Tetrahydrofuran → Ethyl (4S)-2-ethyl-8-(methoxy)-6-[1-(methoxycarbonyl)vinyl]-4-methyl-1-oxo-1,2,3,4-tetrahydro-pyrrolo[1,2-a]-pyrazine-7-carboxylate

Participants

Reaction Steps

To a cold (0° C.) solution of ethyl (4S)-2-ethyl-8-(methoxy)-6-[methoxy(oxo)-acetyl]-4-methyl-1-oxo-1,2,3,4-tetrahydro-pyrrolo[1,2-a]-pyrazine-7-carboxylate (1.0 g, 2.73 mmol) in anhydrous THF (100 mL), a solution of Tebbe reagent (6.0 mL, 0.5 M) in toluene was added. The reaction mixture was stirred at room temperature for one hour. The product mixture was diluted with ether (100 mL) and treated with aq sodium hydroxide (4 mL, 1M). The mixture was filtered. The organic extract was separated, dried over anhydrous sodium sulfate, filtered, and concentrated under vacuum. The residue was subjected to column chromatography on silica gel eluted with ethyl acetate-hexane gradient. Collection and concentration of appropriate fractions provided the olefination product.

Provenance & Evidence