Conversion of Carbon–Fluorine Bonds α to Transition Metal Centers to Carbon–Hydrogen, Carbon–Carbon, and Carbon–Heteroatom Bonds

Abstract

Pseudo‐tetrahedral primary fluoroalkyl complexes of iridium provide a template on which to study the stereoselectivity of carbon–fluorine bond activation α to iridium by external protic acids. Coupled with migration of internal nucleophiles, this reaction leads to diastereoselective formation of new carbon–oxygen, carbon–sulfur, carbon–hydrogen, and carbon–carbon bonds. Stereochemical studies of the conformational properties of starting fluoroalkyl complexes and relativestereocenter configurations for diastereomeric products, together with kinetic studies of reactions in different solvents, allow a self‐consistent mechanism for these reactions to be established. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

Fluorine as a ligand substituent in organometallic chemistry: A second chance and a second research career

“…But as soon as the counterion was replaced with one incapable of such hydrogen-bonding, such as B(ArF) 4 À , a rapid hydrolysis of the a- combined to afford a facile hydrolysis [78,79]. Secondary fluoroalkyl groups were much less reactive and a conformational rationale for this has been put forth recently [80].…”

Hydrodefluorination of carbon–fluorine bonds by the synergistic action of a ruthenium–palladium catalyst

“…Carbon-fluorine bonds are considered as the most passive organic functionalities [7][8][9] , and their selective activation under mild conditions remains poorly achieved. Although there has been considerable progress in the stoichiometric activation of C-F bonds, the metalcatalysed versions of the process remain relatively scarce 5,[10][11][12][13][14][15][16][17][18][19][20][21] . The simplest modification of the C-F bond is its transformation to the simple C-H bond (hydrodefluorination, HDF), a process that has been mainly limited to fluoroarenes, with very few examples referring to trifluoromethylarenes and other perfluoroalkyl groups 1,[22][23][24][25][26] .…”

Palladium-Mediated Organofluorine Chemistry

“…The hydrolysis of difluorocarbenes is a well-known process that leads to the formation of a carbonyl ligand. 319,320 The insertion of the CO ligand into the Pd-Ar bond and its subsequent elimination with the remaining fluoride produces benzoyl fluoride, one the observed species in this reaction. Supporting this interpretation, several of the expected decomposition products have been found in the reaction media.…”

“…319 The reactivity of transition metal perfluoroalkyls via α-fluorine activation has been recently reviewed. 320 Since transition metal fluorocarbenes are highly reactive species they often react before being isolated. In palladium chemistry there are no reports on stable, isolated fluorocarbenes derived of alpha-fluorine elimination in fluoroalkyl palladium compounds.…”