反応式
C([O:4][CH:5]1[C:9]2[CH:10]=[CH:11][CH:12]=[C:13](Br)[C:8]=2[O:7][C:6]1([CH3:16])[CH3:15])(=O)C.C([Li])CCC.[B:22](OC)([O:25]C)[O:23]C>O1CCCC1>[OH:4][CH:5]1[C:9]2[CH:10]=[CH:11][CH:12]=[C:13]([B:22]([OH:25])[OH:23])[C:8]=2[O:7][C:6]1([CH3:16])[CH3:15]参加物
反応条件
- 温度
- -80 °C
実験手順
A stirring solution of 5.7 grams (0.020 mole) of 3-acetoxy-7-bromo-2,3-dihydro-2,2-dimethylbenzofuran in 150 mL of tetrahydrofuran is cooled to -80° C., and 18.2 mL of n-butyllithium in hexanes (2.5 Molar--0.046 mole) is added dropwise during a 15 minute period, while maintaining the reaction mixture temperature at about -80° C. Upon completion of the addition, the reaction mixture is stirred at -80° C. for 15 minutes. After this time, 6.9 mL (0.061 mole) of trimethyl borate is added during a 1 minute period. The reaction mixture is then allowed to warm slowly to ambient temperature during a 3 hour period, where it is stirred for an additional 1 hour. After this time, the reaction mixture is concentrated under reduced pressure to a volume of about 50 mL. The concentrate is then poured into 500 mL of ice-water. The mixture is then made acidic with about 26 mL of aqueous 2N hydrochloric acid. The mixture is filtered, yielding 2,3-dihydro-3-hydroxy2,2-dimethylbenzofuran-7-ylboronic acid.
後処理
- additionUpon completion of the addition
- temperatureto warm slowly to ambient temperature during a 3 hour period
- stirringwhere it is stirred for an additional 1 hour
- concentrationAfter this time, the reaction mixture is concentrated under reduced pressure to a volume of about 50 mL
- additionThe concentrate is then poured into 500 mL of ice-water
- filtrationThe mixture is filtered
出典と根拠
- ORDレコード
- ord-f6f86e26448b48ebaa2e10d325cf80ef
- 出典データセット
- uspto-grants-1997_06
- 特許番号
- US05639753
関連ノート
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