Platinum-catalysed aerobic 1,2-aminooxygenation of alkenes
作者:Kilian Muñiz、Alvaro Iglesias、Yewen Fang
DOI:10.1039/b912139k
日期:——
Platinum(II) salts in combination with copper salts and molecular oxygen catalyse an unprecedented intramolecular transfer of heteroatoms to alkenes to yield aminooxygenation products under sustainable conditions.
Metal-Free Oxidative Cyclization of Urea-Tethered Alkenes with Hypervalent Iodine
作者:Brian M. Cochran、Forrest E. Michael
DOI:10.1021/ol8022165
日期:2008.11.6
A metal-free oxidative cyclization of ureas onto unactivated alkenes using iodosylbenzene and an acid promoter is described. The products isolated are predominantly bicyclic isoureas resulting from an intramolecular oxyamination reaction. The acid type and urea substitution have a strong effect on the product formed. A variety of substrates form the isourea with high diastereoselectivity via syn addition
Intramolecular diamination and alkoxyamination of alkenes with N-sulfonyl ureas employing N-iodosuccinimide
作者:Hao Li、Ross A. Widenhoefer
DOI:10.1016/j.tet.2010.03.082
日期:2010.6
Reaction of N-delta-alkenyl-N'-sulfonyl urea 1 with N-iodosuccinimde (NIS; 2 equiv) and a catalytic amount of AgOTf (20 mol %) at room temperature led to intramolecular alkoxyamination to form bicyclic isourea 2a in 95% isolated yield. In comparison, reaction of 1 with NIS and sodium bicarbonate (1 equiv) at room temperature led to isolation of bicyclic imidazolidin-2-one 2b in 91% yield. These NIS-mediated alkoxyamination and diamination protocols were effective for a range of N-delta-alkenyl-N'-sulfonyl ureas to form the corresponding heterobicyclic compounds in good yield with high chemoselectivity and good to excellent diastereoselectivity. (C) 2010 Published by Elsevier Ltd.