Reaktion #67678

Reaktionsgleichung

(3R,5S)-2-methyl-1-phenylpropan-2-yl 6-chloro-3,5-dihydroxy-hexanoate

2,2-dimethoxypropane

methanesulfonic acid

→

crude title compound

2-methyl-1-phenylpropan-2-yl 2-((4R,6S)-6-(chloromethyl)-2,2-dimethyl-1,3-dioxan-4-yl)acetate

Lösungsmittel

acetone

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe reaction liquid
2. 2
   Waschenwashed successively with a saturated sodium bicarbonate aqueous solution (320 ml)
3. 3
   Sonstigea saturated sodium chloride aqueous solution (320 ml) and purified water (320 ml)
4. 4
   TrocknenThe separated organic layer was dried over anhydrous magnesium sulfate
5. 5
   Einengenconcentrated under reduced pressure

Vorschrift

The crude compound (3R,5S)-2-methyl-1-phenylpropan-2-yl 6-chloro-3,5-dihydroxy-hexanoate (21.1 g) prepared in Example 3 was dissolved in acetone (210 ml), and 2,2-dimethoxypropane (65.6 ml) and methanesulfonic acid (0.2 ml) were added dropwise thereto, followed by stirring at room temperature for 2 hours. The reaction liquid was diluted with ethyl acetate (320 ml) and washed successively with a saturated sodium bicarbonate aqueous solution (320 ml), a saturated sodium chloride aqueous solution (320 ml) and purified water (320 ml). The separated organic layer was dried over anhydrous magnesium sulfate and then concentrated under reduced pressure to give the crude title compound (23.7 g).

Quelle