反应详情

温度

60 °C

24.16 g of a bisazomethine prepared from 2 mols of p-hydroxybenzaldehyde and 1 mol of ethylenediamine and with a melting point of 215°-216° C. (decomposition) are hydrogenated in 150 ml of glacial acetic acid with 0.5 g of 10% platinum/charcoal at 25° C. in a hydrogenation flask. After 24 hours no further H2 is taken up. The catalyst is filtered off and the filtrate is concentrated in a rotary evaporator. The residue is crystalline and is stirred with 90 ml of isopropanol at 60° C.; the crystals do not dissolve. They are filtered off at room temperature, washed with isopropanol, and dried at 80° C. in vacuo. Yield 30.65 g (86.8% of theory) of the diacetate of N,N'-bis-(4-hydroxybenzyl)-1,2-diaminoethan with a melting point of 152°-155° C. The NMR spectrum confirms the structure of the diacetate.

1. filtrationThe catalyst is filtered off
2. concentrationthe filtrate is concentrated in a rotary evaporator
3. dissolutionthe crystals do not dissolve
4. filtrationThey are filtered off at room temperature
5. washwashed with isopropanol
6. customdried at 80° C. in vacuo