Synlett 2023; 34(02): 101-105
DOI: 10.1055/a-1934-1254
synpacts

Reactions of Nitroarenes with Corey–Chaykovsky Reagents

Damian Antoniak
,
Authors thank the OPUS 16 program of the Narodowe Centrum Nauki (National Science Centre), Poland (UMO-2018/31/B/ST5/01118) for support, while writing this manuscript.


Abstract

Electrophilic and nucleophilic substitutions of aromatic substrates share common mechanistic pathways. In both scenarios reacting species attack rings at the unsubstituted (C–H) positions, giving cationic Wheland intermediates or anionic Meisenheimer complexes. However, the following step of rearomatization breaks the intrinsic symmetry, due to different leaving group ability of proton and hydride anion, respectively. In effect, electron-deficient arenes are prone to transformations unparalleled in electrophilic chemistry. In our article, we present transformations of anionic σH-adducts, formed between nitroarenes and carbanions of the Corey–Chaykovsky reagents. Depending on structure of the substrates and reaction conditions, the intermediates undergo cyclization to cyclopropanes (norcaradienes) or base-induced elimination to the alkylated products. Mechanistic studies reveal that order of the carbanions controls competition between the processes, due to steric hindrance developing at the β-elimination step.

1 Introduction

2 Cyclopropanation of Nitronaphthalenes

3 Alkylation of Nitropyridines

4 Mechanistic Studies

5 Summary and Outlook



Publication History

Received: 03 August 2022

Accepted after revision: 30 August 2022

Accepted Manuscript online:
31 August 2022

Article published online:
12 October 2022

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