Abstract

The present manuscript deals with the effectiveness of mineral, LiNTf₂ supported and ionic liquid, 3-methyl-1-octyl-imidazolium tetrachloroaluminate mediated Diels-Alder reactions of isoprene with maleic acid and 2-cyclohexene-1-one in conventional and microwave techniques. The Diels- Alder reactions of isoprene with maleic acid and 2-cyclohexene-1-one proceeded efficiently and smoothly in the presence of the minerals to provide the Diels-Alder adduct in moderate to excellent yields at various reaction conditions. A promising advantage of this green method is that the entire ionic liquid/LiNTf2 system can be recovered and reprocessed up to five runs without an appreciable loss of activity. The solid support LiNTf2 possesses commanding mechanical features that increased the catalytic efficiency in polar ionic liquid.

Keywords: Isoprene, maleic acid, 2-cyclohexene-1-one, diels-alder reaction, ionic liquid, LiNTf2, microwave, solid supports.

Graphical Abstract