Ethanol, 1-ethoxy-2,2,2-trifluoro- → HCID 68224079, compound

Participants

Reaction Steps

A solution of 11 (2 g, 3.62 mmol), PTSA monohydrate (0.76 g, 3.98 mmol) and trifluoroacetaldehyde ethyl hemiacetal (2.38 mL, 18.11 mmol) in EtOH (50 mL) was heated to reflux overnight. More trifluoroacetaldehyde ethyl hemiacetal (1.2 mL, 9.13 mmol) was added and the reaction mixture was heated to reflux overnight. Once again, more trifluoroacetaldehyde ethyl hemiacetal (2 mL, 15.22 mmol) were added and the reaction mixture was heated to reflux overnight. Finally, another portion of trifluoroacetaldehyde ethyl hemiacetal (2 mL, 15.22 mmol) and PTSA monohydrate (0.76 g, 3.98 mmol) were added and the reaction mixture was heated to reflux for 5 days. The reaction mixture was concentrated and partitioned between AcOEt and water. The organic layer was successively washed with a saturated aqueous solution of sodium bicarbonate and brine, dried over anhydrous magnesium sulfate, filtered and concentrated. The residue was purified by Biotage (SNAP 100 g cartridge; MeOH/DCM: 0/100 to 10/90 over 20 CV), to afford the title compound 14 (1.519 g, 2.76 mmol, 76% yield) as a pale orange sticky solid. 1H NMR (400 MHz, DMSO-d6) δ (ppm): 8.56 (d, J=1.4 Hz, 1H), 8.50 (d, J=5.5 Hz, 1H), 8.30 (s, 1H), 8.22 (d, J=8.0 Hz, 1H), 7.89 (dd, J=8.0, 2.2 Hz, 1H), 7.31 (t, J=9.1 Hz, 1H), 7.11-7.02 (m, 2H), 6.87 (dd, J=9.0, 1.8 Hz, 1H), 6.62 (dd, J=5.3, 0.8 Hz, 1H), 5.73-5.64 (m, 1H), 3.78 (s, 2H), 3.77-3.59 (m, 2H), 3.41 (t, J=5.7 Hz, 2H), 3.24 (s, 3H), 2.65 (t, J=5.7 Hz, 2H), 1.15 (t, J=7.0 Hz, 31-1), one NH proton is missing. MS (m/z): 551.6 (M+H).

Provenance & Evidence