Thionyl Chloride → HCID 88189866, compound

Participants

Reaction Steps

65 g (0.2 mol) of the above tosyl ester were added to a solution of 36.5 g (0.24 mol) of potassium tert-butoxide dissolved in tert-butanol, and the mixture was warmed to reflux with stirring and stirred under reflux for 8.5 hours. After cooling, the mixture was hydrolyzed and extracted with methyl tert-butyl ether, and the organic phase was washed (twice with water), dried and evaporated. The residue was again partitioned between 2 N NaOH and methyl tert-butyl ether, and the purification procedure was repeated, giving 37 g (60%) of methyl 4-(but-3-enylcyclohexylmethoxy)benzoate. This ester was hydrolyzed in a conventional manner using KOH/methanol to give the free acid, which was reacted with thionyl chloride to give 4-(but-3-enylcyclohexylmethoxy)benzoyl chloride. 18 g (0.06 mol) of this acid chloride and 10.0 g (0.063 mol) of commercial 1,4-butanediol monomethacrylate (Polysciences, D-69208 Eppelheim) were dissolved in 15 ml of toluene, and a solution of 6.1 g (0.067 mol) of triethylamine dissolved in 40 ml of toluene was added dropwise over the course of 5 minutes. The mixture was stirred at 50° C. for 30 minutes, warmed to 80° C., and stirred at this temperature for a further 2 hours. The mixture was then cooled, and the precipitated amine hydrochloride was filtered off, washed with 0.5 N hydrochloric acid and then with water, dried and evaporated. The residue was purified on a silica gel column. The target product had an m.p. of 22-25° C.

Provenance & Evidence