Metallfreie radikalische Azidoarylierung von Alkenen: schneller Zugang zu Oxindolen durch kaskadenförmige C‐N‐ und C‐C‐Bindungsbildung

Abstract

Eine neuartige Methode für die oxidative radikalische Azidierung von Alkenen unter Verwendung einer Kombination von Aziden mit hypervalenten Iodverbindungen besteht aus einer Kaskade von C‐N‐ und C‐C‐Verknüpfungsreaktionen. Sie resultiert in 2‐Oxindolen unter metallfreien Bedingungen bei hohen Reaktionsgeschwindigkeiten und Raumtemperatur und eröffnet den Zugang zu komplexen Produkten (siehe Schema; TMS=Trimethylsilyl).

Iodine(III)‐Mediated Diazidation and Azido‐oxyamination of Enamides

“…The more reactive PhenylIodine-bis(triFluoroAcetate) (PIFA) [27] was found to be as uitable promoter when it was used in conjunction with TMSN 3 in dichloromethane to access the bis-azido compound 5a in 19 %y ield (entry 6). Running the reaction in acetonitrile did not help to improvet he reactivity (entry 7), whereas bis(tert-butylcarbonyloxy)iodobenzene acted as as uperior promoter (entry 8), and it could also be used with LiN 3 (entries 9a nd 10).…”

Recent advances in the C–H-functionalization of the distal positions in pyridines and quinolines

“…2 In pyridines, quinolines, and other structurally-related N -heterocycles, the C2 position can be readily functionalized using a variety of transition metal-catalyzed reactions with Pd, 3,4 Cu, 5 Ni, 6 Rh, 7 Ru, 8 Fe, 9 and Ag 10 as catalysts, as well as by means of non-catalytic approaches. 11 The facility of the C2–H-functionalization is due to the favourable electronic factors, e.g. increased acidity of the C2–H bond and increased electrophilic character of the C2=N moiety; and due to the proximity of the nitrogen atom (or oxygen in the N -oxides) that can serve as a directing group.…”