Triethylamine → (3-Fluoro-5-morpholin-4-yl-phenyl)-carbamic acid 2,2,2-trichloro-ethyl ester

2,2,2-Trichloroethyl chloroformate (1.05 mL, 7.65 mmol) was added to an ice cold solution of 3-fluoro-5-morpholin-4-ylaniline (reference procedure see EP1102743; 1.0 g, 5.10 mmol) and triethylamine (1.77 mL, 10.2 mmol) in THF (25 mL). The reaction mixture was stirred at RT for 1.5 h, then quenched with water. The aqueous layer was extracted with EtOAc (×3) and the combined organic layers were washed with brine, dried (MgSO4) and concentrated in vacuo to afford the title compound (1.89 g, 99%) as a clear oil. LCMS (Method 3): Rt 3.75 min, m/z 371, 373 [MH+].