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221.
Kota Thirumala Prasad Gajendra Gupta Anna Venkateswara Rao Babulal Das Kollipara Mohan Rao 《Polyhedron》2009,28(13):2649-2654
The mononuclear complexes [(η6-arene)Ru(ata)Cl]PF6 {ata = 2-acetylthiazole azine; arene = C6H6 [(1)PF6]; p-iPrC6H4Me [(2)PF6]; C6Me6 [(3)PF6]}, [(η5-C5Me5)M(ata)]PF6 {M = Rh [(4)PF6]; Ir [(5)PF6]} and [(η5-Cp)Ru(PPh3)2Cl] {η5-Cp = η5-C5H5 [(6)PF6]; η5-C5Me5 (Cp*) [(7)PF6]; η5-C9H7 (indenyl); [(8)PF6]} have been synthesised from the reaction of 2-acetylthiazole azine (ata) and the corresponding dimers [(η6-arene)Ru(μ-Cl)Cl]2, [(η5-C5Me5)M(μ-Cl)Cl]2, and [(η5-Cp)Ru(PPh3)2Cl], respectively. In addition to these complexes a hydrolysed product (9)PF6, was isolated from complex (4)PF6 in the process of crystallization. All these complexes are isolated as hexafluorophosphate salts and characterized by IR, NMR, mass spectrometry and UV–Vis spectroscopy. The molecular structures of [2]PF6 and [9]PF6 have been established by single-crystal X-ray structure analyses. 相似文献
222.
Observation of a Metastable P‐Heterocyclic Radical by Muonium Addition to a 1,3‐Diphosphacyclobutane‐2,4‐diyl 下载免费PDF全文
Prof. Dr. Shigekazu Ito Dr. Yasuhiro Ueta Kota Koshino Prof. Dr. Kenji M. Kojima Dr. Iain McKenzie Prof. Dr. Koichi Mikami 《Angewandte Chemie (International ed. in English)》2018,57(28):8608-8613
A 1,3‐diphosphacyclobutane‐2,4‐diyl contains a unique unsaturated cyclic unit, and the presence of radical‐type centers have been expected as a source of functionality. This study demonstrates that the P‐heterocyclic singlet biradical captures muonium (Mu=[μ+e?]), the light isotope of a hydrogen radical, to generate an observable P‐heterocyclic paramagnetic species. Investigation of a powder sample of 2,4‐bis(2,4,6‐tri‐t‐butylphenyl)‐1‐t‐butyl‐3‐benzyl‐1,3‐diphosphacyclobutane‐2,4‐diyl using muon (avoided) level‐crossing resonance (μLCR) spectroscopy revealed that muonium adds to the cyclic P2C2 unit. The muon hyperfine coupling constant (Aμ) indicated that the phosphorus atom bearing the t‐butyl group trapped muonium to provide a metastable P‐heterocyclic radical involving the ylidic MuP(<)=C moiety. The observed regioselective muonium addition correlates the canonical formula of 1,3‐diphosphacyclobutane‐2,4‐diyl. 相似文献
223.
Dr. Yuichi Kitagawa Ayu Naito Kota Aikawa Kaori Shima Dr. Sunao Shoji Dr. Koji Fushimi Prof. Yasuchika Hasegawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(16):e202104401
A spin-selective tribo-chemical reaction using a dinuclear lanthanide complex is demonstrated for the first time. The dinuclear complex is composed of two EuIII ions, hexafluoroacetylacetonato ligands, and anthracene-based phosphine oxide bridges. Single-crystal analysis revealed a face-to-face-type anthracene dimer structure in the dinuclear EuIII complex. Mechanical stimulus on the dinuclear EuIII complex induced selective formation of oxidized anthracene. The tribo-chemical reaction is based on a characteristic energy-transfer pathway for the selective formation of an excited triplet state. 相似文献
224.
Kota Yamamoto Dr. Enol López Dr. Pablo Barrio Dr. Javier Borge Prof. Luis A. López 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(31):6999-7003
Gold-catalysis has enabled new synthetic opportunities in the chemistry of vinyldiazo compounds. Herein, we report the gold-catalyzed reaction of stabilized vinyldiazo compounds with pinacol alkenylboronates to provide boryl-functionalized cyclopentene derivatives through a formal [3+2] carbocycloaddition reaction, a very unusual pathway in alkenylboronate chemistry. This reaction proceeds with high regio- and stereoselectivity. The synthetic usefulness of the resulting borylated cyclopentene derivatives toward the synthesis of densely functionalized cyclopentanoids is also demonstrated. 相似文献