| 摘要 |
1,127,117. Aliphatic Schiff bases. KANEGAFUCHI BOSEKI K.K. 13 April, 1966 [14 April, 1965], No. 16268/66. Heading C2C. [Also in Division B1] Aliphatic Schiff bases are obtained by continuously contacting at a temperature of from 320‹ to 550‹ C., a 5 to 13 membered lactam, in the gaseous phase, with solid particles of an oxide or hydroxide of an alkali metal or alkaline earth metal, or a mixture thereof, as a decarbonation-condensing agent. The reaction may be effected in a continuous manner and the decarbonation agent (which may be mixed with an inert gas, e.g. nitrogen) may be employed in the form of a fluidized or moving bed. The lactam is vaporized and generally fed to the fluidized or moving bed in admixture with an inert gas, e.g. nitrogen. After reaction the gas stream is separated from solid particles and the product is obtained either by condensing the gas stream or by dissolving it in a solvent, e.g. water, an organic solvent or a mixture thereof. The product may be purified by converting it into the carbonate of the corresponding diamino ketone by reaction in an inert organic solvent with carbonic acid gas, liquid carbon dioxide or dry ice, and subsequently heating the carbonate to recover the Schiff's base. Specified lactam starting materials are #- laurolactam, #-caprylolactam, #-enantholactam, 5-methyl-#-caprolactam, #-caprolactam and α-pyrrolidone. Specified decarbonation-con - densing agents are the oxides of calcium, barium and magnesium, calcium hydroxide and sodalime. |
