Hydrochloric Acid → 4,6-Diaminoresorcinol Dihydrochloride

HRID 488892

Reaction equation

HRID 488892 reaction equation
[N+:1]([C:4]1[CH:10]=[C:9]([N+:11]([O-])=O)[C:7]([OH:8])=[CH:6][C:5]=1[OH:14])([O-])=O.CO.CC1C2COC(=O)C=2C(O[C@@H]2O[C@H](C(O)=O)[C@@H](O)[C@H](O)[C@H]2O)=C(C/C=C(/CCC(O)=O)\C)C=1OC.[ClH:52]>O.[C].[Pd]>[ClH:52].[ClH:52].[NH2:1][C:4]1[CH:10]=[C:9]([NH2:11])[C:7]([OH:8])=[CH:6][C:5]=1[OH:14]

Participants

7

Reactant 4

HCID 313Hydrochloric AcidHCID 887MethanolHCID 611584,6-DinitroresorcinolHCID 6442661Mycophenolic acid glucuronide

Product 1

HCID 27336484,6-Diaminoresorcinol DihydrochlorideYield 46.4%

Reagents, catalysts & solvents 2

HCID 178418390HCID 178418390, compoundCatalystHCID 962WaterSolvent

Procedure

30 g of crude 4,6-dinitroresorcin were recrystallized in 1,500 g of ethanol to obtain 24.1 g of purified 4,6-dinitroresorcin. Next, 4.0 g of this purified 4,6-dinitroresorcin were added to methanol, and 0.0396 g of 5% palladium carbon (a 50% wet product) was then added thereto, followed by hydrogenation at 60° C. under an average hydrogen pressure of 0.8 MPaG. The reaction mass was poured into a 5% aqueous hydrochloric acid solution containing 6,000 ppm of stannous chloride, and then filtered to remove the catalyst. Afterward, analysis was carried out by HPLC, and it was confirmed that desired 4,6-diaminoresorcin was produced in a yield of 96.2 mol %. The solvent was removed from the filtrate by an evaporator to obtain the crystals of crude 4,6-dinitroresorcin. The crystals were dissolved in 21.3 g of water containing 0.32 g of stannous chloride, and 0.2 g of activated carbon was added to the solution. Thereafter, the solution was stirred for 30 minutes and then filtered to remove the activated carbon. When 16.0 g of 36% hydrochloric acid were gradually added dropwise to the filtrate, the gradual deposition of crystals was observed. The crystals were collected by filtration and then dried at 50° C. under reduced pressure to obtain 3.03 g (yield=46.4%) of 4,6-diaminoresorcin dihydrochloride.

Workup

  1. additionwas then added
  2. customfollowed by hydrogenation at 60° C. under an average hydrogen
  3. filtrationfiltered
  4. customto remove the catalyst
  5. customwas produced in a yield of 96.2 mol %
  6. customThe solvent was removed from the filtrate by an evaporator
  7. customto obtain the crystals of crude 4,6-dinitroresorcin
  8. additionwas added to the solution
  9. filtrationfiltered
  10. customto remove the activated carbon
  11. additionWhen 16.0 g of 36% hydrochloric acid were gradually added dropwise to the filtrate
  12. filtrationThe crystals were collected by filtration
  13. customdried at 50° C. under reduced pressure

Sources & evidence

ORD record
ord-b906e51402764bcd9e6827cb433d7bad
Source dataset
uspto-grants-2005_12
Patent number
US06974881B2

Linked notes

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