Ketalization of Ketones to 1,3-Dioxolanes and Concurring Self-Aldolization Catalyzed by an Amorphous, Hydrophilic SiO2-SO3H Catalyst under Microwave Irradiation

• Autor(a) principal: Barbosa,Sandro L.
• Data de Publicação: 2018
• Outros Autores: Ottone,Myrlene, Almeida,Mainara T. de, Lage,Guilherme L. C., Almeida,Melina A. R., Nelson,David Lee, Santos,Wallans T. P. dos, Clososki,Giuliano C., Lopes,Norberto P., Klein,Stanlei I., Zanatta,Lucas D.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Journal of the Brazilian Chemical Society (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532018000801663
• topic: protonated ketones; self-aldolization; ketalization; ketal hydrolysis; sulfonated silica

The amorphous, mesoporous SiO2-SO3H catalyst with a surface area of 115 m2 g-1 and 1.32 mmol H+ per g was very efficient for the protonation of ketones on a 10% (m/m) basis, and the catalyst-bound intermediates can be trapped by polyalcohols to produce ketals in high yields or suffer aldol condensations within minutes under low-power microwave irradiation. The same catalyst can easily reverse the ketalization reaction.