Potassium Phosphate, Tribasic → Tert-butyl (5-cyclopropylpyridin-3-yl)methylcarbamate
Reaction equation
Br[C:2]1[CH:3]=[C:4]([CH2:8][NH:9][C:10](=[O:16])[O:11][C:12]([CH3:15])([CH3:14])[CH3:13])[CH:5]=[N:6][CH:7]=1.[CH:17]1(B(O)O)[CH2:19][CH2:18]1.P([O-])([O-])([O-])=O.[K+].[K+].[K+].C1(P(C2CCCCC2)C2CCCCC2)CCCCC1>C1(C)C=CC=CC=1.O.C([O-])(=O)C.[Pd+2].C([O-])(=O)C>[CH:17]1([C:2]2[CH:3]=[C:4]([CH2:8][NH:9][C:10](=[O:16])[O:11][C:12]([CH3:15])([CH3:14])[CH3:13])[CH:5]=[N:6][CH:7]=2)[CH2:19][CH2:18]1Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 3
Conditions
- Temperature
- 100 °C
Procedure
To a solution of tert-butyl (5-bromopyridin-3-yl)methylcarbamate (496 mg, 2 mmol), cyclopropyl boronic acid (223 mg, 2.6 mmol), potassium phosphate (1.49 g, 7.0 mmol) and tricyclohexyl phosphine (56 mg, 0.2 mmol) in toluene (9 mL) and water (0.45 mL) under a nitrogen atmosphere was added palladium acetate (22 mg, 0.1 mmol). The mixture was heated at 100° C. for 3 h and then cooled to rt. Water (20 mL) was added and the mixture extracted with EtOAc (2×30 mL), the combined organic extracts were washed with brine (20 mL), dried over Na2SO4 and concentrated in vacuo. Crude product was purified by column chromatography (50% EtOAc in hexanes) afforded tert-butyl (5-cyclopropylpyridin-3-yl)methylcarbamate in 60% yield. (5-cyclopropylpyridin-3-yl)methanamine was then generated by removal of the Boc protecting group by treatment with HCl (in methanol or dioxane) or trifluoroacetic acid in dichloromethane.
Workup
- temperaturecooled to rt
- extractionthe mixture extracted with EtOAc (2×30 mL)
- washthe combined organic extracts were washed with brine (20 mL)
- dry with materialdried over Na2SO4
- concentrationconcentrated in vacuo
- customCrude product was purified by column chromatography (50% EtOAc in hexanes)
Sources & evidence
- ORD record
- ord-630338b639804e95a5a63921ec67b9b8
- Source dataset
- uspto-grants-2012_10
- Patent number
- US08299267B2
Reaction notes
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