Photoredox catalysis is emerging as a powerful tool in synthetic organic chemistry. The aim of this synopsis to provide an overview the photoelectronic properties photoredox catalysts they are applied transformations. In addition, recent applications presented.

Herein, the development of visible light-mediated atom transfer radical addition (ATRA) haloalkanes onto alkenes and alkynes using reductive oxidative quenching [Ir{dF(CF(3))ppy}(2)(dtbbpy)]PF(6) [Ru(bpy)(3)]Cl(2) is presented. Initial investigations indicated that photocatalysts could effectively be utilized for ATRA, since report, protocol has been expanded by broadening scope reaction in terms photocatalysts, substrates, solvents. In addition, further modifications conditions allowed...

We report an operationally simple, tin-free reductive dehalogenation system utilizing the well-known visible-light-activated photoredox catalyst Ru(bpy)3Cl2 in combination with iPr2NEt and HCO2H or Hantzsch ester as hydrogen atom donor. Activated C−X bonds may be reduced good yields excellent functional-group tolerance chemoselectivity over aryl vinyl bonds. The proposed mechanism involves visible-light excitation of catalyst, which is by 3° amine to produce single-electron reducing agent...

We report the application of visible-light photoredox catalysis for formation C-C bonds between tertiary N-arylamines and nitroalkanes via an oxidative aza-Henry reaction. In presence 1 mol % Ir(ppy)(2)(dtbbpy)PF(6), efficient coupling with in situ-generated iminium ions provides desired products up to 96% yield. Mechanistic studies suggest that reductive quenching Ir(3+) excited state by amine leads ammonium radical cation, subsequent catalyst turnover (Ir(2+) --> Ir(3+)) likely effected...

Atom transfer radical addition of haloalkanes and α-halocarbonyls to olefins is efficiently performed with the photocatalyst Ir[(dF(CF3)ppy)2(dtbbpy)]PF6. This protocol characterized by excellent yields, mild conditions, low catalyst loading, broad scope. In addition, atom can be used quickly introduce vinyl trifluoromethyl groups access 1,1-cyclopropane diesters.

While the use of visible light to drive chemical reactivity is high importance development environmentally benign transformations, concomitant a stoichiometric electron donor or acceptor often required steer desired redox behavior these systems. The low-cost and ubiquity tertiary amine bases has led their widespread as reductive additives in photoredox catalysis. Early trialkylamines this context was focused on role excited state quenchers photocatalyst, which turn provides more highly...

ConspectusHarnessing visible light as the driving force for chemical transformations generally offers a more environmentally friendly alternative compared with classical synthetic methodology. The transition metal-based photocatalysts commonly employed in photoredox catalysis absorb efficiently spectrum, unlike most organic substrates, allowing orthogonal excitation. subsequent excited states are both reducing and oxidizing than ground state catalyst competitive some of powerful...

The development of a room-temperature lignin degradation strategy consisting chemoselective benzylic oxidation with recyclable oxidant ([4-AcNH-TEMPO]BF4) and catalytic reductive C–O bond cleavage utilizing the photocatalyst [Ir(ppy)2(dtbbpy)]PF6 is described. This system was tested on relevant model substrates containing β-O-4 linkages to generate fragmentation products in good excellent yields.

Abstract The large number of reagents that have been developed for the synthesis trifluoromethylated compounds is a testament to importance CF 3 group as well associated synthetic challenge. Current state-of-the-art appending functionality directly are highly effective; however, their use on preparative scale has minimal precedent because they require multistep preparation, and/or prohibitively expensive large-scale application. For scalable trifluoromethylation methodology, trifluoroacetic...

Our previous studies into visible-light-mediated aza-Henry reactions demonstrated that molecular oxygen played a vital role in catalyst turnover as well the production of base to facilitate nucleophilic addition nitroalkanes. Herein, improved conditions for generation iminium ions from tetrahydroisoquinolines allow versatile trapping are reported. The new provide access diverse range functionality under mild, anaerobic reaction mechanistic insights photoredox cycle.

The photoredox-mediated direct intermolecular C−H functionalization of substituted indoles, pyrroles, and furans with diethyl bromomalonate is described, utilizing the visible light-induced reductive quenching pathway Ru(bpy)3Cl2. An analysis quenchers mechanistic considerations has led to an optimized protocol for heteroaromatic alkylations, providing products in good yields regioselectivities, as well successfully eliminating previously observed competitive side reactions. This methodology...

Photoredox catalysis: A variety of organic transformations mediated by visible-light-active photoredox catalysts have been conducted in a photochemical flow reactor. The reactor design is very simple and can be easily implemented any laboratory (see picture). In addition, this afforded marked increase the reaction rate compared to those observed typical batch (round bottom flask) reactors.

Photoredox catalysis has emerged as a powerful tool for the synthetic chemist to access challenging targets and generate new structural complexity. This review focuses on application of this mode arrive at known pharmaceutically active compounds. Within setting, growing synergy with other modes catalysis, such nickel/photoredox dual well pioneering examples utilizing continuous flow transition photoredox preparative scale will be highlighted.

The utilization of the photoredox catalyst, tris(2,2'-bipyridyl)ruthenium dichloride, and a household light bulb to effect radical cyclizations onto indoles pyrroles at room temperature is reported. A reactive free intermediate generated via reduction an activated C-Br bond by single electron reductant, Ru(I), in visible induced photocatalytic cycle. This system represents expansion application catalysis conventional processes.

Alkene aminoarylation with a single, bifunctional reagent is concise synthetic strategy. We report catalytic protocol for the addition of arylsulfonylacetamides across electron-rich alkenes complete anti-Markovnikov regioselectivity and excellent diastereoselectivity to provide 2,2-diarylethylamines. In this process, single-electron alkene oxidation enables carbon-nitrogen bond formation key benzylic radical poised Smiles-Truce 1,5-aryl shift. This reaction redox-neutral, exhibits broad...

Lignin is a recalcitrant and underexploited natural feedstock for aromatic commodity chemicals, its degradation generally requires the use of high temperatures harsh reaction conditions. Herein we present an ambient temperature one-pot process controlled oxidation depolymerization this potent resource. Harnessing potential electrocatalytic in conjugation with our photocatalytic cleavage methodology, have developed operationally simple procedure selective fragmentation β-O-4 bonds excellent...

The enantioselective oxidative C-H functionalization of tetrahydroisoquinoline derivatives is achieved through the merger photoredox and asymmetric anion-binding catalysis. This combination two distinct catalysis concepts introduces a potentially general approach to transformations in photocatalysis.

Lighting the way: In a 10-step total synthesis of title compound, visible-light photoredox catalysis enabled construction key bond by facilitating direct coupling pyrroloindoline-derived radical with substituted indole (see scheme; Boc=tert-butyloxycarbonyl, Cbz=benzyloxycarbonyl, DMF=N,N′-dimethylformamide). This represents first implementation in synthesis.