2-bromo-1-(6-methyl-pyridin-2-yl)-ethanone hydrobromide synthesis

Yield:147097-80-1 95%

Reaction Conditions:

with hydrogen bromide;bromine;acetic acid in dichloromethane at 20; for 3 h;Cooling with ice;

Steps:

Intermediate 15A: 2-bromo- 1 -(6-methylpyridin-2-yl)ethanone, hydrobromide

To an ice-cold solution of 1-(6-methylpyridin-2-yl)ethanone (8.7 g, 64.4 mmol) and hydrobromic acid (23.31 mL, 129 mmol, 33 % solution in AcOH) in DCM (100 mL) was added bromine (3.32 mL, 64.4 mmol) and the reaction mixture was stirred at RT for 3 h. Soon a solid precipitated out that was filtered off and the filter-cake was washed several times with DCM. The yellow solid was air-dried to obtain intermediate 15A (18.0g, 95 % yield) as a bright yellow solid. ‘H NMR (400 MI-Tz, DMSO-d6) d ppm 8.01 - 7.93 (m, 1H), 7.88 (s, 1H), 7.62 (d, J= 7.8 Hz, 1H), 5.03 (s, 2H), 2.59 (s, 3H).

References:

WO2018/132279,2018,A1 Location in patent:Page/Page column 52; 53