The Dynamic Lewis Acid-Carbene Hybrid: Pushing the Electrophilicity of Carbenes to the Limit

Runbo Pei; Liancheng He; Yue Zhao; Xinping Wang

doi:10.1021/jacs.3c07923

The Dynamic Lewis Acid-Carbene Hybrid: Pushing the Electrophilicity of Carbenes to the Limit

J Am Chem Soc. 2023 Oct 11;145(40):21733-21737. doi: 10.1021/jacs.3c07923. Epub 2023 Sep 29.

Authors

Runbo Pei¹, Liancheng He¹, Yue Zhao¹, Xinping Wang^{1

2}

Affiliations

¹ State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
² State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China.

PMID: 37774109
DOI: 10.1021/jacs.3c07923

Abstract

This work describes a Lewis-acid-coordination strategy to efficiently enhance the electrophilicity of a carbene beyond structural modification. A hybrid BCF-DAC is formed by the coordination of a Lewis acid, B(C₆F₅)₃ (BCF), to an N,N'-diamidocarbene (DAC), possessing superior low LUMO energy that is indicated by theoretical calculation. This endows the hybridized carbene with a unique reactivity that speeds up the activation of the sp³-hybridized C-H bond of toluene and the [2+1] cycloaddition with C₂H₂. More strikingly, the hybrid readily undergoes [2+1] cycloaddition with C₂H₄ under ambient conditions, which is the first example of a stable carbene reacting with ethylene. The Lewis acid approach also features dynamic behavior and electrophilicity tunability.