Hydrogen Bromide → 2-Amino-6-benzothiazolol

HRID 1867952Notes

Reaction equation

HRID 1867952 reaction equation
[NH2:1][C:2]1[S:3][C:4]2[CH:10]=[C:9]([O:11]CC)[CH:8]=[CH:7][C:5]=2[N:6]=1.Br.O>C(O)(=O)C>[NH2:1][C:2]1[S:3][C:4]2[CH:10]=[C:9]([OH:11])[CH:8]=[CH:7][C:5]=2[N:6]=1

Participants

5

Reactant 3

HCID 260Hydrogen BromideHCID 962WaterHCID 7192Amino-6-ethoxybenzothiazole, 2-

Product 1

HCID 334622-Amino-6-benzothiazololYield 79.5%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent

Conditions

Temperature
150 °C

Procedure

A solution of 2-amino-6-ethoxybenzothiazole (5 g, 25.74 mmol) and of 48% hydrobromic acid in water (130 ml, 1.141 mol) in 65 ml of acetic acid is distributed in ten 20 ml microwave tubes, and then heated at 150° C. by microwave for 200 seconds. The reaction medium is concentrated. The residue is taken up in 200 ml of water, basified to pH 8 by addition of 75 ml of saturated NaHCO3 solution and extracted with ethyl acetate, washed with saturated sodium chloride solution, dried over magnesium sulfate and concentrated to dryness to give 3.4 g of 2-aminobenzothiazol-6-ol (gray powder).

Workup

  1. concentrationThe reaction medium is concentrated
  2. additionbasified to pH 8 by addition of 75 ml of saturated NaHCO3 solution
  3. extractionextracted with ethyl acetate
  4. washwashed with saturated sodium chloride solution
  5. dry with materialdried over magnesium sulfate
  6. concentrationconcentrated to dryness

Sources & evidence

ORD record
ord-867fa89e4b194fb8b991cf2279812ef9
Source dataset
uspto-grants-2009_12
Patent number
US07632952B2

Reaction notes

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