Hydrochloric Acid → tert-butyl N-(6-chloro-3-formylpyridin-2-yl)carbamate

Participants

Reaction Conditions

Reaction Steps

The reaction takes place under argon, the apparatus is heat-dried and operated with a KPG stirrer. 15 g (65.6 mmol) of tert-butyl (6-chloropyridin-2-yl)carbamate (Example 25A) and 19 g (164 mmol) of 1,2-bis(dimethylamino)ethane are introduced into 270 ml of THF and cooled to −78° C. 102.5 ml (164 mmol) of butyllithium (1.6N) are added dropwise. After the dropwise addition is complete, the reaction is slowly warmed to −10° C. and kept at −10° C. for 2 h and then cooled again to −78° C., and 10 ml (131 mmol) of DMF are added. The reaction is slowly warmed to RT, and the reaction mixture is added to 1 l of ethyl acetate and 350 ml of 1N hydrochloric acid and stirred for 15 min, and the organic phase is separated off. It is washed with water and saturated sodium bicarbonate solution, dried over magnesium sulphate and concentrated in a rotary evaporator. The residue is mixed with diethyl ether and the solid is filtered off with suction and dried. 12.3 g (73% of theory) of the product are obtained as a solid.

Provenance & Evidence