C2-Symmetric chiral diamine ligands for enantiomeric recognition of amino acid esters and mandelic acid by proton NMR titration method

Authors : Hayriye ARAL, Tarık ARAL, Mehmet ÇOLAK, Berrin ZİYADANOĞULLARI, Recep ZİYADANOĞULLARI

Pages : 374-382

Doi:10.3906/kim-1207-58

View : 14 | Download : 4

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :Two novel C2-symmetric chiral diamines containing a -phenylethyl and a -insert ignore into journalissuearticles values(1-naphthyl);ethyl chiral subunits were prepared with quantitative yields. Enantiomeric recognition properties of these simple structured diamine ligands towards D- and L-amino acid esters and D- and L-mandelic acid were examined by the 1H NMR titration method. These ligands exhibited strong complexation insert ignore into journalissuearticles values(with Kf up to 2481 M-1); and good enantioselectivity insert ignore into journalissuearticles values(up to KL/KD = 4.08); towards the mandelic acid enantiomers. The results show that simple structured and easily accessible acyclic C2-symmetrical compounds can also be used for enantiomeric recognition of racemic amino acids and mandelic acid in addition to complex molecules such as crown ethers and other cyclic molecules.
Keywords : Enantiomeric recognition, C2 symmetric, chiral diamines, amino acids, mandelic acid, NMR titration