Triethylamine → trans-2-(Methylpropylcarbamoyl)-cyclopropane carboxylic acid ethyl ester

Beteiligte Stoffe

Reaktionsschritte

Add 1-hydroxybenzotriazole (HOBT) (1.46 g, 10.8118 mmol), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDCI) (2.07 g, 10.8118 mmol) to a solution of crude trans-cyclopropane-1,2-dicarboxylic acid monoethyl ester (1.71 g, 10.8118 mmol) in N,N-dimethylformamide (11 mL). Stir for 30 minutes. Add triethylamine (2.26 mL, 16.2177 mmol) and methylpropylamine (1.11 mL, 10.8118 mmol) and stir for 16 hours. Quench with 10% aqueous potassium carbonate (10 mL) and extract with ethyl acetate (3×50 mL). Combine the organic extracts, wash with 0.1 N aqueous citric acid (30 mL) and 1 N lithium chloride, dry (magnesium sulfate), concentrate and crystallize with xylenes to give the desired compound (1.02 g, 50%).

Herkunft & Nachweise