title: N-formylation and N-methylation of amines using metal-free N-heterocyclic carbene catalysts and CO2as carbon source.
abstract: N-formylation and N-methylation of amines are important reactions that are used to produce a wide range of key intermediates and compounds. This protocol describes the environmentally benign N-formylation and N-methylation of primary and secondary amines using carbon dioxide (CO2) as the carbon source, hydrosilanes as reductants and N-heterocyclic carbenes (NHCs) as catalysts. Using CO2as a reagent has the advantage of low cost and negligible toxicity. However, the catalyst is air-sensitive and must be generated fresh before use; consequently, the techniques used to prepare and manipulate the catalyst are described. The synthetic approach described in this protocol does not use any toxic reagents; using the appropriate catalyst, N-formylated or N-methylated products can be obtained with high selectivity. The overall time for catalyst preparation and for conducting several catalytic reactions in parallel is 15-48 h, depending on the nature of the substrates.
authors.affiliation: Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
authors.forename: Felix D
authors.initials: FD
authors.lastname: Bobbink
authors.affiliation: Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
authors.forename: Shoubhik
authors.initials: S
authors.lastname: Das
authors.affiliation: Institut des Sciences et Ingénierie Chimiques, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Dyson
mesh_terms: D000588:Amines / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry*; D002384:Catalysis; D006571:Heterocyclic Compounds / Q000737:chemistry*; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D008745:Methylation; D009584:Nitrogen / Q000737:chemistry*
chemical_list: D000588:Amines; D006571:Heterocyclic Compounds; D002245:Carbon Dioxide; C030011:carbene; D002244:Carbon; D009584:Nitrogen; D008697:Methane