Patent GB-299064-A (GB)
Title: Method of producing sulphuric acid and/or halogen derivatives of formaldehyde
Filed: 1928-10-19
Abstract: 299,064. Fuchs, K., and Katscher, E. Oct. 21, 1927, [Convention date]. Dimethyl sulphate; methylene sulphate; chlormethyl sulphate; alpha-dichlordimethyl sulphate; chlormethyl, sulphate dichlor dimethyl ether; methylene chloride.-Halogen or sulphuric acid or halogen and sulphuric acid derivatives of " functional derivatives " of formaldehyde are produced by treating formaldehyde or its polymers or " functional derivatives " with halogen sulphonic acid, preferably chlorsulphonic acid or its salts, esters, or components. " Functional derivatives " of formaldehyde are defined as substances containing CH2 not directly combined with carbon or hydrogen, such as methylene ethers, dichlor dimethyl ether, methylene esters such as the dichloride, sulphate and acetate. The organic body may be treated with hydrohalogen acid and then with sulphur trioxide or fuming sulphuric acid, pyrosulphates, or mixtures of these products with or without solvents. Para. formaldehyde is treated with chlorsulphonic acid and the product distilled in vacuo, methylene chloride distilling below 50‹ C. and being condensed in a receiver cooled by carbonic acid and acetone, and chlormethyl sulphate, chloride, ClCH2OSO2Cl distilling at 50-60‹ C. which is purified by ice and water followed by washing with sodium bicarbonate solution and drying with sodium sulphate. The residue in the still is a viscous oil which after washing with water and then with alcohol yields methylene sulphate. In another example paraformaldehyde is mixed with a larger quantity of chlorsulphonic acid and the mixture is distilled in vacuo, yielding chlormethyl sulphate chloride. In another example formaldehyde is mixed with chlorsulphonic acid at 70-80‹ and the cold product poured on to ice, the separated oil being distilled up to 180‹ C. yielding a distillate of mainly s-dichlor dimethyl ether; on further distillation in vacuo, a small quantity of chlormethyl sulphate chloride distils, followed by dichlor dimethyl sulphate. In another example paraformaldehyde is treated with chlorsulphonic acid and sodium chloride is added, the mixture separating into layers, the top layer yielding dichlor dimethyl ether and dichlor dimethyl sulphate; the mixture may also be distilled after adding the sodium chloride, yielding the same products. In another example dichlor dimethyl sulphate is treated with chlorsulphonic acid at 70-80‹ C. and distilled in vacuo, yielding a distillate of chlormethyl sulphate chloride and a residue containing methylene. sulphate. In another example methylene sulphate is treated with chlorsulphonic acid and the mixture is distilled in vacuo at 50-60‹ C. yielding chlormethyl sulphate chloride. In another example s-dichlordimethyl ether is treated with chlorsulphonic acid and heated to 70‹ C., the cooled mixture being distilled in vacuo yielding chlormethyl sulphate chloride. In another example methylene chloride is treated with chlorsulphonic acid and heated to 60-150‹ C., vacuum distillation yielding chlormethyl sulphate chloride. The Specification as open to inspection under Sect. 91. (3) (a) also include's Schiff's bases of formaldehyde as functional derivatives and states that sulphuric acid derivatives such as methylene sulphate may be converted to derivatives containing halogen and sulphuric acid or halogen only by treatment with hydrohalogen acids or their salts or acid salts with or without solvents. This subject-matter does not appear in the Speci. fication as accepted.