Urea → Methyl 2-chloro-5-hydroxybenzoate

Participants

Reaction Conditions

Reaction Steps

Compound of example 156 (9 g, 48.5 mmol) was subjected to diazotization using NaNO2 (4.5 g 48.5 mmol) in water (50 mL) and H2SO4 (10%, 100 mL). Excess nitrous acid was neutralized with urea. The reaction mixture was poured into a suspension of CuSO4.5H2O (144 g, 577 mmol) and Cu2O (5.22 g, 41.4 mmol) in water (900 mL) at 0° C. The reaction mixture was stirred for 15 min. at 0-5° C. and was then extracted using diethyl ether (3×200 mL). The organic extract was washed, dried (anhydrous Na2SO4), concentrated and purified using a silica gel column and 10% EtOAc in petroleum ether (60-80° C.) as eluant to obtain the title compound.

Provenance & Evidence