Methanol → TA 7552

HRID 974112Notes

Reaction equation

HRID 974112 reaction equation
C[O:2][CH:3](OC)[C:4]1[CH:9]=[C:8]([O:10][CH3:11])[C:7]([O:12][CH3:13])=[C:6]([O:14][CH3:15])[C:5]=1[CH:16](O)[C:17]1[CH:22]=[CH:21][C:20]([O:23][CH3:24])=[C:19]([O:25][CH3:26])[CH:18]=1.[C:30]([C:36]([O:38][CH3:39])=[O:37])#[C:31][C:32]([O:34][CH3:35])=[O:33].CO>C1(C)C=CC=CC=1.O.C1(C)C=CC(S(O)(=O)=O)=CC=1>[CH3:26][O:25][C:19]1[CH:18]=[C:17]([C:16]2[C:5]3[C:4](=[CH:9][C:8]([O:10][CH3:11])=[C:7]([O:12][CH3:13])[C:6]=3[O:14][CH3:15])[C:3]([OH:2])=[C:31]([C:32]([O:34][CH3:35])=[O:33])[C:30]=2[C:36]([O:38][CH3:39])=[O:37])[CH:22]=[CH:21][C:20]=1[O:23][CH3:24]

Participants

6

Reactant 3

HCID 887MethanolHCID 12980Dimethyl acetylenedicarboxylateHCID 105975732-(3,4-Dimethoxy-alpha-hydroxybenzyl)-3,4,5-trimethoxybenzaldehyde dimethyl acetal

Product 1

HCID 128664TA 7552Yield 68.1%

Reagents, catalysts & solvents 2

HCID 521998p-Toluenesulfonic acid monohydrateCatalystHCID 1140TolueneSolvent

Procedure

49.5 g of 2-(3,4-dimethoxy-α-hydroxybenzyl)-3,4,5-trimethoxybenzaldehyde dimethyl acetal are dissolved in 5 ml of toluene. 14.2 g of dimethyl acetylenedicarboxylate and 19 mg of p-toluenesulfonic acid monohydrate are added to the solution, and the mixture is refluxed for 3 hours. After cooling the reaction mixture, 200 ml of methanol are added thereto, and the mixture is allowed to stand at -30° C. overnight. The precipitated crystals are collected by filtration and recrystallized from ethyl acetate to give 33.1 g of 1-(3,4-dimethoxyphenyl)-2,3-bis(methoxycarbonyl)-4-hydroxy-6,7,8-trimethoxynaphthalene as colorless prisms.

Workup

  1. temperaturethe mixture is refluxed for 3 hours
  2. additionare added
  3. filtrationThe precipitated crystals are collected by filtration
  4. customrecrystallized from ethyl acetate

Sources & evidence

ORD record
ord-a096e08f74214632bda9283d6c597bc5
Source dataset
uspto-grants-1991_11
Patent number
US05066825

Reaction notes

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