Methanol → 1-tert-Butyl 2-methyl (2S,4R)-4-{[6-(benzyloxy)pyridin-2-yl]oxy}pyrrolidine-1,2-dicarboxylate

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Reaction Steps

A 500 mL round bottom flask under nitrogen was charged with the product of Step 2 (7.17 g, 17.30 mmol), methanol (50 ml), and dichloromethane (50 ml). Attached an addition funnel containing trimethylsilyldiazomethane in diethyl ether (2.0M) (25.9 ml, 51.9 mmol). Cooled reaction flask in an ice bath. Added contents of addition funnel dropwise. Bubbles. HPLC/MS looks good after 0.5 hours. Quenched by dropwise addition of 2.5% potassium bisulfate. Evaporated to remove methanol. Added water. Extracted three times with ethyl acetate, dried with anhydrous magnesium sulfate, filtered and rotary evaporated filtrate. Subjected to flash column chromatography eluting with 80 hexane/20 ethyl acetate. Evaporation of fractions containing product gave the title compound as a colorless oil. (6.50 g, 15.17 mmol, 88% yield). LCMS (ES+) m/z 429.3 (M+H)+.

Provenance & Evidence