Water → 2-(3,4-dihydro-2H-1-benzopyran-3-yl)ethan-1-ol

HRID 1032392Notes

Reaction equation

HRID 1032392 reaction equation
C[O:2][C:3]([CH2:5][CH:6]1[CH2:15][C:14]2[C:9](=[CH:10][CH:11]=[CH:12][CH:13]=2)[O:8][CH2:7]1)=O.[H-].[Al+3].[Li+].[H-].[H-].[H-].O.[OH-].[Na+]>O1CCCC1.C(OCC)C>[OH:2][CH2:3][CH2:5][CH:6]1[CH2:15][C:14]2[C:9](=[CH:10][CH:11]=[CH:12][CH:13]=2)[O:8][CH2:7]1

Participants

7

Reactant 4

HCID 962Water2×HCID 14798Sodium HydroxideHCID 148384133-MethoxycarbonylmethylchromanHCID 21226445Aluminium lithium hydride

Product 1

HCID 148384142-(3,4-dihydro-2H-1-benzopyran-3-yl)ethan-1-olYield 100%

Reagents, catalysts & solvents 2

HCID 3283Diethyl EtherSolventHCID 8028TetrahydrofuranSolvent

Procedure

At room temperature and while stirring, a solution of 7.22 g (35 mmol) of 3-methoxycarbonylmethylchroman in 50 ml of absolute tetrahydrofuran is added dropwise within a period of 30 minutes to a suspension of 1.33 g (35 mmol) of lithium aluminium hydride in 50 ml of absolute diethyl ether. Stirring is continued at room temperature for a further 16 hours and then the whole is carefully decomposed with 1.33 ml of water, 1.33 ml of sodium hydroxide solution (15% strength) and 4.0 ml of water. The precipitate formed is filtered off with suction and the filtrate is concentrated by evaporation in vacuo. The oily residue is dissolved in diethyl ether. The solution is washed with water, dried over sodium sulphate and concentrated by evaporation in vacuo. 6.23 g (100%) of 3-(2-hydroxyethyl)chroman are obtained in the form of a yellow oil.

Workup

  1. stirringStirring
  2. customThe precipitate formed
  3. filtrationis filtered off with suction
  4. concentrationthe filtrate is concentrated by evaporation in vacuo
  5. dissolutionThe oily residue is dissolved in diethyl ether
  6. washThe solution is washed with water
  7. dry with materialdried over sodium sulphate
  8. concentrationconcentrated by evaporation in vacuo

Sources & evidence

ORD record
ord-b9f26cf967564b42a3cdc812ac484dbe
Source dataset
uspto-grants-1990_09
Patent number
US04957928

Reaction notes

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