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Incorporating the SF₅ group into organic molecules is a powerful strategy for pushing the boundaries of chemistry and driving progress in drug discovery. In this context,a synthetic route to backbone-connected pentafluorosulfanyl β-amino esters is reported, which combine the unique physicochemical properties of the SF₅ group with those of β-amino acids. The approach begins with the preparation of an unprecedented library of (E)-α-SF₅-α,β-unsaturated esters via aldol condensation of SF₅ acetates with aldehydes. These SF₅-substituted Michael acceptors undergoes N-nucleophilic attack at the β-carbon under mild, practical conditions, affording a diverse array of α-SF₅-β^2,3-amino esters. The reactions deliver excellent yields and high diastereoselectivity, generating syn adducts with two contiguous stereogenic centers.

Silylium ions, three-coordinated as well as donor-stabilized, have attracted the interest of chemists for many years, have paved its way into practical application as catalysts for organic reactions, and have contributed to the understanding of fundamental chemistry problems. Since the first carbenes have been isolated and characterized, they had and still have an ongoing enormous impact on organic as well as on inorganic and organometallic chemistry. Herein, the synthesis and complete characterization of silatranyl cations as their acetonitrile- respectively propionitrile-coordinated hexachlorido antimonates is reported. Upon interaction of the former with 4-dimethylaminopyridine (DMAP) conversion to an unprecedented carbene–type complex of antimony pentachloride occurred, nicely combining silylium and carbene chemistry.

To harness the potential of rotary molecular systems (RMSs), it is basic to operate beyond thermodynamic equilibrium, requiring a continuous energy input. Light, due to its abundance, noninvasive nature, and precise spatial and temporal control, serves as an ideal energy source. This review highlights recent advances in bioinspired light-driven RMSs, with a particular focus on strategies to shift their activation wavelengths from UV to the visible and near-infrared regions through tailored structural modifications. A range of photochemical mechanisms underlying these systems, from reversible switching to unidirectional rotation, including emerging hybrid mechanisms that integrate multiple photophysical and/or chemical processes to achieve complex multistates behavior is discussed. Furthermore, it is explored that how specific molecular designs impact key photo-efficiency such as quantum yield and photostationary state distribution. These insights offer guiding principles to enhance the efficiency and functionality of RMSs and pave the way toward their integration in biomedical technologies requiring light-responsive control, such as targeted drug delivery and advanced imaging systems.

Amphirionin-5, derived from dinoflagellates of the genus Amphidinium, exhibits a unique biological activity whereby trace amounts can lead to potent proliferation of osteoblasts, making it a promising candidate for regenerative therapy of bone and treatment of osteoporosis. However, the relative configuration of amphirionin-5 has only been partially determined. Herein, the total synthesis of amphirionin-5 is undertaken to establish its overall stereochemistry. Synthesized C16-C28 model with the proposed relative configuration of C19-C23 shows significant discrepancies between its NMR spectroscopic data around C19 and those of the corresponding substructures of the natural amphirionin-5, suggesting of necessity for reconsideration of the relative configuration of C19. Two further 19S-type C11-C28 models are synthesized, and detailed NMR analysis reveals that the ¹³C NMR of (19S,26R)-C11-C28 models show the best agreement with those in the corresponding substructure of the natural product; thus, the relative configurations from C19 to C26 of amphirionin-5 are proposed as 19S*, 20S*, 23S*, and 26R*. Coupling of the C1-C16 segment, synthesized from an optically active α-silyloxy pentanolide as a common intermediate, and the (19S,26R)-C17-C28 segment is achieved under intermolecular Stetter reaction conditions, enabling the convergent total synthesis of the candidate diastereomer of amphirionin-5. Ultimately, the overall stereochemistry of amphirionin-5 is fully assigned.

Chalcogenide perovskites are an intriguing candidate for stable and nontoxic semiconductor devices, including multijunction photovoltaics. Experimental evidence that these materials can be made with high optoelectronic quality has often eluded researchers but has finally been shown in a recent publication by the Dimitrievska group. These findings motivate further efforts to develop of the first chalcogenide perovskite solar cells and better understand defect chemistry in these materials.

This manuscript introduces a novel approach for quantifying the strength of halogen and chalcogen bonding interactions involving heavy elements of groups 17 (Br, I) and 16 (Se, Te). While X-ray photoelectron spectroscopy (XPS) is a recognized diagnostic tool for halogen bonding, its application for characterizing chalcogen bonds, or quantifying the strength of either interaction via spectral shifts, remains unexplored. To current knowledge, this study is the first to propose and rigorously validate such an approach. A comprehensive benchmark investigation is first conducted to identify the most reliable theoretical methods for reproducing experimental XPS signals. Subsequently, a clear correlation between calculated XPS shifts and the interaction strength is established, demonstrating XPS as a novel and experimentally accessible method. This work aims to significantly advance the understanding and rational design of noncovalent interactions in supramolecular chemistry and materials science.

A protocol for the multigram scale synthesis of the bench stable salt S-(cis-2,3-bis(trifluoromethyl)cyclopropyl)dibenzothiophenium tetrafluoroborate 1 is reported. This compound is used as a versatile reagent for the mild transfer of the cis-2,3-bis(trifluoromethyl)cyclopropyl moiety (cis-BTFC) to structurally complex heterocycles under photochemical conditions. The radical process tolerates a number of functional groups and proceeds with retention of the original cis-configuration. The newly introduced cis-BTFC chemotype is characterized by a van der Waals volume of 115 ų, which sets its steric demand between those of the heptafluoroisopropyl (HFIP, 99 ų) and the perfluorotertbutyl units (PFTB, 128 ų). Notably, the experimentally determined lipophilicity value (Log P) indicates that the cis-BTFC scaffold imparts significant higher polarity to the carrying structure than both HFIP and PFTB, making this motif potentially attractive for the optimization of pharmacokinetic profiles during drug optimization campaigns. Interestingly, under basic treatment, typical N-, O-, or S-nucleophiles also react with 1, but mixtures of the cis- and trans-BTFC containing products are obtained in varying ratios. Mechanistic studies confirm the in situ generation of 1,3-bis(trifluoromethyl)cyclopropane, which subsequently reacts with nucleophiles in a Michael-type fashion.

Helix-sense-selective polymerization (HSSP) is a powerful method for the synthesis of preferred-handed helical macromolecules. This article presents a new method for controlling the HSSP of an achiral 4-alkoxy-3,5-bis(hydroxymethyl)phenylacetylene derivative, using an axially chiral heptaarylhexa-1,3,5-trienylrhodium(I) complex as an initiator. Hydrophobic components, such as a tert-butyl group and tetrafluorobenzobarrelene (tfb) ligand, are introduced into the rhodium complex to increase its solubility in eluents, including n-hexane, and sufficient amounts of enantioenriched samples are obtained by optical resolution using chiral high performance liquid chromatography. The complex is used as an initiator for the HSSP of an achiral 4-alkoxy-3,5-bis(hydroxymethyl)phenylacetylene derivative at a lower temperature. The HSSP proceeds in a controlled manner, yielding the corresponding poly(phenylacetylene) derivative with a molecular weight roughly consistent with the value expected from the feed ratio of the monomer to the initiator. Circular dichroism (CD) spectra of the resultant polymers indicate the formation of a one-handed helical structure in the polymer backbone. The CD intensity of the resultant polymers increases with increasing feed ratio up to ≈150 but gradually decreases beyond that point, indicating that the helical sense of the polymer determined in the initiation step by the chirality of the initiator can persist up to 150 repeating units.

In biology, the specific enzyme-mediated cleavage of peptide and protein backbones plays numerous regulatory roles. Being able to mimic the specificity and efficacy of enzymes, using chemical methods, is a grand challenge. Nevertheless, specific chemical cleavage of protein backbones at cysteine residues dates back to the 1960s. In this concept, recent insights and developments in chemical peptide and protein backbone cleavage as well as their applications for the selective manipulation and functionalization of proteins are discussed.

A ternary metal catalyst system based on Pd/C-Pt/C-Ru/C and molecular oxygen is found to be very effective and robust in oxidizing alcohols to carboxylic acids. Using the ternary catalyst and a flow-setup, the conversion of 5-hydroxymethylfurfural (HMF, 1) to 2,5-furandicarboxylic acid (FDCA, 2), a bioplastics precursor, proceeded quite rapidly with a residence time of 1 min at 120 °C under 0.28 MPa of molecular oxygen. Catalyst activity remains stable for at least 2 weeks, giving 66.8 g (60% yield) of the analytically pure FDCA (2). The ternary catalyst system combined with a flow setup is successfully applied to the rapid conversion of ordinary alcohols 3 to aromatic and aliphatic carboxylic acids 4 in good yields.