tert-Butanol → N-(tert-Butoxycarbonyl)-[1-(2,4-dichlorophenyl)-5-(4-chlorophenyl)-1H-pyrazol-3-yl]amine

Participants

Reaction Steps

3.25 g of the 1-(2,4-dichlorophenyl)-5-(4-chlorophenyl)pyrazole-3-carboxylic acid obtained according to Example 1C) and then 1.32 ml of triethylamine are added to a solution of 2.05 ml of diphenylphosphoryl azide in 40 ml of anhydrous t-butanol and the reaction mixture is refluxed under nitrogen for 12 hours. After cooling, it is treated with a saturated solution of NaHCO3 and extracted with ethyl acetate. After washing with water and then with a saturated solution of NaCl, drying over MgSO4 and evaporation of the solvents, the crude product is purified by chromatography on 70-230 mesh silica gel using CH3OH/CH2Cl2 1/99 (v/v) as the eluent to give 1.09 g of the expected product.

Provenance & Evidence