4-Nitrobenzaldehyde → HCID 23004102, compound

Participants

Reaction Steps

A mixture of 2-cyanoethyl 3-oxohexanoate (11.9 mmol), methyl 3-aminocrotonate (11.9 mmol), and 4-nitrobenzaldehyde in 25 mL of isopropanol were heated at reflux temperature for 16 h, cooled, and the solvent was removed under reduced pressure. The residue was dissolved in 15 mL of dioxane (slightly warmed with a heat gun to dissolve the product) and 626 mg of NaOH in 15 mL of water was added to the reaction mixture. After 0.5 hrs, the maroon solution was concentrated to a small volume under reduced pressure, partitioned between 50 mL of water and 50 mL of ethyl acetate, separated, and the aqueous solution was washed with 2×20 mL of ethyl acetate. The aqueous extract was acidified with concentrated HCl (pH=2), and the precipitated oil was extracted with ethyl acetate (2×40 mL). The combined organic extracts were dried (MgSO4), and the solvent was removed in vacuo to give the desired product as a foamy yellow solid. The acid was used in the next step without further purification.

Provenance & Evidence