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چکیده
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Enantioselective allylic oxidation of alkenes using organic peresters and copper chiral complexes has been a subject of great interest during the last decade. This reaction provides an access to chiral allylic alcohols which are key intermediates in the synthesis of natural products. Limited natural resources and an increasing demand for enantiomerically pure compounds render catalysis and especially chiral heterogeneous catalysis a key technology and many researchers have taken great interest in these catalysts which is mainly due to the simple filtration and reuse of expensive chiral catalysts and ease of separation. In this project, we use (S)-2-amino-2-phenylethanol and (S)-2-amino-3-phenylpropanol which are synthesis by reducing of their corresponding amino acids, as ligands and immobilizing on the modified silica nanoporous SBA-15. Obtained new heterogeneous ligands characterized by TGA, DTA, XRD, EDX, SEM, and FT-IR. The catalytic potential of these new heterogeneous ligands was applied for the copper catalyzed allylic C-H bond oxidation of cycloolefins. The allylic esters were prepared in good yields and moderate to good enantioselectivities.
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