Hydrochloric Acid → (2E)-4-Methylhepta-2,6-dienoic acid

Participants

Reaction Conditions

Reaction Steps

Malonic acid (99.90 g, 0.96 mol), acetonitrile (285 mL), morpholine (26 mL, 0.30 mol), and pyridine (97 mL, 1.20 mol) were added in this order to the solution of 2-methylpent-4-enal in toluene obtained by the method described above under a nitrogen atmosphere, and the mixture was warmed to 70 to 80° C. and stirred for approximately 21 hours. The reaction mixture was cooled to room temperature. To the reaction mixture, water (380 mL) was added, and concentrated hydrochloric acid (130 mL) was added to separate an organic layer. The aqueous layer was subjected to extraction with toluene (140 mL), and the extract was combined with the organic layer, followed by extractions into aqueous layers with a 2 M aqueous NaOH solution (358 mL) and a 1.3 M aqueous NaOH solution (134 mL) in this order. The aqueous layers were combined and then adjusted to be acidic by the addition of concentrated hydrochloric acid (80 mL), followed by two extractions with toluene (190 mL and 95 mL). The organic layers were combined and then washed with water (95 mL). The organic layer was concentrated under reduced pressure to obtain the title compound (69.05 g, brown oil substance).

Provenance & Evidence