RT info:eu-repo/semantics/article
T1 Enantioselective amination of 4-substituted pyrazolones catalyzed by oxindole-containing thioureas and by a recyclable linear-polymer-supported analogue in a continuous flow process
A1 Sánchez Molpeceres, Rodrigo
A1 Martín Maroto, Laura
A1 Esteban Hernández, Isabel Noelia
A1 Miguel García, Jesús Ángel
A1 Maestro Fernández, Alicia
A1 Andrés García, José María
K1 Química orgánica
K1 Polimeros y polimerización
K1 Aromatic compounds
K1 Catalysts
K1 Mixtures
K1 Compuestos aromáticos
K1 Catalizadores
K1 Mezclas
K1 2306 Química Orgánica
AB A highly efficient organocatalytic amination of 4-substituted pyrazolones with azodicarboxylates mediated by a novel quinine-derived thiourea with a 3,3-diaryl-oxindole scaffold is reported. This synthetic method furnished 4-amino-5-pyrazolones in high yields and with excellent enantioselectivities (up to 97:3 er) at room temperature in short reaction times. Moreover, a linear-polymer-supported bifunctional thiourea, synthesized by reacting a bifunctional aromatic monomer (biphenyl) with isatin in superacidic media and further derivatization, was proven to be also an efficient heterogeneous organocatalyst for this α-amination reaction. The practical value of this process was demonstrated by the use of the immobilized catalyst in recycling experiments, maintaining the activity without additional reactivation, and in flow processes, allowing the synthesis of 4-amino-pyrazolone derivatives in a gram scale with high yield and enantioselectivity.
PB American Chemical Society
SN 0022-3263
YR 2023
FD 2023
LK https://uvadoc.uva.es/handle/10324/63800
UL https://uvadoc.uva.es/handle/10324/63800
LA eng
NO The Journal Of Organic Chemistry, 2024, vol. 89, n.1, pp. 330-344
NO Producción Científica
DS UVaDOC
RD 21-dic-2024