Synthesis 2024; 56(15): 2385-2391
DOI: 10.1055/a-2288-6944
paper
Special Issue PSRC-10 (10th Pacific Symposium on Radical Chemistry)

A Photochemical Strategy for the Synthesis of Caprolactams via Dearomative Ring Expansion of Nitroarenes

a   Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
,
Linda Bui
b   Institute of Organic Chemistry, RWTH Aachen University, 52056 Aachen, Germany
,
Vincent K. Duong
a   Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
,
Alessandro Ruffoni
b   Institute of Organic Chemistry, RWTH Aachen University, 52056 Aachen, Germany
,
Daniele Leonori
b   Institute of Organic Chemistry, RWTH Aachen University, 52056 Aachen, Germany
› Author Affiliations
R.S.-B. thanks the European Union Horizon 2020 innovation programme for a Marie Skłodowska-Curie grant, agreement no. 956324 (PhotoReAct).


Abstract

This paper outlines a novel strategy for the preparation of seven-membered-ring lactams from simple nitroarenes. The approach is based on a photochemical dearomative ring expansion starting with the conversion of the nitro group into a singlet nitrene. This process is mediated by blue light, occurs at room temperature and overall enables the insertion of the nitro N-atom into the benzenoid framework. This step transforms the aromatic starting material into a seven-membered ring azepine that, following hydrogenation and hydrolysis, is converted into the desired caprolactams in just three steps.

Supporting Information



Publication History

Received: 15 February 2024

Accepted after revision: 15 March 2024

Accepted Manuscript online:
15 March 2024

Article published online:
02 April 2024

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