反应详情

To a suspension of 1,3-dimethyl-4-(4-methyl-1-cyclohexen-1-yl)-5-(1H)-pyrazolamine (24.5 g; 0.119 mole) in 99% formic acid (245 ml), acetic acid anhydride (64.14 g, 0.628 mole) is added at a temperature of about 20° C. Then the mixture is heated to 80°-90° C. and kept at this temperature for about 2 hours. After distillation of the solvent under vacuum, the residue is taken up with water and the pH is adjusted to about 8 with aqueous sodium carbonate. The solution is extracted with methylene chloride and the organic layer is washed with water and then dried over sodium sulfate. After distillation of the solvent, the crude product of the title is recovered and crystallized from the mixture t.butylmethyl-ether and hexane. M.p. 97°-99° C.

1. additionis added at a temperature of about 20° C
2. temperatureThen the mixture is heated to 80°-90° C.
3. distillationAfter distillation of the solvent under vacuum
4. extractionThe solution is extracted with methylene chloride
5. washthe organic layer is washed with water
6. dry with materialdried over sodium sulfate
7. distillationAfter distillation of the solvent
8. customthe crude product of the title is recovered
9. customcrystallized from the mixture t