反应详情

温度

-78 °C

2-Chloro-4-iodo-6-(trifluoromethyl)pyridine (0.50 g, 1.6 mmol, European Journal of Organic Chemistry, (18), 3793-3798, 2004) was dissolved in tetrahydrofuran (9.0 mL) and cooled to −78° C. 2.5 M n-Butyllithium in hexanes (0.98 mL, 2.4 mmol) was added dropwise. The reaction was stirred at −78° C. for 45 minutes, at which time 1,3,2-dioxathiolane 2,2-dioxide (0.24 g, 2.0 mmol, Aldrich) in Tetrahydrofuran (2.2 mL) was added. The mixture was then allowed to warm to ambient temperature and stir over 1.5 hours. 12.0 M hydrogen chloride in water (0.81 mL, 9.8 mmol) was added to the mixture and the reaction was stirred overnight. 1N NaOH was then added to achieve a pH between 8 and 9, and brine was also added. The product was extracted with EtOAc, and the organic layer was dried over sodium sulfate, filtered and concentrated. Flash chromatography using a 40 g silica gel cartridge, eluting with a gradient from 0-40% EtOAc in hexanes afforded product as a mixture of isomers, which contained about 50% of the desired isomer (0.09 g, 24%). LCMS (M+H)+: 226.0/228.1.

1. additionwas added
2. temperatureto warm to ambient temperature
3. stirringthe reaction was stirred overnight
4. additionwas also added
5. extractionThe product was extracted with EtOAc
6. dry with materialthe organic layer was dried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated
9. washeluting with a gradient from 0-40% EtOAc in hexanes afforded product as a mixture of isomers, which