Alkoxycarbonyl-Substituted 3-Trifloxypropene Iminium Salts and Iminium-Substituted Δ^2,3-Butenolides: Synthesis and Reactivity toward Nucleophiles

Abstract

Triflic anhydride reacts regioselectively with the ethoxy­carbonyl-substituted enaminones 6a-h to give the novel 3-trifloxy­propene iminium salts 7a-d or iminium-substituted Δ^2,3-butenolides 8a-d and 9a-d in good yields. Hydride reduction of the iminium salts 7a,b affords new 2-dialkylamino-4-trifloxy-but-3-enoates 13a,b, while mild hydrolysis generates 2-oxo-4-trifloxy-butenoates 14a,b . Butenolides 8b,d, and 9c react with methyl hydrazine to afford 4-dialkylamino-pyridazin-3(2H)-ones 12a-c.

Key words

iminium salts - sulfonylations - enamines - reductions

References

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