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An environmentally friendly and sustainable approach was adopted to produce a molecularly imprinted polymer (MIP) via electropolymerization, with remarkable electrochemical sensing properties, tested in tyrosine (tyr) detection. The 2,2′-bis(2,2′-bithiophene-5-yl)-3,3′-bithianaphtene (BT2-T4) was chosen as functional monomer and MIP electrosynthesis was carried out via cyclic voltammetry on low-volume (20 μL) screen-printed carbon electrodes (C-SPE) in ionic liquid 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ((BMIM) TFSI). An easy and rapid washing treatment allowed us to obtain the resulting MIP film, directly used for tyr electrochemical detection, carried out amperometrically. The sensor showed a linear response in the concentration range of 15–200 μM, with LOD of 1.04 µM, LOQ of 3.17 μM and good performance in selectivity, stability, and reproducibility. Tyrosine amperometric detection was also carried out in human plasma, resulting in a satisfactory recovery estimation. The work represents the first use of BT2-T4 as a functional monomer for the production of a molecularly imprinted polymer, with a green approach afforded by using a few microliters of a room temperature ionic liquid as an alternative to common organic solvents on screen-printed carbon electrodes, resulting in a valuable system that meets the green chemistry guidelines, which is today an essential criterion in both research and application field. [ABSTRACT FROM AUTHOR]

A p-type thermoelectric conjugated polymer based on indacenodithiophene and benzothiadiazole is designed and synthesized by replacing normal aliphatic side chains (P1) with conjugated aromatic benzene substituents (P2). The introduced bulky substituent on P2 is detrimental to form the intensified packing of polymers, therefore, it hinders the efficient transporting of the charge carriers, eventually resulting in a lower conductivity compared to that of the polymers bearing aliphatic side chains (P1). These results reveal that the modification of side chains on conjugated polymers is crucial to rationally designed thermoelectric polymers with high performance. [ABSTRACT FROM AUTHOR]

The synthesis of FcC(O)CH(R)C(O)Fc (Fc = Fe(η5-C5H4)(η5-C5H5); R = H, 5; nBu, 7; CH2CH2(OCH2CH2)2OMe, 9), [M(κ2O,O′-FcC(O)CHC(O)Fc)n] (M = Ti, n = 3, 10; M = Fe, n = 3, 11; M = BF2, n = 1, 12), and 1-R′-3,5-Fc2-cC3HN2 (R′ = H, 13; Me, 14; Ph, 15) is discussed. The solid-state structures of 5, 7, 9, 12, 13, 15, and 16 ([TiCl2(κ2O,O′-PhC(O)CHC(O)Ph)2]) show that 7 and 9 exist in their β-diketo form. Compound 13 crystallizes as a tetramer based on a hydrogen bond pattern, including one central water molecule. The electrochemical behavior of 5–7 and 9–16 was studied by cyclic and square-wave voltammetry, showing that the ferrocenyls can separately be oxidized reversibly between −50 and 750 mV (5–7, 9, 12–15: two Fc-related events; 10, 11: six events, being partially superimposed). For complex 10, Ti-centered reversible redox processes appear at −985 (TiII/TiIII) and −520 mV (TiIII/TiIV). Spectro-electrochemical UV-Vis/NIR measurements were carried out on 5, 6, and 12, whereby only 12 showed an IVCT (intervalence charge-transfer) band of considerable strength (νmax = 6250 cm−1, Δν½ = 4725 cm−1, εmax = 240 L·mol−1·cm−1), due to the rigid C3O2B cycle, enlarging the coupling strength between the Fc groups. [ABSTRACT FROM AUTHOR]

Direct (hetero)arylation (DHA) is playing a key role in improving the efficiency and atom economy of C–C cross coupling reactions, so has impacts in pharmaceutical and materials chemistry. Current research focuses on further improving the generality, efficiency and selectivity of the method through careful tuning of the reaction conditions and the catalytic system. Comparatively fewer studies are dedicated to the replacement of the high-boiling-point organic solvents dominating the field and affecting the overall sustainability of the method. We show herein that the use of a 9:1 v/v emulsion of an aqueous Kolliphor 2 wt% solution while having toluene as the reaction medium enables the preparation of relevant examples of thiophene-containing π-conjugated building blocks in high yield and purity. [ABSTRACT FROM AUTHOR]