Maleimide → 4-(Tert.-butyloxycarbonylamino)-1,3-dioxo-1,3,3a,4,7,7a-hexahydroisoindole

Participants

Reaction Steps

48.0 g (0.5 mol) of maleimide dissolved in 200 ml of absolute tetrahydrofuran are introduced into a reaction vessel, and 120 g (0.5 mol) of approx. 70% 1-(tert.-butyloxycarbonylamino)-1,3-butadiene dissolved in 500 ml of absolute tetrahydrofuran are added dropwise, during which process the temperature is kept at 20° to 30° C. Stirring is continued overnight at room temperature. The mixture is then concentrated, and the product is recrystallised from ethyl acetate. 57 g of product of a melting point of 177° to 182° C. are obtained. A further 13 g of a melting point of 158° to 160° C. are obtained from the mother liquor.

Provenance & Evidence