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Because acrylonitrile‐phenylene‐based π‐conjugated molecules have highly rigid structures (or low structural flexibility), these molecules have low solubility in various organic solvents, including nonpolar and polar solvents such as hexane, ethanol, and dimethyl sulfoxide. Alkylation or PEGulation strategies are useful approaches for designing highly soluble acrylonitrile‐phenylene compounds, but the number of good solvents is limited. Herein, we report mesityl‐appended 1,4‐bis(β‐acrylonitrile)‐2,5‐dimethoxybenzene including an electron donor–acceptor system. The molecule shows good solubility in various organic solvents, such as hexane, toluene, chloroform, dichloromethane, acetone, ethanol, N,N‐dimethylformamide, acetonitrile, and dimethyl sulfoxide, owing to the appended bulky mesityl groups. Spectroscopic measurements were performed in various solutions. The solvatochromic behaviour was investigated according to the polarity and affinities by absorption and photoluminescence (PL) spectroscopic analyses in various solvents. The acrylonitrile unit in the π‐conjugated structure allows rotation under ambient light. E−Z isomerisation was observed owing to its structural flexibility. This feature gave two fluorescent molecular crystals: blue‐PL Z,Z‐molecular crystal BC (minor material, CCDC 2108373, λem=473 nm) and green‐PL E,E‐molecular crystal GC (major material, CCDC 2108365, λem=508 nm). It is reasonable that the more planar donor–acceptor core structure of the E,E‐crystal shows lower energy fluorescence than the slightly twisted structure of the Z,Z‐crystal. [ABSTRACT FROM AUTHOR]

Stimuli‐triggered crystal‐to‐crystal and single‐crystal‐to‐single‐crystal (SCSC) transformations have received significant attention in the scientific community. To visualize such phenomenon, controlling the optical properties and the thermodynamic stability of the molecular crystals is a very important research subject. In this report, the selective growth of photoluminescent (PL) 1,8‐bisphenylanthracene polymorphic (cI and cII) and 1,2‐dichloroethane‐inclusion crystals (iC) under various optimized conditions is described. These crystals exhibited unique mechano‐ and thermoresponsive disordering, crystal‐to‐crystal phase transition, and SCSC phase transition. In particular, rapid thermostimulus SCSC occurred from blue‐PL cI into greenish‐blue‐PL cII. Interestingly, the SCSC phase transition of cI into cII was triggered by thermal stimuli and propagated spontaneously. Thermotriggered domino‐like SCSC phase transition was observed on a fully visible timescale (ca. 125 μm min−1). [ABSTRACT FROM AUTHOR]

Mechanical deformation-induced physical property changes of flexible molecular crystals are unique topics in materials chemistry. Here, the mechanically curving-induced photoluminescence (PL) and PL anisotropy changes in an elastic organic crystal were successfully investigated by spatially resolved μ-PL spectroscopy for the PL analysis at both the outer and inner sides. The PL characters derived from intermolecular π–π stacking and transition dipole orientations changes with respect to the elongation of the outer side of the crystals. The results suggested that the molecular packing and its directional arrangement change with the crystal deformation. [ABSTRACT FROM AUTHOR]

Whispering‐gallery‐mode (WGM) resonators composed of organic and/or inorganic materials have been used in highly sensitive sensors, logic gates, and miniaturized lasers because of the total internal reflection of photons. However, most fabrication methods have been limited to bottom‐up self‐assembly; whereas, a facile top‐down process is preferable. Here, a wet‐process fabrication of WGM resonators mixed with 5 µm‐diameter spherical silica‐gels and various π‐conjugated compounds is demonstrated. The materials are fabricated by dip‐coating photoluminescent molecules onto submicron‐scale silica‐gel spheres. The shapes and large specific surface areas of templates are maintained before and after coating, and the coated molecules are uniformly distributed. The hybrid spheres provided WGM photoluminescence spectra based on the total internal reflection of photoluminescence in the sphere. The hybrid spheres are applicable as WGM sensors because of their large specific surface area (>4 × 102 m2 g−1). In particular, gas sensing of toluene, which has been used as a standard for environmental contamination, and found that the WGM photoluminescence peaks are shifted by 5 nm is demonstrated. The detection resolution is calculated to be several hundred ppm level. The hybrid spheres can be placed or transferred onto various surfaces without micromanipulation, which suggested a wide range of possible applications. [ABSTRACT FROM AUTHOR]

Elastic organic crystals have attracted considerable attention as next‐generation flexible smart materials. However, the detailed information on both molecular packing change and macroscopic mechanical crystal deformations upon applied stress is still insufficient. Herein, we report that fluorescent single crystals of 9,10‐dibromoanthracene are elastically bendable and stretchable, which allows a detailed investigation of the deformation behavior. We clearly observed a Poisson effect for the crystal, where the short axes (b and c‐axes) of the crystal are contracted upon elongation along the long axis (a‐axis). Moreover, we found that the Poisson's ratios along the b‐axis and c‐axis are largely different. Theoretical molecular simulation suggests that the tilting motion of the anthracene may be responsible for the large deformation along the c‐axis. Spatially resolved photoluminescence (PL) measurement of the bent elastic crystals reveals that the PL spectra at the outer (elongated), central (neutral), and inner (contracted) sides are different from each other. [ABSTRACT FROM AUTHOR]

Elastic organic crystals have attracted considerable attention as next‐generation flexible smart materials. However, the detailed information on both molecular packing change and macroscopic mechanical crystal deformations upon applied stress is still insufficient. Herein, we report that fluorescent single crystals of 9,10‐dibromoanthracene are elastically bendable and stretchable, which allows a detailed investigation of the deformation behavior. We clearly observed a Poisson effect for the crystal, where the short axes (b and c‐axes) of the crystal are contracted upon elongation along the long axis (a‐axis). Moreover, we found that the Poisson's ratios along the b‐axis and c‐axis are largely different. Theoretical molecular simulation suggests that the tilting motion of the anthracene may be responsible for the large deformation along the c‐axis. Spatially resolved photoluminescence (PL) measurement of the bent elastic crystals reveals that the PL spectra at the outer (elongated), central (neutral), and inner (contracted) sides are different from each other. [ABSTRACT FROM AUTHOR]

Here we have studied the directional nature of the fluorescence emission of a centimetre-scale organic crystal. Sky blue-colored fluorescence (λPL = 481 nm) of the (010) face and the green-colored fluorescence (λPL = 502 nm) of the (001) face were observed, because the (010) and (001) faces of the crystal have different directional orientations of the molecules. Interestingly, the mechanically induced shaping of the centimetre-scaled single crystal caused a new green-colored fluorescent (001) face to appear in the cross section. [ABSTRACT FROM AUTHOR]

To identify the simplest organic structure for an emitter, we focused on 2,5‐dimethoxybenzene‐1,4‐dicarboaldehyde. This symmetric molecule has a very low molecular weight (MW=194), a single benzene unit, and consists of only three elements (H, C and O). It forms highly efficient and pure emitting crystals (λem=499 nm, ΦF=0.42, FWHM=42 nm) due to the rigid structure based on the single benzene framework and four intramolecular hydrogen bonds between electron‐donating methoxy and electron‐accepting aldehyde groups. This crystal acts as a good optical waveguide with pure green emission (FWHM=34 nm) and very low loss coefficient (0.00120 dB/μm). A simple molecule, 2,5‐dimethoxybenzene‐1,4‐dicarboaldehyde, is symmetric, has a low molecular weight (MW=194) and contains a single benzene unit. Highly efficient emitting crystals were obtained from this molecule, and this efficiency is ascribed to the rigid structure. These crystals may serve as a good fluorescent waveguide with green fluorescence and a low loss coefficient. [ABSTRACT FROM AUTHOR]

Abstract Here we report the facile derivatization of a cyano-substituted stilbene into higher π-extended analogues. The cyano-substituted stilbene, which serves as a synthetic scaffold, has a bromo group and a formyl group on its 4- and 4′-position of the phenylene rings and thus readily undergoes selective transformation into other functional groups using various simple organic reactions. The resultant π-conjugated molecules that contain a cyano-substituted stilbene skeleton exhibit fluorescence in solution and in the solid state. Graphical abstract Image 1 Highlights • Cyano-substituted stilbene was used as a synthetic scaffold. • Various π-extended analogues were obtained in good yields. • The resultant π-conjugated molecules show fluorescence. [ABSTRACT FROM AUTHOR]

To create low band‐gap, fluorescent, and elastic organic crystal emitters, we focused on an extended π‐conjugated system based on: a) a planar conformation,b) a rigid structure, and c) controlled intermolecular interactions. Herein, we report on two fluorescent and highly flexible organic crystals (1 and 2) which could bend under an applied stress. The bent crystals rapidly recover their straight shape upon release of the stress. Crystal 1 with a tetrafluoropyridyl terminal unit and a lower band‐gap energy (orange emission, λem=573 nm, ΦF=0.50), showed no bending mechanofluorochromism and had superior performance as an optical waveguide with reddish orange emission. The waveguide performance of the crystal did not decrease under bending stress. For crystal 2 with a pentafluorophenyl terminal unit (green emission, λem=500 nm, ΦF=0.38), the original waveguide performance decreased under an applied bending stress; however, this crystal showed a unique bending mechanofluorochromism. [ABSTRACT FROM AUTHOR]

To create low band‐gap, fluorescent, and elastic organic crystal emitters, we focused on an extended π‐conjugated system based on: a) a planar conformation,b) a rigid structure, and c) controlled intermolecular interactions. Herein, we report on two fluorescent and highly flexible organic crystals (1 and 2) which could bend under an applied stress. The bent crystals rapidly recover their straight shape upon release of the stress. Crystal 1 with a tetrafluoropyridyl terminal unit and a lower band‐gap energy (orange emission, λem=573 nm, ΦF=0.50), showed no bending mechanofluorochromism and had superior performance as an optical waveguide with reddish orange emission. The waveguide performance of the crystal did not decrease under bending stress. For crystal 2 with a pentafluorophenyl terminal unit (green emission, λem=500 nm, ΦF=0.38), the original waveguide performance decreased under an applied bending stress; however, this crystal showed a unique bending mechanofluorochromism. Two elastic and fluorescent organic single crystals were successfully created based on an original molecular design. The crystals showed bending mechanofluorochromism and high performance as a flexible waveguide. [ABSTRACT FROM AUTHOR]

Abstract: In π‐conjugated polymers (πCPs), crystallinity and fluorescence typically exhibit a trade‐off relationship. Here, we have synthesized a highly crystalline and fluorescent π‐conjugated polymer with a simple alternating structure of 1,2,4,5‐tetrafluorophenylene and 3,3′‐dihexyl‐2,2′‐bithiophene units. In film, the polymer exhibited efficient red‐colored fluorescence, an improved quantum yield (Φsol=13 %→Φfilm=23 %) and a crystalline structure. Interestingly, supramolecular gel formation occurred in appropriate solvents, and the macrostructure and fluorescence properties of the gel could be directly controlled by the choice of the solvent. The polymer self‐assembled into a spherical form that exhibited red fluorescence in non‐aromatic solvent (1,2‐dichloroethane) and into a fibrous form that exhibited yellow fluorescence in aromatic solvent (mesitylene). [ABSTRACT FROM AUTHOR]

Abstract: Mechanically induced shaping (i.e., top‐down processing) of organic single crystals is an undeveloped area of research because applying stress to such nonflexible crystalline materials generally causes them to disintegrate. Herein, we present a mechanically induced splitting phenomenon of elastic organic single crystals, and study on a facile shaping processing method of centimeter‐scale elastic organic single crystal of fluorescent π‐conjugated molecule into various fine crystal fibers (thickness: ≈50 μm; width: ≈150 μm; length: ≈25 mm). The fibers produced maintained their original crystal structure and properties (i.e., fluorescence efficiency and elastic flexibility). [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, we report the synthesis of π-conjugated network polymers including unique fluorescent units via palladium-catalyzed direct (CH) arylation polycondensation of 1,2,4,5-tetrafluorobenzene with tetrabromoarenes. The obtained polymers, including tetraphenylethene (TPE) or pyrene (PYR) units, had microporous structures with the specific Brunauer-Emmett-Teller (BET) surface areas at 508 and 824 m2 g−1, respectively. These polymers possessed narrow pore distributions (<15 nm). These analyses supported that π-conjugated microporous polymers (CMPs) were synthesized by the direct arylation. Similar to the result of BET surface areas, carbon capture capacity of CMP based on PYR unit was higher than that of CMP based on TPE unit. Because the nitrogen capture capacity of these CMPs was low (≈ 0), selectivity of carbon dioxide adsorption was very high. TPE is a typical aggregation-induced emission unit but PYR is an aggregation-caused quenching (ACQ) molecule. The incorporation of TPE unit into the microporous polymer gave green-colored fluorescence (Φ = 0.12). The polymer including PYR units also showed the green-colored fluorescence (Φ = 0.05) even though the ACQ property. These synthesized CMPs exhibited characteristic solvatofluorochromism. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 3862-3867 [ABSTRACT FROM AUTHOR]

An efficient cross-coupling reaction using a low cost carbon-supported palladium (Pd/C) catalyst for the synthesis of cross-conjugated compounds, diaryl[n]dendralenes, has been developed. The reaction of a propargylic biscarbonate with phenylboronic acid using Pd/C and phosphine ligand (S-Phos) gave 2,3-diphenyl[2]dendralene in high yield. We found that Pd/C was an effective catalyst for the synthesis of dialyl[n]dendralenes. The synthesis of various dendralenes was successfully achieved under the optimized conditions, giving dialyl [2] and [4] dendralenes in good yields. [ABSTRACT FROM AUTHOR]

We have demonstrated a direct arylation polycondensation of 3,4-ethylenedioxythiophene with 2,7-dibromo-9,9-dioctylfluorene using palladium on carbon (Pd/C) as a catalyst. Pd/C is a low-cost solid-supported palladium catalyst, giving one of the effective catalytic systems for direct arylation. The Pd/C-catalyzed direct arylation polycondensation with acetic acid/potassium carbonate in N,N-dimethylacetamide furnished a high molecular weight p-conjugated alternating copolymer of EDOT-fluorene (Mn589,300, Mw/Mn = 3.27) in high yield. The polycondensation of EDOT with various dibromoarenes was also achieved, giving EDOT-carbazole, EDOT-dialylamine, and EDOT-bithiophene polymers. Optical and electrochemical properties of the polymers were also discussed. [ABSTRACT FROM AUTHOR]

We have demonstrated a direct arylation polycondensation of β-unprotected chalcogen heteroles (furan, thiophene and selenophene) under phosphine-free conditions. The polycondensation of furan and thiophene using a solid-supported palladium catalyst, Pd/C, gave alternating copolymers ( M n = 8000–10000), but the polycondensation of these monomers using common palladium catalysts such as Pd(OAc) 2 gave insoluble polymeric products resulting from β-defects and network formation. Selenophene was a less reactive monomer for direct arylation using these catalysts, Pd/C and Pd(OAc) 2 , yielding low molecular weight copolymer ( M n < 2500). On the other hand, PdCl 2 was the most effective catalyst for the polycondensation of selenophene. The high molecular weight polymer ( M n = 11800) could be obtained. The 1 H NMR and UV-vis absorption spectra of the polymers obtained from furan, thiophene and selenophene were similar to those of the polymers synthesized by Suzuki-Miyaura cross-coupling polycondensation. [ABSTRACT FROM AUTHOR]

Objective: To clarify the incidence, clinical background and surgical characteristics of chronic adnexal torsion in comparison to acute adnexal torsion.Study Design: The patients were divided into three categories based on the period from the onset of symptoms to surgical management: acute (≤24h), subacute (2days) and chronic adnexal torsions (≥3days). Cases, in which the onset of symptoms was unspecified, were included in the chronic adnexal torsion group. Then, a retrospective comparative study of acute (49 patients) and chronic adnexal torsion (45 patients) was performed. Laparoscopic surgery was performed as a primary surgical procedure.Results: In chronic adnexal torsion, surgery was performed at a median of 9days (range: 3-270days) after the onset of symptoms. The apparent onset of symptoms was not noted in 2 cases. All cases with acute adnexal torsion received emergency surgery. In contrast, emergency surgery was performed only in 13 patients with chronic adnexal torsion. Patients with chronic adnexal torsion were significantly older than those with acute adnexal torsion. Isolated tubal torsion was more frequent in chronic adnexal torsion. With the exception of 2 cases with chronic adnexal torsion in which laparotomic conversion was required due to severe adhesion, and 2 cases with acute adnexal torsion with advanced gestational age, who were managed by initial laparotomy, laparoscopic surgery was successful. Unilateral salpingo-oophorectomy was the most frequent surgical procedure in both groups. When confined to the patients who expressed a wish for adnexal preservation, adnexal cystectomy or detorsion was possible in 60.9% of the acute torsion cases and 57.1% of the chronic adnexal torsion cases. Severe necrosis of the adnexal tissue and extensive pelvic adhesion were the more frequent associated conditions in chronic adnexal torsion. Among the patients who were successfully managed by laparoscopic surgery, the duration of surgery was significantly longer in the patients with chronic adnexal torsion. Severe necrosis that makes a pathological diagnosis difficult was the most frequent finding in cases of chronic adnexal torsion.Conclusion: Chronic adnexal torsion still represents a diagnostic and therapeutic challenge that should be recognized as a distinct and more frequently encountered disease entity. [ABSTRACT FROM AUTHOR]

A palladium catalyst immobilized on thiol-modified silica gel (PITS) was developed for the efficient synthesis of various π-conjugated oligomers and polymers. Direct arylation of 3,4-ethylenedioxythiophene (EDOT) gave not only the corresponding oligomeric compounds in high yields but also high-molecular-weight π-conjugated polymers in high yields. Moreover, the polycondensation of the β-unprotected bithiophene monomer with dibromoarenes was also achieved. This solid-supported Pd catalyst was used to conduct regioselective direct arylation polycondensation, giving high-molecular-weight π-conjugated polymers in high purity (low levels of residual Pd impurities and structural β-defects). [ABSTRACT FROM AUTHOR]

Objective: To evaluate the safety and feasibility of gasless transumbilical single-port laparoscopic-assisted vaginal hysterectomy (LAVH) for the management of large uteri weighing 500g or more.Study Design: We conducted a retrospective comparative study of women with large uteri, each undergoing gasless multi-port or single-port LAVH. Preoperatively, gonadotropin-releasing hormone agonist was administered and autologous blood was donated except for cases requiring immediate surgery. Additionally, intraoperative blood salvage and donation was performed in select cases. In single-port LAVH, a wound retractor was used to make a working port through umbilical incision. After the surgical view was secured using an abdominal wall-lift device, the surgical procedures were performed using conventional laparoscopic instruments. In select cases, temporary endovascular occlusion of the bilateral internal iliac arteries was performed to reduce intraoperative hemorrhaging.Results: Of the 650 women managed by multi-port or single-port LAVH, 55 and 67 women each with uteri weighing 500g or more, respectively, were included. In single-port LAVH group, the median age was 47 years. Twelve women were nulliparous and 3 women with 2 cesarean deliveries each, had never had a vaginal delivery. The most frequent surgical indication was uterine myoma. In the single-port LAVH group, the surgical procedures included LAVH alone (n=36), LAVH and bilateral salpingo-oophorectomy (n=22), LAVH and unilateral salpingo-oophorectomy (n=8), and LAVH and appendectomy (n=1). Extensive adhesiolysis was required in eight cases. The median extirpated tissue weight was 652g with a median estimated intraoperative blood loss of 450mL. A significant positive linear correlation was observed between the operative time or estimated blood loss and the extirpated uterine weigh. Although excessive bleeding exceeding 1000mL was noted in 15 cases, a transfusion of bank blood was not required by using preoperatively donated autologous blood and intraoperative autologous blood salvage and donation. Extended hospitalization was required in six cases. The median surgical duration in the single-port LAVH group was significantly longer than that in the multi-port LAVH group.Conclusion: Gasless single-port LAVH is a feasible alternative that can yield similar major surgical outcomes as multi-port LAVH, with potential cosmetic benefit. [ABSTRACT FROM AUTHOR]

We have successfully synthesized π-conjugated microporous polymers (CMPs) via direct arylation of fluoroarenes with 2,4,6-tris(4-bromophenyl)-1,3,5-triazine. Both 1,2,4,5-tetrafluorobenzene and 1,3,5-trifluorobenzene were good monomers to give the networks, CMP1 and CMP2 , respectively. Characterization of the insoluble materials was successfully achieved by high performance solid-state 13 C and 19 F CP/MAS NMR spectroscopy. The signals appeared in the aromatic region. No end group signals were observed in the 13 C NMR spectrum of CMP1 , but CMP2 showed the unreacted C–H signal of the trifluorobenzene unit. CMP2 showed higher Brunauer–Emmett–Teller (BET) surface area than CMP1 . The number of branch controlled (or tailored) the porosity of the polymer networks. The polymers have microporocity with CO 2 capture capacity. The CO 2 capture capacity of CMP2 (16.75 cm 3 g -1 ) was higher than that of CMP1 (11.49 cm 3 g -1 ) at 1.0 bar. [ABSTRACT FROM AUTHOR]

An elastic organic crystal of a π-conjugated molecule has been fabricated. A large fluorescent single crystal of 1,4-bis[2-(4-methylthienyl)]-2,3,5,6-tetrafluorobenzene (over 1 cm long) exhibited a fibril lamella morphology based on slip-stacked molecular wires, and it was found to be a remarkably elastic crystalline material. The straight crystal was capable of bending more than 180° under applied stress and then quickly reverted to its original shape upon relaxation. In addition, the fluorescence quantum yield of the crystal was about twice that of the compound in THF solution. Mechanical bending-relaxation resulted in reversible change of the morphology and fluorescence. This research offers a more general approach to flexible crystals as a promising new family of organic semiconducting materials. [ABSTRACT FROM AUTHOR]

An elastic organic crystal of a π-conjugated molecule has been fabricated. A large fluorescent single crystal of 1,4-bis[2-(4-methylthienyl)]-2,3,5,6-tetrafluorobenzene (over 1 cm long) exhibited a fibril lamella morphology based on slip-stacked molecular wires, and it was found to be a remarkably elastic crystalline material. The straight crystal was capable of bending more than 180° under applied stress and then quickly reverted to its original shape upon relaxation. In addition, the fluorescence quantum yield of the crystal was about twice that of the compound in THF solution. Mechanical bending-relaxation resulted in reversible change of the morphology and fluorescence. This research offers a more general approach to flexible crystals as a promising new family of organic semiconducting materials. [ABSTRACT FROM AUTHOR]

To realize organic integrated optoelectronic circuits, there is a need for anisotropic optical waveguides at the micro/nanoscale. Anisotropic alignment of one‐dimensional‐ordered supramolecular structures composed of light‐emissive π‐conjugated molecules in a crystal may meet the requirements of such waveguides. Here, a bipyridyl‐appended acrylonitrile‐based π‐conjugated molecule was designed, which produced a one‐dimensional supramolecular polymer constructed through non‐covalent bonding between a lone pair in bipyridyl and a σ‐hole in 1,4‐diiodo‐2,3,5,6‐tetrafluorobenzene. The one‐dimensional copolymer of bipyridyl and 1,4‐diiodo‐2,3,5,6‐tetrafluorobenzene is aligned horizontally with the two‐dimensional crystal surface because of the angle‐controlled supramolecular synthons. As a result of control over the non‐covalent bonding direction, anisotropic photoluminescence and photon transport (optical waveguiding) characteristics are realized by orienting the transition dipole moment horizontally with respect to the two‐dimensional surface. Compared with the loss coefficient αL=52 dB cm−1 for the long‐axis direction of the two‐dimensional platelet cocrystal, a very large difference of αS=2111 dB cm−1 is present in the crystal short‐axis direction. The anisotropic waveguiding ability, αL/αS, is estimated to be 41, which is more than an order of magnitude greater than previously reported two‐dimensional platelet crystal waveguides. This supramolecular synthon provides an approach to designing anisotropic photon transporters and highly regulated optical logic circuits. [ABSTRACT FROM AUTHOR]

Keywords: Acrylonitrile; -Conjugated Molecules; Solvatochlomism; Crystal Enginnering; Fluorescence EN Acrylonitrile -Conjugated Molecules Solvatochlomism Crystal Enginnering Fluorescence 1 1 1 09/30/22 20220927 NES 220927 The cover picture shows "Niyodo Liver (in Kochi)" and structures of fluorescent molecules. Cover Picture: Mesityl-Appended 1,4-Bis( -acrylonitrile)-2,5-dimethoxybenzene: Blue and Green Fluorescent Crystals from a Soluble Donor-Acceptor Molecular System (ChemistrySelect 36/2022) Acrylonitrile, Fluorescence, -Conjugated Molecules, Solvatochlomism, Crystal Enginnering. [Extracted from the article]

Molecular crystals of Pt(II) complexes with metallophilic interactions can provide bright assembly-induced luminescence with colour tunability. However, the brittleness of many of these crystals makes their application in flexible optical materials difficult. Herein, we have achieved the elastic deformation of crystals of polyhalogenated Pt(II) complexes exhibiting bright assembly-induced luminescence. A crystal of [Pt(bpic)(dFppy)] (Hbpic = 5-bromopicolinic acid, HdFppy = 2-(2,4-difluorophenyl)pyridine) and a co-crystal of [Pt(bpic)(dFppy)] and [Pt(bpic)(ppy)] (Hppy = 2-phenylpyridine) were found to exhibit significant elastic deformation due to their highly anisotropic interaction topologies. While the crystal of [Pt(bpic)(dFppy)] exhibited monomer-based ligand-centred 3ππ* emission with an emission quantum yield of 0.40, the co-crystal exhibited bright, triplet metal–metal-to-ligand charge transfer (3MMLCT) emission owing to Pt⋯Pt interactions, thereby achieving a significantly higher emission quantum yield of 0.94. [ABSTRACT FROM AUTHOR]

Molecular crystals exhibiting optical waveguiding are strongly dependent on total internal reflection, molecular stacking arrangements, spatial distributions of transition dipole moments, and topologies. Fluoranthene derivatives are popular fluorescent dyes that have not yet been engineered into crystalline optical materials. Here, a naphthyl‐appended naphtho[k]fluoranthene that exhibits efficient fluorescence in solution and in the solid state is newly synthesized through a one‐pot Pd‐catalyzed reaction of 1,8‐dibromonapthalene. It selectively gives two crystal topologies derived from direction‐specific crystal growth. Using spatially resolved photoluminescence analyses, the direction‐oriented light that propagates along these topologies (each face of the crystal) is investigated. There are different optical‐loss coefficients along the various directions on each face. Therefore, face‐specific waveguiding depends on molecular arrangements. Anisotropic waveguiding in each face is observed. Overall, these results suggest potential applications of fluoranthene crystals and their topological 2D planes as optical waveguides and integrated optical circuits. [ABSTRACT FROM AUTHOR]

Fluorescence and solubility switching of a pyridine ‐ fluorene alternating copolymer film via Lewis acid (BF3 ‐ OEt2) ‐ base (Et3N) vapor treatments is reported. The solubility switching of the polymer film via the Lewis acid ‐ base vapor treatment method could be applied to pattern development. [ABSTRACT FROM AUTHOR]

Aim To report our experience with pregnancy outcomes after emergent laparoscopic surgery for acute adnexal disorders at less than 10 weeks of gestation when surgical intervention could be more invasive to intrauterine pregnancy. Methods Gasless multiport laparoscopic surgery or transumbilical laparoendoscopic single-site surgery was performed with securing of the surgical view by the abdominal wall-lift method. Intraoperative autologous blood salvage and donation was performed in cases associated with significant hemoperitoneum. Results Six cases of ovarian bleeding with ruptured corpus luteal cyst, three cases of adnexal torsion with corpus luteal cyst, and one case each of ruptured heterotopic ampullary pregnancy and heterotopic tubal stump isthmic pregnancy after salpingectomy were managed. For ruptured corpus luteal cyst, hemostasis was achieved by removal of hematoma followed by suturing. For adnexal torsion, detorsion with cyst aspiration was performed in two cases and detorsion alone was performed in one case. For ruptured heterotopic ampullary pregnancy, unilateral salpingectomy was performed. For ruptured heterotopic tubal stump isthmic pregnancy after salpingectomy, removal of the expelled villous tissue followed by hemostatic coagulation was performed. In five cases associated with massive hemoperitoneum, intraoperative autologous blood salvage and donation were performed to avoid homologous blood transfusion. After surgery, seven live births were achieved, while two cases of biochemical pregnancy loss and a case of complete miscarriage were noted. Conclusion Although miscarriage could be a significant concern in the perioperative period, gasless laparoscopic surgery appeared to be feasible for management of acute adnexal disorders at less than 10 weeks of gestation. [ABSTRACT FROM AUTHOR]

Abstract: Poly(3,5-dinitro-9-fluorenone-alt-9,9-dioctylfluorene) was synthesized from 2,7-dibromo-3,5-dinitro-9-fluorenone. This polymer shows high electron-accepting property compared with its non-substituted counter part, poly(9-fluorenone-alt-9,9-dioctylfluorene). This polymer also exhibits interesting absorption behavior based on the existence of high-energy intramolecular charge transfer interaction between new electron-accepting and common donating moieties and “keto-defects” character. [Copyright &y& Elsevier]

Abstract: Selective anodic chlorination of a poly(3-hexylthiophene) was successfully carried out by electrochemical polymer reaction. NMR and EDX analyses revealed the selective and sufficient substitution of chlorine atom at the 4-position of the repeating thiophene ring. GPC measurement of the polymer before and after electrolysis indicated that neither decomposition nor propagation of the polymer occurred even after passage of the excess charge. The optical and electrochemical properties of the obtained chlorinated polymer were investigated in detail. [Copyright &y& Elsevier]

Cover Feature: Thermotriggered Domino-like Single-Crystal-to-Single-Crystal Phase Transition from Face-to-Edge to Face-to-Face Packing of Anthracenes (Chem. Eur. J. 70/2021) Keywords: crystallization; photoluminescence; polymorphism; single-crystals; phase transition EN crystallization photoluminescence polymorphism single-crystals phase transition 17507 17507 1 12/22/21 20211215 NES 211215 B The thermotriggered domino-like b single-crystal-to-single-crystal phase transition from the blue-photoluminescent face-to-edge packed 1,8-bisphenylanthracene crystal to the face-to-face molecular packed greenish-blue-photoluminescent crystal was successfully observed on a fully visible timescale. Crystallization, photoluminescence, polymorphism, single-crystals, phase transition. [Extracted from the article]

Anthracene (C14H10) and its derivatives, π‐conjugated molecules in acenes, have been widely researched in terms of their reactions, physical properties, and self‐assembly (or crystal engineering). These molecules can be functionalized to tune reactivities, optoelectronic properties, and self‐assembling abilities. Structural changes in the molecular assemblies, solid states, and crystals have recently been discovered. Therefore, a systematic discussion of anthracene's molecular structure, packing, and optical properties based on its intermolecular structure and phase transitions is important for future chemical and structural design. In the present review, we discuss anthracene's molecular design, dimer packing, and crystal structure, focusing on the structural phase transitions of its crystals. We also provide examples of the phase transitions of anthracene crystals. Changes to edge‐to‐face of CH‐π interaction and face‐to‐face packing of π‐π interaction affect the thermodynamic stabilities of various crystal structures. These structures can inform the prediction of structural and physical properties. [ABSTRACT FROM AUTHOR]

It is generally believed that organic single crystals composed of a densely packed arrangement of anisotropic, organic small molecules are less useful as functional materials due to their mechanically inflexible and brittle nature, compared to polymers bearing flexible chains and thereby exhibiting viscoelasticity. Nevertheless, organic crystals have attracted much attention because of their tunable optoelectronic properties and a variety of elegant crystal habits and unique ordered or disordered molecular packings arising from the anisotropic molecular structures. However, the recent emergence of flexible organic crystal materials showing plasticity and elasticity has considerably changed the concept of organic single crystals. In this review, the author summarizes the state-of-the-art development of flexible organic crystal materials, especially functional elastic organic crystals which are expected to provide a foothold for the next generation of organic crystal materials. [ABSTRACT FROM AUTHOR]

Anodic fluorodesulfurization of a poly(fluorene) derivative coated on a Pt electrode was successfully carried out in an ionic liquid hydrogen fluoride salt, yielding a alternating copolymer containing a difluorofluorene moiety. [ABSTRACT FROM AUTHOR]

The cover feature shows how a simple molecule, 2,5‐dimethoxybenzene‐1,4‐dicarboxaldehyde, which is symmetric, has a low molecular weight (MW=194) and comprises a single benzene unit and only three constitutent elements (H, C and O), forms highly efficient emitting crystals. These crystals act as a good fluorescent waveguide with green fluorescence and low loss coefficient. Details are given in the Communication by S. Hayashi et al. on page 247 in Issue 3, 2019 (DOI: 10.1002/cplu.201800597). [ABSTRACT FROM AUTHOR]

Funktionelle organische Kristalle mit elastischer Flexibilität bieten sich für Anwendungen in leistungsstarken Fluoreszenzwellenleitern und reversiblen Mechanofluorosensoren an. In ihrer Zuschrift auf S. 17248 ff. zeigen S. Hayashi, K. Takagi et al., dass eine geringfügige Modifikation der Endgruppe zu drastisch veränderten optischen Funktionen führen kann. [ABSTRACT FROM AUTHOR]

Functional organic crystals with elastic flexibility can be applied in high‐performance fluorescent waveguides and reversible mechanofluorosensors. In their Communication on page 17002 ff., S. Hayashi, K. Takagi et al. show that a slight modification of the terminal group results in a dramatic change of the optical functions. [ABSTRACT FROM AUTHOR]

• We found Z-E-isomerization of anthracene-acrylonitrile-phenyl system. • Crystal growth under ambient light gives two crystals Z-/E-isomers which ratio reached 2:1. • The crystals show unique properties as AIE (aggregation-induced emission) luminogen, AIEgen. Acrylonitrile-based π-conjugated molecules are an important class of molecular materials due to their unique solid-state optical properties. On the other hand, anthracenes are also known as classical structures demonstrated unique reactivities and optical properties. Herein, we report crystal structure and optical properties of 9-(4-methoxyphenylacrylonitrile)anthracene, AA. Knoevenagel condensation synthesis yielded Z -AA. Interestingly, we found that Z-E-isomerization was observed under ambient light. Thus, Z -AA and E -AA crystals were obtained by crystallization under ambient light. The ratio of Z-/E-isomers is reached to 2:1 because of higher thermodynamic stability of Z -AA. The twisted molecular system of anthracene-acrylonitrile-phenyl system in Z -AA and E -AA gave intramolecular charge transfer interaction between electron donor-acceptor system. While both isomers showed no fluorescence in dichloromethane, both crystals exhibited fluorescence ( Z -AA crystal: λ = 541 nm, Φ = 0.04, E -AA crystal: λ = 531 nm, Φ = 0.02), indicating that the molecule behaves as an AIE (aggregation-induced emission) luminogen, AIEgen. [ABSTRACT FROM AUTHOR]

Herein, we report our experimental and computational investigations on a stable and modifiable As-bridged dipyridinoheterole, dipyridinoarsole. Oxidation of the arsenic atom changes the frontier orbital energies and quaternization of nitrogen atoms produces electrochromic materials. Dipyridinoarsole is suitable for practical applications due to its superior stability compared to its phosphole analogues. [ABSTRACT FROM AUTHOR]

Keywords: anisotropy; fluoranthene; molecular crystals; optical waveguides EN anisotropy fluoranthene molecular crystals optical waveguides 1 1 1 07/05/23 20230701 NES 230701 In article number 2201810, Shotaro Hayashi and colleagues synthesize a naphtho[k]fluoranthene that exhibits efficient fluorescence in solution and in the solid state is successfully established. Unique 2D Face Topologies in Naphthyl-Appended Naphtho[k]fluoranthene-Based 3D Crystals for Optical Waveguide (Advanced Optical Materials 13/2023) Anisotropy, fluoranthene, molecular crystals, optical waveguides. [Extracted from the article]

Background Gynandroblastoma is an extremely rare ovarian sex cord tumor with malignant potential. Case An 18-year-old adolescent experienced intermittent vaginal bleeding. A year later, a right adnexal mass with a heterogeneous imaging appearance was identified. Laparoendoscopic single-site ovarian tumorectomy was performed. A histopathological examination showed gynandroblastoma composed of juvenile granulosa and Sertoli-Leydig cells. Because the tumor was upstaged to stage Ic because of cyst rupture during surgery, three cycles of adjuvant chemotherapy with carboplatin and paclitaxel were added. Three years after surgery, no signs of recurrence have been noted. Summary and Conclusion The present findings can help clinicians make an accurate preoperative imaging diagnosis of gynandroblastoma with a juvenile granulosa cell component and plan an adequate treatment strategy for this rare, potentially malignant neoplasm. [ABSTRACT FROM AUTHOR]

The fabrication of a bilayer thin film by spin-coating on a π-conjugated polymer film is a crucial step in the processing of organic materials for optoelectronic applications. However, the process is difficult because it depends on a dramatic tuning of the polymer chemical structures used or an irreversible solid-state conversion of the chemical structure. Herein, we report a bilayer π-conjugated polymer film prepared by chemical modification of the polymer, i.e., BF 3 coordination-insolubilization by desorption solubilization. Poly[(9,9-dioctylfluorene-2,7-diyl)- alt -(pyridine-2,6-diyl)] (PPF8) is soluble in many organic solvents, but its film became insoluble owing to the BF 3 coordination. BF 3 -assisted insolubilization switching was easily investigated by color (fluorescence) changes. Further film formation on the insoluble film via spin-coating of a head-to-tail poly(3-hexylthiophene) (P3HT) solution produced the bilayer film. The PPF8 was able to remove the BF 3 coordination by triethylamine vapor treatment. [Display omitted] • BF 3 -Assisted insolubilization was demonstrated. • BF 3 -Assisted color and fluorescence changes were demonstrated. • Bilayer π-conjugated polymer films were successfully prepared by spin-coating for solubility switchable film. [ABSTRACT FROM AUTHOR]

Emission‐switchable fluorophores often include stimuli‐responsive units in their molecular structures. This strategy works well, but the applicable compounds are limited to the derivatives of several kinds of photochromic molecules such as diarylethene, azobenzene, and spiropyran. Here, this work presents a simple methodology based on a photoresponsive precipitant for achieving color‐switchable photoluminescence. A luminescent dye, cyano‐substituted oligo(phenylenevinylene) (COPV), features both twisted intramolecular charge transfer and aggregation‐induced emission shift properties, leading to the change in the luminescence color from green to red upon precipitation. The COPV, together with photoisomerizable precipitant azobenzene (C6), is doped into spherical droplets of epoxy resin (ER) in a liquid state. The photoisomerization of C6 induced by UV irradiation and heating alternatively precipitates out and dissolves COPV in ER and changes the photoluminescence color, while maintaining the optical microresonator properties. This study will open a promising way for assembling/disassembling novel emission color‐switchable systems. [ABSTRACT FROM AUTHOR]

Invited for this month′s cover is the collaborating group of Prof. Shotaro Hayashi at Kochi University of Technology. The cover picture shows anthracene molecules depicted among sakura blossoms at Kochi University of Technology (KUT). Anthracenes are arranged with falling petals, giving a beautiful image of the molecular crystal engineering field. The cover was designed by Yuto Hino. More information can be found in the Review by S. Hayashi and co‐workers. [ABSTRACT FROM AUTHOR]

Anthracene, crystal engineering, excimers, organic optoelectronics, phase transitions Keywords: anthracene; crystal engineering; excimers; organic optoelectronics; phase transitions EN anthracene crystal engineering excimers organic optoelectronics phase transitions 1 1 1 09/30/22 20220901 NES 220901 B The cover picture shows arrangements of anthracene crystals b : structural phase transitions in anthracene crystals have recently attracted much interest in a wide range of research areas in materials science. This Review discusses the engineering of anthracene, including its synthetic design, reactivities, and optical properties toward structural phase transitions of the crystals. [Extracted from the article]

Aim The aim of this study was to evaluate the value of magnetic resonance imaging (MRI) for the diagnosis and management of suspicious unruptured interstitial pregnancy. Material and Methods Only patients with unruptured interstitial pregnancy evaluated by MRI and observed for at least a year after surgery were included. Initial evaluation was performed by measurement of serum β-human chorionic gonadotrophin level and ultrasonography. In suspicious cases, emergency MRI was performed to diagnose interstitial pregnancies with the exclusion of rudimentary horn pregnancy and angular pregnancy. Three-dimensional computed tomographic (CT) angiography was additionally performed if the uteroplacental neovascularization needed to be evaluated. Then, management procedures were individually determined along with the need for preoperative transcatheter arterial chemoembolization for immediate devascularization, and for the local or systemic administration of methotrexate. Either laparoscopic cornuostomy or cornual resection was chosen to excise the gestational mass. Results Five consecutive women with unruptured interstitial pregnancy were enrolled. One case each of rudimentary horn pregnancy and angular pregnancy was excluded. Three-dimensional CT angiography was performed in three cases due to increased vascular flow on color Doppler ultrasonography. Preoperative devascularization by transcatheter arterial chemoembolization was performed in two cases, in which a prominent neovascularized gestational mass was identified. Uterine preservation was achieved by cornuostomy or cornual resection in all cases. Two patients with a desire to become pregnant conceived spontaneously thereafter, followed by successful cesarean birth. Conclusion This small case series emphasizes that precise localization of gestational products in the interstitial portion of the fallopian tube by MRI can facilitate the minimally invasive management of unruptured interstitial pregnancy for uterine preservation. [ABSTRACT FROM AUTHOR]