Acetic Anhydride → 1,3-Hexadien-1-ol acetate

Participants

Reaction Conditions

Reaction Steps

To a mixture of trans-2-hexenal (84.4 g; 0.86 mol) and acetic anhydride (102 g, 1 mol), 8 g (0.065 mol) of 4-dimethylaminopyridine and 105 g (1.04 mol) of triethylamine are added. The mixture is heated to 80° C. for two hours and then, after cooling at room temperature, 200 ml of chloroform is added. The organic layer is washed with two portions of 100 ml of ice-water and then with 30 ml of aqueous sodium bicarbonate. The chloroform layer is dried over MgSO4. Evaporation of the solvent under vacuum yields a residue which is distilled at 80° C./60 mmHg. Yield 106 g. N.M.R. and I.R. Spectrum confirm the assigned structure. The product is a mixture of four isomers containing more than 65% of the Δ-3,4-(E)-isomers.

Provenance & Evidence