850. ------. [GRESHAM, W. F.] (E. I. du Pont de Nemours & Co.). Esters of Cyclic Acetals and Carbon Monoxide. United States Patent 2,364,438. Dec. 5, 1944. Chem. Abs., vol. 39. 1945. p. 4632.

Patent Abstracts

Of particular interest is the reaction product of 1,3-dioxolane and CO. The reaction is carried out at a wide range of temperatures, under superatmospheric pressures of CO and in the presence of an acid catalyst. Suitable catalysts are inorganic acids (HCl, H₂SO₄, and H₃PO₄), inorganic acid salts, nonmetal halides, such as BF₃, as well as organic acids. The product is cooled on an ice bath, H₂SO₄ 53 is added to 1.3-dioxolane 175 parts. The polymerized dioxolane is placed in a Ag-lined pressure vessel, CO added under 200-700 atm., and the temperature raised to 88º-122º. The product is dissolved in a MeOH-Et₂O mixture, neutralized with Na₂CO₃, and the Na₂SO₄ formed filtered off. The excess Et₂O is evaporated, 3 parts of H₂SO₄ and enough MeOH to bring it to 400 parts are added: this is boiled for 2 hr. to esterfy, neutralized with NaOMe, and fractionated. The Me (2-hydroxyethoxy) acetate, HOCH₂CH₂OCH₂CO₂Me, b1 64º-69º was a saponification number of 420. In place of dioxolane, dioxanes, dioxins, various other related compounds, and their polymers can be used.