Formation of N-heterocyclic carbene-boryl radicals through electrochemical and photochemical cleavage of the B-S bond in N-heterocyclic carbene-boryl sulfides.

Sofia Telitel , Anne-Laure Vallet , Stéphane Schweizer , Bernard Delpech (1) , Nicolas Blanchard , Fabrice Morlet-Savary , Bernadette Graff , Dennis P Curran , Marc Robert , Emmanuel Lacôte , Jacques Lalevée

1 ICSN - Institut de Chimie des Substances Naturelles

The B-S bond in N-heterocyclic carbene (NHC)-boryl sulfides can be cleaved homolytically to NHC-boryl or NHC-thioboryl and thiyl radicals using light, either directly around 300 nm or with a sensitizer at a longer wavelength (>340 nm). In contrast, the electrochemical reductive cleavage of the B-S bond is difficult. This easy photolytic cleavage makes the NHC-boryl sulfides good type I photopolymerization initiators for the polymerization of acrylates under air.

Domaines: Chimie organique

Sofia Telitel, Anne-Laure Vallet, Stéphane Schweizer, Bernard Delpech, Nicolas Blanchard, et al.. Formation of N-heterocyclic carbene-boryl radicals through electrochemical and photochemical cleavage of the B-S bond in N-heterocyclic carbene-boryl sulfides.. Journal of the American Chemical Society, 2013, 135 (45), pp.16938-47. ⟨10.1021/ja4066267⟩. ⟨hal-00933829⟩