Calixarene based chiral solvating agents for ?-hydroxy carboxylic acids

Küçük Resim Yok

Tarih

2013

Dergi Başlığı

Dergi ISSN

Cilt Başlığı

Yayıncı

Elsevier

Erişim Hakkı

info:eu-repo/semantics/closedAccess

Özet

Novel chiral calix[4]arene derivatives functionalized at the lower rim have been prepared from the reactionof p-tert-butylcalix[4]arene diamine derivative with N-Phthaloyl-L-phenylalanine or (2S)-2-((benzyloxy)carbonyl)amino)-3-hydroxypropanoic acid or (2S,3R)-2-((benzyloxy)carbonyl)amino-3-hydroxybutanoic acid in 63-81% yield. The structures of these receptors were characterized by FTIR, H-1, C-13 and 2D COSY NMR spectroscopy. The enantioselective recognition of these receptors towards the enantiomers of racemic carboxylic acids was studied by H-1 NMR spectroscopy. The molar ratios of the chiral compounds with each of the enantiomers of guests were determined by using Job plots. The Job plots indicate that the hosts form 1:2 instantaneous complexes with all guests. The receptors exhibited different chiral recognition abilities toward the enantiomers of racemic guests. NMR studies demonstrated that the receptors function as highly effective chiral shift reagents for determining the enantiomeric purity of a series of carboxylic acids. (c) 2013 Elsevier B.V. All rights reserved.

Açıklama

Anahtar Kelimeler

Chiral Calixarene, Enantiomeric Recognition, Nmr Spectroscopy, Carboxylic Acids

Kaynak

Journal Of Molecular Structure

WoS Q Değeri

Q3

Scopus Q Değeri

Q2

Cilt

1048

Sayı

Künye