Light-driven reduction of aromatic olefins in aqueous media catalysed by aminopyridine cobalt complexes

Abstract

A catalytic system based on earth-abundant elements that efficiently hydrogenates aryl olefins using visible light as driving-force and H2O as the sole hydrogen atom source is reported. The catalytic system...

Photo‐ and Electrochemical Cobalt Catalysed Hydrogen Atom Transfer for the Hydrofunctionalisation of Alkenes

“…[76] Notably, this method contrasts with the report by Lin and co-workers (section 3.4) which generally prefers electron rich olefins. [52] Inspired by the deuterium atom transfer (DAT) deuteration of alkenes by Lloret-Fillol et al, which uses D 2 O, [77] the authors have demonstrated the use of ascorbic acid-d 4 as a cheap and easily available source of deuterium. This can be obtained on a gram scale by mixing ascorbic acid and D 2 O in acetonitrile followed by successive removal of volatile components.…”

Photocatalytic Transfer Hydrogenation Reactions Using Water as the Proton Source

“…Alternatively, a direct nucleophilic attack of a putative [Co II –H] species may be also considered (heterolytic pathway, Scheme b, right). By similar methods, their group has proposed that the reduction of aromatic olefins in their reaction system takes place by a HAT mechanism, most likely via [Co–H] intermediates …”

“…By similar methods, their group has proposed that the reduction of aromatic olefins in their reaction system takes place by a HAT mechanism, most likely via [Co−H] intermediates. 42 2.2. From Nanoparticle to Single-Atom Catalysts.…”

Photocatalytic Deuterium Atom Transfer Deuteration of Electron‐Deficient Alkenes with High Functional Group Tolerance

“…An insightful alternative strategy for DAT deuteration, published by Lloret-Fillol and coworkers, showed that the DAT deuteration of alkenes could be accomplished using a [Cu(bathocuproine)(xantphos)] + complex as a photoredox catalyst, a [Co(OTf)(Py 2 Ts tacn)] + (Py 2 Ts tacn = 1,4-di(picolyl)-7-(p-toluenesulfonyl)-1,4,7-triazacyclononane) complex as a cocatalyst, and D 2 O as a readily accessible deuterium source (Scheme 1c). [11] However, the scope of this DAT deuteration is limited to terminal vinylarenes. In addition, modest functional group tolerance including partial dehalogenation of a bromoarene observed under their typical reaction conditions stands as a challenge for widespread synthetic applications of this DAT deuteration.…”

“…However, the chemistry has not been expanded to preparative DAT deuteration due to the limited accessibility of deuterated organosilanes. An insightful alternative strategy for DAT deuteration, published by Lloret‐Fillol and co‐workers, showed that the DAT deuteration of alkenes could be accomplished using a [Cu(bathocuproine)(xantphos)] + complex as a photoredox catalyst, a [Co(OTf)(Py 2 Ts tacn)] + (Py 2 Ts tacn=1,4‐di(picolyl)‐7‐( p ‐toluenesulfonyl)‐1,4,7‐triazacyclononane) complex as a cocatalyst, and D 2 O as a readily accessible deuterium source (Scheme 1c) [11] . However, the scope of this DAT deuteration is limited to terminal vinylarenes.…”