反应详情

温度

0 °C

In a 100 mL flask containing 2,4-dichloropyrimidin-5-amine (1.0 g, 6.10 mmol) in 16.5 mL of dichloromethane was added acetone (1.062 g, 18.29 mmol). The solution was cooled to 0° C. then a solution of titanium tetrachloride (0.740 mL, 6.71 mmol) in 10 mL of dichloromethane was added slowly. The mixture was stirred at room temperature for 2 hours. Sodium cyanoborohydride (1.150 g, 18.29 mmol) was added in 4 equal portions over 10 minutes and the reaction was stirred at room temperature for 2 hours. The reaction was quenched with water (150 mL) and extracted with t-BuOMe twice. The organic layers were combined, dried with Na2SO4, filtered and concentrated in vacuo. The residue was dissolved in methanol and adsorbed onto silica. The residue was purified on silica gel using 0-10% methanol in dichloromethane as eluent. Relevant fractions were evaporated in vacuo to give 940 mg (74%) of 2,4-dichloro-N-isopropylpyrimidin-5-amine as a pale yellow oil. MS [M+H] Found 206.

1. stirringthe reaction was stirred at room temperature for 2 hours
2. customThe reaction was quenched with water (150 mL)
3. extractionextracted with t-BuOMe twice
4. dry with materialdried with Na2SO4
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. dissolutionThe residue was dissolved in methanol
8. customThe residue was purified on silica gel using 0-10% methanol in dichloromethane as eluent
9. customRelevant fractions were evaporated in vacuo