Propanal → (Z)-Methyl 3-methyl-4-oxobut-2-enoate

Participants

Reaction Steps

3 g (0.025 mol) of di-n-butylamine were added at 20° C. to a stirred mixture of 120 g (1 mol) of methyl 2-methoxy-2-hydroxyacetate and 58 g (1 mol) of propionaldehyde. An exothermic reaction started immediately and the temperature of the reaction mixture rose to about 90° C., and it boiled vigorously. After about 10 min the temperature started to fall again and reached room temperature after about 1.5 h. Distillation of the reaction mixture yielded 66.4 g of methyl 3-formylcrotonate of b.p. 45°-58° C./8-9 mbar, corresponding to a yield of 52%. The trans/cis ratio was determined by gas chromatography to be 91/9.

Provenance & Evidence