Metal-free oxidative coupling of arylmethylamines with indoles: a simple, environmentally benign approach for the synthesis of 3,3'-bis(indolyl)methanes

Vikas D Kadu; Sankala Naga Chandrudu; Mahesh G Hublikar; Dattatraya G Raut; Raghunath B Bhosale

doi:10.1039/d0ra03221b

Metal-free oxidative coupling of arylmethylamines with indoles: a simple, environmentally benign approach for the synthesis of 3,3'-bis(indolyl)methanes

RSC Adv. 2020 Jun 17;10(39):23254-23262. doi: 10.1039/d0ra03221b. eCollection 2020 Jun 16.

Authors

Vikas D Kadu¹, Sankala Naga Chandrudu², Mahesh G Hublikar¹, Dattatraya G Raut¹, Raghunath B Bhosale¹

Affiliations

¹ School of Chemical Sciences, Punyashlok Ahilyadevi Holkar Solapur University Solapur-413255 Maharashtra India vikaskadu1@gmail.com.
² Department of Chemistry, College of Engineering, Rayalseema University Kurnool-518002 Andhra Pradesh India.

Abstract

The efficient metal-free oxidative coupling of arylmethylamines with indoles has been developed using molecular oxygen as a green oxidant. The present reaction provides a novel route towards the synthesis of 3,3'-bis(indolyl)methanes in excellent yields of up to 95% via C-C and C-N bond formation. This attractive and environmentally friendly one-pot protocol is a simple procedure that features inexpensive acetic acid as the catalyst and molecular oxygen as the sole oxidant, and it supports a wide substrate scope with the good tolerance of functional groups.