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The [2+2] photocycloaddition of alkenyl-tethered 1H-pyrrolo[2,3-b]pyridine derivatives sensitized with 3',4'-dimethoxyacetophenone under irradiation by a high-pressure mercury lamp through Pyrex glass was dramatically accelerated by the addition of Lewis acids, preferably Mg(OTf)(2), to give the products stereoselectively in high yields. The reaction without a Lewis acid gave only small amounts of the [2+2] cycloaddition products. Conformational fixation of the substrates by coordination with a Lewis acid was presumed to facilitate the cycloaddition.

We successfully demonstrated that Friedel−Crafts‐type allylation of phenol derivatives and allylic phosphates is catalyzed by the AgTFA/trimethylsilyl cyanide (Me3SiCN) and Pd(OAc)2/Me3SiCN combined systems to afford the C‐allylated product in a highly regioselective manner. The corresponding silyl cyanometallates generated in situ are proposed to be the active catalytic species. Lewis acidity of the reversibly formed ion pairs is appropriately regulated for this reaction. The para‐allylated anisole and phenol derivatives are selectively obtained. The para‐substituted ones are converted to the ortho‐allylated products. The reactivity of the catalytic systems is strongly dependent on the electronic nature of both electrophile and nucleophile. Substitution of an aromatic ring on the allylic phosphate is essential for the reaction. Thus, the competitive reaction of a 1 : 1 mixture of cinnamyl and simple allyl phosphates affords only the cinnamyl‐substituted product.

Two types of chiral Ru(II) complexes, each with two kinds of ligands, have been designed and utilized as catalysts for several asymmetric reactions under appropriate conditions. The first type, the...

The DIPSkewphos/PICA derivative-Ru(II) complexes catalyzed asymmetric hydrogenation of significantly sterically hindered 2',3',4',5',6'-pentamethylacetophenone, which was not reduced with NaBH4 at 25 degrees C, with a substrate-to-catalyst molar ratio (S/C) of 2000 under 50 atm of H-2 in a base-containing 2-propanol to afford the alcohol in 99% ee quantitatively. A series of polysubstituted aromatic ketones was smoothly reacted with an S/C of 300-10,000 under 10-50 atm of H-2, yielding the alcoholic products in up to 99% ee. The catalyst system achieved an industrial-scale (50 kg) hydrogenation of 2',6'-dichloro-3'-fluoroacetophenone, affording the alcohol in 96% isolated yield and in 98% ee. The obtained alcoholic product is known as a key intermediate for the synthesis of the medicine crizotinib.

The asymmetric hydrogenation of aromatic γ- and δ-keto esters into optically active hydroxy esters or diols under the catalysis of a novel DIPSkewphos/3-AMIQ-RuII complex was studied. Under the optimized conditions (8 atm H2 , Ru complex/t-C4 H9 OK=1:3.5, 25 °C) the γ- and δ-hydroxy esters (including γ-lactones) were obtained quantitatively with 97-99 % ee. When the reaction was conducted under somewhat harsh conditions (20 atm H2 , [t-C4 H9 OK]=50 mm, 40 °C), the 1,4- and 1,5-diols were obtained predominantly with 95-99 % ee. The reactivity of the ester group was notably dependent on the length of the carbon spacer between the two carbonyl moieties of the substrate. The reaction of β- and ϵ-keto esters selectively afforded the hydroxy esters regardless of the reaction conditions. This catalyst system was applied to the enantioselective and regioselective (for one of the two ester groups) hydrogenation of a γ-ϵ-diketo diester into a trihydroxy ester.

Double asymmetric hydrogenation of linear β,β-disubstituted α,β-unsaturated ketones catalyzed by the DM-SEGPHOS/DMAPEN/RuII complex with t-C4H9OK afforded the γ-substituted secondary alcohols in high diastereo- and enantioselectivities. Some mechanistic experiments suggested that two different reactive species, type (I) and (II), were reversibly formed in this catalytic system: Type (I) with the diamine ligand DMAPEN enantioselectively hydrogenated the enones into the chiral allylic alcohols, and type (II) without the diamine ligand diastereoselectively hydrogenated the allylic alcohols into the γ-substituted secondary alcohols. This dual catalysis protocol was successfully applied to the reaction of a variety of aliphatic- and aromatic-substituted enone substrates.

Catalytic chemoselective hydrogenation of organic azides using palladium nanoparticles stabilized by alkyne derivatives was studied. A broad range of aromatic and aliphatic azides were smoothly reduced to the corresponding amines in excellent yields with a quite small amount of the catalyst. Hydrogenation of 3-phenylpropylazide gave 3-phenylpropylamine almost quantitatively with a substrate-to-palladium molar ratio (S/Pd) of 12,900 under 8 atm of H-2. The reaction under 1 atm of H2 also proceeded smoothly with an S/Pd of 1000. Several reduction-sensitive functional groups, such as carbonyl, halide, benzylic OH, and aliphatic nitro were well tolerated under the reaction conditions. (C) 2016 Elsevier Ltd. All rights reserved.

Catalytic asymmetric hydrogenation of ketones through the "metal-ligand cooperative mechanism" has been improved in terms of the efficiency, stereoselectivity, and scope of substrates by varying the arrangement of the catalyst structure and reaction conditions. Imino compounds are also smoothly converted to the optically active amines with appropriate catalysts. This type of catalyst exhibits excellent performance on the asymmetric isomerization of primary allylic alcohols into the optically active aldehydes. This personal account describes recent progress on these topics.

Aza-Diels–Alder-type cycloaddition reactions between a range of N-arylimines and functionalized alkenes were effectively catalyzed by the Cr(III)/bipyridine complex under irradiation of blue light, to give the corresponding 1,2,3,4-tetrahydroquinoline derivatives in high yields with excellent diastereoselectivity. Typically, the reaction of benzylideneaniline with 1-vinyl-2-pyrrolidinone proceeded smoothly with a substrate-to-catalyst molar ratio (S/C) of 1000 and completed within 4 h at room temperature (20–25 °C), affording the cycloaddition product in 97% yield.

Irradiation of 3-(hexa-4,5-dienyl)indole derivatives in the presence of 3',4'-dimethoxyacetophenone by a high-pressure mercury lamp through Pyrex glass gave the corresponding [2+2] cycloaddition products stereoselectively in high yields. The major product was a methylenecyclobutane-fused angular tetracyclic spiroindoline derivative produced by the [2+2] cycloaddition through a parallel orientation. The minor product was a hexahydromethanocarbazole derivative through a crossed orientation. Electron-withdrawing substituents, such as acyl or alkoxycarbonyl, on the indole nitrogen were suitable for this reaction. (C) 2019 Elsevier Ltd. All rights reserved.

The combined systems of phenylglycinate/­BINAP/Ru(II) complex and Li compounds have been found to act as highly reactive and enantioselective catalysts for cyanosilylation and hydrocyanation of aldehydes, α-keto esters, α,β-unsaturated ketones, and N-protected aldimines. In this account, we describe the concept of catalyst design, the catalytic efficiency of the novel combined systems in the asymmetric cyanation, and the proposed reaction pathway based on the spectral analysis data. 1 Introduction 2 Cyanosilylation of Aldehydes and Ketones Catalyzed by LiCl 3 Asymmetric Cyanosilylation of Aldehydes and α-Keto ­Esters 3.1 Design of Chiral Ru–Li Combined Catalyst Systems 3.2 Cyanosilylation of Aldehydes 3.3 Cyanosilylation of α-Keto Esters 4 Asymmetric Hydrocyanation of Aldehydes, α,β-Unsaturated Ketones, and Aldimines 4.1 Hydrocyanation of Aldehydes 4.2 Conjugate Cyanation of α,β-Unsaturated Ketones 4.3 Strecker-Type Reaction 5 Mechanistic Considerations for Cyanosilylation of Aldehydes and Ketones 5.1 Achiral Reaction Catalyzed by LiCl 5.2 Asymmetric Reaction with the Chiral Ru–Li Combined Catalyst 6 Conclusion

In evaluation of wind-induced responses through time-history analysis based on stationary random process, its responsive value must be dealt with numerous numbers of statistics. However, the designing value is often determined from the small number of samples because of limited time and expense in practice. Therefore, it is important and necessary to grasp dispersion of wind response from small number of samples. In this paper, the dispersion of wind forces and wind-induced responses are investigated from wind tunnel tests. Then, the influence on wind responses due to the difference in the number of samples used as an ensemble average is elucidated.

We have measured the temperature dependence of specific heat, C ( T ), for Ag deposited YBCO coated conductor (YCC),YCC reinforced by a thin Cutape (YCC-Cu), andthe Hastelloy substrate with buffer layer. C ( T ) of HastelloyC–276 with buffer layer agrees well with the reported oneof HastelloyC-276, indicating that the contribution of the buffer layer to the measured C ( T ) is negligibly small. C ( T )of both YCC and YCC-Cu tapes was successfully reproduced by the simple sum rule using the C ( T ) values reported for Hastelloy, Ag and Cu. The results demonstrate that C ( T ) of various YCC tapes can be estimated using the reported C ( T )of constitutional materials. The estimated thermal diffusivity, a = K/ C , at 300K of YCC, which was estimated using the thermal conductivity, K, did not agree with the reported a of Ag. This resultwas in consistent with the fact that the applied heat flew through the Aglayer, suggesting that a relation of a = K/ C for homogeneous material cannot be applicable for the layered material such as YCC.

RE1Ba2Cu3O7-δ(RE: Rare Earth, Y Gd and so on, REBCO) superconducting tapes have great performance in critical current density, J c, property even at liquid nitrogen temperature. However, it is necessary to enhance a current capacity for practical use. We proposed the configuration of parallel conductors and adopted it to several pieces of test transformers, e.g. a 66kV-2MVA one for a power grid, 25kV-4MVA one for a Shinkansen rolling stock, and so on. The constituent strands of parallel conductors need to be insulated and transposed for the sake of uniform current distribution and low ac loss. In case the transposition points deviate from the optimum ones, shielding current is induced according to the interlinkage magnetic flux of the twisted loop enclosed by the insulated strands and the contact resistances at the terminals. It produces an additional ac loss. Up to now, we have studied in the simple situation where parallel conductors are exposed to a uniform ac magnetic field. In this study, we studied the additional ac losses in the case that two-strand parallel conductors are located in non-uniform magnetic field. We derived theoretical expressions of the additional ac losses and discussed the dependences of them on the non-uniformity in magnetic field, the deviation length of the transposition point from the optimum one, and so on.

RE1Ba2Cu3O7-≏(RE: Rare Earth, Y, Gd and so on, REBCO) superconducting tapes have high performance in critical current density, Jc , property even in high magnetic field and at liquid nitrogen temperature. We have proposed the ac loss reduction method of REBCO superconducting tape, which are the combination of a laser–scribing into a multifilamentary structure and a special winding process. Using the ac loss reduction technique, we could realize REBCO superconducting transformers with the advantage of light weight, compactness and high efficiency in comparison to conventional one. Further we aim to add a current limiting function to REBCO superconducting transformers. Recently we manufactured a 10kVA four-winding transformer with REBCO tapes. We carried out a sudden short circuit test and investigated the response against the fault excess current. We developed a numerical analysis program so as to quantitatively simulate the phenomena taking into account of a flux-flow resistance. As a result, it was shown that the whole of the REBCO winding did not shift to normal state even though the current exceeded the critical current all over the length. In this paper, we report the outlines.

There are high expectations for RE123 wires to be used as future commercial superconductors in the future because of their excellent performance under high magnetic fields and of low cost capabilities. ISTEC, national institutes, universities and companies are taking part in a Japanese national project on electric power devices known as, "Materials & Power Applications of Coated Conductors (M-PACC)". The target applications of the project are SMES, cables and transformers. ISTEC, Fujikura, Showa, Sumitomo and Furukawa are developing RE123 wires for mass-production using various fabrication processes. One of the most important characteristics for practical superconducting wires is, the bending-strain dependence of the critical current. The IC dependencies of RE123 wires for various bending strains were measured using the "Goldacker type" continuous bending apparatus. For tensile bending with the superconductor layer on the outside of the bend, the diameter of the 95% IC retentions was approximately 20 mm for all wires. On the other hand, for compressive bending with the superconductor layer on the inside of the bend, the IC dependencies for the bending diameter were each different. The reversibility strain under bending and straightening was also evaluated using the continuous bending apparatus. These results demonstrate that the IC dependencies for the bending diameter of all wires are suitable for the applications of the M-PACC project.

There are expectations for high-temperature superconducting (HTS) power cables as a compact cable with large capacity and low-loss power transmission. Recently, the stable manufacture of many long REBCO (RE = rare-earth element) tapes has been achieved. REBCO tapes have a high critical-current density, and the AC loss resulting from the parallel magnetic field is extremely small because of the thin-film structure of the superconducting layer. The basis of the M-PACC (Materials & Power Applications of Coated Conductors) project is to develop a process technology for fabricating REBCO tapes and promote development aiming toward the commercialization of superconducting cables using REBCO tapes. Two types of HTS cables are being developing as part of this project. These cables have superior transmission efficiency, lower loss and larger capacity than existing power cables. One is a 66 kV/5 kA three-core large-current cable and the other is a 275 kV/3 kA single-core high-voltage cable. There are several development targets. We examined factors such as AC loss, thermal characteristics of the cables under over-current and the optimum cable design. This paper provides an overview of the project and describes its progress.

Ru complexes with chiral diphosphines and amine-based ligands achieve high catalytic activity and enantioselectivity for the hydrogenation of ketones under neutral to slightly basic conditions. The chiral environment is controllable by changing the combination of these two ligands. A concerted six-membered transition state is proposed to be the origin of the high reactivity. The eta(6)-arene/TsDPEN-Ru and MsDPEN-Cp(*)Ir catalysts effect the asymmetric reaction under slightly acidic conditions. A variety of chiral secondary alcohols are obtained in high enantiomeric excess.

Asymmetric hydrogenation of aromatic heterocyclic ketones catalyzed by Cp*Ir(OTf)(Msdpen) (MsDPEN = N-(methanesulfonyl)-1,2-diphenylethylenediamine) affords the heterocyclic alcohols in 93% to > 99% ee. The reaction is conducted in a methanolic solution with a substrate-to-catalyst molar ratio of 200-5000 under 15 atm of H2. The heterocyclic rings of substrates are left intact.

This paper describes equations for estimating maximum along-wind load on the structural design of a wind turbine tower in the operational condition. Some parameters are derived from field measurements and wind tunnel tests. Furthermore, the wind load estimation method is based on the gust effect factor method. First, the application terms and fundamental wind load estimation methods are shown. Second, the modeling of parameters of the equations is investigated. Lastly, the gust effect factors and maximum overturning moments are calculated using the suggested equations, and compared with field measurements. The estimated maximum along-wind loads agree with the field measurements, thus confirming the applicability of the equations.

This study investigates the effects of inclination angle and yaw angle for wind forces acting on inclined circular cylinders. In this study, wind forces per unit length acting on the cylinders are measured simultaneously at all positions by using a manifold system. From this study, the following results are obtained; (1) The modal wind forces acting on the inclined circular cylinders and the Strouhal number are followed to the Cosine Rule or the Independence Principle. Those data are characterized by equivalent yaw angle, which combined with inclination angle and yaw angle. (2) The fluctuating across wind forces transmit from up-stream side to down-stream side in a constant speed. The transmission speed of the fluctuating across wind forces is able to be approximated to a liner function of equivalent yaw angle. (3) The characteristics of wind forces in a uniform flow and a turbulent flow are almost same.

This paper discusses an analytical method for estimating wind pressures under roof tiles induced by the interaction between internal pressures and external pressures. First, internal pressures on roof models, whose internal volume and gaps have values equivalent to those of a real roof tile, were measured in wind tunnel tests. Next, the internal pressures were estimated analytically by applying a non-steady Bernoulli equation to the flow through the gap. The validity of the analytical method was examined by comparison with results of the wind tunnel tests. Finally, internal pressures on a whole roof were deduced from simultaneous external pressures through a roof, obtained from a wind tunnel test for a low-rise building with a gable roof, using the analytical method.

The purpose of this paper is to understand elasto-plastic wind response characteristics of detached timber buildings with visco-elastic dampers that began to spread recently. The following approach is employed in this study. 1) Loading experiments acting long-duration random waves such as wind forces on a timber-frame wall with the dampers are conducted to examine their dynamic behavior. 2) Accuracy of time history behavior analysis of the wall is verified by comparing their results with the experiment results. 3) Time history wind response analyses with single degree of freedom models of the buildings are carried out to examine their characteristics. Furthermore, elastic response analyses and earthquake response analyses are carried out, then the wind response characteristics are set out by comparing each other.

For the synthesis of protopine alkaloids, we studied a reaction sequence based on a ring enlargement of indeno[2,1-a][3]benzazepines by a singlet oxygen oxygenation, followed by conversion of an amide carbonyl group of the resultant 10-membered keto-lactam to a methylene group, which is the last step for completion of the synthesis. The key substances, indeno[2,1-a][3]benzazepines, were prepared by Bischler-Napieralski cyclization of alkoxy-substituted 1-(2-bromobenzyl)-3-benzazepin-2-ones. Steric effects of the substituents in this synthesis were examined.

Asymmetric hydrogenation of ketones catalyzed by XylBINAP/chiral diamine-Ru (II), To1BI-NAP/PICA-Ru (II), η6-arene/TsDPEN-Ru (II), and MsDPEN-CpIr (III) complexes affords a variety of sec-ondary alcohols with high enantioselectivity. Complete conversion is attainable with a low catalyst loading. The high catalyst efficiency is rationalized by a novel “metal-ligand cooperative mechanism.”

Wind response characteristics of a five-storied pagoda were clarified in this study. The wind response analysis was carried out using wind forces obtained from wind tunnel tests with a scaled model of five-storied pagoda and an elasto-plastic structural model of the five-storied pagoda considered with non-linear structural system of traditional wooden members.