Jesse Lawrence Peltier

The substantial underrepresentation of American Indian, Alaskan Native, and Native Hawaiʻian (AI/AN/NH) students in Science, Technology, Engineering and Mathematics (STEM) majors at United States colleges and universities results from systemic barriers in higher education. Efforts to address inequities have thus far not led to increases in AI/AN/NH student participation in STEM at the national level. In fact, while the AI/AN/NH population in the United States is increasing, there was a 17.0% decrease in the number of bachelor's degrees awarded to Indigenous students in STEM during the period 2012–2021. This work reports on steps that can be taken in a variety of types of institutions of higher education to serve our Native students in STEM more effectively. These steps are reported as a series of rationales, followed by practical descriptions of implementations. Ideas for enhancing the Indigenous experience in the academy, together with examples of successful programs, are detailed. These include raising faculty and institutional cultural competency, addressing inequities in college preparation within the K‐12 system, making college STEM courses more inclusive, improving one‐on‐one advising and mentoring, engaging students in research, helping students overcome isolation, and providing physical spaces to build community. Implementation of these strategies will bring vast new talent to the STEM workforce, contributing to increased technical innovation and economic growth.

Cooperative gas adsorption in metal–organic frameworks (MOFs) is a rare phenomenon that generally involves long-range communication between multiple binding sites. We demonstrate a MOF containing cobalt(II)–methyl sites that selectively and reversibly capture two carbon monoxide (CO) molecules per site, leading to record-high adsorption capacities at ambient temperatures and pressures. Gas adsorption and structural, spectroscopic, and computational analyses support a mechanism in which binding of one CO molecule triggers a spin transition, followed by binding of a second CO molecule and migratory insertion of the first CO molecule into the cobalt–methyl bond to form an acetyl. The greater binding affinity associated with the second CO results in sigmoidal adsorption isotherms, a hallmark of cooperativity and phase-change materials, despite the absence of long-range interactions within the framework.

Carbenes, these neutral divalent carbon species have emerged as pivotal players in our laboratories. Despite their broad impact, direct characterization of these reactive molecules remains challenging in many cases. This concept article draws on recent literature to explore the strengths and limitations of the most widely used strategies for their identification.

N‐Heterocyclic carbene (NHC) ligands possess the ability to stabilize metal‐based nanomaterials for a broad range of applications. With respect to metal‐hydride nanomaterials, however, carbenes are rare, which is surprising if one considers the importance of metal‐hydride bonds across the chemical sciences. In this study, we introduce a bottom‐up approach that leverages preexisting metal‐metal m‐center‐n‐electron (mc‐ne) bonds to access a highly stable cyclic(alkyl)amino carbene (CAAC) copper‐hydride nanocluster, [(CAAC)₆Cu₁₄H₁₂][OTf]₂ with superior stability compared to Stryker's reagent, a popular commercial phosphine‐based copper hydride catalyst. Density functional theory (DFT) calculations reveal that the enhanced stability stems from hydride‐to‐ligand backbonding with the π‐accepting carbene. This new cluster emerges as an efficient and selective copper‐hydride pre‐catalyst, thereby providing a bench‐stable alternative for catalytic applications.

N‐Heterocyclic carbene (NHC) ligands possess the ability to stabilize metal‐based nanomaterials for a broad range of applications. With respect to metal‐hydride nanomaterials, however, carbenes are rare, which is surprising if one considers the importance of metal‐hydride bonds across the chemical sciences. In this study, we introduce a bottom‐up approach that leverages preexisting metal‐metal m‐center‐n‐electron (mc‐ne) bonds to access a highly stable cyclic(alkyl)amino carbene (CAAC) copper‐hydride nanocluster, [(CAAC)₆Cu₁₄H₁₂][OTf]₂ with superior stability compared to Stryker's reagent, a popular commercial phosphine‐based copper hydride catalyst. Density functional theory (DFT) calculations reveal that the enhanced stability stems from hydride‐to‐ligand backbonding with the π‐accepting carbene. This new cluster emerges as an efficient and selective copper‐hydride pre‐catalyst, thereby providing a bench‐stable alternative for catalytic applications.

N-Heterocyclic carbene (NHC) ligands possess the ability to stabilize metal-based nanomaterials for a broad range of applications. With respect to metal–hydride nanomaterials, however, carbenes are rare, which is surprising if one considers the importance of metal–hydride bonds across the chemical sciences. In this study, we introduce a bottom-up approach leveraging preexisting metal–metal m-center-n-electron (mc-ne) bonds to access a highly stable cyclic(alkyl)amino carbene (CAAC) copper–hydride nanocluster, [(CAAC)6Cu14H12][OTf]2. Using electrochemical measurements and thermogravimetric analysis we showcase that this cluster exhibits superior stability compared to Stryker’s reagent, a popular commercial phosphine-based copper hydride catalyst. Density Functional Theory (DFT) calculations reveal that the enhanced stability stems from hydride-to-ligand backbonding with the π-accepting carbene. This new cluster emerges as a highly efficient and selective copper–hydride pre-catalyst across six reaction classes, thereby providing a bench-stable alternative for catalytic applications.

A systematic study is presented on the physical and photophysical properties of isoelectronic and isostructural Cu, Ag, and Au complexes with a common amide (N-carbazolyl) and two different carbene ligands (i.e., CAAC = (5R,6S)-2-(2,6-diisopropylphenyl)6-isopropyl-3,3,9-trimethyl-2-azaspiro[4.5]decan-2-ylidene, MAC =1,3-bis(2,6-diisopropylphenyl)-5,5-dimethyl-4-keto-tetrahydropyri dylidene). The crystal structures of the (carbene)M^(I)(N-carbazolyl) (M^CAAC) and (MAC)M^(I)(N-carbazolyl) (M^MAC) complexes show coplanar carbene and carbzole ligands and C–M–N bond angles of ∼180°. The electrochemical properties and energies for charge transfer (CT) absorption and emission compounds are not significantly affected by the choice of metal ion. All six of the (carbene)M(Cz) complexes examined here display high photoluminescence quantum yields of 0.8–1.0. The compounds have short emission lifetimes (τ = 0.33−2.8 μs) that fall in the order Ag < Au < Cu, with the lifetimes of (carbene)Ag(Cz) roughly a factor of 10 shorter than for (carbene)Cu(Cz) complexes. Detailed temperature-dependent photophysical measurements (5–325 K) were carried out to determine the singlet and triplet emission lifetimes (τ_fl and τ_ph, respectively) and the energy difference between the singlet and triplet excited state, ΔE _S1−T1. The τ_fl values range between 20 and 85 ns, and the τ_ph values are in the 50–200 μs regime. The emission at room temperature is due exclusively to E-type delayed fluorescence or TADF https://www.w3.org/1998/Math/MathML"> ( i . e . , T 1 → Δ S 1 → S 0 + h ν ) . https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003088721/401d361c-71e4-4f2d-aaf9-31170aeac2be/content/math52-1_B.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/> . The emission rate at room temperature is fully governed bywith the silver complexes giving ΔE _S1−T1 values of 150–180 cmE _S1−T1 ⁻ ₁, (18–23 meV), whereas the gold and copper complexes give values of 570–590 cm⁻¹ (70–73 meV).

Amides are redox stereoelectronic chameleons, which can act as strong acceptors and allow for the design of air-stable radicals.

Many organic and main-group compounds, usually acids or bases, can accelerate chemical reactions when used in substoichiometric quantities, a process known as organocatalysis. In marked contrast, very few of these compounds are able to activate carbon monoxide, and until now, none of them could catalyze its chemical transformation, a classical task for transition metals. Herein we report that a stable singlet ambiphilic carbene activates CO and catalytically promotes the carbonylation of an o-quinone into a cyclic carbonate. These findings pave the way for the discovery of metal-free catalyzed carbonylation reactions.