One-pot three-component synthesis of tetrahydrobenzo[b]pyran derivatives using silica-bonded ionic liquid as recyclable catalyst

Tetrahydrobenzo[b]pyran derivatives were synthesized in the presence of silicapropyl-caffeine hydrogen sulfate ([Sipcaf]HSO4) as a recyclable solid acid catalyst from the reaction between aldehydes, malononitrile, and 1,3-cyclohexanedione or 5,5- dimethyl-1,3-cyclohexanedione at 100 ºC under solvent-free conditions.

Keywords:

Tetrahydrobenzo[b]pyran , silicapropyl-caffeine hydrogen sulfate ([Sipcaf] HSO4) , Solvent-free