Ionic liquid catalyzed one-pot synthesis of novel spiro-2-amino-3-phenylsulfonyl-4H-pyran derivatives

A series of novel spiro-2-amino-3-phenylsulfonyl-4H-pyran derivatives were synthesized via the three component, one pot reaction of phenylsulfonylacetonitrile and 1,3-dicarbonyl compounds with isatins or acenaphthenequinone in ethanol with a novel basic ionic liquid 2-hydroxyethyl ammonium acetate [H3N+CH2CH2OH][CH3COO−] (HEAA) as catalyst. HEAA was found to be a suitable and efficient catalyst for this condensation. This method has some distinct advantages such as mild reaction conditions, short reaction time, and environmental friendliness.