2,5-Dibromopyridine → 1-(5-Bromo-2-pyridinyl)-4-(phenylsulfonyl)piperazine

Participants

Reaction Conditions

Reaction Steps

A 350 ml, pressure vessel was charged with 4-(phenylsulfonyl)piperazine hydrochloride (1.50 g, 5.71 mmol, Example 15, step 1), 2,5-dibromopyridine (1.76 g, 7.42 mmol, Sigma-Aldrich, St. Louis, Mo.), 100 mL of toluene, sodium tert-butoxide (1.37 g, 14.3 mmol), tris(dibenzylideneacetone)dipalladium (0) (0.105 g, 0.114 mmol, Strem Chemical Inc, Newburyport, Mass.), and 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (XantPhos) (0.198 g, 0.343 mmol, Strem Chemical Inc, Newburyport, Mass.). The tube was sealed and heated at 110° C. for 3 h. After that time, the reaction was cooled to room temperature, diluted with water (20 mL) and extracted with EtOAc (2×50 mL). The organic layer was separated, dried (MgSO4) and concentrated to give a yellow solid. This solid was slurried with cold (0° C.) MeOH (25 mL) to give 1-(5-bromo-2-pyridinyl)-4-(phenylsulfonyl)piperazine (0.957 g) as a light yellow solid.

Provenance & Evidence