反应详情

With gentle heating, 22b (5.0 g; 19 mmol) was dissolved in HCl-containing isopropanol (IsOH/HCl-saturated IsOH 1+1, 60 ml). The yellowish solution was cooled to room temperature and transferred into a two-necked flask (100 ml). Pd—C 10% (1.5 g) was introduced into the initial charge. The reaction vessel was evacuated using an oil pump and H2 was then introduced via a gas inlet capillary (4×). At room temperature, the suspension was shaken in a closed three-necked flask under an atmosphere of H2 (240 strokes/min) until no more starting material could be detected by thin-layer chromatography (6.5 h). The catalyst was filtered off. The filtration residue was washed with plenty of methanol (about 800 ml). The combined filtrates were concentrated and the solid-amorphous residue was dried on an oil pump. The crude product was used without further purification for the next reaction step.

1. customtransferred into a two-necked flask
2. additioninitial charge
3. customThe reaction vessel was evacuated
4. additionwas then introduced via a gas inlet capillary (4×)
5. customcould be detected by thin-layer chromatography (6.5 h)
6. filtrationThe catalyst was filtered off
7. washThe filtration residue was washed with plenty of methanol (about 800 ml)
8. concentrationThe combined filtrates were concentrated
9. customthe solid-amorphous residue was dried on an oil pump
10. customThe crude product was used without further purification for the next reaction step