An unprecedented dioxygen-triggered oxidative radical process was explored using dioxygen as the solely terminal oxidant, realizing aerobic oxidaitve difunctionalization of alkynes toward β-keto sulfones with high selectivity. Operando IR experiments revealed that pyridine not only acts a base to successfully surpress ATRA (atom transfer addition) process, but also plays vital role in reducing activity sulfinic acids.

Attraktive Variante: Eine neuartige Disauerstoff-Aktivierung durch Sulfinsäuren führt ohne Zusatz von Übergangsmetallverbindungen oder Radikalinitiatoren unter milden Bedingungen zu sekundären und tertiären β-Hydroxysulfonen. β-Hydroperoxysulfon wurde als eine wichtige Zwischenstufe isoliert.

Abstract A strategy is reported in which traceless directing groups (TDGs) are used to promote the redox‐neutral Mn I ‐catalyzed regioselective synthesis of N‐heterocycles. Alkyne coupling partners bearing a group, serves as both chelator and internal oxidant, were control regioselectivity annulation reactions. This operationally simple approach highly effective with previously challenging unsymmetrical alkyne systems, including unbiased dialkyl alkynes, perfect regioselectivity. The...

Abstract A Mn I ‐catalyzed regioselective C−H allenylation is reported that allows a broad range of 2‐allenylindoles to be synthesized regioselectively on gram scale under simple conditions. Notably, highly efficient chirality transfer was observed (up 93 % ee ) in this transformation. This procedure further found allow, for the first time, direct preparation ketones by activation. Mechanistic investigations revealed precoordination oxygen atom manganese center as well congested tertiary...

Due to the intrinsic inertness of alkanes, strong oxidative conditions are typically required enable their C(sp3 )-H functionalization. Herein, a paired electrocatalysis strategy was developed by integrating catalysis with reductive in one cell without interference, which earth-abundant iron and nickel employed as anodic cathodic catalysts, respectively. This approach lowers previously high oxidation potential for alkane activation, enabling electrochemical functionalization at ultra-low...

Manganese-catalyzed sequential C–H and C–C/C–Het bond activation to synthesize allylic alcohols, allylated arenes, functionalized cyclopentenes skipped dienes is reported.

Abstract Controlling selectivity is of central importance to radical chemistry. However, the highly reactive and unstable intermediates make this task especially challenging. Herein, a strategy for taming redox reactions has been developed, in which solvent‐bonding can alter reactivity generated thereby drastically reaction at room temperature. Various β‐oxy sulfoxides β‐hydroxy sulfides be facilely obtained, some are difficult synthesize by existing methods. Notably, neither metal catalyst...

Achieving controllable C–H functionalization to elaborate valuable compounds from simple chemicals is attractive and highly desirable, especially if nonprecious transition metal catalysts can be used. However, controlling selectivity in these transformations remains a continuous challenge synthetic chemists. Herein, we show for the first time that control over reactive organometallic intermediate enables switchable synthesis of quinoline indole amides alkynes through activation using...

Abstract Direct radical additions to terminal alkynes have been widely employed in organic synthesis, providing credible access the anti‐Markovnikov products. Because of Kharasch effect, regioselective control for formation Markovnikov products still remains a great challenge. Herein, we develop transition‐metal‐free, visible light‐mediated addition S‐nucleophiles alkynes, furnishing wide array α‐substituted vinyl sulfones with exclusive regioselectivity. Mechanistic investigations...

A new radical oxytrifluoromethylation of alkenes via an aerobic Cvinyl-heteroatom bond oxygenation process is reported, in which O2 and a catalytic amount K2S2O8 work concert to activate CF3SO2Na. Mechanistic investigation disclosed that CF3SO2˙ could react with reinitiate chain process.

Herein, a fast, scalable, and transition-metal-free borylation of alkyl halides (X = I, Br, Cl) enabled by electroreduction is reported. This process provides an efficient practical access to primary, secondary, tertiary boronic esters at high current. More than 70 examples, including the late-stage natural products drug derivatives, are furnished room temperature, thereby demonstrating broad utility functional-group tolerance this protocol. Mechanistic studies disclosed that B2cat2 serves...

An unprecedented MnI -catalyzed (2-indolyl)methylation of heteroarenes is reported. This method makes use an aromatizing cascade strategy to install a (2-indolyl)methyl group into target molecules, thereby leading the expedient synthesis previously challenging and important unsymmetrical diheteroarylmethanes, in particular bis(2-indolyl)methanes. The proposed process comprises reorganization multiple bonds with controlled regioselectivity high atom economy can be performed on gram-scale....

Radical style: Several breakthroughs have recently been achieved in enantioselective C(sp3)−H functionalization through radical activation. These new strategies show how chemistry can be used to convert alkanes into functionalized chiral molecules (see scheme; HAT=hydrogen atom transfer).

Selective hydrogenation of epoxides would be a direct and powerful approach for alcohol synthesis, but it has proven to elusive. Here, electrochemically epoxide using electrons protons as reductants is reported. A wide range primary, secondary, tertiary alcohols can achieved through selective Markovnikov or anti-Markovnikov ring opening in the absence transition metals. Mechanistic investigations revealed that regioselectivity controlled by thermodynamic stabilities situ generated benzyl...

This report describes the unprecedented electrooxidation of a solvent (e.g., DMF)-ligated B2 cat2 complex, whereby solvent-stabilized boryl radical is formed via quasi-homolytic cleavage B-B bond in DMF-ligated cation. Cyclic voltammetry and density functional theory provide evidence to support this novel activation strategy. Furthermore, strategy for electrochemical gem-diborylation gem-bromides paired electrolysis developed first time, affording range versatile gem-diborylalkanes, which...

We report a combination of electrocatalysis and photoredox catalysis to perform selective C(sp3)-H arylation/alkylation alkanes, in which binary catalytic system based on earth-abundant iron nickel is applied. Reaction selectivity between two-component arylation three-component alkylation tuned by modulating the applied current light source. Importantly, an ultra-low anodic potential (~0.23 V vs. Ag/AgCl) this protocol, thus enabling compatibility with variety functional groups (>70...

Direct functionalization of inert C-H bonds is one the most attractive yet challenging strategies for constructing molecules in organic chemistry. Herein, we disclose an unprecedented and Earth abundant Cu/Cr catalytic system which unreactive alkyl are transformed into nucleophilic alkyl-Cr(III) species at room temperature, enabling carbonyl addition reactions with strong bonds. Various aryl alcohols furnished under mild reaction conditions even on a gram scale. Moreover, this new...

Asymmetric electrocatalysis offers exciting new strategies for the synthesis of chiral molecules through novel reaction pathways. However, simultaneous activation reactants on both electrodes via asymmetric paired electrolysis, which is more energy efficient and economic than single half-electrode synthesis, remains a formidable challenge. Herein, an olefin–sulfonylimine coupling presented first time. In this protocol, Co-catalyzed hydrogen atom transfer anode Ni-catalyzed sulfonylimine...

Abstract The simultaneous activation of reactants on the anode and cathode via paired electrocatalysis has not been extensively demonstrated. This report presents a oxidative reductive catalysis based earth-abundant iron/nickel cocatalyzed C–C functionalization ubiquitous alcohols. A variety alcohols (i.e., primary, secondary, tertiary, or unstrained cyclic alcohols) can be activated at very low oxidation potential (~0.30 V vs. Ag/AgCl) photoelectrocatalysis coupled with versatile...

A novel strategy was developed to trigger ·CF3 by using in situ generated peroxide NMP under O2 or air as the radical initiator. Radical trifluoromethylation of alkenes achieved toward tertiary β-trifluoromethyl alcohols. Various alcohols can be synthesized good yields without extra oxidants transition metal catalysts. Preliminary mechanistic investigation revealed that diffusion influence reaction rate.

An unprecedented single electron redox process in copper catalysis is confirmed using operando X-ray absorption and EPR spectroscopies. The oxidation state of the species interaction between Cu(II) a sulfinic acid at room temperature, accurate characterization formed Cu(I) are clearly shown evidence. Further investigation anion effects on discloses that bromine ions can dramatically increase rate process. Moreover, it proven acids converted into sulfonyl radicals, which be trapped by...

The dioxygen-induced radical oxyphosphorylation of alkenes and alkynes is presented, wherein a P–H bond was activated by molecular oxygen.

Abstract Eine regioselektive und durch Mangan(I)‐katalysierte C‐H‐Allenierung wird beschrieben. Diese ermöglicht einen einfachen Zugang zu einer Reihe von 2‐Allenylindolen, auch im Grammmaßstab. Durch Chiralitätstransfer können bis 93 % ee erreicht werden. Mit leicht modifizierten Reaktionsbedingungen außerdem zum ersten Mal Ketone direkt über C‐H‐Aktivierung hergestellt Mechanistische Untersuchungen unterstreichen die große Bedeutung der Koordination des Carbonat‐Sauerstoffatoms an den...

A highly selective radical dioxygenation of alkenes using hydroxamic acid and O2 was developed, copper/cobalt used as the catalyst without assistance any additional ligands or bases. Mechanistic investigation disclosed that copper salt work in concert to activate acid, with Cu(I) Cu(II) concurrently existing this reaction.