Rhodium(I)-Catalyzed Defluorinative Coupling of Boronic Acids with Monofluoroalkenes

Abstract

We herein describe a highly selective Rh­(I)-catalyzed defluorinative coupling of boronic acids with (E)-β-monofluoroacrylates. In contrast to previous methods, the trisubstituted (Z)-alkene products were obtained in excellent dr with an inversion of double bond geometry. Experimental and computational studies established that Rh­(I)-facilitated β-F elimination is favored over competing β-H elimination and protodemetalation.

Exploring α-electron-deficiency-induced [1,2]-fluorine migration

“…5a shows the results of different nucleophile reactions with reported acyl fluorides (3-8) and Fig. 5b shows the results of benzene anion reaction with different acyl fluoride substrates (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). It all means that no matter the kind of nucleophile or acyl fluoride substrate, the above linear relationship is followed in all cases.…”

“…This section will present an investigation of [1,2]-fluorine migration reactions involving α,β-unsaturated acyl fluoride substrates when a nucleophile is present. The α,β-unsaturated acyl fluoride substrates (3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20) used in this study are shown in Scheme 2. Typically, these substrates are prepared by reacting the corresponding α,β-unsaturated acyl chlorides with silver difluoride.…”

“…1 Organic fluoride compounds exhibit unique physical and chemical stability and properties, and some research has confirmed their suitability for a range of applications, [2][3][4][5][6] including refrigerants, flame retardants, chemical sensors, pesticides, pharmaceuticals, surface modification, and fluorinated organic thin film transistors (OTFT). Nowadays, research into organic fluorine chemistry is typically centred on two primary areas: C-F bond formation, which involves a significant aspect of synthesis of artificial fluoride-containing compounds that rarely exist in nature, 7 and C-F bond cleavage, associated with the cleavage 8 and formation 9,10 of a highly stable C-F bond.…”

Silver-Catalyzed (Z)-β-Fluoro-vinyl Iodonium Salts from Alkynes: Efficient and Selective Syntheses of Z-Monofluoroalkenes

“…This bioisosterism has been employed to improve hydrolytic stability, , potency, − lipophilicity, and conformational rigidity by preventing E/Z ( s-cis/s-trans ) interconversion . Furthermore, monofluoroalkenes are intermediates toward alkyl fluorides and fluoropolymers. − …”

Stereoselective Rhodium(I)-Catalyzed C–F Bond Arylation of Tri- and Tetrasubstituted gem-Difluoroalkenes with Boronic Acids

“…In comparison, Rh­(I)-catalyzed C–C bond-forming reactions of fluorinated alkenes have been much less investigated . We have recently reported a Rh­(I)-catalyzed defluorinative coupling of boronic acids with monofluoroalkenes resulting in nonfluorinated alkene products (Scheme b) . However, the corresponding reaction of gem -difluoroalkenes to access monofluorinated products remains unknown (Scheme c).…”