Cargando…

An organophotocatalytic late-stage N–CH(3) oxidation of trialkylamines to N-formamides with O(2) in continuous flow

We report an organophotocatalytic, N–CH(3)-selective oxidation of trialkylamines in continuous flow. Based on the 9,10-dicyanoanthracene (DCA) core, a new catalyst (DCAS) was designed with solubilizing groups for flow processing. This allowed O(2) to be harnessed as a sustainable oxidant for late-st...

Descripción completa

Detalles Bibliográficos
Autores principales: Mandigma, Mark John P., Žurauskas, Jonas, MacGregor, Callum I., Edwards, Lee J., Shahin, Ahmed, d'Heureuse, Ludwig, Yip, Philip, Birch, David J. S., Gruber, Thomas, Heilmann, Jörg, John, Matthew P., Barham, Joshua P.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: The Royal Society of Chemistry 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8849051/
https://www.ncbi.nlm.nih.gov/pubmed/35308839
http://dx.doi.org/10.1039/d1sc05840a
Descripción
Sumario:We report an organophotocatalytic, N–CH(3)-selective oxidation of trialkylamines in continuous flow. Based on the 9,10-dicyanoanthracene (DCA) core, a new catalyst (DCAS) was designed with solubilizing groups for flow processing. This allowed O(2) to be harnessed as a sustainable oxidant for late-stage photocatalytic N–CH(3) oxidations of complex natural products and active pharmaceutical ingredients bearing functional groups not tolerated by previous methods. The organophotocatalytic gas–liquid flow process affords cleaner reactions than in batch mode, in short residence times of 13.5 min and productivities of up to 0.65 g per day. Spectroscopic and computational mechanistic studies showed that catalyst derivatization not only enhanced solubility of the new catalyst compared to poorly-soluble DCA, but profoundly diverted the photocatalytic mechanism from singlet electron transfer (SET) reductive quenching with amines toward energy transfer (E(n)T) with O(2).