Reaktion #7296

Reaktionsgleichung

acetic anhydride

4-formylbenzonitrile

N-acetylglycine

sodium acetate

→

4-(2-Methyl-5-oxooxazol-4-ylidenemethyl)benzonitrile

Lösungsmittel

Acetone

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturunder reflux for 1 h
2. 2
   workup.STIRRINGwith stirring
3. 3
   Temperaturcooling
4. 4
   workup.STIRRINGThe mixture was stirred at 20° C. for another 1 h
5. 5
   SonstigeTo isolate the product
6. 6
   Waschenwashed with deionized water (75 l), isopropanol (40 l) and methyl-tert-butylether (75 l)
7. 7
   SonstigeThe product was dried under reduced pressure at 40° C

Vorschrift

Acetone (80.0 l) was introduced into a mixture of 4-formylbenzonitrile (15.0 kg, 114.5 mol), N-acetylglycine (19.2 kg, 162.4 mol) and anhydrous sodium acetate (9.4 kg, 114.5 mol) followed by introduction, with stirring, of acetic anhydride (35.0 l, 370.5 mol). The reaction mixture was stirred under reflux for 1 h. The resulting thin yellow suspension was cooled to 50° C. and ice-water (200 l) was added as quickly as possible, with stirring and cooling. The mixture was stirred at 20° C. for another 1 h. To isolate the product, the yellow suspension was pressed onto a centrifuge and washed with deionized water (75 l), isopropanol (40 l) and methyl-tert-butylether (75 l). The product was dried under reduced pressure at 40° C. Yield 18.17 kg (85.7 mol, 75.2% of theory). M.p.: 192–193° C.; MS (DCl): m/z=213 [M+H+]; 1H-NMR (DMSO-d6): δ=2.42 (s, 3H), 7.30 (s, 1H), 7.96 (d, 2H), 8.33 (d, 2H).

Quelle