Carbon tetrabromide → (S)-t-butyl 2-(2,2-dibromovinyl)pyrrolidine-1-carboxylate

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Reaktionsschritte

A solution of triphenylphosphine (21.1 g, 80.3 mmol) and carbon tetrabromide (13.32 g, 40.16 mmol) in dichloromethane (300 mL) at 0° C. was treated with a solution of 2-formylpyrrolidine-1-carboxylic acid tert-butyl ester (4.0 g, 20.08 mmol) in dichloromethane (10 mL) dropwise via syringe. The solution was stirred for 1 hour at room temperature, poured into a saturated sodium bicarbonate solution and separated. The organic phase was dried (MgSO4), filtered and concentrated. The concentrate was purified by flash chromatography on silica gel using 0-1% methanol/dichloromethane to give 6.13 g (86% yield) of the desired product. 1H NMR (300 MHz, CHLOROFORM-D) δ ppm 1.47 (s, 9H), 1.81 (m, 3H), 2.16 (m, 1H), 3.39 (m, 2H), 4.37 (s, 1H), 6.38 (s, 1H).

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