Reaction of ferrocenium ion with secondary phosphines: replacement of cyclopentadienyl ligand rather than its C—H functionalization

Russian Chemical Bulletin - The reactions of ferrocenium salts with secondary phosphines Ph2PH, Cy2PH, and Et2PH proceed as replacement of the cyclopentadienyl ring to afford half-sandwich...     

Synthesis of cationic allyl complexes from trinuclear carbonyl clusters of iron,ruthenium and osmium

Thermal and photochemical reactions of trinuclear carbonyls of Fe, Ru, Os with allyl alcohol in acidic meclium as well as their reactions with (CH₃)₃NO · 2H₂O with subsequent protonation have been studied. Cationic mononuclear allyltetra-carbonyl complexes of Fe, Ru, Os and a cationic Os cluster with π-allyl ligand, have been obtained.     

Synthesis of areneacetylenic chelate complexes of chromium with a terminal triple bond, their reversible rearrangements to areneallenic chelates, and addition at the triple bond

New areneacetylenedicarbonylchromium chelate complexes containing the terminal acetylene fragment in the side chain of the arene ligand were synthesized. The rearrangement of these chelates to the previously unknown areneallenedicarbonylchromium chelate complexes was found and studied. It was demonstrated that this rearrangement is in principle reversible. For areneallenedicarbonylchromium chelates, a new example of metallotropic rearrangement was found and both isomers, namely, with the coordination either at the substituted or at the nonsubstituted double bond of the allene ligand, were detected for the first time. The coupled addition of the proton and the nucleophile at the coordinated triple bond afforded the corresponding areneolefin chelates. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1168–1175, June, 1999.     

Mechanical tests of the conduit tubes of a conductor for the Toroidal winding of the International Thermonuclear Experimental Reactor (ITER)

Extremely stringent requirements, which include the impact toughness at the liquid-helium temperature, are imposed on the material of the conduit tubes for International Thermonuclear Experimental Reactor (ITER) Toroidal Field (TF) conductors. Modified 316LN-IG stainless steel is recommended as the conduit tube material. Steel 316LN-IG tube samples (both full-size samples and sub-sized samples) are subjected to mechanical tests at various stages of the process of conductor production: in the as-recieved state and after compacting, preliminary elongation by 2.5% at room temperature, and annealing at 650°C for 200 h in a pure helium gas atmosphere. The tests are carried out at room, liquid nitrogen, and liquid helium temperatures and satisfy the standards of the American Society of Mechanical Engineers (ASME and ASTM). The results of sub-size and full-size samples testing show that the last one gives more representative results to qualify the weld joints in liquid nitrogen. When the temperature decreases or the strain increases, the magnetization of the samples increases, especially in the weld area. Strain measurements with an extensometer demonstrate that the intracrystal processes occurring at the liquid-helium temperature can lead to a significant change in the local load, up to complete unloading in a deformation zone. Unusual local serrated deformation is observed with an extensometer installed in the weld area during tests in liquid helium: this deformation is the result of compressive jumps opposite to the loading direction.     

A new property of geminal bishydroperoxides: Hydrolysis with the removal of hydroperoxide groups to form a ketone

A new property of geminal bishydroperoxide was discovered: the ability to hydrolyze in acid medium in the presence of hydrogen peroxide with the formation of ketones. The most resistant to hydrolysis are the cyclic C₆-bishydroperoxydes: at room temperature within one day they are practically not hydrolyzed; less stable is bishydroperoxycycloheptane (C₇): in a day its one fifth part is hydrolyzed. Bishydroperoxydes with the cycles of C₈ and C₁₂ for the same time hydrolyzed to 80 and 90% respectively. Of the two linear bishydroperoxydes, 2,2-dihydroperoxydecane, with sterically unhindered center, is more resistant to hydrolysis than 6,6-dihydroperoxyundecane.