Synthesis and Intramolecular Azo Coupling of 4-Diazopyrrole-2-carboxylates: Selective Approach to Benzo and Hetero [<i>c</i>]-Fused 6<i>H</i>-Pyrrolo[3,4-<i>c</i>]pyridazine-5-carboxylates
作者:Ekaterina E. Galenko、Alexey V. Galenko、Alexander F. Khlebnikov、Mikhail S. Novikov、Julia R. Shakirova
DOI:10.1021/acs.joc.6b01662
日期:2016.9.16
of fluorescent benzo, thieno, and furo [c]-fused methyl 7-aryl-6H-pyrrolo[3,4-c]pyridazine-5-carboxylates, including unprecedented heterocyclic skeletons, was performed by the transformation of methyl 4-aminopyrrole-2-carboxylate into the corresponding diazo compound, followed by intramolecular azo coupling under acid conditions onto a nucleophilic aryl or hetaryl group in the 3-position. Azo coupling
荧光苯并,噻吩并与呋喃并[ c ]稠合的甲基7-芳基-6 H-吡咯并[3,4- c ]哒嗪-5-羧酸酯的合成,包括空前的杂环骨架,都可以通过高转化率合成将4-氨基吡咯-2-羧酸甲酯合成相应的重氮化合物,然后在酸性条件下将分子内偶氮偶合到3-位的亲核芳基或杂芳基上。偶氮偶联是完全区域选择性的,并且根据DFT计算,是动力学控制的反应。1,3-二取代的2 H-吡咯并[3,4- c ] cinnolines的N-甲基化在动力学控制下在N5选择性地发生,仅导致5-methyl-5 H-pyrrolo [3,4- c ] cinnoline衍生物。