2,4-Bis(trifluoromethyl)bromobenzene → HCID 59520444, compound

Participants

Reaction Conditions

Reaction Steps

(2-Hydroxy-ethyl)-carbamic acid tert-butyl ester (0.2 mL, 1.29 mmol) is dissolved in 3 mL dry dimethyl-acetamide. 2-Potassium-1,1,1,3,3,3-hexamethyl-disilazane (0.52 g, 2.6 mmol, 2 equiv.) is added, followed by 1-bromo-2,4-bis-trifluoromethyl-benzene 31 (0.26 mL, 1.5 mmol, 1.2 equiv.). The mixture is stirred at 60° C. under nitrogen for 18 hours. The mixture is cooled, diluted with 50 mL water and extracted with dichloromethane (3×50 mL). The combined organic extracts are washed with water and 10% aqueous citric acid, dried over Na2SO4 and concentration. Silica gel chromatography (5% to 25% ethyl acetate in hexanes) yielded [2-(2,4-Bis-trifluoromethyl-phenoxy)-ethyl]-carbamic acid tert-butyl ester 32 as a colorless, mobile oil: 1H-NMR (400 MHz, CDCl3) δ=7.61 (s, 1H), 7.00 (d, J=8 Hz, 1H), 6.76 (d, J=8 Hz, 1H), 5.10 (s, 1H), 4.26 (t, J=4 Hz, 2H), 3.65 (m, 2H), 1.45 (s, 9H). 19F-NMR (376 MHz, CDCl3) δ=−61.5, −62.0. No molecular ion could be obtained; a loss of tert-butyl group is observed: MS calculated for C11H10F6NO3 (M+H+—C4H8) 318.1, found 318.3.

Provenance & Evidence