2H,
Ph-H), 7.02(s, 2H, Ph-H), 3.45(s, 2H, cyclohexyl-CH), 3.40-3.20(m, 16H, NCH2),
2.65(s, 4H, Ph-CH2), 2.01(m, 4H, Ph-CH2CH2), 1.90-1.31(m, 8H, cyclohexyl-CH2),
1.30-1.15(t, 24H, CH2), 1.45(s, 18H, t-Bu), and 0.99(t, 18H, CH3).
13
C-NMR
(CDCl3, 100MHz): δ 165, 159, 137, 129, 128, 126, 122, 118, 71, 59, 58, 34, 33, 31, 29,
24, 19, and 13 ppm.
FT-IR, ν, cm-1: 3422, 2959, 2872, 1652, 1628, 1558, 1471,
1441, 1387, 1357, 1312, 1267, 1214, 1165, 1030,886, 801, 774, 752, 705, 530. Uv-Vis:
223, 260, and 335 nm.
Complex (6) was synthesized according to the literature.S4 Cobalt(II) acetate (0.48 g)
and the quaternary ammonium salt-appended Salen ligand (1.01 g) were dissolved in
3
methanol (10 mL). After stirring for 12 h at room temperature, LiCl (0.04 g, 1.0 mmol)
was added, and the mixture was further stirred for 12 h while oxygen was bubbled
through the reaction mixture. The solvent was removed in vacuo, and the residue was
extracted with methylene chloride. The organic layer was washed with saturated aq
NaHCO3 and brine and then dried over anhydrous sodium sulfate. The filtrate was
removed by reduced pressure distillation. The yield was 94 %.
1
H-NMR(400MHz, DMSO-d6): δ 7.61(s, 2H, N=CH), 7.22(s, 2H, Ph-H), 7.11(s, 2H,
Ph-H), 3.35(s, 2H, cyclohexyl-CH), 3.28-3.10(m, 16H, NCH2), 2.59(s, 4H, Ph-CH2),
1.95(m, 4H, Ph-CH2CH2), 1.90-1.52(m, 8H, cyclohexyl-CH2), 1.30-1.15(m, 24H,
CH2), 1.32(s, 18H, t-Bu), 1.89(t, 18H, CH3). FT-IR, ν, cm-1: 2958, 2872, 1636, 1532,
1458, 1439, 1384, 1320, 1239, 1204, 1166, 1034, 891, 784, 760, 539. Anal.Calcd for
C58H100ClCoN4O2Br2: C61.15, H8.79, N4.92; Found: C61.10, H8.79, N4.95. Uv-Vis:
233(shoulder peak), 262, and 411 nm.
Synthesis of complex (7) S4
Complex 6 (0.71g) was dissolved in methanol (50 mL) in a 80 mL Schlenk vial
wrapped in aluminum foil, and AgNO3 was added (0.43 g). The mixture was stirred
for 24 h at room temperature and then filtered to remove the Ag byproduct. The
solvent was removed in vacuo to afford the complex 7 as a dark green solid (0.47 g,
97%). 1H-NMR(400MHz, DMSO-d6): δ 7.79(s, 2H, N =CH), 7.36(s, 2H, Ph-H),
7.26(s, 2H, Ph-H), 3.35(s, 2H, cyclohexyl-CH), 3.28-3.10(m, 16H, NCH2), 2.59(s, 4H,
Ph-CH2), 1.95(m, 4H, Ph-CH2CH2), 1.90-1.52(m, 8H, cyclohexyl-CH2), 1.30-1.15(m,
24H, CH2), 1.32(s, 18H, t-Bu), and 1.89(t, 18H, CH3) ppm. FT-IR, ν, cm-1: 2958,
4
2873, 1636, 1532, 1438, 1384, 1240, 1167, 1031, 833, 783, 568. Anal. Calcd for
C58H100CoN7O11: C 61.65, H 8.86, N 8.68; Found: C 61.37, H 8.65, N 8.72. Uv-Vis:
232(shoulder peak), 262, and 410 nm.
Computational details
All calculations were performed using DMol3 (Materials Studio Software
version 4.2 from Accelrys Inc., www.accelrys.com) program package.
The
geometry
optimizations
were
performed
at
local
density
approximation level with Perdew–Wang functional (PWC) and
generalized gradient approximation level with BP functional having local
correlation
replaced
by
Vosko–Wilk–Nusair
(VWN)
functional
(VWN-BP).S5 The double numerical with polarisation (DNP) basis sets
were used for all the atoms in calculations. The sizes of these DNP basis
sets are comparable to the 6-31G** basis.S6 However, they are believed to
be much more accurate than Gaussian basis sets of the same size. S7 The
integration grid referred to as fine in the software program has been used
for optimization of the fragments.
References
S1. J. F. Larrow, E. N. Jacobsen, J. Org. Chem., 1994, 59, 1939-1942
S2. A. E. Prosenko, A. Skorobogatova O. I. Dyubchenko, P. I. Pinko,a N. V.
Kandalintseva, M. M. Shakirov, L. M. Pokrovsky, Russ. Chem. Bull., 2007, 56,
1119-1124.
S3. T. V. Hansen, L. Skattebøl, Tetrahedron. Lett., 2005, 46, 3829-3830.
5
S4. (a) L. P. C. Nielsen, C. P. Stevenson, D. G. Blackmond, E. N.Jacobsen, J. Am.
Chem. Soc., 2004, 126, 1360-1362. (b) S. Sujith, J. K. Min, J. E.Seong, S. J. Na, B.
Y. Lee, Angew. Chem. Int. Ed., 2008, 47, 7306-7309.
S5. Perdew, J. P.; Wang, Y. Phys. Rev. B 1992, 46, 6671–6687.
S6. Gordon, M. S. Chem. Phys. Lett. 1980, 76, 163–168.
S7. Delly, B. J. Chem. Phys. 2000, 113, 7756–7764.
Figure. S1. Illustrations of the DFT calculations for endo- and exo-NA involved
poly(ester-co-carbonate) fragments and polycarbonate fragment bearing no NA
fragments: optimized molecular structure with bond lengths
6
Figure. S2 The 1H NMR spectra of the raw copolymers obtained at 4 h and 8 h.
7
Figure. S3 The IR spectra of block copolymer before (A) and after (B) “thiol-ene”
reaction with β-mercaptoethanol.
8