Methanol → p-Toluenesulfonic acid

HRID 259719Notes

Reaction equation

HRID 259719 reaction equation
[C:1]([NH:4][C:5]1[CH:6]=[C:7]([C:18]([O:20][CH3:21])=[O:19])[C:8](=[CH:13][C:14]=1[N+:15]([O-])=O)[C:9]([O:11][CH3:12])=[O:10])(=O)[CH3:2].CO.[C:24]1([CH3:34])[CH:29]=[CH:28][C:27]([S:30]([OH:33])(=[O:32])=[O:31])=[CH:26][CH:25]=1>[Pt].C1(C)C=CC=CC=1>[CH3:34][C:24]1[CH:29]=[CH:28][C:27]([S:30]([OH:33])(=[O:32])=[O:31])=[CH:26][CH:25]=1.[CH3:2][C:1]1[NH:15][C:14]2[CH:13]=[C:8]([C:9]([O:11][CH3:12])=[O:10])[C:7]([C:18]([O:20][CH3:21])=[O:19])=[CH:6][C:5]=2[N:4]=1

Participants

7

Reactant 3

HCID 887MethanolHCID 6101p-Toluenesulfonic acidHCID 14574474Dimethyl 4-acetamido-5-nitrophthalate

Product 2

HCID 6101p-Toluenesulfonic acidHCID 21827571HCID 21827571, compound

Reagents, catalysts & solvents 2

HCID 23939PlatinumCatalystHCID 1140TolueneSolvent

Procedure

A mixture of dimethyl 4-acetamido-5-nitrophthalate, methanol and 5% platinum on carbon is hydrogenated in a Parr hydrogenator. The reaction mixture is filtered through diatomaceous earth and the filtrate is concentrated in vacuo. The thus-obtained crude diamine intermediate (48.09, 0.180 mol) is mixed with p-toluenesulfonic acid (51.4 g, 0.270 mol) and toluene (400 mL), and stirred for 2 hours at reflux temperatures with azeotropic removal of water, cooled and concentrated in vacuo. The resultant residue is recrystallized from methanol to afford the p-toluene sulfonate salt of the title product. The salt is dissolved in hot water, made basic with sodium bicarbonate and extracted with methylene chloride. The combined extracts are washed with brine, dried (MgSO4) and concentrated in vacuo to give a red solid. Recrystallization of a portion of the red solid affords the title product as white crystals, mp 151°-152° C.

Workup

  1. filtrationThe reaction mixture is filtered through diatomaceous earth
  2. concentrationthe filtrate is concentrated in vacuo
  3. customThe thus-obtained crude diamine intermediate (48.09, 0.180 mol)
  4. temperatureat reflux temperatures
  5. customwith azeotropic removal of water
  6. temperaturecooled
  7. concentrationconcentrated in vacuo
  8. customThe resultant residue is recrystallized from methanol

Sources & evidence

ORD record
ord-03bc7dc89f474844b6f732b87341517e
Source dataset
uspto-grants-1996_06
Patent number
US05523279

Reaction notes

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