title: N,N-diethylurea-catalyzed amidation between electron-deficient aryl azides and phenylacetaldehydes.
abstract: Urea structures, of which N,N-diethylurea (DEU) proved to be the most efficient, were discovered to catalyze amidation reactions between electron-deficient aryl azides and phenylacetaldehydes. Experimental data support 1,3-dipolar cycloaddition between DEU-activated enols and electrophilic phenyl azides, especially perfluoroaryl azides, followed by rearrangement of the triazoline intermediate. The activation of the aldehyde under near-neutral conditions was of special importance in inhibiting dehydration/aromatization of the triazoline intermediate, thus promoting the rearrangement to form aryl amides.
authors.affiliation: Department of Chemistry, KTH - Royal Institute of Technology , Teknikringen 36, Stockholm, Sweden.
authors.forename: Sheng
authors.initials: S
authors.lastname: Xie
authors.forename: Olof
authors.initials: O
authors.lastname: Ramström
authors.forename: Mingdi
authors.initials: M
authors.lastname: Yan
mesh_terms: D000079:Acetaldehyde / Q000031:analogs & derivatives* / Q000737:chemistry; D000577:Amides / Q000138:chemical synthesis / Q000737:chemistry*; D001386:Azides / Q000737:chemistry*; D002384:Catalysis; D004121:Dimethyl Sulfoxide / Q000737:chemistry; D004583:Electrons; D008956:Models, Chemical; D015394:Molecular Structure; D014230:Triazoles / Q000737:chemistry; D014508:Urea / Q000031:analogs & derivatives* / Q000737:chemistry
chemical_list: D000577:Amides; D001386:Azides; D014230:Triazoles; C022223:diethylurea; D014508:Urea; D000079:Acetaldehyde; C013192:phenylacetaldehyde; D004121:Dimethyl Sulfoxide