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DOI: 10.1039/A800884A (Paper) Reference Section for: J. Chem. Soc., Perkin Trans. 1, 1998, 1825-1832

A study of the gas-phase interconversion of 1-(2-aryloxyphenyl)alkaniminyl and 2-(aryliminomethyl)phenoxyl radicals

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Michael Black, J. I. G. Cadogan, Rino Leardini, Hamish McNab, Graham McDougald, Daniele Nanni, David Reed and Alberto Zompatori

Abstract

Flash vacuum pyrolysis of the allyl ethers 9–11 and of the oxime ethers 15–17 at 650 °C (5 × 10–2–5 × 10–3 Torr) generates 2-(aryliminomethyl)phenoxyl radicals 4 and 1-(2-aryloxyphenyl)alkaniminyl radicals 5 respectively which can interconvert via a spirodienyl radical leading to common products which are generally isolated in low to moderate yield. The iminyls 5 normally undergo β-cleavage leading to nitriles (e.g. 21) and/or to benzofurans (e.g. 22) after cyclisation. The phenoxyls 4 show more complex behaviour dominated by hydrogen abstraction processes leading to products such as phenols (e.g. 32), the indole 27 or phenanthridines 34 and 35.

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