Dimethylformamide → 3-(Methylthio)picolinaldehyde

HRID 983638ノート

反応式

HRID 983638 の反応式
CN(CCN(C)C)C.[Li]CCCC.[CH3:14][S:15][C:16]1[CH:17]=[N:18][CH:19]=[CH:20][CH:21]=1.CN([CH:25]=[O:26])C.C(=O)(O)[O-].[Na+]>C(OCC)C>[CH3:14][S:15][C:16]1[C:17]([CH:25]=[O:26])=[N:18][CH:19]=[CH:20][CH:21]=1

参加物

7

反応物 5

HCID 6228DimethylformamideHCID 8037N,N,N',N'-TetramethylethylenediamineHCID 140425Pyridine, 3-(methylthio)-HCID 516892Sodium BicarbonateHCID 178418339Butyllithium

生成物 1

HCID 139052313-(Methylthio)picolinaldehyde収率 19.4%

試薬・触媒・溶媒 1

HCID 3283Diethyl Ether溶媒2 回

反応条件

温度
-78 °C

実験手順

To a cold (−78° C.) stirred solution of TMEDA (0.60 mL, 4.0 mmol) in dry diethyl ether (15 mL) was added a 2.5 M solution of nBuLi in hexanes (1.6 mL, 4.0 mmol). The resulting mixture was stirred 30 min at −78° C., at which point a solution of 3-(methylthio)pyridine (prepared as described by Trecourt, F.; Breton, G.; Bonnet, V.; Mongin, F.; Marsais, F.; Queguiner, G. Tetrahedron 2000, 56, 1349-1360) (500 mg, 4.0 mmol) in dry diethyl ether (5 mL) was added dropwise. The resulting red/orange solution was stirred 2 h at −78° C., then neat DMF (0.31 mL, 4.4 mmol) was added dropwise and stirring was continued for a further 2 h. Saturated aqueous sodium bicarbonate (20 mL) was added, then the phases were separated and the aqueous layer was extracted with CH2Cl2 (3×30 mL). The combined organic extracts were dried (MgSO4), and concentrated in vacuo. Purification of the crude material thus obtained by flash chromatography (silica gel, 4:1 hexanes-EtOAc) afforded 119 mg (19%) of 3-methylsulfanyl-pyridine-2-carbaldehyde. 1H NMR (CDCl3) □ 2.45 (s, 3H), 7.42 (dd, 1H, J=8, 5 Hz), 7.67 (d, 1H, J=9 Hz), 8.50-8.52 (m, 1H), 10.14 (s, 1H).

後処理

  1. additionwas added dropwise
  2. stirringstirring
  3. waitwas continued for a further 2 h
  4. customthe phases were separated
  5. extractionthe aqueous layer was extracted with CH2Cl2 (3×30 mL)
  6. dry with materialThe combined organic extracts were dried (MgSO4)
  7. concentrationconcentrated in vacuo
  8. customPurification of the crude material
  9. customthus obtained by flash chromatography (silica gel, 4:1 hexanes-EtOAc)

出典と根拠

ORDレコード
ord-1bbf0080fc5d41aab8a48663dc0a3d3a
出典データセット
uspto-grants-2005_03
特許番号
US06864265B2

反応ノート

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