A novel and eco-friendly method for Synthesis of 3-benzylidene-2-phenyl chroman-4-one analogs

The main aim of present work was to develop eco-friendly and green method for synthesis of 3-benzylidene-2- phenylchroman-4-one derivatives. For the synthesis of 3-benzylidene-2-phenylchroman-4-one derivatives variety of acid and base catalyzed methods was performed. HCl gas and p-TSA proved ineffective as catalyst. Concentrated HCl in n-butanol was very less effective method. Upon taking base catalyst, by product was formed when taking NaOH as catalyst and very low yield obtained using piperidine as catalyst. To overcome this problem, novel and eco-friendly method was developed in which barium hydroxide used as a base catalyst. In presence of ethanol product yield drastically increased. Main benefit of this method is reaction carried out by gradual trituration and very less amount of solvent was required. By using this method, product obtained in very high yield with more purity.