碘掺杂聚苯胺催化剂催化合成缩醛(酮)

制备出单质碘掺杂聚苯胺催化剂I2/PAn,并以I2/PAn为催化剂对以乙酰乙酸乙酯、环己酮、丁酮、苯甲醛和正丁醛与二元醇(乙二醇,1,2-丙二醇)为原料合成10种缩醛(酮)的反应条件进行了研究,重点考察了影响苯甲醛1,2-丙二醇缩醛合成的各种因素.在确定的n(醛/酮):n(乙二醇/1,2-丙二醇)=1:1.6(物质的量的比),催化剂的用量占反应物料总质量的0.2%,反应时间为1 h条件下,10种缩醛(酮)的收率在47.3%～94.2%之间.

Catalytic synthesis of acetals and ketals with I2/Pan

A new environmental friendly catalyst, I2/Pan, was prepared. The catalytic activities of I2/ PAn in synthesizing 2-methyl-2-ethoxycarbonylmethyl-1, 3-dioxolane, 2, 4-dimethyl-2-ethoxycarhonylmethyl-1, 3-dioxolane, cyclohexanone ethylene ketal, cyclohexanone 1, 2-propanediol ketal, butanone ethylene ketal, butanone 1, 2-propanediol ketal, 2-phenyl-1, 3-dioxolane, 4-methyl-2-phenyl-1, 3-dioxolane, 2-propyl-1, 3-dioxolane, and 4-methyl-2-propyl-1, 3-dioxolane were reported. It is demonstrated that I2/PAn is an excellent catalyst. Various factors concerned in these reactions were investigated. An optimum condition was found, that is, the molar ratio of aldehyde/ketone to glycol is 1/1.6, the mass ratio of the catalyst used to the reactants is 0.2 %, and the reaction time is 1.0 h. Under the optimum condition, the yields of these 10 kinds of acetals/ketals are 47.3 % -94.2 %.