反应详情

Cyclopropyl-methanol (2.2 g, 30.6 mmol, 10.0 eq) was dissolved in dry tetrahydrofuran (10 ml, 20 vol) and potassium tert-butoxide (3.4 g, 30.6 mmol, 10.0 eq) added portion-wise. After stirring for 15 minutes at room temperature 5-bromo-6-(4-fluoro-phenyl)-pyrazine-2-carboxylic acid methyl ester (0.95 g, 3.06 mmol, 1.0 eq) was added drop-wise as a tetrahydrofuran (10 ml) solution. The reaction mixture was stirred overnight at room temperature or until deemed complete by HPLC-MS analysis. The solution was concentrated in vacuo and the residue re-dissolved in ethyl acetate (20 ml). The resulting solution was washed with water (5 ml) and the aqueous phase extracted with ethyl acetate (10 ml). The combined organic phases were dried over magnesium sulphate, filtered and concentrated in vacuo to afford 6-(4-fluoro-phenyl)-5-cyclopropylmethoxy-pyrazine-2-carboxylic acid. Yield=0.89 g (75%).

1. concentrationThe solution was concentrated in vacuo
2. dissolutionthe residue re-dissolved in ethyl acetate (20 ml)
3. washThe resulting solution was washed with water (5 ml)
4. extractionthe aqueous phase extracted with ethyl acetate (10 ml)
5. dry with materialThe combined organic phases were dried over magnesium sulphate
6. filtrationfiltered
7. concentrationconcentrated in vacuo