反应详情

温度

-19 °C

To a suspension of 0.25 g (0.93 mmol) of ethyl 7-bromoimidazo[1,2-a]pyridine-2-carboxylate, prepared according to the protocol described in step 8.1, in 4 mL of anhydrous dichloromethane, stirred at −19° C. under an inert atmosphere, are added dropwise 2.09 mL (2.09 mmol) of a molar solution of DIBAL-H in toluene. The reaction mixture is stirred at −19° C. for 3 hours and then hydrolysed at −40° C. by successive addition of 0.1 mL of methanol, 0.1 mL of water and 10 mL of 5N HCl. The reaction mixture is then basified with aqueous sodium hydroxide solution (24%) and then extracted with three times 100 mL of dichloromethane. The combined organic phases are dried over sodium sulfate and then concentrated under reduced pressure. The crude reaction product is then purified by chromatography on a column of silica gel, eluting with a mixture of dichloromethane and methanol. 110 mg of the expected product are thus obtained.

1. customprepared
2. stirringThe reaction mixture is stirred at −19° C. for 3 hours
3. extractionextracted with three times 100 mL of dichloromethane
4. dry with materialThe combined organic phases are dried over sodium sulfate
5. concentrationconcentrated under reduced pressure
6. customThe crude reaction product
7. customis then purified by chromatography on a column of silica gel
8. washeluting with a mixture of dichloromethane and methanol