Ethyl 2,3-dihydrobenzo[b][1,4]dioxine-6-carboxylate → 2,3-Dihydro-1,4-benzodioxin-6-methanol

HRID 17936Notes

Reaction equation

HRID 17936 reaction equation
[H-].[H-].[H-].[H-].[Li+].[Al+3].C([O:9][C:10]([C:12]1[CH:21]=[CH:20][C:15]2[O:16][CH2:17][CH2:18][O:19][C:14]=2[CH:13]=1)=O)C>C1COCC1>[O:16]1[C:15]2[CH:20]=[CH:21][C:12]([CH2:10][OH:9])=[CH:13][C:14]=2[O:19][CH2:18][CH2:17]1

Participants

4

Reactant 2

HCID 16648286Ethyl 2,3-dihydrobenzo[b][1,4]dioxine-6-carboxylateHCID 21226445Aluminium lithium hydride

Product 1

HCID 27761742,3-Dihydro-1,4-benzodioxin-6-methanolYield 88.6%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

To a suspension of LAH (2.8 g, 74 mmol) in THF (20 mL) was added dropwise a solution of 2,3-dihydro-benzo[1,4]dioxine-6-carboxylic acid ethyl ester (15 g, 72 mmol) in THF (10 mL) at 0° C. under N2. The mixture was stirred at room temperature for 1 h and then quenched carefully with addition of water (2.8 mL) and NaOH (10%, 28 mL) with cooling. The precipitated solid was filtered off and the filtrate was evaporated to dryness to obtain (2,3-dihydro-benzo[1,4]dioxin-6-yl)-methanol (10.6 g). 1H NMR (300 MHz, DMSO-d6) δ 6.73-6.78 (m, 3H), 5.02 (t, J=5.7 Hz, 1H), 4.34 (d, J=6.0 Hz, 2H), 4.17-4.20 (m, 4H).

Workup

  1. customquenched carefully with addition of water (2.8 mL) and NaOH (10%, 28 mL)
  2. temperaturewith cooling
  3. filtrationThe precipitated solid was filtered off
  4. customthe filtrate was evaporated to dryness

Sources & evidence

ORD record
ord-7042c1bba410490598bf68449302d45d
Source dataset
uspto-grants-2010_06
Patent number
US07741321B2

Reaction notes

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