tert-butyl 2-cyanopentanoate

反应条件: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: DBU was added slowly to a solution of cyano-acetic acid tert-butyl ester (6.03 g) in DMF (100 mL) at rt, followed by addition of 1-iodopropane (9.58 mL); the reaction mixture was stirred in an oil bath (bath temperature=80° C.) overnight subsequently. The reaction was cooled, diluted with EtOAc, then washed with cold water, dil. NaCl solution; EtOAc phase was dried over anhydrous sodium sulfate, filtered, concentrated, the residue was column purified to give 2-cyano-2-propyl-pentanoic acid tert-butyl ester (6.87 g) and 2-cyano-pentanoic acid tert-butyl ester (420 mg). 2-Cyano-2-propyl-pentanoic acid tert-butyl ester (1H NMR in CDCl3, δ in ppm) 1.502 (s, 9H), 1.9-1.2 (m, 8H), 0.96 (t, 6H, J=7.0 Hz). 2-Cyano-pentanoic acid tert-butyl ester (1H NMR in CDCl3, δ in ppm) 3.39 (t, 1H, J=7.0 Hz), 1.95-1.83 (m, 2H), 1.6-1.55 (m, 2H), 1.51 (s, 9H), 0.98 (t, 3H, J=7.2 Hz). The reaction was cooled washed with cold water, dil. NaCl solution EtOAc phase was dried over anhydrous sodium sulfate filtered concentrated purified