2-Cyano-6-methoxy benzothiazole → 2-Cyano-6-hydroxybenzothiazole

HRID 1855207Notes

Reaction equation

HRID 1855207 reaction equation
Cl.N1C=CC=CC=1.[C:8]([C:10]1[S:11][C:12]2[CH:18]=[C:17]([O:19]C)[CH:16]=[CH:15][C:13]=2[N:14]=1)#[N:9]>Cl>[C:8]([C:10]1[S:11][C:12]2[CH:18]=[C:17]([OH:19])[CH:16]=[CH:15][C:13]=2[N:14]=1)#[N:9]

Participants

4

Reactant 2

HCID 3421092-Cyano-6-methoxy benzothiazoleHCID 10176127Pyridinium chloride2×

Product 1

HCID 98819122-Cyano-6-hydroxybenzothiazoleYield 99%

Reagents, catalysts & solvents 1

HCID 313Hydrochloric AcidSolvent

Conditions

Temperature
200 °C

Procedure

Pyridine hydrochloride (2.32 g) was added to 2-cyano-6-methoxybenzothiazole 31 (51.4 mg, 0.271 mmol) and heated to 200° C. in an argon atmosphere to dissolve the pyridine hydrochloride, and the reaction mixture was stirred for 30 minutes. The reaction mixture was allowed to cool, and then 1 M hydrochloric acid (50 ml) was added. After extraction with ethyl acetate (3×50 ml) and drying of the organic layer with anhydrous sodium sulfate, the result was concentrated in vacuo. The resulting residue was purified by preparative thin-layer silica gel chromatography {one 20 cm×20 cm×1.75 mm plate; hexane-ethyl acetate (1:1)}, yielding 2-cyano-6-hydroxybenzothiazole 32 (47.2 mg, 99%) as a pale yellow solid.

Workup

  1. temperatureto cool
  2. extractionAfter extraction with ethyl acetate (3×50 ml)
  3. dry with materialdrying of the organic layer with anhydrous sodium sulfate
  4. concentrationthe result was concentrated in vacuo
  5. customThe resulting residue was purified by preparative thin-layer silica gel chromatography {one 20 cm×20 cm×1.75 mm plate

Sources & evidence

ORD record
ord-bfa6c06ce478447a912f102a6c55a1c3
Source dataset
uspto-grants-2015_02
Patent number
US08962854B2

Reaction notes

Loading…