Polymers, Dimers and Radical Cations from Electrochemical Oxidation of Interring-Bridged Thiophene and Thiophene-Phenylene Tetramers

Electronic and Optical Properties of 4H-Cyclopenta[2,1-b:3,4-b′]bithiophene Derivatives and Their 4-Heteroatom-Substituted Analogues: A Joint Theoretical and Experimental Comparison

“…The terminal alkyl groups (modeled as methyl groups in the calculations) were incorporated into the structures to increase the solubility of the compounds and also to increase the stability of the corresponding radical cations; 72 unsubstituted analogues of compounds of both types 1 and 2 typically exhibit irreversible electrochemistry due to polymerization of the radical ions. 6,9,10,24,25 The synthesis and characterization of the experimentally studied compounds are described in the Supporting Information, along with details of the computational methodology.…”

“…Compounds of type 2 containing a wide range of bridging groups, X, were studied experimentally, while a more limited set of compounds of type 1 were examined experimentally; DFT and TD-DFT calculations (B3LYP functional, 6-31G(d,p), and for calculating electron affinities (EAs), 6-31+G(d) basis sets) were performed for a wide range of compounds of both classes. The terminal alkyl groups (modeled as methyl groups in the calculations) were incorporated into the structures to increase the solubility of the compounds and also to increase the stability of the corresponding radical cations; unsubstituted analogues of compounds of both types 1 and 2 typically exhibit irreversible electrochemistry due to polymerization of the radical ions. ,,,, The synthesis and characterization of the experimentally studied compounds are described in the Supporting Information, along with details of the computational methodology.…”

“…Oligo- and polythiophenes are widely used in materials chemistry, especially as hole-transport materials for field-effect transistors (FETs) and as hole-transport and/or light-harvesting materials in solar cells. − Recently, a variety of thiophene-based fused-ring building blocks have been incorporated into materials of this type, including many 3,3′-bridged-2,2′-bithiophene three-ring systems of the type shown in Figure : i.e., 4 H -cyclopenta[2,1- b :3,4- b′ ]bithiophene (X = CH 2 ) − and related systems in which the bridging carbon atom in the 4-position is substituted (e.g., X = CR 2 , CF 2 , C(OCH 2 CH 2 O)) − or sp 2 hybridized (e.g., X = CO, CC(CN) 2 , CCRR′, CC(CN)(S(O) 2 R)) ,,− or in which it is replaced with a heteroatom-based group to afford a dithieno[3,2- b :2′,3′- d ]borole, dithieno[3,2- b :2′,3′- d ]silole (X = SiR 2 , SiAr 2 ), − dithieno[3,2- b :2′,3′- d ]pyrrole (X = NR, NAr), − dithieno[3,2- b :2′,3′- d ]phosphole (X = PR, PAr), − or one of the corresponding metal complexes (e.g., X = P(AuCl)Ph, P(W(CO) 5 )Ph), dithieno[3,2- b :2′,3′- d ]phosphole 4-oxide (X = P(O)R, P(O)Ar), − , dithieno[3,2- b :2′,3′- d ]phosphole 4-sulfide (X = P(S)Ar), dithieno[3,2- b :2′,3′- d ]thiophene (X = S), ,,− dithieno[3,2- b :2′,3′- d ]thiophene 4-oxide (X = SO), ,…”

Conformational locking for band gap control in 3,4-propylenedioxythiophene based electrochromic polymers

“…Ground-breaking work by Benincori et al has shown that conformation locking of polythiophene derivatives allows for a variable-length tether to control the electronic and optical properties of the polymer. [9][10][11][12][13][14] The groups of Swager and Roncali have used PEO-tethered polythiophene and PEDOT derivatives for applications in sensors. [15][16][17][18][19] Here, we use tethered macrocyclic dimers of 3,4-propylenedioxythiophenes (ProDOT), as schematically illustrated in Fig.…”