Katta Venkateswarlu

Simple Catalyst-Free Regio- and Chemoselective Monobromination of Aromatics Using NBS in Polyethylene Glycol

Abstract NBS in polyethylene glycol has been efficiently utilized for regio- and chemoselective bromination of activated aromatics at room temperature to form the corresponding bromo products in excellent yields.

Synthesis of pyrano and furanoquinolines using silica chloride or amberlyst-15 as a heterogeneous catalyst

The coupling of three components, anilines, benzaldehydes and 3,4-dihydro-2H- pyran or 2,3-dihydrofuran to prepare the corresponding pyrano or furanoquinolines has been achieved efficiently using silica chloride or Amberlyst-15 as a heterogeneous catalyst. Amberlyst-15 can be recovered and reused.

Synthesis of coumarins via a Pechmann condensation using heterogeneous catalysts

The synthesis of coumarins via a Pechmann condensation involving the reaction between phenols and ethyl acetoacetate has been carried out using two heterogeneous catalysts, NaHSO4.SiO2 and silica chloride under solvent free conditions, thus avoiding acidic waste