Hydrochloric Acid → (E)-4-(1-(4-fluorophenyl)cyclohexyl)but-3-enoic acid

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a stirred suspension of 1-(4-fluorophenyl)cyclohexanecarbaldehyde (160 mg, 0.776 mmol) and 2-carboxyethyl triphenylphosphonium bromide (483 mg, 1.164 mmol) in THF (7 mL) at −78° C. was added 1M lithium bis(trimethylsilyl)amide (2.172 mL, 2.172 mmol) in THF dropwise, and the mixture was stirred for 30 mins at −78° C., and 30 mins at a temperatures in the range of from −78° C. to room temperature. Next, the mixture was stirred overnight at room temperature. After addition of 3 mL of 1N HCl, the mixture was extracted with EtOAc (2×), and the combined extracts were washed with brine, dried over Na2SO4 and evaporated to give an oily residue. The residue was purified by Combiflash (24 g silica gel) eluting with 5:95 followed by 3:7 EtOAc-hexane to give (E)-4-(1-(4-fluorophenyl)cyclohexyl)but-3-enoic acid (37.7 mg, 0.144 mmol, 18.53% yield) along with the unreacted starting material (41.5 mg). 1H NMR (400 MHz, CCl3D) δ ppm 7.28-7.33 (2H, m), 6.93-6.99 (2H, m), 5.97 (1H, dt, J=11.64, 1.76 Hz), 5.58 (1H, dt, J=11.64, 7.25 Hz), 2.59 (2H, dd, J=7.25, 1.76 Hz), 1.86-1.96 (2H, m), 1.54-1.76 (8H, m), 1.22-1.33 (2H, m).

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