Investigation of proline derivatives for the efficient organocatalysis of an Aldol type reaction in supercritical CO2

Investigation of proline derivatives for the efficient organocatalysis of an Aldol type reaction in supercritical CO2

Cassaro, R. F.; Sakae, G.; Takata, L.M.; Santos, A. dos; Gariani, R. A.; Bazito, R. C.

Abstract:

The search for organocatalysts, i.e., small chiral molecules that are able to act as catalysts in enantioselective transformations, has received extensive attention, because of the potential for savings in cost, time and energy, easier experimental procedures, and reductions in chemical waste. The aldol reaction is one of the most widely used reactions for C–C bond formation yet it has several drawbacks from an environmental standpoint, and this makes it an ideal candidate for organocatalysis. The use of supercritical carbon dioxide (sc-CO2) as a solvent for this reaction has been investigated. Sc-CO2, is considered an environmentally benign solvent with an accessible critical point (Tc = 304.2 K, Pc = 7.38 MPa), and excellent transport properties. Our group has recently studied a series of proline derivatives for the organocatalysis of Aldol type reactions in sc-CO2. In this work, we continue this investigation using proline, a proline based helical polymer and a silane proline derivative to study the behavior of a model Aldol reaction using a cyclic ketone in sc-CO2 (Scheme 1).

The search for organocatalysts, i.e., small chiral molecules that are able to act as catalysts in enantioselective transformations, has received extensive attention, because of the potential for savings in cost, time and energy, easier experimental procedures, and reductions in chemical waste. The aldol reaction is one of the most widely used reactions for C–C bond formation yet it has several drawbacks from an environmental standpoint, and this makes it an ideal candidate for organocatalysis. The use of supercritical carbon dioxide (sc-CO2) as a solvent for this reaction has been investigated. Sc-CO2, is considered an environmentally benign solvent with an accessible critical point (Tc = 304.2 K, Pc = 7.38 MPa), and excellent transport properties. Our group has recently studied a series of proline derivatives for the organocatalysis of Aldol type reactions in sc-CO2. In this work, we continue this investigation using proline, a proline based helical polymer and a silane proline derivative to study the behavior of a model Aldol reaction using a cyclic ketone in sc-CO2 (Scheme 1).

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DOI: 10.5151/chempro-15bmos-BMOS2013_201382017856

Referências bibliográficas

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Como citar:

Cassaro, R. F.; Sakae, G.; Takata, L.M.; Santos, A. dos; Gariani, R. A.; Bazito, R. C.; "Investigation of proline derivatives for the efficient organocatalysis of an Aldol type reaction in supercritical CO2", p-55-55. In: In Blucher Chemistry Proceedings, São Paulo, v. 1, n. 2, Dezembro.2013. São Paulo: Blucher, 2013.
ISSN 23184043, DOI 10.5151/chempro-15bmos-BMOS2013_201382017856