(S)-4-Benzyl-2-oxazolidinone → (S)-4-Benzyl-3-[(S)-1-(2,4-dimethoxybenzyl)-5-oxopyrrolidine-3-carbonyl]-2-oxazolidinone

Beteiligte Stoffe

Reaktionsschritte

To a solution of 1-(2,4-dimethoxybenzyl)-5-oxopyrrolidine-3-carboxylic acid (20 g) prepared according to the same procedures as Preparation 5 in chloroform (200 ml) were sequentially added (S)-4-benzyl-2-oxazolidinone (15.2 g) and WSC.HCl (16.4 g), 4-(dimethylamino)pyridine (4.4 g) at room temperature, and the mixture was stirred for 3 hours. This reaction solution was washed with a 5 wt % aqueous solution of sodium hydrogen carbonate and a saturated aqueous solution of sodium chloride, dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (eluent: n-hexane/ethyl acetate=1/1 to 1/3), subjected to azeotropic drying with toluene, and dried under reduced pressure to give the titled compound (17.2 g).

Herkunft & Nachweise