Methanesulfonic Acid → (S)-3-[4-(3-fluorobenzyloxy) benzylamino]pyrrolidin-2-one

Beteiligte Stoffe

Reaktionsschritte

To a 2M solution of (S)-3-aminopyrrolidin-2-one (1.47 g, 14.6 mmol), prepared as described in Example 5, in anhydrous methanol 2.0 g of 3 Å molecular sieves and 0.77 g NaBH3CN (12 mmol) were added; after 10 minutes, 3.4 g (14.8 mmol) of 4-(3-fluorobenzyloxy)benzaldehyde in 40 ml of anhydrous methanol were added. The reaction was carried out for 3 hours, then the mixture filtered, the solution was evaporated yielding a residue which was directly flash-chromatographed on silica gel (eluant: CHCl3:CH3OH:NH3 (30%) 97:3:0.3, v:v:v) to give a white solid (3.4 g; 74%). The free base thus obtained was treated with a stoichiometric amount of methanesulfonic acid to give the title compound m.p. 140.5-143.5° C.

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