ethyl 4-amino-3-bromo-5-nitrobenzoate synthesis

Yield:82760-42-7 100%

Reaction Conditions:

with bromine in dichloromethane at 40; for 4 h;

Steps:

B.8.2 Ethyl 4-amino-3-bromo-5-nitrocybenzoate

To a solution of ethyl 4-amino-3-nitrobenzoate [76918-64-4] (55.0 g, 261 mmol) in DCM (2 L) was added bromine (62.7 g, 392 mmol) dropwise. The reaction mixture was stirred at 40°C for 4 h. The reaction mixture was poured out into a saturated aqueous solution of Na2SO3 (2 L) under stirring. The layers were separated and the aqueous phase was extracted with DCM (2 x 1 L). The combined organic extracts were washed with an aqueous solution of NaHCO₃ (1 L), dried over Na2SO4, filtered and concentrated in vacuo. The residue was dissolved in DCM (1.5 L). The suspension was filtered through a pad of Celite. The filtrate was concentrated in vacuo to afford intermediate K2 (76 g, quant.) as a yellow solid.

References:

WO2020/234333,2020,A1 Location in patent:Page/Page column 16; 63-64