Ammonia → 5-(Benzothiazol-2-yl)-2-methyl-1-(tetrahydropyran-4-yl)benzimidazole

HRID 74160

Reaction equation

HRID 74160 reaction equation
Cl.[CH3:2][C:3]1[N:7]([CH:8]2[CH2:13][CH2:12][O:11][CH2:10][CH2:9]2)[C:6]2[CH:14]=[CH:15][C:16]([C:18](O)=O)=[CH:17][C:5]=2[N:4]=1.[NH2:21][C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][C:23]=1[SH:28].N>>[S:28]1[C:23]2[CH:24]=[CH:25][CH:26]=[CH:27][C:22]=2[N:21]=[C:18]1[C:16]1[CH:15]=[CH:14][C:6]2[N:7]([CH:8]3[CH2:13][CH2:12][O:11][CH2:10][CH2:9]3)[C:3]([CH3:2])=[N:4][C:5]=2[CH:17]=1

Participants

4

Reactant 3

HCID 222AmmoniaHCID 87132-AminothiophenolHCID 674984452-methyl-1-(tetrahydropyran-4-yl)benzimidazole-5-carboxylic acid HCl salt

Product 1

HCID 498213795-(Benzothiazol-2-yl)-2-methyl-1-(tetrahydropyran-4-yl)benzimidazoleYield 1.9%

Conditions

Temperature
150 °C

Procedure

A 4-neck flask (50 mL) equipped with reflux condenser was charged with 2-methyl-1-(tetrahydropyran-4-yl)benzimidazole-5-carboxylic acid HCl salt (see Working Example 4-3) (0.28 g, 1.08 mmol), 2-aminobenzenethiol (0.14 g, 1.08 mmol) and polyphosphoric acid (approx. 11 g), and this was heated to 150° C. and stirred for 17 hours. After being allowed to cool to room temperature, this was cooled in ice (0 to 5° C.), and concentrated aqueous ammonia (28%) was added to the liquid to give approx. pH 9. After distilling off the solvent under reduced pressure, the brown viscous residue was extracted with ethyl acetate, this was dried over anhydrous magnesium sulfate. The residue obtained after again distilling off the solvent under reduced pressure was purified by PTLC to yield the title compound (0.007 g, 1.8% yield) as greenish-pale yellow crystals.

Workup

  1. customA 4-neck flask (50 mL) equipped
  2. temperaturewith reflux condenser
  3. temperatureto cool to room temperature
  4. temperaturethis was cooled in ice (0 to 5° C.)
  5. customto give approx. pH 9
  6. distillationAfter distilling off the solvent under reduced pressure
  7. extractionthe brown viscous residue was extracted with ethyl acetate
  8. dry with materialthis was dried over anhydrous magnesium sulfate
  9. customThe residue obtained
  10. distillationafter again distilling off the solvent under reduced pressure
  11. customwas purified by PTLC

Sources & evidence

ORD record
ord-2a6d9b5436cc47f0a047a04680d0c6ab
Source dataset
uspto-grants-2014_09
Patent number
US08829035B2

Linked notes

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