TY - JOUR
T1 - Functionalized α-oximinoketones as building blocks for the construction of imidazoline-based potential chiral auxiliaries
AU - Gutiérrez, Rsuini U.
AU - Rebollar, Araceli
AU - Bautista, Rafael
AU - Pelayo, Vanessa
AU - Várgas, José Luis
AU - Montenegro, Mabel M.
AU - Espinoza-Hicks, Carlos
AU - Ayala, Francisco
AU - Bernal, Pablo M.
AU - Carrasco, Cuauhtemoc
AU - Zepeda, L. Gerardo
AU - Delgado, Francisco
AU - Tamariz, Joaquín
N1 - Publisher Copyright:
©2015 Elsevier Ltd. All rights reserved.
PY - 2015/2/28
Y1 - 2015/2/28
N2 - Functionalized α-oximinoketones with β-alkoxy, β-alkyl, and β-sulfenyl groups were used as efficient synthons for the preparation of chiral 1-acyl-4-imidazolin-2-ones and 1-acylimidazolidin-2-ones. For the preparation of the former heterocycles, α-oximinoketones were transformed into their respective imidazole N-oxides by neutral treatment with a chiral triazine, followed by reaction with acetic or propionic anhydrides to furnish the desired chiral 1-acetyl- or 1-propionyl-4-imidazolin-2-ones in moderate overall yields. Upon palladium hydroxide-catalyzed hydrogenation, these series were converted into their corresponding 1-acylimidazolidin-2-ones in high diastereoisomeric ratios. Thus, these novel chiral 1-acetyl- and 1-propionyl-imidazolidin-2-ones were obtained with a variety of alkyl groups at the C-4 and C-5 positions of the heterocycle, through a three-step methodology, and can be applied as new potential chiral auxiliaries.
AB - Functionalized α-oximinoketones with β-alkoxy, β-alkyl, and β-sulfenyl groups were used as efficient synthons for the preparation of chiral 1-acyl-4-imidazolin-2-ones and 1-acylimidazolidin-2-ones. For the preparation of the former heterocycles, α-oximinoketones were transformed into their respective imidazole N-oxides by neutral treatment with a chiral triazine, followed by reaction with acetic or propionic anhydrides to furnish the desired chiral 1-acetyl- or 1-propionyl-4-imidazolin-2-ones in moderate overall yields. Upon palladium hydroxide-catalyzed hydrogenation, these series were converted into their corresponding 1-acylimidazolidin-2-ones in high diastereoisomeric ratios. Thus, these novel chiral 1-acetyl- and 1-propionyl-imidazolidin-2-ones were obtained with a variety of alkyl groups at the C-4 and C-5 positions of the heterocycle, through a three-step methodology, and can be applied as new potential chiral auxiliaries.
UR - http://www.scopus.com/inward/record.url?scp=84922828011&partnerID=8YFLogxK
U2 - 10.1016/j.tetasy.2015.01.011
DO - 10.1016/j.tetasy.2015.01.011
M3 - Artículo
SN - 0957-4166
VL - 26
SP - 230
EP - 246
JO - Tetrahedron Asymmetry
JF - Tetrahedron Asymmetry
IS - 4
ER -