Pentafluorophenyl copper: aggregation and complexation phenomena, photoluminescence properties, and applications as reagent in organometallic synthesis

Abstract

Recent advances in the chemistry of pentafluorophenyl copper are discussed, including the observation of strongly luminescent adducts with pyridine, the first successful structural characterization of an organocopper-arene complex, and the complexation with electron-rich transition metal complexes such as ferrocene derivatives. In addition, new applications in synthetic organometallic chemistry are discussed, which include the discovery of tin/copper exchange reactions for the preparation of organocopper compounds that are otherwise not readily accessible, and the selective transfer of the C(6)F(5) groups to boron to form catalytically active and electronically interesting organoboron polymers.

Structure and reactivity of a planar chiral naphthylferrocenylcopper heteroaggregate

“…In earlier work we found that (C 6 F 5 Cu) 4 and (MesCu) n (Mes = 2,4,6-trimethylphenyl; n = 4, 5) can serve as mild reagents for the transfer of aryl groups to boron [3,8]. In fact, the reagent (C 6 F 5 Cu) 4 has been successfully employed in areas ranging from molecular Lewis acid chemistry [9,10] to polymeric Lewis acids [11], conjugated materials [12], and even amphiphilic borate block copolymers [13].…”

“…Pentafluorophenyl copper, which was first introduced by Cairncross and Sheppard more than 40 years ago [1], exists as a tetrameric aggregate in the solid state, which is also believed to be the predominant species in solution [2,3]. A variety of structurally intriguing complexes with Lewis bases have been reported also and, in recent years, the electron-deficient character of pentafluorophenyl copper has been exploited in the assembly of luminescent supramolecular structures [4,5].…”

Controlling the ligating behaviour of biologically important p-hydroxybenzoate towards copper(II) by the use of nitrogen bases: Synthesis, characterization and single crystal X-ray structure determination of [trans-Cu(en)2(H2O)2](L1)2·2H2O and [cis-Cu(L1)2(L2)2] where en=ethylenediamine, L1=p-hydroxybenzoate, L2=3-picoline

“…Copper(II) complexes continue to receive attention [1] because of chemical, biological and industrial importance. Inorganic chemistry of copper(II) is fascinating owing to: (i) copper(II) exhibits a variety of coordination number (4)(5)(6)(7)(8) with associated geometries (ii) copper(II) complexes are liable to Jahn-Teller distortion, (iii) the anionic ligand may be non coordinated or coordinated, (iv) it is one of constituent metal ions in most of superconductors and (v) the copper(II) compounds for (e.g. carboxylates) may be monomeric, dimeric or polymeric.…”

“…Industrial applications of copper salts include electroplating, as catalysts (copper(II)triflate), as insecticide, ink and paints (cupric phthalocyaninate), cupric b-diketonates as precursor for deposition of thin films of copper by chemical vapour deposition, reagent in organic synthesis etc. [5]. Cu (hexafluoroacetylacetonate) 2 is widely used in synthesis of molecular magnets [6].…”

Alkali/coinage metals—organolithium, organocuprate chemistry

“…97 Meanwhile, in a structural vein, the aggregation and complexation behaviour of pentafluorophenyl copper has been discussed, along with its applicability to photochemistry and organometallic synthesis. 98 a-Halonitriles have been converted into reactive metallated nitriles using alkyllithium, organomagnesium, and lithium dimethylcuprate substrates. Subsequent reactivity varies, with lithiated and magnesiated nitriles reacting with propargyl bromide by S N 2 displacement but with C-metallated organocopper nitriles evidently converting through an S N 2 0 route.…”