Reaktion #318315

Reaktionsgleichung

1-[4,5-(methylenedioxy)-2-(phenylmethoxy)phenyl]ethanone

sodium hydride

dimethylcarbonate

→

methyl 4,5-(methylenedioxy)-β-oxo-2-(phenylmethoxy)benzenepropanoate

Ausbeute 91.3%

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwas heated to 70°-75° C. for 20 minutes
2. 2
   SonstigeAfter evaporating the excess dimethylcarbonate under reduced pressure
3. 3
   Extraktionextracted with ether
4. 4
   WaschenThe ether solution was washed with water
5. 5
   Trocknendried (Na2SO4)
6. 6
   Filtrationfiltered
7. 7
   Einengenconcentrated under reduced pressure
8. 8
   FiltrationThe crude product was filtered through silica gel

Vorschrift

A mixture of 1-[4,5-(methylenedioxy)-2-(phenylmethoxy)phenyl]ethanone (5.4 g, 0.02 mol), sodium hydride (1.6 g of 60% sodium hydride, 0.04 mol) and dimethylcarbonate (18 g, 0.2 mol) was heated to 70°-75° C. for 20 minutes. After evaporating the excess dimethylcarbonate under reduced pressure, the residue was acidified with 10% HCl solution and extracted with ether. The ether solution was washed with water, dried (Na2SO4), filtered and concentrated under reduced pressure. The crude product was filtered through silica gel using chloroform as eluent to afford 5.99 g (91.3%) of methyl 4,5-(methylenedioxy)-β-oxo-2-(phenylmethoxy)benzenepropanoate mp (EtOH) 86°-86.5° C.; IR (KBr) 1750 (ester), 1652 (carbonyl) cm-1 ; NMR (CDCl3, 90 MHz) δ, 3.61 (S, 3H, CO2CH3), 3.92 (S, 2H, CH2CO2CH3), 5.11 (S, 2H, CH2Ph), 5.98 (S, 2H, OCH2O), 6.54 (S, 1H, ArH), 7.39 (S, 5H, CH2Ph), 7.41 (S, 1H, ArH). Anal. calcd. for C18H16O6 : C, 65.85; H, 4.91. Found: C, 65.92; H, 5.11.

Quelle