反应详情

To a stirred solution of 3.0 grams (0.025 mole) of 3-hydroxy-2,2-dimethylpropionic acid (Example 12, Step A) and 3.9 grams (0.025 mole) of N-(2-chlorophenyl)methyl hydroxylamine (Example 1, Step A-2) in 65 ml of ethanol was added dropwise a solution of 5.2 grams (0.025 mole) of dicyclohexylcarbodiimide in 25 ml of chloroform. Upon completion of addition the reaction mixture was stirred at ambient temperature for 60 hours. The reaction mixture was concentrated under reduced pressure to give a residual solid. The solid was recrystallized from ethanol, then from ethanol-water to give a solid; mp 229°-230°. The filtrates from the recrystallizations were combined and concentrated under high vacuum to give a residual oil. The residual oil was subjected to column chromatography. Elution was accomplished using 4:1--cyclohexane:ethyl acetate. The appropriate fraction was concentrated under reduced pressure to give a solid. The solid was recrystallized from ethyl acetatehexane to give 0.51 gram of N-[(2-chlorophenyl)methyl]-N,3-dihydroxy-2,2-dimethylpropanamide; mp 130°-132°. The solid was recrystallized a second time from ethyl acetate-cyclohexane to raise the mp to 131°-132°.

1. additionUpon completion of addition the reaction mixture
2. concentrationThe reaction mixture was concentrated under reduced pressure
3. customto give a residual solid
4. customThe solid was recrystallized from ethanol
5. customfrom ethanol-water to give a solid
6. customThe filtrates from the recrystallizations
7. concentrationconcentrated under high vacuum
8. customto give a residual oil
9. washElution
10. concentrationThe appropriate fraction was concentrated under reduced pressure
11. customto give a solid
12. customThe solid was recrystallized from ethyl acetatehexane