Sulfuric Acid → HCID 19901371, compound

Participants

Reaction Steps

A solution of 2.82 g of 4'-(p-toluenesulphonyloxy)biphenyl-4-carboxaldehyde and 1.54 g of 2-hexyl-1,3-propane-diol in 50 ml of toluene was treated with 3 drops of 10% (vol.) sulphuric acid. The mixture was heated to boiling for 1.5 hours, with about 50 ml of damp toluene being distilled off and 30 ml of fresh toluene being simultaneously added dropwise. Then, 10 drops of triethylamine were added to the reaction mixture. After cooling the mixture was washed with 10 ml of lN sodium hydrogen carbonate solution and three times with 20 ml of water each time, dried over sodium sulphate and concentrated. The resulting crude 5-hexyl-2-[4'-(p-toluenesulphonyloxy)-4-biphenylyl]m-dioxane (4.26 g) was dissolved in 160 ml ethanol. The solution was treated with a solution of 2.64 g of potassium hydroxide in 27 ml of water and heated to boiling for 1.8 hours while stirring. After cooling the reaction mixture was neutralized (to pH 6) with 1.9 ml of glacial acetic acid and concentrated to about 20 ml. The suspension obtained was diluted with 80 ml of dichloromethane and the organic phase was washed twice with 20 ml of water each time, dried over sodium sulphate and concentrated. Chromatography of the residue (2.80 g) on g of silica gel with toluene/acetone (vol. 19:1) gave 1.94 g of 5-hexyl-2-(4'-hydroxy-4-biphenylyl)-m-dioxane.

Provenance & Evidence