Efficient synthesis of trifluoromethylated dihydrochalcones, aryl vinyl ketones and indanones by superelectrophilic activation of 4,4,4-trifluoro/3-(trifluoromethyl)crotonic acids

Superacid catalyzed electrophilic substitution of arenes using 4,4,4,-trifluoro/3-trifluoromethylcrotonic acids has been investigated. The direct synthesis of various trifluoromethylated dihydrochalcones, aryl vinyl ketones and indanones has been achieved by this methodology. It has been found that the position of the trifluoromethyl group has a profound effect on the nature of the reaction and the products. In the pharmaceutical industry, many fluoroorganics are shown to possess significant biological and therapeutic activities. Therefore, these novel compounds can be considered key intermediates for the preparation of potential biologically active molecules.

Graphical abstractDirect synthesis of trifluoromethylated dihydrochalcones, aryl vinyl ketones, and indanones has been achieved by superelectrophilic activation of 4,4,4-trifluoro/3-(trifluoromethyl)crotonic acids followed by Friedel–Crafts alkylation/acylation/cyclalkylation in excess triflic acid.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Superacid catalyzed electrophilic substitution of arenes using 4,4,4,-trifluoro/3-trifluoromethylcrotonic acids has been investigated. ► Synthesis of various trifluoromethylated dihydrochalcones, aryl vinyl ketones and indanones has been achieved. ► Position of the trifluoromethyl group seems to have profound effect on the nature of the reaction and the products. ► Mechanistic aspects have been supported by ab initio calculations.