CF₃SO₂X (X = Na, Cl) as reagents for trifluoromethylation, trifluoromethylsulfenyl-, -sulfinyl- and -sulfonylation. Part 1: Use of CF₃SO₂Na

• Hélène Guyon,
• Hélène Chachignon and
• Dominique Cahard

Beilstein J. Org. Chem. 2017, 13, 2764–2799, doi:10.3762/bjoc.13.272

• , pyrimidine, thiophene, etc. the Maiti group reported an alternative approach toward α-trifluoromethyl ketones starting from (hetero)arylacetylenes 7 and also aliphatic terminal alkynes 8 (Scheme 5) [24]. The trifluoromethyl radical was generated from CF3SO2Na as indicated earlier, oxygen from air was the

Rh(II)-mediated domino [4 + 1]-annulation of α-cyanothioacetamides using diazoesters: A new entry for the synthesis of multisubstituted thiophenes

• Jury J. Medvedev,
• Ilya V. Efimov,
• Yuri M. Shafran,
• Vitaliy V. Suslonov,
• Vasiliy A. Bakulev and
• Valerij A. Nikolaev

Beilstein J. Org. Chem. 2017, 13, 2569–2576, doi:10.3762/bjoc.13.253

• reactions of acyclic diazoesters with α-cyanothioacetamides. It provides a way for the preparation of 5-amino-3-(alkoxycarbonylamino)thiophene-2-carboxylates, 2-(5-amino-2-methoxycarbonylthiophene-3-yl)aminomalonates and (2-cyano-5-aminothiophene-3-yl)carbamates with the preparative yields of up to 67%. It

• . The same reaction with 2a in toluene solution (reflux at 110 °C) instead of benzene lead to a decrease of the yield of thiophene 3a (to 38%) in favour of thiophene 4a (42%, Table 1, entry 2). However, even under these fairly severe conditions, it took from 3 to 6 h to achieve a complete conversion of

• of thiophene 4a (up to 32%), though the total yield of the main reaction products 3a + 4a therewith decreased to 53% (Table 1, entry 5). Replacing diazomalonate 2a by diethyl diazomalonate (2b) did not essentially change the yields of the main products, 3a’ and 4a’ (44 and 20%, respectively; Table 1

Structure–property relationships and third-order nonlinearities in diketopyrrolopyrrole based D–π–A–π–D molecules

• Jan Podlesný,
• Lenka Dokládalová,
• Oldřich Pytela,
• Adam Urbanec,
• Milan Klikar,
• Numan Almonasy,
• Tomáš Mikysek,
• Jaroslav Jedryka,
• Iwan V. Kityk and
• Filip Bureš

Beilstein J. Org. Chem. 2017, 13, 2374–2384, doi:10.3762/bjoc.13.235

• -photon absorbers (2PA). In this respect, the central DPP bicyclic lactam is often decorated with electron donors such as alkoxy- or dialkylamino groups [11][12], triphenylamine [13][14], heterocyclic carbazole [15], thiophene [16][17], furan [18], and organometallic ferrocene [19]. 2PA-active DPPs were

• report herein the systematic modification of the 3,6-dithienyl-2,5-dihydropyrrolo[3,4-c]pyrrole-1,4-dione central acceptor with N,N-dimethylanilino (DMA), methoxyphenyl, thiophene, methoxythiophene, and ferrocene peripheral electron donors (Figure 1). Fundamental properties of D–π–A–π–D chromophores 1–5

• and its final cross-coupling reactions (Scheme 1). The construction of the DPP central scaffold 6 was accomplished by a well-known reaction between thiophene-2-carbonitrile and dimethyl succinate in the presence of sodium tert-amylalcoholate generated in situ [32]. The reaction provided 6 with a high

Dialkyl dicyanofumarates and dicyanomaleates as versatile building blocks for synthetic organic chemistry and mechanistic studies

• Grzegorz Mlostoń and
• Heinz Heimgartner

Beilstein J. Org. Chem. 2017, 13, 2235–2251, doi:10.3762/bjoc.13.221

• substituents were formed. Polycyclic products 35 were prepared through a concerted [4 + 2]-cycloaddition of E-1a with thiophene-functionalized fulvenes 36 [42] (Scheme 12). These cycloadducts are reported to undergo reversible intramolecular photocyclization to give products of type 37. The formation of the

• thiophene derived sulfur ylide 12. Cyclopropanation of dimethyl dicyanofumarate (E-1b) through a stepwise reaction with the in situ generated thiocarbonyl S-isopropanide 16a. The [2 + 2]-cycloadditions of dimethyl dicyanofumarate (E-1b) with electron-rich ethylenes 20 and 22. The [2 + 2]-cycloaddition of

Phosphonic acid: preparation and applications

• Charlotte M. Sevrain,
• Mathieu Berchel,
• Hélène Couthon and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2017, 13, 2186–2213, doi:10.3762/bjoc.13.219

• the transformation of phosphonates under acidic conditions. As an illustration, the thiophene diphosphonic acid 49 [173], the pyridine oxide 50 [179], the furane phosphonic acid 51 [174], the bipyridine bis thiophene phosphonic acid 52 [180] or the α-aminophosphonic acid 53 that was assessed as

Mechanochemical synthesis of small organic molecules

• Tapas Kumar Achar,
• Anima Bose and
• Prasenjit Mal

Beilstein J. Org. Chem. 2017, 13, 1907–1931, doi:10.3762/bjoc.13.186

• ]. Mechanochemical methods of the Mannich reaction, Paal–Knorr synthesis, Bigineli reaction, Hantzsch reaction, and syntheses of substituted pyran, thiophene, isoquinoline derivatives, etc. are also reported [104][107][112][113]. Isocyanide-based multi-component reactions are also well known [114][115]. Recently, in

• the sole products. Contrastingly, in the solution of acetonitrile imines of benzaldehyde and amines were formed preferably. Different aromatic or heteroaromatic aldehydes including thiophene carboxaldehyde, pyridine carboxaldehyde and cyclohexyl carboxaldehyde as well as various amines like morpholine

Synthesis of benzothiophene and indole derivatives through metal-free propargyl–allene rearrangement and allyl migration

• Jinzhong Yao,
• Yajie Xie,
• Lianpeng Zhang,
• Yujin Li and
• Hongwei Zhou

Beilstein J. Org. Chem. 2017, 13, 1866–1870, doi:10.3762/bjoc.13.181

• heterocycles are not well-documented [30][31]. Recently, our group explored the utilization of β-sulfonium carbanions for the preparation of thiophene derivatives [19]. Alkynes were treated with acyl chloride under Sonogashira reaction conditions and the expected β-sulfonium carbanions were obtained in a one

The chemistry and biology of mycolactones

• Matthias Gehringer and
• Karl-Heinz Altmann

Beilstein J. Org. Chem. 2017, 13, 1596–1660, doi:10.3762/bjoc.13.159

New electroactive asymmetrical chalcones and therefrom derived 2-amino- / 2-(1H-pyrrol-1-yl)pyrimidines, containing an N-[ω-(4-methoxyphenoxy)alkyl]carbazole fragment: synthesis, optical and electrochemical properties

• Daria G. Selivanova,
• Alexei A. Gorbunov,
• Olga A. Mayorova,
• Alexander N. Vasyanin,
• Igor V. Lunegov,
• Elena V. Shklyaeva and
• Georgii G. Abashev

Beilstein J. Org. Chem. 2017, 13, 1583–1595, doi:10.3762/bjoc.13.158

• linked with a central pyrimidine core and another one is linked by a rigid thiophene cycle as a π-conjugated bridge. We have applied a usual synthetic protocol which includes eight successive steps: O-alkylation of 4-methoxyphenol (1), N-alkylation of carbazole (2), formylation or acetylation of a

• resulted N-alkyl carbazole (3), two-staged incorporation of thiophene moiety into obtained methyl ketone (4,5), condensation of the prepared aldehyde and methylketone (6), cyclization of thus prepared chalcone into 4,6-disubstituted 2-aminopyrimidine (7) and preparation of a target product – 4.6

• -carbazoles 3a,b were obtained via acetylation of the same carbazoles 1a,b [20]. The presence of an acetyl group in the resulted compounds 3a and 3b gives the opportunity to extend their conjugation chain via incorporation of an thiophene moiety with the help of a Vilsmeier–Haack–Arnold reaction. The reaction

Molecular-level architectural design using benzothiadiazole-based polymers for photovoltaic applications

• Vinila N. Viswanathan,
• Arun D. Rao,
• Upendra K. Pandey,
• Arul Varman Kesavan and
• Praveen C. Ramamurthy

Beilstein J. Org. Chem. 2017, 13, 863–873, doi:10.3762/bjoc.13.87

• significant role in increasing the efficiency for OPVs [30][31]. However, fused π-bridges (such as thienothiophene) having a larger molecular structure and higher degree of conjugation are less explored with respect to thiophene and furan spacers. Thienothiophene ensures a highly delocalized electron system

• and higher charge carrier mobility due to its rigid and coplanar fused structure. Also, some thienothiophene-based polymers show a noticeable bathochromic shift in their absorption spectra in comparison with thiophene-substituted polymers [32][33][34]. Herein, keeping all these criteria in mind, we

• and donor, respectively [35][36]. The acceptor motif was further coupled with thiophene to increase the conjugation length and absorption. The same acceptor moiety was substituted with fluorine and the effect of this substitution on the polymeric and photovoltaic properties was studied. Furthermore

Isoxazole derivatives as new nitric oxide elicitors in plants

• Anca Oancea,
• Emilian Georgescu,
• Florentina Georgescu,
• Alina Nicolescu,
• Elena Iulia Oprita,
• Catalina Tudora,
• Lucian Vladulescu,
• Marius-Constantin Vladulescu,
• Florin Oancea and
• Calin Deleanu

Beilstein J. Org. Chem. 2017, 13, 659–664, doi:10.3762/bjoc.13.65

• procedures towards isoxazole derivatives were developed [36][37]. As part of our continued efforts to develop simple synthetic routes towards bioactive heterocyclic compounds [38][39][40][41][42][43], we report here the synthesis of several 3,5-isoxazole derivatives, bearing benzo[1,3]dioxole and thiophene

• ]. The thiophene is a core system of a large number of bioactive molecules such as antineoplastic agents [49], non-steroidal anti-inflammatory drugs [50] or compounds with antibacterial activities against several Gram-positive strains [51]. Thus, 3,5-disubstituted isoxazole derivatives were obtained by

Synthesis and optical properties of new 5'-aryl-substituted 2,5-bis(3-decyl-2,2'-bithiophen-5-yl)-1,3,4-oxadiazoles

• Anastasia S. Kostyuchenko,
• Tatyana Yu. Zheleznova,
• Anton J. Stasyuk,
• Aleksandra Kurowska,
• Wojciech Domagala,
• Adam Pron and
• Alexander S. Fisyuk

Beilstein J. Org. Chem. 2017, 13, 313–322, doi:10.3762/bjoc.13.34

• ) The ethyl esters of 2,2'-bithiophenes 7 having no (7a), an alkyl (7b), or a thienyl (7c) substituent in the C-5' position can be easily obtained by this method. On the other hand, the substitution of the thiophene ring with phenyl or fused aromatic rings is much more challenging and requires the

• between 389 and 409 nm, ascribed to the π–π* transition. A comparison of the absorption spectra of 15b and 15c–g indicates that the presence of a thiophene ring or carboaromatic substituents at the C-5' position in the 2,5-bis(2,2'-bithiophen-5-yl)-1,3,4-oxadiazole leads to a slight bathochromic shift of

• to the π–π* transition for the studied thiophene, phenyl, naphthalene and anthracene-substituted derivatives, shows a small hypsochromic shift with increasing spatial volume of the substituent R. This observation is in a full accordance with the aforementioned relationship of the molecule planarity

The reductive decyanation reaction: an overview and recent developments

• Jean-Marc R. Mattalia

Beilstein J. Org. Chem. 2017, 13, 267–284, doi:10.3762/bjoc.13.30

• less reactive nitriles, the C–CN bond cleavage usually requires hydrogen under pressure and high temperatures [86]. Tao et al. reported the decyanation of 2-cyanobenzo[b]thiophene using hydrogen and Pd, Pt/TiO2 or Pd/TiO2-Cu as catalyst at 200–300 °C with yields varying from 79 to 90% (Scheme 14) [87

• both methods (34h) but, with the bromo counterpart, dehalogenation also occurs. 2-Cyanothiophene results in quantitative yield of thiophene 60 with both methods but cyanopyridines are not converted, probably due to the coordination abilities of the pyridine. Finally, decanenitrile is decyanated with

• reduction by NaH [81]. Reductive decyanation catalyzed by nickel nanoparticles. Yields are given in weight % from GC–MS data [85]. Decyanation of 2-cyanobenzo[b]thiophene [87]. Simplified pathways involved in transition-metal-promoted reductive decyanations [93][95]. Fe-catalyzed reductive decyanation

Regiochemistry of cyclocondensation reactions in the synthesis of polyazaheterocycles

• Patrick T. Campos,
• Leticia V. Rodrigues,
• Andrei L. Belladona,
• Caroline R. Bender,
• Juliana S. Bitencurt,
• Fernanda A. Rosa,
• Davi F. Back,
• Helio G. Bonacorso,
• Nilo Zanatta,
• Clarissa P. Frizzo and
• Marcos A. P. Martins

Beilstein J. Org. Chem. 2017, 13, 257–266, doi:10.3762/bjoc.13.29

• , thiophene-2-glyoxylic acid, and N-(2-amino-4-nitrophenyl)acetamide, in accordance with the mechanism proposed in this work. To rationalize why the cyclization reaction between the amidines 8g,h and the α-ketoester did not occur, the HOMO coefficient and charge densities for the nitrogens of the amidine were

A versatile route to polythiophenes with functional pendant groups using alkyne chemistry

• Xiao Huang,
• Li Yang,
• Rikard Emanuelsson,
• Jonas Bergquist,
• Maria Strømme,
• Martin Sjödin and
• Adolf Gogoll

Beilstein J. Org. Chem. 2016, 12, 2682–2688, doi:10.3762/bjoc.12.265

• polymers; polythiophene; Sonogashira coupling; thiophene; Introduction Currently organic conjugated polymers are attracting considerable interest for various applications in plastic electronics. In particular, poly(3,4-ethylenedioxythiophene) (PEDOT) [1] and its derivatives [2][3][4][5][6][7] play an

• , these functionalizations require only readily available starting materials. A related concept, i.e., attachment of a terminal alkyne moiety to the polymerizable thiophene derivative ProDOT, an EDOT analogue, and its utilization for “click“ chemistry has been reported [28]. However, this involved an

• phthalimide-EDOT derivative 13 failed to polymerize. A plausible reason could be an interference of the electron rich aromatic moieties with the thiophene radical cations formed during polymerization, in analogy to previous suggestions from Bäuerle et al. for triazolomethyl-substituted EDOT. Post

Effects of solvent additive on “s-shaped” curves in solution-processed small molecule solar cells

• John A. Love,
• Shu-Hua Chou,
• Ye Huang,
• Guilllermo C. Bazan and
• Thuc-Quyen Nguyen

Beilstein J. Org. Chem. 2016, 12, 2543–2555, doi:10.3762/bjoc.12.249

• -silolo[3,2-b]thiophene-2,2′-diyl)bis(6-fluoro-4-(5′-hexyl-[2,2′-bithiophene]-5-yl)benzo[c][1,2,5]thiadiazole, p-SIDT(FBTTh2)2, (Figure 1), we have modified the conjugated backbone to include electron-withdrawing octyl cyanoacetate (CA8) end groups, essentially forming an “A1–D1–A2–D2–A2–D1–A1” molecular

• skeleton, benzo[1,2-b:4,5-b]bis(4,4′-dihexyl-4H-silolo[3,2-b]thiophene-2,2′-diyl)bis(6-fluoro-4-((E)-octyl-3-(5-thiophen-2-yl)-2-cyanoacrylate]-5-yl)benzo[c][1,2,5]thiadiazole, p-SIDT(FBTThCA8)2. We will show that this molecular substitution did indeed significantly reduce the bandgap while maintaining

A new paradigm for designing ring construction strategies for green organic synthesis: implications for the discovery of multicomponent reactions to build molecules containing a single ring

• John Andraos

Beilstein J. Org. Chem. 2016, 12, 2420–2442, doi:10.3762/bjoc.12.236

• dihydropyridine, hydantoin, imidazole, indole, isoquinoline, isoxazole, oxazole, 4H-pyran, pyrazine, pyridazine, pyridine, pyridinone, pyrimidine, pyrimidone, pyrrole, 3H-quinazolin-4-one, quinoline, 1H-quinolin-4-one, and thiophene. For heterocycles that are composed of a fused aromatic ring, such as

High performance p-type molecular electron donors for OPV applications via alkylthiophene catenation chromophore extension

• Paul B. Geraghty,
• Calvin Lee,
• Jegadesan Subbiah,
• Wallace W. H. Wong,
• James L. Banal,
• Mohammed A. Jameel,
• Trevor A. Smith and
• David J. Jones

Beilstein J. Org. Chem. 2016, 12, 2298–2314, doi:10.3762/bjoc.12.223

• , Melbourne, Australia 10.3762/bjoc.12.223 Abstract The synthesis of key 4-alkyl-substituted 5-(trimethylsilyl)thiophene-2-boronic acid pinacol esters 3 allowed a simplified alkylthiophene catenation process to access bis-, ter-, quater-, and quinquethiophene π-bridges for the synthesis of acceptor–π-bridge

• recently used side-chain engineering, through regioregular placement of hexyl side chains on a thiophene π-bridge [13], to generate a MM with a planar core structure and enhanced device performance, up to 9.3% power conversion efficiency (PCE) [14]. This material, built from three key building blocks

• -bromothiophene-2-carboxaldehyde to generate the bithiophene 4, Scheme 3. It has previously been reported that direct coupling of 2-(trimethylsilyl)thiophene with aryl halides proceeds in good yield with protodesilylation being the major side reaction under the reaction conditions, even at short reaction times

Regiocontroled Pd-catalysed C5-arylation of 3-substituted thiophene derivatives using a bromo-substituent as blocking group

• Mariem Brahim,
• Hamed Ben Ammar,
• Jean-François Soulé and
• Henri Doucet

Beilstein J. Org. Chem. 2016, 12, 2197–2203, doi:10.3762/bjoc.12.210

• “green” access to arylated thiophene derivatives as it reduces the number of steps to prepare these compounds and also the formation of wastes. Keywords: aryl bromides; C–H bond activation; catalysis; direct arylation; palladium; thiophenes; Introduction Thiophene derivatives bearing aryl substituents

• -substituted thiophene derivatives is an important topic in sustainable chemistry [4]. Stille or Suzuki palladium-catalysed coupling reactions [5][6][7][8][9][10] are some of the most efficient methods for the preparation of 5-arylated 3-substituted thiophenes [11][12][13][14]. However, before these coupling

• reactions can be performed, an organometallic compound must be synthesized. In 1990, Ohta and co-workers described the Pd-catalysed direct arylation of thiophene derivatives by coupling reaction with aryl halides [15][16]. This is a highly powerful method for a greener access to a very broad range of

Comparing blends and blocks: Synthesis of partially fluorinated diblock polythiophene copolymers to investigate the thermal stability of optical and morphological properties

• Pierre Boufflet,
• Sebastian Wood,
• Jessica Wade,
• Zhuping Fei,
• Ji-Seon Kim and
• Martin Heeney

Beilstein J. Org. Chem. 2016, 12, 2150–2163, doi:10.3762/bjoc.12.205

• KCTP using a method analogous to that used for thiophene-selenophene block copolymers [26]. Due to the much lower solubility of F-P3OT compared to P3OT, the more soluble P3OT block was grown first from the activated monomer 2, followed by the addition of 4 to the P3OT macroinitiator. Relative block

• washing. The true relative block lengths were calculated from the 1H NMR spectra of the purified polymers, based on the relative intensities of the signals assigned to the methylene protons adjacent to the thiophene ring (Figure 2). Due to the reduced solubility of the polymers, the spectra were recorded

• -rich polymer chains is found to be substantially different to the corresponding blend at temperatures below the thermal transition. While the intensity of the thiophene C=C stretching mode steadily decreases with increasing temperature in the case of the blend, it remains constant in the block

Thiophene-forming one-pot synthesis of three thienyl-bridged oligophenothiazines and their electronic properties

• Dominik Urselmann,
• Konstantin Deilhof,
• Bernhard Mayer and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2016, 12, 2055–2064, doi:10.3762/bjoc.12.194

• electronics [37][38][39][40]. In comparison to thiophene, phenothiazine, a tricyclic dibenzo-1,4-thiazine, possesses a significantly lower oxidation potential, similar to aniline. However, phenothiazine derivatives form stable deeply colored radical cations with perfect Nernstian reversibility [41][42][43][44

• to form self-assembled monolayers on gold [69][70][71] as well as on zinc and iron oxide surfaces [72]. Conceptually, thienyl-bridged oligophenothiazines can be considered as a novel type of structurally well-defined electron-rich oligophenothiazine–thiophene hybrids (Figure 1). Thereby, the strong

• luminescent 2,5-di(hetero)arylfurans [77] could open a highly convergent thiophene forming approach to the proposed title compounds. Here, we report the pseudo five-component synthesis of three thienyl-bridged oligophenothiazines by a one-pot Sonogashira–Glaser cyclization sequence and the electronic

Application of heterocyclic aldehydes as components in Ugi–Smiles couplings

• Katelynn M. Mason,
• Michael S. Meyers,
• Abbie M. Fox and
• Sarah B. Luesse

Beilstein J. Org. Chem. 2016, 12, 2032–2037, doi:10.3762/bjoc.12.191

• barriers associated with the use of heterocyclic aldehydes, compared to simple aliphatic aldehydes, providing access to Ugi–Smiles adducts. The use of a sulfur-based heterocyclic aldehyde, thiophene-2-carboxaldehyde, provided the Ugi–Smiles adducts in low yields (Scheme 3). While such thienyl-substituted

• observed for 2- and 3-furaldehyde with a variety of amine components. In the presence of a competent dienophile, the Ugi–Smiles coupling is followed by a facile intramolecular Diels–Alder cycloaddition to generate oxatricyclic N-arylepoxyisoindolines. Initial results with thiophene-2-carboxaldehyde show

Effect of the π-conjugation length on the properties and photovoltaic performance of A–π–D–π–A type oligothiophenes with a 4,8-bis(thienyl)benzo[1,2-b:4,5-b′]dithiophene core

• Ni Yin,
• Lilei Wang,
• Yi Lin,
• Jinduo Yi,
• Lingpeng Yan,
• Junyan Dou,
• Hai-Bo Yang,
• Xin Zhao and
• Chang-Qi Ma

Beilstein J. Org. Chem. 2016, 12, 1788–1797, doi:10.3762/bjoc.12.169

• characterization of BDT derivatives based on oligothiophene π-bridges with more than three thiophene units [27], where symmetric quater- and quinquethiophenes were used as the π-conjugation bridge. Surprisingly, the quaterthiophene-bridged compound showed the worst photovoltaic performance when blending with a

Rearrangements of organic peroxides and related processes

• Ivan A. Yaremenko,
• Vera A. Vil’,
• Dmitry V. Demchuk and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2016, 12, 1647–1748, doi:10.3762/bjoc.12.162

• synthesis of various heterocyclic systems, such as furan, thiophene, and pyrrole derivatives. The reaction of unsymmetrical epoxy dioxanes 290a–d with triethylamine is accompanied by the 1,2-dioxane-ring opening to form 4-hydroxy-2,3-epoxy ketones 291a–d in high yields. The base catalysis involves the

Synthesis and characterization of benzodithiophene and benzotriazole-based polymers for photovoltaic applications

• Desta Gedefaw,
• Marta Tessarolo,
• Margherita Bolognesi,
• Mario Prosa,
• Renee Kroon,
• Wenliu Zhuang,
• Patrik Henriksson,
• Kim Bini,
• Ergang Wang,
• Michele Muccini,
• Mirko Seri and
• Mats R. Andersson

Beilstein J. Org. Chem. 2016, 12, 1629–1637, doi:10.3762/bjoc.12.160

• -conjugation from the backbone to the lateral substituent (2D π-conjugated systems), thus leading to a bandgap reduction and higher charge carrier mobilities [15][16][17][18]. On the other hand, the Tz moiety, usually sandwiched between adjacent thiophene spacers to limit the inter-monomers steric hindrance

• PTzBDT-2 (Scheme 1), based on Tz and BDT moieties. The Tz ring was substituted with an asymmetrically branched alkyl side chain and sandwiched between two thiophene rings. The chemical structure of the Tz based monomer was made to be the same in both polymers for the comparative study. On the other hand

• polymers were determined using size exclusion chromatography and the results are summarized in Table 1. PTzBDT-2 showed a higher molecular weight (Mn = 41.7 kDa) due to the two n-hexyl solubilizing alkyl side chains per thiophene attached to the BDT core unit. On the contrary, PTzBDT-1 with a relatively