反应详情

2.6 Grams of 5% palladium on carbon catalyst was added to a mixture of 260 grams of 5-nitrotetrahydroanthraquinone and 24,000 grams of ethanol, into which was injected hydrogen for absorption in the 5-nitro compound in an amount of 2 mols per mol of the 5-nitro compound at normal (ambient) temperature and under normal atmospheric pressure. The solution which was first pale yellow turned reddish brown in color as the reaction proceeded and a small amount of precipitate appeared in the solution. When the hydrogenation was continued, the solution became almost transparent and dark reddish brown upon completion of the reaction. The hydrogen in the reactor was replaced by nitrogen, to which was added 400 grams of a 20% sodium hydroxide solution and the color of the resultant solution turned dark yellowish brown immediately after the addition of the alkali during which a small amount of glossy crystals were precipitated. The reaction was completed immediately, dark yellowish brown being the color of leuco-1-aminoanthraquinone which is obtained by catalytical hydrogenation of 1-aminoanthraquinone or by having 1 mol of hydrogen absorbed in 1 mol of 1-aminoanthraquinone under the same reaction conditions, and then air was fed into the solution for oxidation. Upon determination, it was found that 0.5 mol of oxygen was absorbed per mol of the 5-nitro compound. As a result, the reaction solution turned reddish orange with a precipitate of a reddish orange color. The resultant solution was subjected to filtration, followed by extraction of the cake with acetone for separation of the catalyst. The resultant filtrate was dried up to obtain 220 grams of 1-aminoanthraquinone having a purity of 98%.

1. customfor absorption in the 5-nitro compound in an amount of 2 mols per mol of the 5-nitro compound at normal (ambient) temperature
2. customthe solution became almost transparent and dark reddish brown upon completion of the reaction
3. additionafter the addition of the alkali during which a small amount of glossy crystals
4. customwere precipitated