# Supplementary Material (ESI) for Chemical Communications
# This journal is © The Royal Society of Chemistry 2004
UV Vis spectra:
β-diketones adopt 2 forms in equilibrium as shown on scheme. The enol form is stabilised by
a strong conjugation of π-system and an intramolecular hydrogen bond, whereas the diketo
form is destabilised by a dipole-dipole repulsion of the 2 carbonyl groups.
O
H
O
O
Ke
Diketo Form
O
Cis-Enol Form
The stabilization of the Enol form by intramolecular hydrogen bonding is more pronounced
when no competition exists with the solvent. Hence, keto-enol equilibria of β-diketone
compounds are extremely solvent-sensitive, and the proportion of enol form is found to be
much greater in apolar or polar aprotic solvents, such as cyclohexane, than in polar protic
solvents, such as alcohol or water.
To illustrate the effect of medium polarity on the keto-enol equilibrium, we compared the
UV-visible spectra of SDBM in an apolar solvent, Tetrahydrofuran (THF – blue curve) and in
a polar protic solvent, H2O (red curve). The peak at 360 nm is only due to enol form and the
peak at 280 nm is mainly due to keto form although the enol contributes to the absorption at
this point. 1,2 Therefore, UV-visible spectra gives direct information about the environment of
the probe.
Absorbance (a.u.)
1.5
1 / THF
1 / H2O
1.0
0.5
0.0
200
300
400
 (nm)
500
The mesostructured materials contain 3 distinct regions: 3-5
Silica framework
Ionic interface of micelles
Hydrophobic interior of micelles
600
# Supplementary Material (ESI) for Chemical Communications
# This journal is © The Royal Society of Chemistry 2004
Spectra of as-prepared thin films exhibit are characteristic of apolar medium (similar to the
one observed in THF). This result confirms, in good agreement with 2D-GISAXS data, that βdiketone compounds are localized into the hydrophobic part of micelles (composed by alkyl
chains).
1,40
E
1 / As-prepared Films
Absorbance (a.u.)
-5
1 / THF (5.10 M)
1,05
0,70
5.4 mol. %
2.8 mol. %
1.4 mol. %
1.0 mol. %
0.7 mol. %
K
0,35
0,00
200
300
400
500
 (nm)
600
700
800
During the thermal treatment, keto peak appears, witnessing the probe medium polarity
increase probably promoted by the migration of a fraction of β1 compounds to the ionic
interface.
1,2
1 / Stiffened Films
Absorbance (a.u.)
E
0,9
-5
1 / THF (5.10 M)
K
5.4 mol. %
2.8 mol. %
1.4 mol. %
1.0 mol. %
0.7 mol. %
0,6
0,3
0,0
200
300
400
500
 (nm)
600
700
800
In fact, during the thermal treatment, we observe several changes:
the condensation of silica species leads to a contraction of the inorganic network,
the evaporation of water causes a decrease of the thickness of the ionic interface,
the complete hydrolysis of siloxane groups of the β1 compounds is achieved (β1 becomes
less hydrophobic and more polar).
All these changes lead to a migration of β1 compounds to the ionic interface.
# Supplementary Material (ESI) for Chemical Communications
# This journal is © The Royal Society of Chemistry 2004
FTIR spectra:
0,45
Before heating
0,40
After heating and washing
0,35
0,30
A
0,25
0,20
0,15
0,10
0,05
3900
3400
2900
2400
1900
1400
900
400
1/cm
(1)
Iglesias, E. Journal of Physical Chemistry 1996, 100, 12592.
(2)
Iglesias, E. J. Chem. Soc., Perkin Trans. 2 1997, 431.
(3)
Franville, A. C.; Dunn, B.; Zink, J. I. Journal of Physical Chemistry B 2001,
105, 10335.
(4)
Hernandez, R.; Franville, A.-C.; Minoofar, P.; Dunn, B.; Zink, J. I. Journal of
the American Chemical Society 2001, 123, 1248.
(5)
Minoofar, P. N.; Hernandez, R.; Chia, S.; Dunn, B.; Zink, J. I.; Franville, A.-C.
Journal of the American Chemical Society 2002, 124, 14388.