ChemicalBook CAS DataBase List 4-Methylthiazole

4-Methylthiazole synthesis

9synthesis methods

Product Name:4-Methylthiazole
CAS Number:693-95-8
Molecular formula:C4H5NS
Molecular Weight:99.15

1603-91-4 Synthesis

1603-91-4
285 suppliers
$5.00/1g

693-95-8
337 suppliers
$6.00/5g

Yield:693-95-8 72%

Reaction Conditions:

Stage #1:4-methylthiazol-2-ylamine with sulfuric acid;sodium nitrite in water at -15 - -10; for 4 h;
Stage #2: with sodium hypophosphite in water at -10 - -5; for 6 h;Temperature;

Steps:

3.3.3 3.3) Synthesis of 4-Methylthiazole
Take 68.4g (0.6mol) 2-amino-4-methylthiazole in a 2L three-necked flask, then add a mixture of 150mL water and 90mL concentrated sulfuric acid,The reaction mixture was cooled to -10 to -15°C, and an aqueous solution of sodium nitrite (45.5 g, 0.66 mol of sodium nitrite dissolved in 160 mL of water) was added dropwise at this temperature within 2.5 hours.After the addition is completed, the temperature is maintained for 1.5 hours, at which time the diazonium salt is obtained.Then, an aqueous solution of sodium hypophosphite (76.3 g, 0.72 mol) sodium hypophosphite was dissolved in 320 mL of water dropwise at -5 to -10°C.After the addition was complete, stirring was continued at this temperature for 6 h. Afterwards, the pH was adjusted to 9-10 with a 45% sodium hydroxide solution.Then it was extracted three times with 110 mL of dichloromethane, and the organic phases were combined and dried over anhydrous sodium sulfate.Distillation first distills off CH3Cl2 at low temperature of 30-40°C, and then raises the temperature to collect fractions at 133-135°C to obtain 43.2 g of a yellow liquid with a yield of 72%.

References:

Yantai Beisen Pharmaceutical Technology Co., Ltd.;Bi Haidong;Zhi Caixia;Zhang Yixing CN104557902, 2018, B Location in patent:Paragraph 0061; 0081; 0086; 0087

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20485-41-0 Synthesis