Results 261 to 270 of about 284,604 (310)
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The chemistry of (ring)Ru2+ (ring = tetramethylthiophene, p-cymene)
Organometallics, 1991Described are the compounds ((ring)Ru(OTf){sub 2}){sub x}, where ring = 2,3,4,5-tetramethylthiophene (TMT, 1), and p-cymene (2). These electrophilic reagents serve as precursors to ((ring)RuL{sub 3}){sup 2+}, where L{sub 3} = (H{sub 2}O){sub 3}, (NH{sub 3}){sub 3}, and (PH{sub 3}){sub 3}. Solutions of 1 and 2 react with carbon monoxide to give (ring)Ru(
Edward A. Ganja +2 more
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The 1,2,3-triazole ring as a bioisostere in medicinal chemistry
Drug Discovery Today, 20171,2,3-Triazole is a well-known scaffold that has a widespread occurrence in different compounds characterized by several bioactivities, such as antimicrobial, antiviral, and antitumor effects. Moreover, the structural features of 1,2,3-triazole enable it to mimic different functional groups, justifying its wide use as a bioisostere for the synthesis of
Elisa, Bonandi +5 more
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Ring Transformations in Tetrazole Chemistry
Journal f�r Praktische Chemie/Chemiker-Zeitung, 1998Transformations of heterocycles into tetrazoles as well as conversions of the latter into other rings are reviewed. The literature is covered through early 1998 (material that has been surveyed by Van der Plas [1] and Benson [2] is resumed in abridged fashion).
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Equilibria in Organo Antimony Ring Chemistry
Phosphorus, Sulfur, and Silicon and the Related Elements, 1992Abstract Reactions of ethyl antimony and n-propyl antimony rings give equilibria with the mixed substituted derivatives R(n-m)R′mSbn (n = 4, m=1-3; n=5, m=1-4; R=Et, R′= n-Pr). The equilibrium constant K = [(EtSb)4]5/[(EtSb)5]4 has been determined as K = 9.10−8 mol/l. Air oxidation of p-TolSb(SiMeo3)2 gives yellow crystals of p-tolylantimony.
H. J. Breunig, S Gülec, R. Kaller
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Coordination Chemistry of Open-Ring Hemiporphyrazines
ECS Meeting Abstracts, 2023Hemiporphyrazines, phthalocyanine analogues consisting of two isoindoline subunits and two pyridine or other aromatic subunits, have attracted considerable interest not only from the viewpoint of their fundamental properties but also in materials science.
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Unusual ring systems in organic chemistry
Naturwissenschaften, 1977In this article several compounds with unusual ring systems are surveyed briefly. Saturated and unsaturated monocyclic compounds, polycyclic compounds, and unconventional aromatic systems are covered. The reasons for the interest of organic chemists in the unusual ring systems are discussed.
Hanack, Michael +2 more
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Ring expansion reactions in organonickel chemistry
Journal of the Chemical Society D: Chemical Communications, 1970In contrast with the reactions of NiL4(L = tertiary phosphine), Ni(ButNC)4 reacts with (CF3)2CO and (CF3)2CNH to give five-membered-ring compounds (ButNC)2[graphic omitted](X = O or NH) in an almost stereoselective 3- to 5-ring transformation.
A. Greco +3 more
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Chemistry and Prevention of PISTON-RING STICKING
SAE Technical Paper Series, 1945<div class="htmlview paragraph"><b>OXIDATION of lubricating oils produces, among other products, oxyacids, which, according to the study made by these authors, constitute the source of ring sticking because of a tendency to turn into insoluble deposits.</b></div> <div class="htmlview paragraph"><b>The chemical ...
G. H. DENISON, J. O. CLAYTON
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