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Iron cyanide compounds are among the oldest known synthetic coordination compounds, dating back to the early 18thcentury. By contrast, iron complexes of the cyaphide ion (C≡P–)─a heavy valence isoelectronic analog of the cyanide ion─are unknown. Herein we report the synthesis of highly stable mono- and bis-cyaphide complexes of iron(II), namely Fe(depe)2(Cl)(CP) and Fe(depe)2(CP)2(depe = 1,2-bis(diethylphosphino)ethane). These iron(II) cyaphide complexes are capable of further coordination to iron(I) in a hitherto unknown linear coordination geometry, affording the conjugated multimetallic mixed-valence complexes [{Fe(depe)2}2(μ-CP)(N2)][BArF4]2and [{Fe(depe)2}3(μ-CP)2][OTf]2.

Despite their relevance to catalysis, low-/subvalent cobalt complexes are difficult to synthesize and isolate. Consequently, very few “cobaltate” complexes are known and there is a lack of architectural diversity in this field. Lewis acidic d0group IV metals have been demonstrated to stabilize Co–Icenters via metal–metal bonds. Herein, we report the synthesis of bis(phosphinoamide) heterobimetallic MIV/Co–Iarene complexes (M = Zr, Hf). The driving force to maintain the aromaticity of the arenes dictates the hapticity of the Co-bound arene ligands and influences the binding arrangement of the phosphinoamide ligands. Benzene and toluene were observed to bind η6to the Co–Icenter, forcing dissociation of one of the phosphinoamide ligands, whereas η4-coordination of anthracene allows both phosphinoamide ligands to remain bound to the Co center. The identity of both the arene and the group IV metal ion starkly influence the lability of the arene. For instance, the Co-bound benzene ligand in the ZrIV/Co–Ibenzene complex rapidly exchanges with C6D6in solution, whereas toluene/C6D6exchange is much slower and appreciable C6H6/C6D6exchange is not observed for the Hf analogue. The ZrIV/Co–Ibenzene complex loses benzene upon repeated exposure to vacuum to form an arene-free tetrametallic dimer.

The bonding interactions and electronic structure of a diphosphine pincer ligand featuring an N-heterocyclic phosphenium/phosphido (NHP±) central moiety with nickel are explored. Treating Ni(COD)2with the pincer ligand [PPP]Cl in the presence of a two-electron phosphine donor ligand PMe3generates chlorophosphine complex (PPClP)Ni(PMe3) (2a). The cationic Ni complex [(PPP)Ni(PMe3)][BPh4] (3a) can be prepared by subsequent halide abstraction from 2awith NaBPh4. The assignment of 3aas a Ni0/NHP+complex, based on analysis of structural parameters and computational investigations, lies in contrast to its previously reported group 10 MII/NHP–(M = Pd, Pt) analogues. The activation of O–H bonds across the Ni–PNHPbond is demonstrated by the addition of isopropanol to afford the metal hydride species [(PPOiPrP)Ni(PMe3)(H)][BPh4] (4). Notably, the installation of a P–H bond in the NHP unit by treatment of 2awith LiAlH4yields (PPHP)Ni(PMe3) (6). The ambiphilic nature of the P–H bond was demonstrated through reactivity studies of P–H bond cleavage in comparison to a Pd analogue (PPHP)Pd(PPh3) (8).

The delivery of prompt and appropriate antimicrobial therapy for life-threatening infections is an important antimicrobial stewardship measure and a priority for hospitals.

The activation of C–H bonds using first-row transition metals poses a formidable challenge in the development of sustainable catalytic methods. Early/late heterobimetallic complexes provide a Lewis acidic binding site for directing groups, facilitating the activation of C–H bonds at an appended first-row transition metal center. Herein, the reactivity of the ZrIV/Co–Iheterobimetallic complexes (THF)(I)Zr(XylNPiPr2)2Co(PR3) (1-PR3; Xyl = 3,5-dimethylphenyl; PR3= PMe3, PPh2Me) toward directed C–H bond activation is explored with pyridine and terminal alkyne derivatives. 1-PMe3reacts reversibly with 4-methylpyridine to afford the C–H activated complex (4-Me-C5H4N)(I)Zr(XylNPiPr2)2(μ-4-Me-C5H3N)Co(PMe3)(H) (3-PMe3). By using the more Lewis basic substrate 4-tert-butylpyridine, (I)Zr(XylNPiPr2)2(μ-4-tBu-C5H3N)Co(PMe3)(H) (4-PMe3) is formed irreversibly. In addition to pyridine derivatives, 1-PPh2Mecan activate the C–H bond of terminal alkynes to form (THF)(I)Zr(XylNPiPr2)2(μ-R′C≡C)Co(PPh2Me)(H) (R′ = Ph (5-PPh2Me); R′ = SiMe3(6-PPh2Me)).

A pair of bimetallic compounds featuring Fe–Fe bonds, [Fe(iPrNPPh2)3FeR] (R = PMe3, ≡NtBu), have been investigated using High-Frequency Electron Paramagnetic Resonance (HFEPR) as well as field- and temperature-dependent 57Fe nuclear γ resonance (Mössbauer) spectroscopy. To gain insight into the local site electronic structure, we have concurrently studied a compound containing a single Fe(II) in a geometry analogous to that of one of the dimer sites. Our spectroscopic studies have allowed for the assessment of the electronic structure via the determination of the zero-field splitting and 57Fe hyperfine parameters for the entire series. We also report on our efforts to correlate structure with physical properties in metal–metal bonded systems using ligand field theory guided by quantum chemical calculations. Through the insight gained in this study, we discuss strategies for the design of single-molecule magnets based on polymetallic compounds linked via direct metal–metal bonds.

A convenient nickel-templated phenyl elimination route is described for the synthesis of phosphide-containing multidentate ligands from triarylphosphine precursors. Treating Ni(COD)2with the neutral bis(amine)/bis(phosphine) ligand precursor H24Ph[PNNP]affords bis(amido)/bis(phosphine) complex 1. Treatment of 1with 1 equiv of KH leads to elimination of a phenyl group from one of the phosphine fragments, generating bis(amido)/phosphine/phosphido complex 3Ph[PNNP]Ni–(2). Alternatively, excess KH or nBuLi affords the bis(amido)/bis(phosphide) complex 2Ph[PNNP]Ni2–(3or 4, respectively) by elimination of two phenyl substituents. These reactions are high-yielding and provide a unique and straightforward route to chelating phosphido ligands that would otherwise be challenging to synthesize.

A tridentate [PPP] ligand has been used to construct a series of dimeric cobalt complexes and explore cooperative multielectron redox processes that are both metal- and ligand-centered. Reduction of (PPClP)CoCl2(1) with excess magnesium affords the CoICoIN-heterocyclic phosphido (NHP–)-bridged symmetric dimer [(μ-PPP)Co]2(2). Two-electron oxidation of 2with FcPF6generates an asymmetrically bridged dication [(μ-PPP)Co]2[PF6]2(3) in which the oxidation has occurred in a delocalized fashion throughout the Co2P2core. In contrast, [(μ-PPP)Co]2+(5), which can be generated either by one-electron oxidation of 2with FcPF6or comportionation of 2and 3, features an asymmetric geometry and localized mixed valence. Treatment of 1with the milder reductants CoCp2and KBEt3H does not lead to formation of 2, 3, or 5but instead generates dimeric species [(PPP)CoCl]2(6) and [(PPP)CoH]2(7). Unlike 2–5, where the phosphine side arms of the tridentate [PPP] ligand span the two Co centers, complex 6and 7are connected solely by NHP–ligands that bridge the two (PPP)Co fragments.

Bulletin boards can be used as an educational aid for older adults thereby encouraging patients to make healthy lifestyle choices. Some of the suggestions that an be incorporated to make bulletin board work include posting bulletin in heavily traveled areas or even in patients rooms, considering the entire population when planning any bulletin board, and providing translated version if some of the clients speak language other than language used.

The development of metalated covalent organic frameworks (COFs) is useful for generating recyclable catalytic systems for practical applications. Herein, we report the synthesis, characterization, and catalytic properties of an azine-linked two-dimensional (2D) COF containing nickel-doped dehydrobenzoannulene (DBA) units. We demonstrate that Ni-DBA-2D-COF can be used to reductively cleave the aryl C–S bonds of several organosulfur compounds utilizing dimethylethylsilane as the reducing agent. The Ni-DBA-2D-COF catalytic system displays excellent recyclability and good yields. This work highlights a rare example of utilizing metalated DBA complexes to perform catalytic transformations.

Oxygen reduction is a critical half reaction in renewable fuel cell development and a key step in the development of aerobic oxidation reactions. Herein, we report rapid two-electron O2reduction by a d0ZrIVcenter with an appended redox-active Co–Isite serving as an electron reservoir. The early/late heterobimetallic Zr/Co complex (THF)Zr(MesNPiPr2)3CoCNtBu (1) reacts readily with O2and O atom transfer reagents to generate reactive oxygenated species including terminal peroxo and oxo complexes, (O2)Zr(MesNPiPr2)3CoCNtBu (2) and O≡Zr(MesNPiPr2)3CoCNtBu (3). The bimetallic Zr/Co complex provides a new cooperative synthetic pathway to promote multielectron redox processes such as oxygen reduction, with each metal playing a distinct role as a substrate binding site or redox mediator.

Objectives: Mpox surveillance was integral during the 2022 outbreak response. We evaluated implementation of mpox surveillance in Tennessee during an outbreak response and made recommendations for surveillance during emerging infectious disease outbreaks.Methods: To understand surveillance implementation, system processes, and areas for improvement, we conducted 8 semistructured focus groups and 7 interviews with 36 health care, laboratory, and health department representatives during September 9-20, 2022. We categorized and analyzed session transcription and notes. We analyzed completeness and timeliness of surveillance data, including 349 orthopoxvirus-positive laboratory reports from commercial, public health, and health system laboratories during July 1–August 31, 2022.Results: Participants described an evolving system and noted that existing informatics platforms inefficiently supported iterations of reporting requirements. Clear communication, standardization of terminology, and shared, adaptable, and user-friendly informatics platforms were prioritized for future emerging infectious disease surveillance systems. Laboratory-reported epidemiologic information was often incomplete; only 55% (191 of 349) of reports included patient address and telephone number. The median time from symptom onset to specimen collection was 5 days (IQR, 3-6 d), from specimen collection to laboratory reporting was 3 days (IQR, 1-4 d), from laboratory reporting to patient interview was 1 day (IQR, 1-3 d), and from symptom onset to patient interview was 9 days (IQR, 7-12 d).Conclusions: Future emerging infectious disease responses would benefit from standardized surveillance approaches that facilitate rapid implementation. Closer collaboration among informatics, laboratory, and clinical partners across jurisdictions and agencies in determining system priorities and designing workflow processes could improve flexibility of the surveillance platform and completeness and timeliness of laboratory reporting. Improved timeliness will facilitate public health response and intervention, thereby mitigating morbidity.

A one-pot synthetic procedure for a series of bimetallic Nb/M complexes, Cl–Nb(iPrNPPh2)3M–X (M = Fe (2), Ni (4), Cu (5)), is described. A similar procedure aimed at synthesizing a Nb/Co analogue instead affords iPrN═Nb(iPrNPPh2)2(μ-PPh2)Co–I (3) through cleavage of one phosphinoamide P–N bond under reducing conditions. Complexes 4and 5are found to have short Nb-M distances, corresponding to unusual metal–metal bonds between Nb and these first row transition metals. For comparison, a series of heterobimetallic O≡Nb(iPrNPPh2)3M–X complexes (M = Fe (7), Co (8), Ni (9), Cu (10)) was synthesized. In these complexes, the NbVcenter is engaged in sufficient π-bonding to the terminal oxo ligand to remove the driving force for direct metal–metal interactions. A comparison of the cyclic voltammograms of 2and 4–10reveals that the presence of a second metal shifts the redox potentials of both Nb and the late metal center anodically, even when direct metal–metal interactions are not present.

Heterodinuclear transition metal complexes with a direct metal–metal interaction offer the potential of unique reactivity compared with mononuclear catalysts. Heterodinuclear Co–Zr complexes with phosphinoamide ligands bridging Co and Zr metal centers are effective precatalysts for Kumada C–C bond coupling reactions between alkyl halides and alkyl Grignards. In contrast, the analogous mononuclear Co tris(phosphinoamine) complex without Zr provides very inefficient catalysis. Here we describe density functional theory calculations that reveal the mechanistic and reactivity impact of the Co–Zr metal–metal interaction and phosphinoamide ligands on alkyl halide–alkyl Grignard Kumada coupling catalysis. The Co–Zr interaction enables two-electron reduction of the precatalyst to form an active catalyst, which then promotes a low-energy electron-transfer alkyl halide oxidative addition mechanism. The Co–Zr interaction and the phosphinoamide ligands bridging the metal centers provide a dialkyl intermediate with a low-energy C–C bond forming reductive elimination route through a phosphine dissociation pathway, which is not viable for an analogous mononuclear Co complex.

Direct metal–metal bonding of two distinct first-row transition metals remains relatively unexplored compared to their second- and third-row heterobimetallic counterparts. Herein, a recently reported Fe–V triply bonded species, [V(iPrNPPh2)3FeI] (1; Kuppuswamy, S.; Powers, T. M.; Krogman, J. P.; Bezpalko, M. W.; Foxman, B. M.; Thomas, C. M. Vanadium–iron complexes featuring metal–metal multiple bonds. Chem. Sci.2013, 4, 3557–3565), is investigated using high-frequency electron paramagnetic resonance, field- and temperature-dependent 57Fe nuclear gamma resonance (Mössbauer) spectroscopy, and high-field electron-electron double resonance detected nuclear magnetic resonance. From the use of this suite of physical methods, we have assessed the electronic structure of 1. These studies allow us to establish the effective g̃tensors as well as the Fe/V electro-nuclear hyperfine interaction tensors of the spin S= 1/2ground state. We have rationalized these tensors in the context of ligand field theory supported by quantum chemical calculations. This theoretical analysis suggests that the S= 1/2ground state originates from a single unpaired electron predominately localized on the Fe site.

Two cobalt complexes containing coordinated N-heterocyclic phosphenium (NHP+) ligands are synthesized using a bidentate NHP+/phosphine chelating ligand, [PP]+. Treatment of Na[Co(CO)4] with the chlorophosphine precursor [PP]Cl (1) affords [PP]Co(CO)2(2), which features a planar geometry at the NHP+phosphorus center and a short Co–P distance [1.9922(4) Å] indicative of a CoP double bond. The more electron-rich complex [PP]Co(PMe3)2(3), which is synthesized in a one-pot reduction procedure with 1, CoCl2, PMe3, and KC8, has an even shorter Co–P bond [1.9455(6) Å] owing to stronger metal-to-phosphorus back-donation. The redox properties of 2and 3were explored using cyclic voltammetry, and oxidation of 3was achieved to afford [[PP]Co(PMe3)2]+(4). The electron paramagnetic resonance spectrum of complex 4features hyperfine coupling to both 59Co and 31P, suggesting strong delocalization of the unpaired electron density in this complex. Density functional theory calculations are used to further explore the bonding and redox behavior of complexes 2–4, shedding light on the potential for redox noninnocent behavior of NHP+ligands.

To understand the metal–metal bonding and conformational flexibility of first-row transition metal heterobimetallic complexes, a series of heterobimetallic Ti/M and V/M complexes (M = Fe, Co, Ni, and Cu) have been investigated. The titanium tris(phosphinoamide) precursors ClTi(XylNPiPr2)3(1) and Ti(XylNPiPr2)3(2) have been used to synthesize Ti/Fe (3), Ti/Ni (4, 4THF), and Ti/Cu (5) heterobimetallic complexes. A series of V/M (M = Fe (7), Co (8), Ni (9), and Cu (10)) complexes have been generated starting from the vanadium tris(phosphinoamide) precursor V(XylNPiPr2)3(6). The new heterobimetallic complexes were characterized and studied by NMR spectroscopy, X-ray crystallography, electron paramagnetic resonance, and Mössbauer spectroscopy, where applicable, and computational methods (DFT). Compounds 3, 4THF, 7, and 8are C3-symmetric with three bridging phosphinoamide ligands, while compounds 9and 10adopt an asymmetric geometry with two bridging phosphinoamides and one phosphinoamide ligand bound η2to vanadium. Compounds 4and 5, on the other hand, are asymmetric in the solid state but show evidence for fluxional behavior in solution. A correlation is established between conformational flexibility and metal–metal bond order, which has important implications for the future reactivity of these and other heterobimetallic molecules.

The bonding interactions of a synthesized pincer-ligated manganese dicarbonyl complex featuring an N-heterocyclic phosphenium (NHP+) central moiety are explored. The pincer ligand [PPP]Cl was coordinated to a manganese center using Mn(CO)5Br and 254 nm light to afford the chlorophosphine complex (PPClP)Mn(CO)2Br (2) as a mixture of halide exchange products and stereoisomers. The target dicarbonyl species (PPP)Mn(CO)2(3) was prepared by treatment of 2with 2 equiv of the reductant KC8. Computational investigations and analysis of structural parameters were used to elucidate multiple bonding interactions between the Mn center and the PNHPatom in 3. The generation of a product of formal H2addition, (PPHP)Mn(CO)2H (4), was achieved through the dehydrogenation of NH3BH3, affording a 2:1 mixture of 4syn:4antistereoisomers. The nucleophilic nature of the Mn center and the electrophilic nature of the PNHPmoiety were demonstrated through hydride addition and protonation of 3to produce K(THF)2[(PPHP)Mn(CO)2] (6) and (PPClP)Mn(CO)2H (5), respectively. The observed reactivity suggests that 3is best described as a Mn–I/NHP+complex, in contrast to pincer-ligated dicarbonyl manganese analogues typically assigned as MnIspecies.

A single bridging phosphinoamide ligand was shown to support a metal–metal triple bond in a Zr/Co heterobimetallic complex. The similarity of the bonding in this compound to previously synthesized Zr/Co species, and therefore the assignment of the Zr/Co triple bond, is supported by the structural parameters of the complex, the electronic structure predicted by density functional theory, and complete-active-space self-consistent-field (CASSCF) calculations. This demonstrates that metal–metal multiple bonds can be realized in heterobimetallic complexes without multiple bridging ligands to enforce the proximity of the two metals.

Despite the utility of Si–Si bonds, there are relatively few examples of Si–Si bond formation by base metals. In this work, a four-coordinate iron complex, (PNNP)FeII, is shown to strongly activate the Si–H bonds in primary silanes across the Fe–amide bonds in a metal–ligand cooperative fashion. Upon treatment with excess silane, Si–Si dehydrogenative homocoupling is shown to occur across the Fe–Namidebond without concomitant oxidation and spin state changes at the Fe center.

A Co(II) complex, (PPHP)CoI2, was synthesized and evaluated as a precatalyst for the hydrogenation of terminal alkenes under mild conditions (1 atm H2, ambient temperature) using KBEt3H as an activator. This catalytic system was found to be active for terminal alkene substrates, including 1,1′-disubstituted alkenes, and to exhibit modest air and moisture stability. A preliminary investigation into substrate scope and functional group tolerance was performed. Upon the completion of catalytic reactions, the sole metal complex observed was identified as the dimeric species [(PPP)CoH]2suggesting that the catalytically active species may be a cobalt hydride monomer.

Simulation experiences offer students an opportunity to practice application of knowledge and skills in a safe, risk-free environment and to reflect on the experiences for enhanced learning. An interprofessional collaboration between speech-language pathology and nursing educators facilitated a high-fidelity mannequin simulation with 27 speech-language pathology graduate students. The clinical case evolved over four scenarios requiring a speaking valve assessment, bedside swallow exam (including oral mechanism and cranial nerve exam), and cognitive-speech-language screening in a 3-hour block of time. The focus of this article is to present an introductory template for using high-fidelity mannequin simulations with speech-language pathology graduate students and to encourage use of such methods in collaboration with nursing.

Tris(phosphanylamide) early/late heterobimetallic Zr/Co complexes, ClZr(R′NPR2)3CoI [R′ = iPr, R = Ph (1), R′ = 2,4,6‐trimethylphenyl, R = iPr (2), R′ = R = iPr (3)], have been utilized as catalysts for the cross‐coupling of alkyl halides with n‐octylmagnesium bromide. While yields are consistently higher for alkyl bromide substrates, it is found that these unusual heterobimetallic complexes are also active towards more challenging alkyl chloride substrates. This is particularly interesting in light of the fact that monometallic cobalt complexes are inert towards these substrates, suggesting that Zr also plays a role in catalysis. Radical trapping studies suggest that a one‐electron transfer radical oxidative addition pathway is operative.

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Christine Thomas s'interroge sur l'histoire de la composition des Actes de Pierre. Trois points de vue émergent de la recherche récente: a) des efforts visant à isoler des sources antérieures à la rédaction des Actes apocryphes des apôtres; b) un accent mis sur la libre création romanesque dans la genèse de ces écrits; c) un recours aux théories de la production orale (D. MacDonald, V. Burrus). La thèse de l'auteur est que l'Antiquité est marquée par une coexistence originale entre culture orale et culture écrite et que la composition des Actes de Pierre résulte de l'action combinée de ces deux modes d'expression. A la suite de G. Poupon, le repérage des incohérences narratives l'amène à distinguer deux niveaux dans la rédaction des sources écrites: 1) un auteur réunit en un tout l'histoire de Marcellus, la lutte entre Pierre et Simon et le martyre; 2) un rédacteur introduit ensuite le thème de l'apostasie et de la repentance, ainsi que les références à Paul. Quant à l'influence de la tradition orale sur les Actes de Pierre, elle ressort notamment de la présence de variantes d'un même épisode (histoires de la fille de Pierre et de la fille du jardinier), ou du rappel de la Transfiguration (ch. 20), soulignant que l'évangile écrit ne peut se passer de l'enseignement oral.

The replacement of phosphine substituents in nickel-bound PNNP ligands is reported as an alternative method for preparing multidentate phosphine ligands with alkyl substituents. Treatment of the previously reported bis(phosphide) complex {K(THF)x}22Ph[PNNP]Ni (2) with 2 equiv of MeI, iPrI, and 1,3-dibromoethane formed alkyl-substituted complexes 2Ph,2Me[PNNP]Ni (3), 2Ph,2iPr[PNNP]Ni (4), and 2Ph,propylene[PNNP]Ni (5), respectively. The stereoselectivity (racemic vs meso) of these reactions can be controlled by varying the reaction temperature. The racemic mixtures of products with the new alkyl substituents in an anticonfiguration were favored at lower temperatures, whereas a larger proportion of meso compounds was acquired at higher temperatures. Further treatment of 3with KH resulted in selective elimination of the remaining phenyl groups rather than the methyl substituents, affording bis(methylphosphide) complex {K(THF)x}22Me[PNNP]Ni (6). Subsequent treatment of 6with additional MeI formed 4Me[PNNP]Ni (7), in which all four phenyl groups were replaced with methyl substituents. As a proof of concept, demetalation of the ligand from 7was achieved using aqueous KCN to form a free dimethylphosphine-substituted ligand H24Me[PNNP] (8), and 8was subsequently coordinated to a different metal, using PdCl2to form 4Me[PNNP]Pd (9). Unlike the clean elimination of phenyl substituents from 3, the reactions of KH with 4and 5exhibited competitive elimination of both alkyl and phenyl substituents and/or attenuated reactivity.

The application of a cobalt pincer complex, (PPClP)CoCl2, as a precatalyst for the hydroboration of terminal alkenes with pinacolborane (HBPin) is described. The reactions proceed rapidly under mild conditions (room temperature, 30 min) with low catalyst loadings (1 mol %) using KBEt3H (2.1 mol %) as an activator to afford terminal hydroboration products with very high selectivity for the anti-Markovnikov product. The precatalyst is effective toward vinyl arenes and aliphatic alkenes and proceeds to an 83−98% yield with these substrates. However, the functional group tolerance of the catalytic system is somewhat limited, as minimal conversion is observed with internal olefins or when pyridine, ketone, or allyl ether functional groups are present. Deuterium labeling studies and spectroscopic identification of the catalyst deactivation product suggest a (PPP)CoH active species.

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