Dimethylformamide → 2-Ethylthiophene-3-carbaldehyde

HRID 1290238ノート

反応式

HRID 1290238 の反応式
Br[C:2]1[CH:6]=[CH:5][S:4][C:3]=1[CH2:7][CH3:8].[Li]CCCC.CN([CH:17]=[O:18])C>C(OCC)C>[CH2:7]([C:3]1[S:4][CH:5]=[CH:6][C:2]=1[CH:17]=[O:18])[CH3:8]

参加物

5

反応物 3

HCID 6228DimethylformamideHCID 1217473991297-41-5HCID 178418339Butyllithium

生成物 1

HCID 64307212-Ethylthiophene-3-carbaldehyde収率 25%

試薬・触媒・溶媒 1

HCID 3283Diethyl Ether溶媒

反応条件

温度
-78 °C

実験手順

A solution of 3-bromo-2-ethylthiophene, A7, (8.9 g, 0.0465 mol) in 50 mL of diethyl ether was cooled to -78° C., and a solution of n-BuLi (29.0 mL, 1.6M) in hexanes was added dropwise. When the addition was complete, the reaction was stirred at -78° C. for 5 min. Then DMF (5.1 g, 0.070 mol) was cannulated into the reaction mixture which was allowed to warm to ambient temperature and was stirred overnight. The reaction was quenched with water and extracted twice with diethyl ether. The organic extracts were combined, washed with twice with water and then brine and dried (MgSO4). The solution was filtered and concentrated to provide an oil which was purified on flash silica gel with 97.5:2.5 hexanes:diethyl ether to give 1.66 g (25%) of 2-ethylthiophene-3-carboxaldehyde, B7. The 1H NMR in CDCl3 supported the desired product structure. ##STR55##

後処理

  1. additionWhen the addition
  2. temperatureto warm to ambient temperature
  3. stirringwas stirred overnight
  4. customThe reaction was quenched with water
  5. extractionextracted twice with diethyl ether
  6. washwashed with twice with water
  7. dry with materialbrine and dried (MgSO4)
  8. filtrationThe solution was filtered
  9. concentrationconcentrated
  10. customto provide an oil which
  11. customwas purified on flash silica gel with 97.5:2.5 hexanes

出典と根拠

ORDレコード
ord-2229459f21de4acc83888b1ca5918ff2
出典データセット
uspto-grants-1998_05
特許番号
US05750720

反応ノート

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