Dimethyl Disulfide → 2-Bromo-5-(methylthio)pyridine

Participants

Reaction Conditions

Reaction Steps

A stirring suspension of 2,5-dibromopyridine (10 g, 0.042 mol) in anhydrous diethyl ether (240 mL) was cooled to −78° C. under nitrogen before the dropwise addition of n-butyl lithium (1.6M in hexanes, 0.044 mol, 27.5 mL). The reaction was stirred at −78° C. for 4 hours before the dropwise addition of methyl disulphide (0.044 mol, 3.91 mL). The reaction was allowed to warm to 22° C. and stirred for a further 18 hours. The reaction was quenched with water (100 mL) and the aqueous and organic layers partitioned. The aqueous layer was extracted with diethyl ether (×3). The extracts were combined with the organic layer, washed with brine, dried (MgSO4) and the solvent removed. The crude product was purified by crystallisation from diethyl ether at −20° C. to afford the title compound as a white solid: 1H NMR (CDCl3)-δ 2.50 (s, 3H), 7.38 (dd, 1H), 7.42 (dd, 1H), 8.23 (d, 1H).

Provenance & Evidence