反応式
C(NC(C)C)(C)C.C([Li])CCC.[O:13]1[CH2:17][CH2:16][O:15][CH:14]1[C:18]1[CH:19]=[CH:20][C:21]([F:24])=[N:22][CH:23]=1.[B:25](OC(C)C)([O:30]C(C)C)[O:26]C(C)C>C1COCC1>[O:13]1[CH2:17][CH2:16][O:15][CH:14]1[C:18]1[CH:19]=[C:20]([B:25]([OH:30])[OH:26])[C:21]([F:24])=[N:22][CH:23]=1参加物
反応条件
- 温度
- -78 °C
実験手順
Diisopropylamine (4.60 mL, 32.5 mmol) was dissolved in THF (80 mL) and cooled in an ice water bath. Then, n-butyllithium solution (1.6 M in hexanes, 21.0 mL, 33.6 mmol) was added via syringe. After 30 minutes, the reaction was cooled to −78° C. and 5-(1,3-dioxolan-2-yl)-2-fluoropyridine (3.73 g, 22.1 mmol) was added as a solution in THF (12 mL) dropwise over 5 minutes via syringe, followed by a THF (4 mL) rinse. The reaction was stirred at −78° C. under nitrogen for 1 hour, and then triisopropyl borate (Fluka 98+%, 8.0 mL, 34.9 mmol) was added via syringe, and the reaction was allowed to warm up to room temperature. After 4.5 hours, the reaction was quenched with 1 N NaOH (75 mL). The layers were separated, and the aqueous phase was treated with 5N HCl to lower the pH to between 6 and 7. The aqueous phase was extracted with 10:1 DCM/MeOH. 5N HCl was added to the aqueous phase to lower the pH to about 5, and extraction was continued with 10:1 DCM/MeOH. The organic extracts were combined, concentrated and dried under high vacuum to give 5-(1,3-dioxolan-2-yl)-2-fluoropyridin-3-ylboronic acid (3.165 g, 91% purity, 61% yield over 2 steps). MS (ESI pos. ion) m/z 214 (M+H)+.
後処理
- temperaturecooled in an ice water bath
- washrinse
- temperatureto warm up to room temperature
- waitAfter 4.5 hours
- customthe reaction was quenched with 1 N NaOH (75 mL)
- customThe layers were separated
- additionthe aqueous phase was treated with 5N HCl
- extractionThe aqueous phase was extracted with 10:1 DCM/MeOH
- addition5N HCl was added to the aqueous phase
- extractionto about 5, and extraction
- concentrationconcentrated
- customdried under high vacuum
出典と根拠
- ORDレコード
- ord-48027cb7671e41eeb4da2beef5b04447
- 出典データセット
- uspto-grants-2014_07
- 特許番号
- US08772480B2
関連ノート
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