| 摘要 |
1. A process for the preparation of 2,6-dimethylmorpholine containing a high proportion of the cis-isomer by cyclization of diisopropanolamine with sulfuric acid, working up the reaction mixture with sodium hydroxide solution, and distilling and drying the crude product obtained, wherein diisopropanolamine containing from 0 to 20 percent of water, and excess 90 to 120 percent strength sulfuric acid are simultaneously metered in such a manner into the reaction space, while stirring but without cooling, that the temperature of the reaction medium increases to 85 to 170 degrees C, and the reaction mixture is then heated at 150 to 190 degrees C for 1 to 25 hours while water is distilled off. |
