Multi-redox indenofluorene chromophores incorporating dithiafulvene donor and ene/enediyne acceptor units

• Christina Schøttler,
• Kasper Lund-Rasmussen,
• Line Broløs,
• Philip Vinterberg,
• Ema Bazikova,
• Viktor B. R. Pedersen and
• Mogens Brøndsted Nielsen

Beilstein J. Org. Chem. 2024, 20, 59–73, doi:10.3762/bjoc.20.8

• expanded by pyrrolo annelation. The optical and redox properties of these compounds, in some cases carbon-rich, were studied by UV–vis absorption spectroscopy and cyclic voltammetry. Synthetically, the work explores IF diones or fluorenone as central building blocks by subjecting the carbonyl groups to a

• pyrrole unit to one of the dithiole rings of an IF-TTF, allowing for dimerization of extended TTFs via the nitrogen atom by different linkers [14]. Donor–acceptor chromophores can be obtained by replacing one of the dithiafulvene (DTF) rings of the IF-TTF by an electron acceptor. Cyclic and acyclic

• (without an acetylenic moiety as in 20) are themselves poor photosensitizers for singlet oxygen. Electrochemistry Cyclic voltammograms of compounds 11, 13, 15, 16, and 17 (in MeCN for compounds 11 and 15 and in CH2Cl2 for compounds 13, 16, and 17, all with 0.1 M Bu4NPF6 as supporting electrolyte) are shown

Synthesis of N-acyl carbazoles, phenoxazines and acridines from cyclic diaryliodonium salts

• Nils Clamor,
• Mattis Damrath,
• Thomas J. Kuczmera,
• Daniel Duvinage and
• Boris J. Nachtsheim

Beilstein J. Org. Chem. 2024, 20, 12–16, doi:10.3762/bjoc.20.2

• Bremen, Germany 10.3762/bjoc.20.2 Abstract N-Acyl carbazoles can be efficiently produced through a single-step process using amides and cyclic diaryliodonium triflates. This convenient reaction is facilitated by copper iodide in p-xylene, using the commonly found activating ligand diglyme. We have

• of two equivalents of halogen salt waste. Their substitution with iodolium salts will be more sustainable since it reduces these unproductive halogenide salts by half. Due to our recent activity in the field of synthesis and applications of 5- and 6-membered cyclic iodonium salts, we searched for an

• diaryliodonium salts [29][31], as well as Pd-catalysed methods for synthesizing N-aryl carbazoles [32]. Similar procedures were published for the Cu-catalysed synthesis of aryl carbazoles from amines as well as other heterocycles such as N-acyl acridanes with nitriles using cyclic iodonium salts by Wen and Chen

Aldiminium and 1,2,3-triazolium dithiocarboxylate zwitterions derived from cyclic (alkyl)(amino) and mesoionic carbenes

• Nedra Touj,
• François Mazars,
• Guillermo Zaragoza and
• Lionel Delaude

Beilstein J. Org. Chem. 2023, 19, 1947–1956, doi:10.3762/bjoc.19.145

• cyclic (alkyl)(amino) or mesoionic carbenes (CAACs or MICs) onto carbon disulfide. Nine novel compounds were isolated and fully characterized by 1H and 13C NMR, FTIR, and HRMS techniques. Moreover, the molecular structures of two CAAC·CS2 and two MIC·CS2 betaines were determined by X-ray diffraction

• just three decades (Figure 1) [2]. In particular, cyclic diaminocarbenes based on the imidazoline, benzimidazole, or imidazole ring system (A–C) have led to a myriad of applications in organometallic chemistry, homogeneous catalysis, and materials science, to name just a few [3][4][5]. Due to their

• weaker basicity and greater modularity, the related 1,2,4-triazol-5-ylidene derivatives D have been mainly employed in organocatalysis [6]. Besides these four types of N-heterocyclic carbenes (NHCs), other families of cyclic compounds have been actively pursued to further expand the diversity of singlet

Construction of diazepine-containing spiroindolines via annulation reaction of α-halogenated N-acylhydrazones and isatin-derived MBH carbonates

• Xing Liu,
• Wenjing Shi,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2023, 19, 1923–1932, doi:10.3762/bjoc.19.143

• spirooxindoles [36][37][38][39][40][41][42][43]. In the presence of Lewis bases, isatin-derived MBH carbonates usually undergo [3 + 2] and [3 + 3] cycloaddition reactions with a broad range of active C–C and C–N double bonds and 1,3-dipolarpohiles to give various five- or six-membered cyclic spirooxindoles [44

• sequentially underwent a [4 + 3] cycloaddition reaction (reaction 1 in Scheme 1) [54]. Recently, Chen and co-workers reported a chiral tertiary amine-catalyzed asymmetric γ-regioselective [4 + 3] annulation reaction of isatin-derived MBH carbonates and cyclic 2-benzylidenebenzo[b]thiophen-3-ylidene

• cyclic 1,2-diazepine ring and the methylene unit is connected to the 3-positon of the oxindole moiety. On the basis of the current results and previous works [54][55][56][57][58][59][60][61], a reaction mechanism for the formation of the spiro[indoline-3,5'-[1,2]diazepines] has been proposed and is

Biphenylene-containing polycyclic conjugated compounds

• Cagatay Dengiz

Beilstein J. Org. Chem. 2023, 19, 1895–1911, doi:10.3762/bjoc.19.141

• biphenylenes and the emergence of a family of polycyclic hydrocarbons called [N]phenylenes. The utilization of cobalt-mediated alkyne trimerization facilitated the synthesis of [N]phenylenes exhibiting diverse structural configurations, including linear 7, angular 8, zig-zag 9, bent 10, branched 11, and cyclic

Aromatic systems with two and three pyridine-2,6-dicarbazolyl-3,5-dicarbonitrile fragments as electron-transporting organic semiconductors exhibiting long-lived emissions

• Karolis Leitonas,
• Brigita Vigante,
• Dmytro Volyniuk,
• Audrius Bucinskas,
• Pavels Dimitrijevs,
• Sindija Lapcinska,
• Pavel Arsenyan and
• Juozas Vidas Grazulevicius

Beilstein J. Org. Chem. 2023, 19, 1867–1880, doi:10.3762/bjoc.19.139

• of the compounds are sensitive to the medium. Cyclic voltammetry measurements indicate good hole-blocking and electron-injecting properties due to their high ionization potentials. Photoelectron spectroscopy and time-of-flight measurements reveal good electron-transporting properties for one of the

• derivatives 6–9. Their 5% weight loss temperatures (Td) ranged from 433 to 493 °C (Figure 5a and Table 1). Electrochemical properties The electrochemical properties of compounds 6–9 were studied by cyclic voltammetry (CV) selecting the electrochemical window from −1.6 to 1.7 V and the CV data were corrected

• delayed fluorescence. The optical band gaps of the compounds were determined to be 2.74–2.8 eV, while cyclic voltammetry measurements demonstrated that the compounds possess excellent hole-blocking properties due to their high ionization potentials. Moreover, they exhibited appropriate electron-injecting

N-Boc-α-diazo glutarimide as efficient reagent for assembling N-heterocycle-glutarimide diads via Rh(II)-catalyzed N–H insertion reaction

• Grigory Kantin,
• Pavel Golubev,
• Alexander Sapegin,
• Alexander Bunev and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2023, 19, 1841–1848, doi:10.3762/bjoc.19.136

• α-bromo (α-oxysulfonyl) glutarimide (3, Scheme 1, route B). Although the first approach has readily available starting reagents, a simple synthesis process, and gives generally high yields, it is restricted in terms of the type of heterocycle that can be assembled (primarily cyclic imides and

Selectivity control towards CO versus H₂ for photo-driven CO₂ reduction with a novel Co(II) catalyst

• Lisa-Lou Gracia,
• Philip Henkel,
• Olaf Fuhr and
• Claudia Bizzarri

Beilstein J. Org. Chem. 2023, 19, 1766–1775, doi:10.3762/bjoc.19.129

• Supporting Information File 1). The redox properties of 1 were investigated using cyclic voltammetry in a DMA solution with 0.1 M tetrabutylammonium hexafluorophosphate (TBAPF6) as the supporting electrolyte (Table 1). The concentration of the analyte was 5 mM. Only the cathodic scan resulted in a rich

• ), respectively. A more intense current arises with the third redox process occurring at −2.52 V, which could be assigned to the reduction localized on the ligand (compare with the cyclic voltammogram in Supporting Information File 1, Figure S8). We investigated the electrochemical properties also under a CO2

• -centered d–d transitions. Cyclic voltammetry of complex 1 in 0.1 M TBAPF6 solution of (a) DMA and (b) DMA/TEOA 5:1 (v/v). Black curves are registered under Ar and red curves are recorded under CO2 atmosphere. A glassy-carbon disk was used as the working electrode and the internal references used are (a

Unprecedented synthesis of a 14-membered hexaazamacrocycle

• Anastasia A. Fesenko and
• Anatoly D. Shutalev

Beilstein J. Org. Chem. 2023, 19, 1728–1740, doi:10.3762/bjoc.19.126

• ., vitamin B12, chlorophyll, metalloproteins, cyclic peptides, etc). PAMs themselves and their metal complexes exhibit various useful properties [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31], particularly, they possess a wide range of biological activities and are used as contrast

• synthesis of novel PAMs with interesting properties is of great importance. Recently, we developed some approaches to 14-membered cyclic bis-semicarbazones [32][33][34][35] and bis-thiosemicarbazone [36], namely 7,14-dimethyl-1,2,4,8,9,11-hexaazacyclotetradeca-7,14-diene-3,10-diones and -3,10-dithiones. The

Effects of the aldehyde-derived ring substituent on the properties of two new bioinspired trimethoxybenzoylhydrazones: methyl vs nitro groups

• Dayanne Martins,
• Roberta Lamosa,
• Talis Uelisson da Silva,
• Carolina B. P. Ligiero,
• Sérgio de Paula Machado,
• Daphne S. Cukierman and
• Nicolás A. Rey

Beilstein J. Org. Chem. 2023, 19, 1713–1727, doi:10.3762/bjoc.19.125

• azomethine nitrogen N1 as H-acceptor is observed, which originates six-membered cyclic motifs with a graph-set (6) [39]. The hydrogen atom is closer to O1 than to N1, indicating that the preferred protonation site is the former, as can be observed at the Fourier difference maps (Figure S1A and S1B in

Decarboxylative 1,3-dipolar cycloaddition of amino acids for the synthesis of heterocyclic compounds

• Xiaofeng Zhang,
• Xiaoming Ma and
• Wei Zhang

Beilstein J. Org. Chem. 2023, 19, 1677–1693, doi:10.3762/bjoc.19.123

• group on the α-carbon atom are semi-stabilized (Scheme 1) [16]. The B1-type AMYs can be generated from the decarboxylative condensation of aldehydes with α- and N-dialkylglycines or from cyclic amino acids (such as proline) [31][32][33], while AMYs of type B2 are accessible through the decarboxylative

• (such as C60/C70 fullerenes) [56][57][58]. Other than amino esters and amino acids shown in Scheme 1, cyclic amines can also react with arylaldehydes to form B1-type semi-stabilized AMYs. In this context, the Seidel group reported the reactions of pyrrolidines 5 with arylaldehydes for the formation of

• AMYs B1 which then were reacted with nucleophiles to form C–H-functionalized pyrrolidines or subjected to the 1,3-dipolar cycloaddition with olefins to afford bicyclic compounds (Scheme 2A and B) [59][60]. We employed cyclic amines for the synthesis of spirooxindole-pyrrolidines 7a or 7b in good

A deep-red fluorophore based on naphthothiadiazole as emitter with hybridized local and charge transfer and ambipolar transporting properties for electroluminescent devices

• Suangsiri Arunlimsawat,
• Patteera Funchien,
• Pongsakorn Chasing,
• Atthapon Saenubol,
• Taweesak Sudyoadsuk and
• Vinich Promarak

Beilstein J. Org. Chem. 2023, 19, 1664–1676, doi:10.3762/bjoc.19.122

• optoelectronic devices. The electrochemical behavior of TPECNz was analyzed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) in CH2Cl2 containing 0.1 M n-Bu4NPF6 as a supporting electrolyte. As illustrated in Figure 5b, the molecule shows multiple quasi-reversible oxidation and reduction

• illumination). a) DSC and TGA thermograms measured at a heating rate of 10 °C min−1 under N2 flow. b) Cyclic voltammogram (CV) and differential pulse voltammogram (DPV) analyzed in dry CH2Cl2 at a scan rate of 50 mV s−1 under an argon atmosphere (insert: HOMO/HOMO−1/LUMO orbitals). a) Schematic structure of

Benzoimidazolium-derived dimeric and hydride n-dopants for organic electron-transport materials: impact of substitution on structures, electrochemistry, and reactivity

• Swagat K. Mohapatra,
• Khaled Al Kurdi,
• Samik Jhulki,
• Georgii Bogdanov,
• John Bacsa,
• Maxwell Conte,
• Tatiana V. Timofeeva,
• Seth R. Marder and
• Stephen Barlow

Beilstein J. Org. Chem. 2023, 19, 1651–1663, doi:10.3762/bjoc.19.121

• crystallographically characterized. Electrochemistry The 1+, 1H, and 12 species were investigated using cyclic voltammetry in THF/0.1 M Bu4NPF6 at a scan rate of 50 mV s−1. The voltammograms (shown for one series of compounds in Figure 6) were qualitatively similar to those reported and shown elsewhere for other

• , resulting in 1g• and 1h• being more reducing monomers than their non-methoxylated analogues 1b• and 1e•, respectively. Cyclic voltammograms of both 1H and 12 both reveal irreversible oxidations (with the corresponding 1+ reductions seen in subsequent reductive cycles, see Figure 6 for examples). These 1H

• (located and refined for 1bH, geometrically placed for the others). Structures of the cations from the single crystal structures of 1g+I− (left), 1h+PF6− (center), and 1i+PF6− (right), shown with 50% thermal ellipsoids and excluding hydrogen atoms and counter anions. Cyclic voltammograms (50 mV s−1, THF

Tying a knot between crown ethers and porphyrins

• Maksym Matviyishyn and
• Bartosz Szyszko

Beilstein J. Org. Chem. 2023, 19, 1630–1650, doi:10.3762/bjoc.19.120

• other two have imine character [11][12]. They are rigid, planar molecules which feature macrocyclic aromaticity due to the cyclic delocalisation of π electrons [13]. The well-defined macrocyclic cavity termed the coordination core, can encompass one, two, or more central ions (typically metal/metalloid

• cations), forming coordination compounds wherein the central ion acquires a square planar [14], square pyramidal [15], or an octahedral coordination environment [16]. On the opposite side, crown ethers are cyclic molecules composed of carbon and oxygen atoms forming the macrocycle. Depending on the size

• with trifluoroacetic acid (TFA) resulted in a cationic 40-H+. Cyclic voltammetry and differential pulse voltammetry were performed to investigate the electrochemical properties of 40-H+. The cation exhibited two reversible oxidations and two to three reductions. The redox potentials were influenced by

A series of perylene diimide cathode interlayer materials for green solvent processing in conventional organic photovoltaics

• Kathryn M. Wolfe,
• Shahidul Alam,
• Eva German,
• Fahad N. Alduayji,
• Maryam Alqurashi,
• Frédéric Laquai and
• Gregory C. Welch

Beilstein J. Org. Chem. 2023, 19, 1620–1629, doi:10.3762/bjoc.19.119

• properties of the four CILs were probed using solution cyclic voltammetry (CV; Figure 4) and differential pulse voltammetry (DPV; Supporting Information File 1, Figures S27–S30), using dichloromethane as the solvent. For all reversible reduction or oxidation waves, HOMO and LUMO energy levels were determined

Radical chemistry in polymer science: an overview and recent advances

• Zixiao Wang,
• Feichen Cui,
• Yang Sui and
• Jiajun Yan

Beilstein J. Org. Chem. 2023, 19, 1580–1603, doi:10.3762/bjoc.19.116

• necessary. MF-ROMP, also termed photo-ROMP, is a novel technique to polymerize cyclic olefins. It begins with the reductive quenching of an photoexcited photocatalyst (PC) at an enol ether initiator to produce a radical cation carrier [90]. Then, the carrier undergoes cyclic addition with a cyclic olefin

• soluble upon radiation, respectively. Some early negative photoresists undergo a photochemical crosslinking process of 1,3-diene cyclic polymers [190] (cf. section 3.2), but such systems are no longer studied due to the poor resolution and sensitivity. On the other hand, positive resists based on

Cyclodextrins permeabilize DPPC liposome membranes: a focus on cholesterol content, cyclodextrin type, and concentration

• Ghenwa Nasr,
• Hélène Greige-Gerges,
• Sophie Fourmentin,
• Abdelhamid Elaissari and
• Nathalie Khreich

Beilstein J. Org. Chem. 2023, 19, 1570–1579, doi:10.3762/bjoc.19.115

• content membrane increase. Keywords: cholesterol; cyclodextrins; liposome; membrane permeability; Introduction Cyclodextrins (CDs) are a family of cyclic oligosaccharides made of glucopyranose units connected by α-1,4-glycosidic bonds. They possess a cone-shaped molecular structure with a hydrophobic

Complexes of resorcin[4]arene with secondary amines: synthesis, solvent influence on “in-out” structure, and theoretical calculations of non-covalent interactions

• Waldemar Iwanek

Beilstein J. Org. Chem. 2023, 19, 1525–1536, doi:10.3762/bjoc.19.109

• substituents with R[4]A in ethanol were synthesized. The composition of the complexes was determined based on the integration of amine proton signals in the 1H NMR spectra. For small molecule sec-amines such as N,N-dimethylamine, N,N-diethylamine, and cyclic amines (pyrrolidine, piperidine, morpholine, N

• “in” complexes. These are amines in which the size of the alkyl groups does not exceed the size of the ethyl group and cyclic sec-amines with five and six-membered rings. Pyrrolidine is the sec-amine that is most “structurally matched” to the size of the R[4]A cavity. For amines with longer alkyl

Synthesis and biological evaluation of Argemone mexicana-inspired antimicrobials

• Jessica Villegas,
• Bryce C. Ball,
• Katelyn M. Shouse,
• Caleb W. VanArragon,
• Ashley N. Wasserman,
• Hannah E. Bhakta,
• Allen G. Oliver,
• Danielle A. Orozco-Nunnelly and
• Jeffrey M. Pruet

Beilstein J. Org. Chem. 2023, 19, 1511–1524, doi:10.3762/bjoc.19.108

• iminium group. In addition to assessing how the effects of the above berberine modifications could enhance the activity of B1, we also examined the influence of the rigid cyclic structure of compound B1 by preparing the non-cyclic charged variants B12 and B13 (Scheme 4). Our exploration of non-cyclic

• B13 can change its charge state depending on local environment, while the methylated derivative B12 remains a fixed-charge species. While some previous reports have pointed to the cyclic structure as essential for berberine activity, these non-cyclic variants did show some modest activity, albeit

• desired derivatives. Unexpected oxidation side-product B2, B4, and B6 were also isolated from certain reaction mixtures. Direct modification of the original berberine structure. Preparation of non-cyclic charged variants of B1. Partial reduction of compound B1 to B14. Synthesis of the substituted 2

Unraveling the role of prenyl side-chain interactions in stabilizing the secondary carbocation in the biosynthesis of variexenol B

• Moe Nakano,
• Rintaro Gemma and
• Hajime Sato

Beilstein J. Org. Chem. 2023, 19, 1503–1510, doi:10.3762/bjoc.19.107

• 180,000 terpenoid compounds have been reported to date [1][2][3][4]. One of the most intriguing point is that all diversified structures are synthesized from common starting materials, isoprenoids. Reactions that generate complex cyclic structures and multiple stereocenters from linear achiral precursors

N-Sulfenylsuccinimide/phthalimide: an alternative sulfenylating reagent in organic transformations

• Fatemeh Doraghi,
• Seyedeh Pegah Aledavoud,
• Mehdi Ghanbarlou,
• Bagher Larijani and
• Mohammad Mahdavi

Beilstein J. Org. Chem. 2023, 19, 1471–1502, doi:10.3762/bjoc.19.106

• first thiolation and intramolecular cyclization of propargyl azides the removal of N2 and a proton. Subsequently, monothiolated perroles were subjected to the second thiolation process to prepare 3,4-bisthiolated pyrroles. Cyclic voltammetry and DFT calculations revealed that the 3,4-bisthiolated

• formation of three-membered cyclic sulfonium ion II followed by ring-opening of sulfonium ion and intramolecular cyclization. The use of a Lewis base/Brønsted acid catalysis system for the sulfenylation of aromatic substrates 4 was reported by Gustafson et al. (Scheme 55) [87]. In the method, catalyst P

• cyclization transformation involving activation of the electrophilic sulfur reagent by PhSePh with the assistance of TMSOTf to form transition state I. Intermediate II formed through capturing of sulfonium by selenium. Then, II reacted with 136 to give regioselective cyclic thiiranium ion III. Nucleophilic

Application of N-heterocyclic carbene–Cu(I) complexes as catalysts in organic synthesis: a review

• Nosheen Beig,
• Varsha Goyal and
• Raj K. Bansal

Beilstein J. Org. Chem. 2023, 19, 1408–1442, doi:10.3762/bjoc.19.102

• atom(s) or another heteroatom into the vacant p-orbital (LUMO) at the carbene carbon atom (Figure 2). In fact, the donation of lone pair electrons to the carbenic center leads to an ylidic structure which induces a “push–pull” effect thereby enhancing the stability of the NHC. The cyclic structure of

• . The hydrosilylation of aryl, alkyl, and cyclic ketones could be accomplished with excellent yields (Scheme 35) [48]. In 2011, Gawley and co-worker reported an excellent reactivity and enantioselectivity of a C2-symmetric NHC–Cu(I) complex for the catalytic hydrosilylation of a variety of carbonyl

• arylaluminium reagents to five-, six-, and seven-membered β-substituted cyclic enones (Scheme 42). It is obvious that the NHC–Cu(I) complexes are generated in situ through transmetallation. For arylation reactions, Me2(Ar)Al reagents were used. The substrates having a variety of substituents (R = CH2Bn, n-Bu

Visible-light-induced nickel-catalyzed α-hydroxytrifluoroethylation of alkyl carboxylic acids: Access to trifluoromethyl alkyl acyloins

• Feng Chen,
• Xiu-Hua Xu,
• Zeng-Hao Chen,
• Yue Chen and
• Feng-Ling Qing

Beilstein J. Org. Chem. 2023, 19, 1372–1378, doi:10.3762/bjoc.19.98

• primary carboxylic acids but also secondary carboxylic acids (3n−s). We were pleased to find that cyclic carboxylic acids, including strained 3- and 4-membered rings, participated in this transformation and delivered the corresponding products in good yields. It should be mentioned that aromatic and more

Synthesis of ether lipids: natural compounds and analogues

• Marco Antônio G. B. Gomes,
• Alicia Bauduin,
• Chloé Le Roux,
• Romain Fouinneteau,
• Wilfried Berthe,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2023, 19, 1299–1369, doi:10.3762/bjoc.19.96

• acyl group. Then, the phosphocholine polar head group was introduced with a sequential one-pot procedure using first 2-chloro-2-oxo-1,3,2-dioxaphospholane (12.7) to produce a cyclic phosphate as intermediate that subsequently reacted with trimethylamine to produce thio-PAF 12.8. The opening of

• produce 15.2a [99] (Figure 15A and B) or with functionalized furane to produce 15.2b. The acylation was also achieved by reaction with cyclic acid anhydride to place in ω-position a carboxylic acid function as exemplified with 15.3a [98]. The acetyl group present in the structure of PAF in position sn-2

• 22.10. However, the last step features the lower yield (54%) of this 8-step synthesis. In 1994, Bittman et al. reported an alternative strategy to introduce the phosphocholine moiety by the preparation of a cyclic phosphite as a key intermediate [119]. This one-pot three-step sequence starts with the

Organic thermally activated delayed fluorescence material with strained benzoguanidine donor

• Alexander C. Brannan,
• Elvie F. P. Beaumont,
• Nguyen Le Phuoc,
• George F. S. Whitehead,
• Mikko Linnolahti and
• Alexander S. Romanov

Beilstein J. Org. Chem. 2023, 19, 1289–1298, doi:10.3762/bjoc.19.95

• significantly shorter (0.4 Å) than the 3.74(3) Å average distance between nearest neighbor carbazole ligands in 4CzIPN, indicative for much stronger intermolecular interactions. Cyclic voltammetry was used to analyze the redox behavior of 4BGIPN in THF solution containing [n-Bu4N]PF6 as supporting electrolyte

• recorded using a Bruker AVIII HD 500 MHz NMR spectrometer. 1H NMR spectra (500.19 MHz) and 13C{1H} (125.79 MHz) were referenced to dichloromethane-d2 at δ 5.32 (13C, δ 53.84). All electrochemical experiments were performed using an Autolab PGSTAT 302N computer-controlled potentiostat. Cyclic voltammetry

• ) possible isomers for 4BGIPN material. Ellipsoids are shown at the 50% level where hydrogen atoms are omitted for clarity. Full range cyclic voltammogram for 4BGIPN. Recorded using a glassy carbon electrode in THF solution (1.4 mM) with [n-Bu4N]PF6 as supporting electrolyte (0.13 M), scan rate 0.1 Vs−1. UV