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Oxidative-reductive transmetallation reactions have been classified and it has been demonstrated that the probability of their occurrence as well as the ionic versus covalent nature of their mechanism is determined by the oxidation and reduction properties of the reacting metals, metalloids, or metal complexes, as well as by their phase states.

Hexakis(pentafluorophenyl)digermane has a high reactivity that is not inherent to hexaphenyldigermane. The Ge−Ge bond in this compound is easily cleaved by water, methanol, ethylmercury chloride, and other compounds. The reactions proceed in either THF or acetone medium and fail to take place in nonpolar solvents.

1. A series of hydride complexes of nickel, palladium, and platinum was obtained by oxidative-addition reactions of zerovalent triphenylphosphine complexes of the metals with pentafluorophenyl-substituted germanes. The Pt-H groups in the obtained compounds were distinguished by low reactivity. 2. A stable complex with a Pt-Ge-Ge-Hg chain was synthesized by the reaction of HPt(PPh3)2-Ge(C6F5)2-Ge(C6F5)2H with diethylmercury.

The transmetallation of [(C6F5)3Ge]2Hg with metallic praseodymium, neodymium, and holmium yielded complexes [(C6F5)3Ge]7Hg2Ln·3DME (DME is dimethoxyethane), for which the ionic structure {[(C6F5)3Ge]7Hg2}3−Ln3+·3DME was proposed on the basis of electrical conductivity and chemical properties.

1. Bis(triethylsilyl) selenide, bis(triethylsilyl) telluride, and their germanium analogs, react with mercury salts, HgX2 (X=Cl, CN), forming the mercury chalcogenide and the compound (C2H5)3MX (M=Si, Ge). 2. The reaction of [(C2H5)3Si]2Se with ethylmercury chloride gives triethylchlorosilane and bis(ethylmercury) selenide. 3. By reacting hydrochalcogenides of the series (C2H5)3SiXH (X=S, Se, Te) with bis(triethylgermyl)-mercury, using either a 1∶1 or a 1∶2 ratio, were respectively synthesized derivatives of the type (C2H5)3Si-XHgGe(C2H5)3 and [(C2H5)3SiX]2Hg.

The reaction of triethylaluminum with compounds of the (C2H5)3SiXH series (X=S, Se, Te) proceeds with a stepwise replacement of the ethyl groups by (C2H5)3SiX moieties. Depending on the ratio of the reactants, it is possible to obtain either the monosubstitution products (C2H5)3SiXAl(C2H5)2, or the disubstitution products [(C2H5)3SiX]2AlC2H5. The disproportionation reactions of these products were investigated.

The treatment of Cp2Yb, Cp3Sm, CeCl3, Cp3Ce, and Cp3Eu·THF with excess naphthalenesodium in THF gives systems capable of reducing molecular nitrogen at 20°C and atmospheric pressure with the formation of ammonia after hydrolysis.

1. The reaction of R3GeBr (R=Et and Ph) with Sm and Ph gives Grignard-type reagents, R3GeLnBr. 2. The reaction of R3GeLnBr complexes with PhOH, EtBr, PhBr, Et3GeBr and (C6F5)3GeBr give Et3GeH, Et4Ge, Ph4Ge, Et4Ge2 and Et3GeGe(C6F5)3, respectively.

Several complexes of bis[tri(pentafluorophenyl)germyl]eadmium with ligands of the donor type were synthesized.

1. The reaction of triethylsilylselenium hydride with triethylaluminum takes place with the formation of ethane and of heteroorganic compounds with an Si-Se-Al grouping as intermediate or final products. 2. The composition of the reaction products is determined by the ratio of the reactants and the temperature conditions.

Depending on the ratio of the reactants, the reaction of triethylsilylhydroselenide with diethylzinc and diethylcadmium proceeds with the formation of the mono- and disubstituted products of the series [(C2H5)3SiSe]nM(C2H5)2-n, where M=Zn, Cd; n=1 or 2, which were isolated as the crystalline associates.

1. It was shown that bis(triethylsilyl) sulfide and its isologs can be separated and studied by the GLC method. 2. The values of the specific retained volumes and the differential heats of solution (QS) of these compounds in a nonpolar solvent, and specifically in Apiezon L, were determined. It was found that QS is linearly dependent on the molecular weight of the compounds.

The authors have established that metallic uranium reacts with ((C/sub 6/F/sub 5/)/sub 3/Ge)/sub 3/Hg at about 20/sup 0/C in a medium of 1,2-dimethoxyethane (DME). The reaction was complete after 3 h by the separation of metallic mercury (100 %) and by the formation of the heptakis (tris(pentafluoro-phenyl)germyl) dimercurate of uranium (((C/sub 6/F/sub 5/)/sub 3/Ge)/sub 7/Hg/sub 2/)U3DME (i), 81%. 1 reference.