Propanedioic acid, 2-amino-, 1,3-diethyl ester, hydrochloride (1:1) → methyl 3-amino-5-(tert-butyl)-1H-pyrrole-2-carboxylate

Participants

Reaction Steps

To a stirred sodium methoxide solution (15% by weight, 80 mL total) was added drop-wise a solution of 1-cyano-3,3-dimethylbut-1-en-2-yl 4-methylbenzenesulfonate (10.0 g, 36 mmol) and diethyl aminomalonate hydrochloride salt (9.0 g, 43 mmol) in methanol (50 mL). After the addition was completed, the reaction was stirred at room temperature for 2 hours, the solvent was removed under vacuum and the crude product was dissolved in water and extracted with ethyl acetate. The combined organic layers was washed with brine, dried and the solvent removed under vacuum. The crude product was purified by column chromatography (silicagel, dichloromethane:methanol 95:5) to afford 2.4 g of the desired methyl 3-amino-5-tert-butyl-1H-pyrrole-2-carboxylate used as such in the next step.

Provenance & Evidence