10.1039/b807895e
The research focuses on the development of a new ortho-metalation method for free ferrocenyl alcohols, enabling the synthesis of planar chiral ferrocene derivatives with high yields and diastereoselectivities. The experiments involved the preparation of racemic ferrocenyl-ethanol through Friedel–Crafts acylation of ferrocene, followed by LiAlH4 reduction, and subsequent kinetic enzymatic resolution using Novozyme 435s to obtain enantiopure alcohol (S)-1. Various lithiation conditions were tested, with n-BuLi in Et2O at -20°C yielding the best results for the formation of 1,2-disubstituted ferrocenyl alcohol 3a with a 95:5 diastereomeric ratio and a 79% yield. The dilithiated intermediate (S,pR)-2 was then reacted with different electrophiles to synthesize a variety of planar chiral ferrocene derivatives, with yields generally good and diastereomeric ratios in the range of 95:5. Analyses used included HPLC, 1H-NMR spectroscopy, and NMR spectroscopy for determining diastereomeric ratios and yields.
10.1021/jacs.7b00147
The study presents a novel physical organic approach to designing persistent, cyclable, low-potential electrolytes for nonaqueous redox flow batteries (RFBs), which are crucial for grid-scale energy storage. The researchers address the challenge of developing electrolytes that can operate at low or high potentials with the necessary stability and cycling lifetimes. They report the identification of a new pyridinium-based anolyte that can undergo electrochemical charge-discharge cycling at a low potential of -1.21 V versus Fc/Fc+ with minimal capacity loss after 200 cycles. The study involves the use of physical organic tools to predict and target electrolytes with the desired properties, applying this approach to a test case of anolyte candidate 1+. Through a systematic workflow that includes synthesis, decomposition rate measurements, physical-organic parameter identification, mathematical modeling, and validation, the researchers demonstrate the development of anolytes with enhanced persistence and low redox potentials, showing the potential for improving the performance and lifespan of RFBs.
10.1021/ja034994f
The research describes the development of "light-driven chiral molecular scissors," a molecular machinery that can perform open-close motions in response to light stimuli. The molecular scissors are composed of three essential components: handles, pivot, and blades. The pivot is made of ferrocene, chosen for its parallel, freely rotating cyclopentadienyl rings, and the handles are operated by azobenzene, which expands and contracts upon irradiation with UV and visible light, respectively. The molecular scissors were synthesized through a series of reactions starting from 1-aryl4-phenylcyclopenta-1,3-diene, involving steps like coupling with 3-ethynylaniline, hydrogenation, and oxidative coupling, yielding a mixture of trans and cis isomers. The researchers used circular dichroism (CD) spectroscopy and 1H NMR spectroscopy to analyze the motion of the剪刀. Upon UV irradiation, the trans-1 isomer converted to cis-1, causing changes in absorption and CD spectra, which were reversible with visible light irradiation. These spectral changes confirmed the reversible angular motion of the ferrocene unit, inducing the open-close motion of the blades.
10.1039/c0jm03365k
The research focuses on the design and synthesis of novel carbazole-based host materials, BCC-36, BTCC-36, BCC-27, and BTCC-27, for efficient solution-processed blue phosphorescent organic light-emitting diodes (OLEDs). These compounds were synthesized through palladium-catalyzed aromatic C–N coupling reactions and characterized using 1H-NMR, 13C-NMR, mass spectrometry, and elemental analysis. The thermal properties were investigated using TGA and DSC, while electrochemical properties were studied via cyclic voltammetry with TBAPF6 as the supporting electrolyte and ferrocene as the internal standard. The photophysical properties were examined through absorption and photoluminescent spectra in CH2Cl2. The performance of these compounds as host materials in OLEDs was evaluated by fabricating devices with a configuration of ITO/PEDOT:PSS/Host:OXD-7(30 wt%):FIrpic(10 wt%)/TPBI/Cs2CO3/Al and measuring their current density–voltage–luminance characteristics and efficiency. The experiments demonstrated that these new host materials resulted in OLEDs with low turn-on voltages, high current efficiencies, and high external quantum efficiencies, attributed to their high triplet energy levels, appropriate HOMO energy levels, and excellent film-forming abilities.
10.1021/om700807x
The study focuses on the regioselective syntheses and electrochemical characterization of ferrocene-based nanoelectronics, specifically targeting unsymmetric conjugated molecular frameworks containing diferrocene structures with mono- or dithioacetate end-groups for potential chemisorption onto Au(111) substrates. The chemicals used include 2,5-diethynylpyridyl- and 2,5-diethynylpyridinium-linked diferrocene frameworks, as well as 2,5-dimethoxyphenylethynyl-substituted ferrocene, which serves as an electron-withdrawing substituent affecting the Fe(II)/Fe(III) redox couple's potential. The purpose of these chemicals is to create molecular frameworks that can be integrated into metal lead/molecule/metal lead (LML) heterojunctions for nanoscale electronic devices, with the aim of understanding and improving electron transport through these junctions. The study provides detailed synthetic methods and electrochemical data to support the design and potential application of these molecular frameworks in molecular electronics.