Rhodium carbenoid N-H insertion reactions of primary ureas: solution and solid-phase synthesis of imidazolones.
[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.
Lee
Sang-Hyeup
SH
Department of Chemistry, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, California 92037, USA.
Clapham
Bruce
B
Koch
Guido
G
Zimmermann
Jürg
J
Janda
Kim D
KD
D020650:Combinatorial Chemistry Techniques; D003500:Cyclization; D007093:Imidazoles / Q000138:chemical synthesis*; D012238:Rhodium / Q000737:chemistry; D014508:Urea / Q000737:chemistry
D007093:Imidazoles; C117197:imidazolone; D014508:Urea; D012238:Rhodium