Reaktion #546493

Reaktionsgleichung

MsCl

mesylate

Mesyl chloride

acrylate

3-(3-benzyloxy-phenyl)-3-hydroxy-2-methoxy-propionic acid methyl ester

triethylamine

→

3-(3-benzyloxy-phenyl)-2-methoxy-acrylic acid methyl ester

Lösungsmittel

diethyl ether

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwere added each day)
2. 2
   Waschenwashed with HCl (1N, 3×40 mL) and 40 mL of brine
3. 3
   Trocknendried over MgSO4 Concentration of the mixture
4. 4
   Sonstigeafforded 3.96 g

Vorschrift

The compounds of 3-(3-benzyloxy-phenyl)-3-hydroxy-2-methoxy-propionic acid methyl ester (Example 291, Step 1) (4.06 g, 12.84 mmol), triethylamine (7.15 mL, 51.33 mmol) and 4-(N,N-dimethylamino)pyridine (0.157 g, 128 mmol) were dissolved in dichloromethane (20 mL) in a round bottom flask and then cooled to 0° C. under ice bath. Mesyl chloride (1.093 mL, 14.1 mmol) was added dropwise via syringe, and the mixture was stirred at room temperature until no starting aldol is observed by HPLC-MS (4 days, 0.2 additional mL of MsCl were added each day). The mixture was diluted with 200 mL of diethyl ether, washed with HCl (1N, 3×40 mL) and 40 mL of brine, and dried over MgSO4 Concentration of the mixture afforded 3.96 g. of a 2.5:1 mixture of the acrylate and a single isomer of the mesylate intermediate which was directly used in the next Step. 1H-NMR (CDCl3, 200.15 MHz): 7.46–7.26 (m, 8H), 6.99–6.93 (m, 1H), 5.10 (s, 2H), 3.85 (s, 3H), 3.72 (s, 3H).

Quelle