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Abstract The conventional synthetic approach to transition metal pincer complexes calls for the preparation of the tridentate pincer (pro)ligand first, with subsequent introduction of the transition metal center as the last step. This work demonstrates that the alternative synthetic logic, where the central main group element is introduced last, can be applicable to a number of PEP pincer complexes (E=B, Al, Si, P) derived from phosphinophenols and phosphinopyrroles. This approach obviates the need to isolate well‐behaved propincer precursors, and instead relies on the formation of phosphine‐metal adducts first, whose nature determines the stoichiometry of the needed main group reagent to complete the synthesis. 

Abstract We report the facile synthesis and 3D printing of a series of triblock copolymers consisting of soft and hard blocks and demonstrate that alkene pendant groups of the hard block can be covalently modified. The polymers are prepared using a salenCo(III)TFA/PPNTFA binary catalyst system and 1,2‐propanediol as a chain transfer agent, providing an efficient one‐pot, two‐step strategy to tailor polymer thermal and mechanical properties. Thixotropic inks suitable for direct ink write printing were formulated by dissolving the block copolymers in organic solvent and dispersing NaCl particles. After printing, porous structures were produced by removing solvent and NaCl with water to give printed structures with surfaces that could be modified via UV‐initiated thiol‐ene click reactions. Alternatively, a tetra‐thiol could be incorporated into the ink and used for cross‐linking to give objects with high solvent resistance and selective degradability. 

Abstract To augment the fluoride binding ability of Lewis acidic stiboranes, we have synthesized and characterized a Sb^Vderivative (PhSbF₂((o‐(NH(2,6‐C₆H₃F₂)C₆H₄)₂,3) featuring diarylamine groups installed in proximity to the antimony center and poised to engage Sb‐bound fluoride anions in hydrogen bonding interactions. A competition experiment between3and Ph₃SbF₂(4) along with calculations show that the fluoride ion affinity of3is superior to that of4. 

An understanding of science concepts is important for living in modern society. Supporting adults’ science learning can be particularly challenging because most adults no longer attend formal educational institutions where access and opportunities are facilitated by teachers and school-sponsored programs. Biological field stations (BFSs) are a newly recognized educational venue that hold considerable intrinsic value for adult science education. In this study, we conducted a survey of 223 U.S. BFSs about their nonformal and informal educational outreach programs for adults. Results show BFSs offer a wide variety of science learning programs for adults, focused heavily on experiential learning to engage learners. These experiences promote interactions with the natural environment and are perceived to increase participants’ knowledge and skills. This study has implications for how adult educators can better support the professional development of science educators at BFSs and enrich the general public's science learning. 

Abstract Nuclear spin optical rotation (NSOR) has been investigated as a magneto‐optical effect, which holds the potential for applications, including hybrid optical‐nuclear magnetic resonance (NMR) spectroscopy and gradientless imaging. The intrinsic nature of NSOR renders its detection relatively insensitive, which has prevented it moving from a proof of concept to a method supporting chemical characterizations. In this work, the dissolution dynamic nuclear polarization technique is introduced to provide nuclear spin polarization, increasing the signal‐to‐noise ratio by several thousand times. NSOR signals of¹H and¹⁹F nuclei are observed in a single scan for diluted compounds, which has made this effect suitable for the determination of electronic transitions from a specific nucleus in a large molecule. 

Abstract C−H amination and amidation by catalytic nitrene transfer are well‐established and typically proceed via electrophilic attack of nitrenoid intermediates. In contrast, the insertion of (formal) terminal nitride ligands into C−H bonds is much less developed and catalytic nitrogen atom transfer remains unknown. We here report the synthesis of a formal terminal nitride complex of palladium. Photocrystallographic, magnetic, and computational characterization support the assignment as an authentic metallonitrene (Pd−N) with a diradical nitrogen ligand that is singly bonded to Pd^II. Despite the subvalent nitrene character, selective C−H insertion with aldehydes follows nucleophilic selectivity. Transamidation of the benzamide product is enabled by reaction with N₃SiMe₃. Based on these results, a photocatalytic protocol for aldehyde C−H trimethylsilylamidation was developed that exhibits inverted, nucleophilic selectivity as compared to typical nitrene transfer catalysis. This first example of catalytic C−H nitrogen atom transfer offers facile access to primary amides after deprotection.