title: Rhodium carbenoid N-H insertion reactions of primary ureas: solution and solid-phase synthesis of imidazolones.
abstract: [reaction: see text] The solution and solid-phase synthesis of imidazolones is reported. The key step for the preparation of these compounds is the N-H insertion reaction of primary ureas into highly reactive rhodium carbenoid intermediates. Typically, a soluble or support-bound alpha-diazo-beta-ketoester is treated with a rhodium carboxylate catalyst in the presence of a primary urea to give the corresponding N-H insertion product. Subsequent acid-catalyzed cyclodehydration of these insertion products affords the desired imidazolone products.
authors.affiliation: Department of Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, California 92037, USA.
authors.forename: Sang-Hyeup
authors.initials: SH
authors.lastname: Lee
authors.forename: Bruce
authors.initials: B
authors.lastname: Clapham
authors.forename: Guido
authors.initials: G
authors.lastname: Koch
authors.forename: Jürg
authors.initials: J
authors.lastname: Zimmermann
authors.forename: Kim D
authors.initials: KD
authors.lastname: Janda
mesh_terms: D020650:Combinatorial Chemistry Techniques; D003500:Cyclization; D007093:Imidazoles / Q000138:chemical synthesis*; D012238:Rhodium / Q000737:chemistry; D014508:Urea / Q000737:chemistry
chemical_list: D007093:Imidazoles; C117197:imidazolone; D014508:Urea; D012238:Rhodium