C—H bond oxidation reactions underscore the existing paradigm wherein high reactivity and high selectivity are inversely correlated. The development of catalysts capable of oxidizing strong aliphatic C(sp3)—H bonds while displaying chemoselectivity (i.e. tolerance of more oxidizable functionality) remains an unsolved problem. Herein, we describe a catalyst, manganese tert-butylphthalocyanine [Mn(tBuPc)], that is an outlier to the reactivity-selectivity paradigm. It is unique in its capacity to functionalize all types of C(sp3)—H bonds intramolecularly, while displaying excellent chemoselectivity in the presence of π-functionality. Mechanistic studies indicate that [Mn(tBuPc)] transfers bound nitrenes to C(sp3)—H bonds via a pathway that lies between concerted C—H insertion, observed with reactive noble metals (e.g. rhodium), and stepwise radical C—H abstraction/rebound, observed with chemoselective base metals (e.g. iron). Rather than achieving a blending of effects, [Mn(tBuPc)] aminates even 1° aliphatic and propargylic C—H bonds, reactivity and selectivity unusual for previously known catalysts.

SignificanceExploiting advanced 3D designs in micro/nanomanufacturing inspires potential applications in various fields including biomedical engineering, metamaterials, electronics, electromechanical components, and many others. The results presented here provide enabling concepts in an area of broad, current interest to the materials community––strategies for forming sophisticated 3D micro/nanostructures and means for using them in guiding the growth of synthetic materials and biological systems. These ideas offer qualitatively differentiated capabilities compared with those available from more traditional methodologies in 3D printing, multiphoton lithography, and stress-induced bending––the result enables access to both active and passive 3D mesostructures in state-of-the-art materials, as freestanding systems or integrated with nearly any type of supporting substrate.

capacity now achievable in the anode are not accessible. Consequently, substantial efforts are being expended to develop higher capacity cathode materials that might displace current commercial technologies with ones that are both robust in use and more environmentally benign over their service lifetime.Organic cathodes are a promising class of materials as they hold the possibility of replacing metal oxides with less environmentally impactful materials, while also improving performance metrics. [1,8] Many different organic cathode chemistries have been explored and are the subject of recent reviews. [9,10] Organic carbonyl compounds have emerged as the most promising class of organic cathode material due to their high energy density and electrochemical stability. [11] Small molecule carbonyl based cathodes such as pyrene-4,5,9,10-tetraone [12] and lithium rhodizoate [13] can provide capacities of up to 580 mA h g −1 , yet frequently suffer from dissolution in common electrolytes leading to capacity fade. Recent reports have successfully addressed dissolution of monomers by chemical interactions with either the binder [14] or current collector phase, [15] but these methods are not yet sufficiently developed to allow adoption in commercially relevant contexts.Polymerization is a more general technique for preventing active material dissolution. Recent advances made in the synthesis of polymeric quinone cathodes as well as an exhaustive list of studied materials can be found in literature reviews. [9][10][11]16] While the problem of quinone cathode dissolution has largely been solved by polymerization, polymer quinone cathodes have yet to achieve capacities similar to high performance monomers. The disconnect in performance between monomeric and polymeric quinones stems mainly from the incorporation of only two Li + per monomeric unit in the polymers reported to date. The only reports of a quinone polymer cathode incorporating more than two Li + per monomer is the four-electron redox of polymer bound pyrene-4,5,9,10-tetraone [17] and the four-electron redox of poly(anthraquinone norbornene). [18] In both examples of a four-electron redox quinone polymer, the large molecular framework of the monomer results in only modest capacities of the polymer (≈230 mA h g −1 for pyrene-4,5,9,10-tetraone [17] and 205 mA h g −1 for poly (anthraquinone norbornene)). [18] To our knowledge, the current record for highest capacity in a stable quinone polymer cathode is 275 mA h g −1 obtained using poly (benzoquinonyl sulfide) as the active material. [19] Despite recent advances, current polymeric organic cathode materials have failed to incorporate a high degree of lithium storage in a small molecular framework, resulting in low capacities relative to monomers. This report discloses the development of a lithium salt polymer of dihydroxyanthraquinone (LiDHAQS) capable of storing four Li + per monomer. The combination of storing four Li + per monomer and a low molecular weight monomer results in a capacity of 330 mA h g −1 , a record f...

The fundamental properties of the parent and substituted 2-pyridones (2-pyridone, 3-chloro-2-pyridone, and 3-formyl-2-pyridone) have been examined in the gas phase using computational and experimental mass spectrometry methods. Newly measured acidities and proton affinities are reported and used to ascertain tautomer preference. These particular substrates (as well as additional 3-substituted pyridones) were chosen in order to examine the correlation between leaving group ability and acidity for moieties that allow resonance delocalization versus those that do not, which is discussed herein.

In this work, the preparation and characterization of modified LiMn2O4 (LMO) cathodes utilizing chemisorbed alkylphosphonic acids to chemically modify their surfaces are reported. Electrochemical methods to study ionic and molecular mobility through the alkylphosphonate self‐assembled monolayers (SAMs) for different alkyl chain compositions, in order to better understand their impact on the lithium‐ion electrochemistry, are utilized. Electrochemical trends for different chains correlate to trends observed in contact angle measurements and solvation energies obtained from computational methods, indicating that attributes of the microscopic wettability of these interfaces with the battery electrolyte have an important impact on ionic mobility. The effects of surface modification on Mn dissolution are also reported. The alkylphosphonate layer provides an important mode of chemical stabilization to the LMO, suppressing Mn dissolution by 90% during extended immersion in electrolytes. A more modest reduction in dissolution is found upon galvanostatic cycling, in comparison to pristine LMO cathodes. Taken together, the data suggest that alkylphosphonates provide a versatile means for the surface modification of lithium‐ion battery cathode materials allowing the design of specific interfaces through modification of organic chain functionalities.