Pluripotent Features of Doubly Thiophene-Fused Benzodiphospholes as Organic Functional Materials

Linear ladder-type π-conjugated molecules have attracted much interest because of their intriguing physicochemical properties. To modulate their electronic structures, an effective strategy is to incorporate main-group elements into ladder-type π-conjugated molecules. In line with this strategy, a variety of ladder-type π-conjugated molecules with main-group elements have been synthesized to explore their potential utility as organic functional materials. In this context, phosphole-based π-conjugated molecules are highly attractive, owing to their unique optical and electrochemical properties, which arise from the phosphorus atom. Herein, the synthesis and physicochemical properties of doubly thiophene-fused benzodiphospholes, as a new class of phosphole-based ladder-type π-conjugated molecule, are reported. Systematic investigations into the physicochemical properties of doubly thiophene-fused benzodiphospholes revealed their pluripotent features: intense near-infrared fluorescence, excellent two-photon absorption property, and remarkably high electron-transporting ability. This study demonstrates the potential utility of doubly thiophene-fused benzodiphospholes as organic functional materials for biological imaging, nonlinear optics, organic transistors, and organic photovoltaics.     

Functional Sulfur‐Doped Buckybowls and Their Concave–Convex Supramolecular Assembly with Fullerenes

Buckybowls are fascinating components of supramolecular assemblies owing to their unique bowl‐shaped π‐surfaces. Herein we present a protocol for the functionalization of a sulfur‐doped buckybowl, trithiasumanene, via a brominated intermediate, from which thiolated trithiasumanenes were derived. The curved surface and electron‐donating properties of thiolated trithiasumanenes promote their ready assembly with fullerenes to form concave–convex complexes. The supramolecular assembly behavior in solution was investigated by NMR analysis. The structures of supramolecular complexes were unambiguously characterized by crystallography. The crystals of the concave–convex complexes showed high thermal stability and photoconductivity.     

Fusing Porphyrins and Phospholes: Synthesis and Analysis of a Phosphorus‐Containing Porphyrin

A phosphole‐fused porphyrin dimer, as a representative of a new class of porphyrins with a phosphorus atom, was synthesized for the first time. The porphyrin dimer exhibits remarkably broadened absorption, indicating effective π‐conjugation over the two porphyrins through the phosphole moiety. The porphyrin dimer possesses excellent electron‐accepting character, which is comparable to that of a representative electron‐accepting material, [60]PCBM. These results provide access to a new class of phosphorus‐containing porphyrins with unique optoelectronic properties.     

Metrological effectiveness of an analytical method for volatile organic compounds standard materials using post-column reaction GC/FID system

The metrological effectiveness of an analytical method using the post-column reaction GC/FID system was evaluated. The SI-traceable certified reference material (CRM), the eight ester phthalates mixture standard solution, was used as a sample. We assigned specific value to n-eicosane and it was used as an internal standard. A known quantity of n-eicosane was added to the CRM, and the mixture was measured with the post-column reaction GC/FID system. Six phthalate esters were chromatographically separated and determined. The assigned values by our system are in good agreement with the certified values of the CRM, and the combined uncertainties of the measurements by the present system were better than those of the CRM. Our method is classified as a primary ratio method and the specific values of many organic compounds can be assigned very precisely by using a small number of reference materials. Also, the method can make it possible to avoid the purity determination of raw materials and directly to assign their specific values after the preparation of the standard mixture. Conclusively, this post-column reaction GC/FID system is very effective for the chemical metrology.     

Calibration of an evaporative light-scattering detector as a mass detector for supercritical fluid chromatography by using uniform Poly(ethylene glycol) oligomers

The quantitativeness of an evaporative light-scattering detector (ELSD) for supercritical fluid chromatography (SFC) was evaluated by using an equimass mixture of uniform poly(ethylene glycol) (PEG) oligomers. Uniform oligomers, in which all molecules have an identical molecular mass, are useful for the accurate calibration of detectors. We calibrated the SFC-ELSD system for various concentrations and molecular masses by using an equimass mixture of PEG oligomers. ELSD not only showed a good linear response to the injected concentration over a wide concentration range, from 10(-4) to 10(-1)g/mL, but also showed a strong dependence on the molecular mass of the solute. By using chromatograms of the equimass mixture of uniform oligomers to calibrate SFC-ELSD, it was possible to determine exact values of not only the average mass but also the molecular-mass distribution for a PEG 1540 sample. The average molecular mass was shifted to a higher value by several percentage points after calibration of the ELSD.     

Tetraplatinum precursors for supramolecular assemblies: syntheses, crystal structures, and stereoselective self-assemblies of [Pt4(micro-OCOCH3)6(kappa4-N4-DArBp)] (DArBp = 1,3-bis(arylbenzamidinate)propane)

Treatment of the cisoid-capped complex [Pt(4)(micro-OCOCH(3))(6)(kappa(4)-N(4)-DAr'Bp)] (), which was obtained from the reaction of [Pt(4)(micro-OCOCH(3))(8)] (1) with Na(2)D(t)BuPhBp (D(t)BuPhBp = 1,3-bis(para-tert-butylphenylbenzamidinate)propane), with an equimolar amount of 1,1'-ferrocenedicarboxylic acid undergoes a stereoselective self-assembly to afford an indented-quadrangle tetramer [Pt(4)(micro-OCOCH(3))(4)(kappa(4)-N(4)-D(t)BuPhBp){Fe(C(5)H(4)COO)(2)}](4) as a single diastereomer.     

Photoinduced Charge‐Carrier Generation in Epitaxial MOF Thin Films: High Efficiency as a Result of an Indirect Electronic Band Gap?

For inorganic semiconductors crystalline order leads to a band structure which gives rise to drastic differences to the disordered material. An example is the presence of an indirect band gap. For organic semiconductors such effects are typically not considered, since the bands are normally flat, and the band‐gap therefore is direct. Herein we show results from electronic structure calculations demonstrating that ordered arrays of porphyrins reveal a small dispersion of occupied and unoccupied bands leading to the formation of a small indirect band gap. We demonstrate herein that such ordered structures can be fabricated by liquid‐phase epitaxy and that the corresponding crystalline organic semiconductors exhibit superior photophysical properties, including large charge‐carrier mobility and an unusually large charge‐carrier generation efficiency. We have fabricated a prototype organic photovoltaic device based on this novel material exhibiting a remarkable efficiency.     

Toward Ultralow-Bandgap Liquid Crystalline Semiconductors: Use of Triply Fused Metalloporphyrin Trimer-Pentamer as Extra-large π-Extended Mesogenic Motifs

In contrast with their dimeric homologue, triply fused zinc porphyrin trimer-pentamer, as extra-large π-extended mesogens, assemble into columnar liquid crystals (LCs) when combined with 3,4,5-tri(dodecyloxy)phenyl side groups (3?P(Zn) -5?P(Zn) , Figure?1). Their LC mesophases develop over a wide temperature range, namely, 41-280?°C (on heating) for 5?P(Zn) , and all adopt an oblique columnar geometry, typically seen in columnar LC materials involving strong mesogenic interactions. These LC materials are characterized by their wide light-absorption windows from the entire visible region up to a near infrared (NIR) region. Such ultralow-bandgap LC materials are chemically stable and serve as hole transporters, in which 5?P(Zn) gives the largest charge carrier mobility (2.4×10(-2) cm?V(-1) s(-1) ) among the series. Despite a big dimensional difference, they coassemble without phase separation, in which the resultant LC materials display essentially no deterioration of the intrinsic conducting properties.