Ethyl chloroformate → N-carbonylethoxy-N-{4-chloro-2-[1-(4-fluorophenoxyimino)ethyl]phenyl}trifluoromethanesulfonamide

Participants

Reaction Steps

To a mixture of N-{4-chloro-2-[1-(4-fluorophenoxyimino)ethyl]phenyl}trifluoromethanesulfonamide (compound 129) (150 mg, 0.37 mmol) and K2CO3 (151 mg, 1.10 mmol) in acetone (5 mL) was added ethyl chloroformate (105 μL, 1.10 mmol), and the reaction allowed to stir at RT for 21 hours. The reaction mixture was concentrated under vacuum and the residue dissolved in Et2O (50 mL), washed with H2O (40 mL) then brine (40 mL), dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by radial thin layer chromatography (eluting with EtOAc/PE, 1:19) to afford N-carbonylethoxy-N-{4-chloro-2-[1-(4-fluorophenoxyimino)ethyl]phenyl}trifluoromethanesulfonamide 310 (85 mg, 63% based on recovered starting material), as a pale yellow oil, 1H n.m.r. (400 MHz, CDCl3) δ 7.52, d, J=2.4 Hz, 1H, 7.45, dd, J=2.4 and 8.8 Hz, 1H, 7.26, d, J=2.4 Hz, 1H, 7.14, m, 2H, 6.98, m, 2H; 4.24, m, 1H, 4.15, m, 1H, 2.41, s, 3H, 1.15, t, J=7.2 Hz, 3H. HRMS (M+) 482.0316.

Provenance & Evidence