植酸-铪纳米酸性催化剂的制备及其立体选择性合成反式茴香脑的研究

Preparation of Phytate-Hafnium Acid Catalyst and Its Stereoselective Synthesis of Trans-Anethole

生物质能源作为一种储量丰富、来源广泛、环境友好的绿色能源,可有效代替不可再生的化石能源。以生物质基4-甲氧基苯丙酮(4-methoxyphenylacetone)为底物,在Lewis/Br nsted双功能酸催化剂的作用下,通过一锅级联氢化和脱水反应实现立体选择性多米诺催化合成反式茴香脑。对PA-Hf(1∶2.5)催化剂进行X-射线衍射(XRD)、物理吸附(BET)、傅里叶变换红外光谱(FT-IR)、热重分析(TG)、扫描电镜(SEM)、透射电镜(TEM)等一系列表征,用于测量其物理及化学性质。结果表明:PA-Hf(1∶2.5)催化剂具有良好的催化性能和化学稳定性,反式茴香脑的产率可达80.0%。机理研究证明,Lewis酸位点对4-甲氧基苯丙酮的MPV还原反应至关重要,而Br nsted酸位点可以有效促进后续的脱水反应。该催化剂经过5次循环使用后,仍能稳定高产率获得茴香脑。PA-Hf(1∶2.5)良好的稳定性和重复使用性使其在多米诺级联生产茴香脑的新路线中表现出很好的应用前景。

As a kind of green energy with abundant reserves,wide sources and environmental friendliness,biomass energy can effectively replace non-renewable fossil energy.In this paper,biomass-derived 4-methoxy-phenylacetone was used as substrate for trans-anethole synthesis by one-pot hydrogenation and dehydration reaction under the action of Lewis/Br nsted bifunctional acid catalyst.In addition,XRD,BET,FT-IR,TG,SEM and TEM were used to measure the physical and chemical properties of PA-Hf(1∶2.5)catalyst.The results show that the PA-Hf(1∶2.5)catalyst have good catalytic performance and chemical stability,and the yield of trans-anethole could reach 80.0%.Mechanistic studies prove that the Lewis acid site is critical for the MPV reduction of 4-methoxyphenylacetone,while the Br nsted acid site is able to effectively promote the subsequent dehydration reaction.After 5 cycles,the catalyst is stable and could afford high yield of target product.Good stability and reusability of PA-Hf(1∶2.5)make it show a good application prospect in the new route of domino cascade production of anisole.