Tetrahydrofuran → Acetone cyclohexane

Participants

Reaction Steps

Initially introduce 83.2 g (1.0 mol) of (E)-1-amino-2,4-pentadiene (title compound from Example B.2.) in 250 ml of THF and add 0.1 g of 4-hydroxyanisole. Subsequently add dropwise 229.2 g (1.05 mol) of di-tert-butyl dicarbonate dissolved in 250 ml of THF at an internal temperature of 20°-30° C. After addition is complete stir at room temperature for 20 h. Add 103.0 g (1.05 mol) of maleic anhydride and heat to reflux for 5 h. Concentrate and take up the residue in 500 ml of methanol, add 30 ml of p-toluenesulphonic acid, then again heat to reflux for 5 h. After cooling, rapidly add dropwise a solution of 20 g of sodium carbonate dissolved in 500 ml of water with ice-cooling and stirring, allow mixture to stand for a further 30 min in the ice bath, filter off precipitate with suction, wash with a little water and dry to constant weight at 50° C.

Provenance & Evidence