Reaktion #77521

Reaktionsgleichung

(3S)-5-(2-chloro-2-propenyl)-3-(hydroxymethyl)-2,3-dihydro-1,4-benzodioxin-6-ol

Potassium carbonate

→

title compound

[8-Methyl-2,3-dihydrofuro[3,2-f][1,4]benzodioxin-2-yl]methanol

Lösungsmittel

trifluoroacetic acid

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe solvent was then removed in vacuum
2. 2
   FiltrationThe mixture was then filtered
3. 3
   Einengenthe filtrate concentrated to a brown residue in vacuum
4. 4
   Sonstigechromatographed on silica gel with methylene chloride as eluant

Vorschrift

A solution of 0.40 g (1.6 mmole) of (3S)-5-(2-chloro-2-propenyl)-3-(hydroxymethyl)-2,3-dihydro-1,4-benzodioxin-6-ol in 70 mL of trifluoroacetic acid was stirred at room temperature for 26 hours. The solvent was then removed in vacuum and replaced with 100 mL of methanol. Potassium carbonate (3.0 g, 2.2 mmole) was added and the mixture stirred for an additional 1.5 hours at room temperature. The mixture was then filtered and the filtrate concentrated to a brown residue in vacuum. The residue was column chromatographed on silica gel with methylene chloride as eluant to give 0.20 g (60%) of the (S)-enantiomer of the title compound as a yellow oil. 1H-NMR (d6-DMSO): doublet 6.94 δ (1H); doublet 6.71 δ (1H); singlet 6.48 δ (1H); triplet 5.07 δ (1H); doublet of doublets 4.30 δ (1H); multiplet 4.22 δ (1H); multiplet 4.00 δ (1H); multiplet 3.65 δ (2H); singlet 2.38 δ (3H).

Quelle