Synthesis of Furoxans from Styrenes under Basic or Neutral Conditions

Abstract

Furoxans (1,2,5-oxadiazole 2-oxides) can be synthesized from the corresponding styrenes using NOBF₄ under basic or even almost neutral reaction conditions. Acid-sensitive functional groups are tolerated under the developed basic conditions. For the substrates having poor reactivity, almost neutral conditions (using pyridine equimolar to NOBF₄) are suitable for better yields.

Key words

heterocycles - nitrogen-containing compounds - fur­oxans - styrenes - cyclization

• References

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