Acetic Anhydride → 4-Tert-butylcinnamic acid

Participants

Reaction Steps

A 3 L one neck flask fit with a reflux condenser, magnetic stirrer, and nitrogen inlet was charged with p-t-butylbenzaldehyde (145.5 g, 0.90 mol), acetic anhydride (106 mL, 1.12 mol), and sodium acetate (7.36 g, 0.90 mol). After refluxing for 48.5 hours the reaction was cooled and water was added slowly to roughly triple the total volume as a yellow solid formed. The solids were filtered and washed with water (200 mL), reslurried in water and refiltered and washed again with water (750 mL total). The product was partially dried in the vacuum oven to give 4-t-butlycinnamic acid (248 g). 1HNMR (CD3SOCD3, 500 MHz) mostly trans isomer δ7.58 (d, JAB=8.5 Hz, 2H); 7.54 (d, J=15.5 Hz, 1H); 7.41 (d, JAB=7.5 Hz, 2H); 6.46 (d, J=16.0 Hz, 1H); 1.26 (s, 9H).

Provenance & Evidence