Solid Phase Behavior in the Chiral Systems of Various 2-Hydroxy-2-phenylacetic Acid (Mandelic Acid) Derivatives
作者:Jan von Langermann、Erik Temmel、Andreas Seidel-Morgenstern、Heike Lorenz
DOI:10.1021/je500845d
日期:2015.3.12
The solid phase behavior of a series of monosubstituted F-, Cl-, Br-, I-, and CH3- and two 2,4-halogen-disubstituted 2-hydroxy-2-phenylacetic acid (mandelic acid) derivatives was investigated. The study includes detailed information about melting temperature, melting enthalpy, Xray diffraction data, as well as selected binary phase diagrams of the respective chiral systems. Aside from the known metastable metastable conglomerates was found.
Synthesis of enantiopure 2-iodomandelic acid and determination of its absolute configuration by VCD spectroscopy
作者:Anikó Nemes、Elemér Vass、István Jalsovszky、Dénes Szabó
DOI:10.1007/s11696-018-0568-6
日期:2019.1
Racemic 2-iodomandelic acid 1 was synthesized from commercially available 2-iodobenzoic acid 2. Acyl chloride 3 was reacted with diethyl malonate, then the formed diester was hydrolysed and decarboxylated in a one-pot reaction. The obtained 2-iodoacetophenone 4 was reacted with bromine and the dibromoacetophenone derivative 5 was hydrolysed to give the racemic 2-iodomandelic acid (±)-1. Optical resolution
Chiral N-substituted secondary 1,2-aminoalcohols have been developed for the enantioseparation of ortho-halomandelic acids (o-X-MAs) via diastereomeric salt formation. Two structural isomers, N-methyl-2-amino-1,2-diphenylethanol and N-benzyl-2-amino-2-phenylethanol, showed high separation abilities for o-X-MAs (X = Cl, Br, I). The chiral recognition mechanism was elucidated by crystallographic analysis
手性N取代仲 1,2-氨基醇已开发用于通过非对映体盐形成原卤扁桃酸 ( o -X-MA) 的对映体分离。两种结构异构体N-甲基-2-氨基-1,2-二苯基乙醇和N-苄基-2-氨基-2-苯基乙醇对o -X-MA(X = Cl、Br、I)表现出较高的分离能力。通过难溶盐的晶体学分析阐明了手性识别机制。拆分剂氮原子上的取代基和结晶溶剂的包含稳定了盐并增强了它们的分离能力。