Water → HCID 178455734, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 2.87 g of 4-[2-[trans-4-(2,2-dibromovinyl)cyclohexyl]ethyl]-4'-pentylbiphenyl in 100 ml of absolute tetrahydrofuran was placed at -20° C. in a sulphonation flask under argon gasification and treated within 15 minutes with 20.6 ml of a 0.8N solution of butyl lithium in hexane (slight exothermic reaction). The mixture was subsequently stirred for a further 1.5 hours with gradual warming to 0° C., then poured into 100 ml of water and extracted three times with 100 ml of diethyl ether each time. The organic phases were washed a further twice with 100 ml of water each time, dried over magnesium sulphate and concentrated. Low-pressure chromatography (0.5 bar) of the residue (1.98 g) on silica gel with 1% ethyl acetate/petroleum ether as the eluant gave 1.94 g (98%) of 4-[2-(trans-4-ethynylcyclohexyl)ethyl]-4'-pentylbiphenyl. Two-fold recrystallization from ethanol and repeated low-pressure chromatography (0.5 bar) of the crystallizate on silica gel with hexane as the eluant finally yielded 732 mg of mixed fractions and 684 mg of pure 4-(2-(trans-4-ethynylcyclohexyl)ethyl]-4'-pentylbiphenyl with m.p. (C-S) 66.0° C., t.p. (S-S) 107° C., t.p. (S-N) 115.5° C. and cl.p. (N-I) 126.4° C.

Provenance & Evidence