Gas-phase generation and cyclisation reactions of imidoyl radicals.

Org Biomol Chem

Dipartimento di Chimica Organica A. Mangini, Università di Bologna, Viale Risorgimento 4, I-40136, Bologna, Italy.

Published: January 2012

Some 1,2-diarylimidoyl radicals were generated in the gas-phase by intramolecular radical translocation from ortho-imino-aryloxyl radicals, in turn generated under flash vacuum pyrolysis (FVP) conditions. The imidoyls reacted with XR ortho'-substituents in the N-aryl group to give (in most cases) modest yields of cyclisation products. Depending on the nature of the bridging atom (X), the formation of these products was initiated either by a further hydrogen atom translocation (X = CH(2)), or by ipso-attack onto the aryl group (R = Ph), or by direct substitution at the heteroatom (X = S). With XR = N(Me)Ph, the major reaction product was probably the result of a competing pathway not involving the corresponding imidoyl.

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http://dx.doi.org/10.1039/c1ob06228jDOI Listing

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