Tetrahydrofuran → HCID 178444460, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 750 mg of trans-1-ethynyl-4-[2-(trans-4-pentylcyclohexyl)ethyl]cyclohexane (prepared according to Example 14) in 75 ml of a 4:1 mixture of absolute tetrahydrofuran and hexamethylphosphoric acid triamide was placed at -45° C. in a sulphonation flask under argon gasification and treated within 2 minutes with 3.3 ml of a 1.0N solution of butyl lithium in hexane. The mixture was subsequently stirred at -20° C. for a further 1 hour, then cooled to -78° C. and treated with 490 μl of phenyl cyanate in a single portion. The mixture was then stirred at -78° C. for a further 2.5 hours, poured into 200 ml of water and extracted three times with 150 ml of diethyl ether each time. The organic phases were washed twice with 150 ml of water each time and once with 100 ml of saturated sodium chloride solution, dried over magnesium sulphate and concentrated. Low-pressure chromatography (0.5 bar) of the residue (2.6 g) on silica gel with hexane gave in sequence 194 mg (25.8%) of trans-1-ethynyl-4-[2-(trans-4-pentylcyclohexyl)ethyl]cyclohexane and 284 mg (34.8%) of trans-4-[2-(trans-4-pentylcyclohexyl)ethyl]cyclohexanepropiolonitrile (purity 98.9%). A recrystallization of the nitrile from methanol yielded colourless crystals (purity 99.4%); m.p. (C-N) 51.4% and cl.p. (N-I) 112.7° C.

Provenance & Evidence