3-(hydroxyphenylphosphinyl) propionic acid ( CEPPA) was synthesized by a two-step procedure; Phenyl phosphonic dichloride ( DCPP) was first synthesized using phosphorus trichloride and benzene as raw materials, and tri-ethyl benzyl ammonium chloride-aluminum chloride ( [ BnEt3N]Cl -xA1C13 )as catalyst. The optimum conditions for the first step are as follows: re ( PC13 ) :n( C6 H6 ) :n( [ BnEt3 N ] Cl - xA1C13 ) = 3:1:0.025, At the reflux stage, the reaction temperature was 72℃-76℃, the reaction time was 6 h, and the yield of DCPP was up to 81. 1% . The optimum conditions for the second step by changing the order of the reactants and adjusting the reaction temperature were as follows; re (acrylic acid): n( DCPP) = 1. 30: 1. 00; the reaction temperature was 70℃ -80℃ and the reaction time was 1. 5 h -2h at the dropping stage; then reacting at 90℃ for 1 h; at the hydrolysis reaction stage, the reaction temperature was 92℃ - 95℃ , and the reaction time was 4 h, the yield of CEPPA was up to 91 %. The problem of agglomeration was easy to be solved in this procedure.%采用两步法合成3-羟基苯膦酰丙酸(CEPPA),即以三氯化磷与苯为原料,在离子液体三乙基苄基氯化铵氯化铝([ BnEt3N]Cl - xAlCl3)催化下,合成苯膦二氯(DCPP),再用DCPP与丙烯酸合成3-羟基苯膦酰丙酸(CEPPA).确定第一步最佳反应条件为:n(三氯化磷)∶n(苯)∶n([BnEt3N]Cl - xAlCl3)=3∶1∶0.025,同流温度为72℃～ 76℃,反应时间为6h,产率达81.1％；第二步通过改变反应物滴加顺序及调整反应温度,得到最佳反应条件为:n(丙烯酸)∶n(DCPP)=1.30∶1.00；滴加反应阶段,控制在70℃～80℃,反应1.5 ～2h后,在90℃保温反应1h；水解反应阶段,控制在92℃～95℃反应4h,CEPPA的产率可达91％,并解决了反应中易结块问题.
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