title: Effect of the residual silanol group protection on the liquid chromatographic resolution of racemic primary amino compounds on a chiral stationary phase based on optically active (3,3'-diphenyl-1,1'-binaphthyl)-20-crown-6.
abstract: A liquid chromatographic chiral stationary phase (CSP) based on (3,3'-diphenyl-1,1'-binaphthyl)-20-crown-6, which has been utilized in the resolution of alpha-amino acids, amines and amino alcohols, was treated with excess of n-octyltriethoxysilane to prepare a new improved CSP. The residual silanol groups of the original CSP were protected by n-octyl groups in the new CSP. The chiral recognition ability of the new CSP was superior to that of the original CSP in the resolution of alpha-amino acids, amines and amino alcohols. Retention factors (k1) for the resolution of alpha-amino acids were lower on the new CSP than on the original CSP while those for the resolution of amines and amino alcohols were higher on the new CSP than on the original CSP. The improved chiral recognition ability of the new CSP and the retention behaviors of the two enantiomers on the new CSP have been rationalized to stem from the removal of the non-enantioselective interactions between the analytes and the residual silanol groups of the original CSP and the improved lipophilicity of the CSP.
authors.affiliation: Department of Chemistry and Chemistry Institute for Functional Materials, Pusan National University, Kuemjeong-Ku, Busan 609-735, South Korea. mhhyun@pusan.ac.kr
authors.forename: Myung Ho
authors.initials: MH
authors.lastname: Hyun
authors.forename: Sang Cheol
authors.initials: SC
authors.lastname: Han
authors.forename: Hee Jung
authors.initials: HJ
authors.lastname: Choi
authors.forename: Bu Sung
authors.initials: BS
authors.lastname: Kang
authors.forename: Hyun Ju
authors.initials: HJ
authors.lastname: Ha
mesh_terms: D000588:Amines / Q000032:analysis / Q000737:chemistry; D000596:Amino Acids / Q000032:analysis / Q000737:chemistry*; D000605:Amino Alcohols / Q000032:analysis / Q000737:chemistry; D002853:Chromatography, Liquid / Q000379:methods*; D015203:Reproducibility of Results; D012821:Silanes / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000588:Amines; D000596:Amino Acids; D000605:Amino Alcohols; D012821:Silanes; C082343:silanol