Hydrazine hydrate (1:1) → [(S)-2-amino-2-(3-chloro-phenyl)-ethyl]-carbamic acid tert-butyl ester
Reaction equation
[Cl:1][C:2]1[CH:3]=[C:4]([C@H:8]([N:18]2C(=O)C3C(=CC=CC=3)C2=O)[CH2:9][NH:10][C:11](=[O:17])[O:12][C:13]([CH3:16])([CH3:15])[CH3:14])[CH:5]=[CH:6][CH:7]=1.O.NN>C(O)C>[NH2:18][C@@H:8]([C:4]1[CH:5]=[CH:6][CH:7]=[C:2]([Cl:1])[CH:3]=1)[CH2:9][NH:10][C:11](=[O:17])[O:12][C:13]([CH3:16])([CH3:15])[CH3:14]Participants
Conditions
- Temperature
- 60 °C
Procedure
To a solution of (S)-tert-butyl (2-(3-chlorophenyl)-2-(1,3-dioxoisoindolin-2-yl)ethyl)carbamate (5.0 g, 12.47 mmol) in ethanol (41.6 mL) was added hydrazine hydrate (6.06 mL, 125 mmol). The reaction mixture was heated at 60° C. for 2 h. The reaction mixture was filtered through Celite pad. The filtrate was concentrated and the residue was diluted with DCM and filtered off through Celite. The same process was repeated until no white precipitate was shown. To remove the white side product completely, the product was dissolved in 1N HCl (30 mL), washed with EtOAc, and the aqueous phase was neutralized to pH 7 then back-extracted by EtOAc. The organic was dried over anhydrous sodium sulfate, filtered off, and concentrated in vacuo yielding (S)-tert-butyl (2-amino-2-(3-chlorophenyl)ethyl)carbamate (89%). LCMS (m/z): 271.1 (MH+), 0.58 min.
Workup
- filtrationThe reaction mixture was filtered through Celite pad
- concentrationThe filtrate was concentrated
- additionthe residue was diluted with DCM
- filtrationfiltered off through Celite
- customTo remove the white side product completely
- dissolutionthe product was dissolved in 1N HCl (30 mL)
- washwashed with EtOAc
- extractionthen back-extracted by EtOAc
- dry with materialThe organic was dried over anhydrous sodium sulfate
- filtrationfiltered off
- concentrationconcentrated in vacuo
Sources & evidence
- ORD record
- ord-61079a0ab3704555a5a4b1a842defd8b
- Source dataset
- uspto-grants-2016_01
- Patent number
- US09242996B2
Reaction notes
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