Diisopropylamine → 3-Butyl-ureido-2-chloro-benzoic acid

Participants

Reaction Steps

To N,N-diisopropylamine (1.72 mL, 0.0122 mol) in tetrahydrofuran (12 mL, 0.14 mol), was added 1.6 M n-butyllithium in hexane (7.6 mL) at −78° C. under an atmosphere of nitrogen. After 30 minutes, 3-amino-2-chlorobenzoic acid (586, 1.00 g, 0.00583 mol) was added. After another 30 minutes, 1-isocyanatobutane (2.60 mL, 0.0233 mol) was added at −78° C. under an atmosphere of nitrogen and allowed to stir for two hours. The reaction mixture was warmed up to room temperature and stirred at room temperature for 30 minutes. The reaction was quenched with 1M HCl (aqueous) solution and extracted with ethyl acetate twice. The combined organic layers were washed with brine, dried over anhydrous magnesium sulfate and filtered. The filtrate was concentrated and purified by silica gel column chromatography eluting with dichloromethane:methanol:acetic acid 40:2:1 to give the compound as an off-white solid (587, 147 mg, 9%).

Provenance & Evidence