Novel unsymmetrically functionalized BEDT–TTF derivatives: synthesis, crystal structure and electrochemical characterization

Abstract

Novel functionalized bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) derivatives 4 and 5 have been synthesized in good yields from cyano precursor via a cross-coupling reaction. Their redox potentials have been studied by cyclic voltammetry in a dichloromethane solution; this indicated that they are slightly weaker electron donors than BEDT-TTF. Compound 4 has been studied by X-ray crystallography; this revealed that, in the crystal, the molecules were held together by some unconventional C-H•••N and C-H•••S hydrogen bonds.

Ferromagnetic versus Antiferromagnetic Exchange Interactions in Tetrathiafulvalene‐Based 3d/4f Heterobimetallic Complexes

“…Similar phenomena have been previously observed 18b. Finally, the coordination of the Ln(hfac) 3 complex led to a new very intense absorption band at 32 500 [32 700] cm −1 (Figure 6c and d), which is usually attributed to π–π* intra‐hfac − transitions 6a,b. 7g,h,k,l The electrostatic effect of the coordination of Ln(hfac) 3 can be observed by an additional redshift of the TTF→salphen CT (400 cm −1 ).…”

“…The absorption spectrum of the TTF‐salphen 2− donor was deconvoluted in five Gaussian contributions (Figure S7a). Considering the previous works on the optical properties of the TTF derivatives,6a,b, 7l, 18 the lowest‐energy band (absorption band at 26 100 cm −1 ) can be attributed to intraligand charge transfer (CT) from the TTF core to the salphen 2− acceptor. Using the previously reported data,15 the deconvolutions centered to 29 800, 33 000, 36 000, and 42 400 cm −1 can be attributed to intraligand CT from the phenol to salphen 2− acceptor, n–π*/π–π* intraphenol transitions and n–π*/π–π* intra‐azomethine transitions, respectively.…”

Unprecedented Sensitization of Visible and Near‐Infrared Lanthanide Luminescence by Using a Tetrathiafulvalene‐Based Chromophore

“…The cyclic voltamograms show two mono‐electronic oxidations at about 0.54 and 0.89 V for L , which correspond to the formation of a TTF radical cation and a dication, respectively (Figure S1 in the Supporting Information). These oxidation potentials are almost the same to those found for the bis(ethylenedithia) (BEDT)–TTF donor (0.52 and 0.94 V) 17. Upon coordination of the lanthanide, both E 1 1/2 and E 2 1/2 remain similar to the potentials of the free ligand (Table S4 in the Supporting Information).…”

Tetrathiafulvalene-based group XV ligands: Synthesis, coordination chemistry and radical cation salts

“…An extensive series of bis(pyridylmethylthio)-TTF derivatives 51-59 was prepared by two different routes (Scheme 15): (i) unsymmetrical phosphite coupling involving a pyridylfunctionalized 1,3-dithiole-2-one molecule or (ii) alkylation of a TTF dithiolate with the appropriate halomethylpyridine derivative [42][43][44][45][46]. It is worth noting that according to the second strategy and starting from bis(cyanoethylseleno)TTF derivatives, the corresponding TTFs 57 and 58 bearing two 3-or 4-pyridyl groups linked to the selenium atom have been synthesized [43].…”

“…triethylphosphite [44] or through the functionalization of the preformed dithiolate TTF core [70]. The influence of the pyrazine group on the electron-donating ability of the TTF core has been analyzed electrochemically.…”