1-(4-FLUORONAPHTHYL) TRIFLUOROMETHYL KETONE synthesis

Yield:-

Reaction Conditions:

with n-butyllithium in tetrahydrofuran;hexane at -78 - 20; for 1.16667 h;

Steps:

73 Reference Example 73

Reference Example 73 To a mixture of 1-bromo-4-fluoronaphthalene (1.57 g) and tetrahydrofuran (30 mL) was added at -78°C a 1.6 Mn - butyllithium - hexane solution (4.8 mL). The mixture was stirred for 20 minutes, and then added to a mixture of ethyl trifluoroacetate (1.7 mL) and tetrahydrofuran (20 mL) at the same temperature. After stirring for 20 minutes, the mixture was stirred for 30 minutes with elevating to room temperature. The reactant was poured into brine and extracted with ethyl acetate. The extracts were washed with brine, dried and concentrated. The obtained residue was purified by silica gel column chromatography to obtain 2,2,2-trifluoro-1-(4-fluoro-1-naphthyl)ethanone (865 mg). ¹H-NMR (300 MHz, CDCl₃) δ: 7.25 (1H, dd, J=9.6 and 8.4 Hz), 7.69 (1H, ddd, J=8.4, 6.9 and 1.2 Hz), 7.79 (1H, ddd, J=8.4, 6.9 and 1.8 Hz), 8.21-8.27 (2H, m), 8.95-8.99 (1H, m).

References:

EP1553074,2005,A1 Location in patent:Page/Page column 50