N-Heterocyclic Olefins as Robust Organocatalyst for the Chemical Conversion of Carbon Dioxide to Value-Added Chemicals

• Published in: ChemSusChem Vol. 9; no. 15; pp. 1980 - 1985
• Main Authors: Saptal, Vitthal B., Bhanage, Bhalchandra M.
• Format: Journal Article
• Language: English
• Published: Germany Blackwell Publishing Ltd 09.08.2016; Wiley Subscription Services, Inc
• Subjects: Alkenes - chemistry; Amines; Amines - chemistry; Aziridines - chemistry; Carbon; Carbon dioxide; Carbon Dioxide - chemistry; carbon dioxide fixation; Catalysis; Chemical reactions; Conversion; cycloaddition; Cycloaddition Reaction; Nitrogen - chemistry; nitrogen heterocycles; Olefins; organocatalysis; Oxazolidinones - chemistry; Reducing agents; Siloxanes - chemistry; Transformations; zwitterions; organocatalysis; zwitterions; cycloaddition; nitrogen heterocycles; carbon dioxide fixation
• ISSN: 1864-5631; 1864-564X
• DOI: 10.1002/cssc.201600467

In this report, the activity of N‐heterocyclic olefins (NHOs) as a newly emerging class of organocatalyst is investigated for the chemical fixation of carbon dioxide through reactions with aziridines to form oxazolidinones and the N‐formylation of amines with polymethylhydrosiloxane (PMHS) or 9‐borabicyclo[3.3.1]nonane (9‐BBN) as the reducing agent under mild conditions. The exocyclic carbon atoms of NHOs are highly nucleophilic owing to the electron‐donating ability of the two nitrogen atoms. This high nucleophilicity of the NHOs activates CO2 molecules to form zwitterionic NHO–carboxylate (NHO–CO2) adducts, which are active in formylation reactions as well as the carboxylation of aziridines to oxazolidinones. NHO limits: N‐Heterocyclic olefins (NHOs) activate CO2 for the formation of oxazolidinones from aziridines as well as the N‐formylation of amines with polymethylhydrosiloxane (PMHS) or 9‐borabicyclo[3.3.1]nonane (9‐BBN) as the reducing agent. These transformations proceed under solvent‐free and metal‐free mild conditions.