Ethyl Acetate → 1-(5-tert-Butyl-2-methyl-2H-pyrazol-3-yl)-3-(4-hydroxymethyl-phenyl)urea

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a dry flask is added 872 mg (2.5 mmol) of 4-[3-(5-tert-butyl-2-methyl-2H-pyrazol-3-yl)-ureido]-benzoic acid ethyl ester in 30 mL dry methylene chloride and cooled to 0° C. Next, 10.12 mL of 1M DIBAL in hexanes (4 eq., 10.12 mmol) is added and the reaction is allowed to reach room temperature. The mixture is then stirred for 1 hour, and 60 mL of ethyl acetate and 100 mL of sodium tartrate saturated aqueous solution are added, and the mixture is stirred for another 30 min. Then the organic layer is separated and washed with water and dried over magnesium sulfate, filtered, and evaporated to a white solid weighing 720 mg (2.4 mmoles, 95%, ES+(m/z) 303 [M+H]).

Herkunft & Nachweise