反应详情

30 g of Z-Val-Val-OMe (prepared as in Chem. Ber. 103, 788-798 (1970)) are dissolved in 250 ml of methanol and subjected to catalytic hydrogenation at pH 4 after adding methanolic hydrochloric acid and Pd-on-BaSO4. When the reaction is complete, the catalyst is filtered off and the filtrate is concentrated. The resulting oil is triturated with ether. The substance crystallizes after a little time. It is filtered off and rinsed with ether. The substance is hygroscopic and is dried over P2O5 in vacuo. Yield 18.8 g, melting point 153°. [α]D23 =+2.5° (c=1, in methanol).

1. filtrationthe catalyst is filtered off
2. concentrationthe filtrate is concentrated
3. customThe resulting oil is triturated with ether
4. customThe substance crystallizes after a little time
5. filtrationIt is filtered off
6. washrinsed with ether
7. dry with materialis dried over P2O5 in vacuo
8. custom[α]D23 =+2.5° (c=1, in methanol)