Reaktion #216240

Reaktionsgleichung

4,7-dimethoxy-5-acetyl-6-hydroxybenzofuran

hydrochloric acid

2-Chloromethyl-4-isopropyl-6-methoxysaccharin

2-chloromethyl-4-isopropyl-6-methoxysaccharin

4,7-dimethoxy-5-acetyl-6-hydroxybenzofuran

methyltriazabicyclodecene

→

2-(4,7-dimethoxy-5-acetylbenzofuran-6-yl)oxymethyl-4-isopropyl-6-methoxysaccharin

Ausbeute 48.3%

Lösungsmittel

acetonitrile

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONa drop of base were added
2. 2
   workup.STIRRINGstirring
3. 3
   Sonstigewas continued for a total of 24 hours
4. 4
   SonstigeThe resulting golden solid was partially purified
5. 5
   workup.STIRRINGwith stirring overnight at 35°-40° C. instead of room temperature
6. 6
   SonstigeThe product and the partially purified product of the first reaction
7. 7
   Sonstigepurified by column chromatography on silica gel

Vorschrift

2-Chloromethyl-4-isopropyl-6-methoxysaccharin (0.5 g) was added with stirring at room temperature to a solution of 4,7-dimethoxy-5-acetyl-6-hydroxybenzofuran (0.39 g) and methyltriazabicyclodecene (0.28 g) in acetonitrile (20 mL). The mixture was stirred overnight at room temperature. Since thin layer chromatography showed unreacted 4,7-dimethoxy-5-acetyl-6-hydroxybenzofuran, more 2-chloromethyl-4-isopropyl-6-methoxysaccharin and a drop of base were added, stirring was continued for a total of 24 hours, and the reaction mixture was poured into ice-water containing hydrochloric acid. The resulting golden solid was partially purified using dichloromethane as eluant The reaction was repeated with stirring overnight at 35°-40° C. instead of room temperature. The product and the partially purified product of the first reaction were combined and purified by column chromatography on silica gel affording 2-(4,7-dimethoxy-5-acetylbenzofuran-6-yl)oxymethyl-4-isopropyl-6-methoxysaccharin (0.4 g, 24% yield).

Quelle