Reaktion #2374048

Reaktionsgleichung

3,4-Dihydro-2-trichloromethyl-2H-benzo[e]-[1,3]-oxazin-4-one

sodium hydroxide

Iodomethane

→

3,4-dihydro-3-methyl-2-trichloromethylbenzo[e]-[1,3]-oxazin-4-one

Lösungsmittel

ethanol

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigeto obtain a clear solution
2. 2
   Temperaturunder reflux for 30 minutes
3. 3
   SonstigeThe solvents were evaporated
4. 4
   workup.DISSOLUTIONthe residue was dissolved in a mixture of toluene and ethyl acetate (7:3 by volume)
5. 5
   Sonstigechromatographed on silica
6. 6
   Wascheneluting with the same solvent mixture
7. 7
   Sonstigeof eluate was collected
8. 8
   Sonstigethe solvent was evaporated
9. 9
   Sonstigethe residue crystallised on trituration with petroleum ether (b.p. 60°-80° C.)

Vorschrift

3,4-Dihydro-2-trichloromethyl-2H-benzo[e]-[1,3]-oxazin-4-one (prepared as described in Example 3--5 g.) was suspended in ethanol (100 ml.), 63 ml. of a solution of sodium hydroxide (1.0 g.) in ethanol (83 ml.) was added, and the mixture was stirred for 15 minutes to obtain a clear solution. Iodomethane (5 ml.) was added, and the solution was boiled under reflux for 30 minutes. The solvents were evaporated, and the residue was dissolved in a mixture of toluene and ethyl acetate (7:3 by volume) and chromatographed on silica, eluting with the same solvent mixture. The first 100 ml. of eluate was collected, the solvent was evaporated and the residue crystallised on trituration with petroleum ether (b.p. 60°-80° C.) to give 3,4-dihydro-3-methyl-2-trichloromethylbenzo[e]-[1,3]-oxazin-4-one, m.p. 82°-84° C.

Quelle