反应详情

温度

20 °C

To a solution of 4 g of 2-amino-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridine in 40 mL of 1,2-dimethoxyethane are added 4.26 g of ethyl 3-bromo-2-oxopropionate. The reaction mixture is stirred for 40 hours at 20° C. The precipitate is filtered off by suction, washed with a small amount of 1,2-dimethoxyethane and pentane and then taken up in 50 mL of ethanol and refluxed for 1 hour. The reaction mixture is concentrated to dryness under reduced pressure. The oil obtained is redissolved in ethyl ether and the solution is concentrated under reduced pressure. The solid is filtered off by suction and washed with a small amount of ethyl ether to give 3.78 g of ethyl 6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)imidazo[1,2-a]pyridine-2-carboxylate hydrobromide (1:1) in the form of a white solid.

1. filtrationThe precipitate is filtered off by suction
2. washwashed with a small amount of 1,2-dimethoxyethane and pentane
3. temperaturerefluxed for 1 hour
4. concentrationThe reaction mixture is concentrated to dryness under reduced pressure
5. customThe oil obtained
6. concentrationthe solution is concentrated under reduced pressure
7. filtrationThe solid is filtered off by suction
8. washwashed with a small amount of ethyl ether