Dimethylformamide → 3-Hydroxymethyl-5-methyl-2,3-dihydrobenzo[1,4]dioxine-6-carboxylic acid methyl ester

HRID 919008ノート

反応式

HRID 919008 の反応式
[OH:1][C:2]1[C:3]([CH3:13])=[C:4]([CH:9]=[CH:10][C:11]=1[OH:12])[C:5]([O:7][CH3:8])=[O:6].CC1C=CC(S([O:24][CH2:25][C@@H:26]2O[CH2:27]2)(=O)=O)=CC=1.C(=O)([O-])[O-].[K+].[K+].CN(C=O)C>CCOCC>[CH3:8][O:7][C:5]([C:4]1[CH:9]=[CH:10][C:11]2[O:12][CH2:27][CH:26]([CH2:25][OH:24])[O:1][C:2]=2[C:3]=1[CH3:13])=[O:6]

参加物

6

反応条件

温度
60 °C

実験手順

To a round bottom flask equipped with magnetic stirring and a nitrogen inlet was added methyl 3,4-dihydroxy-2-methylbenzoate (24.0 g, 132 mmol), (2R)-(−)-glycidyl tosylate (30.1 g, 132 mmol), potassium carbonate (21.8 g, 158 mmol), and DMF (264 mL). This mixture was heated to 60° C. for 5 hours. The mixture was cooled to room temperature, diluted with ether, and washed once with water. The aqueous wash was back extracted once with ether and the ethereal solutions combined. These organic solutions were then washed 3 times with saturated sodium chloride solution, dried over magnesium sulfate, filtered and evaporated to give a brown oil. This oil was chromatographed on silica gel eluting with 25% ether in hexanes to give a yellow oil, 3-hydroxymethyl-5 methyl-2,3-dihydrobenzo[1,4]dioxine-6-carboxylic acid methyl ester, (24.6 g, 103 mmol) in 78% yield. 1H-NMR (300 MHz, CD3COCD3) δ (ppm): 2.42 (s, 2H), 3.80 (s, 3H), 3.83 (m, 1H), 4.12 (dd, 1H), 4.23 (m, 2H), 4.42 (dd, 1H), 6.75 (d, 1H), 7.42 (d, 1H); TLC Rf=0.40 (1:1 ethyl acetate/hexane).

後処理

  1. customTo a round bottom flask equipped
  2. temperatureThe mixture was cooled to room temperature
  3. washwashed once with water
  4. washThe aqueous wash
  5. extractionwas back extracted once with ether
  6. washThese organic solutions were then washed 3 times with saturated sodium chloride solution
  7. dry with materialdried over magnesium sulfate
  8. filtrationfiltered
  9. customevaporated
  10. customto give a brown oil
  11. customThis oil was chromatographed on silica gel eluting with 25% ether in hexanes

出典と根拠

ORDレコード
ord-c43caef73d6b43caacb1bfe5481c0172
出典データセット
uspto-grants-2016_03
特許番号
US09272986B2

反応ノート

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