Hydrochloric Acid → HCID 20042847, compound

Participants

Reaction Conditions

Reaction Steps

To the toluene filtrate were added at room temperature 450 ml of 2N sodium hydroxide and the reaction mixture was gradually heated to reflux to minimize initial foaming. The reaction was heated at reflux for 41/2 hours. The reaction mixture was cooled to 0° to 5° C. by an ice-water bath whereupon a thick precipitate formed, consisting of the intermediate sodium 4-(3,5-di-tert-butyl-4-hydroxybenzoyloxy)-3,5-di-tert-butyl-benzoate. This compound was a white solid which did not melt at 300° C. 70 ml of concentrated aqueous hydrochloric acid was gradually added dropwise with cooling at 30° C. 150 ml of ether were added with stirring to the reaction mixture at 20° to 25° C. The aqueous phase was separated and the organic phase washed with two 100 ml portions of water. The separated organic phase was then dried over anhydrous sodium sulfate. The residue was isolated from the organic phase by evaporation of the solvent initially at about 20 mm. Hg. pressure and finally at 0.5 mm. Hg. The glassy residue was ground and then triturated with stirring at reflux with a 150 ml. portion of petroleum ether in a 3-neck flask. The slurry was then cooled to room temperature, the solid isolated by filtration and triturated once again. The white crystalline precipitate from the second trituration was dried in the vacuum oven overnight at 40° C. at 1 mm. Hg. pressure. The product was isolated as a white powder weighing 102 grams (84.5% yield). The product melted at about 301° to 306° C., the melting range depending on the heating rate.

Provenance & Evidence