Ammonium Chloride → HCID 11594476, compound

Participants

Reaction Conditions

Reaction Steps

n-Butyllithium (1.6M in hexanes, 1.76 mL, 2.83 mmol) was added dropwise to a stirred solution of 2-bromothiazole (462 mg, 251 μL, 2.82 mmol) in dry THF (13 mL) at −78° C. under N2 and the reaction was stirred at −78° C. for 45 min. Separately, isopropylmagnesium chloride (2M in THF, 0.94 mL, 1.99 mmol) was added to a stirred solution of benzyl {(1S)-2-[methoxy(methyl)amino]-1-methyl-2-oxoethyl}carbamate (500 mg, 1.88 mmol) in dry THF (4 mL) at −15° C. under N2. This solution was stirred for 15 min at −15° C. and was added dropwise to the above 2-lithiothiazole solution at −78° C. The reaction was allowed to warm to room temperature overnight and saturated NH4Cl (20 mL) and water (10 mL) were added and the mixture was extracted with EtOAc (3×30 mL). The combined extracts were washed with brine, dried (Na2SO4) and concentrated in vacuo to give the crude product. This was purified by flash chromatography (Si, 25×160 mm, 0-50% EtOAc in hexanes gradient) to afford benzyl [(1S)-1-methyl-2-oxo-2-(1,3-thiazol-2-yl)ethyl]carbamate. Rf=0.28 (20% EtOAc in hexanes). LCMS calc.=291.1; found=291.3 (M+1)+. 1H NMR (600 MHz, CDCl3) δ 8.03 (s, 1H), 7.70 (d, J=3.1 Hz, 1H), 7.34-7.29 (m, 5H), 5.79 (d, J=6.6 Hz, 1H), 5.53-5.49 (m, 1H), 5.14-5.08 (m, 2H), 1.55 (d, J=6.4 Hz, 3H).

Provenance & Evidence