Sodium hydride → 2-methyl-6-(tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indole

HRID 1403457ノート

反応式

HRID 1403457 の反応式
Br[C:2]1[CH:10]=[C:9]2[C:5]([CH:6]=[C:7]([CH3:11])[NH:8]2)=[CH:4][CH:3]=1.[H-].[Na+].[Li]CCCC.[CH3:19][C:20]1([CH3:31])[C:24]([CH3:26])([CH3:25])[O:23][B:22](OC(C)C)[O:21]1>O1CCCC1>[CH3:11][C:7]1[NH:8][C:9]2[C:5]([CH:6]=1)=[CH:4][CH:3]=[C:2]([B:22]1[O:23][C:24]([CH3:26])([CH3:25])[C:20]([CH3:31])([CH3:19])[O:21]1)[CH:10]=2

参加物

6

反応物 4

HCID 24758Sodium hydrideHCID 2715546-Bromo-2-methyl-1h-indoleHCID 50177412-Isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolaneHCID 178418339Butyllithium

生成物 1

HCID 706646442-methyl-6-(tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indole収率 49%

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒

反応条件

温度
-40 °C

実験手順

To a solution of 6-bromo-2-methyl-1H-indole (2.0 g, 9.52 mmol) in dry tetrahydrofuran (100 mL) was added sodium hydride (381 mg, 9.53 mmol) with ice-cooling. After stirring for about 30 min, a solution of n-BuLi (15 mL, 2.5 M solution in hexane) was added dropwise with stirring at −78° C. under nitrogen. It was warmed slowly to −40° C. during 45 min and stirred at this temperature for another 30 min. The mixture was cooled again below −78° C. followed by dropwise addition of 4,4,5,5-tetramethyl-2-(propan-2-yloxy)-1,3,2-dioxaborolane (3.54 g, 19.03 mmol). After warming to room temperature, the mixture was quenched with NH4Cl (aq) and extracted with ethyl acetate (3×80 mL). The combined organic layers were dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to give the residue, which was purified by silica gel column chromatography (2% ethyl acetate in petroleum ether) to afford 2-methyl-6-(tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-indole (1.2 g, 49%).

後処理

  1. temperaturecooling
  2. stirringwith stirring at −78° C. under nitrogen
  3. stirringstirred at this temperature for another 30 min
  4. temperatureThe mixture was cooled again below −78° C.
  5. temperatureAfter warming to room temperature
  6. customthe mixture was quenched with NH4Cl (aq)
  7. extractionextracted with ethyl acetate (3×80 mL)
  8. dry with materialThe combined organic layers were dried over anhydrous sodium sulfate
  9. filtrationfiltered
  10. concentrationconcentrated under reduced pressure
  11. customto give the residue, which
  12. customwas purified by silica gel column chromatography (2% ethyl acetate in petroleum ether)

出典と根拠

ORDレコード
ord-4975337309e3446695ea02baaff29d45
出典データセット
uspto-grants-2014_12
特許番号
US08912188B2

反応ノート

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