Synthetic, spectral and catalytic activity studies of ruthenium bipyridine and terpyridine complexes: Implications in the mechanism of the ruthenium(pyridine-2,6-bisoxazoline)(pyridine-2,6-dicarboxylate)-catalyzed asymmetric epoxidation of olefins utilizing H2O2
作者:Man Kin Tse、Haijun Jiao、Gopinathan Anilkumar、Bianca Bitterlich、Feyissa Gadissa Gelalcha、Matthias Beller
DOI:10.1016/j.jorganchem.2005.12.069
日期:2006.10
6-[(4S)-4-phenyl-4,5-dihydro-oxazol-2-yl]-[2,2′]bipyridinyl new insights on the reaction intermediates and reaction pathway of the ruthenium-catalyzed enantioselective epoxidation are proposed. In addition, a simplified protocol for epoxidation of olefins using urea hydrogen peroxide complex as oxidizing agent has been developed.
各种Ru(L 1)(L 2)(1)配合物(L 1 = 2,2'-联吡啶,2,2':6',2''-吡啶,6-(4 S)-4-苯基-4 ,5-二氢-恶唑-2-基-2,2'-联吡啶基或2,2'-联吡啶基-6-羧酸酯; L 2 =吡啶-2,6-二羧酸酯,吡啶-2-羧酸吡啶或2,2' -联吡啶基-6-羧酸盐)(已合成(或原位生成)),并使用30%的H 2 O 2水溶液对烯烃进行环氧化测试。含有2,6-二羧酸吡啶的配合物显示出极高的催化活性。基于包含非外消旋2,2'-联吡啶(包括6-[(4 S)-4-苯基-4,5-二氢-恶唑-2-基]-[2,2']联吡啶基对钌催化的对映选择性环氧化反应的中间体和反应途径提出了新的见解。另外,已经开发出使用过氧化氢脲配合物作为氧化剂的烯烃环氧化的简化方案。