L-Methionine → Benzyl 4-cyano-4-methylpiperidine-1-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

LiHMDS (47.6 mL, 47.6 mmol) was added dropwise via syringe to the mixture of benzyl 4-cyanopiperidine-1-carboxylate (8.00 g, 31.8 mmol, [Oakwood]) in THF (50 mL) at about −78° C. and stirred for about 1 h. Met (6.76 g, 47.6 mmol) was added dropwise via syringe at about −78° C. and the mixture was stirred overnight at rt. The solution was cooled to 0° C. and saturated aqueous NH4Cl (200 mL) was added. The mixture was extracted with DCM (3×300 mL). The combined organic extracts were dried over anhydrous Na2SO4, filtered and concentrated in vacuo. The sample was deposited onto silica gel and purified by column chromatography eluting with 10:1 pet ether/EtOAc to give benzyl 4-cyano-4-methylpiperidine-1-carboxylate (6.6 g, 74%): LC/MS (Table 2, Method i) Rt=2.03 min; MS m/z: 259 (M+H)+.

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