Reaktion #990729

Reaktionsgleichung

2-(2-hydroxy-3-methylbutyl)-6-(p-chlorophenyl)-4,5-dihydro-3(2H)-pyridazinone

→

2-(3-methyl-2-oxobutyl)-6-(p-chlorophenyl)-4,5-dihydro-3(2H)-pyridazinone

Lösungsmittel

water

acetic acid

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGto stir at room temperature for about 3 hours
2. 2
   workup.ADDITIONpoured onto about 100 milliliters icewater
3. 3
   ExtraktionThe mixture is extracted twice with 50 milliliters of methylene chloride
4. 4
   Waschenthe organic layer is then washed with 30 milliliters of 2 N sodium hydroxide, water
5. 5
   Trocknendried with anhydrous sodium sulfate
6. 6
   FiltrationAfter filtration and evaporation to an oil
7. 7
   Sonstigethe product is crystallized from ether to 1.3 grams of 2-(3-methyl-2-oxobutyl)-6-(p-chlorophenyl)-4,5-dihydro-3(2H)-pyridazinone, (m.p. 110°-111° C.)

Vorschrift

A solution of 7.0 grams (0.024 mol) of 2-(2-hydroxy-3-methylbutyl)-6-(p-chlorophenyl)-4,5-dihydro-3(2H)-pyridazinone in 2.4 milliliters of acetic acid is cooled with stirring in an icebath, and then over a period of about 5 minutes a solution of 2.2 grams (0.022 mol) of chromium trioxide in 45 milliliters of water is added. The reaction mixture is allowed to stir at room temperature for about 3 hours and then poured onto about 100 milliliters icewater. The mixture is extracted twice with 50 milliliters of methylene chloride and the organic layer is then washed with 30 milliliters of 2 N sodium hydroxide, water, and dried with anhydrous sodium sulfate. After filtration and evaporation to an oil, the product is crystallized from ether to 1.3 grams of 2-(3-methyl-2-oxobutyl)-6-(p-chlorophenyl)-4,5-dihydro-3(2H)-pyridazinone, (m.p. 110°-111° C.)

Quelle