Hydrochloric Acid → 2-Chloro-1-(4-methyl-3-pyridinyl)ethanone hydrochloride

Participants

Reaction Steps

In a 500 mL round bottom flask was placed 1-(4-methyl-3-pyridinyl)ethanone (10.0 g, 74.1 mmol) in 90 mL of Et2O. To this solution was added 88.9 mL of 1 M HCl/Et2O (1.2 eq, 88.9 mmol) with stirring and the solution allowed to stir for 1 h at room temperature, at which point, the precipitate was filtered and washed with Et2O. The solid was then dried in vacuo at about 60° C. This HCl salt (12. g, 70.0 mmol) was then dissolved in 70.0 mL of 1M HCl/acetic acid where 9.34 g (1 eq, 70.0 mmol) of N-chlorosuccinimide (NCS) was added and the reaction allowed to stir under Argon at room temperature overnight. At this point, 300 mL of Et2O was added resulting in an off-white precipitate. This was allowed to stir for 1 h at which point the solid was filtered and rinsed with Et2O to provide 12.0 g (83%) of the desired 2-chloro-1-(4-methyl-3-pyridinyl)ethanone hydrochloride. GC/MS RT=6.60 min; 1H-NMR (DMSO-d6) δ 2.51 (s, 3H), 5.15 (s, 2H), 7.68 (d, 1H), 8.68 (d, 1H), 9.06 (s, 1H); [M]+169 (95%).

Provenance & Evidence