Acetic Acid → 6-Bromo-3,4-dihydro-4-methyl-2(1H)-quinoxalinone

HRID 44188ノート

反応式

HRID 44188 の反応式
[Br:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[NH:8][C:7](=[O:12])[CH2:6][NH:5]2.C=O.O.[C:16](O)(=O)C.[BH3-]C#N.[Na+]>CO>[Br:1][C:2]1[CH:3]=[C:4]2[C:9](=[CH:10][CH:11]=1)[NH:8][C:7](=[O:12])[CH2:6][N:5]2[CH3:16]

参加物

7

反応物 5

HCID 176Acetic AcidHCID 712FormaldehydeHCID 962WaterHCID 5003444Sodium cyanoborohydrideHCID 669113076-Bromo-1,2,3,4-tetrahydroquinoxalin-2-one

生成物 1

HCID 226677406-Bromo-3,4-dihydro-4-methyl-2(1H)-quinoxalinone収率 94%

試薬・触媒・溶媒 1

HCID 887Methanol溶媒

実験手順

To a solution of 6-bromo-3,4-dihydroquinoxalin-2(1H)-one (370 mg, 1.63 mmol) in 10 ml methanol was added a solution of 37% formaldehyde in water (59 mg, 1.95 mmol) and acetic acid (196 mg, 3.26 mmol). The mixture was stirred at room temperature for 2 h, then refluxed for 1 h. After addition of NaBH3CN (307 mg, 4.89 mmol) stirring was continued for 2.5 h at room temperature. Then methanol was removed under vacuum. To the remaining mixture water was added. Then the solution was basified to pH 8-9 with an aqueous solution of sodium hydrogen carbonate and extracted several times with ethyl acetate. The combined organic layers were washed with brine, dried over MgSO4 and evaporated, affording 6-bromo-4-methyl-3,4-dihydroquinoxalin-2(1H)-one (369 mg, 1.53 mmol, 94%) as off-white solid.

後処理

  1. temperaturerefluxed for 1 h
  2. stirringstirring
  3. waitwas continued for 2.5 h at room temperature
  4. customThen methanol was removed under vacuum
  5. additionTo the remaining mixture water was added
  6. extractionextracted several times with ethyl acetate
  7. washThe combined organic layers were washed with brine
  8. dry with materialdried over MgSO4
  9. customevaporated

出典と根拠

ORDレコード
ord-86985e36ee8640a9b09d1aba01aae0b8
出典データセット
uspto-grants-2013_09
特許番号
US08541404B2

反応ノート

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