Unprecedented Reactivity of γ-Amino Cyclopentenone Enables Diversity-Oriented Access to Functionalized Indoles and Indole-Annulated Ring Structures

Chenna Jagadeesh; Biplab Mondal; Sourav Pramanik; Dinabandhu Das; Jaideep Saha

doi:10.1002/anie.202016015

Unprecedented Reactivity of γ-Amino Cyclopentenone Enables Diversity-Oriented Access to Functionalized Indoles and Indole-Annulated Ring Structures

Angew Chem Int Ed Engl. 2021 Apr 12;60(16):8808-8812. doi: 10.1002/anie.202016015. Epub 2021 Mar 10.

Authors

Chenna Jagadeesh¹, Biplab Mondal¹, Sourav Pramanik¹, Dinabandhu Das², Jaideep Saha¹

Affiliations

¹ Division of Molecular Synthesis & Drug Discovery, Centre of Biomedical Research (CBMR), SGPGIMS Campus, Raebareli Road, Lucknow, 226014, Uttar Pradesh, India.
² School of Physical Sciences, Jawaharlal Nehru University, New Delhi, India.

PMID: 33527571
DOI: 10.1002/anie.202016015

Abstract

Observation of an unexpected, Lewis acid promoted displacement of latent reactive γ-amino group on cyclopentenone presented unparalleled opportunity for enone functionalization and annulations with indole derivatives, which is developed in the current study. Herein, a vast range of C3/N-indolyl enones and indole alkaloid-like compound were accessed in excellent yields (up to 99 %) and selectivity through a one-pot operation. The mechanism most likely involves an unprecedented trait of Piancatelli-type rearrangement where influence of the gem-diaryl group appeared crucial.

Keywords: Lewis acids; annulation; aza-Piancatelli reaction; enone functionalization; indole alkaloids.

Publication types

Research Support, Non-U.S. Gov't