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DOI: 10.1039/A907656E (Paper) Reference Section for: J. Chem. Soc., Perkin Trans. 1, 1999, 3565-3567

Ring contraction of dihydro-1,3-thiazines to pyrroles on cyclisation

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Gareth M. Davies, Richard W. McCabe and Douglas W. Young

Abstract

Dihydrothiazines such as 8 and 12, which are disubstituted at C-7, undergo an interesting cyclisation–ring contraction reaction with substituted acrylic acids yielding the pyrroles 9 and 13 respectively. This contrasts with the corresponding reaction of thiazines 2 which are monosubstituted at C-7 which undergo a simple cyclisation reaction. A mechanism is suggested for the cyclisation–ring contraction process.

References

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