1: Org Lett. 2003 Oct 2;5(20):3599-602.  

Versatile access to benzhydryl-phenylureas through an unexpected rearrangement
during microwave-enhanced synthesis of hydantoins.

Muccioli GG, Wouters J, Poupaert JH, Norberg B, Poppitz W, Scriba GK, Lambert
DM.

Unite de Chimie Pharmaceutique et de Radiopharmacie, Ecole de Pharmacie, Faculte
de Medecine, Universite catholique de Louvain, Avenue E. Mounier 73, UCL-CMFA
7340, B-1200 Bruxelles, Belgium.

[reaction: see text] A new access to benzhydryl-phenylureas is described. These
new interesting urea derivatives were obtained by reaction of substituted
benzils with substituted phenylureas under microwave irradiation.
Phenylthiourea, when reacted with benzil, gave 3-phenyl-thiohydantoin. Moreover,
benzylurea, as phenethylurea, gave the corresponding 3-substituted hydantoin
derivatives, demonstrating that only phenylurea derivatives can result in
benzhydryl-phenylureas under the applied conditions. This new reaction proved to
be an easy access to substituted 1-benzhydryl-3-phenyl-ureas.

PMID: 14507182 [PubMed - in process]