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Some new pyridyl alcohols with the cis-bicyclo[3.3.0]octane scaffold were synthesized and used as chiral ligands for the enantioselective addition of diethylzinc to aldehydes. Ligands 4 were found to be far superior to the C2-symmetric ligands 2 in terms of enantioselectivities. Quantitative yields and enantiomeric excesses of up to 92% were obtained when the ligand 4 was used. The carbonyl function in 4 proved to be beneficial for the high enantioselectivities in the addition of diethylzinc to aldehydes. Conversion of the carbonyl group into oxime or oxime ether group led to a sort of more active ligands, which catalyzed the same reaction with rate acceleration. [Copyright &y& Elsevier]

A new category of β-amino alcohols with a bicyclo[3.3.0]octane scaffold has been synthesized and used in the direct asymmetric nitroaldol reaction (Henry reaction). Up to 74% ee was obtained with the addition of nitromethane to relatively bulky aldehydes. [Copyright &y& Elsevier]

Amino alcohols with the bicyclo[3.3.0]octane framework were synthesized, characterized and used as chiral ligands for the addition of diethylzinc to aldehydes. Quantitative yields and enantiomeric excesses of up to 92% were obtained in the ethylation reactions. [Copyright &y& Elsevier]

Remarkable progress has been made in perovskite solar cells (PSCs) recently. However, the defects present in the perovskite layer act as non-radiative recombination centers to decrease the stability and restrict the further performance improvement of the device. We report herein a sulfur-rich two-dimensional small molecule, SMe-TATPyr, as a bifunctional layer to efficiently passivate the surface defects of perovskite and facilitate the hole transfer at the perovskite/spiro-OMeTAD interface. X-ray photoelectron spectroscopy analyses show that the sulfur atoms of SMe-TATPyr can passivate the uncoordinated Pb2+ defects and suppress the Pb0 defect formation as Lewis bases. As a result, the power conversion efficiency of PSCs is distinctly increased from 20.4% to 22.3%. Moreover, this simple interfacial modification could effectively enhance the stability of unencapsulated PSCs to retain 95% of the initial efficiency after storage for 1500 h at ambient conditions, in contrast to 70% efficiency retention of the device without SMe-TATPyr under the same conditions. ga1 A sulfur-rich two-dimensional small molecule, SMe-TATPyr, has been used as a bifunctional interlayer to efficiently passivate the surface defects of perovskite and facilitate the hole transfer at the perovskite/spiro-OMeTAD interface. The SMe-TATPyr-treated perovskite solar cells demonstrate a remarkable efficiency of 22.3%, along with 95% retention of the initial efficiency under storage for 1500 h at ambient conditions. • A sulfur-rich small molecule is designed as a bifunctional reagent for interfacial defect passivation and hole transfer. • The use of the interfacial layer leads to the efficiency enhancement from 20.4% to 22.3%. • The effect of interfacial defect passivation is fully supported by different physical measurements. [ABSTRACT FROM AUTHOR]

A novel multi-functional interface material (TAAPyr) is first developed as a defect passivation layer and a protect layer against moisture for PSCs application. Consequently, the efficiency of TAAPyr-based device can increase form 20.37% to 22.45%, with an unencapsulated device retaining 90% of its initial efficiency after storage for 600h at ∼65% humidity. [Display omitted] • A hydrophobic multi-functional interface material is developed for PSCs application. • TAAPyr-treated PSCs shows an improvement in efficiency from 20.37% to 22.45%. • Device long-term stability has greatly been enhanced. Surface treatment of perovskite films with interface materials is an effective strategy to resolve trap-mediated nonradiative recombination toward high efficiency and stability of perovskite solar cells (PSCs). However, interface materials for multi-functional treatment have been rarely investigated in PSCs. In this work, a novel pyrene-based organic material (TAAPyr) is first introduced as a defect passivation layer and a protect layer against moisture for PSCs application. With the TAAPyr interfacial modification, both perovskite surface defects and nonradiative recombination are effectively decreased as well as the carrier transport in device is also enhanced, As a consequence, the best power conversion efficiencies (PCE) up to 22.45% for TAAPyr-based device was obtained, clearly outperforming the control one (20.37%). Moreover, it was found that the π-conjugated TAAPyr can promote intermolecular face-to-face stacking on the surface perovskite film, which is favorable to making the perovskite surface more hydrophobic and consequently enhance PSCs long-term stability. The un-encapsulated PSCs can retain 92% of the initial PCE after storage for 600 h at ∼65% RH, in comparison with 64% efficiency retention of the device without TAAPyr under the same conditions. This work presents a new strategy to enhance the efficiency and stability of PSCs by multi-functional π–conjugated passivator. [ABSTRACT FROM AUTHOR]

Abstract: The reductive co-electropolymerization of vinyl-substituted ruthenium complexes 2(PF6) and 3(PF6)2 at ITO glass electrodes have afforded adherent metallopolymeric films, where complex 2(PF6) contains a dipicolylamine (DPA) unit as the ion recognition site and 3(PF6)2 is a ruthenium monomer without DPA. The resulting thin films can selectively detect Cu2+ at the solid-liquid interface on the basis of color, absorption, and electrochemical changes. By using EDTA to remove the incorporated Cu2+, the polymeric film can repeatedly detect Cu2+ with good reversibility and film stability, as supported by XPS and TEM analyses. [Copyright &y& Elsevier]

The synthesis of π-conjugated organic materials through C–H activation and functionalization has recently received increasing attention. In this work, four pyrid-2-yl-appended para -phenylene oligomers (1 – 4) with two to five phenyl repeating units were synthesized via the Ru-catalyzed C–H activation of 2-phenylpyridine, followed by oxidative homocoupling or the arylation with a para -phenylene dibromide substrate. The single-crystal X-ray data and crystal packing of 1 and 3 are presented. In response to acid stimuli, the blue emissions of 1 – 3 are replaced by red-shifted cyan emissions, which are associated with the charge transfer transition from the phenylene backbone to the protonated pyridinium units. However, the emission of the longest congener 4 is largely quenched upon protonation. This length-dependent emission property is rationalized by DFT and TDDFT calculations. Image 1 [ABSTRACT FROM AUTHOR]