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A convenient two-step, one-pot synthesis of oligo(arylene–ethynylene) (OAE) type molecular wires in yields of up to 70% via in situ desilylation of protected bis(alkynes) Me3SiC≡CArC≡CSiMe3 (Ar = 2,5-thienyl, 1,4-naphthylene, 9,10-anthrylene) and subsequent Sonogashira cross-coupling with S -(4-iodophenyl) ethanethiolate, 4-iodothioanisole, or 5-bromo-3,3-dimethyl-2,3-dihydrobenzo[ b ]thiophene is described. The in situ desilylation avoids the manipulation of the sensitive terminal dialkynes (HC≡CArC≡CH), whilst the general approach presented has some advantages over alternative synthetic strategies based on coupling of aryl dihalides (XArX) by avoiding the multi-step preparation and purification of the terminal alkynes S -(4-ethynylphenyl) ethanethiolate, 4-ethynylthioanisole and 5-ethynyl 3,3-dimethyl-2,3-dihydrobenzo[ b ]thiophene. The molecular conductance of the resulting thiolate or thioether functionalised OAE molecular wires has been determined using scanning tunneling microscope break junction (STM-BJ) methods. The trends in molecular conductance do not track simply with the degree of aromaticity of the molecular core despite the rather similar molecular lengths. Rather, the STM-BJ data are better correlated with the nature of the anchor group, highlighting the important role of electrode–molecule coupling on electron transport in a molecular junction. The experimental conductance data are in good agreement with recently described quantum circuit rules, further highlighting the potential for these relationships to be used as predictive tools in molecular electronics research. A two-step, one-pot synthesis of oligo(arylene–ethynylene) molecular wires that avoids manipulation of sensitive terminal bis(alkynes) is described. Trends in molecular conductance do not track with the molecular core aromaticity, but correlate with the recently described quantum circuit rules and associated bridge and anchor parameters. [ABSTRACT FROM AUTHOR]

A convenient two-step, one-pot synthesis of oligo(arylene–ethynylene) (OAE) type molecular wires in yields of up to 70% via in situ desilylation of protected bis(alkynes) Me3SiC≡CArC≡CSiMe3 (Ar = 2,5-thienyl, 1,4-naphthylene, 9,10-anthrylene) and subsequent Sonogashira cross-coupling with S -(4-iodophenyl) ethanethiolate, 4-iodothioanisole, or 5-bromo-3,3-dimethyl-2,3-dihydrobenzo[ b ]thiophene is described. The in situ desilylation avoids the manipulation of the sensitive terminal dialkynes (HC≡CArC≡CH), whilst the general approach presented has some advantages over alternative synthetic strategies based on coupling of aryl dihalides (XArX) by avoiding the multi-step preparation and purification of the terminal alkynes S -(4-ethynylphenyl) ethanethiolate, 4-ethynylthioanisole and 5-ethynyl 3,3-dimethyl-2,3-dihydrobenzo[ b ]thiophene. The molecular conductance of the resulting thiolate or thioether functionalised OAE molecular wires has been determined using scanning tunneling microscope break junction (STM-BJ) methods. The trends in molecular conductance do not track simply with the degree of aromaticity of the molecular core despite the rather similar molecular lengths. Rather, the STM-BJ data are better correlated with the nature of the anchor group, highlighting the important role of electrode–molecule coupling on electron transport in a molecular junction. The experimental conductance data are in good agreement with recently described quantum circuit rules, further highlighting the potential for these relationships to be used as predictive tools in molecular electronics research. A two-step, one-pot synthesis of oligo(arylene–ethynylene) molecular wires that avoids manipulation of sensitive terminal bis(alkynes) is described. Trends in molecular conductance do not track with the molecular core aromaticity, but correlate with the recently described quantum circuit rules and associated bridge and anchor parameters. [ABSTRACT FROM AUTHOR]

An efficient route is developed to synthesize a series of platinum‐co‐poly(p‐phenylenebutadiynylene)s (Pt‐co‐PPBs) polymers by stoichiometric mixing of poly(p‐phenylenebutadiynylene)s (PPBs) and platinum bis‐phosphine dichlorides. This synthetic route involves two steps; first, oxidative coupling of diterminal phenyleneethynylenes (PEs) gives low‐molecular‐weight PPBs oligomers HCC(Ph(OR)2 CCCC)n Ph(OR)2 CCH (R = C4H91, R = C8H172, R = C12H253) (Mn = 1000–3000, degrees of polymerization, Pn(Mn) = 4–6), which have bifunctional alkynyl end groups, and in the second step, these organic oligomers are allowed to react with trans‐[(PnBu3)2PtCl2] to form newly designed Pt‐co‐PPBs (R = C4H94, R = C8H175, R = C12H256) polymers. The yield of 4–6 varies from good (63%) to high (76%) with high molecular weights (Mn) ranging from 52 738 to 74 212, and this methodology tolerates different alkoxy substituted PPBs. These new organometallic polymers contain platinum to phenylenebutadiynylene (PB) ratio of 1:4 to 1:6 and are solution processable. Polymer 4 displays fluorescence at room temperature and fluorescence and phosphorescence at low temperature in thin film, which would be useful for studying the triplet emission in these polymers. [ABSTRACT FROM AUTHOR]

The control of thermal stability of polyaniline (PANI) nanofibers is reported by systematically varying the loadings of CaO in the range from 0.005 g to 1.0 g. It was found to gradually increase the yield of synthesized PANI nanofibers with the increase of CaO addition. The highest yield, 1.103 g was obtained for 1.00 g loading of CaO. The incorporation of CaO into PANI matrix was revealed by energy-dispersive X-ray spectroscopy (EDX). Thermogravimetric analysis (TGA) data showed that the thermal stability of PANI nanofibers was greatly improved when CaO was added to the system. 1.00 g loading of CaO is favorable to obtain comparatively more thermally stable PANI. The degradation of PANI chains started at 330 °C for the PANI-CaO composites obtained at 1.00 g CaO addition, which is the highest temperature compared to PANI and the samples synthesized at other amount of CaO loadings. Furthermore, the increasing trend of thermal stability was observed with the increasing of CaO loading. [ABSTRACT FROM AUTHOR]

Whilst 2- or 5-OMe groups on the bridging phenylene ring in [{Cp*(dppe)RuC≡C} 2 (μ-1,3-C 6 H 4 )] + have little influence on the electronic structure of this weakly coupled mixed-valence complex, a 4-OMe substituent enhances ground state electron delocalization, and increases the intensity of the IVCT transition. Vibrational frequency and TDDFT calculations (LH20t-D3(BJ), def2-SVP, COSMO (CH 2 Cl 2 )) on ([{Cp*(dppe)RuC≡C} 2 (μ-1,3-C 6 H 3 -n-OMe)] + (n=2, 4, 5) models are in excellent agreement with the experimental results. The stronger ground state coupling is attributed to the change in composition of the β-HOSO brought about by the 4-OMe group, which is ortho or para to each of the metal fragments. The intensity of the IVCT transition increases with the greater overlap of the β-HOSO and β-LUSO, whilst the relative phases of the β-HOSO and β-LUSO in the 4-OMe substituted complex are consistent with predictions of constructive quantum interference from molecular circuit rules., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)