反应详情

温度

35 °C

Ten grams (10 g, 48.7 mmol) of 2,2-dimethyl 6-nitro 2H-1-benzopyran (3) was dissolved in 60.0 g of ethanol under heating. After cooling to 35° C., 0.6 g of 2% Pt—C (50% water-containing product) was added thereto, and 5.85 g (117.0 mmol) of hydrazine monohydrate (98% product) was added dropwise (dropwise adding was continued for 30 minutes) while controlling internal temperature to 40° C. or less. After completion of dropwise adding, reaction was carried out at a temperature of 40 to 45° C. for 6 hours. The resulting solution was cooled to room temperature, and then 10.0 g of water was added thereto and the resulting solution was filtered through celite. The celite was washed with 20.0 g of 80% water-containing ethanol, and the washing together with the filtrate were subjected to solvent-distillation. The residue was extracted with 40.0 g of toluene and 20.0 g of water. After separating into phases, the aqueous phase was extracted with 20.0 g toluene again. The toluene phases were combined, washed with 20.0 g of water and then subjected to solvent-distillation to obtain a crude product of intended product (4).

1. temperatureunder heating
2. additiondropwise adding
3. customto 40° C. or less
4. additionAfter completion of dropwise adding
5. customreaction
6. waitwas carried out at a temperature of 40 to 45° C. for 6 hours
7. temperatureThe resulting solution was cooled to room temperature
8. filtrationthe resulting solution was filtered through celite
9. washThe celite was washed with 20.0 g of 80% water-
10. additioncontaining ethanol
11. distillationthe washing together with the filtrate were subjected to solvent-distillation
12. extractionThe residue was extracted with 40.0 g of toluene and 20.0 g of water
13. customAfter separating into phases
14. extractionthe aqueous phase was extracted with 20.0 g toluene again
15. washwashed with 20.0 g of water
16. distillationsubjected to solvent-distillation