10.術後逆流性食道炎の検討(第2報)(第526回千葉医学会例会・第9回佐藤外科例会)

Engineering of novel systems capable of efficient energy capture and transfer in a predesigned pathway could potentially boost applications varying from organic photovoltaics to catalytic platforms and have implications for energy sustainability and green chemistry. While light-harvesting properties of different materials have been studied for decades, recently, there has been great progress in the understanding and modeling of short- and long-range energy transfer processes through utilization of metal–organic frameworks (MOFs). In this Forum Article, the recent advances in efficient multiple-chromophore coupling in well-defined metal–organic materials through mimicking a protein system possessing near 100% energy transfer are discussed. Utilization of a MOF as an efficient replica of a protein β-barrel to maintain chromophore emission was also demonstrated. Furthermore, we established a novel dependence of a photophysical response on an electronic configuration for chromophores with the benzylidene imidazolinone core. For that, we prepared 16 chromophores, in which the benzylidene imidazolinone core was modified with electron-donating and electron-withdrawing substituents. To establish the structure-dependent photophysical properties of the prepared chromophores, 11 novel molecular structures were determined by single-crystal X-ray diffraction. These findings allow one to predict the chromophore emission profile inside a rigid framework as a function of the substituent, a key parameter for achieving the spectral overlap necessary to study and increase resonance energy transfer efficiency in MOF-based materials

Photoredox-Assisted Reductive Cross-Coupling: Mechanistic Insight into Catalytic Aryl–Alkyl Cross-Couplings

Here, we describe a photoredox-assisted catalytic system for the direct reductive coupling of two carbon electrophiles. Recent advances have shown that nickel catalysts are active toward the coupling of sp³-carbon electrophiles and that well-controlled, light-driven coupling systems are possible. Our system, composed of a nickel catalyst, an iridium photosensitizer, and an amine electron donor, is capable of coupling halocarbons with high yields. Spectroscopic studies support a mechanism where under visible light irradiation the Ir photosensitizer in conjunction with triethanolamine are capable of reducing a nickel catalyst and activating the catalyst toward cross-coupling of carbon electrophiles. The synthetic methodology developed here operates at low 1 mol % catalyst and photosensitizer loadings. The catalytic system also operates without reaction additives such as inorganic salts or bases. A general and effective sp²–sp³ cross-coupling scheme has been achieved that exhibits tolerance to a wide array of functional groups

Homochiral, Helical Coordination Complexes of Lanthanides(III) and Mixed-Metal Lanthanides(III): Impact of the 1,8-Naphthalimide Supramolecular Tecton on Structure, Magnetic Properties, and Luminescence

The reactions of the lithium salt of (<i>S</i>)-2-(1,8-naphthal­imido)-3-hydroxy­propanoate (<b>L</b>_<b>ser</b>^–), an enantio­pure carboxylate ligand containing a 1,8-naphthal­imide π···π stacking supra­molecular tecton and an alcohol functional group, with La­(NO₃)₃, Ce­(NO₃)₃, SmCl₃, Eu­(NO₃)₃, Gd­(NO₃)₃, Tb­(NO₃)₃, and Dy­(NO₃)₃ under solvo­thermal conditions (water/​ethanol) produced single crystals (characterized by single-crystal X-ray crystallography) of [La₃­(<b>L</b>_<b>ser</b>)₈­(OH)­(H₂O)]·​(H₂O,​EtOH)_<i>x</i> (<b>1</b>), [Ce₃­(<b>L</b>_<b>ser</b>)₈­(OH)­(H₂O)]·​(H₂O,​EtOH)_<i>x</i> (<b>2</b>), [Sm₃­(<b>L</b>_<b>ser</b>)₈­(OEt)]·​(H₂O,​EtOH)_<i>x</i> (<b>3</b>), [Eu₃­(<b>L</b>_<b>ser</b>)₈­(OEt)]·​(H₂O,​EtOH)_<i>x</i> (<b>4</b>), [Gd₃­(<b>L</b>_<b>ser</b>)₈­(OEt)]·​(H₂O,​EtOH)_<i>x</i> (<b>5</b>), [Tb₃­(<b>L</b>_<b>ser</b>)₈­(OEt)]·​(H₂O,​EtOH)_<i>x</i> (<b>6</b>), and [Dy₃­(<b>L</b>_<b>ser</b>)₈­(OEt)]·​(H₂O,​EtOH)_<i>x</i> (<b>7</b>), respectively. Mixed-metal complexes [Ce_2.3Tb_0.7­(<b>L</b>_<b>ser</b>)₈(OH)]·​(H₂O,​EtOH)_<i>x</i> (<b>8</b>), [Gd_0.4Tb_2.6­(<b>L</b>_<b>ser</b>)₈­(OEt)]·​(H₂O,​EtOH)_<i>x</i> (<b>9</b>), and [Ce_1.4Gd_0.3Tb_1.3­(<b>L</b>_<b>ser</b>)₈(OH)]·​(H₂O,​EtOH)_<i>x</i> (<b>10</b>) were prepared by using two or more types of lanthanides in the solvo­thermal reactions (additional mixed-metal complexes were prepared and characterized by ICP-MS). Single crystals of compounds <b>1</b>–<b>10</b> are isostructural: trinuclear, carboxylate-bonded helicates organized by the non-covalent, π···π stacking interactions of the 1,8-naphthal­imide groups into <i>inter­twined M</i> helices, with a pitch of 56 Å, that are further arranged into a three-dimensional supra­molecular framework by additional π···π stacking interactions. Magnetic measurements of several compounds were as expected for the metal(s) present, indicating no significant interactions between metals within the helicates. The Ce complex <b>2</b> showed weak anti­ferro­magnetic ordering below 50 K. All of the complexes, with the exception of <b>2</b>, showed luminescence based on the 1,8-naphthal­imide group. Complex <b>2</b> has no emission, and complexes with mixed Ce/Tb ratios showed significant quenching of the naphthal­imide-based luminescence, as quantitated with solid-state, absolute quantum yield measurements of these mixed-metal and the pure metal complexes. Lanthanide-based luminescence was only observed for the Eu complex <b>4</b>

Zinc Paddlewheel Dimers Containing a Strong π···π Stacking Supramolecular Synthon: Designed Single-Crystal to Single-Crystal Phase Changes and Gas/Solid Guest Exchange

The ligand 4-(1,8-naphthalimido)benzoate, <b>L</b>_<b>C4</b>^<b>–</b>, containing a linear link between the strong π···π stacking 1,8-naphthalimide supramolecular synthon and the carboxylate donor group, reacts with Zn(O₂CCH₃)₂(H₂O)₂ in the presence of dimethylsulfoxide (DMSO) to yield [Zn₂(<b>L</b>_<b>C4</b>)₄(DMSO)₂]·2(CH₂Cl₂). This compound contains the “paddlewheel” Zn₂(O₂CR)₄ secondary building unit (SBU) that organizes the rigid phenylene and naphthalimide rings of the carboxylate ligands in a square arrangement. The supramolecular architecture is dominated by π···π stacking interactions between naphthalimide rings of one dimer with four adjacent dimers, essentially at right angles, forming an open three-dimensional network structure. Two symmetry equivalent networks of this type interpenetrate generating overall a densely packed three-dimensional, 2-fold interpenetrated architecture in which the CH₂Cl₂ solvate molecules are trapped in isolated pockets. Upon cooling, single crystals of [Zn₂(<b>L</b>_<b>C4</b>)₄(DMSO)₂]·2(CH₂Cl₂) undergo two distinct crystallographic phase transitions, as characterized by X-ray diffraction at different temperatures, without loss of crystallinity. These two new phases have supramolecular structures very similar to the room temperature structure, but changes in the ordering of the CH₂Cl₂ solvate cause shifting of the naphthalimide rings and a lowering of the symmetry. Crystals of [Zn₂(<b>L</b>_<b>C4</b>)₄(DMSO)₂]·2(CH₂Cl₂) undergo a single-crystal to single-crystal gas/solid guest exchange upon exposure to atmospheric moisture, or faster if placed under vacuum or heated under dry gas to 100 °C, followed by atmospheric moisture, to yield [Zn₂(<b>L</b>_<b>C4</b>)₄(DMSO)₂]·3.9(H₂O). The molecular and supramolecular structures of this new compound are very similar to the dichloromethane adduct, with now the water molecules encapsulated into the framework. The remarkable feature of both the phase changes and exchange of solvates is that this robust network is not porous; local distortions (ring slippage and tilting changes) of the π···π stacking interactions of the naphthalimide rings that organize these structures allow these changes to take place without the loss of crystallinity. The complexes [Zn₂(<b>L</b>_<b>C4</b>)₄(DMSO)₂]·2(CH₂Cl₂) and [Zn₂(<b>L</b>_<b>C4</b>)₄(DMSO)₂]·3.9(H₂O) show green emission in the solid state

Zinc Paddlewheel Dimers Containing a Strong π···π Stacking Supramolecular Synthon: Designed Single-Crystal to Single-Crystal Phase Changes and Gas/Solid Guest Exchange

The ligand 4-(1,8-naphthalimido)benzoate, <b>L</b>_<b>C4</b>^<b>–</b>, containing a linear link between the strong π···π stacking 1,8-naphthalimide supramolecular synthon and the carboxylate donor group, reacts with Zn(O₂CCH₃)₂(H₂O)₂ in the presence of dimethylsulfoxide (DMSO) to yield [Zn₂(<b>L</b>_<b>C4</b>)₄(DMSO)₂]·2(CH₂Cl₂). This compound contains the “paddlewheel” Zn₂(O₂CR)₄ secondary building unit (SBU) that organizes the rigid phenylene and naphthalimide rings of the carboxylate ligands in a square arrangement. The supramolecular architecture is dominated by π···π stacking interactions between naphthalimide rings of one dimer with four adjacent dimers, essentially at right angles, forming an open three-dimensional network structure. Two symmetry equivalent networks of this type interpenetrate generating overall a densely packed three-dimensional, 2-fold interpenetrated architecture in which the CH₂Cl₂ solvate molecules are trapped in isolated pockets. Upon cooling, single crystals of [Zn₂(<b>L</b>_<b>C4</b>)₄(DMSO)₂]·2(CH₂Cl₂) undergo two distinct crystallographic phase transitions, as characterized by X-ray diffraction at different temperatures, without loss of crystallinity. These two new phases have supramolecular structures very similar to the room temperature structure, but changes in the ordering of the CH₂Cl₂ solvate cause shifting of the naphthalimide rings and a lowering of the symmetry. Crystals of [Zn₂(<b>L</b>_<b>C4</b>)₄(DMSO)₂]·2(CH₂Cl₂) undergo a single-crystal to single-crystal gas/solid guest exchange upon exposure to atmospheric moisture, or faster if placed under vacuum or heated under dry gas to 100 °C, followed by atmospheric moisture, to yield [Zn₂(<b>L</b>_<b>C4</b>)₄(DMSO)₂]·3.9(H₂O). The molecular and supramolecular structures of this new compound are very similar to the dichloromethane adduct, with now the water molecules encapsulated into the framework. The remarkable feature of both the phase changes and exchange of solvates is that this robust network is not porous; local distortions (ring slippage and tilting changes) of the π···π stacking interactions of the naphthalimide rings that organize these structures allow these changes to take place without the loss of crystallinity. The complexes [Zn₂(<b>L</b>_<b>C4</b>)₄(DMSO)₂]·2(CH₂Cl₂) and [Zn₂(<b>L</b>_<b>C4</b>)₄(DMSO)₂]·3.9(H₂O) show green emission in the solid state

Homochiral, Helical Coordination Complexes of Lanthanides(III) and Mixed-Metal Lanthanides(III): Impact of the 1,8-Naphthalimide Supramolecular Tecton on Structure, Magnetic Properties, and Luminescence

The reactions of the lithium salt of (<i>S</i>)-2-(1,8-naphthal­imido)-3-hydroxy­propanoate (<b>L</b>_<b>ser</b>^–), an enantio­pure carboxylate ligand containing a 1,8-naphthal­imide π···π stacking supra­molecular tecton and an alcohol functional group, with La­(NO₃)₃, Ce­(NO₃)₃, SmCl₃, Eu­(NO₃)₃, Gd­(NO₃)₃, Tb­(NO₃)₃, and Dy­(NO₃)₃ under solvo­thermal conditions (water/​ethanol) produced single crystals (characterized by single-crystal X-ray crystallography) of [La₃­(<b>L</b>_<b>ser</b>)₈­(OH)­(H₂O)]·​(H₂O,​EtOH)_<i>x</i> (<b>1</b>), [Ce₃­(<b>L</b>_<b>ser</b>)₈­(OH)­(H₂O)]·​(H₂O,​EtOH)_<i>x</i> (<b>2</b>), [Sm₃­(<b>L</b>_<b>ser</b>)₈­(OEt)]·​(H₂O,​EtOH)_<i>x</i> (<b>3</b>), [Eu₃­(<b>L</b>_<b>ser</b>)₈­(OEt)]·​(H₂O,​EtOH)_<i>x</i> (<b>4</b>), [Gd₃­(<b>L</b>_<b>ser</b>)₈­(OEt)]·​(H₂O,​EtOH)_<i>x</i> (<b>5</b>), [Tb₃­(<b>L</b>_<b>ser</b>)₈­(OEt)]·​(H₂O,​EtOH)_<i>x</i> (<b>6</b>), and [Dy₃­(<b>L</b>_<b>ser</b>)₈­(OEt)]·​(H₂O,​EtOH)_<i>x</i> (<b>7</b>), respectively. Mixed-metal complexes [Ce_2.3Tb_0.7­(<b>L</b>_<b>ser</b>)₈(OH)]·​(H₂O,​EtOH)_<i>x</i> (<b>8</b>), [Gd_0.4Tb_2.6­(<b>L</b>_<b>ser</b>)₈­(OEt)]·​(H₂O,​EtOH)_<i>x</i> (<b>9</b>), and [Ce_1.4Gd_0.3Tb_1.3­(<b>L</b>_<b>ser</b>)₈(OH)]·​(H₂O,​EtOH)_<i>x</i> (<b>10</b>) were prepared by using two or more types of lanthanides in the solvo­thermal reactions (additional mixed-metal complexes were prepared and characterized by ICP-MS). Single crystals of compounds <b>1</b>–<b>10</b> are isostructural: trinuclear, carboxylate-bonded helicates organized by the non-covalent, π···π stacking interactions of the 1,8-naphthal­imide groups into <i>inter­twined M</i> helices, with a pitch of 56 Å, that are further arranged into a three-dimensional supra­molecular framework by additional π···π stacking interactions. Magnetic measurements of several compounds were as expected for the metal(s) present, indicating no significant interactions between metals within the helicates. The Ce complex <b>2</b> showed weak anti­ferro­magnetic ordering below 50 K. All of the complexes, with the exception of <b>2</b>, showed luminescence based on the 1,8-naphthal­imide group. Complex <b>2</b> has no emission, and complexes with mixed Ce/Tb ratios showed significant quenching of the naphthal­imide-based luminescence, as quantitated with solid-state, absolute quantum yield measurements of these mixed-metal and the pure metal complexes. Lanthanide-based luminescence was only observed for the Eu complex <b>4</b>

Understanding the Formation of Salt-Inclusion Phases: An Enhanced Flux Growth Method for the Targeted Synthesis of Salt-Inclusion Cesium Halide Uranyl Silicates

Salt-inclusion compounds (SICs) are known for their structural diversity and their potential applications, including luminescence and radioactive waste storage forms. Currently, the majority of salt-inclusion phases are grown serendipitously and the targeted growth of SICs has met with only moderate success. We report an enhanced flux growth method for the targeted growth of SICs. Specifically, the use of (1) metal halide reagents and (2) reactions with small surface area to volume ratios are found to favor the growth of salt-inclusion compounds over pure oxides and thus enable a more targeted synthetic route for their preparation. The Cs–X–U–Si–O (X = F, Cl) pentanary phase space is used as a model system to demonstrate the generality of this enhanced flux method approach. Single crystals of four new salt-inclusion uranyl silicates, [Cs₃F]­[(UO₂)­(Si₄O₁₀)], [Cs₂Cs₅F]­[(UO₂)₂(Si₆O₁₇)], [Cs₉Cs₆Cl]­[(UO₂)₇(Si₆O₁₇)₂(Si₄O₁₂)], and [Cs₂Cs₅F]­[(UO₂)₃(Si₂O₇)₂], were grown using this enhanced flux growth method. A detailed discussion of the factors that favor salt-inclusion phases during synthesis and why specifically uranyl silicates make excellent frameworks for salt-inclusion phases is given

A Family of A‑Site Cation-Deficient Double-Perovskite-Related Iridates: Ln₉Sr₂Ir₄O₂₄ (Ln = La, Pr, Nd, Sm)

The compositions of the general formula Ln_{11–<i>x</i>}Sr_<i>x</i>Ir₄O₂₄ (Ln = La, Pr, Nd, Sm; 1.37 ≥ <i>x</i> ≥ 2) belonging to a family of A-site cation-deficient double-perovskite-related oxide iridates were grown as highly faceted single crystals from a molten strontium chloride flux. Their structures were determined by single-crystal X-ray diffraction. On the basis of the single-crystal results, additional compositions, Ln₉Sr₂Ir₄O₂₄ (Ln = La, Pr, Nd, Sm), were prepared as polycrystalline powders via solid-state reactions and structurally characterized by Rietveld refinement. The compositions Ln₉Sr₂Ir₄O₂₄ (Ln = La, Pr, Nd, Sm) contain Ir­(V) and Ir­(IV) in a 1:3 ratio with an average iridium oxidation state of 4.25. The single-crystal compositions La_9.15Sr_1.85Ir₄O₂₄ and Pr_9.63Sr_1.37Ir₄O₂₄ contain relatively less Ir­(V), with the average iridium oxidation states being 4.21 and 4.09, respectively. The magnetic properties of Ln₉Sr₂Ir₄O₂₄ (Ln = La, Pr, Nd, Sm) were measured, and complex magnetic behavior was observed in all cases at temperatures below 30 K

Metal- and Ligand-Centered Reactivity of <i>meta</i>-Carboranyl-Backbone Pincer Complexes of Rhodium

We report the synthesis of the chelating phosphinite-arm carboranyl POBOP-H (POBOP = 1,7-OP­(<i>i</i>-Pr)₂-<i>m</i>-carboranyl) ligand precursor, preparation of its rhodium complexes, and their reactivity in oxidative addition/reductive elimination reactions. The oxidative addition of iodobenzene to the low-valent (POBOP)­Rh­(PPh₃) resulted in the selective formation of the 16-electron complex (POBOP)­Rh­(Ph)­(I), featuring a highly strained exohedral rhodium–boron bond. The complex (POBOP)­Rh­(Ph)­(I) is the first example of a B-carboranyl aryl metal complex, which is a proposed intermediate in metal-promoted B–C coupling reactions. The complex (POBOP)­Rh­(Ph)­(I) was selectively and directly converted, in the presence of acetonitrile, to (POB­(BPh)­OP)­Rh­(H)­(I)­(CH₃CN) (POB­(BPh)­OP = 1,7-OP­(<i>i</i>-Pr)₂-2-Ph-<i>m</i>-carboranyl) through unprecedented cascade reductive elimination of the phenyl-<i>B</i>-carboranyl and the oxidative addition of a vicinal B–H bond of the boron cluster to the metal center, exhibiting both metal- and cluster-centered reactivity

Comprehensive Experimental Study of N<i>-</i>Heterocyclic π‑Stacking Interactions of Neutral and Cationic Pyridines

A comprehensive experimental study was carried out by measuring the relative strengths of parallel π-stacking interactions of N<i>-</i>heterocycles with nonheterocycles. A versatile and rigid model system was developed, which was in equilibrium between a “closed” conformation that forms an intramolecular π-stacking interaction and an “open” conformation that cannot form the interaction. First, the formation and geometries of the intramolecular N<i>-</i>heterocyclic π-stacking interactions were verified by X-ray crystallography. Next, the closed/open ratios were measured in solution via integration of the ¹H NMR spectra, providing an accurate comparison of the N-heterocyclic π-stacking interactions. The synthetic versatility of this model system enabled the systematic and comprehensive comparison of the influences of position, charge, and substituent effects of the nitrogen atom of the N-heterocycles within a single model system. The π-stacking interactions of the neutral N-heterocyclic rings were slightly stronger than that of nonheterocyclic rings. Cationic N-heterocycles formed significantly stronger π-stacking interactions than neutral N-heterocycles. The position of the nitrogen atom also had a strong influence on the stability of N-heterocyclic π-stacking complexes. Interestingly, opposite stability trends were observed for neutral and cationic N-heterocycles. For neural N-heterocycles, geometries with the nitrogen away from the π-face of the opposing ring were the more stable. For cationic N-heterocycles, geometries with the nitrogen close to the π-face of the opposing ring were the more stable. Finally, N-methylated heterocycles consistently formed stronger π-stacking interactions than N-protonated heterocycles