Urea → 4-Chloro-3-nitrobenzamide

HRID 1079094

Reaction equation

HRID 1079094 reaction equation
[Cl:1][C:2]1[CH:10]=[CH:9][C:5]([C:6](O)=[O:7])=[CH:4][C:3]=1[N+:11]([O-:13])=[O:12].[NH2:14]C(N)=O>ClC1C=CC=CC=1Cl.P(O)(O)O>[Cl:1][C:2]1[CH:10]=[CH:9][C:5]([C:6]([NH2:14])=[O:7])=[CH:4][C:3]=1[N+:11]([O-:13])=[O:12]

Participants

5

Reactant 2

HCID 1176UreaHCID 73204-Chloro-3-nitrobenzoic acid

Product 1

HCID 279424-Chloro-3-nitrobenzamideYield 90.2%

Reagents, catalysts & solvents 2

HCID 107909Phosphorous acidCatalystHCID 72391,2-DichlorobenzeneSolvent

Conditions

Temperature
25 °C

Procedure

100 g (0.5 mol) of 4-chloro-3-nitrobenzoic acid, 36 g (0.6 mol) of urea and 0.5 g of phosphorous acid are heated in 250 ml of 1,2-dichlorobenzene with stirring at from 165° to 178° C. for 8 h. After cooling to 25° C. the solid is filtered off with suction and washed with 50 ml of 1,2-dichlorobenzene. The filter cake is introduced into 250 ml of water, and the mixture is adjusted to a pH of 12 using aqueous sodium hydroxide solution and subjected to steam distillation. Subsequently the solid is filtered off with suction and dried at 100° C. 89.7 g of 4-chloro-3-nitrobenzamide are obtained having a melting point of from 146° to 149° C. This corresponds to a yield of 90.2% of theory. By acidification of the aqueous mother liquor to pH 2, 4.9 g of 4-chloro-3-nitrobenzoic acid (4.9% of theory) are obtained, which can be employed again in a subsequent batch.

Workup

  1. filtrationis filtered off with suction
  2. washwashed with 50 ml of 1,2-dichlorobenzene
  3. additionThe filter cake is introduced into 250 ml of water
  4. distillationsubjected to steam distillation
  5. filtrationSubsequently the solid is filtered off with suction
  6. customdried at 100° C

Sources & evidence

ORD record
ord-33c7fca5dc594b0988085ffe4f439050
Source dataset
uspto-grants-1996_08
Patent number
US05550286

Linked notes

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