A new fragmentation reaction of 3-bromo-7-azabicyclo[2.2.1]hepta-2,5-diene carboxylic esters with 2-amino or 2-aminomethyl anilines is described. It leads to cis-5-(benzimidazol-2-yl)- or cis-5-(3,4-dihydroquinazolin-2-yl)-pyrroline-2-acetic acid esters. Substituents on the nitrogen atoms or in the aromatic ring are tolerated as long as they do not strongly reduce the nucleophilicity of the nitrogen atoms. The primary reaction products are not very stable but hydrogenation of the pyrroline and/or cleavage of the ester give products that are suitable for subsequent structural modifications, particularly ones that are interesting for combinatorial syntheses.
描述了一种新型的3-溴-7-氮杂环庚-2,5-二烯
羧酸酯与2-
氨基或2-
氨基甲基
苯胺的裂解反应。该反应生成的产物为顺式-5-(
苯并咪唑-2-基)或顺式-5-(3,4-二氢
喹唑啉-2-基)-
吡咯啉-
2-乙酸酯。只要不显著降低氮原子的亲核性,氮原子上的取代基或芳香环中的取代基均可耐受。初级反应产物相对不稳定,但对
吡咯啉进行氢化和/或对酯的裂解则可以得到适合后续结构修饰的产物,特别是对组合合成有趣的产物。