Hydrazine hydrate (1:1) → Tert-butyl 3-amino-4-methylbenzoate

The compound (29.3 g, 123 mmol) of step A was dissolved in methanol (500 ml), ferric chloride (FeCl3) (1.73 g, 10.7 mmol) and activated carbon (4.5 g) were added and the mixture was stirred at room temperature. Then, hydrazine monohydrate (20 ml, 412 mmol) was added, and the mixture was heated under reflux for 45 min. The reaction mixture was cooled, filtered through celite, and the solution was concentrated under reduced pressure. The obtained oil was diluted with an ethyl acetate-hexane=1:1 mixed solvent (300 ml), washed with saturated aqueous sodium hydrogen carbonate and saturated brine, and dried over anhydrous magnesium sulfate. The insoluble material was filtered off, and the solution was concentrated under reduced pressure to give the title compound (26.2 g) as a pale-yellow oil.

1. temperaturethe mixture was heated
2. temperatureunder reflux for 45 min
3. temperatureThe reaction mixture was cooled
4. filtrationfiltered through celite
5. concentrationthe solution was concentrated under reduced pressure
6. additionThe obtained oil was diluted with an ethyl acetate-hexane=1:1 mixed solvent (300 ml)
7. washwashed with saturated aqueous sodium hydrogen carbonate and saturated brine
8. dry with materialdried over anhydrous magnesium sulfate
9. filtrationThe insoluble material was filtered off
10. concentrationthe solution was concentrated under reduced pressure

ORD-Eintrag

ord-c57a976f843b46ec9ae2f67e497a12d9

Quelldatensatz

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08513235B2