Reaktion #217574

Reaktionsgleichung

[(2R)-7-Amino-8-hydroxy-2,3-dihydro-1,4-benzodioxin-2-yl]methyl 4-methyl-benzenesulfonate hydrochloride

p-toluenesulfonic acid

→

title compound

7.8-Dihydro[1,4]dioxino[2,3-g][1,3]benzoxazol-8-ylmethyl 4-methylbenzenesulfonate

Lösungsmittel

trimethyl orthoformate

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe solvent was removed under high vacuum
2. 2
   Sonstigeto yield a beige solid
3. 3
   SonstigeThe crude product was recrystallized from ethanol

Vorschrift

[(2R)-7-Amino-8-hydroxy-2,3-dihydro-1,4-benzodioxin-2-yl]methyl 4-methyl-benzenesulfonate hydrochloride (1.05 g, 2.99 mmole) in trimethyl orthoformate (7 mL) was heated to reflux in the presence of 0.20 g of p-toluenesulfonic acid for 3 hours. The solvent was removed under high vacuum to yield a beige solid. The crude product was recrystallized from ethanol to give 0.81 g (75%) of the (R)-enantiomer of the title compound, MS (ESI) m/z 361 (M+H)+.

Quelle