Iridium-Catalyzed Single-Step N-Substituted Lactam Synthesis from Lactones and Amines

Abstract

Catalytic lactam synthesis was achieved directly from lactones and amines using an Ir catalyst. Three sequential transformations—aminolysis of lactone, N-alkylation of amine with hydroxyamide, and intramolecular transamidation of aminoamide—afforded the corresponding N-substituted lactams.

Visible‐Light‐Driven C−H Oxidation of Cyclic Tertiary Amines: Access to Synthetic Strychnos Alkaloids with Antiviral Activity

“…Traditionally, lactams are synthesized by lactamization of lactones with amines or by cyclization of aminoalcohols or of amidoalkenes . However, these and related known cyclization methods require harsh reaction conditions, large amounts of catalyst and ligand, or long reaction times and tedious workup procedures.…”

Insights into Ammonia Borane-Enabled Green Synthesis of N-Substituted Lactams from Biomass-Derived Keto Acids and Amines

“…1−3 Lactam synthesis can employ γ-butyrolactone or butanediol as reactants. 4,5 However, utilization of low-cost keto acid feedstocks that are directly obtainable from lignocellulosic biomass, such as levulinic acid (LA), provides new opportunities for more sustainable and cost-effective processes. 6 Strategies for the synthesis of N-substituted lactams from keto acids and amines have earlier been devised using homogeneous catalysts, such as Ru-or Ir-complexes, AlCl 3 , RuCl 3 , In(OAc) 3 , and ionic liquids.…”

“…N -Substituted lactams are heterocyclic compounds that are widely employed in the synthesis of more complex molecular structures of pesticides, pharmaceuticals, and surfactants. − Lactam synthesis can employ γ-butyrolactone or butanediol as reactants. , However, utilization of low-cost keto acid feedstocks that are directly obtainable from lignocellulosic biomass, such as levulinic acid (LA), provides new opportunities for more sustainable and cost-effective processes …”

A Heterogeneous Niobium(V) Oxide Catalyst for the Direct Amidation of Esters

“…Recently, sodium methoxide,6 La(OTf) 3 ,7 and Lewis acids supported on ionic liquids5d have been reported as more effective catalysts for the amidation of esters with various amines, though these methods are not effective for amidations with less reactive amines such as aniline. Ru8a and Ir complexes8b,c catalyze direct amidation from esters and amines driven by a hydrogen transfer‐type mechanism with liberation of H 2 . These excellent homogeneous catalytic systems suffer from the necessity of solvent and difficulties in catalyst reuse and catalyst–product separation (except for Lewis acid/ionic liquids5d).…”