SUPPORTING INFORMATION FOR
Controlled synthesis of new amphiphilic glycopolymers with liquid crystal
grafts
Khalid FERJI1,2, Cécile NOUVEL1,2, Jérôme BABIN1,2, Pierre-Antoine ALBOUY3, Min-Hui LI4, Jean-Luc
SIX1,2*
1) Université de Lorraine, Laboratoire de Chimie Physique Macromoléculaire LCPM, FRE 3564, Nancy
F-54000, France
2) CNRS, Laboratoire de Chimie Physique Macromoléculaire LCPM, FRE 3564, Nancy F-54000, France
3) Université Paris-Sud, CNRS, Laboratoire de Physique des Solides, UMR 8502, 91405 Orsay Cedex,
France
4) Institut Curie, CNRS, Université Pierre et Marie Curie, Laboratoire Physico-chimie Curie, UMR 168,
26 rue d'Ulm, 75248 Paris cedex 05, France
MATERIALS
Triethylamine
(Et3N,
99%),
cholesterol
(94%),
p-toluenesulfonyl
chloride
(TsCl,
>99%),
trimethylamine hydrochloride (98%), diethylene glycol (DEG, >99%), acryloyl chloride (> 98%) were
used as received from Aldrich. Dichloromethane (CH2Cl2) and dioxane were dried over calcium
hydride and then distilled under reduced pressure.
Step 1 of Scheme S1: Synthesis of cholesterol tosylate (Chol-OTs)
Cholesterol (10 g, 0.026 mol) was dissolved in dry dichloromethane (60 mL), then triethylamine (9
mL, 0.065 mol) was added at room temperature. A mixture of TsCl (7.4 g, 0.039 mol) and
trimethylamine hydrochloride (0.247 g, 0.0026 mol) in dichloromethane (40 mL) was added dropwise
at 0 °C. After 2 hours stirring at room temperature, salts formed during reaction were filtered and
solvent was partially evaporated. The organic layer was washed with 100 mL of brine solution, and
then dried over anhydrous magnesium sulfate. After removing solvent under reduced pressure, the
crude solid was washed with 100 mL of MeOH, then dried under vacuum over night. A white powder
was obtained (12.5 g, 87% yield) and characterized by 1H NMR in CDCl3 (Figure S1).
Step 1
TsCl / Me3N-HCl /NEt3 /CH2Cl2
2h, y=87%
O
S O
O
HO
Chol-OTs
Cholesterol
Step 2
DEG/dioxane
100°C, 2h, y=90%
O
O
O
O
O
HO
O
CholDEG
DEGCholA
Step 3
Acryloyl chloride / NEt3 / CH2Cl2
2h, y=66%
Scheme S1. Synthesis of DEGCholA. y correspond to the yield of each step
j
O
m
H H
h
j
h
H H
H
O
O
l
Ha
O
H
H
i
k
m
H
i h
H
H H
H
h
k l
h
i
j
b
(4)
b
a
f
f
g
f
O
f
f
aH
O
HO
H
a
b
b
g
(3)
c
d
d
H
H
c
a
O
e
H3C
S
H
O
O
d
(2)
H
H
c
H
b
e
b
a
a
H
HO
H
(1)
b
b
a
Figure S1. 1H NMR spectra in CDCl3 of (1) Cholesterol, (2) Chol-OTs, (3) CholDEG, (4) DEGCholA.
Step 2 of Scheme S1: Synthesis of cholesterol diethylene glycol (CholDEG)
A mixture of Chol-OTs (10 g, 0.0185 mol) and DEG (52.7 mL, 0.555 mol) in 50 mL of dioxane was
refluxed for 2 hours. After dioxane evaporation, CholDEG was extracted from DEG phase using
petroleum ether; then solvent was evaporated. Crude product was dissolved in CH2Cl2, treated with
100 mL of brine solution, dried over magnesium sulphate. After solvent evaporation, a white waxy
solid was obtained after purification using flash silica gel chromatography (Petroleum ether /ethyl
acetate (90/10, v/v) as eluent). Pure product has been characterized by 1H NMR in CDCl3 (Figure S1).
Step 3 of Scheme S1: Synthesis of DEGCholA
2.7 mL (0.025 mol) of acryloyl chloride was added dropwise to a mixture of 8 g (0.017 mol) of
CholDEG and 7 mL (0.051 mol) of triethylamine in 80 mL of dry dichloromethane at 0 °C. After 2
hours stirring at room temperature, the mixture was washed with 100 mL of brine solution, dried
over magnesium sulphate, then the solvent was evaporated. DEGCholA was purified using flash silica
gel chromatography (Petroleum ether /ethyl acetate (70/30, v/v) as eluent), then characterized by 1H
NMR in CDCl3 (Figure S1).
RESULTS AND DISCUSSION
1) Synthesis of diethylene glycol cholesteryl ether acrylate (DEGCholA)
DEGCholA has been prepared by a three-step synthesis as described in Scheme S1. Firstly, cholesterol
was activated by p-toluenesulfonyl chloride (TsCl) to give cholesterol tosylate (Chol-OTs). Chol-OTs
has been characterized by 1H NMR (CDCl3) and characteristic peaks of tosyl group were observed at
7.3 and 7.8 ppm (Figure S1). One can also see a shift of the peak characteristic of proton (a) from 3.5
ppm (cholesterol) to 4.3 ppm (Chol-OTs). In the second step, Chol-OTs was reacted with an excess of
DEG to yield CholDEG. After purification, 1H NMR characterization was carried out to check the purity
of this product (Figure S1). Peaks characteristic of tosyl group had disappeared, while protons (f)
peak can be seen around 3.7 ppm and proton (a) peak has been shift to 3.3 ppm. Area ratio between
peaks (f) and peak (a) or (b) corresponds to the expected value for CholDEG structure. Finally,
DEGCholA has been obtained by reaction between CholDEG and acryloyl chloride. As shown in Figure
S1, doublet peaks characteristic of vinyl protons (l and m) are located at 5.8 and 6.4 ppm,
respectively. Vinyl proton (k) has a chemical shift around 6.15 ppm. On other hand, protons of
diethylene glycol linkage are shown with three peaks from 3.5 to 4.5 ppm.
2) Stability of PDEGCholA in basic medium
O
h2
H
H
h2
h
H
h a
H
H
O
O
O
n
H
H
h1 h1
H
h
H
H
h
b
h
b
h2
h1
a
(2)
a
(1)
h
h1
b
h2
Figure S2. 1H NMR spectra in CDCl3 of PDEGCholA before (1) and after (2) alkaline treatment
FIGURE S3. FTIR spectra of AChol [a) before. b) after basic conditions] and DEGCholA [c)
before. d) after basic conditions]
3) Homopolymerization of DEGCholA by ATRP
h2 h2
O
H
H
h
h
H
H
a
H
j
O
O
O
H
n
H
h1 h1
O
b
H
H
h
h
H
j
h h
H H
H H
m
a
H
O
H
O
O
H
H
k
l
H
H
H H
i
i
h h
H
b
(h+h1)
(h2)
(b)
(2)
(a)
(h+h1)
(b)
(1)
(m) (k) (l)
(j )
(h2) (i)
(a)
FIGURE S4. 1H NMR spectra in CDCl3 of crude PDEGCholA (1) and purified PDEGCholA (2)
4) Mesomorphic properties of DEGCholA, PDEGCholA and graft copolymers Dex-g-PDEGCholA
I
SmAd
Copolymer-2nd heating
Crystal
Heat Flow (Endo up)
Heat Flow (Endo up)
g
Isotropic
1st heating
SmX
SmAd
Homopolymer-2nd heating
2nd heating
Homopolymer-2nd cooling
1st cooling
Copolymer-2nd cooling
2nd cooling
0
30
60
o
Temperature ( C)
(A)
90
0
50
100
150
200
o
Temperature ( C)
(B)
Figure S5. DSC thermograms of monomer DEGCholA recorded at 1°C min-1 (A) and of homopolymer
PDEGCholA and graft copolymer Dex-g1.6-PDEGCholA79 recorded at 10°C min-1 (B). g represent glassy
state, SmAd the interdigitated smectic A phase, SmX the unidentified smectic phase and I the
isotropic phase.