Reaktion #569789

Reaktionsgleichung

3-(4-chlorophenyl)-4-methyl-4-propoxy-4,5-dihydro-1H-pyrazole-1-carboxamide

4-(trifluoromethyl)phenylisocyanate

2-methanesulfonyloxymethyl-2-propoxy-4'-chloropropiophenone

sodium acetate

acetic acid

hydrazine monohydrate

→

N-(4-trifluoromethylphenyl)-3-(4-chlorophenyl)-4-methyl-4-propoxy-4,5-dihydro-1H-pyrazole-1-carboxamide

Lösungsmittel

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe mixture was refluxed for one hour
2. 2
   Einengenconcentrated in vacuo
3. 3
   Sonstigepartitioned between diethyl ether and water
4. 4
   WaschenThe organic layer was washed with dilute aqueous sodium hydroxide and brine
5. 5
   Trocknendried over anhydrous magnesium sulfate
6. 6
   Filtrationfiltered
7. 7
   Einengenconcentrated to about 25 ml
8. 8
   Filtrationwas filtered
9. 9
   Waschenwashed with diethyl ether and hexanes yielding 3.3 g of the title compound

Vorschrift

To 3.5 g (10 mmole) of 2-methanesulfonyloxymethyl-2-propoxy-4'-chloropropiophenone (Example 96e) in 25 ml of methanol was added 1.5 g (18 mmole) of anhydrous sodium acetate, 2.5 g (41 mmole) of acetic acid and 1.0 g (20 mmole) of hydrazine monohydrate. The mixture was refluxed for one hour, concentrated in vacuo, partitioned between diethyl ether and water. The organic layer was washed with dilute aqueous sodium hydroxide and brine and then dried over anhydrous magnesium sulfate, filtered and concentrated to about 25 ml. To this solution of 3-(4-chlorophenyl)-4-methyl-4-propoxy-4,5-dihydro-1H-pyrazole-1-carboxamide was added 2.1 g (11 mmole) of 4-(trifluoromethyl)phenylisocyanate. After stirring for 1 hour the precipitated solid was filtered and washed with diethyl ether and hexanes yielding 3.3 g of the title compound, a white solid, mp 135°-138° C.

Quelle