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31.
Saito K Sogou H Suga T Kusama H Iwasawa N 《Journal of the American Chemical Society》2011,133(4):689-691
Pt(II)-catalyzed generation of unsaturated carbene complex intermediates from various propargyl ether derivatives based on electrophilic activation of alkynes was realized. These in situ generated unsaturated carbene complexes undergo [3+2] cycloaddition reaction with various vinyl ethers, leading to efficient formation of indoles, naphthols, and benzofuran fused with a five-membered ring in high yields. 相似文献
32.
Ito K Tamashima H Iwasawa N Kusama H 《Journal of the American Chemical Society》2011,133(11):3716-3719
Intermolecular carbon-carbon bond formation between acylsilanes and organoboronic esters was achieved by photoirradiation under almost neutral, transition metal-free conditions. In this reaction, siloxycarbenes generated by photoisomerization of acylsilanes reacted with boronic esters to give the formal B-C bond insertion intermediates, which underwent unique rearrangement to afford the cyclic α-alkoxyboronic esters. Acidic treatment of the resulting crude products under air furnished the cross-coupled ketones in good yields. 相似文献
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We have found a surfactant-promoted novel reductive synthesis of metallic Cu nanoclusters on metal oxides under hydrothermal synthesis conditions, which are active for the selective dehydrogenation of methanol. 相似文献
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H. Iwasawa J.F. Douglas K. Sato T. Masui Y. Yoshida Z. Sun H. Eisaki H. Bando A. Ino M. Arita K. Shimada H. Namatame M. Taniguchi S. Tajima S. Uchida T. Saitoh D.S. Dessau Y. Aiura 《Physica C: Superconductivity and its Applications》2010
Using angle-resolved photoemission spectroscopy (ARPES) with low-energy tunable photons, we studied the oxygen isotope effect in optimally doped Bi2Sr2CaCu2O8+δ (Bi2212). We found the oxygen isotope shift in the real part of the electron self-energies [ReΣ(ω)s] along the nodal direction derived not only from the momentum distribution curves (MDCs) but also from the energy distribution curves (EDCs). Present results indicate straightforwardly the coupling between the nodal electrons and the phonons. 相似文献
39.
Iwasawa H Yoshida Y Hase I Koikegami S Hayashi H Jiang J Shimada K Namatame H Taniguchi M Aiura Y 《Physical review letters》2010,105(22):226406
Using polarization- and hν-dependent angle-resolved photoemission spectroscopy, we uncovered the fine details of a quasiparticle's dynamics of a typical multiband superconductor, Sr2RuO4. We found strong hybridization between the in-plane and out-of-plane quasiparticles via the Coulomb and spin-orbit interactions. This effect enhances the quasiparticle mass due to the inflow of out-of-plane quasiparticles into the two-dimensional Fermi surface sheet, where the quasiparticles are further subjected to the multiple electron-boson interactions. We suggest that the spin-triplet p-wave superconductivity of Sr2RuO4 is phonon mediated. 相似文献
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[reaction: see text] Only 1-3 mol % of PtCl(2) or AuBr(3) was sufficient to promote generation and [3+2] cycloaddition of transition-metal-containing azomethine ylides derived from N-(o-alkynylphenyl)imines bearing an internal alkyne moiety. A highly efficient method for the preparation of synthetically useful tricyclic indole derivatives having a substituent at the 3-position of the indole nucleus was established by this method. 相似文献