N,N,N',N'-Tetramethylethylenediamine → (2-[(tert-Butoxycarbonyl)amino]pyridin-3-yl)boronic acid
Reaction equation
[N:1]1[CH:6]=[CH:5][CH:4]=[CH:3][C:2]=1[NH:7][C:8](=[O:14])[O:9][C:10]([CH3:13])([CH3:12])[CH3:11].CN(C)CCN(C)C.C([Li])CCC.[B:28](OC(C)C)([O:33]C(C)C)[O:29]C(C)C.[Cl-].[NH4+]>C1COCC1.C(OCC)C>[C:10]([O:9][C:8]([NH:7][C:2]1[C:3]([B:28]([OH:33])[OH:29])=[CH:4][CH:5]=[CH:6][N:1]=1)=[O:14])([CH3:11])([CH3:13])[CH3:12]Participants
Reactant 5
Product 1
Reagents, catalysts & solvents 2
Conditions
- Temperature
- -6 °C
Procedure
Under a nitrogen atmosphere, a solution of tert-butyl N-(2-pyridyl)carbamate (15.71 g, 80.9 mmol) and N,N,N′,N′-tetramethylethylenediamine (TMEDA, 25.3 g, 218 mmol) in THF (400 mL) was cooled to −78° C. n-Butyllithium (81 mL of a 2.5 M solution in hexanes) was added dropwise over a period of 20 minutes. The solution was stirred for ten minutes, and then the addition funnel was rinsed with additional THF (20 mL). The solution was warmed to −6° C., stirred for two hours, and cooled again to −78° C. Triisopropyl borate (57.7 g, 307 mmol) was added over a period of ten minutes. The resulting solution was warmed to 0° C. and then poured into saturated aqueous ammonium chloride (500 mL). A yellow solid formed and was stirred with diethyl ether (300 mL), isolated by filtration, washed with diethyl ether and water, and air-dried overnight to provide 2-tert-butoxycarbonylamino-3-pyridylboronic acid as a yellow solid.
Workup
- additionwas added dropwise over a period of 20 minutes
- washthe addition funnel was rinsed with additional THF (20 mL)
- stirringstirred for two hours
- temperaturecooled again to −78° C
- temperatureThe resulting solution was warmed to 0° C.
- customA yellow solid formed
- customisolated by filtration
- washwashed with diethyl ether and water
- customair-dried overnight
Sources & evidence
- ORD record
- ord-a2529acb59ae435fa561a8e180e6d6bb
- Source dataset
- uspto-grants-2015_09
- Patent number
- US09145410B2
Reaction notes
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