The 1,3-dipolar cycloaddition between glycine-derived azlactones with maleimides is efficiently catalyzed by the dimeric chiral complex [(Sa)-Binap·AuTFA]2. The alanine-derived oxazolone only reacts with tert-butyl acrylate giving anomalous regiochemistry, which is explained and supported by Natural Resonance Theory and Nucleus Independent Chemical Shifts calculations. The origin of the high enantiodiscrimination observed with maleimides and tert-butyl acrylate is analyzed using DFT computed at M06/Lanl2dz//ONIOM(b3lyp/Lanl2dz:UFF) level. Several applications of these cycloadducts in the synthesis of new proline derivatives with a 2,5-trans-arrangement and in the preparation of complex fused polycyclic molecules are described.
1,3-二极环加成反应是由二聚手性复合物[(Sa)-Binap·AuTFA]2高效催化的,该反应涉及甘氨酸衍生的氮内酯与马来酰亚胺的反应。丙氨酸衍生的氧代噁唑酮只与叔丁基丙烯酸酯发生反应,产生异常的区域化学反应,这一现象通过自然共振理论和核独立化学位移计算得到解释和支持。观察到的与马来酰亚胺和叔丁基丙烯酸酯的高对映选择性的起源是通过使用M06/Lanl2dz//ONIOM(b3lyp/Lanl2dz:UFF)水平的密度泛函理论进行分析。描述了这些环加成产物在合成新的脯氨酸衍生物中的几种应用,这些衍生物具有2,5-trans排列,以及在制备复杂的融合多环分子中的应用。