| 摘要 |
891,638. Chloralkyl esters of acrylic acid. BADISCHE ANILIN- & SODA-FABRIK A.G. April 1, 1960 [April 4, 1959], No. 11524/60. Class 2 (3). The invention comprises (4-chlor-n-butoxy)-nbutyl acrylate, 2,2-dimethyl-3-chlorpropyl acrylate. 2-(tris-chlormethyl)-ethyl acrylate and 2- chlorethoxyethyl acrylate. Chloralkyl esters of acrylate acid are made by reacting an acrylic acid chloride, which may be substituted in alpha- or beta-position by halogen or an alkyl radical containing 1 to 4 carbon atoms, with a cyclic ether containing only carbon and oxygen in a ring of at least 4 atoms, in the presence of an acidreacting catalyst. Suitable cyclic ethers are trimethylene oxide, 3,3-dimethyl-trimethyleneoxide, 3,3 - bis - (chlormethyl) - oxa - cyclobutane, tetrahydrofurane, tetrahydropyran, dihydropyran, and dioxane. Besides acrylic acid chloride, α-chlor- and α-brom-acrylic acid chlorides, methacrylic acid chloride, crotonic acid chloride and #-methylcrotonic acid chloride are mentioned. Acid reacting catalysts are aluminium chloride, tin tetrachloride, sulphuric acid or concentrated hydrochloric acid. The reaction proceeds to completion in the temperature range between 20‹C. and 150‹C. In order to avoid premature polymerization, it is advantageous to discontinue the reaction when a 50% to 70% conversion is attained and to distil off and re-use unreacted material. Continuous operation may be employed |
