反应详情

In 10 volume parts of water is dissolved 0.180 part of 3,4-dihydro-2-isopropylamino-5,6-dihydroxy-1(2H)-naphthalenone hydrobromide and with the addition of 0.2 part of 5 % palladium-on-carbon, catalytic reduction is carried out in a current of hydrogen gas. The absorption of hydrogen ceases when 9 volume parts of hydrogen has been absorbed. The catalyst is filtered off and the filtrate is freeze-dried. Finally, the residue is recrystallized from ethanol-ethyl ether. The procedure gives colorless prisms of 1,5,6-trihydroxy-2-isopropylamino-1,2,3,4-tetrahydronaphthalene hydrobromide. Melting point: 169° C.(decomp.)

1. customThe absorption of hydrogen ceases when 9 volume parts of hydrogen
2. customhas been absorbed
3. filtrationThe catalyst is filtered off
4. customthe filtrate is freeze-dried
5. customFinally, the residue is recrystallized from ethanol-ethyl ether