Triethylamine → {2-[3-(2-Fluoro-3-methoxy-phenyl)-2,4,6-trioxo-[1,3,5]triazinan-1-yl]-1,1-dimethyl-ethyl}-carbamic acid tert-butyl ester

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Reaction Steps

To 20 mL of anhydrous CH2Cl2 was added 0.93 g of {2-[3-(2-Fluoro-3-methoxy-phenyl)-ureido]-1,1-dimethyl-ethyl}-carbamic acid tert-butyl ester and triethylamine (1.0 eq, 0.36 mL). N-(chlorocarbonyl) isocyanate (1.0 eq, 0.11 mL) was added to the solution in one portion. The reaction stalled after one hour, so additional triethylamine (1.0 eq, 0.36 mL) and N-(chlorocarbonyl) isocyanate was added. The reaction was determined to be complete by LC/MS after two hours. Excess isocyanate was quenched with the dropwise addition of H2O (1 mL). The reaction was then diluted with 20 mL H2O, and the organic layer was collected. The aqueous layer was extracted with CH2Cl2 (2×20 mL). The combined organics were washed with brine, dried over Na2SO4, filtered, and concentrated in vacuo. The residue was purified via flash column chromatography and eluted with 60% EtOAc/hexanes to yield 0.65 g (59%). Rf=0.66 in 60% EtOAc/hexanes. 1H NMR (CDCl3) δ: 7.19 (dt,1H), 7.09 (dt,1H), 6.90 (dt,1H), 5.15 (ds,1H), 4.1 (q,2H), 3.92 (s,3H), 1.42 (s,9H), 1.38 (d,6H).

Provenance & Evidence