反应详情

To a solution of 0.40 g (1.53 mmol) of [4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]acetic acid in 4.0 ml of dioxane was added 0.18 mL (1.73 mmol) of 2-iodopyrazine, 10.3 mg (0.037 mmol) of tricyclohexylphosphine, 13.9 mg (0.015 mmol) of Pd2(dba)3, and 2.0 ml (1.27 M, 2.59 mmol) of aqueous potassium phosphate solution. The resulting suspension was degassed for 10 mins. After 30 min in the microwave at 150° C., the reaction mixture was cooled, acidified with 1N HCl, extracted with ethyl acetate, and washed with brine. The organic layer was dried over Na2SO4, filtered and concentrated in vacuo. Purification by preparative HPLC (5->95% CH3CN/H2O over 15 min, 0.05% added TFA, C18) afforded 0.10 g (32%) of (4-pyrazin-2-ylphenyl)acetic acid. 1H NMR (CD3OD, 400 MHz) 9.1 (s, 1H); 8.66 (t, J=1.74 Hz, 1H); 8.51 (d, J=2.57 Hz, 1H); 8.04 (d, J=8.15 Hz, 2H); 7.46 (d, J=8.15 Hz, 2H); 3.70 (s, 2H). ES-MS M+1=215.1.

1. customThe resulting suspension was degassed for 10 mins
2. temperaturethe reaction mixture was cooled
3. extractionextracted with ethyl acetate
4. washwashed with brine
5. dry with materialThe organic layer was dried over Na2SO4
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customPurification
9. additionby preparative HPLC (5->95% CH3CN/H2O over 15 min, 0.05% added TFA, C18)