Carbon−Fluorine Reductive Elimination from a High-Valent Palladium Fluoride

Carbon−Fluorine Reductive Elimination from a High-Valent Palladium Fluorid

A Perspective on Late-Stage Aromatic C–H Bond Functionalization

Late-stage functionalization of C–H bonds (C–H LSF) can provide a straightforward approach to the efficient synthesis of functionalized complex molecules. However, C–H LSF is challenging because the C–H bond must be functionalized in the presence of various other functional groups. In this Perspective, we evaluate aromatic C–H LSF on the basis of four criteriareactivity, chemo­selectivity, site-selectivity, and substrate scopeand provide our own views on current challenges as well as promising strategies and areas of growth going forward

Carbon−Fluorine Reductive Elimination from a High-Valent Palladium Fluoride

Carbon−Fluorine Reductive Elimination from a High-Valent Palladium Fluorid

Fluorination of Boronic Acids Mediated by Silver(I) Triflate

A regiospecific Ag-mediated fluorination reaction of aryl- and alkenylboronic acids and esters is reported. The fluorination reaction uses commercially available reagents, does not require the addition of exogenous ligands, and can be performed on a multigram scale. This report discloses the first practical reaction sequence from arylboronic acid to aryl fluorides

PhenoFluorMix: Practical Chemoselective Deoxyfluorination of Phenols

A practical deoxyfluorination with novel deoxyfluorinating reagent PhenoFluorMix, a mixture of <i>N,N</i>′-1,3-bis­(2,6-diisopropylphenyl)­chloroimidazolium chloride and CsF, is presented. PhenoFluorMix overcomes the challenges associated with hydrolysis of PhenoFluor. PhenoFluorMix does not hydrolyze, is readily available on decagram scale, and is storable in air. In this paper, we demonstrate the practicality of the reagent and exhibit the deoxyfluorination of a variety of phenols and heterocycles

A Transition State Analogue for the Oxidation of Binuclear Palladium(II) to Binuclear Palladium(III) Complexes

Cooperative metal–metal (M–M) redox chemistry has the potential to lower activation barriers for redox transformations relevant to catalysis. Pd2(III,III) complexes, generated by oxidation of Pd2(II,II) complexes, have recently been implicated as intermediates in a variety of Pd-catalyzed C–H oxidation reactions. M–M redox synergy, mediated by Pd–Pd bond formation and cleavage, has been proposed to facilitate both oxidation and reductive elimination steps during various Pd-catalyzed directed C–H oxidation reactions. Herein, we report a transition state mimic for the oxidation of Pd2(II,II) complexes which suggests that M–M redox synergy is involved in the oxidation of Pd2(II,II) complexes to Pd2(III,III) complexes

A Transition State Analogue for the Oxidation of Binuclear Palladium(II) to Binuclear Palladium(III) Complexes

Cooperative metal–metal (M–M) redox chemistry has the potential to lower activation barriers for redox transformations relevant to catalysis. Pd₂(III,III) complexes, generated by oxidation of Pd₂(II,II) complexes, have recently been implicated as intermediates in a variety of Pd-catalyzed C–H oxidation reactions. M–M redox synergy, mediated by Pd–Pd bond formation and cleavage, has been proposed to facilitate both oxidation and reductive elimination steps during various Pd-catalyzed directed C–H oxidation reactions. Herein, we report a transition state mimic for the oxidation of Pd₂(II,II) complexes which suggests that M–M redox synergy is involved in the oxidation of Pd₂(II,II) complexes to Pd₂(III,III) complexes

Synthesis of Benzylic Alcohols by C–H Oxidation

Selective methylene C–H oxidation for the synthesis of alcohols with a broad scope and functional group tolerance is challenging due to the high proclivity for further oxidation of alcohols to ketones. Here, we report the selective synthesis of benzylic alcohols employing bis­(methanesulfonyl) peroxide as an oxidant. We attempt to provide a rationale for the selectivity for monooxygenation, which is distinct from previous work; a proton-coupled electron transfer mechanism (PCET) may account for the difference in reactivity. We envision that our method will be useful for applications in the discovery of drugs and agrochemicals

Deoxyfluorination of Phenols

An operationally simple ipso fluorination of phenols with a new deoxyfluorination reagent is presented

Synthesis of Benzylic Alcohols by C–H Oxidation

Selective methylene C–H oxidation for the synthesis of alcohols with a broad scope and functional group tolerance is challenging due to the high proclivity for further oxidation of alcohols to ketones. Here, we report the selective synthesis of benzylic alcohols employing bis­(methanesulfonyl) peroxide as an oxidant. We attempt to provide a rationale for the selectivity for monooxygenation, which is distinct from previous work; a proton-coupled electron transfer mechanism (PCET) may account for the difference in reactivity. We envision that our method will be useful for applications in the discovery of drugs and agrochemicals