1314501-07-9Relevant academic research and scientific papers
Bidentate Schiff bases derived from (S)-α-methylbenzylamine as chiral ligands in the electronically controlled asymmetric addition of diethylzinc to aldehydes
Jaworska, Magdalena,Welniak, Miroslaw,Zieciak, Justyna,Kozakiewicz, Anna,Wojtczakb, Andrzej
experimental part, p. 189 - 204 (2011/08/21)
A group of bidentate Schiff bases derived from enantiomerically pure (S)-α-methylbenzylamine was synthesized. Crystal structure was determined for three compounds. Schiff bases were used as chiral ligands in the asymmetric addition of Et2Zn to aldehydes. The obtained enantioselectivity was e.e.=8-94% depending on the substrate and the best was observed for (S,E)-2-(1-(1-phenylethylimino)-ethyl)phenol. The enantioselectivity increase was connected with the substituent-induced electronic effects in the substrate molecules. Molecular modeling resulted in the models of the 3D structures of Zn-Zn complex catalysts containing investigated Schiff bases, which were consistent with the reported chirality of the addition product and explained observed e.e. The presented transition state models allow explaining the change of the absolute configuration of diethylzinc addition product in the case of using ortho-substituted aldehydes. ARKAT-USA, Inc.
