N-Alkylation by Hydrogen Autotransfer Reactions [corrected]
Xiantao Ma1,2, Chenliang Su2, Qing Xu3
1College of Chemistry and Materials Engineering, Wenzhou University, Wenzhou, Zhejiang, 325035, China.
Topics in Current Chemistry (Cham)
|August 31, 2016
Summary
Dehydrative N-alkylation reactions efficiently convert amines and amides to valuable derivatives using alcohols. Recent advancements focus on green chemistry, novel catalysts, and mechanistic understanding for sustainable synthesis.
Area of Science:
- Organic Chemistry
- Green Chemistry
- Catalysis
Background:
- Amine/amide derivatives are crucial across all chemical fields.
- Alcohols offer a green and atom-economical approach for N-alkylation.
- Dehydrative N-alkylation via hydrogen autotransfer is a rapidly developing area.
Purpose of the Study:
- To review recent progress in dehydrative N-alkylation of amines/amides with alcohols.
- To highlight technical and conceptual advances in the last decade.
- To discuss mechanistic insights, novel activation protocols, and future research directions.
Main Methods:
- Review of homogeneous and heterogeneous transition metal-catalyzed reactions.
- Exploration of transition metal-free, catalyst-free, and autocatalyzed methods.
- Analysis of computational mechanistic studies and novel alcohol activation protocols (e.g., air-promoted).
Main Results:
- Significant development in diverse catalytic systems (transition metal, nano-materials, biomimetic).
- Emergence of electrochemical and aerobic oxidative N-alkylation methods.
- Increased understanding of hydrogen transfer and alcohol activation mechanisms.
Conclusions:
- Dehydrative N-alkylation offers a sustainable route for synthesizing amine/amide derivatives.
- Recent innovations have expanded the scope and efficiency of these reactions.
- Further research is needed to address remaining challenges and explore new frontiers.
Keywords:
Aerobic oxidative dehydrogenationAlcohol activationAlcohol oxidationAlcoholsAmidesAmine oxidationAminesAnaerobic dehydrogenationAsymmetric N-alkylationAutocatalysisBorrowing hydrogenCatalyst-freeDehydrationHeterogeneous catalysisHomogeneous catalysisHydrogen autotransferN-AlkylationReductive N-alkylationRelay raceTransfer hydrogenationTransition metal catalystsTransition metal-free
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