Heterogenization of a chiral bis(oxazoline) catalyst by grafting onto silica.
[reaction: see text] We report here the first heterogenization of a bis(oxazoline) ligand on an inorganic (silica) surface. The activity and enantioselectivity of this new material as a catalyst for the Diels-Alder reaction were checked, and it was shown that under certain conditions enantioselectivities similar to those of the homogeneous catalyst are reached. It was also shown that under these conditions the catalyst can be recycled without loss of activity or selectivity.
Rechavi
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Laboratoire de Catalyse et Synthèse Organique (U.C.B.L.-C.P.E.), 43 bld du 11 nov. 1918, 69622 Villeurbanne Cedex, France.
Lemaire
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