Synthesis of 3-sulfonyloxypyridines: Oxidative ring expansion of α-furylsulfonamides and N→ O sulfonyl transfer

R Hodgson, A Kennedy, A Nelson, A Perry

Index: Hodgson, Robert; Kennedy, Andrew; Nelson, Adam; Perry, Alexis Synlett, 2007 , # 7 p. 1043 - 1046

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Citation Number: 6

Abstract

Treatment of the sulfonamide 9a with MCPBA or NBS gave the pyridinone 10a in 99% yield (Scheme [4] ). Previous aromatisations of pyridinones have used acid catalysis to promote dehydration and, hence, aromatisation. [9] [10] We investigated the aromatisation of the pyridinone 10a in the presence of a range of Lewis acids (Scheme [4] ); selected examples are described in Table [2] . The yield of the pyridine 11a increased with the strength of the Lewis acid (for ...