Sulfuric Acid → 1-(Ethoxycarbonyl)-4-(4-fluoroanilino)piperidine-4-carboximidic acid

HRID 1065257Notes

Reaction equation

HRID 1065257 reaction equation
[C:1]([C:3]1([NH:14][C:15]2[CH:20]=[CH:19][C:18]([F:21])=[CH:17][CH:16]=2)[CH2:8][CH2:7][N:6]([C:9]([O:11][CH2:12][CH3:13])=[O:10])[CH2:5][CH2:4]1)#[N:2].S(=O)(=O)(O)[OH:23].[OH-].[Na+]>O>[C:1]([C:3]1([NH:14][C:15]2[CH:16]=[CH:17][C:18]([F:21])=[CH:19][CH:20]=2)[CH2:8][CH2:7][N:6]([C:9]([O:11][CH2:12][CH3:13])=[O:10])[CH2:5][CH2:4]1)(=[O:23])[NH2:2]

Participants

5

Reactant 3

HCID 1118Sulfuric AcidHCID 14798Sodium HydroxideHCID 3018977Ethyl 4-cyano-4-(4-fluoroanilino)piperidine-1-carboxylate

Product 1

HCID 30189781-(Ethoxycarbonyl)-4-(4-fluoroanilino)piperidine-4-carboximidic acid

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

127.5 parts of ethyl 4-cyano-4-(4-fluorophenylamino)-1-piperidinecarboxylate are added dropwise to 360 parts of concentrated sulfuric acid (exothermic reaction: temperature rises to 50° C.). Upon completion, the whole is stirred overnight at room temperature. The reaction mixture is poured onto crushed ice and 250 parts of water are added. The whole is alkalized with sodium hydroxide solution at a temperature of 40°-50° C., whereupon the product is precipitated. It is filtered off, washed with water and taken up in boiling trichloromethane. The latter is washed twice with water, dried and evaporated, yielding 82.1 parts of less pure ethyl 4-carbamoyl-4-(4-fluorophenylamino)-1-piperidinecarboxylate.

Workup

  1. additionThe reaction mixture is poured
  2. additionare added
  3. customis precipitated
  4. filtrationIt is filtered off
  5. washwashed with water
  6. washThe latter is washed twice with water
  7. customdried
  8. customevaporated

Sources & evidence

ORD record
ord-9b84ed9d46ed4223860024fc302dbe56
Source dataset
uspto-grants-1982_05
Patent number
US04329353

Reaction notes

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