A Catalyst-Free Benzylic C–H Bond Olefination of Azaarenes for Direct Mannich-like Reactions

A highly efficient synthesis of trans-alkenylazaarene under catalyst-free conditions was developed via the addition of methylazaarenes to N-sulfonyl aldimines and a subsequent C–N elimination in situ. A one-pot procedure for this addition–elimination was also developed. The reaction could tolerate a broad substrate scope and give the corresponding alkenylazaarenes in high yields.

本研究开发了一种无催化条件下高效合成反式烯基氮杂芳烃（trans-alkenylazaarene）的方法，该方法通过将甲基氮杂芳烃（methylazaarenes）加成至N-磺酰基亚胺（N-sulfonyl aldimines），并经后续原位C-N消除反应得以实现。同时，本研究还开发了该加成-消除过程的一锅法（one-pot procedure）操作流程。该反应具有宽泛的底物适用范围，能够以高产率得到相应的烯基氮杂芳烃产物。