Search

Sulfur‐coordinated coordination polymers (S−CPs) have unique optoelectrical properties that originate from infinite M−S bond networks. In this study, we synthesized and characterized two polymorphs of a two–dimensional (2D) Pb(II) S−CP with a formula of [Pb(tzdt)(OAc)] (Htzdt=1,3‐thiazolidine‐2‐thione, OAc=acetate). Our findings revealed that the thermodynamic product (KGF‐26) possesses quasi‐2D (−Pb−S−)n layers with weak nonbonded Pb−S bonds, whereas the kinetic product (KGF‐27) has intrinsic 2D (−Pb−S−)n layers with Pb−S bonds. The results of time‐resolved microwave conductivity measurements and first–principles calculations confirmed that KGF‐27 exhibits higher photoconductivity than KGF‐26, which establishes that the inorganic (−Pb−S−)n networks with Pb−S bonds are crucial for achieving high photoconductivity. This is the first experimental demonstration of the impact of the (−M−S−)n networks in S−CPs on photoconductivity through the comparison of crystal polymorphisms. [ABSTRACT FROM AUTHOR]

This study presents a new dehydrogenative synthesis of alkenyl isothiocyanates, providing compounds with bromo and isothiocyanate groups. These reactive functionalities offer versatility for further transformations. Application in an amine sensor utilizing a coumarin-attached product demonstrates practical utility. This streamlined approach facilitates access to alkenyl isothiocyanates, valuable tools for biological studies. [ABSTRACT FROM AUTHOR]

Coordination polymers containing a sulfur coordination atom (S-CPs) are an emerging class of materials with unique optoelectronic properties resulting from their inorganic metal–sulfur (–M–S–)n networks. Although the structural dimensionalities of (–M–S–)n networks govern the semiconductive properties of S-CPs, few systematic investigations have examined the impact of these dimensionalities on their semiconductive nature. In this study, we explored the relationship between the (–Pb–S–)n dimensionality and photoconductivity. We systematically synthesized Pb(II) S-CPs with the formula [Pb(x-SPhOMe)2] (x = ortho (KGF-32), meta (KGF-33), and para (KGF-34); HSPhOMe = methoxybenzenthiol). Single-crystal X-ray diffraction showed that KGF-32 and KGF-34 featured holodirected coordination spheres, but 1D (–Pb–S–)n chains with [PbO2S4] octahedra and 2D (–Pb–S–)n layers with [PbS6] octahedra, respectively. In contrast, KGF-33 features a 1D (–Pb–S–)n chain comprising a hemidirected [PbS5] coordination sphere. Notably, time-resolved microwave conductivity measurements and first-principles calculations revealed that the 2D-extended (–Pb–S–)n layer with the holodirected [PbS6] octahedron observed in KGF-34 served as a pathway for electron mobility. The findings of this study provide further design strategies for fabricating highly photoconductive Pb(II) S-CPs. [ABSTRACT FROM AUTHOR]

The Pb–S‐based coordination polymer (CP), named KGF‐9, [Pb(tadt)]n (tadt = 1,3,4‐thiadiazole‐2,5‐dithiolate), can selectively convert CO2 into HCOO− (>99%) under visible light, with an apparent quantum yield (AQY) of 2.6% at 400 nm, without a cocatalyst. However, KGF‐9 is an intrinsically nonporous CP, and its small specific surface area (<1 m2 g−1) might hinder the realization of its full potential as a photocatalyst. Herein, facile synthetic routes at room temperature are reported through a solid‐state reaction and a liquid‐phase reaction (LPR) using lead(II) acetate as a precursor. The use of lead(II) acetate promotes the deprotonation of the H2tadt ligand, resulting in a faster coordination reaction, a reduced feature size, and a drastic increase in specific surface area (≈10 m2 g−1). A higher AQY for formate production (5.9% at 400 nm) is found for KGF‐9 prepared via a 60 min LPR. The improved photocatalytic activity of the LPR sample is attributed to the presence of long‐lived charge carriers, which is revealed by time‐resolved microwave conductivity measurements. The results of this study provide a simple but effective strategy toward increasing the activity of CP‐based photocatalysts. [ABSTRACT FROM AUTHOR]

Hexaazatriphenylene (HAT) derivatives have attracted wide attention because of their electron‐deficient nature and unique self‐assembly properties. In this work, a facile synthesis method for obtaining HAT derivatives with alternating electron‐withdrawing nitrile and electron‐donating alkoxy groups (HATCNOCn) is proposed. Crystal structure analysis indicated that HATCNOCn forms a one‐dimensional columnar structure via strong π–π interactions. Density functional theory calculations revealed that the edge of HATCNOCn is divided into positively and negatively charged sites owing to the presence of alternating nitrile and alkoxy groups, which would induce strong π–π interactions. Thermal analysis and polarizing optical microscopy revealed that HATCNOCn exhibits columnar liquid‐crystal phases. Time‐resolved microwave conductivity measurements further demonstrated the photoconductive nature of HATCNOCn. The proposed strategy could provide a new strategy for the design of novel organic semiconductive materials. [ABSTRACT FROM AUTHOR]

Magnetoelectric (ME) materials exhibiting coupled electric and magnetic properties are of significant interest because of their potential use in memory storage devices, new sensors, or low‐consumption devices. Herein, we report a new category of ME material that shows liquid crystal (LC), ferroelectric (FE), and field‐induced single molecule magnet (SMM) behaviors. Co(II) complex incorporating alkyl chains of type [Co(3C16‐bzimpy)2](BF4)2 (1; 3C16‐bzimpy=2,2'‐(4‐hexadecyloxy‐2,6‐diyl)bis(1‐hexadecyl‐1H‐benzo[d]imidazole)) displayed a chiral smectic C mesophase in the temperature range 321 K–458 K, in which distinct FE behavior was observed, with a remnant polarization (88.3 nC cm−2). Complex 1 also exhibited field‐induced slow magnetic relaxation behavior that reflects the large magnetic anisotropy of the Co(II) center. Furthermore, the dielectric property of 1 was able to be tuned by an external magnetic field occurring from both spin‐lattice coupling and molecular orientational variation. Clearly, this multifunctional compound, combining LC, FE, and SMM properties, represents an entry to the development of a range of next‐generation ME materials. [ABSTRACT FROM AUTHOR]

The article titled "Polymorphism of Two-Dimensional Semiconducting Coordination Polymers: Impact of a Lead-Sulfur Network on Photoconductivity" explores the different structures and properties of a 2D PbII coordination polymer with Pb-S bonds. The cover picture showcases two polymorphs of the polymer, with one being the thermodynamic product and the other being the kinetic product. The thermodynamic product consists of quasi-2D layers with weak, nonbonded Pb-S bonds, while the kinetic product contains intrinsic 2D layers with Pb-S bonds. The kinetic product exhibits higher photoconductivity due to the presence of the intrinsic 2D layers. The research article by D. Tanaka and co-workers provides more detailed information on this topic. [Extracted from the article]

The article titled "Functionalized Polyamine Synthesis with Photoredox Catalysis" discusses the challenges in accessing modified polyamines and their potential for discovering bioactive compounds. The cover image illustrates the use of catalysts irradiated by light to facilitate the rapid functionalization of target polyamines, allowing for the attachment of various substituents. This process can lead to the development of novel bioactive molecules and molecular probes for chemical biology studies. The research article by K. Murakami and co-workers provides more detailed information on this topic. [Extracted from the article]

A dinuclear helical iron(ii) complex of a new ditopic thiazolylimine ligand (L) has been synthesised via supramolecular assembly. The resulting dinuclear helical cylinder [Fe2L3]·4BF4 was investigated by variable temperature X-ray crystallography, ESI high resolution mass spectrometry, CHN analysis, FT-IR and UV-Vis spectroscopy. The nature of the spin transition was investigated by magnetic susceptibility measurements, and confirmed by VT-SCXRD and X-ray photoelectron spectroscopy. [Fe2L3]·4BF4 displays a complete spin transition with a gradual-abrupt character at T1/2 = 348 K and represents a new example of a dinuclear iron(ii) complex exhibiting a spin transition at high temperature. Both VT-SCXRD and XPS measurements show excellent correlation with the magnetic susceptibility experiments, demonstrating the power of XPS not just to confirm, but also to clearly follow the spin-state transition in Fe(ii) SCO complexes. [ABSTRACT FROM AUTHOR]

The coordination metal complexes can exhibit flexibility in their electronic/magnetic state based on the combination of metal ions and the design of organic coordination ligands. Keywords: coordination complexes; dielectric properties; electronic polarization; ferroelectric materials; magnetic properties EN coordination complexes dielectric properties electronic polarization ferroelectric materials magnetic properties 1 1 1 06/28/23 20230601 NES 230601 B The cover feature image illustrates b the conceptual design of synergetic or coexistence of magnetic and dielectric functionalities in the coordination metal complexes. [Extracted from the article]