4th EucheMs chemistry congress

Poster Session 2
s1198
chem. Listy 106, s257–s1425 (2012)
Poster session 2 - solid state chemistry
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BinoL And SynthetiC BinoL derivAtiveS AS
PotentiAL ChirAL reSoLvinG AGentS
e. euSeBio 1 , t. M. r. MAriA 1 , J. CAnotiLho 2 ,
r. M. B . CArriLho 2 , A. r. ABreu 2 , M. M. PereirA 2
1 University of Coimbra, Chemistry, Coimbra, Portugal
2 University of Coimbra, Faculdade de Farmácia, Coimbra,
Portugal
BINOL was synthesized for the first time in 1926, but its
ongoing interest as chiral inducer was only recognized after
Noyori (Nobel Prize, 2001) discovered its application as ligand
in the asymmetric catalytic reduction of aldehydes, in 1979 [1] .
Since then, the synthetic chemical modifications on BINOL
molecule received enormous attention, mainly to obtain new
chiral ligands for several asymmetric catalytic reactions [2] .
BINOL was also recently described as an useful co-former
for resolution of racemic mixtures by co-crystallization [3] . The use
of stereoselective co-crystals represents an alternative strategy for
chiral resolution, which is of particular relevance for substances
which do not have the appropriate functional group to readily give
rise to salts.
In this communication results on the investigation of the
potential of BINOL and some synthetic BINOL derivatives as
chiral resolving agents for selected chiral active pharmaceutical
ingredients and diols are presented. Mixtures of the solid
components, in different molar ratios, are submitted to
mechanochemical methods which have proven to be an efficient
method of co-crystal synthesis [4] . The outcomes of this process
are evaluated by differential scanning calorimetry, polarized light
thermomicroscopy and infrared spectroscopy.
Acknowledgments: The authors thank for financial support to
Programa Compete and QREN/FEDER/FCT (PTDC/QUI-
QUI/112913/2009).
references:
1. R. Noyori, I. Tomino, Y. Tanimoto J. Am. Chem. Soc., 101
(1979) 3129.
2. A. R. Abreu, M. Lourenco, D. Peral, M. T. S. Rosado,
M. E. S. Eusébio, Palacios, J. C. Bayón, M. M. Pereira, J.
Mol. Catal. A: Chem.325 (2010) 91.
3. B. N. Roy, G. P. Singh, D. Srivastava, H. S. Jadhav,
M. B. Saini, U. P. Aher, Org. Process Res. Dev., 13 (2009)
450.
4. R. A. E. Castro, J. D. B. Ribeiro, T. M. R. Maria,
M. Ramos Silva, C. Yuste-Vivas, J. Canotilho,
M. E. S. Eusébio, Cryst. Growth Des., 11 (2011) 5396.
Keywords: Binol; Co-crystal;
4 th EucheMs chemistry congress
P - 0 6 7 2
rotAtionAL eCho douBLe reSonAnCe A
vALuABLe tooL to inveStiGAte the SurfACe
CheMiStry of MetAL nAnoPArtiCLeS
t. GutMAnn 1 , e. BonnefiLLe 1 , h. BreitzKe 2 ,
P. J. deBouttiere 1 , K. PhiLiPPot 1 ,
G. BuntKowSKy 2 , B. ChAudret 3
1 CNRS-LCC, Universite de Toulouse, Toulouse Cedex 4,
France
2 TU Darmstadt, Physical Chemistry, Darmstadt, Germany
3 CNRS INSA LPCNO, Universite de Toulouse, Toulouse
Cedex 4, France
In the last decade the attention devoted to metal
nanoparticles (MNPs) has been growing up rapidly, particularly
due to their high application potential in colloidal and
heterogeneous catalysis, i.e. hydrogenation, C-C coupling and
oxidation reactions. The investigation of their surface chemistry
is a crucial topic to understand the catalytic properties and to tune
them up for technical reactions, as for example for
Fischer-Tropsch, watergas-shift reaction, arene hydrogenation etc.
To characterize ligands, probe molecules or intermediates
on the surface of MNPs solid-state NMR has been demonstrated
to be one method of choice. It allows getting information about
their location and dynamics which is important to understand their
organization on the surface. In the present work the distance
measurement between stabilizing ligands and carbon monoxide
(CO) reactive molecules at the surface of phosphine-stabilized
ruthenium nanoparticles (RuNPs) is demonstrated employing
Rotational Echo Double Resonance (REDOR) experiments. The
studied model systems are RuNPs in the size range 1-2 nm
stabilized with 1,3,5-triaza-7-phosphaadamantane (PTA) or
triphenylphosphine (PPh ) ligands after exposure under CO
3
atmosphere. This REDOR study sheds more light on interactions
between reactive probe molecules and ligands as well as on their
binding geometries at the surface and helps the interpretation of
complex solid-state MAS NMR spectra of ligand stabilized
RuNPs. Further, this study builds up the basis for advanced
mechanistic investigations of complex MNPs systems.
Keywords: NMR spectroscopy; Nanoparticles; Phosphane
ligands; Surface Chemistry; Ruthenium;
AUGUst 26–30, 2012, PrAGUE, cZEcH rEPUbLIc