Ammonium thiocyanate → 5-Bromo-6-methoxybenzo[d]thiazol-2-amine
Reaction equation
[Br:1][C:2]1[CH:3]=[C:4]([CH:6]=[CH:7][C:8]=1[O:9][CH3:10])[NH2:5].[S-:11][C:12]#[N:13].[NH4+].BrBr>CC(O)=O>[Br:1][C:2]1[C:8]([O:9][CH3:10])=[CH:7][C:6]2[S:11][C:12]([NH2:13])=[N:5][C:4]=2[CH:3]=1Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
To a solution of 3-bromo-4-methoxyaniline IV (2.0 g, 9.90 mmol) in AcOH (25.0 mL) was added ammonium thiocyanate (3.80 g, 49.50 mmol) and the reaction mixture was stirred at room temperature for 1 h. The reaction mixture was then cooled to 0° C. followed by addition of a solution of Br2 (0.60 mL, 11.0 mmol) in AcOH (10.0 mL). The reaction mixture was then allowed to stir at room temperature for 2 h. After the completion of the reaction (TLC monitoring), AcOH was distilled off, and the residue was cooled to 0° C. followed by basification with aqueous NH3 till pH 12 and extraction with EtOAc (2×250 mL). The combined organics was washed with brine, dried (Na2SO4), filtered and concentrated under reduced pressure to obtain the desired product (2.0 g, 78%). 1H NMR (400 MHz, DMSO-d6): δ 3.80 (s, 3H), 7.41 (br s, 2H), 7.49 (s, 1H) and 7.50 (s, 1H).
Workup
- temperatureThe reaction mixture was then cooled to 0° C.
- stirringto stir at room temperature for 2 h
- distillationwas distilled off
- temperaturethe residue was cooled to 0° C.
- extractionfollowed by basification with aqueous NH3 till pH 12 and extraction with EtOAc (2×250 mL)
- washThe combined organics was washed with brine
- dry with materialdried (Na2SO4)
- filtrationfiltered
- concentrationconcentrated under reduced pressure
Sources & evidence
- ORD record
- ord-002d8a4c893e4a648e93463b83ac84b2
- Source dataset
- uspto-grants-2012_10
- Patent number
- US08299065B2
Reaction notes
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