Hydrochloric Acid → 4-Pyridineethanol, 2-chloro-6-(trifluoromethyl)-

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

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.

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