Zhao Shanshan, Zhao Jiquan, Zhao Dongmin
School of Chemical Engineering, Hebei University of Technology, Tianjin 300130, PR China.
Carbohydr Res. 2007 Feb 5;342(2):254-8. doi: 10.1016/j.carres.2006.11.026. Epub 2006 Dec 3.
Three new salen ligands with carbohydrate moieties were prepared from a salicylaldehyde derivative obtained by reaction of 1,2:5,6-di-O-isopropylidene-alpha-D-glucofuranose with 3-tert-butyl-5-(chloro-methyl)-2-hydroxybenzaldehyde. These ligands were coordinated with Mn(III) to give three chiral salen-Mn(III) complexes. The complexes were characterized and employed in the asymmetric epoxidation of unfunctionalized alkenes. Catalytic results showed that although there are no chiral groups on the diimine bridge, these complexes had some enantioselectivity, which indicates the carbohydrate moiety has an asymmetric inducing effect in the epoxidation reaction.
由1,2:5,6-二-O-异亚丙基-α-D-葡萄糖呋喃糖与3-叔丁基-5-(氯甲基)-2-羟基苯甲醛反应得到的水杨醛衍生物制备了三种带有碳水化合物部分的新型双水杨醛缩乙二胺配体。这些配体与Mn(III)配位得到三种手性双水杨醛缩乙二胺-Mn(III)配合物。对这些配合物进行了表征，并将其用于未官能化烯烃的不对称环氧化反应。催化结果表明，尽管二亚胺桥上没有手性基团，但这些配合物具有一定的对映选择性，这表明碳水化合物部分在环氧化反应中具有不对称诱导作用。
