Reaktion #353305

Reaktionsgleichung

ethyl 2-chloromethyl-4-(3,4-dimethoxyphenyl)-6,7-dimethoxyquinoline-3-carboxylate

m-chloroperbenzoic acid

→

ethyl 2-chloromethyl-4-(3,4-dimethoxyphenyl)-6,7-dimethoxyquinoline-3-carboxylate 1-oxide

Ausbeute 65.0%

Lösungsmittel

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturunder reflux for 2 hours
2. 2
   EinengenThe reaction mixture was concentrated under reduced pressure
3. 3
   workup.DISSOLUTIONThe residue was dissolved in chloroform
4. 4
   WaschenThe chloroform layer was washed with water
5. 5
   Trocknendried over magnesium sulfate
6. 6
   Sonstigethe solvent was evaporated under reduced pressure
7. 7
   WaschenThe fractions eluted with chloroform-ethyl acetate (6:4, v/v)

Vorschrift

A mixture of ethyl 2-chloromethyl-4-(3,4-dimethoxyphenyl)-6,7-dimethoxyquinoline-3-carboxylate (3.0 g), m-chloroperbenzoic acid (85%, 2.3 g) and methanol (40 ml) was stirred under reflux for 2 hours. The reaction mixture was concentrated under reduced pressure. The residue was dissolved in chloroform. The chloroform layer was washed with water and dried over magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was subjected to column chromatography on silica gel. The fractions eluted with chloroform-ethyl acetate (6:4, v/v) gave ethyl 2-chloromethyl-4-(3,4-dimethoxyphenyl)-6,7-dimethoxyquinoline-3-carboxylate 1-oxide (2.0 g, 65%). This was recrystallized from acetone-isopropyl ether. Colorless prisms, mp. 193°-194° C.

Quelle