Stereodivergent Alkyne Hydrofluorination Using Protic Tetrafluoroborates as Tunable Reagents

Guo, Rui; Qi, Xiaotian; Xiang, Hengye; Geaneotes, Paul; Wang, Ruihan; Liu, Peng; Wang, Yiming

doi:10.1002/ange.202006278

Cited by 7 publications

(1 citation statement)

References 73 publications

(1 reference statement)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our approach requires BF3-OEt2 to act as a catalyst for both defluorination and fluorination events in a single catalytic sequence. Lewis acidic group 13 compounds have been reported as both reagents and catalysts for the hydrofluorination of internal alkynes [17][18][19] and the defluorination of fluoroalkanes, [20][21][22] and represented a logical starting point for the development of an HF shuttle catalyst. Very recently, BF3-OEt2 has been reported as a catalyst for the homologation of fluoroalkanes with diazoesters, 23 and the intramolecular fluorocarbamoylation of alkynes.…”

mentioning

confidence: 99%

Catalytic HF Shuttling between Fluoroalkanes and Alkynes

Mulryan

Rekhroukh

Farley

et al. 2023

Preprint

View full text Add to dashboard Cite

In this paper we report a catalytic method to transfer formal equivalents of HF from fluoroalkanes to an alkyne. The method leads to a simple and sustainable approach to generate difluoroalkanes and tolerates numerous sensitive functional groups including halogen, protected amine, ester and thiophene substituents. BF3-OEt2 catalyses this new catalytic transformation. Mechanistic studies (DFT, probe experiments) suggest the catalyst is intimately involved in both the defluorination and fluorination steps required for HF transfer, with BF3 acting as a Lewis acid and OEt2 a weak Lewis base that mediates proton transfer. Fluoroalkenes are demonstrated as competent intermediates and their conversion to difluoroalkanes was found to be reversible. These results establish the first true HF shuttle process (i.e. bidirectional) and represent a potentially powerful method for recycling fluorocarbons

show abstract

mentioning

confidence: 99%

Catalytic HF Shuttling between Fluoroalkanes and Alkynes

Mulryan

Rekhroukh

Farley

et al. 2023

Preprint

View full text Add to dashboard Cite

show abstract

Recent Advances in the Functionalization of Terminal and Internal Alkynes

et al. 2022

View full text Add to dashboard Cite

Alkynes are one of the most fundamental and diverse functional groups utilized in organic synthesis. Over the past few years, the development of efficient synthetic methodologies for the functionalization of alkynes has been an active area of research. A plethora of alkyne functionalization reactions have been reported in the literature to construct functionalized alkynes and alkene scaffolds, which are important building blocks in many natural products, pharmaceuticals, and key intermediates in various synthetic transformations. In this review, we describe the most recent advances in the functionalization of alkynes with an emphasis on substrate scope, limitations, regioselectivity control and applications of these reactions. This review covers the literature from 2016 to 2021.

show abstract

Platin‐katalysierte Hydrofluorierung von Alkinen: Steuerung der Reaktivität von Fluoridionen durch Wasserstoffbrückenbindungen zu Indolylphosphan‐Liganden

Sander

Braun

2022

Angewandte Chemie

View full text Add to dashboard Cite

Die Reaktion der Platin‐Komplexe cis‐[Pt(CH3)2{R2P(Ind)}2] (Ind=2‐(3‐methyl)indolyl, R=Ph (1 a), 4‐FC6H4 (1 b), 4‐CF3C6H4 (1 c)) mit HF führte zur Bildung der Poly(hydrogenfluorid)fluorido‐Komplexe trans‐[Pt(F(HF)2)(CH3){R2P(Ind)}2] 2 a–c, welche durch Umsetzung mit CsF in die HF freien Komplexe trans‐[Pt(F)(CH3){R2P(Ind)}2] (3 a–c) überführt werden können. Durch Zugabe von 3‐Hexin zu 2 a–c bildeten sich die Alkin‐Komplexe trans‐[Pt(C,C‐η2‐C2H5C≡CC2H5)(CH3){R2P(Ind)}2{F(HF)2}] (4 a–c), bei denen der Fluorido‐Ligand nunmehr als ein F(HF)2−‐Ion vorliegt, welches durch Wasserstoffbrückenbindungen zu den Indolylphosphan‐Liganden in der äußeren Koordinationssphäre stabilisiert wird. Beim Erhitzen einer Reaktionslösung von 4 a in Anwesenheit von PVPHF erfolgte die Bildung des (Z)‐Fluoralkens aus dem metallgebundenen Alkin. Hierauf aufbauend wurden katalytische Hydrofluorierungsreaktionen zur selektiven Darstellung von (Z)‐Fluoralkenen aus Alkinen entwickelt. Es zeigte sich, dass die in der äußeren Koordinationssphäre vorhandenen Wasserstoffbrückenbindungen zum F(HF)2−‐Ion den Fluorierungsschritt begünstigen. Dies konnte durch Reaktivitätsstudien mit Komplexen ohne Indolylgruppen am Phosphan‐Liganden untermauert werden.

show abstract

Stereodivergent Alkyne Hydrofluorination Using Protic Tetrafluoroborates as Tunable Reagents

Cited by 7 publications

References 73 publications

Catalytic HF Shuttling between Fluoroalkanes and Alkynes

Catalytic HF Shuttling between Fluoroalkanes and Alkynes

Recent Advances in the Functionalization of Terminal and Internal Alkynes

Platin‐katalysierte Hydrofluorierung von Alkinen: Steuerung der Reaktivität von Fluoridionen durch Wasserstoffbrückenbindungen zu Indolylphosphan‐Liganden

Contact Info

Product

Resources

About