Sonochemical cycloadditions in ionic liquids. Lessons from model cases involving common dienes and carbonyl
José Luis Bravo1, Ignacio López, Pedro Cintas
1Departamento de Química Orgánica, Universidad de Extremadura, Cáceres E-10071, Spain. jlbravo@unex.es
Abstract:
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.
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