Convenient access to π-conjugated 1,3-azaphospholes from alkynes via [3 + 2]-cycloaddition and reductive aromatization

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

Abstract

When incorporated into π-conjugated systems, phosphorus-based heterocycles have gained significant attention due to their unique chemical and physical properties. However, their syntheses remain challenging. Herein, we describe a novel [3+2]-cycloaddition between 1,3-dipolar triflatophosphanes and alkynes, affording azaphospholium salts. These salts can be reduced to generate the targeted 1,3-azaphospholes and an NHC (N-heterocyclic carbene) byproduct. The reaction is high-yielding, scalable, and can tolerate a wide array of sterically and electronically diverse alkynes, leading to a library of 1,3-azaphospholes (19 examples, up to 99% yield). As a broad range of structural modifications is covered, information on structure-property relationships is extracted from joint experimental and theoretical analysis, revealing efficient strategies for further optimizations. Their high thermal stability and tunable electronic structure render them a promising platform for future applications.

Details

Original languageEnglish
Pages (from-to)644-659
Number of pages16
JournalChem
Volume10
Issue number2
Publication statusPublished - 8 Feb 2024
Peer-reviewedYes

External IDs

ORCID /0000-0002-4112-6991/work/163295279
ORCID /0000-0001-7323-7816/work/163295543

Keywords

Keywords

  • cycloaddition, dipolar, phospholes, phosphorus, photophysics, polyaromatic compounds, SDG9: Industry, innovation, and infrastructure