N-bromobutanimide → Ethyl 4-bromo-5-methyl-1H-pyrrole-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

Ethyl 5-methyl-1H-pyrrole-2-carboxylate (Intermediate 20, 12.3 g, 0.803 mmol) was dissolved in anhydrous DCM and cooled to −5° C. N-bromosuccinimide (14.23 g; 0.0803 mmol) was added and the reaction stirred for 10 min and then poured into ice-cold 2 N sodium hydroxide (500 ml). The brown solution was extracted with EtOAc (2×150 ml), the combined organic extracts were washed with water, brine and dried over Na2SO4, then concentrated in vacuo to give a brown solid which was dried under vacuum. (16.5 g).

Provenance & Evidence