18494-53-6Relevant academic research and scientific papers
Catalytic transamidation reactions compatible with tertiary amide metathesis under ambient conditions
Stephenson, Nickeisha A.,Zhu, Jiang,Gellman, Samuel H.,Stahl, Shannon S.
experimental part, p. 10003 - 10008 (2009/12/08)
The carbon-nitrogen bond of carboxamides is extremely stable under most conditions. The present study reveals that simple zirconium- and hafnium-amido complexes are highly efficient catalysts for equilibrium-controlled transamidation reactions between sec
Discovery and mechanistic study of AlIII-catalyzed transamidation of tertiary amides
Hoerter, Justin M.,Otte, Karin M.,Gellman, Samuel H.,Cui, Qiang,Stahl, Shannon S.
, p. 647 - 654 (2008/10/09)
Cleavage of the C-N bond of carboxamides generally requires harsh conditions. This study reveals that tris(amido)AlIII catalysts, such as Al2(NMe2)6, promote facile equilibrium-controlled transamidation of tertiary carboxamides with secondary amines. The mechanism of these reactions was investigated by kinetic, spectroscopic, and density functional theory (DFT) computational methods. The catalyst resting state consists of an equilibrium mixture of a tris(amido)AlIII dimer and a monomeric tris(amido)Al III-carboxamide adduct, and the turnover-limiting step involves intramolecular nucleophilic attack of an amido ligand on the coordinated carboxamide or subsequent rearrangement (intramolecular ligand substitution) of the tetrahedral intermediate. Fundamental mechanistic differences between these tertiary transamidation reactions and previously characterized transamidations involving secondary amides and primary amines suggest that tertiary amide/secondary amine systems are particularly promising for future development of metal-catalyzed amide metathesis reactions that proceed via transamidation.
