Facile, Reversible Hydrogen Activation by Low-Coordinate Magnesium Oxide Complexes.

New approaches to achieve facile and reversible dihydrogen activation are of importance for synthesis, catalysis, and hydrogen storage. Here we show that low-coordinate magnesium oxide complexes [{(nacnac)Mg}(μ-O)] , with nacnac = HC(RCNDip), Dip = 2,6-PrCH, R = Me (), Et (), Pr (), readily react with dihydrogen under mild conditions to afford mixed hydride-hydroxide complexes [{(nacnac)Mg}(μ-H)(μ-OH)] . Dehydrogenation of complexes is strongly dependent on remote ligand substitution and can be achieved by simple vacuum-degassing of (R = Pr) to regain .

Ethyl 4-[(2-hy-droxy-eth-yl)amino]-2-(4-meth-oxyphen-yl)-1-methyl-5-oxo-2,5-di-hydro-1-pyrrole-3-carboxyl-ate.

In the title compound, CHNO the pyrrolidine ring is almost planar and subtends a dihedral angle of 85.77 (7)° with the pendant phenyl ring. An intra-molecular N-H⋯O hydrogen bond generates an (6) loop.

Methyl 2-[()-5-methyl-2-oxoindolin-3-yl-idene]hydrazinecarbodi-thio-ate.

The title di-thio-carbazate imine, CHNOS, was obtained from the condensation reaction of -methyl-dithio-carbazate (SMDTC) and 5-methyl-isatin. It shows a configuration about the imine C=N bond, which is associated with an intra-molecular N-H⋯O hydrogen bond that closes an (6) ring. In the crystal, inversion dimers linked by pairwise N-H⋯O hydrogen bonds generate (8) loops.

Highly Conductive Non-Calcined 2D CuCo Bimetallic-Organic Framework for Urea Electrolysis in Simulated Seawater.

Global clean energy demands can be effectively addressed using the promising approach of hydrogen energy generation combined with less energy consumption. Hydrogen can be generated, and urea-rich wastewater pollution can be mitigated in a low-energy manner using the urea oxidation reaction (UOR). This paper seeks to assemble a unique electrocatalyst of a pristine 2D MOF, [Co(HBTC)(DMF)] (Co-MUM-3), from 1,3,5-benzenetricarboxylate (BTC) to oxidize urea in simulated seawater.

Ethyl (2,3,4)-1-ethyl-2-(furan-2-yl)-4-hy-droxy-5-oxopyrrolidine-3-carboxyl-ate.

The title racemic oxopyrrolidine compound, CHNO, contains three stereogenic centres and crystallizes with two mol-ecules in the asymmetric unit. The five-membered pyrrolidine rings in both mol-ecules exhibit envelope conformations. The -ethyl group of one of the mol-ecules is disordered over two sets of sites in a 0.

Synthesis of Janus All- Tetrafluorocyclohexanes Carrying 1,4-Diether Motifs.

Nucleophilic aromatic substitutions (SAr) of alkoxides on pentafluoroaryl ethers are explored as a first step in a synthesis sequence to generate all- 2,3,5,6-tetrafluorocyclohexyl-1,4-dialkyl ethers . The SAr reaction was explored both experimentally and theoretically to rationalize // selectivities. -Butyl deprotection of products followed by phenol alkylations introduces versatility to the synthesis.

Disparities in structural brain imaging in older adults from rural communities in Southern Nevada.

Introduction: Identifying the associations between rural-living or neighborhood disadvantage and neurobiology may clarify rural-urban disparities in older adults with cognitive impairment related to Alzheimer's disease.

Methods: We examined rural-urban differences and neighborhood disadvantages in brain cortical thickness (CT) measures among 71 rural and 87 urban-dwelling older adults. Analysis of covariance was used to test each FreeSurfer-derived CT measures' associations with rural-urban living, clinical impairment status, and their interactions.

Helically chiral multiresonant thermally activated delayed fluorescent emitters and their use in hyperfluorescent organic light-emitting diodes.

Chiral multiresonant thermally activated delayed fluorescence (MR-TADF) materials show great potential as emitters in circularly polarized (CP) organic light-emitting diodes (CP-OLEDs) owing to their bright and narrowband CP emission. Here, two new chiral MR-TADF emitters BuPh-BN and DPA-BuPh-BN possessing intrinsically helical chirality have been synthesized and studied. The large steric interactions between the -butylphenyl groups not only induce the helical chirality but also provide a notable configurational stability to the enantiomers.

Drug Use Patterns in Wastewater and Socioeconomic and Demographic Indicators.

Importance: Measuring drug use behaviors in individuals and across large communities presents substantial challenges, often complicated by socioeconomic and demographic variables.

Objectives: To detect spatial and temporal changes in community drug use by analyzing concentrations of analytes in influent wastewater and exploring their associations with area-based socioeconomic and sociodemographic metrics like the area deprivation index (ADI) and rural-urban commuting area (RUCA) codes.

Design, Setting, And Participants: This longitudinal, cross-sectional wastewater study was performed from May 2022 to April 2023 and included biweekly influent wastewater samples of 39 analytes from 8 sampling locations across 6 wastewater treatment plants in southern Nevada.

Integration of Open Metal Sites in an Amino-Functionalized Sm(III)-Organic Framework toward Enhanced Third-Order Nonlinear Optical Property.

A variety of new inorganic and organic materials have emerged to advance laser technologies and optical engineering. A rational design approach can contribute significantly to fabricating nonlinear optically active metal-organic frameworks (MOFs) by considering the underlying structure-property linkage. Here, it has been embarked on a study of novel samarium(III) MOF, ([Sm(ata)(DMF)]·DMF (ata: 2-aminoterephthalate), abbreviated as NH-Sm-MUM-4) with enhanced nonlinear optical (NLO) properties.

Methyl 2-[()-5-bromo-2-oxoindolin-3-yl-idene]-hydrazinecarbodi-thio-ate.

The title compound, CHBrNOS, a brominated di-thio-carbazate imine deriv-ative, was obtained from the condensation reaction of -methyl-dithio-carbazate (SMDTC) and 5-bromo-isatin. The essentially planar mol-ecule exhibits a configuration, with the di-thio-carbazate and 5-bromo-isatin fragments located on the same sides of the C=N azomethine bond, which allows for the formation of an intra-molecular N-H⋯O (b = bromo-isatin) hydrogen bond generating an (6) ring motif. In the crystal, adjacent mol-ecules are linked by pairs of N-H⋯O hydrogen bonds, forming dimers characterized by an (8) loop motif.

Functional connectivity differences of the olfactory network in Parkinson's Disease, mild cognitive impairment and cognitively normal individuals: A resting-state fMRI study.

Olfactory dysfunction is an early sign of such neurodegenerative diseases as Parkinson's (PD) and Alzheimer's (AD), and is often present in Mild Cognitive Impairment (MCI), a precursor of AD. Understanding neuro-temporal relationships, i.e.

Isothiourea-Catalysed Acylative Kinetic Resolution of Tertiary Pyrazolone Alcohols.

The development of methods for the selective acylative kinetic resolution (KR) of tertiary alcohols is a recognised synthetic challenge with relatively few successful substrate classes reported to date. In this manuscript, a highly enantioselective isothiourea-catalysed acylative KR of tertiary pyrazolone alcohols is reported. The scope and limitations of this methodology have been developed, with high selectivity observed across a broad range of substrate derivatives incorporating varying substitution at N(2)-, C(4)- and C(5)-, as well as bicyclic constraints within the pyrazolone scaffold (30 examples, selectivity factors (s) typically >100) at generally low catalyst loadings (1 mol %).

One-Pot Access to Functionalised Malamides via Organocatalytic Enantioselective Formation of Spirocyclic β-Lactone-Oxindoles and Double Ring-Opening.

Malamides (diamide derivatives of malic acid) are prevalent in nature and of significant biological interest, yet only limited synthetic methods to access functionalised enantiopure derivatives have been established to date. Herein, an effective synthetic method to generate this molecular class is developed through in situ formation of spirocyclic β-lactone-oxindoles (employing a known enantioselective isothiourea-catalysed formal [2+2] cycloaddition of C(1)-ammonium enolates and isatin derivatives) followed by a subsequent dual ring-opening protocol (of the β-lactone and oxindole) with amine nucleophiles. The application of this protocol is demonstrated across twelve examples to give densely functionalised malamide derivatives with high enantio- and diastereo-selectivity (up to >95:5 dr and >99:1 er).

A Mononuclear [PtCl(tpy)]PF Complex for a Yellow Emitting Solution-Processable Organic Light Emitting Diode.

We report square planar mononuclear Pt(II)-complexes of terpyridines in the form of [PtCl(/)]PF as phosphorescent emitters (where = 4-(3-pyridine)2,2':6',2''-terpyridine and = 4'-(3-pyridinyl)-4,4''-di(-butyl)-2,2':6'2''-terpyridine). Complex showed emission at 534 nm in the DCM solution with photoluminescence quantum efficiency (Φ) = 14%, while in the mCBP host (5-wt % doped), the emission shifted to 584 nm with Φ = 37.8% and a phosphorescence lifetime (τ) of 37.

Spirocyclic Pyrrolidinyl Nitroxides with Exo-Methylene Substituents.

Nitroxides are stable organic radicals with exceptionally long lifetimes, which render them uniquely suitable as observable probes or polarising agents for spectroscopic investigation of biomolecular structure and dynamics. Radical-based probes for biological applications are ideally characterized by both robustness towards reductive degradation and beneficial electron spin relaxation parameters. These properties are largely influenced by the molecular structure of the nitroxide scaffold, and also by the conformations it prefers to adopt.

Synthesis and Analysis of (γ,γ',γ''-Trifluoro)neopentyl (TFNP) Aryl Ethers as a Polar Fluoroaliphatic Motif.

A route is developed to (γ,γ',γ'''-trifluoro)neopentyl (TFNP) aryl ethers to extend the methods for the introduction of the tert-butyl group, carrying a fluorine on each of the methyl substituents. The route combines neopentyltosylate 3 with phenols and thiophenols to give efficient substitution reactions to the corresponding TFNP aryl ethers. The three C-F bonds adopt a helical propeller conformation as revealed by computation and single crystal X-ray structure analysis.

A Well-Defined Magnesium Complex of C .

Controlling and understanding charge state and metal coordination in carbon nanomaterials is crucial to harnessing their unique properties. Here we describe the synthesis of the well-defined fulleride complex [{(nacnac)Mg}C], 2, (nacnac)=HC(MeCNMes), Mes=2,4,6-MeCH, from the reaction of the β-diketiminate magnesium(I) complex [{(nacnac)Mg}] with C in aromatic solvents. The molecular structure of complex 2 was determined, providing the first high-quality structural study of a complex with the C ion.

Classifying Alzheimer's Disease Neuropathology Using Clinical and MRI Measurements.

Background: Computer-aided machine learning models are being actively developed with clinically available biomarkers to diagnose Alzheimer's disease (AD) in living persons. Despite considerable work with cross-sectional in vivo data, many models lack validation against postmortem AD neuropathological data.

Objective: Train machine learning models to classify the presence or absence of autopsy-confirmed severe AD neuropathology using clinically available features.

Isothiourea-Catalyzed Enantioselective Functionalisation of Glycine Schiff Base Aryl Esters via 1,6- and 1,4-Additions.

The enantioselective α-functionalisation of glycine Schiff base aryl esters through isothiourea catalysis is successfully demonstrated for 1,6-additions to para-quinone methides (21 examples, up to 95:5 dr and 96:4 er) and 1,4-additions to methylene substituted dicarbonyl or disulfonyl Michael acceptors (17 examples, up to 98:2 er). This nucleophilic organocatalysis approach gives access to a range of α-functionalised α-amino acid derivatives and further transformations of the activated aryl ester group provide a straightforward entry to advanced amino acid-based esters, amides or thioesters.

De-epimerizing DyKAT of β-lactones generated by isothiourea-catalysed enantioselective [2 + 2] cycloaddition.

An enantioselective isothiourea-catalysed [2 + 2] cycloaddition of C(1)-ammonium enolates with pyrazol-4,5-diones is used to construct spirocyclic β-lactones in good yields, excellent enantioselectivity (99 : 1 er) but with modest diastereocontrol (typically 70 : 30 dr). Upon ring-opening with morpholine or alternative nucleophilic amines and alcohols β-hydroxyamide and β-hydroxyester products are generated with enhanced diastereocontrol (up to >95 : 5 dr). Control experiments show that stereoconvergence is observed in the ring-opening of diastereoisomeric β-lactones, leading to a single product (>95 : 5 dr, >99 : 1 er).

Detecting time-varying genetic effects in Alzheimer's disease using a longitudinal genome-wide association studies model.

Introduction: The development and progression of Alzheimer's disease (AD) is a complex process, during which genetic influences on phenotypes may also change. Incorporating longitudinal phenotypes in genome-wide association studies (GWAS) could unmask these genetic loci.

Methods: We conducted a longitudinal GWAS using a varying coefficient test to identify age-dependent single nucleotide polymorphisms (SNPs) in AD.

Alkyl backbone variations in common β-diketiminate ligands and applications to -heterocyclic silylene chemistry.

We report the extension of the common β-diketimine proligand class, nacnacH (HC(RCNAr)H), where R is an alkyl group such as Et or iPr, plus Ph, and Ar is a sterically demanding aryl substituent such as Dip = 2,6-diispropylphenyl, Dep = 2,6-diethylphenyl, Mes = 2,4,6-trimethylphenyl or mesityl, Xyl = 2,6-dimethylphenyl, one-pot condensation procedures. When a condensation reaction is carried out using the chemical dehydrating agent PPSE (polyphosphoric acid trimethylsilylester), β-diketiminate phosphorus(V) products such as (nacnac)PO can also be obtained, which can be converted to the respective proligand nacnacH alkaline hydrolysis. The nacnacH proligands can be converted to their alkali metal complexes with common methods and we have found that deprotonation of nacnacH is significantly more sluggish than that of related β-diketimines with smaller backbone alkyl groups.

Enantioselective Synthesis in Continuous Flow: Polymer-Supported Isothiourea-Catalyzed Enantioselective Michael Addition-Cyclization with α-Azol-2-ylacetophenones.

A packed reactor bed incorporating a polymer-supported isothiourea HyperBTM catalyst derivative has been used to promote the enantioselective synthesis of a range of heterocyclic products derived from α-azol-2-ylacetophenones and -acetamides combined with alkyl, aryl, and heterocyclic α,β-unsaturated homoanhydrides in continuous flow via an α,β-unsaturated acyl-ammonium intermediate. The products are generated in good to excellent yields and generally in excellent enantiopurity (up to 97:3 er). Scale-up is demonstrated on a 15 mmol scale, giving the heterocyclic product in 68% overall yield with 98:2 er after recrystallization.

Poly[3-methyl-pyridinium [(μ-di-hydrogen phosphito)bis(μ-hydrogen phosphito)dizinc]].

In the title compound, {(CHN)[Zn(HPO)(HPO)]}, the constituent ZnO, HPO and HPO polyhedra of the inorganic component are linked into (010) sheets by Zn-O-P bonds (mean angle = 134.4°) and the layers are reinforced by O-H⋯O hydrogen bonds. The protonated templates are anchored to the inorganic sheets bifurcated N-H⋯(O,O) hydrogen bonds.