1,2-Dichloro-3-isocyanatobenzene → N-(4-tert-butylpyridyl)-N'-(2,3-dichlorophenyl)urea

Participants

Reaction Steps

A solution of 2-amino-4-tert-butylpyridine (192 mg) and 2,3-dichlorophenyl isocyanate (240 mg) in anh. toluene (15 mL) was heated at 70° C. under argon for 24 h. The resulting mixture was diluted with EtOAc (200 mL) then washed with water (125 mL). The organic layer was dried (MgSO4) and concentrated under reduced pressure to give a gum. Trituration of the gum with hexanes afforded N-(4-tert-butylpyridyl)-N′-(2,3-dichlorophenyl) urea as a white solid (394 mg, 91%): TLC (2:1 hexanes/ethyl acetate) Rf 0.40; FAB-MS m/z 338 ((M+H)+). B2a. Reaction of a Heterocyclic Amine with N,N′-Carbonyldiimidazole Followed By Reaction with a Substituted Aniline

Provenance & Evidence