The Evolution of Dignity: An Intervention Model to Engage and Retain HIV-Positive Black Women in Care.

The Black community is currently battling two pandemics, one is HIV, and the other is COVID-19. Similarly, as with HIV, COVID-19 has shone a spotlight on our healthcare system's structural failings and revealed the disproportionate impact on the Black community, particularly Black women. Black women accounted for the largest proportion of new HIV diagnoses (58 %) among all women in 2018 and represented about one-quarter of new HIV diagnoses among all Black Americans. Additionally, Black women's exposure to an abundance of misinformation about the COVID-19 infection resulted in an increased risk of complications and death from the COVID-19 virus compared to other racial and ethnic groups. Factors that increase HIV transmission risks for Black women include living in poverty, intimate partner violence, and stigma associated with HIV. Moreover, environmental, physical, cultural, financial, social, and psychological barriers are identified as unique challenges for this population's cohort. After being diagnosed with HIV, Black often were unable to access quality HIV care. Access and retention in care are tantamount to the overall well-being of women who are HIV positive. Frequently healthcare providers may attempt to engage and retain patients using only clinical measures. Our non-clinical intervention, The Evolution of Dignity, supports medical outcomes by creating a process that empowers women to motivate themselves toward improved health outcomes while ensuring their engagement and retention in care. Thus, by implementing our comprehensive intervention, all of the necessary elements contributing and promoting improved service utilization and medical adherence are integrated.

2,4,6-Triphenyl-aniline.

Individual mol-ecules of the title compound, C(24)H(19)N, do not participate in hydrogen-bonding inter-actions due to the steric bulk of the phenyl rings ortho to the amine. The dihedral angles between the central ring and the pendant rings are 68.26 (10), 55.28 (10) and 30.61 (11)°.

2,2',5,5'-Tetra-chloro-benzidine.

In the crystal structure of the title compound, C(12)H(8)Cl(4)N(2), mol-ecules lie on crystallographic twofold axes at the centre of the C-C bonds linking the benzene rings, such that the asymmetric unit consists of a half-mol-ecule. The individual mol-ecules participate in inter-molecular N-H⋯N, N-H⋯Cl, C-H⋯Cl and Cl⋯Cl [3.4503 (3) Å] inter-actions.

Guest inclusion and structural dynamics in 2-D hydrogen-bonded metal-organic frameworks.

The structures and dynamic solid-state behavior of four hydrogen-bonded layered metal-organic frameworks are discussed. Three of the complexes incorporate acetone guest molecules between layers; this is attributed to added flexibility in a framework ammonium component. One complex incorporates water guests, in this case an additional -CH(2)OH arm present on the ammonium component accounting for the difference in guest and dynamic behavior. In all four complexes, TGA and XRD show loss and reuptake of water ligands. In the fourth complex, loss of both water guests and water ligands is reversible, with concomitant loss and regeneration of the crystalline structure. This framework flexibility during guest and ligand loss is unprecedented for hydrogen-bonded metal-organic frameworks.

From crystal engineering to cluster engineering: How to transform cadmium chloride from 2-D to 0-D.

The transformation of a 2-D perovskite structure to "expanded" 2-D and finally to a 0-D hexanuclear cadmium chloride cluster by varying the size of substituents on the associated counterions (H vs. methyl vs. ethyl) is described.

Synthesis and Characterization of Cobalt-Cage Complexes with Pendant Phenol Groups.

The synthesis and characterization of four compounds formed from the reductive amination of m- and o-hydroxybenzaldehyde to (1,8-diamino-3,6,10,13,16,19-hexaazabicyclo[6.6.6]eicosane)cobalt(III) are presented. These compounds are the mono- and dialkylated derivatives of the starting cobalt complex. The X-ray crystal structures of each compound, as its fully protonated chloride salt, have been obtained and are reported. The pK(a)'s of the compounds were determined by nonlinear least-squares analysis of data from potentiometric titrations and UV/vis spectrophotometry. The K(a)'s of the phenol groups of the compounds are reduced by roughly 1 order of magnitude compared to their analogous organic phenols. In the solid state, the compounds with one pendant phenol group (2, 4) are yellow and adopt the ob(3) conformation of their ethylene diamine rings in their crystal structures, while the compounds with two pendant phenol groups (3, 5) are orange and have the lel(3) conformation in their crystal structures. Solid-state reflectance UV/vis spectroscopy confirms these structural differences. In water, all four compounds form orange solutions and adopt the lel(3) conformation, as indicated by comparison of UV/vis spectroscopy and cyclic voltammetry properties with the literature.

Synthesis and Characterization of Novel Oxo-Bridged Dinuclear and Hydroxo-Bridged Trinuclear Chromium(III) Assemblies.

The structural and spectroscopic properties of a novel dinuclear chromium-oxo and a trinuclear chromium-hydroxo complex are reported. The dinuclear assembly, [Cr(2)(&mgr;-O)(2)(&mgr;-O(2)CMe)(bpy)(2)(H(2)O)(2)]ClO(4).bpy.[bpyH]ClO(4) (1), crystallizes in the monoclinic space group Cc with a = 16.8259(8) Å, b = 21.9622(11) Å, c = 14.6056(8) Å, beta = 122.1830(10) degrees, V = 4568.0(4) Å(3), and Z = 4. The structure was refined with 4378 observed reflections having F > 2.0sigma(F), giving final R factors of 0.0721 and 0.1305 for R and R(w2), respectively. The [Cr(2)(&mgr;-O)(2)(&mgr;-O(2)CMe)](+) core is structurally akin to those of recently reported isoelectronic [Mn(2)(&mgr;-O)(2)(&mgr;-O(2)CMe)](3+) complexes. The trinuclear assembly, [Cr(3)(&mgr;-OH)(2)(&mgr;-O(2)CMe)(4)(O(2)CMe)(2)(bpy)(2)]ClO(4) (2).5CHCl(3) crystallizes in the triclinic space group P&onemacr; with a = 16.104(5) Å, b = 17.623(5) Å, c = 12.236(3) Å, alpha = 93.33(1) degrees, beta = 92.81(1) degrees, gamma = 64.84(1) degrees, V = 3136.68 Å(3), and Z = 2. The structure was refined with 6732 observed reflections having F > 2.33sigma(F), giving final R factors of 0.0602 and 0.0616 for R and R(w), respectively. Results of electronic, (1)H and (2)H NMR, and EPR spectroscopy, fast atom bombardment mass spectrometry, and variable-temperature magnetic susceptibility studies of these materials and the use of Cr-oxo assemblies as isoelectronic models of the photosynthetic manganese assembly in high-S states are discussed.

"Total Synthesis" Supramolecular Style: Design and Hydrogen-Bond-Directed Assembly of Ternary Supermolecules.

Getting the right balance between intermolecular interactions is crucial for the synthesis of supermolecules in a preconceived manner. The three-component supermolecule in the ternary cocrystal of 3,5-dinitrobenzoic acid, isonicotinamide, and 4-(dimethylamino)benzoic acid (1:1:1) assembles through a "primary" (between the stronger acid and pyridine) and a "secondary" hydrogen-bonding interaction (between the weaker acid and amide).

A Versatile Route to Porous Solids: Organic-Inorganic Hybrid Materials Assembled through Hydrogen Bonds.

Square-planar and octahedral complexes of NiII and PtII link through head-to-head hydrogen bonds to form porous frameworks with large cavities that are suitable for inclusion of guest molecules. A series of four different complexes with pyridine-based ligands (in the center of the picture) are described, which contain either counterions or small molecules in channels. A=hydrogen-bond acceptor, D=hydrogen-bond donor, M=metal ion.

Properties of a mixed-valence (Fe(II))2(Fe(III))2 square cell for utilization in the quantum cellular automata paradigm for molecular electronics.

The di-mixed-valence complex [{(eta(5)-C5H5)Fe(eta(5)-C5H4)}4(eta(4)-C4)Co(eta(5)-C5H5)]2+, 1(2+), has been evaluated as a molecular four-dot cell for the quantum cellular automata paradigm for electronic devices. The cations 1(1+) and 1(2+) are prepared in good yield by selective chemical oxidation of 1(0) and are isolated as pure crystalline materials. The solid-state structures of 1(0) and 1(1+) and the midrange- and near-IR spectra of 1(0), 1(1+), 1(2+), and 1(3+) have been determined. Further, the variable-temperature EPR spectra of 1(1+) and 1(2+), magnetic susceptibility of 1(1+) and 1(2+), Mössbauer spectra of 1(0), 1(1+), and 1(2+), NMR spectra of 1(0), and paramagnetic NMR spectra of 1(1+) and 1(2+) have been measured. The X-ray structure determination reveals four ferrocene "dots" arranged in a square by C-C bonds to the corners of a cyclobutadiene linker. The four ferrocene units project from alternating sides of the cyclobutadiene ring and are twisted to minimize steric interactions both with the Co(eta(5)-C5H5) fragment and with each other. In the solid state 1(2+) is a valence-trapped Robin and Day class II compound on the 10(-12) s infrared time scale, the fastest technique used herein, and unambiguous evidence for two Fe(II) and two Fe(III) sites is observed in both the infrared and Mössbauer spectra. Both EPR and magnetic susceptibility measurements show no measurable spin-spin interaction in the solid state. In solution, the NMR spectra show that free rotation around the C-C bonds connecting the ferrocene units to the cyclobutadiene ring becomes increasingly hindered with decreasing temperature, leading to spectra at the lowest temperature that are consistent with the solid-state structure. Localization of the charges in the cations, which is observed in the paramagnetic NMR spectra as a function of temperature, correlates with the fluxional behavior. Hence, the alignment between the pi systems of the central linker and the ferrocene moieties most likely controls the rate of electron exchange between the dots.

Molecular recognition of trigonal oxyanions using a ditopic salt receptor: evidence for anisotropic shielding surface around nitrate anion.

A ditopic, macrobicyclic receptor with adjacent anion and cation binding sites is able to extract a range of monovalent salts into chloroform solution. The structures of the receptor complexed with KAcO, LiNO(3), NaNO(3), KNO(3), and NaNO(2) are characterized in solution by NMR spectroscopy and in the solid state by X-ray crystallography. The sodium and potassium salts are bound to the receptor as contact ion-pairs, with the metal cation located in the receptor's crown ether ring and the trigonal oxyanion hydrogen bonded to the receptor NH residues. The solid-state structure of the LiNO(3) complex has a bridging water molecule between the cation and anion. In all solid-state structures, the trigonal oxyanion is not located symmetrically inside the receptor cavity. It appears that anion orientation is controlled by a complex interplay of steric factors, coordination bonding to the metal cation, and hydrogen bonding with the receptor NH residues. An important feature with this latter effect is the fact that hydrogen bonds directed toward the oxygen lone pairs on a trigonal oxyanion are stronger than hydrogen bonds to the pi-electrons. In solution, the (1)H NMR spectra of the nitrate and nitrite salt complexes are noteworthy because several receptor signals, including the NH protons, undergo unusual upfield movements in chemical shift upon complexation. This is a reflection of the diamagnetic anisotropy of these trigonal oxyanions. The magnetic shielding surface for the NO(3)(-) anion is calculated using density functional theory and shown to have a shielding region directly above the central nitrogen.

Ruthenacarboranes from the reaction of nido-1,2-(Cp*RuH)2B3H7 with HC [triple bond] CCO2Me, Cp* = eta5-C5Me5. Hydrometalation, alkyne incorporation, and functional group modification via cooperative metal-boron interactions within a metallaborane cluster framework.

Reaction of nido-1,2-(Cp*RuH)2B3H7, 1, and methyl acetylene monocarboxylate under kinetic control generates nido-1,2-(Cp*Ru)2(mu-C[[CO2Me]Me])B3H7 (a pair of geometric isomers, 3 and 5) and nido-1,2-(Cp*Ru)2(1,3-mu-C[[CH2CO2Me]H])B3H7, 4, which display the first examples of exo-cluster mu-alkylidene Ru-B bridges generated by hydrometalation of an alkyne on the cluster framework. Both 3 and 5, but not 4, rearrange into arachno-2,8-mu(C)-5-eta1(O)-Me[CO2Me]C-1,2-(Cp*Ru)2B3H7, 2, in which an unprecedented intramolecular coordination of the carbonyl oxygen atom of the alkyne substituent to a boron framework site opens the ruthenaborane skeleton. Compound 2, in turn, is an intermediate in the formation of the ruthenacarborane nido-1,2-(Cp*Ru)2-3-OH-4-OMe-5-Me-4,5-C2B2H5, 12, in which the carbonyl-oxygen double bond has been cleaved as its oxygen atom inserts into a B-H bond and the carbonyl carbon inserts into the metallaborane framework. In a parallel reaction pathway, nido-1,2-(Cp*Ru)2-5-CO2Me-4,5-C2B2H7, 6, nido-1,2-(Cp*Ru)2-4-B(OH)2-5-CO2Me-4,5-C2B2H6, 16, and nido-1,2-(Cp*Ru)2(mu-H)(mu-BH2)-3-(CH2)2CO2Me-CO2Me-4,5-C2B2H4 (a pair of geometric isomers, 7 and 14, which contain an unusual Ru-B borane bridge) are formed. On heating, 7 rearranges to yield nido-1,2-(Cp*Ru)2-3-(CH2)2CO2Me-4-BH2-5-CO2Me-4,5-C2B2H5, 13, whereas 14 converts to nido-1,2-(Cp*Ru)2-3-(CH2)2CO2Me-4-CO2Me-4,5-C2B2H6, 8. Under thermodynamic control, nido-1,2-(Cp*Ru)2-4,5-B[(CH2)2CO2Me]CO(MeO)[C(CH2)CO2Me]-4,5-C2B2H6, 11, is the major product accompanied by lesser amounts of 6 and 1,2-(Cp*Ru)2-4-OMe-5-Me-4,5-C2B2H6, 10. Compound 11 features a five-membered heterocycle containing a boron atom. The structure of 7, which is an intermediate in the formation of 11, provides the basis for an explanation of this complex condensation of three alkynes. A previously unrecognized role for an exo-cluster bridging borene generated from the metallaborane skeleton by addition of the alkyne is also a feature of this chemistry. Reinsertion or loss of this boron fragment accounts for much of the chemistry observed. NMR experiments reveal labile intermediates, and one has been sufficiently characterized to provide mechanistic insight on the early stages of the alkyne-metallaborane addition reaction. All isolated compounds have been spectroscopically characterized, and most have been structurally characterized in the solid state.

A high-yielding supramolecular reaction.

The X-ray crystal structure determinations of twelve cocrystals involving iso-nicotinamide and a variety of carboxylic acids have revealed a very consistent pattern of hydrogen-bond preferences. The combination of a monocarboxylic acid, an amide, and a pyridine moiety leads, in every case, to discrete "supermolecules" (consisting of two molecules of iso-nicotinamide and two molecules of the relevant carboxylic acid) with well-defined and robust connectivity. The two dominant (regularly occurring) supramolecular synthons in these crystal structures are (1) the heteromeric carboxylic acid.pyridine hydrogen bond and (2) a self-complementary amide.amide hydrogen-bond interaction, both of which prevail in the presence of widely differing chemical functionalities. In four of these cocrystals, a dicarboxylic acid is employed, which alters the structural outcome from discrete entities to infinite assemblies (or to a hexameric complex in a "U-shaped" dicarboxylic acid), which is fully expected since the two primary supramolecular synthons remain intact. This structural study shows that iso-nicotinamide is a supramolecular reagent that can produce well-defined supermolecules (containing carboxylic acids) in very high yields.

Facile hydrometalation of alkynes by nido-1,2-(CpRuH)(2)B(3)H(7) yielding novel Ru-B edge-bridging alkylidenes. Stepwise conversion of HCtbd1;CC(O)OMe into nido-1,2-(CpRuH)(2)-3-HOB-4-MeC-5-MeOC-BH(3), Cp = eta(5)-C(5)Me(5).

The reaction of the alkyne HCCC(O)OMe with 7 sep 1,2-(Cp*RuH)2B3H7 leads to hydroboration plus hydroruthenation to produce nido-1,3-mu-Me{C(O)OMe}C-1,2-(Cp*Ru)2B3H7, a compound with an exocluster ruthenium-boron mu-alkylidene that exists in two isomeric forms. Both isomers undergo rearrangement with intramolecular chelation of the carbonyl oxygen at a boron site, thereby opening the cluster and generating arachno-2,3,-mu(C)-5-eta1(O)-Me{C(O)OMe}C-1,2-(Cp*Ru)2B3H7. Further heating leads to deoxygenation of the carbonyl fragment by a boron center concurrent with insertion of the carbon atom into the metallaborane cage to give nido-1,2-(Cp*RuH)2-3-HOB-4-MeC-5-MeOC-BH3.

Molecular QCA cells. 1. Structure and functionalization of an unsymmetrical dinuclear mixed-valence complex for surface binding.

Utilization of binary information encoded in the charge configuration of quantum-dot cells (the quantum-dot cellular automata, QCA, paradigm) requires molecule-sized dots for room temperature operation. Molecular QCA cells are mixed-valence complexes, and the evaluation and functionalization of an unsymmetrical heterobinuclear, two-dot, Fe-Ru molecular QCA cell is described. The solid state structures of trans-RuCl(dppm)(2)(C[triple bond]CFc) (1) (dppm = methylbis(diphenylphosphane), Fc = (eta(5)-C(5)H(5))Fe(eta(5)-C(5)H(4))) and mixed-valence [trans-RuCl(dppm)(2)(C[triple bond]CFc)][BF(4)] (1a) as well as XPS and spectroscopic data suggest class II behavior suitable for the intended application. Utilization of the trans-Cl position of 1 permits functionalization for surface binding. Two "tailed" complexes of 1, trans-Ru(dppm)(2)(C[triple bond]CFc)(C[triple bond]CPhOCH(3)) (2) and trans-[Ru(dppm)(2)(C[triple bond]CFc)(N[triple bond]CCH(2)CH(2)NH(2))][PF(6)] (3), have been prepared and characterized. The solid state structure of 3 and multinuclear NMR experiments define the structures. In addition, the spectroscopic properties of all complexes and their mixed-valence species are used to define the effect of the substituent "tail" on mixed-valence properties. Further, the electrochemistry of these compounds permits assessment of the extent of perturbation of the substituents on the comproportionation constants and overall electrochemical stability. The complexes possess properties necessary for candidate QCA molecules.

Selective solid-liquid extraction of lithium halide salts using a ditopic macrobicyclic receptor.

A ditopic salt receptor that is known to bind and extract solid NaCl, KCl, NaBr, and KBr into organic solution as their contact ion pairs is now shown by NMR and X-ray crystallography to bind and extract solid LiCl and LiBr as water-separated ion pairs. The receptor can transport these salts from an aqueous phase through a liquid organic membrane with a cation selectivity of K+ > Na+ > Li+. However, the selectivity order is strongly reversed when the receptor extracts solid alkali metal chlorides and bromides into organic solution. For a three-component mixture of solid LiCl, NaCl, and KCl, the ratio of salts extracted and complexed to the receptor in CDCl3 was 94:4:2, respectively. The same strong lithium selectivity was also observed in the case of a three-component mixture of solid LiBr, NaBr, and KBr where the ratio of extracted salts was 92:5:3. This observation is attributed to the unusually high solubility of lithium salts in organic solvents. The study suggests that ditopic receptors with an ability to extract solid salts as associated ion pairs may have application in separation processes.