103818-68-4Relevant academic research and scientific papers
Synthetic applications of the β-lithiation of β-Aryl secondary amides: Diastereoselective and enantioselective substitutions
Lutz, Gary P.,Du, Hua,Gallagher, Donald J.,Beak, Peter
, p. 4542 - 4554 (2007/10/03)
The sequence of β-lithiation and electrophilic substitution of β-aryl secondary amides is reported. The lithiations occur regioselectively at the β-position, and the resulting lithiated intermediates can be reacted with a wide range of electrophiles to give substituted products. Reactions of β-lithiated amides bearing an α-substituent provide substituted products with high diastereoselectivity. Electrophilic substitutions of β-lithiated N-methylamides in the presence of the chiral diamine (-)-sparteine provide highly enantioenriched products. The methodology is used to synthesize enantioenriched β-aryl β-substituted amides, acids, and lactones.
The Favorskii Rearrangement of α-Chloro Ketimines
Kimpe, Norbert De,Sulmon, Paul,Moeens, Luc,Schamp, Niceas,Declercq, Jean-Paul,Meerssche, Maurice Van
, p. 3839 - 3848 (2007/10/02)
The Favorskii rearrangement of α-chloro ketimines has been studied.It was shown that the base-induced rearrangement of α-chloro ketimines afforded imidates or amides via a mechanism involving 1,3-dehydrochlorination and ring-opening of the resulting cyclopropylideneamines.The ring-opening occurred in such a way as to produce the most stable carbanion.The entire mechanism paralleled the well-known cyclopropanone mechanism of the Favorskii rearrangement of the corresponding oxygen analogues, i.e., α-halo ketones.Evidence has been presented that the semibenzilic-type mechanism is not operative in the cases studied.Depending upon the reaction conditions and the substrate, the Favorskii rearrangement was accompanied by various side reactions including nucleophilic substitution, 1,2-dehydrochlorination, rearrangement via intermediate α-alkoxyaziridines, and self-condensation.
