Ethylene Glycol → (1-Allylcyclohexyl)benzene

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-allyl-2-phenylcyclohexanone (1.97 g, 9.19 mmol) in ethylene glycol (8 mL, 143 mmol) were added hydrazine (0.8 mL, 25.5 mmol) and potassium hydroxide (1.547 g, 27.6 mmol), and the mixture was stirred at 100° C. for 1 hr and refluxed in a 180° C. oil bath for 2.5 hrs. TLC showed that the hydrazone formation nearly complete. Then the excess hydrazine and water were distilled out in a 200° C. oil bath, and it was continued to heat at the same temperature for 4 hrs. After cooling to room temp it was added to ether and washed with water and brine. The combined aqueous layers were back-extracted with ether (2×) and combined. Dried over Na2SO4 and evaporated to give an oily residue. It was purified by Combiflash (80 g silica gel) eluting with hexane followed by 5:95 EtOAc-hexane to give product (825 mg). 1H NMR (400 MHz, CCl3D) δ ppm 7.31 (4H, d, J=4.39 Hz), 7.17 (1H, dq, J=4.39, 4.25 Hz), 5.32-5.45 (1H, m), 4.89 (1H, s), 4.83-4.87 (1H, m), 2.26 (2H, d, J=7.47 Hz), 2.07 (2H, dd, J=13.84, 6.59 Hz), 1.33-1.63 (8H, m).

Provenance & Evidence