Hydrazine hydrate (1:1) → HCID 54175973, compound

3.33 g of N-methyl-N-(4-(tert-butyldimethylsiloxy)-butan-2-yl)-[2-(3,5-dimethoxyphenyl)ethyl]amine was dissolved in 13 ml of tetrahydrofuran to obtain a solution. 13 ml of a solution of tetra-n-butylammonium fluoride in tetrahydrofuran (1 mmol/ml) was slowly added dropwise to the solution. The obtained mixture was stirred at a room temperature for 3 hours and distilled to remove the solvent. The residue was extracted with ether thrice and the ether phase was dried over anhydrous sodium sulfate and concentrated under a reduced pressure. The residue was dissolved in 25 ml of tetrahydrofuran, followed by the addition of 1.29 g of phthalimide and 2.29 g of triphenylphosphine. 1.52 g of diethyl azodicarboxylate was slowly added to the obtained mixture at a room temperature. The obtained mixture was stirred overnight and distilled to remove the solvent. The residue was made acidic with 0.5N hydrochloric acid and washed with ether. The aqueous phase was made basic with lithium hydroxide and extracted with ethyl acetate. The ethyl acetate phase was dried over anhydrous sodium sulfate and the filtrate was concentrated under a reduced pressure to obtain a residue. This residue was dissolved in 20 ml of ethanol, followed by the addition of 200 mg of hydrazine monohydrate. The obtained mixture was heated under reflux for 2 hours and cooled. The white precipitate thus formed was filtered out and the filtrate was concentrated under a reduced pressure, followed by the addition of 20 ml of a 10% solution of sodium hydroxide. The obtained mixture was extracted with chloroform thrice. The chloroform phase was washed with a saturated aqueous solution of common salt, dried over anhydrous sodium sulfate and concentrated under a reduced pressure to obtain 830 mg of the title compound as a yellow oil (yield: 36%).

1. customto obtain a solution
2. distillationdistilled
3. customto remove the solvent
4. extractionThe residue was extracted with ether thrice
5. dry with materialthe ether phase was dried over anhydrous sodium sulfate
6. concentrationconcentrated under a reduced pressure
7. dissolutionThe residue was dissolved in 25 ml of tetrahydrofuran
8. additionfollowed by the addition of 1.29 g of phthalimide and 2.29 g of triphenylphosphine
9. addition1.52 g of diethyl azodicarboxylate was slowly added to the obtained mixture at a room temperature
10. stirringThe obtained mixture was stirred overnight
11. distillationdistilled
12. customto remove the solvent
13. washwashed with ether
14. extractionextracted with ethyl acetate
15. dry with materialThe ethyl acetate phase was dried over anhydrous sodium sulfate
16. concentrationthe filtrate was concentrated under a reduced pressure
17. customto obtain a residue
18. temperatureThe obtained mixture was heated
19. temperatureunder reflux for 2 hours
20. temperaturecooled
21. customThe white precipitate thus formed
22. filtrationwas filtered out
23. concentrationthe filtrate was concentrated under a reduced pressure
24. additionfollowed by the addition of 20 ml of a 10% solution of sodium hydroxide
25. extractionThe obtained mixture was extracted with chloroform thrice
26. washThe chloroform phase was washed with a saturated aqueous solution of common salt
27. dry with materialdried over anhydrous sodium sulfate
28. concentrationconcentrated under a reduced pressure

ORD record

ord-44ad13324d6f47caab9b3cfe1ba4f6df

Source dataset

uspto-grants-1992_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05166188