Protocatechuic Acid → 3,4-Dihydroxybenzohydrazide

HRID 1735512Notes

Reaction equation

HRID 1735512 reaction equation
[OH:1][C:2]1[CH:3]=[C:4]([CH:8]=[CH:9][C:10]=1[OH:11])[C:5](O)=[O:6].O.[NH2:13][NH2:14].ON1C=CC=CC1=O.C1(N=C=NC2CCCCC2)CCCCC1>O1CCCC1>[OH:1][C:2]1[CH:3]=[C:4]([CH:8]=[CH:9][C:10]=1[OH:11])[C:5]([NH:13][NH2:14])=[O:6]

Participants

6

Reactant 4

HCID 72Protocatechuic AcidHCID 10868DicyclohexylcarbodiimideHCID 24654Hydrazine hydrate (1:1)HCID 69975Hydroxypyridinone

Product 1

HCID 5863003,4-Dihydroxybenzohydrazide

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

16.9 g (0.11 mol) of 3,4-dihydroxybenzoic acid in 170 ml of tetrahydrofuran are treated with 5 g (0.1 mol) of hydrazine hydrate and 1.1 g (0.01 mol) of 1-hydroxy-2-(1H)-pyridone. A solution of 22.7 g (0.11 mol) of dicyclohexylcarbodiimide in 200 ml of tetrahydrofuran is added to the reaction mixture at 20° within 15 minutes. The reaction mixture is stirred at 20° for 16 hours. The resulting dicyclohexylurea is filtered off and the filtrate is evaporated. The residue is stirred with 60 ml of ethanol at 20° for 2 hours and the crystalline crude product is subsequently filtered off under suction and dried firstly in a water-jet vacuum and then in a high vacuum at 40°, whereby 3,4-dihydroxybenzoic acid hydrazide is obtained as a beige powder.

Workup

  1. filtrationThe resulting dicyclohexylurea is filtered off
  2. customthe filtrate is evaporated
  3. stirringThe residue is stirred with 60 ml of ethanol at 20° for 2 hours
  4. filtrationthe crystalline crude product is subsequently filtered off under suction
  5. dry with materialdried firstly in a water-jet vacuum

Sources & evidence

ORD record
ord-ee6a2ea0b572430cade832f4c933e61f
Source dataset
uspto-grants-1996_07
Patent number
US05536816

Reaction notes

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