Ammonium Hydroxide → 6-(Difluoromethoxy)-1,3-benzothiazol-2-amine

HRID 250013Notes

Reaction equation

HRID 250013 reaction equation
[F:1][CH:2]([F:11])[O:3][C:4]1[CH:10]=[CH:9][C:7]([NH2:8])=[CH:6][CH:5]=1.[S-:12][C:13]#[N:14].[K+].BrBr.[OH-].[NH4+]>C(O)(=O)C>[F:1][CH:2]([F:11])[O:3][C:4]1[CH:10]=[CH:9][C:7]2[N:8]=[C:13]([NH2:14])[S:12][C:6]=2[CH:5]=1

Participants

6

Reactant 4

HCID 14923Ammonium HydroxideHCID 24408BromineHCID 516872Potassium thiocyanate2×HCID 7373634-(Difluoromethoxy)aniline

Product 1

HCID 195858986-(Difluoromethoxy)-1,3-benzothiazol-2-amineYield 87.3%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent2×

Procedure

To 4-(difluoromethoxy)aniline (9.55 g, 60 mmol) in acetic acid (90 mL) was added potassium thiocyanate (KSCN) (12.41 mL, 240 mmol). The mixture was stirred for 20 minutes (KSCN dissolved into solution). To this mixture bromine (3.08 mL, 60.0 mmol) in acetic acid (40 mL) was added dropwise over 20 minutes. The reaction was stirred at room temperature overnight. It was poured into a mixture of 800 ml ice water and 200 ml saturated ammonium hydroxide. The product was extracted with ethyl acetate (5×). The organics were combined, washed with brine, dried over sodium sulfate, filtered and concentrated in vacuo to afford 6-(difluoromethoxy)benzo[d]thiazol-2-amine (12.6 g, 52.4 mmol, 87% yield) as a yellow solid.

Workup

  1. stirringThe reaction was stirred at room temperature overnight
  2. extractionThe product was extracted with ethyl acetate (5×)
  3. washwashed with brine
  4. dry with materialdried over sodium sulfate
  5. filtrationfiltered
  6. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-8c8c3eff73804232af6b26a08d8f76c1
Source dataset
uspto-grants-2011_01
Patent number
US07863291B2

Reaction notes

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