Acetic Anhydride → furo(3,4-b)pyridin-5(7H)-one

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

1.5 g of quinolinic anhydride, 2.3 g of N-octyl-2-methylindole, 10 ml of glacial acetic acid and a mixture of 0.11 g of calcium chloride and 0.14 g of zinc chloride are stirred at 20° C. for 5 hours. 1.6 g of 3-diethylaminophenetole and 2 ml of acetic anhydride are then added, after which the reaction mixture is stirred at 50° C. for 21/2 hours. The product is precipitated with 30% aqueous ammonia, separated from the aqueous phase and recrystallised from isopropanol, affording 3.8 g of the isomer-free 4-azaphthalide compound of the formula (12) of melting point 114°-117° C.

Herkunft & Nachweise