Piperazine → 5-Fluoro-2-(piperazin-1-ylmethyl)-1,3-benzothiazole

HRID 1772287Notes

Reaction equation

HRID 1772287 reaction equation
Br[CH2:2][C:3]1[S:4][C:5]2[CH:11]=[CH:10][C:9]([F:12])=[CH:8][C:6]=2[N:7]=1.C(=O)([O-])[O-].[K+].[K+].[NH:19]1[CH2:24][CH2:23][NH:22][CH2:21][CH2:20]1>C(#N)C>[F:12][C:9]1[CH:10]=[CH:11][C:5]2[S:4][C:3]([CH2:2][N:19]3[CH2:24][CH2:23][NH:22][CH2:21][CH2:20]3)=[N:7][C:6]=2[CH:8]=1

Participants

5

Reactant 3

HCID 4837PiperazineHCID 11430Potassium CarbonateHCID 144586272-(Bromomethyl)-5-fluorobenzo[d]thiazole

Product 1

HCID 623094565-Fluoro-2-(piperazin-1-ylmethyl)-1,3-benzothiazole

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Procedure

A mixture of 2-(bromomethyl)-5-fluoro-1,3-benzothiazole (150 mg, 0.61 mmol), potassium carbonate (253 mg, 1.83 mmol) and piperazine (263 mg, 3.05 mmol) in acetonitrile (30 ml) was heated at reflux for 4.5 hours with stirring and was then concentrated under vacuum. The residue was dissolved in dichloromethane (100 ml), washed with brine (3×50 mL), dried over anhydrous sodium sulfate, filtered and concentrated under vacuum to afford 5-fluoro-2-(piperazin-1-ylmethyl)-1,3-benzothiazole as a yellow crude solid (130 mg). (ES, m/z): [M+H]+ 252.1; 1H NMR (400 MHz, CDCl3): δ 7.81 (dd, J=8.8, 5.2 Hz, 1H), 7.70 (dd, J=9.6, 2.4 Hz, 1H), 7.16-7.11 (m, 1H), 3.93 (s, 2H), 2.97-2.93 (m, 4H), 2.64-2.63 (m, 4H), 1.98 (s, 1H).

Workup

  1. temperaturewas heated
  2. temperatureat reflux for 4.5 hours
  3. concentrationwas then concentrated under vacuum
  4. dissolutionThe residue was dissolved in dichloromethane (100 ml)
  5. washwashed with brine (3×50 mL)
  6. dry with materialdried over anhydrous sodium sulfate
  7. filtrationfiltered
  8. concentrationconcentrated under vacuum

Sources & evidence

ORD record
ord-33fde6eaea2f40ffa1dfe43f64403f41
Source dataset
uspto-grants-2016_02
Patent number
US09249102B2

Reaction notes

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