The highly efficient transamidation of several primary, secondary, and tertiary amides with aliphatic and aromatic amines (primary and secondary) is described. The reaction is performed in the presence of a 5 mol % concentration of different hydrated salts of Fe(III), and the results show that the presence of water is crucial. The methodology was also applied to urea and phthalimide to demonstrate
A novel chitosan-catalyzed transamidation of carboxamides with amines under solvent-free conditions is described. A series of amide derivatives as well as more challenging aryl and alkyl amines with long-chain alkyl substituents could be selectively converted into the corresponding transamidation products, which are frequently found in biologically active compounds and pharmaceuticals. Under similar reaction conditions benzo[d]heterocycles were also obtained via a one-pot synthesis through transamidation and subsequent dehydration. Recyclability of chitosan was demonstrated, with quantitative yields of products obtained without any loss of catalytic activity.
Graphene Oxide: A Metal‐Free Carbocatalyst for the Synthesis of Diverse Amides under Solvent‐Free Conditions
作者:Khushbu P. Patel、Eknath M. Gayakwad、Vilas V. Patil、Ganapati S. Shankarling
DOI:10.1002/adsc.201801673
日期:2019.4.23
solvent‐free reaction conditions providing desired products in good to excellent yields. The one‐pot synthesis of 2,3‐Dihydro‐5H‐benzo[b]‐1,4‐thiazepin‐4‐one moiety by GO catalyzed Aza Michael addition followed by intramolecular transamidation is also described. A plausible reaction mechanistic pathway involving H‐bonding is discussed. The graphene oxide can be recycled and reused up to five cycles without