反应详情

0.14 g (0.44 mmol) of 3,4-dihydro-2,2-dimethyl-3-hydroxy-4-(1-piperidinyl)-6-amino-7-nitro-2H-benzo[b]pyran were dissolved in 23.7 g of ethanol and hydroge gas was blown in the presence of 0.10 g of 5% palladiumcarbon, as a catalyst, for 3 hours at room temperature under one atmospheric pressure while stirring. The reaction liquid was filtered under suction to remove the catalyst therefrom, and the solvent was distilled off to obtain 0.12 g (yield: 95%) of 3,4-dihydro-2,2-dimethyl-3-hydroxy-4-(1-piperidinyl)-6-,7-diamino-2H-benzo[b]pyran as a dark red oil. As being unstable, this oil was directly used in the next diazotization.

1. customThe reaction liquid
2. filtrationwas filtered under suction
3. customto remove the catalyst
4. distillationthe solvent was distilled off