2,3-Dimethoxy-p-benzoquinone → Lonapalene

HRID 2107352Notes

Reaction equation

HRID 2107352 reaction equation
[CH3:1][O:2][C:3]1[C:4]([CH:6]=[CH:7][C:8](=[O:12])[C:9]=1[O:10][CH3:11])=[O:5].[Cl:13][C:14](=[CH2:19])[CH:15]=[CH:16]OC>C1C=CC=CC=1>[Cl:13][C:14]1[CH:19]=[C:6]2[C:7](=[CH:16][CH:15]=1)[C:8]([O:12][C:3](=[O:2])[CH3:9])=[C:9]([O:10][CH3:11])[C:3]([O:2][CH3:1])=[C:4]2[O:5][C:4](=[O:5])[CH3:6]

Participants

4

Reactant 2

HCID 765652,3-Dimethoxy-p-benzoquinoneHCID 542901063-Chloro-1-methoxybuta-1,3-diene

Product 1

HCID 56237LonapaleneYield 203.1%

Reagents, catalysts & solvents 1

HCID 241BenzeneSolvent

Procedure

A benzene (8 ml) solution of 2,3-dimethoxybenzo-1,4-quinone (1.0 g, 5.9 mmol) and 3-chloro-1-methoxy-1,3-butadiene (1.4 g, 12.0 mmol) is stirred for 30 hours under an inert atmosphere. After this time, the reaction mixture is concentrated and then dissolved in pyridine (8 ml). Acetic anhydride (3.0 g) is added, and the solution is stirred for 12 hours under an inert atmosphere. The contents are diluted ten-fold with water and extracted with ethyl acetate. The organics are then washed with water, brine, and then dried over sodium sulfate. Concentration, followed by flash chromatography (hexane/ethyl acetate 3:1) affords 2.03 g (93%) of a compound of the formula ##STR5##

Workup

  1. concentrationAfter this time, the reaction mixture is concentrated
  2. dissolutiondissolved in pyridine (8 ml)
  3. additionAcetic anhydride (3.0 g) is added
  4. additionThe contents are diluted ten-fold with water
  5. extractionextracted with ethyl acetate
  6. washThe organics are then washed with water, brine
  7. dry with materialdried over sodium sulfate
  8. concentrationConcentration

Sources & evidence

ORD record
ord-248cfa3ba8a0455b8a56b6ab461caaa2
Source dataset
uspto-grants-1990_06
Patent number
US04933489

Reaction notes

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