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The amalgamation of different disciplines is at the heart of reticular chemistry and has broadened the boundaries of chemistry by opening up an infinite space of chemical composition, structure, and material properties. Reticular design has enabled the precise prediction of crystalline framework structures, tunability of chemical composition, incorporation of various functionalities onto the framework backbone, and as a consequence, fine-tuning of metal-organic framework (MOF) and covalent organic framework (COF) properties beyond that of any other material class. Leveraging the unique properties of reticular materials has resulted in significant advances from both a fundamental and an applied perspective. Here, we wish to review the milestones in MOF and COF research and give a critical view on progress in their real-world applications. Finally, we briefly discuss the major challenges in the field that need to be addressed to pave the way for industrial applications.

Chemical mediators are key compounds for controlling symbiotic interactions in the environment. Here, we disclose a fully stereoselective total synthesis of the algae differentiation factor (-)-thallusin that utilizes sophisticated 6-endo-cyclization chemistry and effective late-stage sp

Donor–acceptor Stenhouse adducts (DASAs) are visible‐light‐responsive photoswitches with a variety of emerging applications in photoresponsive materials. Their two‐step modular synthesis, centered on the nucleophilic ring opening of an activated furan, makes DASAs readily accessible. However, the use of less reactive donors or acceptors renders the process slow and low yielding, which has limited their development. We demonstrate here that 1,1,1,3,3,3‐hexafluoro‐2‐propanol (HFIP) promotes the ring‐opening reaction and stabilizes the open isomer, allowing greatly reduced reaction times and increased yields for known derivatives. In addition, it provides access to previously unattainable DASA‐based photoswitches and DASA–polymer conjugates. The role of HFIP and the photochromic properties of a set of new DASAs is probed using a combination of 1H NMR and UV/Vis spectroscopy. The use of sterically hindered, electron‐poor amines enabled the dark equilibrium to be decoupled from closed‐isomer half‐lives for the first time., The use of 1,1,1,3,3,3‐hexafluoro‐2‐propanol (HFIP) leads to a streamlined synthetic access to donor–acceptor Stenhouse adduct (DASA) photoswitches through shortened reaction times and increased yields. This approach enables the diversification of DASA structures through the use of previously unreactive donor or acceptor groups, as well as simple access to DASA–polymer conjugates even when using electron‐poor amine donors.

The monogermanide LuGe is obtained via high‐pressure high‐temperature synthesis (5–15 GPa, 1023–1423 K). The crystal structure is solved from single‐crystal X‐ray diffraction data (structure type FeB, space group Pnma, a=7.660(2) Å, b=3.875(1) Å, and c=5.715(2) Å, RF=0.036 for 206 symmetry independent reflections). The analysis of chemical bonding applying quantum‐chemical techniques in position space was performed. It revealed—beside the expected 2c‐Ge‐Ge bonds in the germanium polyanion—rather unexpected four‐atomic bonds between lutetium atoms indicating the formation of a polycation by the excess electrons in the system Lu3+(2b)Ge2−×1 e−. Despite the reduced VEC of 3.5, lutetium monogermanide is following the extended 8‐N rule with the trend to form lutetium‐lutetium bonds utilizing the electrons left after satisfying the bonding needs in the anionic Ge‐Ge zigzag chain., The germanium monogermanide is prepared by high‐pressure, high‐temperature synthesis. Chemical bonding in LuGe is described as covalently bonded zigzag chains of Ge atoms with the counterpart Lu4 polycations formed using excess electrons in sense of the Zintl count Lu3+(2b)Ge2−×1 e−. The homonuclear bonding in polycation in Lu4Ge4, which makes use of the electrons not required in the polyanion, resembles the situation in Ga2Se2.

The synthesis of complementary strands is the reaction underlying the replication of genetic information. It is likely that the earliest self-replicating systems used RNA as genetic material. How RNA was copied in the absence of enzymes and what sequences were most likely to have supported replication is not clear. Here we show that mixtures of dinucleotides with C and G as bases copy an RNA sequence of up to 12 nucleotides in dilute aqueous solution. Successful enzyme-free copying occurred with in situ activation at 4 °C and pH 6.0. Dimers were incorporated in favor of monomers when both competed as reactants, and little misincorporation was detectable in mass spectra. Simulations using experimental rate constants confirmed that mixed C/G sequences are good candidates for successful replication with dimers. Because dimers are intermediates in the synthesis of longer strands, our results support evolutionary scenarios encompassing formation and copying of RNA strands in enzyme-free fashion.

The N‐heterocyclic silylene [{Fe(η5‐C5H4‐NDipp)2}Si] (1DippSi, Dipp=2,6‐diisopropylphenyl) shows an excellent combination of pronounced thermal stability and high reactivity towards small molecules. It reacts readily with CO2 and N2O, respectively affording (1DippSiO2)2C and (1DippSiO)2 as follow‐up products of the silanone 1DippSiO. Its reactions with H2O, NH3, and FcPH2 (Fc=ferrocenyl) furnish the respective oxidative addition products 1DippSi(H)X (X=OH, NH2, PHFc). Its reaction with H3BNH3 unexpectedly results in B−H, instead of N−H, bond activation, affording 1DippSi(H)(BH2NH3). DFT results suggest that dramatically different mechanisms are operative for these H−X insertions., A stable cyclic diaminosilylene featuring a ferrocene‐based backbone is reported. The dicoordinate SiII atom is part of a six‐membered FeC2N2Si ring and shows a comparatively large bond angle of ca. 107°. This N‐heterocyclic silylene can activate strong bonds (C=O, N=O, B−H, N−H, P−H, O−H) under ambient conditions.

A structure-activity relationship study was performed for a set of rigidified platinum-acridine anticancer agents containing linkers derived from chiral pyrrolidine and piperidine scaffolds. Screening a library of microscale reactions and selected resynthesized compounds in non-small-cell lung cancer (NSCLC) cells showed that cytotoxicities varied by more than three orders of magnitude. A potent hit compound was discovered containing a (R)-N-(piperidin-3-yl) linker (P2-6R), which killed NCI-H460 and A549 lung cancer cells 100 times more effectively than the S enantiomer (P2-6S). P2-6R accumulated in A549 cells significantly faster and produced 50-fold higher DNA adduct levels than P2-6S. Ligand similarity analysis suggests that only module 6R may be compatible with strainless monofunctional intercalative binding. NCI-60 screening and COMPARE analysis highlights the spectrum of activity and potential utility of P2-6R for treating NSCLC and other solid tumors.

Reaction of CsF with ClF3 leads to Cs[Cl3 F10 ]. It contains a molecular, propeller-shaped [Cl3 F10 ]- anion with a central μ3 -F atom and three T-shaped ClF3 molecules coordinated to it. This anion represents the first example of a heteropolyhalide anion of higher ClF3 content than [ClF4 ]- and is the first Cl-containing interhalogen species with a μ-bridging F atom. The chemical bonds to the central μ3 -F atom are highly ionic and quite weak as the bond lengths within the coordinating XF3 units (X = Cl, and also calculated for Br, I) are almost unchanged in comparison to free XF3 molecules. Cs[Cl3 F10 ] crystallizes in a very rarely observed A[5] B[5] structure type, where cations and anions are each pseudohexagonally close packed, and reside, each with coordination number five, in the trigonal bipyramidal voids of the other.

The production of hydrogen via water electrolysis is feasible only if effective and stable catalysts for the oxygen evolution reaction (OER) are available. Intermetallic compounds with the well-defined crystal and electronic structures as well as particular chemical bonding features are suggested here to act as precursors for new composite materials with attractive catalytic properties. Al2Pt combines a characteristic inorganic crystal structure (anti-fluorite type) and a strongly polar chemical bonding with the advantage of elemental platinum in terms of stability against dissolution under OER conditions. We describe here the unforeseen performance of a surface nanocomposite architecture resulting from the self-organized transformation of the bulk intermetallic precursor Al2Pt in OER.

Fragment-based lead discovery has become a fundamental approach to identify ligands that efficiently interact with disease-relevant targets. Among the numerous screening techniques, fluorine-detected NMR has gained popularity owing to its high sensitivity, robustness, and ease of use. To effectively explore chemical space, a universal NMR experiment, a rationally designed fragment library, and a sample composition optimized for a maximal number of compounds and minimal measurement time are required. Here, we introduce a comprehensive method that enabled the efficient assembly of a high-quality and diverse library containing nearly 4000 fragments and screening for target-specific binders within days. At the core of the approach is a novel broadband relaxation-edited NMR experiment that covers the entire chemical shift range of drug-like 19 F motifs in a single measurement. Our approach facilitates the identification of diverse binders and the fast ligandability assessment of new targets.

An efficient application of a material is only possible if we know its physical and chemical properties, which is frequently obstructed by the presence of micro‐ or macroscopic inclusions of secondary phases. While sometimes a sophisticated synthesis route can address this issue, often obtaining pure material is not possible. One example is TaGeIr, which has highly sample‐dependent properties resulting from the presence of several impurity phases, which influence electronic transport in the material. The effect of these minority phases was avoided by manufacturing, with the help of focused‐ion‐beam, a μm‐scale device containing only one phase—TaGeIr. This work provides evidence for intrinsic semiconducting behavior of TaGeIr and serves as an example of selective single‐domain device manufacturing. This approach gives a unique access to the properties of compounds that cannot be synthesized in single‐phase form, sparing costly and time‐consuming synthesis efforts., Perfection not required: In a study of intrinsic properties of intermetallic compounds, the synthesis of either single‐crystal or single‐phase material is the fundamental step. However, some materials cannot be prepared in single‐phase form. A new approach using a micro‐scale amount of material to study its intrinsic properties can significantly shorten this procedure and make the quest for “perfect” samples unnecessary.

The competition between honeycomb and hexagonal tiling of molecular units can lead to large honeycomb superstructures on surfaces. Such superstructures exhibit pores that may be used as 2D templates for functional guest molecules. Honeycomb superstructures of molecules that comprise a C3 symmetric platform on Au(111) and Ag(111) surfaces are presented. The superstructures cover nearly mesoscopic areas with unit cells containing up to 3000 molecules, more than an order of magnitude larger than previously reported. The unit cell size may be controlled by the coverage. A fairly general model was developed to describe the energetics of honeycomb superstructures built from C 3 symmetric units. Based on three parameters that characterize two competing bonding arrangements, the model is consistent with the present experimental data and also reproduces various published results. The model identifies the relevant driving force, mostly related to geometric aspects, of the pattern formation., Molecular honeycomb superstructures were investigated using scanning tunneling microscopy, covering nearly mesoscopic areas and with unit cells containing up to 3000 molecules. A fairly general model was developed that describes the energetics of such structures and show that their sizes can be controlled by coverage.

Supramolecular polymerization of a donor-acceptor bisterpyridine (BTP) equipped with an electron-rich carbazole unit is observed by scanning tunneling microscopy (STM) at the highly oriented pyrolytic graphite (HOPG)|solution interface. It is shown that two-dimensional crystals of supramolecular (co)polymers are formed by chain growth polymerization, which in turn can be described by copolymerization statistics. From concentration-dependent measurements, derived copolymerization parameters and DFT calculations, a mechanism for self-assembly is developed that suggests a kinetically driven polymerization process in combination with thermodynamically controlled crystallization.

Previously published crystal structure determinations of two modifications of iodine azide (IN3) are corrected. In the original determinations, the very weak X‐ray reflections with odd k Miller indices had been discarded, resulting in too small unit cells and models with misordered, partly occupied atomic positions. Using the original diffraction data, refinements with the correct unit cells yield structures of polymeric (−I−N3−)n chains that are interlocked to layers. A skilled look at the primary X‐ray data is always recommended to overcome the lack of crystallographic expertise of computers at automated structure determinations., In the previous crystal structure determinations of both modifications of iodine azide half of the X‐ray reflections were missed, resulting in incorrect unit cells, incorrect space groups, and unsatisfactory structural models. Using the old data, but including the missed weak reflections, sensible structures were determined. It pays off to take a skilled look at the primary X‐ray data and not to rely solely on computer generated models.

Polymerization of nucleic acids in biology utilizes 5'-nucleoside triphosphates (NTPs) as substrates. The prebiotic availability of NTPs has been unresolved and other derivatives of nucleoside-monophosphates (NMPs) have been studied. However, this latter approach necessitates a change in chemistries when transitioning to biology. Herein we show that diamidophosphate (DAP), in a one-pot amidophosphorylation-hydrolysis setting converts NMPs into the corresponding NTPs via 5'-nucleoside amidophosphates (NaPs). The resulting crude mixture of NTPs are accepted by proteinaceous- and ribozyme-polymerases as substrates for nucleic acid polymerization. This phosphorylation also operates at the level of oligonucleotides enabling ribozyme-mediated ligation. This one-pot protocol for simultaneous generation of NaPs and NTPs suggests that the transition from prebiotic-phosphorylation and oligomerization to an enzymatic processive-polymerization can be more continuous than previously anticipated.