1,2-Dibromoethane → HCID 22881085, compound

Participants

Reaction Steps

Magnesium (3.4 g) and a solution of 1,2-dibromoethane (5.3 ml, 60.8 mmol) in diethyl ether (40 ml) were successively added to a solution of 2-bromonaphthalene (12.6 g, 60.8 mmol) in diethyl ether (160 ml) at room temperature in a nitrogen stream and this reaction solution was refluxed under heating for 2.5 hours. The reaction solution was gradually cooled and a solution of (2S,4R)-N-t-butoxycarbonyl-4-(t-butyldimethylsiloxy)prolinal (10 g, 30.4 mmol) in tetrahydrofuran (50 ml) was added dropwise thereto under cooling with ice. Then, the reaction solution was stirred at room temperature for 1 hour. After addition of water, the reaction solution was concentrated in vacuo and was poured into a liquid mixture of ethyl acetate with water. The organic layer was washed with saturated aqueous sodium chloride, dried over anhydrous sodium sulfate, and concentrated in vacuo. The resulting oily residue was subjected to silica gel column chromatography (Wakogel™ C-300, heptane-ethyl acetate=4:1) to give (2S,4R)-N-t-butoxycarbonyl-4-t-butyldimethylsiloxy-2-[hydroxy(2-naphthyl)methyl]pyrrolidine (9.38 g, yield: 67.5%) as a yellow oily substance.

Provenance & Evidence