78196-92-6Relevant articles and documents
Searching for Models Exhibiting High Circularly Polarized Luminescence: Electroactive Inherently Chiral Oligothiophenes
Benincori, Tiziana,Appoloni, Giulio,Mussini, Patricia Romana,Arnaboldi, Serena,Cirilli, Roberto,Quartapelle Procopio, Elsa,Panigati, Monica,Abbate, Sergio,Mazzeo, Giuseppe,Longhi, Giovanna
, p. 11082 - 11093 (2018/08/01)
Two new inherently chiral oligothiophenes characterized by the atropisomeric 3,3′-bithianaphtene scaffold functionalized with fused ring bithiophene derivatives, namely 4H-cyclopenta[2,1-b3:4b′]dithiophene (CPDT) and dithieno[3,3-b:2′,3′-d]pyrrole (DTP), were synthesized. The racemates were fully characterized and resolved into antipodes by enantioselective HPLC. The enantiomers were analyzed through different chiroptical techniques: electronic circular dichroism (ECD) and vibrational circular dichroism (VCD) were employed to attribute the absolute configuration (AC). Comparison of experimental and calculated VCD spectra confirmed the DFT calculated conformational characteristics. The compound functionalized with two CPDT units was oxidized with FeCl3, and ECD and CPL of the resulting material were measured. Circularly polarized luminescence (CPL) was measured to verify if inherently chiral oligothiophenes could be promising systems for chiral photonics applications.
Dinuclear rhenium complexes as redox-active pendants in a novel electrodeposited polycyclopentadithiophene material
Procopio, Elsa Quartapelle,Bonometti, Valentina,Panigati, Monica,Mercandelli, Pierluigi,Mussini, Patrizia R.,Benincori, Tiziana,D'Alfonso, Giuseppe,Sannicol, Francesco
, p. 11242 - 11251 (2015/01/09)
The novel [Re2(μ-H)(μ-OOC-CPDT)(CO)6(μ-3-Me-pydz)] complex (1; OOC-CPDT = 4H-cyclopenta[2,1-b:3,4-b′]dithiophene-4-carboxylate, 3-Me-pydz = 3-methylpyridazine) has been prepared and characterized by single-crystal X-ray diffraction, density functional theory (DFT), and time-dependent DFT computations, UV-vis absorption and emission spectroscopy, and cyclic voltammetry (CV). The measured properties indicate the lack of electronic communication in the ground state between the CPDT and the rhenium diazine moieties. Oxidative electropolymerization of 1, achieved by repeated potential cycling (-0.4 to +1.0 V vs Fc+/Fc, in acetonitrile) with different supporting electrolytes, on different electrodes, afforded an electroactive and stable metallopolymer (poly-1). In situ measurements of the mass of the growing film (on a gold electrode, with an electrochemical quartz microbalance) confirmed the regularity of the polymerization process. The polymer exhibits two reversible oxidation peaks of the thiophene chain and a broad irreversible reduction peak (-1.4 V, quite close to that observed for the reduction of monomer 1), associated with a remarkably delayed sharp return peak, of comparable associated charge, appearing in close proximity (+0.3 V) to the first oxidation peak of the neutral polythiophene chain. This charge-trapping effect can be observed upon repeated cycles of p and n doping, and the negative charge is maintained even if the charged electrode is removed from the solution for many hours. Electrochemical impedance spectroscopy showed that the main CV oxidation peak corresponds to facile charge transfer, combined with very fast diffusion of both electrons and ions within the polymer. In summary, poly-1 provides a new example of a metallopolymer, in which the conductive properties of the π-conjugated system are added to the redox behavior of the pendant-isolated complexes. (Figure Presented).
A Study of Some Thiophene Analogues of Glycolic Acid
Jeffries, Alfred T.,Moore, Kenneth C.,Ondeyka, Debra M.,Springsteen, Arthur W.,MacDowell, Denis W.H.
, p. 2885 - 2889 (2007/10/02)
Reaction of phenyl(3-thienyl)glycolic acid (1) with AlCl3 in benzene solution leads to the formation of 4H-indenothiophene-4-carboxylic acid (2) whereas analogous reaction of phenyl(2-thienyl)glycolic acid (4) produces no indenothiophene but only a mixture of 5 and 6.In the case of di-(2-thienyl)glycolic acid (14b) and di-(3-thienyl)glycolic acid (16b) analogous results are obtained, with the former leading to the formation of 15 and the latter producing 17.In the case of the (benzothienyl)phenylglycolic analogues of 1 and 4 the acids were unstable to heat so that the esters, ethyl (2-benzothienyl)phenylglycolate (21) and ethyl (3-benzothienyl)phenylglycolate (20), upon treatment with AlCl3 in benzene led to cyclized products only.The former gave 23 which was saponified and decarboxylated to yield 25 and compared with an authentic sample obtained by synthesis.Ester 20 similarly gave 22 which was similarly converted to the known 24.A mechanistic explanation of these findings is proposed.
