Zhang Jun-Hui, Nong Rui-Yu, Xie Sheng-Ming, Wang Bang-Jin, Ai Ping, Yuan Li-Ming
Department of Chemistry, Yunnan Normal University, Kunming, P.R. China.
Electrophoresis. 2017 Oct;38(19):2513-2520. doi: 10.1002/elps.201700122. Epub 2017 Jul 26.
Natural amino acids are well known to form coordination polymers with transition metal ions. In this study, six homochiral metal-organic frameworks constructed from Zn or Co ions and various enantiopure amino acid (L-tyrosine, L-histidine, L-tryptophan and L-glutamic acid), namely [Zn(L-tyr)] (L-tyrZn), [Zn (btc) (Hbtc)(L-His) (H O) ]·1.5H O, {[Zn (L-trp) (bpe) (H O) ]·2H O·2NO } , [Co (L-Trp)(INT) (H O) (ClO )], [Co (sdba)((L-Trp) ] and [Co(L-Glu)(H O)·H O] , were synthesized according to the methods previously reported in the literature. The six homochiral MOFs were explored as the chiral stationary phases for high-performance liquid chromatographic separation of enantiomers using hexane/isopropanol or hexane/dichloromethane as mobile phase. Various types of enantiomers such as alcohols, amines, ketones, ethers, organic acids, etc. can be resolved on these homochiral MOF columns. The results revealed that the enantioseletivities of homochiral MOFs based on amino acids as chiral bridging ligands used as stationary phases are practical in HPLC.
天然氨基酸与过渡金属离子形成配位聚合物是众所周知的。在本研究中，通过锌或钴离子与各种对映体纯氨基酸（L-酪氨酸、L-组氨酸、L-色氨酸和L-谷氨酸）构建了六种手性金属有机框架，即[Zn(L-tyr)]（L-tyrZn）、[Zn(btc)(Hbtc)(L-His)(H₂O)]·1.5H₂O、{[Zn(L-trp)(bpe)(H₂O)]·2H₂O·2NO₃}、[Co(L-Trp)(INT)(H₂O)(ClO₄)]、[Co(sdba)((L-Trp)]和[Co(L-Glu)(H₂O)·H₂O]，按照文献中先前报道的方法进行合成。将这六种手性金属有机框架用作手性固定相，以正己烷/异丙醇或正己烷/二氯甲烷为流动相，用于高效液相色谱分离对映体。各种类型的对映体，如醇类、胺类、酮类、醚类、有机酸等，都可以在这些手性金属有机框架柱上实现拆分。结果表明，基于氨基酸作为手性桥连配体的手性金属有机框架用作固定相时，其对映选择性在高效液相色谱中具有实用性。
