Carbon tetrabromide → tert-Butyl 4-bromopiperidine-1-carboxylate

Participants

Reaction Steps

To N-Boc-4-hydroxy piperidine (20 g, 100 mmol) in THF (200 ml) at 0° C. was added triphenylphosphine (28.85 g, 110 mmol) followed by carbon tetrabromide (36.48 g, 110 mmol). The solution was stirred at room temperature for 2 h then filtered and concentrated under vacuum. Flash column chromatography using dichloromethane in hexane (10-70%) yielded the product as a colourless oil (23.6 g); δH (CDCl3) 1.47 (9H, s, t-Bu), 1.93 and 2.04 (4H, m, 3,5-piperidinyl CH2), 3.31 and 3.66 (4H, m, 2,6-piperidinyl CH2), and 4.39 (1H, m, 4-piperidinyl H).

Provenance & Evidence