Sulfuric Acid → 2,6-Dichloro-5-fluoronicotinamide

HRID 1599018Notes

Reaction equation

HRID 1599018 reaction equation
[Cl:1][C:2]1[C:7]([C:8]#[N:9])=[CH:6][C:5]([F:10])=[C:4]([Cl:11])[N:3]=1.C(C1C=CC=CN=1)#N.S(=O)(=O)(O)[OH:21]>>[Cl:1][C:2]1[N:3]=[C:4]([Cl:11])[C:5]([F:10])=[CH:6][C:7]=1[C:8]([NH2:9])=[O:21]

Participants

4

Reactant 3

HCID 1118Sulfuric AcidHCID 7522Pyridine-2-carbonitrileHCID 27338492,6-Dichloro-5-fluoro-3-pyridinecarbonitrile

Product 1

HCID 27740222,6-Dichloro-5-fluoronicotinamide

Conditions

Temperature
10 °C

Procedure

The amide was prepared from the 2,6-dichloro-5-fluoro-3-cyanopyridine described in Example 1b. The cyanopyridine was placed in 12 L flask, cooled to 5°-10° C. in an ice bath, and 2300 mL of concentrated sulfuric acid was added. The residual DCE was then removed under vacuum at room temperature. After removal of the DCE the mixture was heated at 65°-70° C. for 1-2 hours and monitored by HPLC. After about 2 hours the mixture was cooled to about 10° C. in an ice bath. The amide product (3) formed was used directly for the next step without isolation or purification.

Workup

  1. temperaturecooled to 5°-10° C. in an ice bath
  2. customThe residual DCE was then removed under vacuum at room temperature
  3. customAfter removal of the DCE the mixture
  4. temperaturewas heated at 65°-70° C. for 1-2 hours

Sources & evidence

ORD record
ord-b77611ef85184b64a2f2ea82700e71c5
Source dataset
uspto-grants-1998_04
Patent number
US05739342

Reaction notes

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