This script written by William Reusch, Dept. of Chemistry, Michigan State University. Please send comments and corrections to [email protected] The Mechanism of Enamine Formation The Mechanism of Enamine Formation The Mechanism of Enamine Formation The Mechanism of Enamine Formation The Mechanism of Enamine Formation The Mechanism of Enamine …

2009年10月31日 · This concept has been successfully applied to : Asymmetric Aldol Reactions Asymmetric Michael Reactions Asymmetric Mannich Reactions Asymmetric α-Functionalization of Carbonyl Compounds Asymmetric γ-Functionalization of Carbonyl Compounds

The double bond of the enamine transmits the nucleophilic character of the nitrogen to the alpha-carbon, in a vinylagous fashion. Because of the resulting ambident nucleophilicity of the enamines, reactions with electrophiles may take place at either nitrogen or carbon.

23.12 The Stork Enamine Reaction Michael rxn with an enamine nucleophile instead of an enolate: protonates the enolate and hydrolyzes the iminium

D. Enamine Formation The previous reactions have all involved reagents of the type: Y–NH2, i.e. reactions with a 1º-amino group. Most aldehydes and ketones also react with 2º-amines to give products known as enamines. Two examples of these …

18 Heating cyclopentanone with either: I ethyl amine, or II diethylamine, together with an acid catalyst leads to different results. Which of the following best describes this difference? A) I gives an imine & II fails to react B) I gives an enamine & II fails to react C) I gives an imine & II gives an enamine D) I gives an enamine & II gives ...

The most basic site in the reactants is the pyrrolidine nitrogen atom. Its conjugate acid is shown on the left above. This "onium" ion will be in equilibrium with many other conjugate acid species, one of which is drawn on the right. Equilibria of this kind always favor the weaker acid and base. Since the tetravalent nitrogen in the "onium" ion cannot form additional bonds, this species is ...

The imine or enamine intermediates are normally not isolated, but are immediately reduced to the amine product. To see an animated mechanism for imine formation

2007年5月18日 · Enamine/Iminium catalysis: Highlights from the evolution of pyrolidine-type catalysts HX HX PART 1: ENAMINE CATALYSIS Lessons from nature: Aldolases catalyzed aldol reaction FDP Aldolase vs antibody aldolase Antibody …

If water had been the solvent, the resulting 1º-enamine would have rearranged to an imine and hydrolyzed to an aldehyde. In the Lossen rearrangement (# 7) butyl amine adds to the isocyanate to give a substituted urea (urea is NH 2 CONH 2).