B(C6F5)3-Catalyzed Synthesis of 3,3′-Bisindolylmethane Derivatives

Herein, we report a simple and direct protocol for preparing the 3, 3'-bisindolylmethane derivatives with indoles and aryl aldehydes as the substrates via a B (C6F5),-catalyzed process of dehydration. The model reaction was detected with full conversion in 15 min. The scope of the substrates is broad and kinds of functional groups are tolerant as well. In this work, the strategy of efficient synthesis of 3, 3'-bisindolylmethane derivatives was developed under mild and transition-metal-free conditions with water as the sole by-product, which conduced to achieve the quirk synthesis of the target products.