Reaktion #1269857

Reaktionsgleichung

2-phenyl-1,3-thiazole-4-carboxylic acid

THF

n-BuLi

Br2

→

desired product

5-Bromo-2-phenyl-thiazole-4-carboxylic acid

Lösungsmittel

cyclohexane

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added over 10 min
2. 2
   TemperaturThe reaction mixture was then cooled to 0° C.
3. 3
   Sonstigecarefully quenched with HCl (1M, 32 mL)
4. 4
   Extraktionextracted with EtOAc (2×)
5. 5
   Waschenphases were washed with aq. sodium thiosulfate (20%)
6. 6
   Trocknendried over MgSO4
7. 7
   Sonstigeevaporated to dryness

Vorschrift

To a solution of 2-phenyl-1,3-thiazole-4-carboxylic acid (3.2 g) in abs. THF (190 mL) was added at 78° C. over 10 min n-BuLi (25 mL, 1.6M in hexanes). After addition, Br2 (1.3 mL) in cyclohexane (7.4 mL) was added over 10 min. The reaction mixture was allowed to warm up to RT and was stirred at this temperature for 3 h. The reaction mixture was then cooled to 0° C., carefully quenched with HCl (1M, 32 mL) and extracted with EtOAc (2×). The combined org. phases were washed with aq. sodium thiosulfate (20%), dried over MgSO4 and evaporated to dryness to give 4.5 g of the desired product. The crude was used without further purification.

Quelle