Synthesis and catalytic properties of p-acylthio(phenylacetylene)n substituted chiral manganese salen complexes
作者:Morten Nielsen、Kurt V. Gothelf
DOI:10.1039/b104103g
日期:——
The syntheses of three new salen ligands that are tethered to a p-acylthio(phenylacetylene)n linker are described. The two key steps in the syntheses are coupling of the p-acylthio(phenylacetylene)n linker (n = 0–2) with a 5-iodosalicylaldehyde and the subsequent condensation of the aldehyde moiety of the formed adducts with the monoimine of (S,S)-1,2-diphenylethylenediamine to give the salen ligands. In the catalytic asymmetric epoxidation reactions of (Z)-2-methylstyrene, performed using the Mn–salen complexes of these new ligands, high diastereoselectivities of up to 20 ∶ 1 and enantioselectivities of up to 89% ee are obtained. The results are compared with the analogous reaction using Jacobsen's asymmetric epoxidation catalyst and the results are very similar. The synthesised ligands are promising candidates for the
immobilisation of chiral Mn–salen complexes on gold electrodes and surfaces.
描述了与对酰硫基(苯乙炔)n 连接体相连的三种新 salen 配体的合成。合成中的两个关键步骤是对酰硫基(苯乙炔)n 连接体(n = 0–2)与 5-碘水杨醛的偶联,以及随后形成的加合物的醛部分与 (S, S)-1,2-二苯基乙二胺得到salen配体。在使用这些新配体的 Mn-salen 配合物进行 (Z)-2-甲基苯乙烯的催化不对称环氧化反应中,获得了高达 20 ∶ 1 的高非对映选择性和高达 89% ee 的对映选择性。将结果与使用Jacobsen不对称环氧化催化剂的类似反应进行比较,结果非常相似。合成的配体是有希望的候选物
将手性 Mn-salen 配合物固定在金电极和表面上。