Diisopropylethylamine → 3-Bicyclo[2.2.1]hept-2-yl-2-[4-(2,6-difluoro-phenoxy)-2-oxo-2,5-dihydro-pyrrol-1-yl]-propionic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

In a round bottom flask was placed 2-amino-3-bicyclo[2.2.1]hept-2-yl-propionic acid methyl ester (206 mg, 1.04 mmol), N,N-diisopropylethylamine (390 μL, 2.24 mmol) and 4-bromo-3-(2,6-difluoro-phenoxy)-but-2-enoic acid ethyl ester (prepared as in Example 36, 390 mg, 2.24 mmol) in acetonitrile (10 mL). This mixture was then split into two 5 mL portions and placed in two sealed microwave reaction tubes and heated in a microwave reactor at 140° C. for 1 h. The contents of the two reaction tubes were combined, concentrated in vacuo and diluted with dichloromethane (20 mL) and washed with a 1N aqueous hydrochloric acid solution (10 mL), a saturated sodium bicarbonate solution (10 mL), dried over magnesium sulfate, filtered and concentrated in vacuo. Purification by AnaLogix IntelliFlash flash chromatography (12 g column, 15% ethyl acetate/hexanes to 30% ethyl acetate/hexanes) afforded 3-bicyclo[2.2.1]hept-2-yl-2-[4-(2,6-difluoro-phenoxy)-2-oxo-2,5-dihydro-pyrrol-1-yl]-propionic acid methyl ester (87 mg, 15%) as a yellow oil.

Provenance & Evidence