Light-Sensitive Alkoxyamines as Versatile Spatially- and Temporally-Controlled Precursors of Alkyl Radicals and Nitroxides

Marc Baron (1) , Jason C. Morris (1) , Siham Telitel (2) , Jean-Louis Clément (1) , Jacques Lalevee (2) , Fabrice Morlet-Savary (2) , Arnaud Spangenberg (2) , Jean-Pierre Malval (2) , Olivier Soppera (2) , Didier Gigmes (1) , Yohann Guillaneuf (1)

1 ICR - Institut de Chimie Radicalaire
2 IS2M - Institut de Science des Matériaux de Mulhouse

The use of UV/visible light irradiation as a means to initiate organic syntheses is increasingly attractive due to the high spatial and temporal control conferred by photochemical processes. The aim of this work is thus to demonstrate that alkoxyamines bearing a chromophore on the alkyl moiety can provide a photoprotecting group for the sensitive nitroxide functionality, that is known to degrade through redox processes. The dissociation of various photosensitive alkoxyamines was studied from 223 to 298 K under UV/visible irradiation, depending on the nature of the chromophore. In each case a rapid (typically in less than 1 h) and near-quantitative dissociation was observed. As an illustration of the interest of this approach, a pyrene-based alkoxyamine was employed for the spatially controlled coupling of polymer chains onto Si wafers to produce micropatterned surfaces.

Mots clés: chemistry; cross-sections; functionalization; ligation; on bond homolysis; photo-generated thioaldehydes; photolabile protecting groups; polymers; science; surfaces; chemistry

Domaines: Chimie

Marc Baron, Jason C. Morris, Siham Telitel, Jean-Louis Clément, Jacques Lalevee, et al.. Light-Sensitive Alkoxyamines as Versatile Spatially- and Temporally-Controlled Precursors of Alkyl Radicals and Nitroxides. Journal of the American Chemical Society, 2018, 140 (9), pp.3339--3344. ⟨10.1021/jacs.7b12807⟩. ⟨hal-02091849⟩