2-Amino-5-chloropyridine → (2S)-3-[3-(tert-butyl-dimethylsilyl)oxyazetidin-1-yl]-N-(5-chloropyridin-2-yl)-2-hydroxypropanamide
Reaction equation
C[Al](C)C.[Cl:5][C:6]1[CH:7]=[CH:8][C:9]([NH2:12])=[N:10][CH:11]=1.[Si:13]([O:20][CH:21]1[CH2:24][N:23]([CH2:25][C@H:26]([OH:31])[C:27](OC)=[O:28])[CH2:22]1)([C:16]([CH3:19])([CH3:18])[CH3:17])([CH3:15])[CH3:14]>C1(C)C=CC=CC=1>[Si:13]([O:20][CH:21]1[CH2:24][N:23]([CH2:25][C@H:26]([OH:31])[C:27]([NH:12][C:9]2[CH:8]=[CH:7][C:6]([Cl:5])=[CH:11][N:10]=2)=[O:28])[CH2:22]1)([C:16]([CH3:19])([CH3:18])[CH3:17])([CH3:15])[CH3:14]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 0 °C
Procedure
Trimethylaluminium (5.75 mL, 11.50 mmol) was added to 5-chloropyridin-2-amine (1.285 g, 10.00 mmol) in toluene (50 mL) cooled to 0° C. under nitrogen. The resulting solution was stirred at 0° C. for 10 minutes, (S)-methyl 3-(3-(tert-butyldimethylsilyloxy)azetidin-1-yl)-2-hydroxypropanoate (Intermediate AD3) (2.894 g, 10.00 mmol) in toluene (20 mL) was added, the reaction allowed to warm to room temperature and then heated at 80° C. for 4 hours. The reaction mixture was cooled, concentrated in vacuo and the residue neutralised with 1M citric acid (30 mL), diluted with water (25 mL) and extracted with EtOAc (2×30 mL). The combined organic extracts were dried (MgSO4) and evaporated to afford crude product which was purified by flash silica chromatography with EtOAc as eluent to afford the product (2.5 g, 65%). 1H NMR (400 MHz, DMSO) δ 0.01 (6H, s), 0.84 (9H, m), 2.65-2.70 (2H, m), 2.76-2.83 (2H, m), 3.56-3.59 (2H, m), 4.07-4.10 (1, m), 4.28-4.34 (1H, m), 5.78 (1H, s), 7.92 (1H, dd), 8.12 (1H, dd), 8.36-8.37 (1H, m), 9.87 (1H, s); m/z (ESI+) (M+H)+=386; HPLC tR=1.64 min.
Workup
- temperatureto warm to room temperature
- temperatureheated at 80° C. for 4 hours
- temperatureThe reaction mixture was cooled
- concentrationconcentrated in vacuo
- additiondiluted with water (25 mL)
- extractionextracted with EtOAc (2×30 mL)
- dry with materialThe combined organic extracts were dried (MgSO4)
- customevaporated
- customto afford crude product which
- customwas purified by flash silica chromatography with EtOAc as eluent
Sources & evidence
- ORD record
- ord-65062b00fc5348ad852d759bed4d85dc
- Source dataset
- uspto-grants-2012_03
- Patent number
- US08143263B2
Reaction notes
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