N-bromobutanimide → Tert-butyl 4-(5-bromo-1,3-thiazol-2-yl)piperidine-1-carboxylate

Beteiligte Stoffe

Reaktionsschritte

To a solution of tert-butyl 4-(thiazol-2-yl)piperidine-1-carboxylate (530 mg, 1.97 mmol) in acetonitrile (10 mL) was added NBS (1.40 g, 7.86 mmol). The mixture was stirred at RT for 14 hours and heated at 50° C. for 4 hours. The reaction mixture with some starting material recovered was poured into a solution of Na2SO3 (30 mL) and 6N NaOH (2 mL). The aqueous layer was extracted with EtOAc, dried over MgSO4, and the combined organics concentrated in vacuo. The residue was purified by silica gel chromatography to provide tert-butyl 4-(5-bromothiazol-2-yl)piperidine-1-carboxylate as a yellow oil [210 mg (0.61 mmol); 1H NMR (300 MHz, CDCl3) 7.59 (s, 1H), 4.20 (brd, J=12.9 Hz, 2H), 3.13 (tt, J=3.8, 11.5 Hz, 1H), 2.89 (t, J=11.6 Hz, 2H), 2.08 (d, J=11.7 Hz, 2H), 1.72 (dq, J=4.3, 11.9 Hz, 2H), 1.49 (s, 9H)].

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