Carbon tetrabromide → 3-Bromo-pyrrolidine-1-carboxylic acid tert-butyl ester

Beteiligte Stoffe

Reaktionsschritte

Triphenylphosphine (727 mg, 2.77 mmol) was added to a stirred solution of tert-butyl 3-hydroxypyrrolidine-1-carboxylate (173 mg, 0.924 mmol) and carbon tetrabromide (919 mg, 2.77 mmol) in THF (3.00 mL) at 0° C., and the resulting mixture was allowed to warm slowly to rt. After 20 h, the reaction was filtered and concentrated in vacuo. Purification of the crude residue by flash chromatography on silica gel (gradient elution; 10%-40% EtOAc/hexanes as eluent) afforded the title compound i-5a m/z (ES) 250 (MH)+. 1H NMR (500 MHz, CDCl3): δ 4.49 (m, 1H), 3.81 (m, 2H), 3.63 (m, 1H), 3.53 (m, 1H), 2.33 (m, 1H), 2.26 (m, 1H), 1.49 (s, 9H).

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