Phosphorus sulfide (P2S5) → Ethyl 5-phenylthiazole-2-carboxylate
Reaction equation
P12(SP3(SP(SP(S3)(S1)=S)(=S)S2)=S)=[S:2].O=[C:16]([NH:22][CH2:23][C:24](=O)[C:25]1[CH:30]=[CH:29][CH:28]=[CH:27][CH:26]=1)[C:17]([O:19][CH2:20][CH3:21])=[O:18]>C(Cl)(Cl)Cl>[C:25]1([C:24]2[S:2][C:16]([C:17]([O:19][CH2:20][CH3:21])=[O:18])=[N:22][CH:23]=2)[CH:30]=[CH:29][CH:28]=[CH:27][CH:26]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
P2S5 (25.5 g, 114.7 mmol) was added to a solution of ethyl 2-oxo-2-((2-oxo-2-phenylethyl)amino)acetate (13.5 g, 57.39 mmol) in dry CHCl3 (150 mL), and the resulting reaction mixture was heated to reflux for 5 h. The reaction mixture was quenched with water and the organic product was extracted with CHCl3. The combined extracts were washed with H2O and brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The crude product was purified by column chromatography (silica gel 60-120 mesh, eluent 10-15% EtOAc in petroleum ether) to afford ethyl 5-phenylthiazole-2-carboxylate (10 g, yield 75%) as a white solid. 1H NMR (400 MHz, CDCl3) δ 8.16 (s, 1H), 7.64-7.62 (m, 2H), 7.48-7.39 (m, 3H), 4.53-4.47 (q, J=7.0 Hz, 2H), 1.49-1.45 (t, J=7.2 Hz, 3H). MS (ESI) m/z: Calculated for C12H11NO2S: 233.05. found: 234.0 (M+H)+.