Equivariant Comparison of Quantum Homogeneous Spaces

We consider the quantum homogeneous spaces of the q-deformation of simply connected simple compact Lie groups and their Poisson–Lie quantum subgroups. We prove the deformation invariance in the equivariant KK-theory with respect to the translation action by maximal tori. This extends a result of Neshveyev and Tuset to the equivariant setting. As applications, we prove the ring isomorphism of the K-homology of G _q with respect to the coproduct of C(G _q ), and an analogue of the Borsuk–Ulam theorem for quantum spheres.     

Theoretical studies on [2 + 2 + 2] reaction mechanisms of three ethynes. More accurate estimation of activation energy

The mechanisms of the [2 + 2 + 2] cycloaddition reaction of three ethyne molecules were studied by ab initio molecular orbital and density functional methods. The transition states range from that of the concerted mechanism with D_3h symmetry to that of the stepwise mechanism with C₂ symmetry. The transition state structure and the activation energy depend on the basis set and computational method employed in the analysis. The activation energy barrier was determined to be in the range of 36–44 kcal/mol. The activation energy determined by various methods corresponds to the interaction energy, which is related to the electron correlation energy. The best estimation of the activation energy barrier is 41.6 kcal/mol, achieved from the relation between the interaction energy and the activation energy. Copyright © 2013 John Wiley & Sons, Ltd.     

Generation and Reaction of Functional Alkyllithiums by Using Microreactors and Their Application to Heterotelechelic Polymer Synthesis

Flow microreactors enabled the successful generation of various functional alkyllithiums containing electrophilic functional groups, as well as the use of these alkyllithiums in subsequent reactions. The high reactivity of these series of reactions could be achieved by the extremely accurate and selective control of residence time. Moreover, integrated flow microreactor systems could be used to successfully synthesize heterotelechelic polymers with two functionalities, one at each end, via a process involving controlled anionic polymerization initiated by functional alkyllithium compounds, followed by trapping reactions with difunctional electrophiles.     

Color representation method using RGB color binary-weighted computer-generated holograms

We propose a method for color electroholography using a simple red–green–blue(RGB) gradation representation method without controlling the respective brightness of the reference RGB-colored lights. The proposed method uses RGB multiple bit planes comprising RGB binary-weighted computer-generated holograms with various light transmittances. The object points of a given three-dimensional(3D) object are assigned to RGB multiple bit planes according to their RGB gradation levels. The RGB multiple bit planes are sequentially displayed in a time-division-multiplexed manner. Consequently, the proposed method yields a color gradation representation of a reconstructed 3D object.     

Range Corrections to Universal Tetramer Properties

The universal properties of weakly-bound tetramers close to the scaling limit are investigated by solving a subtracted set of Faddeev–Yakubovsky (FY) equations for identical bosons with a zero-range interaction. The solution demands a four-body scale independent of the trimer properties. Furthermore, the effect of a finite effective range is introduced in the FY equations, which we show produces results that are distinct from the scale variation. In particular range effects to two universal scaling functions for the tetramers are investigated. The correlation between successive tetramer energies corresponding to states within two Efimov trimer energies, proposed before and studied close to the unitary limit; and the correlation between the position of the four-atom recombination peaks. In this case, we found a shift in the scaling function due to the range, which can be associated to the shift of the data found for caesium atoms, with respect to zero-range calculations, due to a nonvanishing range in the actual experimental setups.     

Facile Redox-Induced Aromatic–Antiaromatic Interconversion of a β-Tetracyano-21,23-Dithiaporphyrin under Ambient Conditions

Facile redox-induced aromatic–antiaromatic interconversions were accomplished by using β-tetracyano-21,23-dithiaporphyrin (CN₄S₂Por). Introduced cyano groups not only increased the reduction potential of the porphyrin core but also stabilized the antiaromatic isophlorin (CN₄S₂Iph) by π conjugation. The reduction of CN₄S₂Por with hydrazine in polar solvents quantitatively affords CN₄S₂Iph, even under ambient conditions. CN₄S₂Iph retains a nearly planar conformation and exhibits considerable antiaromaticity. Aerobic oxidation of CN₄S₂Iph to CN₄S₂Por occurs in nonpolar solvents. This study was conducted to contribute to the understanding of the structure–antiaromaticity relationship.     

Practical Route to the Left Wing of CTX1B and Total Syntheses of CTX1B and 54‐deoxyCTX1B

Ciguatoxins, the principal causative agents of ciguatera seafood poisoning, are extremely large polycyclic ethers. We report herein a reliable route for constructing the left wing of CTX1B, which possesses the acid/base/oxidant‐sensitive bisallylic ether moiety, by a 6‐exo radical cyclization/ring‐closing metathesis strategy. This new route enabled us to achieve the second‐generation total synthesis of CTX1B and the first synthesis of 54‐deoxyCTX1B.