Perfluoroalkylation reactions of (hetero)arenes

Abstract

Perfluoroalkylation reactions of arenes have not been the subject of intense study as has been the case for the trifluoromethylation reactions of aromatics. However, the new synthetic methods proposed for achieving homolytic aromatic substitution reactions with perfluoroalkyl moieties have begun to claim a relevant role in functionalization reactions, as revealed by the interesting properties of arenes with large perfluoroalkyl chains. Methods for achieving Ar-R f bonding reactions can be classified into thermal and photochemical, which can in turn make use of transition metals or be non-metal catalyzed. Reactions are mainly radical in nature. Radical methods for introducing R f moieties into arenes have resulted as being the most popular and versatile options available to synthetic chemists.Scheme 3 Thermal radical perfluoroalkylation of arenes.Scheme 4 Perfluoroalkylation of heteroarenes employing perfluorocarboxylic anhydrides.Scheme 5 Perfluoroalkylation of dinitrobenzenes. 62500 | RSC Adv., 2015, 5, 62498-62518 This journal is Scheme 29 Lewis acid-mediated perfluoroalkylation of (hetero)arenes in the presence of IF 5 . Scheme 30 Perfluoroalkylation of arenes. This journal isScheme 38 Scope of the PET perfluoroalkylation of N,N-disubstituted aromatic amines.Scheme 39 Proposed mechanism for the PET perfluoroalkylation of N,N-disubstituted aromatic amines.Scheme 40 Photoinduced perfluorobutylation of (di)benzo(hetero)arenes. This journal isScheme 41 Proposed mechanism for the perfluorobutylation of dibenzoheteroarenes in aqueous mixtures.Scheme 42 Scope of the Ti-photocatalyzed reaction of arenes. Scheme 43 Proposed TiO 2 -photocatalyzed perfluoroalkylation of arenes. Scheme 44 Generation of perfluoroalkyl radicals by TiO 2 -photocatalyzed one electron reduction of perfluoroalkyliodides. 62514 | RSC Adv., 2015, 5, 62498-62518 This journal is Scheme 45 TiO 2 -photocatalytic aromatic perfluoroalkylations of p-xylene.Scheme 46 Direct C-H difluoromethylenephosphonation of (hetero) arenes.Scheme 47 Mechanism proposed for the direct C-H difluoromethylenephosphonation of (hetero)arenes. This journal is

Direct Copper‐Catalyzed C‐H Monofluoroalkylation of Benzoxazoles with 1‐Fluoro‐1‐haloalkanes

“…C–H to C–F exchange in organic molecules often results in significant variation in their chemical, physical, and biological properties, including increase in metabolic stability, lipophilicity, and bioavailability As such, a variety of fluoroalkylation reagents and methodologies have been developed to fulfill the increasing demand of fluoroalkylated (hetero)arenes for pharmaceutical and agrochemical chemistry . Compared with methods for trifluoromethylation, perfluoroalkylation and difluoroalkylation[2d], of (hetero)arenes, the direct introduction of a monofluoroalkyl group (i.e., monofluoroalkylation) is still in a relatively underdeveloped stage . Selective monofluoroalkylation of (hetero)arenes is mainly performed by transition metal mediated or catalyzed cross‐coupling reactions of (hetero)aryl based electrophiles or nucleophiles with fluoro(halo)‐organic compounds (Scheme a) .…”

[(bpy)CuSCF3]: A Practical and Efficient Reagent for the Construction of C–SCF3 Bonds

“…Considering the significance of fluorinated substituents, numerous synthetic approaches have been reported. [3][4][5][6][7][8] Particularly, molecular scaffolds containing trifluoromethylthio (-SCF 3 ) substituents attract great interest as pharmaceuticals, agrochemicals, and functional materials, owing to their strong electron-withdrawing effect and hydrophobicity parameter ( R = 1.44 and 1.29, respectively). 9 Therefore, strategies for the efficient synthesis of molecules bearing the -SCF 3 group have developed considerably.…”

Trifluoroethoxy-Coated Phthalocyanine Catalyzes Perfluoroalkylation of Alkenes under Visible-Light Irradiation

“…Perfluoroalkyl groups frequently appeared in the libraries of pharmaceuticals, agrochemicals, and functional materials and in the methods for the introduction of perfluoroalkyl groups to organic molecules, causing a massive accumulation of literature over the past few decades [ 1 , 2 , 3 , 4 , 5 ]. Radical perfluoroalkylation of alkenes using perfluoroalkyl halides (Rf-X) under shortwave UV irradiation is one of the classical and well-explored methods for this purpose [ 6 , 7 , 8 ].…”