Hydrochloric Acid → racemic-3,4-dihydro-7-(phenylmethoxy)-2H-1-benzopyran-2-carboxaldehyde

HRID 2231921ノート

反応式

HRID 2231921 の反応式
C([O:3][C:4]([CH:6]1[CH2:11][CH2:10][C:9]2[CH:12]=[CH:13][C:14]([O:16][CH2:17][C:18]3[CH:23]=[CH:22][CH:21]=[CH:20][CH:19]=3)=[CH:15][C:8]=2[O:7]1)=O)C.C(=O)=O.CC(C)=O.[H-].C([Al+]CC(C)C)C(C)C.Cl>C1(C)C=CC=CC=1.CO>[C:18]1([CH2:17][O:16][C:14]2[CH:13]=[CH:12][C:9]3[CH2:10][CH2:11][CH:6]([CH:4]=[O:3])[O:7][C:8]=3[CH:15]=2)[CH:19]=[CH:20][CH:21]=[CH:22][CH:23]=1

参加物

7

反応物 4

HCID 313Hydrochloric AcidHCID 11162736Ethyl 7-(Benzyloxy)chroman-2-carboxylateHCID 18522661Acetone cardiceHCID 21225700Diisobutylaluminumhydride

生成物 1

HCID 14541228racemic-3,4-dihydro-7-(phenylmethoxy)-2H-1-benzopyran-2-carboxaldehyde収率 94.9%

試薬・触媒・溶媒 2

HCID 887Methanol溶媒HCID 1140Toluene溶媒2 回

実験手順

The ether ester product from example 82 (6.9 g, 22 mmoles) was dissolved in 70 ml of toluene and the solution was cooled to -78° C. (dry-ice-acetone bath). With stirring, 15.6 ml of a 25% solution of diisobutylaluminum hydride in toluene was added dropwise. The reaction mixture was stirred at -78° C. for 2 hours whereupon 2.5 ml of methanol was cautiously added followed by 2N HCl and ice. The mixture was extracted with ethyl acetate and the organic extracts were combined, washed with saturated brine, dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure. The residue (7.6 g) was chromatographed on silica gel. Elution with 9:1 toluene-ethyl acetate gave 5.6 g (70%) of racemic-3,4-dihydro-7-(phenylmethoxy)-2H-1-benzopyran-2-carboxaldehyde as a pale yellow oil.

後処理

  1. additionwas cautiously added
  2. extractionThe mixture was extracted with ethyl acetate
  3. washwashed with saturated brine
  4. dry with materialdried over anhydrous magnesium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated under reduced pressure
  7. customThe residue (7.6 g) was chromatographed on silica gel
  8. washElution with 9:1 toluene-ethyl acetate

出典と根拠

ORDレコード
ord-66b4417b00d740f3bd41322241a9ef8b
出典データセット
uspto-grants-1988_11
特許番号
US04785017

反応ノート

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