Methanol, magnesium salt (2:1) → HCID 19705548, compound

Participants

Reaction Steps

A solution of tert-butyl N-tert-butyloxycarbonyl-3-(2-methylpropyl)-2-oxo-α-(propen-2-yl)-3-pyrrolidineacetate (5.40 g, 13.7 mmol) in MeOH (70 mL) is treated with magnesium methoxide (74.7 mL, 68.5 mmol, 10.3 wt % in MeOH). The resultant solution is stirred under N2 at room temperature for 16 hours. The solution is quenched with 1:1 glacial AcOH/H2O (100 mL). The solution is reduced to a minimal volume under reduced pressure, and the unprotected lactam is extracted into CH2Cl2 (3×100 mL). The organic layers are combined, washed with saturated NH4Cl (100 mL), brine (100 mL), dried over anhydrous Na2SO4, filtered, and concentrated under reduced pressure to give 4.75 g of a gold oil. The oil is purified by silica gel chromatography (100 g SG, 25% EtOAc/hexane) to yield 3.85 g (96%) of the title compound as an off-white, low-melting solid.

Provenance & Evidence