反应详情

A 745 mg (5 mmol) portion 2,4-dichloropyrimidine (1) was dissolved in 20 mL EtOH at 0 C. 8-oxa-3-aza-bicyclo[3.2.1]octane hydrochloride (2, 748 mg, 5 mmol) was added followed by the addition of NEt3 (2.1 mL, 15 mmol). The mixture was stirred for 1 hour at ambient temperature. The mixture was concentrated, dissolved in EtOAc and washed with saturated NaHCO3. The aqueous phase was extracted with EtOAc and the combined organic phases were dried (MgSO4), filtered and concentrated. The mixture was purified by silica gel chromatography (20-70% EtOAc in hexanes) to give 1,003 mg (4.4 mmol, 89%) of 3-(2-chloro-pyrimidin-4-yl)-8-oxa-3-aza-bicyclo[3.2.1]octane (3) along with 50 mg (0.22 mmol, 4%) of 3-(4-chloro-pyrimidin-2-yl)-8-oxa-3-aza-bicyclo[3.2.1]octane (4).

1. concentrationThe mixture was concentrated
2. dissolutiondissolved in EtOAc
3. washwashed with saturated NaHCO3
4. extractionThe aqueous phase was extracted with EtOAc
5. dry with materialthe combined organic phases were dried (MgSO4)
6. filtrationfiltered
7. concentrationconcentrated
8. customThe mixture was purified by silica gel chromatography (20-70% EtOAc in hexanes)