ChemicalBook CAS DataBase List Ethyl 2-bromothiazole-4-carboxylate

Ethyl 2-bromothiazole-4-carboxylate synthesis

4synthesis methods

Product Name:Ethyl 2-bromothiazole-4-carboxylate
CAS Number:100367-77-9
Molecular formula:C6H6BrNO2S
Molecular Weight:236.09

Ethyl 2-amino-1,3-thiazole-4-carboxylate

5398-36-7

100367-77-9

Ethyl 2-aminothiazole-4-carboxylate (100 g, 581 mmol) and copper(II) bromide (195 g, 871 mmol) were dissolved in acetonitrile (1000 ml) at 0 °C. Subsequently, tert-butyl nitrite (104 ml, 871 mmol) was added slowly and dropwise. The reaction mixture was gradually warmed to room temperature and stirred continuously for 12 hours. After completion of the reaction, the reaction mixture was diluted with a mixture of ethyl acetate (1000 ml) and water (3000 ml) and the pH was adjusted to 2 with 1 N hydrochloric acid.The organic and aqueous layers were separated, and the aqueous layer was extracted three times with ethyl acetate (500 ml). All organic layers were combined, dried with anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by recrystallization from hexane to give pure ethyl 2-bromothiazole-4-carboxylate (115 g, 84% yield). The product was confirmed by 1H-NMR (400 MHz, DMSO-d6): δ 8.52 (s, 1H), 4.29 (q, J=7.1 Hz, 2H), 1.29 (t, J=7.1 Hz, 3H). Mass spectral analysis showed m/z 235.90 [M+1].

5398-36-7 Synthesis

5398-36-7
401 suppliers
$6.00/5g

100367-77-9
257 suppliers
$5.00/250mg

Yield:100367-77-9 84%

Reaction Conditions:

with 2-Methyl-2-nitropropane;copper(ll) bromide in acetonitrile at 0 - 20; for 12 h;

Steps:

1.A Step A: Preparation of ethyl 2-bromo-1,3-thiazole-4-carboxylate
To a solution of ethyl 2-aminothiazole-4-carboxylate (100 g, 581 mmol) and copper (II) bromide (195 g,871 mmol) in acetonitrile (1000 ml) at 0 °C, tert-butylnitrite (104 ml, 871 mmol) was added dropwise. The reaction mixture was warmed to room temperature and stirred for 12h. After completion of thereaction, the reaction mixture was diluted with a mixture of ethyl acetate (1000 ml) and water (3000 ml) and then acidified to pH 2 using iN hydrochloric acid. The two layers were separated and the aqueous layer was again extracted three times with ethyl acetate (500 ml). The combined organic layers were dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by recrystallization from hexane to obtain pure ethyl 2-bromo-1,3-thiazole-4-carboxylate (115 g,84% yield).‘H-NMR (400 MHz, DMSO-d6) 8.52 (s, IH), 4.29 (q, J 7.1 Hz, 2H), 1.29 (t,J 7.1 Hz, 3H)MS: m/z235.90. [M+1].

References:

PI INDUSTRIES LTD.;SHANBHAG, Gajanan;DODDA, Ranga Prasad;KAMBLE, Ganesh Tatya;KALE, Yuvraj Navanath;RENUGADEVI, G.;MANJUNATHA, Sulur G;S.P., Mohan Kumar;AUTKAR, Santosh Shridhar;GARG, Ruchi;VENKATESHA, Hagalavadi M;MAVINAHALLI, Jagadeesh Nanjegowda;KLAUSENER, Alexander G.M. WO2018/193387, 2018, A1 Location in patent:Page/Page column 92

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