Sodium Hydroxide → 3-(3,4-Dimethylphenyl)propan-1-amine

A mixture of 18.5 g of the compound obtained in step 1 and 50 ml of thionyl chloride was refluxed for 2 hours, concentrated under a reduced pressure and the residue was dissolved in 100 ml of ethyl ether. The resulting solution was added to a mixture of 200 ml of ethyl ether, 150 ml of water and 50 ml of 30% aqueous ammonia solution with stirring. The organic layer was discarded and the remaining aqueous layer was extracted twice with 150 ml of dichloromethane. The organic solvent was distilled off to obtain a residue which was essentially 3-(3,4-dimethylphenyl)propionamide. This residue dissolved in 150 ml of tetrahydrofuran was added to a mixture of 8.0 g of LiAlH4 and 200 ml of tetrahydrofuran. The resultant mixture was refluxed for 5 hours; then 30 ml of 30% aqueous NaOH solution and 20 ml of water were added thereto. After separating the tetrahydrofuran layer, the solid residue was dissolved in 300 ml of water and extracted twice with 200 ml of ethyl ether. The tetrahydrofuran layer and the ethyl ether extract were combined, and the resulting solution was concentrated under a reduced pressure. The residue so obtained was distilled under a reduced pressure(140° to 150° C., 0.5 mmHg) to obtain 13.4 g of the title compound(yield: 79%).

1. temperaturewas refluxed for 2 hours
2. concentrationconcentrated under a reduced pressure
3. dissolutionthe residue was dissolved in 100 ml of ethyl ether
4. additionThe resulting solution was added to a mixture of 200 ml of ethyl ether, 150 ml of water and 50 ml of 30% aqueous ammonia solution
5. extractionthe remaining aqueous layer was extracted twice with 150 ml of dichloromethane
6. distillationThe organic solvent was distilled off
7. customto obtain a residue which
8. customAfter separating the tetrahydrofuran layer
9. dissolutionthe solid residue was dissolved in 300 ml of water
10. extractionextracted twice with 200 ml of ethyl ether
11. extractionThe tetrahydrofuran layer and the ethyl ether extract
12. concentrationthe resulting solution was concentrated under a reduced pressure
13. customThe residue so obtained
14. distillationwas distilled under a reduced pressure(140° to 150° C., 0.5 mmHg)

ORD-Eintrag

ord-e23e8f10934f4e8eb74007834c3316fd

Quelldatensatz

uspto-grants-1997_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05670546