Cl[C:2]1[S:3][CH:4]=[CH:5][N:6]=1.[C:7]([O:11][C:12]([CH3:15])([CH3:14])[CH3:13])(=[O:10])[CH2:8][CH3:9].[CH3:16][Si]([N-][Si](C)(C)C)(C)C.[Na+].CI>C1(C)C=CC=CC=1>[CH3:9][C:8]([C:2]1[S:3][CH:4]=[CH:5][N:6]=1)([CH3:16])[C:7]([O:11][C:12]([CH3:15])([CH3:14])[CH3:13])=[O:10]Toluene (30 mL) was placed in a nitrogen-flushed flask and degassed with nitrogen (20 min). 2-Chlorothiazole (900 mg, 7.53 mmol) and tert-butyl propionate (1.176 g, 9.03 mmol) were added, and the mixture was cooled to 0° C. NaHMDS (0.6 M in toluene, 30.1 mL, 18.06 mmol) was added. The reaction was stirred for 2 h at 0° C., allowed to warm to room temperature, and stirred for 18 h at room temperature. Methyl iodide (3.85 g, 27.1 mmol) was then added. After 1 h at room temperature, the orange reaction was quenched (under nitrogen) with aqueous saturated NH4Cl. The mixture was extracted with ethyl acetate (2×), and the combined organic layers were washed with brine, dried (Na2SO4), filtered and evaporated. Flash chromatography (0-25% ethyl acetate in hexanes) afforded tert-butyl 2-methyl-2-(1,3-thiazol-2-yl)propanoate (1.06 g, 62%) as a pale yellow oil. MS ESI: [M+H]+ m/z 228.1.
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