title: Swift and efficient synthesis of 4-phenylquinazolines: involvement of N-heterocyclic carbene in the key cyclization step.
abstract: An original route to 2-alkyamino-4-phenylquinazolines in three steps from simple (hetero)aromatic amines is reported here. The key step involves the intramolecular cyclization of benzoyl arylguanidines performed in [OMIm]Cl ionic liquid. The basic (hetero)aromatic guanidines deprotonate the imidazolium-based ionic liquid, thus triggering the cascade process ultimately leading to the intramolecular cyclization. This reaction is the first example of a Friedel-Crafts-type reaction in which an N-heterocyclic carbene is involved in the formation of the electrophilic intermediate.
authors.affiliation: Département Chimie Moléculaire, UMR 5250 & FR 2607, CNRS/Université de Grenoble, BP 53, 38041 Grenoble Cedex 9, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Debray
authors.forename: Jean-Marc
authors.initials: JM
authors.lastname: Lévêque
authors.forename: Christian
authors.initials: C
authors.lastname: Philouze
authors.forename: Micheline
authors.initials: M
authors.lastname: Draye
authors.forename: Martine
authors.initials: M
authors.lastname: Demeunynck
mesh_terms: D003500:Cyclization; D019791:Guanidine / Q000138:chemical synthesis / Q000737:chemistry; D006571:Heterocyclic Compounds / Q000737:chemistry*; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D015394:Molecular Structure; D011799:Quinazolines / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D006571:Heterocyclic Compounds; D011799:Quinazolines; C030011:carbene; D019791:Guanidine; D008697:Methane