Synthesis of Calix[4]proline Derivatives and Their Chiral Recognition for Enantiomers of Mandelic Acid

Abstract

Five chiral calix[4]proline derivatives were designed and synthesized from aminocalix[4]arenes, and their structures were characterized by 1 H NMR, 13 C NMR, IR, ESI-MS and elemental analysis. The chiral recognition ability for enantiomers of mandelic acid was investigated by NMR techniques, and the results showed that 5,11-diprolinamides substituted calix[4]arene 2b could well and selectively recognize the two enantiomers of mandelic acid (K L /K D 94). A possible recognition mechanism was proposed, which was constructed by cooperative multi-supramolecular interactions including intermolecular acid-base, hydrogen bond and π•••π stacking interactions.

Progress in Chiral Recognition Based on Molecular Tweezers

“…2007 年以来, He 等 [19][20] 2015 年, 李正义等 [26] 2015 年, Zhang 等 [27] 设计并合成了一系列以环己 图 12 化合物 25 与扁桃酸可能的识别机理 Figure 12 A possible recognition mechanism for compound 25 and mandelic acid Lhotak 等在 2014 年设计并合成了一种杯[4]芳烃衍 生物 43 [32] , 2015 年设计合成了硫杂杯[4]芳烃衍生物 44 [33] [34] . 但 SFC 对仪器要求较高, 普及性较差, 这在一定 程度上限制了该技术的应用 [35] .…”

Enantioselective liquid‐liquid extraction of DL‐mandelic acid using chiral diphosphine ligands as extractants

“…The chemical structure of mandelic acid is shown in Figure 2. Derivatives of cyclodextrin, 24 tartaric acid, 25 and proline 26 are common chiral extractants used in resolution of DLmandelic acid. The chiral center of mandelic acid is similar to the chiral center of amino acid, which has carboxyl group and heteroatoms with lone pair electrons.…”