Sulfuric Acid-modified PEG-6000 (PEG-SO3H): An Efficient, Bio-degradable and Reusable Catalyst for Synthesis of α, α´ bis(arylidene) Cycloalkanones Under Solvent-free Conditions

A green and efficient method for synthesis of α,α´ -bis (arylidene) cycloalkanones, starting from aromatic aldehydes in reaction with ketones using sulfonated polyethylene glycol 6000 (PEG-SO3H) as a stable, reusable and biodegradable catalyst under solvent-free conditions at 80 °C is described. The use of a nontoxic, inexpensive, easily available and recyclable catalyst makes this protocol practical, environmentally friendly and economically attractive.