Reaktion #66431

Reaktionsgleichung

HCl

malonic acid

benzaldehyde

piperidine

→

cinnamic acid

Lösungsmittel

pyridine

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturchilled
2. 2
   Filtrationthe white precipitate collected by filtration
3. 3
   Waschenwashed with 5×10 mL water
4. 4
   Sonstigedried

Vorschrift

To a solution of malonic acid (10.4 g, 0.1 mol) and the benzaldehyde (0.05 mol) in pyridine (20 mL) was added neat piperidine (0.75 mL, 7.6 mmol). The reaction mixture was stirred at 80° C. for 17 hr, chilled, then added to 200 mL cold water. This mixture was acidified with conc. HCl (25 mL) and the white precipitate collected by filtration, washed with 5×10 mL water, and dried to give pure cinnamic acid in typical yields of >95%.

Quelle