反应详情

温度

-78 °C

DIBAL-H (3.37 ml, 3.37 mmol) was slowly added to a solution of ethyl 5-chloro-6-iodo-3-pyridinecarboxylate (500 mg, 1.605 mmol) in THF (10 ml) at −78° C. The solution turned yellow and was stirred at that temperature for 3 h and then still in the dry-ice bath allowed to slowly attain room temperature overnight. Next morning, TLC showed starting material remaining. The solution was cooled to −78° C. and DIBAL-H (3.37 ml, 3.37 mmol) was added. 3 h later it was allowed to warm to room temperature and after 2 h starting material was still observed. More DIBAL-H (6.74 ml) was added and the solution stirred at room temperature overnight. Full conversion was observed. Saturated, aqueous NaK-tartrate solution and EtOAc were added. Extraction, drying (MgSO4), filtration, and concentration afforded (5-chloro-6-iodo-3-pyridinyl)methanol (393 mg, 91%) as a brown solid pure enough to be used in the next step.

1. customallowed to slowly attain room temperature overnight
2. custom3 h later it
3. temperatureto warm to room temperature and after 2 h
4. stirringthe solution stirred at room temperature overnight
5. extractionExtraction
6. customdrying
7. filtration(MgSO4), filtration, and concentration