The solvent free synthesis of six chalcones was carried out by grinding the piperanal and the acetophenone (unsubstituted, 4-methyl, 4-methoxy, 4-bromo, 4-nitro, 3-chloro) in the presence of solid sodium hydroxide with a mortar and pestle. In general, the chalcones were obtained in high yield and high purity. Minor quantities of Ketol and Michael addition product were easily removed by recrystallization. The result indicates a correlation between the success of the solvent-free synthesis and melting point of the chalcone. Chalcone with relatively high melting points (higher than 80°C) were obtained in high yields. The two chalcones that could not be produced in good yields were having relatively low melting points. They have been screened for their antibacterial activity against Gram positive and Gram negative bacteria.

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A series of pyrano­[3,2-c]­quinolone derivatives has been synthesized in the presence of taurine (2-aminoethanesulfonic acid) as a green bio-organic catalyst and water as the solvent. The target compounds were synthesized through the three-component reaction between aldehydes, malononitrile/ethylcyanoacetate, and 4-hydroxy-1-methyl-2­(1H)-quinolone. The advantages of this protocol are excellent yields of products, short reaction times, cost efficiency, atom economy, and a simple work-up procedure with no need for extra purification techniques. Moreover, the catalyst can be easily recovered and reused for up to three cycles without losing any significant activity.

An inexpensive, simple, and greener catalytic system with lower toxicity using CuFe2O4 nanoparticles in the presence of piperidine and dry toluene as a solvent has been reported for the synthesis of 1,4‐diphenylbutadiyne‐1,3, via C−H activated aerobic Csp−Csp homocoupling. This protocol provides 66 % of yield at the gram‐scale level making it appropriate for production at a larger scale. The catalyst shows reusability for up to five cycles without losing any significant catalytic activity.