Ammonium Chloride → HCID 67428980, compound

Participants

Reaction Steps

Under nitrogen atmosphere and under dry ice-acetone cooling, tert-butyl lithium (64.0 ml; 1.42 mol/L n-pentane solution) was added to THF (150 ml), then, mesityl bromide (6.57 ml) was added dropwise over 2 minutes. The solution was stirred for one hour under the same conditions. 4.07 g of 2-methoxy-5-methylpyridine was added dropwise to the solution over 3 minutes and then the reaction mixture was stirred under ice cooling for one hour and at room temperature for 30 minutes. The solution was dry ice-acetone-cooled again, a suspension of 3.00 g of 5-chloroisatin in THF (75 ml) was added dropwiseover 2 minutes, then the reaction mixture was warmed to room temperature and was stirred for 18 hours. To the reaction solution was added a saturated aqueous solution of NH4Cl and EtOAc, then liquid separation was performed, the aqueous layer was extracted with EtOAc, the combined organic layer was washed with saturated brine, dried over MgSO4, then, the drying agent was separated by filtration, and the filtrate was concentrated under reduced pressure. The obtained residue was purified by column chromatography (silicagel 60; mobile phase: CHCl3/MeOH/NH4OH=97/3/0.3; v/v/v) to obtain 2.05 g of the title compound (yellow solid).

Provenance & Evidence