Exploiting photoredox catalysis for the synthesis of tetra- and di-hydrofurans

Expanding the Scope of Photocatalysis: Atom Transfer Radical Addition of Bromoacetonitrile to Aliphatic Olefins

“…If no sodium ascorbate was employed, no product could be identified (entry ). This is in complete agreement with the literature in that aliphatic olefins do not lead to product formation if sodium ascorbate is absent . Moreover, if the reaction was kept in the dark, 1‐decene did not convert to the corresponding product (entry ).…”

“…A very recent photoorganocatalytic example, demonstrating a single example with bromoacetonitrile was also reported by Cozzi and co‐workers . Also, two methods were developed for the addition of bromoacetonitrile to styrene derivatives under photoredox catalysis (Scheme C) . In both instances, the olefin was only limited to styrene derivatives and the intermediate radical was trapped by the alcoholic solvent, evidence that this method proceeds via a carbocation intermediate and that the more versatile bromide intermediates could not be isolated.…”

Light on Unsaturated Hydrocarbons – “Gotta Heterofunctionalize Them All”

“…Greaney and coworkers further investigated this carbooxycyclization and engaged a pendant alcohol linked to the bromoester unit (Scheme 55, Part A). [63] Both electron-donating (288) and -withdrawing (289) arylsubstituted styrenes were tolerated. Notably, ortho substitution was compatible with the methodology.…”

“…In parallel, the Greaney group developed a similar methodology involving Zn(OAc) 2 as an additive (Scheme 48). [63] Scheme 48. Method for γ-alkoxynitrile synthesis reported by Greaney.…”

Photocatalytic Atom Transfer Radical Addition to Olefins Utilizing Novel Photocatalysts

“…Brominated compounds are valuable scaffolds in organic synthesis, being able to undergo further transformation into useful functional groups. A well-known brominating reagent for ATRA reactions is bromoacetonitrile, which has been widely used, by different research groups, making it a well-established precursor of addition products [22,23,24,25]. However, the scope of olefins employed in ATRA reactions with bromoacetonitrile, in the presence of a metal-based catalyst, is rather limited (Scheme 1A).…”