Asymmetric diethylzinc addition to N-sulphonyl and N-phosphinoyl arylaldimines

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2013
Çağlı, Eda
Design of new chiral ligands for asymmetric synthesis is important. The ligand should be economical and efficient in enantioselective transformations. For the synthesis of some natural products and biologically active compounds, optically active amines are used as important intermediates. For this reason, it is significant to develop new catalyst system which can produce optically active amines in an economical and efficient way. Our group developed PFAM ligands and used successfully for the enantioselective synthesis of organic compounds. In this work, these ligands were tested as chiral catalysts for enantioselective synthesis of amines. N-sulphonyl and N-phosphinoyl imines synthesized from aromatic aldehydes were used as the starting material for enantioselective diethylzinc addition reaction in the presence of copper salt and PFAM ligands. By improving the known procedure, N-benzylidine sulphonylaldimine was obtained in excellent yield (98%). Asymmetric diethylzinc addition reaction to N-sulphonyl and N-phosphinoyl aryaldimines provided chiral amines in up to 81% enantioselectivity and 99% yield.

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Citation Formats
E. Çağlı, “Asymmetric diethylzinc addition to N-sulphonyl and N-phosphinoyl arylaldimines,” M.S. - Master of Science, Middle East Technical University, 2013.