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Cycloadditions of 1,2,3-Triazines Bearing C5-Electron Donating Substituents: Robust Pyrimidine Synthesis.

ABSTRACT: The examination of the cycloaddition reactions of 1,2,3-triazines 17-19, bearing electron-donating substituents at C5, are described. Despite the noncomplementary 1,2,3-triazine C5 substituents, amidines were found to undergo a powerful cycloaddition to provide 2,5-disubstituted pyrimidines in excellent yields (42-99%; EDG = SMe > OMe > NHAc). Even select ynamines and enamines were capable of cycloadditions with 17, but not 18 or 19, to provide trisubstituted pyridines in modest yields (37-40% and 33% respectively).

SUBMITTER: Glinkerman CM

PROVIDER: S-EPMC4546508 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Cycloadditions of 1,2,3-Triazines Bearing C5-Electron Donating Substituents: Robust Pyrimidine Synthesis.

Glinkerman Christopher M CM Boger Dale L DL

Organic letters 20150714 16

The examination of the cycloaddition reactions of 1,2,3-triazines 17-19, bearing electron-donating substituents at C5, are described. Despite the noncomplementary 1,2,3-triazine C5 substituents, amidines were found to undergo a powerful cycloaddition to provide 2,5-disubstituted pyrimidines in excellent yields (42-99%; EDG = SMe > OMe > NHAc). Even select ynamines and enamines were capable of cycloadditions with 17, but not 18 or 19, to provide trisubstituted pyridines in modest yields (37-40% a ...[more]

PMID: 26172042

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