反应详情

13.3 g (50 mmol) of 4-tert.-butyloxycarbonylamino-1,3-dioxo-1,3,3a,4,7,7a-hexahydro-isoindole (from Example A, method II) are stirred in 166 ml of trifluoroacetic acid at room temperature overnight. The trifluoroacetic acid is then distilled off under 10 mbar and the residue is freed from residues of acid at 50° under a high vacuum. It is then taken up in absolute tetrahydrofuran and the mixture is concentrated in vacuo. The residue is taken up in 100 ml of absolute tetrahydrofuran and the mixture is added dropwise to a solution of 11.3 g (0.3 mol) of lithium aluminium hydride in 300 ml of absolute tetrahydrofuran, under nitrogen. The mixture is then boiled under reflux cooling for 16 hours. After cooling, 11.3 g of water in 34 ml of tetrahydrofuran, 11.3 ml of 10% strength sodium hydroxide solution and 34 ml of water are added dropwise in succession. The precipitate is filtered off with suction and washed with tetrahydrofuran. The filtrate is concentrated and the residue is distilled.

1. distillationThe trifluoroacetic acid is then distilled off under 10 mbar
2. customis freed from residues of acid at 50° under a high vacuum
3. concentrationthe mixture is concentrated in vacuo
4. temperatureunder reflux
5. temperaturecooling for 16 hours
6. temperatureAfter cooling
7. filtrationThe precipitate is filtered off with suction
8. washwashed with tetrahydrofuran
9. concentrationThe filtrate is concentrated
10. distillationthe residue is distilled