Synthetic Advantages of Defluorinative C−F Bond Functionalization

Hooker, Leidy V.; Bandar, Jeffrey S.

doi:10.1002/anie.202308880

Cited by 37 publications

(10 citation statements)

References 309 publications

(342 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Key reactions in which main-group systems have been studied are catalytic hydrodefluorination (HDF) and related defluorination processes (Scheme ). These are important approaches to prepare complex fluorinated molecules, which have applications in pharmaceuticals, , agrochemicals, and materials chemistry, from readily available polyfluorinated precursors . Transition-metal-based C–F functionalization is relatively well established, − and a range of main-group systems have also been explored for HDF. , These include non-redox systems such as strong Lewis acids, including electron-deficient phosphonium ions, − and FLPs, which allow HDF of aliphatic C–F bonds, tetrabutylammonium triphenyldifluorosilicate (TBAT), NaBH 4 , and diazaphospholenes, , which can catalyze HDF of aromatic C–F bonds and trifluoromethylalkenes.…”

Section: Introductionmentioning

confidence: 99%

Metallomimetic C–F Activation Catalysis by Simple Phosphines

Bonfante,

Lorber,

Lynam

et al. 2024

J. Am. Chem. Soc.

View full text Add to dashboard Cite

Delivering metallomimetic reactivity from simple pblock compounds is highly desirable in the search to replace expensive, scarce precious metals by cheap and abundant elements in catalysis. This contribution demonstrates that metallomimetic catalysis, involving facile redox cycling between the P(III) and P(V) oxidation states, is possible using only simple, cheap, and readily available trialkylphosphines without the need to enforce unusual geometries at phosphorus or use external oxidizing/reducing agents. Hydrodefluorination and aminodefluorination of a range of fluoroarenes was realized with good to very good yields under mild conditions. Experimental and computational mechanistic studies show that the phosphines undergo oxidative addition of the fluoroaromatic substrate via a Meisenheimer-like transition state to form a fluorophosphorane. This undergoes a pseudotransmetalation step with a silane, via initial fluoride transfer from P to Si, to give experimentally observed phosphonium ions. Hydride transfer from a hydridosilicate counterion then leads to a hydridophosphorane, which undergoes reductive elimination of the product to reform the phosphine catalyst. This behavior is analogous to many classical transition-metal-catalyzed reactions and so is a rare example of both functional and mechanistically metallomimetic behavior in catalysis by a main-group element system. Crucially, the reagents used are cheap, readily available commercially, and easy to handle, making these reactions a realistic prospect in a wide range of academic and industrial settings.

show abstract

Section: Introductionmentioning

confidence: 99%

Metallomimetic C–F Activation Catalysis by Simple Phosphines

Bonfante,

Lorber,

Lynam

et al. 2024

J. Am. Chem. Soc.

View full text Add to dashboard Cite

show abstract

“…For step- and atom-economical strategies, methods for direct C–H and C–F functionalization of (poly)fluoroarenes have considerable advantages over traditional methods that require more steps to produce preactivated reagents and make this approach “greener”. There are several reviews which concern access to fluorinated organic molecules via transition-metal-catalyzed C–F bond functionalization reactions. , − This review summarizes the applications of transition-metal-catalyzed C–H bond activation, specifically at positions ortho to fluorine, for the synthesis of functionalized fluoroarenes. As such, it complements our earlier review, which focused on the competition between C–F and C–H activation via interaction of fluorinated arenes with transition metal complexes.…”

Section: Introductionmentioning

confidence: 99%

Applications of Transition Metal-Catalyzed ortho-Fluorine-Directed C–H Functionalization of (Poly)fluoroarenes in Organic Synthesis

Budiman,

Perutz,

Steel

et al. 2024

Chem. Rev.

View full text Add to dashboard Cite

The synthesis of organic compounds efficiently via fewer steps but in higher yields is desirable as this reduces energy and reagent use, waste production, and thus environmental impact as well as cost. The reactivity of C−H bonds ortho to fluorine substituents in (poly)fluoroarenes with metal centers is enhanced relative to meta and para positions. Thus, direct C−H functionalization of (poly)fluoroarenes without prefunctionalization is becoming a significant area of research in organic chemistry. Novel and selective methodologies to functionalize (poly)fluorinated arenes by taking advantage of the reactivity of C−H bonds ortho to C−F bonds are continuously being developed. This review summarizes the reasons for the enhanced reactivity and the consequent developments in the synthesis of valuable (poly)fluoroarene-containing organic compounds.

show abstract

“…9 Because of the increasing significance of C–F bond formation and ready availability of many fluorine-substituted aryl motifs, the functionalization of aryl C–F bonds has garnered escalating attention. 10 However, unlike other C–X bonds, relatively limited success has been achieved in the borylation of C–F bonds in fluoroarenes since the C–F bond is known as one of the strongest bonds in organic compounds. Martin and Radius independently disclosed the borylation of fluoroarenes by the cleavage of C–F bonds with nickel catalysis using B 2 nep 2 or B 2 pin 2 as a boron source (Scheme 1a).…”

mentioning

confidence: 99%