| Difunctionalization has become a powerful tool for the synthesis of natural products and active pharmaceutical ingredients.Alkene dioxygenation has been elegantly demonstrated with various transition metal catalysts,such as epoxidation and dihydroxylation.As one member of transition metal,iron is cheap,abundant,and low in toxicity;thus,iron-catalyzed organic reactions have attracted more attention than reactions catalyzed by precious metals,such as Pt,Rh,Ru,Mn,and Pd.Olefin epioxidation catalyzed or promoted by Fe-based complexes has been recently developed and radical difunctionalization has attracted increasing attention in recent years because of its mild conditions,high selectivity,and convenient workup.Whereas,the deficiencies in reports relevant to iron-inorganic salt catalyzing alkene deoxygenation limit the consummation of this system,which will stimulate interest of many research groups.This paper presents a nitrogen related FeCl3-catalyzed dioxygenation of aryl alkenes.Features of this kind reaction include: 1)mild reaction conditions;2)using green and atom efficient O2 as the oxidant;3)synthesizing a series of β-keto-N-alkoxyphthalimides;4)succeeding in application of this kind of ketones.We report the successful development of an intermolecular direct aerobic dioxygenation of styrenes employing N-hydroxyphthalimide（NHPI）.The aerobic oxidation of styrenes is catalyzed by FeCl3 to form over 30 amounts of β-keto-N-alkoxyphthalimides in CH3CN or CH3CN/H2 O.This reaction employs mild conditions that use green and atom efficient O2 as the oxidant.All compounds have been confirmed by 1H NMR,13 C NMR,MS and HR-MS.In order to ascertain the reaction’s mechanism,we utilize acetonitrile and H218O to conduct this aerobic dioxygenation reaction.Furthermore,the application of β-keto-N-alkoxyphthalimides was developed by attempt to remove the PINO group and some reduced products and halogenide were obtained. |
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