Revisiting of Benzophenone Ketyl Still: Use of a Sodium Dispersion for the Preparation of Anhydrous Solvents

A facile generation of organic solvents of anhydrous grade can be performed by distillation from sodium-benzophenone ketyl, which is prepared from commercial sodium dispersion and benzophenone. The distilled tetrahydrofuran, diethyl ether, hexane, 1,2-dimethoxyethane, and 1,4-dioxane with water contents less than 10 ppm were obtained by a simple protocol. Safe treatment of the distillation residue also was simply achieved by the addition of methanol. The protocol suits for providing a small amount of an anhydrous solvent at the laboratory scale.