Bogazici University, Chemistry Department, Bebek, Istanbul, Turkey.
Chirality. 2012 Jun;24(6):493-8. doi: 10.1002/chir.22007. Epub 2012 May 2.
Thermally interconvertible axially chiral 5-methyl-2-(o-aryl)imino-3-(o-aryl)-thiazolidine-4-ones have been synthesized diastereoselectively, and conformations of the major and minor enantiomeric pairs have been determined by (1)H nuclear magnetic resonance. Chromatographic resolutions of each compound have been performed by enantioselective high-performance liquid chromatography, and the barriers to rotation about the N(3)-C(aryl) bond have been determined by following the thermal interconversion process of the major to minor isomers until equilibrium. The rotational barriers range from 96.2 to 115.2 kJ/mol, depending on the size of ortho substituent on N(3)-aryl ring.
热致互变轴向手性 5-甲基-2-(邻芳基)亚氨基-3-(邻芳基)-噻唑烷-4-酮被立体选择性地合成，主要和次要对映异构体的构象通过（1）H 核磁共振确定。通过对映选择性高效液相色谱对每个化合物进行色谱拆分，并通过跟踪主要对映异构体向次要异构体的热互变过程，直到达到平衡，确定 N(3)-C(芳基)键旋转的势垒。旋转势垒范围为 96.2 至 115.2 kJ/mol，取决于 N(3)-芳基环上邻位取代基的大小。
