We investigated the electronic structure of monolayer VTe2 grown on bilayer graphene by angleresolved photoemission spectroscopy (ARPES). We found that monolayer VTe2 takes the octahedral 1T structure in contrast to the monoclinic one in the bulk, as evidenced by the good agreement in the Fermi-surface topology between ARPES results and first-principles band calculations for octahedral monolayer 1T -VTe2. We have revealed that monolayer 1T -VTe2 at low temperature is characterized by a metallic state whereas the nesting condition is better than that of isostructural monolayer VSe2 which undergoes a CDW transition to insulator at low temperature. The present result suggests an importance of Fermi-surface topology for characterizing the CDW properties of monolayer TMDs.Layered transition-metal dichalcogenides (TMDs) are a promising candidate for realizing outstanding properties associated with two-dimensionalization since bulk TMDs are known to exhibit various physical properties such as magnetism, Mott-insulator phase, and charge density wave (CDW), besides the wide range of transport property (insulator, semiconductor, metal, and superconductor), most of which are prone to the change in the dimensionality of materials. When TMDs are thinned to a single monolayer (2D limit), they exhibit even more outstanding properties distinct from bulk, as represented by the room-temperature ferromagnetism in VSe 2 in contrast to the nonmagnetic nature of bulk [1] and the change in the band-gap property from indirect to direct transition in MoS 2 [2]. The CDW is a most pronounced phenomenon widely seen in both bulk and atomic-layer TMDs. In bulk TMDs, the interplay between the Fermisurface nesting and the energy-gap opening as well as its relationship to the strength of CDW properties such as the CDW transition temperature (T CDW ) has been a target of intensive studies [3].The role of dimensionality to the mechanism of CDW, in particular whether or not the CDW is more stable in the 2D limit, is now becoming a target of fierce debates, being stimulated by a recent success in fabricating various atomic-layer TMDs by exfoliation and epitaxial techniques. Recent studies on some TMDs such as TiSe 2 , VSe 2 , and NbSe 2 [4-8] have shown a marked increase in T CDW upon reducing the thickness down to a few monolayers. In contrast, it has been reported that the CDW vanishes in monolayer TaS 2 and TaSe 2 [9, 10], suggesting an important role of substrate and many-body effects. In 1T -VSe 2 , reducing the number of layers by exfoliating bulk crystal leads at first to gradual decrease of T CDW , but at a critical film thickness of ∼ 10 nm, the T CDW exhibits a characteristic upturn and reaches 140 K in a few monolayers, much higher than bulk T CDW (110 K) [11]. Such enhancement of T CDW in monolayer VSe 2 was also revealed by angle-resolved photoemission spectroscopy (ARPES) wherein the role of FS nesting and electronphonon coupling was intensively debated [4,6,7,[12][13][14]. However, the nature of 2D CDW is still far from reaching a con...

Catalysts that can promote acyl transfer processes are important to enantioselective synthesis and their development has received significant attention in recent years. Despite noteworthy advances, discovery of small-molecule catalysts that are robust, efficient, recyclable and promote reactions with high enantioselectivity can be easily and cost-effectively prepared in significant quantities (that is, >10 g) has remained elusive. Here, we demonstrate that by attaching a binaphthyl moiety, appropriately modified to establish H-bonding interactions within the key intermediates in the catalytic cycle, and a 4-aminopyridyl unit, exceptionally efficient organic molecules can be prepared that facilitate enantioselective acyl transfer reactions. As little as 0.5 mol% of a member of the new catalyst class is sufficient to generate acyl-substituted all-carbon quaternary stereogenic centres in quantitative yield and in up to 98:2 enantiomeric ratio (er) in 5 h. Kinetic resolution or desymmetrization of 1,2-diol can be performed with high efficiency and enantioselectivity as well.

Chiral N,N-4-(dimethylamino)pyridine (DMAP) derivatives, which can be readily prepared by the Ugi multicomponent reaction in a one-pot manner, have been efficiently applied to the enantioselective Steglich rearrangement of oxindole derivatives to give the desired products bearing a quaternary carbon center in high yield (>98% yield) and with high enantioselectivity (up to 99:1 er).

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48) "Enantioselective acyl transfer catalysis by a combination of common catalytic motifs and electrostatic interactions" (47) "Facile Synthesis of 1,4-Bis(diaryl)-1,3-butadiynes Bearing Two Amino Moieties by Electrochemical Reaction Site Switching, and Their Solvatochromic Fluorescence" Kamimoto, N.; Nakamura, N.; Tsutsumi, A.; Mandai, H.; Mitsudo, K.; Wakamiya, A.; Murata, Y.; Hasegawa, J.; Suga, S Asian J. Selected as an Inside Cover (46) "Bacteriogenic iron oxide as an effective catalyst for Baeyer-Villiger oxidation with molecular oxygen and benzaldehyde" Mandai, K.; Hanata, M.; Mitsudo, K.; Mandai, H.; Suga, S.; Hashimoto, H.; Takada, J. Tetrahedron 2015, 71, 9403-9407. (45) "Synthesis and Properties of Ethene-Bridged Terthiophenes" Mitsudo, K.; Sato, H.; Yamasaki, A.; Kamimoto, N.; Goto, J.; Mandai, H.; Suga, S.