Reaktion #168157

Reaktionsgleichung

4-{(S)-1-[(S)-6-(2-hydroxy-2-methyl-propyl)-2-oxo-6-phenyl-[1,3]oxazin-an-3-yl]-ethyl}-benzoic acid hydrazide

toluene-4-sulfonic acid monohydrate

1,1,1-trimethoxy-ethane

→

title compound

(S)-6-(2-Methyl-allyl)-3-{(S)-1-[4-(5-methyl-[1,3,4]oxadiazol-2-yl)-phenyl]-ethyl}-6-phenyl-[1,3]oxazinan-2-one

Lösungsmittel

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturfinally at reflux temperature for 1.5 h
2. 2
   TemperaturAfter cooling to ambient temperature
3. 3
   Waschenthe resulting mixture was washed with aqueous NaHCO3 solution and brine
4. 4
   SonstigeThe solvent was removed under reduced pressure
5. 5
   Sonstigethe residue was purified by chromatography on silica gel (CH2Cl2/MeOH 99:1→95:5)

Vorschrift

A mixture of 4-{(S)-1-[(S)-6-(2-hydroxy-2-methyl-propyl)-2-oxo-6-phenyl-[1,3]oxazin-an-3-yl]-ethyl}-benzoic acid hydrazide (90 mg), toluene-4-sulfonic acid monohydrate (10 mg), and 1,1,1-trimethoxy-ethane (1 ml) was stirred at room temperature for 1 h, at 80° C. for 2 h, and finally at reflux temperature for 1.5 h. After cooling to ambient temperature, ethyl acetate was added and the resulting mixture was washed with aqueous NaHCO3 solution and brine. The solvent was removed under reduced pressure and the residue was purified by chromatography on silica gel (CH2Cl2/MeOH 99:1→95:5) to afford the title compound as a colorless resin-like solid.

Quelle