The key goal of the work is elaboration of novel synthetic approach to heterometallic coordination compounds based on oxidative dissolution of zero-valent metals in the presence of a source of second metal and N,- O-donor ligands in air.
Conditions of heterometallic compounds formation in the frame of the proposed method were studied and generalized. It is shown that the the key role in probability of target compound formation played the "ligand system", namely the combination of organic compound and inorganic anion. This approach allowed obtaining the wide range of heterometallic compounds with crystal structures from polynuclear to cation-anionic depending on the nature of “ligand system”.
It was established that in the case of the use of proton-donor ligands, such as amino alcohols – diethanolamine (H2Dea) and 2-dimethylaminoethanol (HMe2ea), the "salt" method is the most suitable. The introduction into the reaction mixture of metallic copper and two salts of different metals (Co, Ni, Zn, Cd) allows to obtain heterotrimetal compounds.
For the first time in the direct synthesis to obtain heterometallic compounds based on manganese with aprotic ligands (en and phen) it was proposed to use potassium permanganate or tetrabutylammonium.
The "ammonium-salt" route was used to obtain heterometallic compounds in the presence of a ligand system "carboxylate-aprotic ligand". Acetate was chosen as one of the simplest representatives of monocarboxylates, conformationally rigid (oxalate) or flexible (malonate, succinate) anions were studied among dicarboxylates, and 2,6-pyridinedicarboxylate was chosen as a representative of heterocyclic tridentate N, O-donors.
In the presence of vanadium(V) oxide, oxidative dissolution of metals (Cu, Co, Mn) in aqueous solutions leads to the formation of hybrid compounds based on decavanadate. It is shown that in the presence of V2O5 due to "catastrophic corrosion" the dissolution time of the metal is significantly reduced.
To obtain hybrid compounds based on polyoxomolybdates with complex particles Cu, Co or Ni, a modification of direct synthesis is proposed, which consists in the interaction of zero-valent metal with starting compounds for polyoxoanion assembly in the presence of N, N-donor ligand in aqueous medium with free access of air oxygen. For the first time, hybrid compounds with a V-substituted Keggin anion [PMo12 хVхO40]n– (х = 3, n = 6; х = 4, n = 7) were obtained by self-assembly, and a high degree of substitution was achieved.
The catalytic activity of the synthesized compounds and products of their thermal decomposition was studied and it was shown that the photochemical oxidation of water for water-soluble hybrid compounds based on decavanadate and octamolybdate increased the activity in the series Cu> Mn> Co. It was found that the Cu/ZnО composite obtained by heat treatment of the compound [Cu(en)2(μ-H2O)2Zn(OAc)4]·4Н2О, showed high catalytic activity in the reaction of methanol synthesis, which increases when it is applied to the surface aerosil and exceeds the activity of the industrial catalyst at almost an order of magnitude lower copper content. High selectivity for alcohols and alkenes in the hydrogen monoxide hydrogenation reaction (Fischer-Tropsch process) was shown by a bimetallic Cu/Co sample obtained by thermal decomposition of [Cu(en)2][Co2(C2O4)3]·3H2O. Hybrid compounds with Strandberg anion and its lacunar derivative revealed high sorption capacity of cationic dye methylene blue.
