The condensation of β-keto enamine 1 with 5-methyltetronic acid takes an anomalous course. Single crystal X-ray analysis and chemical evidence establish the rearranged pyridine structure 15 for this condensation product.
β-酮烯胺1与5-甲基tetronic酸的缩合过程反常。单晶X射线分析和
化学证据确定了该缩合产物的重排
吡啶结构15。