Synthesis 2020; 52(04): 574-580
DOI: 10.1055/s-0039-1690048
© Georg Thieme Verlag Stuttgart · New York

Highly Efficient Synthesis of Hindered 3-Azoindoles via Metal-Free C–H Functionalization of Indoles

Nicolas Jacob
Lucas Guillemard
Joanna Wencel-Delord
Laboratoire d’Innovation Moléculaire et Applications (UMR CNRS 7042), Université de Strasbourg/Université de Haute-Alsace, ECPM, 25 Rue Becquerel, 67087 Strasbourg, France   Email: [email protected]
› Author Affiliations
This work was carried out within ANR JCJC grant ‘2al-Vis-Phot-CH’ (ANR-15-CE29-0004-01).
Further Information

Publication History

Received: 20 November 2019

Accepted after revision: 06 January 2020

Publication Date:
16 January 2020 (online)

Published as part of the Bürgenstock Special Section 2019 Future Stars in Organic Chemistry


Although 3-azoindoles have recently emerged as an appealing family of photoswitch molecules, the synthesis of such compounds has been poorly covered in the literature. Herein a high-yielding and operationally simple protocol is reported allowing the synthesis of 3-azoindoles, featuring important steric hindrance around the azo motif. Remarkably, this C–H coupling is characterized by excellent atom economy and occurs under metal-free conditions, at room temperature, and within few minutes, delivering the expected products in excellent yields (quantitatively in most of the cases). Accordingly, a library of new molecules, with potential applications as photochromic compounds, is prepared.

Supporting Information

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