2-Bromopyridine → 2-(2'-Thienyl)pyridine

Participants

Reaction Steps

To a solution of thiophene (4.7 mL, 59.4 mmole) at 0° C. was added 2.5M n-butyllithium (24 mL, 59.4 mmole) dropwise via syringe. The solution was stirred 3 h and was transferred via cannula into a stirred solution of zinc chloride (8.6 g, 63.4 mmole) in 60 mL THF at room temperature. This solution was stirred for 1 h and was transferred via cannula into a stirred solution of 2-bromopyridine (3.8 mL, 39.6 mmole) and tetrakis-triphenylphosphine palladium (0.22 g, 0.2 mmole) in 100 mL of THF. The solution was stirred overnight at room temperature and was then quenched with saturate ammonium chloride solution (100 mL) and extracted with ether (3×100 mL). The ether extracts were washed with brine (1×100 mL), dried over MgSO4, filtered and concentrated to yield 8.4 g of crude residue. The material was chromatographed (silica gel, 10% ether/hexanes) to yield 5.0 g (78%) of a pale yellow solid.

Provenance & Evidence