Palladium-Catalyzed Heck Cyclization with P(O)H Compounds to Construct Phosphinonyl-Azaindoline and -Azaoxindole Derivatives.

We report herein a concise method for the construction of phosphinonyl-azaindoline and -azaoxindole derivatives via a palladium-catalyzed cascade cyclization with P(O)H compounds. Various H -phosphonates, H -phosphinates, and aromatic secondary phosphine oxides are all tolerated under the reaction conditions. Furthermore, the phosphinonyl-azaindoline isomer families such as 7-, 5-, and 4-azaindolines could be synthesized in moderate to good yields.