Highly Efficient Alkene Epoxidation and Aziridination Catalyzed by Iron(II) Salt + 4,4′,4′′-Trichloro-2,2′:6′,2′′-terpyridine/4,4′′-Dichloro-4′-<i>O</i>-PEG-OCH<sub>3</sub>-2,2′:6′,2′′-terpyridine
作者:Peng Liu、Ella Lai-Ming Wong、Angella Wing-Hoi Yuen、Chi-Ming Che
DOI:10.1021/ol801157m
日期:2008.8.7
"Iron(II) salt + 4,4',4"-trichloro-2,2':6',2"-terpyridine" is an effective catalyst for epoxidation and aziridination of alkenes and intramolecular amidation of sulfamate esters. The epoxidation of allylic-substituted cycloalkenes achieved excellent diastereoselectivities up to 90%. ESI-MS results supported the formation of iron-oxo and -imido intermediates. Derivitization of Cl(3)terpy to O-PEG-OCH3-Cl(2)terpy renders the terpyridine unit to be recyclable, and the "iron(II) salt + 4,4"-dichloro-4'-O-PEG-OCH3-2,2':6',2"-terpyridine" protocol can be reused without a significant loss of catalytic activity in the alkene epoxidation.
**翻译:**
“亚铁盐 + 4,4',4"-三氯-2,2':6',2"-三联吡啶”是烯烃环氧化、氮氧化及磺酰胺酯类分子内酰胺化反应的有效催化剂。对环烯烃的环氧化反应表现出优异的非对映异构选择性,最高可达90%。电喷雾电离质谱(ESI-MS)结果支持了亚铁氧和亚铁亚胺中间体的形成。将Cl₃terpy衍生成O-PEG-OCH₃-Cl₂terpy,使三联吡啶结构单元可循环利用,而“亚铁盐 + 4,4'-二氯-4'-O-PEG-OCH₃-2,2':6',2"-三联吡啶”催化体系在烯烃环氧化反应中可重复使用,且催化活性无显著降低。