Reactions of benzyne with several pyridinium N-imines were examined. 2-o-Aminophenylpyridine derivatives 6, pyrido[1,2-b]indazoles (7), indazolo[2,3-a]quinoline (17), and indazolo[3,2-a]isoquinoline (18) were obtained by the reactions of benzyne with the corresponding ylides 5, 10, 15, and 16, respectively.
Synthesis of Pyrido[1,2-<i>b</i>]indazoles via Aryne [3 + 2] Cycloaddition with <i>N</i>-Tosylpyridinium Imides
作者:Jingjing Zhao、Chunrui Wu、Pan Li、Wenying Ai、Hongli Chen、Chaojie Wang、Richard C. Larock、Feng Shi
DOI:10.1021/jo200863e
日期:2011.8.19
The [3 + 2] cycloaddition of arynes with N-tosylpyridinium imides, followed by an elimination of Ts-, affords pyrido[1,2-b]indazoles under mild reaction conditions in good yields.