Benzothiazole, 4-methoxy-2-methyl- (7CI,8CI,9CI) synthesis

5synthesis methods

Product Name:Benzothiazole, 4-methoxy-2-methyl- (7CI,8CI,9CI)
CAS Number:5304-19-8
Molecular formula:C9H9NOS
Molecular Weight:179.24

29277-46-1 Synthesis

29277-46-1
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Benzothiazole, 4-methoxy-2-methyl- (7CI,8CI,9CI)

5304-19-8
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Yield:5304-19-8 25%

Reaction Conditions:

with potassium hydroxide;potassium hexacyanoferrate(III) in water at 100; for 4 h;

Steps:

156.2 Step 2
4-Methoxy-2-methylbenzo[d]thiazole (Compound 156-2)

Compound 156-1 (8.0 g, 44.19 mmol) was dissolved in water (480 mL).
Potassium hydroxide (11.38 g, 203.27 mmol) and potassium ferricyanide (33.40 g, 101.65 mmol) were added to the solution, and the mixture was stirred at 100°C for 4 hours.
The mixture was left to cool to room temperature and water was added to the mixture.
The organic layer was extracted with ethyl acetate, dried over anhydrous sodium sulfate, and concentrated under reduced pressure.
The residue was purified by silica gel column chromatography (hexane/ethyl acetate = 100/0 -> 80/20) to obtain compound 156-2 (2.0 g, 25%).
¹H NMR (400 MHz, CDCl₃, δ): 7.40 (dd, J = 8.0, 0.8 Hz, 1H), 7.29 (t, J = 8.0 Hz, 1H), 6.88 (dd, J = 8.0, 0.4 Hz, 1H), 4.03 (s, 3H), 2.84 (s, 3H).

References:

EP3712129,2020,A1 Location in patent:Paragraph 1231