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Shortwave infrared (SWIR, 1000-1700 nm) and extended SWIR (ESWIR, 1700-2700 nm) absorbing materials are valuable for applications including fluorescence based biological imaging, photodetectors, and light emitting diodes. Currently, ESWIR absorbing materials are largely dominated by inorganic semiconductors which are often costly both in raw materials and manufacturing processes used to produce them. The development of ESWIR absorbing organic molecules is thus of interest due to the tunability, solution processability, and low cost of organic materials compared to their inorganic counterparts. Herein, through the combination of heterocyclic indolizine donors and an antiaromatic fluorene core, a series of organic chromophores with absorption maxima ranging from 1470-2088 nm (0.84-0.59 eV) and absorption onsets ranging from 1693-2596 nm (0.73-0.48 eV) are designed and synthesized. The photophysical and electrochemical properties of these chromophores, referred to as FluIndz herein, are described via absorption spectroscopy in 17 solvents, cyclic voltammetry, solution photostability, and transient absorption spectroscopy. Molecular orbital energies, predicted electronic transitions, and antiaromaticity are compared to higher energy absorbing chromophores using density functional theory. The presence of thermally accessible diradical states is demonstrated using density functional theory and EPR spectroscopy, while XRD crystallography confirms structural connectivity and existence as a single molecule. Overall, the FluIndz chromophore scaffold exhibits a rational means to access organic chromophores with extremely narrow optical gaps., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Tetraceno[2,3- b ]thiophene is regarded as a strong candidate for singlet fission-based solar cell applications due to its mixed characteristics of tetracene and pentacene that balance exothermicity and triplet energy. An electronically weakly coupled tetraceno[2,3- b ]thiophene dimer (Et 2 Si(TIPSTT) 2 ) with a single silicon atom bridge has been synthesized, providing a new platform to investigate the singlet fission mechanism involving the two acene chromophores. We study the excited state dynamics of Et 2 Si(TIPSTT) 2 by monitoring the evolution of multiexciton coupled triplet states, 1 TT to 5 TT to 3 TT to T 1 + S 0 , upon photoexcitation with transient absorption, temperature-dependent transient absorption, and transient/pulsed electron paramagnetic resonance spectroscopies. We find that the photoexcited singlet lifetime is 107 ps, with 90% evolving to form the TT state, and the complicated evolution between the multiexciton states is unraveled, which can be an important reference for future efforts toward tetraceno[2,3- b ]thiophene-based singlet fission solar cells.

Syntheses of the acyclic amidinium salts, morpholino-formamidinium hexa-fluorido-phosphate [OC 4 H 8 N-CH=NH 2 ]PF 6 or C 5 H 11 N 2 O + ·PF 6 - , 1 , and pyrrolidinoformamidinium hexa-fluorido-phosphate [C 4 H 8 N-CH= NH 2 ]PF 6 or C 5 H 11 N 2 + ·PF 6 - , 2 , were carried out by heating either morpholine or pyrrolidine with triethyl orthoformate and ammonium hexa-fluorido-phosphate. Crystals of 1 obtained directly from the reaction mixture contain one cation and one anion in the asymmetric unit. The structure involves cations linked in chains parallel to the b axis by N-H⋯O hydrogen bonds in space group Pbca , with glide-related chains pointing in opposite directions. Crystals of 1 obtained by recrystallization from ethanol, however, showed a similar unit cell and the same basic structure, but unexpectedly, there was positional disorder [occupancy ratio 0.639 (4):0.361 (4)] in one of the cation chains, which lowered the crystal symmetry to the non-centrosymmetric space group Pca2 1 , with two cations and anions in the asymmetric unit. In the pyrrolidino compound, 2 , cations and anions are ordered and are stacked separately, with zigzag N-H⋯F hydrogen-bonding between stacks, forming ribbons parallel to (101), extended along the b -axis direction. Slight differences in the delocalized C=N distances between the two cations may reflect the inductive effect of the oxygen atom in the morpholino compound., (© Neary et al. 2024.)

To improve the charge-carrier transport capabilities of thin-film organic materials, the intermolecular electronic couplings in the material should be maximized. Decreasing intermolecular distance while maintaining proper orbital overlap in highly conjugated aromatic molecules has so far been a successful way to increase electronic coupling. We attempted to decrease the intermolecular distance in this study by synthesizing cocrystals of simple benzoic acid coformers and dipyridyl-2,2'-bithiophene molecules to understand how the coformer identity and pyridine N atom placement affected solid-state properties. We found that with the 5-(3-pyridyl)-5'-(4-pyridyl)-isomer, the 4-pyridyl ring interacted with electrophiles and protons more strongly. Synthesized cocrystal powders were found to have reduced average crystallite size in reference to the parent compounds. The opposite was found for the intermolecular electronic couplings, as determined via density functional theory (DFT) calculations, which were relatively large in some of the cocrystals., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Photoreactive Ru(II) complexes capable of ejecting ligands have been used extensively for photocaging applications and for the creation of "photocisplatin" reagents. The incorporation of distortion into the structure of the coordination complex lowers the energy of dissociative excited states, increasing the yield of the photosubstitution reaction. While steric clash between ligands induced by adding substituents at the coordinating face of the ligand has been extensively utilized, a lesser known, more subtle approach is to distort the coordination sphere by altering the chelate ring size. Here a systematic study was performed to alter metal-ligand bond lengths, angles, and to cause intraligand distortion by introducing a "linker" atom or group between two pyridine rings. The synthesis, photochemistry, and photobiology of five Ru(II) complexes containing CH 2 , NH, O, and S-linked dipyridine ligands was investigated. All systems where stable in the dark, and three of the five were photochemically active in buffer. While a clear periodic trend was not observed, this study lays the foundation for the creation of photoactive systems utilizing an alternative type of distortion to facilitate photosubstitution reactions., Competing Interests: Declaration of Competing Interest Edith Glazer reports financial support was provided by National Institutes of Health., (Copyright © 2022. Published by Elsevier Inc.)

Co-crystallization of N -(4-meth-oxy-phen-yl)piperazine with 4-methyl-benzoic acid and with benzene-1,2-di-carb-oxy-lic acid yields the salts 4-(4-meth-oxy-phen-yl)piperazin-1-ium 4-methyl-benzoate monohydrate, C 11 H 17 N 2 O + ·C 8 H 7 O 2 - ·H 2 O (I), and bis-[4-(4-meth-oxy-phen-yl)piperazin-1-ium] benzene-1,2-di-carboxyl-ate, 2C 11 H 17 N 2 O + ·C 8 H 4 O 4 2- (II). These salts both crystallize with Z ' = 2, in space groups P and Pna 2 1 , respectively. In compound (I), a combination of four O-H⋯O, four N-H⋯O, one C-H⋯O and one C-H⋯π(arene) hydrogen bonds link the six independent components into complex sheets, within which the two piperazine rings, the two anions, and the two water mol-ecules are related by an approximate, non-crystallographic translation along the b -axis direction. In compound (II), sheets containing R 4 4 (18) and R 10 12 (38) rings are formed by the combined action of eight independent N-H⋯O hydrogen bonds. Comparisons are made with the structures of some related compounds., (© Shankara Prasad et al. 2022.)

Crystal structures are reported for two mol-ecular salts containing the 4-(4-nitro-phen-yl)piperazin-1-ium cation. Co-crystallization from methanol/ethyl acetate solution of N -(4-nitro-phen-yl)piperazine with benzoic acid gives the benzoate salt, which crystallizes as a monohydrate, C 10 H 14 N 3 O 2 ·C 7 H 5 O 2 ·H 2 O, (I), and similar co-crystallization with 3,5-di-nitro-salicylic acid yields the 2-carb-oxy-4,6-di-nitro-phenolate salt, C 10 H 14 N 3 O 2 ·C 7 H 3 N 2 O 7 , (II). In the structure of (I), a combination of O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds links the components into sheets, while in the structure of (II), the supra-molecular assembly, generated by hydrogen bonds of the same types as in (I), is three dimensional. Comparisons are made with the structures of some related compounds., (© Shankara Prasad et al. 2022.)

Twinning by pseudo-merohedry is a common phenomenon in small-mol-ecule crystallography. In cases where twin-component volume fractions are markedly different, structure solution is often no more difficult than for non-twinned structures of similar complexity. When twin-component volume fractions are similar, however, structure solution can be much more of a problem. This paper presents hints and tips for such cases by means of three worked examples. The first example presents the most common (and simplest) case of a two-component pseudo-ortho-rhom-bic twin. The second example describes structure solution of a reticular threefold pseudo-hexa-gonal twin that benefits from use of an unconventional space-group setting. The third example covers structure solution of a reticular fourfold pseudo-tetra-gonal twin. All three structures are ultimately shown to be monoclinic crystals that twin as a consequence of unit-cell metrics that mimic those of higher symmetry crystal systems., (© S. R. Parkin 2021.)

Herein is reported the synthesis of two Au(III) complexes bearing the ( R , R )-(-)-2,3-Bis( tert -butylmethylphosphino)quinoxaline ( R , R -QuinoxP*) or ( S , S )-(+)-2,3-Bis( tert -butylmethylphosphino)quinoxaline ( S,S -QuinoxP*) ligands. By reacting two stoichiometric equivalents of HAuCl 4 .3H 2 O to one equivalent of the corresponding QuinoxP* ligand, ( R , R )-(-)-2,3-Bis( tert -butylmethylphosphino)quinoxalinedichlorogold(III) tetrachloroaurates(III) ( 1 ) and ( S , S )-(+)-2,3-Bis( tert -butylmethylphosphino)quinoxalinedichlorogold(III) tetrachloroaurates(III) ( 2 ) were formed, respectively, in moderate yields. The structure of ( S , S )-(+)-2,3-Bis( tert -butylmethylphosphino)quinoxalinedichlorogold(III) tetrachloroaurates(III) ( 2 ) was further confirmed by X-ray crystallography. The antiproliferative activities of the two compounds were evaluated in a panel of cell lines and exhibited promising results comparable to auranofin and cisplatin with IC 50 values between 1.08 and 4.83 µM. It is noteworthy that in comparison to other platinum and ruthenium enantiomeric complexes, the two enantiomers ( 1 and 2 ) do not exhibit different cytotoxic effects. The compounds exhibited stability in biologically relevant media over 48 h as well as inert reactivity to excess glutathione at 37 °C. These results demonstrate that the Au(III) atom, stabilized by the QuinoxP* ligand, can provide exciting compounds for novel anticancer drugs. These complexes provide a new scaffold to further develop a robust and diverse library of chiral phosphorus Au(III) complexes.

Attempts to functionalize polycyclic quinones using lithium diisopropylamide as a base led to the unexpected formation of acenes. This reaction proceeds by electron transfer from the base to the electron deficient quinone, whose radical anion can react with a variety of electrophiles. Siloxy derivatives synthesized by this method could be easily isolated but showed poor photostability. In situ reduced intermediate generation is a convenient approach to functionalization of oxidatively unstable hydroquinones.

Androgen-deprivation therapy (ADT) is only a palliative measure, and prostate cancer invariably recurs in a lethal, castration-resistant form (CRPC). Prostate cancer resists ADT by metabolizing weak, adrenal androgens to growth-promoting 5α-dihydrotestosterone (DHT), the preferred ligand for the androgen receptor (AR). Developing small-molecule inhibitors for the final steps in androgen metabolic pathways that utilize 17-oxidoreductases required probes that possess fluorescent groups at C-3 and intact, naturally occurring functionality at C-17. Application of the Pictet-Spengler condensation to substituted 4-(2-aminoethyl)coumarins and 5α-androstane-3-ones furnished spirocyclic, fluorescent androgens at the desired C-3 position. Condensations required the presence of activating C-7 amino or N,N-dialkylamino groups in the 4-(2-aminoethyl)coumarin component of these condensation reactions. Successful Pictet-Spengler condensation, for example, of DHT with 9-(2-aminoethyl)-2,3,6,7-tetrahydro-1H,5H,11H-pyrano[2,3-f]pyrido[3,2,1-ij]quinolin-11-one led to a spirocyclic androgen, (3R,5S,10S,13S,17S)-17-hydroxy-10,13-dimethyl-1,2,2',3',4,5,6,7,8,8',9,9',10,11,12,12',13,13',14,15,16,17-docosahydro-7'H,11'H-spiro-[cyclopenta[a]phenanthrene-3,4'-pyrido[3,2,1-ij]pyrido[4',3':4,5]pyrano[2,3-f]quinolin]-5'(1'H)-one. Computational modeling supported the surrogacy of the C-3 fluorescent DHT analog as a tool to study 17-oxidoreductases for intracrine, androgen metabolism., Competing Interests: Conflicts of interest CL and DSW have partial ownership in a for-profit venture, Epionc, Inc., that seeks to develop small-molecule inhibitors for cancer treatment. In accord with University of Kentucky policies, CL and DSW have disclosed this work to the University of Kentucky’s Intellectual Property Committee and to a Conflict of Interest Oversight Committee.

Polychlorinated biphenyls (PCBs) are environmental pollutants implicated in a variety of adverse health effects, including cancer and noncancer diseases in animals and humans. PCBs are metabolized to hydroxylated compounds, and some of these PCB metabolites are more toxic than the parent PCBs. Unfortunately, most PCB metabolites needed for toxicological studies are not available from commercial sources. Moreover, it is challenging to synthesize PCB metabolites because starting materials with suitable substitution patterns are not readily available. Here, we report the novel synthesis of a variety of mono- and dimethoxyarene derivatives from commercially available fluoroarenes via nucleophilic aromatic substitution with sodium methoxide. This reaction provided good to excellent yields of the desired methoxylated products. Suzuki coupling of selected mono- and dimethoxy haloarenes with chlorinated phenylboronic acids yielded methoxylated derivatives of PCB 11, 12, 25, 35, and 36 in low to good yields. Crystal structures of 3,3'-dichloro-2,5-dimethoxy-1,1'-biphenyl and 3',5-dichloro-2,3-dimethoxy-1,1'-biphenyl confirmed the substitution pattern of both compounds. This synthesis strategy provides straightforward access to a range of mono- and dimethoxylated PCB derivatives that were not readily accessible previously.

The title compound [systematic name: (1 R *, 8 S )-2-acetamidoocta-hydro-pyrrol-izin-4-ium chloride- N -[(1 R , 8 S )-hexa-hydro-1 H -pyrrolizin-2-yl)acetamide (1/1)], 2(C 9 H 16 N 2 O)·HCl or C 9 H 17 N 2 O + ·Cl - ·C 9 H 16 N 2 O, arose as an unexpected product when 1- exo -acetamido-pyrrolizidine (AcAP; C 9 H 16 N 2 O) was dissolved in CHCl 3 . Within the AcAP pyrrolizidine group, the unsubstituted five-membered ring is disordered over two orientations in a 0.897 (5):0.103 (5) ratio. Two AcAP mol-ecules related by a crystallographic twofold axis link to H + and Cl - ions lying on the rotation axis, thereby forming N-H⋯N and N-H⋯Cl⋯H-N hydrogen bonds. The first of these has an unusually short N⋯N separation of 2.616 (2) Å: refinement of different models against the present data set could not distinguish between a symmetrical hydrogen bond (H atom lying on the twofold axis and equidistant from the N atoms) or static or dynamic disorder models ( i.e. N-H⋯N + N⋯H-N). Computational studies suggest that the disorder model is slightly more stable, but the energy difference is very small., (© Bhardwaj et al. 2020.)

Herein, we describe the design and synthesis of a suite of molecules based on a benzodithiophene "universal crystal engineering core". After computationally screening derivatives, a trialkylsilylethyne-based crystal engineering strategy was employed to tailor the crystal packing for use as the active material in an organic field-effect transistor. Electronic structure calculations were undertaken to reveal derivatives that exhibit exceptional potential for high-efficiency hole transport. The promising theoretical properties are reflected in the preliminary device results, with the computationally optimized material showing simple solution processing, enhanced stability, and a maximum hole mobility of 1.6 cm 2 V -1 s -1 ., (This journal is © The Royal Society of Chemistry 2019.)

Imidazolium salts are common building blocks for functional materials and in the synthesis of N-heterocyclic carbene (NHC) as σ-donor ligands for stable metal complexes. The title salt, 1,3-bis-(4-hy-droxy-phen-yl)-1 H -imidazol-3-ium chloride (IOH·Cl), C 15 H 13 N 2 O 2 + ·Cl - , is a new imidazolium salt with a hy-droxy functionality. The synthesis of IOH·Cl was achieved in high yield via a two-step procedure involving a di-aza-butadiene precursor followed by ring closure using tri-methylchloro-silane and paraformaldehyde. The structure of IOH·Cl consists of a central planar imidazolium ring (r.m.s. deviation = 0.0015 Å), with out-of-plane phenolic side arms. The dihedral angles between the 4-hy-droxy-phenyl substituents and the imidazole ring are 55.27 (7) and 48.85 (11)°. In the crystal, O-H⋯Cl hydrogen bonds connect the distal hy-droxy groups and Cl - anions in adjacent asymmetric units, one related by inversion (- x  + 1, - y  + 1, - z  + 1) and one by the n -glide ( x  - , - y  + , z  - ), with donor-acceptor distances of 2.977 (2) and 3.0130 (18) Å, respectively. The phenolic rings are each π-π stacked with their respective inversion-related [(- x  + 1, - y  + 1, - z  + 1) and (- x , - y  + 1, - z  + 1)] counterparts, with inter-planar distances of 3.560 (3) and 3.778 (3) Å. The only other noteworthy inter-molecular inter-action is an O⋯O (not hydrogen bonded) close contact of 2.999 (3) Å between crystallographically different hy-droxy O atoms on translationally adjacent mol-ecules ( x  + 1, y , x  + 1).

The structure of zymonic acid (systematic name: 4-hy-droxy-2-methyl-5-oxo-2,5-di-hydro-furan-2-carb-oxy-lic acid), C 6 H 6 O 5 , which had previously eluded crystallographic determination, is presented here for the first time. It forms by intra-molecular condensation of parapyruvic acid, which is the product of aldol condensation of pyruvic acid. A redetermination of the crystal structure of pyruvic acid (systematic name: 2-oxo-propanoic acid), C 3 H 4 O 3 , at low temperature (90 K) and with increased precision, is also presented [for the previous structure, see: Harata et al. (1977 ▸). Acta Cryst. B 33 , 210-212]. In zymonic acid, the hy-droxy-lactone ring is close to planar (r.m.s. deviation = 0.0108 Å) and the dihedral angle between the ring and the plane formed by the bonds of the methyl and carb-oxy-lic acid carbon atoms to the ring is 88.68 (7)°. The torsion angle of the carb-oxy-lic acid group relative to the ring is 12.04 (16)°. The pyruvic acid mol-ecule is almost planar, having a dihedral angle between the carb-oxy-lic acid and methyl-ketone groups of 3.95 (6)°. Inter-molecular inter-actions in both crystal structures are dominated by hydrogen bonding. The common R 2 2 (8) hydrogen-bonding motif links carb-oxy-lic acid groups on adjacent mol-ecules in both structures. In zymonic acid, this results in dimers about a crystallographic twofold of space group C 2/ c , which forces the carb-oxy-lic acid group to be disordered exactly 50:50, which scrambles the carbonyl and hydroxyl groups and gives an apparent equalization of the C-O bond lengths [1.2568 (16) and 1.2602 (16) Å]. The other hydrogen bonds in zymonic acid (O-H⋯O and weak C-H⋯O), link mol-ecules across a 2 1 -screw axis, and generate an R 2 2 (9) motif. These hydrogen-bonding inter-actions propagate to form extended pleated sheets in the ab plane. Stacking of these zigzag sheets along c involves only van der Waals contacts. In pyruvic acid, inversion-related mol-ecules are linked into R 2 2 (8) dimers, with van der Waals inter-actions between dimers as the only other inter-molecular contacts.

Purpose: A cost-reduction strategy for isoproterenol use in radiofrequency catheter ablation procedures was evaluated., Summary: A medication-use evaluation at a 454-bed tertiary medical center revealed that the cardiac catheterization laboratory was the highest user of isoproterenol. Isoproterenol was removed from all AcuDose-Rx machines Omnicell, Mountain View, CA, and compounding was performed by pharmacy personnel. It was initially provided to the cardiac catheterization laboratory as an 8-µg/mL concentration in 20-mL 0.9% sodium chloride injection syringes with a 24-hour beyond-use date. This resulted in an initial cost savings but with an unacceptably high rate of wastage. Isoproterenol was then compounded as a 4-µg/mL concentration in 30 mL 5% dextrose in water syringes with a 9-day beyond-use date after a thorough literature search supported longer stability with this admixture. After 12 months of our current process, isoproterenol use during radio frequency catheter ablations (RFCAs) in the cardiac catheterization laboratory was reduced by 85%, decreasing the number of ampules used from 11.15 to 1.66 per week., Conclusion: A pharmacy-initiated process to mitigate an extraordinary increase in isoproterenol acquisition cost resulted in a reduction in usage in a tertiary care community hospital. Isoproterenol usage was reduced 85% after two different interventions were implemented, which is estimated to save $1,839 per procedure., (© American Society of Health-System Pharmacists 2019. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Organic semiconducting crystals are characterized by anisotropic optical and electronic properties, which can be tailored by controlling the packing of the constituent molecules in the crystal unit cell. Here, the synthesis, structural characterization, and emission of anthracene derivatives are focused to correlate directed functionalization and optical properties. These compounds are easily and scalably prepared by standard synthesis techniques, and alterations in functional groups yield materials with either exclusive edge-to-face or face-to-face solid-state interactions. The resulting crystals feature either platelet or needle shapes, and the emission exhibits polarization ratios up to 5 at room temperature. In needle-shaped crystals, self-waveguiding of the emission is also observed with propagation loss coefficients as low as 1.3 dB mm -1 . Moreover, optical coupling between crossing crystalline microwires is found and characterized. The combination of optical anisotropy and emission self-waveguiding opens interesting routes for the exploitation of these active materials in photonic applications, including optical integrated circuits and microscale light sources., Competing Interests: The authors declare no competing financial interest.

Molecular engineering strategies designed to red-shift cyanine dye absorptions and emissions further into the near-infrared (NIR) spectral region are explored. Through the use of a novel donor group, indolizine, with varying cyanine bridge lengths, dye absorptions and emissions, were shifted deeper into the NIR region than common indoline-cyanines. Stokes shifts resulting from intramolecular steric interactions of up to ∼60 nm in many cases were observed and explained computationally. Molecular brightnesses of up to 5800 deep into the NIR region were observed. Structure-property relationships are explored for the six indolizine-cyanine dyes with varying cyanine bridge length and indolizine substituents showing broad absorption and emission tunability. The dyes are characterized by crystallography, and the photophysical properties are probed by varying solvent for absorption and emission studies. Computational data show involvement of the entire indolizine π-system during light absorption, which suggests these systems can be tunable even further into the NIR region through select derivatizations.

Client preferences in psychotherapy reflect specific conditions and activities that clients desire in their treatment, with increasing evidence pointing to preference accommodation as facilitating psychotherapy outcomes. This updated meta-analysis establishes the magnitude of the effect of client preference accommodation in psychotherapy. Based on data from 53 studies and over 16,000 clients, preference accommodation was associated with fewer treatment dropouts (OR = 1.79) and more positive treatment outcomes (d = 0.28) than providing client with a nonpreferred treatment or psychotherapy condition. The preference effect was moderated by study design, timing and type of outcome measurement, and client diagnosis. It was not moderated by year of publication, treatment duration, preference type, treatment options, client age, client gender, client ethnicity, or client years of education. The authors provide a case example of preference accommodation and practice recommendations for working with client preferences., (© 2018 Wiley Periodicals, Inc.)

Nineteen polychlorinated biphenyl (PCB) congeners, such as 2,2',3,3',6-pentachlorobiphenyl (PCB 84), display axial chirality because they form stable rotational isomers, or atropisomers, that are non-superimposable mirror images of each other. Although chiral PCBs undergo atropselective biotransformation and atropselectively alter biological processes, the absolute structure of only a few PCB atropisomers has been determined experimentally. To help close this knowledge gap, pure PCB 84 atropisomers were obtained by semi-preparative liquid chromatography with two serially connected Nucleodex β-PM columns. The absolute configuration of both atropisomers was determined by X-ray single-crystal diffraction. The PCB 84 atropisomer eluting first and second on the Nucleodex β-PM column correspond to (aR)-(-)-PCB 84 and (aS)-(+)-PCB 84, respectively. Enantioselective gas chromatographic analysis with the β-cyclodextrin-based CP-Chirasil-Dex CB gas chromatography column showed the same elution order as the Nucleodex β-PM column. Based on earlier reports, the atropisomers eluting first and second on the BGB-172 gas chromatography column are (aR)-(-)-PCB 84 and (aS)-(+)-PCB 84, respectively. An inversion of the elution order is observed on the Cyclosil-B gas chromatography and Cellulose-3 liquid chromatography columns. These results advance the interpretation of environmental and human biomonitoring as well as toxicological studies.

Organometal halide perovskite photovoltaics typically contain both electron and hole transport layers, both of which influence charge extraction and recombination. The ionization energy (IE) of the hole transport layer (HTL) is one important material property that will influence the open-circuit voltage, fill factor, and short-circuit current. Herein, we introduce a new series of triarylaminoethynylsilanes with adjustable IEs as efficient HTL materials for methylammonium lead iodide (MAPbI 3 ) perovskite based photovoltaics. The three triarylaminoethynylsilanes investigated can all be used as HTLs to yield PV performance on par with the commonly used HTLs PEDOT:PSS and Spiro-OMeTAD in inverted architectures (i.e., HTL deposited prior to the perovskite layer). We further investigate the influence of the HTL IE on the photovoltaic performance of MAPbI 3 based inverted devices using two different MAPbI 3 processing methods with a series of 11 different HTL materials, with IEs ranging from 4.74 to 5.84 eV. The requirements for the HTL IE change based on whether MAPbI 3 is formed from lead acetate, Pb(OAc) 2 , or PbI 2 as the Pb source. The ideal HTL IE range is between 4.8 and 5.3 eV for MAPbI 3 processed from Pb(OAc) 2 , while with PbI 2 the PV performance is relatively insensitive to variations in the HTL IE between 4.8 and 5.8 eV. Our results suggest that contradictory findings in the literature on the effect of the HTL IE in perovskite photovoltaics stem partly from the different processing methods employed.

Clients are frequently recognized as perhaps having the largest impact on the eventual success or failure of treatment; however, researchers and clinicians alike often give inadequate attention to clients' perspectives on psychotherapy processes and outcomes. Researchers who do examine client variables in psychotherapy often conduct research about the client rather than from the client. The purpose of this article is to introduce a special issue focused on the client's perspective in psychotherapy. Specifically, the articles in this issue present case studies and quantitative and qualitative research that seek to (a) demonstrate how to tailor interventions according to the client's perspective and (b) identify common themes in clients' perspectives about their experiences in psychotherapy., (© 2017 Wiley Periodicals, Inc.)

The purpose of this study was to bridge the methodologies of significant events and micro-process research to gain a better understanding of clients' perceptions of helpful and hindering events in psychotherapy. A total of 16 clients were asked to review a recent psychotherapy session and, while watching, complete a moment-by-moment rating of helpful/hindrance using a dial rating system. They were also asked to describe the most helpful and hindering segments that were rated as such. The moment-by-moment ratings suggest that clients perceive a significant amount of variability within a single session. The qualitative results suggest that clients perceive both specific treatment and common factors techniques as being helpful. Further, some of the same therapist actions were rated as both helpful and hindering, but they differed in the timing and the client's experience of feeling heard and understood versus judged or given advice that was not perceived as relevant to them. These results have important implications for clinical practice., (© 2017 Wiley Periodicals, Inc.)

Cationic dendrimers are promising vectors for non-viral gene due to their well-defined size and chemistry. We have synthesized a series of succinylated fourth generation (G4) PAMAM dendrimers to control the DNA packaging in dendriplexes, allowing us to probe the role of charge on DNA packaging. The self-assembly of DNA induced by these zwitterionic PAMAM (zPAMAM) was investigated using small-angle x-ray scattering (SAXS). We demonstrate that changing the degree of modification in zPAMAM-DNA significantly alters the packing density of the resulting dendriplexes. Salt sensitivities and pH dependence on the inter-DNA spacing were also examined. The swelling and stability to salt is reduced with increasing degree of PAMAM modification. Lowering the pH leads to significantly tighter hexagonal DNA packaging. In combination, these results show zPAMAM is an effective means to modulate nucleic acid packaging in a deterministic manner.

Quantitative singlet fission has been observed for a variety of acene derivatives such as tetracene and pentacene, and efforts to extend the library of singlet fission compounds is of current interest. Preliminary calculations suggest anthradithiophenes exhibit significant exothermicity between the first optically-allowed singlet state, S 1 , and 2 × T 1 with an energy difference of >5000 cm -1 . Given the fulfillment of this ingredient for singlet fission, here we investigate the singlet fission capability of a difluorinated anthradithiophene dimer (2ADT) covalently linked by a (dimethylsilyl)ethane bridge and derivatized by triisobutylsilylethynyl (TIBS) groups. Photophysical characterization of 2ADT and the single functionalized ADT monomer were carried out in toluene and acetone solution via absorption and fluorescence spectroscopy, and their photo-initiated dynamics were investigated with time-resolved fluorescence (TRF) and transient absorption (TA) spectroscopy. In accordance with computational predictions, two conformers of 2ADT were observed via fluorescence spectroscopy and were assigned to structures with the ADT cores trans or cis to one another about the covalent bridge. The two conformers exhibited markedly different excited state deactivation mechanisms, with the minor trans population being representative of the ADT monomer showing primarily radiative decay, while the dominant cis population underwent relaxation into an excimer geometry before internally converting to the ground state. The excimer formation kinetics were found to be solvent dependent, yielding time constants of ∼1.75 ns in toluene, and ∼600 ps in acetone. While the difference in rates elicits a role for the solvent in stabilizing the excimer structure, the rate is still decidedly long compared to most singlet fission rates of analogous dimers, suggesting that the excimer is neither a kinetic nor a thermodynamic trap, yet singlet fission was still not observed. The result highlights the sensitivity of the electronic coupling element between the singlet and correlated triplet pair states, to the dimer conformation in dictating singlet fission efficiency even when the energetic requirements are met.

The substitution of sterically bulky groups at precise locations along the periphery of fused-ring aromatic systems is demonstrated to increase electrochemical oxidation potentials by preventing relaxation events in the oxidized state. Phenothiazines, which undergo significant geometric relaxation upon oxidation, are used as fused-ring models to showcase that electron-donating methyl groups, which would generally be expected to lower oxidation potential, can lead to increased oxidation potentials when used as the steric drivers. Reduction events remain inaccessible through this molecular design route, a critical characteristic for electrochemical systems where high oxidation potentials are required and in which reductive decomposition must be prevented, as in high-voltage lithium-ion batteries. This study reveals a new avenue to alter the redox characteristics of fused-ring systems that find wide use as electroactive elements across a number of developing technologies., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In order to understand how additives influence the structure and electrical properties of active layers in thin-film devices, a compositionally identical but structurally different guest-host system based on the syn and anti isomers of triethylsilylethynyl anthradithiophene (TES ADT) is systematically explored. The mobility of organic thin-film transistors (OTFTs) comprising anti TES ADT drops with the addition of only 0.01% of the syn isomer and is pinned at the mobility of OTFTs having pure syn isomer after the addition of only 10% of the isomer. As the syn isomer fraction increases, intermolecular repulsion increases, resulting in a decrease in the unit-cell density and concomitant disordering of the charge-transport pathway. This molecular disorder leads to an increase in charge trapping, causing the mobility of OTFTs to drop with increasing syn-isomer concentration. Since charge transport is sensitive to even minute fractions of molecular disorder, this work emphasizes the importance of prioritizing structural compatibility when choosing material pairs for guest-host systems., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The purpose of this meta-analysis was to examine rates of treatment refusal and premature termination for pharmacotherapy alone, psychotherapy alone, pharmacotherapy plus psychotherapy, and psychotherapy plus pill placebo treatments. A systematic review of the literature resulted in 186 comparative trials that included a report of treatment refusal and/or premature termination for at least 2 of the 4 treatment conditions. The data from these studies were pooled using a random-effects analysis. Odds Ratio effect sizes were then calculated to compare the rates between treatment conditions, once across all studies and then again for specific client disorder categories. An average treatment refusal rate of 8.2% was found across studies. Clients who were assigned to pharmacotherapy were 1.76 times more likely to refuse treatment compared with clients who were assigned psychotherapy. Differences in refusal rates for pharmacotherapy and psychotherapy were particularly evident for depressive disorders, panic disorder, and social anxiety disorder. On average, 21.9% of clients prematurely terminated their treatment. Across studies, clients who were assigned to pharmacotherapy were 1.20 times more likely to drop out compared with clients who were assigned to psychotherapy. Pharmacotherapy clients with anorexia/bulimia and depressive disorders dropped out at higher rates compared with psychotherapy clients with these disorders. Treatment refusal and dropout are significant problems in both psychotherapy and pharmacotherapy and providers of these treatments should seek to employ strategies to reduce their occurrence. (PsycINFO Database Record, ((c) 2017 APA, all rights reserved).)

A new class of nitrogen-containing arene organic semiconductors incorporating fused indolizine units is described. This system, though having a zigzag shape, mimics the electronic properties of its linear analogue pentacene as a result of nitrogen lone pair incorporation into the π-electron system. Solubilizing trialkylsilylethynyl groups were employed to target crystal packing motifs appropriate for field-effect transistor devices. The triethylsilylethynyl derivative yielded hole mobilities of 0.1 cm 2 V -1 s -1 and on/off current ratios of 10 5 .

The aim of this work is to investigate the impact of placebo response rates on the relative risk of response to drug versus placebo in randomized, double-blind, placebo-controlled clinical trials of pharmacological therapy in Bipolar Depression (BPD). Medline/PubMed publication databases were searched for randomized, double-blind, placebo-controlled trials of oral drugs used as monotherapy for the treatment of BPD. The search was limited to articles published between January 1980 and September 2015. Data extracted from 12 manuscripts and one poster with yet unpublished results, representing a total of 17 clinical trials were pooled (n = 6578). Pooled response rates for drug and placebo were 55.1% and 39.2%, corresponding to a risk ratio (RR) for responding to active treatment versus placebo of 1.29 (p < 0.001). Clinical response was defined as a 50% or greater reduction in depression scores, baseline to endpoint. A higher placebo response rate correlated with a significantly lower RR of responding to pharmacotherapy versus placebo (p = 0.002). The pooled drug and placebo response rates for studies with a placebo response rate ≤ 30% were 50.5% versus 26.6%, while corresponding values from studies with a placebo response rate >30 were 55.0% versus 41.6%. These results suggest that the relative efficacy of the active drug compared to placebo in clinical trials for BPD is highly heterogeneous across studies with different placebo response rates, with a worse performance in showing a superiority of the drug versus placebo for studies with placebo response rates >30%. It is important to maintain placebo response rates below this critical threshold, since this is one of the most challenging obstacles for new treatment development in BPD., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Two new small-molecule enzyme mimics of carbonic anhydrase were prepared and characterized. These complexes contain the salen-like ligand bis(hydroxyphenyl)phenanthroline. This ligand is similar to the salen-type ligands previously incorporated into carbonic anhydrase mimics but contains no hydrolyzable imine groups and therefore serves as a promising ligand scaffold for the synthesis of a more robust CO2 hydration catalyst. These homogeneous catalysts were investigated for CO2 hydration in concentrated primary amine solutions through which a dilute CO2 (14%) fluid stream was flowed and showed exceptional activity for increased CO2 absorption rates.

We examined efficacy and safety of one specific cranial electrical stimulator (CES) device at a fixed setting in subjects with treatment-resistant major depressive disorder (MDD). Thirty subjects (57% female, mean age 48.1 ± 12.3 years) with MDD and inadequate response to standard antidepressants were randomized to 3 weeks of treatment with CES (15/500/15,000 Hz, symmetrical rectangular biphasic current of 1-4 mAmp, 40 V) or sham CES (device off) for 20 min, 5 days per week. The primary outcome measure was improvement in the 17-item Hamilton Depression Rating Scale (HAM-D-17). Adverse effects (AEs) were assessed using the Patient Related Inventory of Side Effects (PRISE). Completion rates were 88% for CES, 100% for sham. Both treatment groups demonstrated improvement of about 3-5 points in HAM-D-17 scores (p < 0.05 for both), and no significant differences were observed between groups. Remission rates were 12% for CES, and 15% for sham, a nonsignificant difference. CES was deemed safe, with good tolerability; poor concentration and malaise were the only distressing AEs that differed significantly between CES and sham (p = 0.019 and p = 0.043, respectively). Limitations include a small sample and lack of an active comparator therapy. Although both treatment groups improved significantly, this CES at the setting chosen did not separate from sham in this sample. Thus we cannot rule out that the benefit from this setting used in this particular form of CES was due to placebo effects. Since this form of CES has other settings, future studies should test these settings and compare it against other CES devices. Clinicaltrials.gov ID: NCT01325532., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

We compare the singlet fission dynamics of five pentacene derivatives precipitated to form nanoparticles. Two nanoparticle types were distinguished by differences in their solid-state order and kinetics of triplet formation. Nanoparticles that comprise primarily weakly coupled chromophores lack the bulk structural order of the single crystal and exhibit nonexponential triplet formation kinetics (Type I), while nanoparticles that comprise primarily more strongly coupled chromophores exhibit order resembling that of the bulk crystal and triplet formation kinetics associated with the intrinsic singlet fission rates (Type II). In the highly ordered nanoparticles, singlet fission occurs most rapidly. We relate the molecular packing arrangement derived from the crystal structure of the pentacene derivatives to their singlet fission dynamics and find that slip stacking leads to rapid, subpicosecond singlet fission. We present evidence that exciton delocalization, coincident with an increased relative admixture of charge-transfer configurations in the description of the exciton wave function, facilitates rapid triplet pair formation in the case of single-step singlet fission. We extend the study to include two hexacene derivatives and find that these conclusions are generally applicable. This work highlights acene derivatives as versatile singlet fission chromophores and shows how chemical functionalization affects both solid-state order and exciton interactions and how these attributes in turn affect the rate of singlet fission.

A series of bulky end-capped [1]benzothieno[3,2-b]benzothiophenes (BTBTs) are developed in order to tune the packing structure via terminal substitution. A coupled theoretical and experimental study allows us to identify 2,7-di-tert-butylBTBT as a new high-performance organic semiconductor with large and well-balanced transfer integrals, as evidenced by quantum-chemical calculations. Single-crystal field-effect transistors show a remarkable average saturation mobility of 7.1 cm(2) V(-1) s(-1) ., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Phenothiazine and five N-substituted derivatives were evaluated as electrolyte additives for overcharge protection in LiFePO4 /synthetic graphite lithium-ion batteries. We report on the stability and reactivity of both the neutral and radical-cation forms of these six compounds. While three of the compounds show extensive overcharge protection, the remaining three last for only one to a few cycles. UV/Vis studies of redox shuttle stability in the radical cation form are consistent with the overcharge performance: redox shuttles with spectra that show little change over time exhibit extensive overcharge performance, whereas those with changing spectra have limited overcharge protection. In one case, we determined that a C-N bond cleaves upon oxidation, forming the phenothiazine radical cation and leading to premature overcharge protection failure; in another case, poor solubility appears to limit protection., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Fluorination has been demonstrated to improve stability and processing in thiophene-containing small-molecule semiconductors. Here, the impact of partial fluorination on these parameters in a pentacene derivative is examined. Although the improvement in photostability is not as dramatic, there is a clear improvement in the stability of the chromophore upon fluorination. The improvement in processability is more dramatic; devices formed by spin-coating with the fluorinated derivative perform substantially better than those formed from the nonfluorinated compound., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Background: We have previously shown an association between patient belief and treatment response in the Hypericum Depression Trial Study Group's 2002 study. We re-examined these data to determine whether clinical improvement was associated with physician belief about assigned therapy., Methods: Three hundred and forty adults with major depression and baseline scores ≥20 on the 17-item Hamilton Depression Scale (HDRS-17) were randomized to Hypericum 900-1500mg/day, sertraline 50-100mg/day, or placebo for 8 weeks. At week 8, physicians guessed their patients' treatment. We analyzed 277 subjects with at least one post-baseline visit and physician guess data. We examined association between guess and improvement in HDRS-17 and whether treatment assignment moderated the effect of belief on remission (final HDRS-17 score <8)., Results: Patient and doctor guesses agreed at 53% for sertraline, 68% for Hypericum, and 52% for placebo (kappa=0.37). Doctors guessed placebo correctly (38%) more than sertraline (18%) or Hypericum (19%) (p=0.001). Adverse event scores were significantly greater among subjects for which the clinicians guessed Hypericum (p<0.001) or sertraline (p=0.005) compared to placebo. Significant improvements in HDRS-17 score were found when comparing the Hypericum-guess (p<0.001) or the sertraline-guess group (p<0.001) against the placebo-guess group. Remission rates were significantly greater for subjects whose clinicians guessed sertraline (p<0.001) or Hypericum (p<0.001) versus placebo., Conclusion: Doctors tended to guess placebo more easily than Hypericum or sertraline, and their guesses tended to favor active therapies when improvement was more robust. Results show association but not causation, and merit more careful investigation., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Objective. We sought to demonstrate that maca root may be an effective treatment for antidepressant-induced sexual dysfunction (AISD) in women. Method. We conducted a 12-week, double-blind, placebo-controlled trial of maca root (3.0 g/day) in 45 female outpatients (mean age of 41.5 ± 12.5 years) with SSRI/SNRI-induced sexual dysfunction whose depression remitted. Endpoints were improvement in sexual functioning as per the Arizona Sexual Experience Scale (ASEX) and the Massachusetts General Hospital Sexual Function Questionnaire (MGH-SFQ). Results. 45 of 57 consented females were randomized, and 42 (30 premenopausal and 12 postmenopausal women) were eligible for a modified intent-to-treat analysis based on having had at least one postmedication visit. Remission rates by the end of treatment were higher for the maca than the placebo group, based on attainment of an ASEX total score ≤ 10 (9.5% for maca versus 4.8% for placebo), attaining an MGH-SFQ score ≤ 12 (30.0% for maca versus 20.0% for placebo) and reaching an MGH-SFQ score ≤ 8 (9.5% for maca versus 5.0% for placebo). Higher remission rates for the maca versus placebo group were associated with postmenopausal status. Maca was well tolerated. Conclusion. Maca root may alleviate SSRI-induced sexual dysfunction in postmenopausal women. This trial is registered with NCT00568126.

We report a new synthetic route to 5,11-disubstituted indeno[1,2-b]fluorene-6,12-diones that is amenable to larger scale reactions, allowing for the preparation of gram amounts of material. With this new methodology, we explored the effects on crystal packing morphology for the indeno[1,2-b]fluorene-6,12-diones by varying the substituents on the silylethynyl groups.

3,7-Disubstituted N-ethylphenothiazine derivatives were synthesized as redox shuttle candidates for lithium-ion batteries. Battery cycling results show that three derivatives prevent overcharge.

In recent years, dendriplexes, complexes of cationic dendrimers with DNA, have become attractive DNA delivery vehicles due to their well-defined chemistries. To better understand the nature of the forces condensing dendriplexes, we studied low generation poly(amidoamine) (PAMAM) dendrimer-DNA complexes and compared them to comparably charged linear arginine peptides. Using osmotic stress coupled with X-ray scattering, we have investigated the effect of molecular chain architecture on DNA-DNA intermolecular forces that determine the net attraction and equilibrium interhelical distance within these polycation condensed DNA arrays. In order to compact DNA, linear cations are believed to bind in DNA grooves and to interact with the phosphate backbone of apposing helices. We have previously shown a length dependent attraction resulting in higher packaging densities with increasing charge for linear cations. Hyperbranched polycations, such as polycationic dendrimers, presumably would not be able to bind to DNA and correlate their charges in the same manner as linear cations. We show that attractive and repulsive force amplitudes in PAMAM-DNA assemblies display significantly different trends than comparably charged linear arginines resulting in lower DNA packaging densities with increasing PAMAM generation. The salt and pH dependencies of packaging in PAMAM dendrimer-DNA and linear arginine-DNA complexes were also investigated. Significant differences in the force curve behaviour and salt and pH sensitivities suggest that different binding modes may be present in DNA condensed by dendrimers when compared to linear polycations.

Trialkylgermyl functionalization allows the development of high-performance soluble small-molecule organic semiconductors with mobilities greater than 5 cm(2) V(-1) s(-1) . Spray-deposited organic thin-film transistors show a record mobility of 2.2 cm(2) V(-1) s(-1) and demonstrate the potential for incorporation in large-area, low-cost electronic applications., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Acenes larger than pentacene are predicted to possess enticing electronic properties, but are insoluble and prone to rapid decomposition. Utilizing a combination of functionalization strategies, we present stable, solution-processable hexacenes and an evaluation of their hole and electron transport properties.

Crystals of 5-hydroxy-6-methyl-2-pyridone, (I), grown from a variety of solvents, are invariably trigonal (space group R3); these are 5-hydroxy-6-methyl-2-pyridone acetone 0.1667-solvate, C(6)H(7)NO(2)·0.1667C(3)H(6)O, (Ia), and 6-methyl-5-hydroxy-2-pyridone propan-2-ol 0.1667-solvate, C(6)H(7)NO(2)·0.1667C(3)H(8)O, (Ib), and the forms from methanol, (Ic), water, (Id), benzonitrile, (Ie), and benzyl alcohol, (If). They incorporate channels running the length of the c axis that contain extensively disordered solvent molecules. A solvent-free sublimed powder of 5-hydroxy-6-methyl-2-pyridone microcrystals is essentially isostructural. Inversion-related host molecules interact via pairs of N-H...O hydrogen bonds to form R(2)(2)(8) dimers. Six of these dimers form large R(12)(6)(42) puckered rings, in which the O atom of each N-H...O hydrogen bond is also the acceptor in an O-H...O hydrogen bond that involves the 5-hydroxy group. The large R(12)(6)(42) rings straddle the -3 axes and form stacked columns via π-π interactions between inversion-related molecules of (I) [mean interplanar spacing = 3.254 Å and ring centroid-centroid distance = 3.688 (2) Å]. The channels are lined by methyl groups, which all point inwards to the centre of the channels.

Amide functionalized anthradithiophenes (ADTs) play active acceptor roles in polymer bulk-heterojunction solar cells. The first separation of ADT isomers is reported, and the regiochemistry of the ADT has significant impact on crystal packing and solar cell performance. Cell efficiency up to 0.80%, due in large part to high open-circuit voltage (V(OC) > 1.0 V), is achieved in bulk-heterojunction solar cells comprising syn-ADT and poly(3-hexylthiophene).

The synthesis of new silylethyne-substituted hexacene derivatives to investigate their solubility, stability, and pi-stacking is reported. It was found that "butterfly" dimerization, rather than photooxidation, is the dominant decomposition pathway for these molecules and that stability can be enhanced by functionalization to prevent close contact between specific regions of the aromatic core. Dimerization regioselectivity can be altered by suitable engineering of the solid-state arrangement of the chromophores.

Phenyleneethynylene-based conjugated copolymers using benzo[1,2-d:4,5-d']bis[1,3]dioxole (BDO) in the repeating unit are reported. The electronic structure of the BDO unit imparts a localized HOMO topology while the LUMO is delocalized over the polymer backbone, so that the lowest optical absorption band of the polymer has considerable intramolecular charge transfer character. This contrasts with published donor-acceptor polymers with localized LUMO and delocalized HOMO. The very large Stokes shifts of the monomers, which are due to the small oscillator strength of the lowest optical transition, are largely retained in the polymers as a result of covalently constrained dihedral angles in the substituents (not the backbone), as predicted/explained by calculations.