Sonochemical cycloadditions in ionic liquids. Lessons from model cases involving common dienes and carbonyl dienophiles.
This contribution describes a series of sonochemical cycloadditions involving either cyclopentadiene or 1,3-cyclohexadiene with carbonyl dienophiles in an imidazolium-based ionic liquid as reaction medium. In general, ultrasound does effectively improve these processes in terms of higher yields and/or shorter reaction times when compared with the corresponding silent reactions. Stereoselectivities, however, remain practically unaffected by sonication. The role of ionic liquids under ultrasonic activation is also discussed.
Bravo
José Luis
JL
Departamento de Química Orgánica, Universidad de Extremadura, Cáceres E-10071, Spain. jlbravo@unex.es
López
Ignacio
I
Cintas
Pedro
P
Silvero
Guadalupe
G
Arévalo
María José
MJ
D002621:Chemistry / Q000379:methods*; D002855:Chromatography, Thin Layer; D003510:Cyclohexanes / Q000737:chemistry*; D053138:Cyclohexenes; D003517:Cyclopentanes / Q000737:chemistry*; D007477:Ions; D009682:Magnetic Resonance Spectroscopy; D008956:Models, Chemical; D012997:Solvents / Q000737:chemistry; D013010:Sonication; D013696:Temperature; D014465:Ultrasonics
D003510:Cyclohexanes; D053138:Cyclohexenes; D003517:Cyclopentanes; D007477:Ions; D012997:Solvents; C034005:1,3-cyclohexadiene