N. A. Ovchinnikova

Insertion of Ethyl Isocyanate at the Tungsten–Chlorine Bond. Crystal Structure of 1,3,5-Triethyl-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione

The reaction of tungsten hexachloride with excess ethyl isocyanate in dichloroethane leads to the insertion of three ligand molecules at one of the tungsten–chlorine bonds. The data of elemental analysis and IR spectroscopy confirm that the thermolysis of the reaction mixture affords the WCl4(L3Cl) complex (I), where L = –N(Et)C(O)–. The structure of the chain of inserted molecules in I is established on the basis of IR and NMR data, and the results of X-ray diffraction analysis of crystals of an organic product (II) of the hydrolysis of I. According to the latter, compound (II) is a derivative of s-triazine—1,3,5-triethyl-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione.

Heteromolecular insertion of EtNCX (X = O, S) and RCN (R = CH3, C6H5) into tungsten hexachloride

The interactions of tungsten hexachloride with EtNCX (X = O, S) and RCN (R = CH3, C6H5) were studied. In the case of E = CH3, heterocumulenes are inserted at the W-Cl bond, while in the case of R = C6H5, they were inserted at a multiple tungsten-nitrogen bond of an intermediate imido complex [WCl4(NCPh)(CNCl2Ph)]. The IR, MALDI TOFF mass spectroscopy, and elemental analysis data confirmed that these interactions yielded the products of heteromolecular insertion, namely, [WCl4{(EtNCO)2(MeCN)Cl}], [WCl4(EtNCS)2(MeCN)Cl], [WCl4N(CCl2Ph)C(=NEt)O}], and WCl4N(CCl2Ph)C(=NEt)S}], whose compositions and structures were determined by the nature of the organic nitrile radical.

Effect of the properties of the water sorbent on the heat generation in the Fe-C-NaCl-H2O-O2 system

The water adsorption and retention behaviors of vermiculite, silica gel, activated carbon, and a zeolite are analyzed in relation to their pore structures, and their effects on the dynamics of heat generation in Fe-C-NaCl-H2O-O2-water sorbent systems are investigated.

Regioselectivity of the insertion of RNSO(S) and RCN into the M–L bonds of the tungsten chlorocomplexes

The results of studying the reaction behavior of tungsten hexachloride toward organic iso(thio)cyanates and their combinations with nitriles are generalized. The factors determining the multiplet insertion of iso(thio)cyanates at the W–Cl bond and the conditions of symmetrical or asymmetrical crosslinking of the inserted fragments into heterocycles upon their trimerization (on the basis of the X-ray structural data on the products of the partial or complete hydrolysis of the complexes) are discussed. The reasons determining the direction of the combined insertion of heterocumulenes and nitriles at the W–Cl or W–N bond are considered, which is important for the targeted design of complexes of various architecture and new poorly accessible related heterocyclic compounds.

Synthesis of 4-ethyl-5-ethylimino-[1,2,4]-dithiazolidin-3-trithione through ethyl-(4-ethyl-5-thioxo-[1,2,4]-dithiazolidin-3-ylidene)ammonium oxopentachlorotungstate(VI) hydrolysis and the dimroth rearrangement in it on heating

We demonstrate that the previously synthesized product of ethyl isothiocyanate insertion into tungsten hexachloride, WCl5{N(Et)C(S)N(Et)C(S)Cl}, whose partial hydrolysis yields {N(Et)C(S)-S-S-C=NH(Et)}[WOCl5] (I), can be used as a source of biologically active heterocyclic compounds. 1H and 13C NMR and gas chromatography-mass spectrometry data show that reaction of I with a saturated aqueous Na2CO3 solution yields a number of thiazolidine heterocycles, mostly 4-ethyl-5-ethylimino-[1,2,4]-dithiazolidin-3-trithione. The thermal Dimroth rearrangement leads to the formation of 2,4-diethyl-[1,2,4]-dithiazolidin-3,5-dithione and the products of partial hydrolysis of both heterocycles: 4-ethyl-5-ethylimino-[1,2,4]-dithiazolidin-3-on and 2,4-diethyl-3-thioxo-[1,2,4]-dithiazolidin-5-on.

Synthesis of carboxylate derivatives of molybdenum and tungsten based on joint insertion of CO2 and PhNCS or N, N′-dicyclohexylcarbodiimide into M-Cl bonds

Reactions of the higher molybdenum and tungsten chlorides with phenyl isothiocyanate or with N, N′-dicyclohexylcarbodiimide and carbon dioxide in dichloroethane are the first to demonstrate the possibility of insertion of carbon dioxide in combination with other heterocumulenes into transition metal-halogen bonds. IR spectroscopy and elemental analysis data show that the reactions result in the attachment of the ligands at the same metal-chlorine bond and the formation of heteromolecular insertion products with the compositions

Complex Formation During Molybdenum Chlorination in DMF Medium

\left[ {MoOCl_3 \left\{ {N\left( {Ph} \right)C\left( S \right)} \right\}_2 Nc\left( {Me} \right)Cl} \right]

Composition and Structure of [WCl4{N(Et)C(O)}3Cl]: MALDI-TOF Mass Spectrometric Study

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