tert-Butyl piperazine-1-carboxylate → Tert-butyl 4-(6-bromopyridin-3-yl)piperazine-1-carboxylate

Participants

Reaction Steps

Into the mixture solution of 2-bromo-5-iodopyridine (9.15 g, 32.2 mmol), tert-butyl piperazine-1-carboxylate (5 g, 27 mmol) in Toluene (90 mL) was added Tris(dibenzylideneacetone)dipalladium (0) (0.983 g, 1.1 mmol), 4,5-Bis(diphenylphosphino)-9,9-dimethylxanthene (0.17 g, 3.2 mmol) and NaOtBu (7.8 g, 80.5 mmol). Then the reaction mixture was flushed with Argon and stirred for 2 h. The reaction mixture was extracted with ethyl acetate and washed with brine. After drying with MgSO4, the organic solvent was removed under vaco., the residue was purified by crystallization from mixture of DCM and Hexane to get 8.4 g of tert-butyl 4-(6-bromopyridin-3-yl)piperazine-1-carboxylate 7.13. 1H NMR (400 MHz, CDCl3) ppm: δ 8.01 (d, J=3.2 H2, 1H), 7.32 (d, J=8.4 Hz, 1H), 7.07 (d, d, J=3.2, 8.4 Hz, 1H), 3.59 (t, J=5.4 Hz, 4H), 3.237 (t, J=5.4 Hz, 4H), 1.478 (s, 9H).

Provenance & Evidence