Chemical transformations of reaction products of 2-methyl-3-(4-tolyl)-4(3<Emphasis Type="Italic">H</Emphasis>)-quinazolone with benzil and its 4,4′-derivatives

The reaction of 2-methyl-3-(4-tolyl)-4(3H)-quinazolone with benzil produces 2-[(Z)-3-oxo-2,3-diphenylprop-1-enyl]-3-(4-tolyl)-4(3H)-quinazolone, which is readily transformed into 2-(3,3-diphenylsuccinimido)-N-(4-tolyl)benzamide on dissolution in organic water-containing solvents. The rearrangement mechanism was suggested and investigated by the quantum chemical PM3 method. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 146–151, January, 2007.     

Synthesis of the gold-dirhenium ferrocenylacetylide cluster. The crystal structure of Re2(μ-C≡CFc){Au(PPh3)}(CO)8

The thermal reaction of Re₂(CO)₈(NCMe)₂ with Au(CCFc)PPh₃ afforded the cluster Re₂(-CCFc){Au(PPh₃)}(CO)₈, which was characterized by X-ray diffraction analysis.     

Synthesis of dicationic triple-decker complexes with a central B-cyclohexyl-substituted borole ligand

Stacking reactions of the dicationic fragments [LM]²⁺ (LM = (-C₆H₆)Ru, (-C₆H₃Me₃)Ru, or (-C₅Me₅)Rh) with the complex (-C₅H₅)Co(-C₄H₄BCy) (Cy = cyclo-C₆H₁₁) afforded new dicationic 30-electron triple-decker complexes [(-C₅H₅)Co(-:-C₄H₄BCy)ML](BF₄)₂ containing a cyclohexyl-substituted borole ligand in the central position.     

P,N-Bidentate Phosphorus Derivatives of (S)-Prolinol

Phosphorylation of (S)-prolinol with P(NEt₂)₃was used to synthesize aminophosphite (2R,5S)- , which was reacted with the corresponding amino alcohols to afford (2S,5R)- (Va) and (2S,5R)- (Vb). Reaction of Vawith [Rh(CO)₂Cl]₂(P/Rh = 1) yields the mononuclear chelate [Rh(CO)(P^N)Cl] (VIIa), while the analogous reaction with Vbresults in a mixture of products with cis- and trans-orientation of the coordinated phosphorus and nitrogen atoms. Spectral characteristics of the products of coordination of ligands Vaand Vbwere compared with those for the binuclear reference complex [Rh(CO)(L)Cl]₂(VIII), where L is P-monodentate ligand (2S,5R)- (VI). The ligands and complexes were studied by IR, NMR, ³¹P and ¹³C spectroscopy, mass spectrometry, and elemental analysis methods. X-ray diffraction analysis of crystals VIIIwas performed.     

Synthesis of the iridacarborane halide complexes [(η-9-SMe2-7,8-C2B9H10)IrX2]2 (X = Cl,Br, or I)

The reaction of Na[9-SMe₂-7,8-C₂B₉H₁₀] with [(Cod)IrCl]₂ (Cod is cycloocta-1,5-diene) gave rise to the iridium complex (-9-SMe₂-7,8-C₂B₉H₁₀)Ir(Cod). Treatment of the latter with anhydrous acids HX (X = Cl, Br, or I) afforded the corresponding iridacarborane halide complexes [(-9-SMe₂-7,8-C₂B₉H₁₀)IrX₂]₂ analogous to the cyclopentadienyl complexes [(C₅Me₅)IrX₂]₂.     

Functionalization of one or two methyl groups in the [Cp*<Subscript>2</Subscript>RuBr]<Superscript>+</Superscript>Br<Superscript>−</Superscript> complex in the reaction with bromine

The reaction of [Cp*₂RuBr]⁺Br⁻ with bromine in CH₂Cl₂ (CD₂Cl₂) in an inert atmosphere at room temperature produces the complexes [Cp*Ru(Br)C₅Me₄CH₂Br]⁺Br₃ ⁻ (syn conformer), [Cp*Ru(Br)C₅Me₃(CH₂Br)₂]⁺ (syn and anti conformers), and [Ru(Br)(C₅Me₄CH₂Br)₂]⁺ (syn conformer). All complexes were characterized by ¹H and ¹³C NMR spectroscopy; the former complex, by elemental analysis. These complexes were also prepared by the reaction of [Cp*RuC₅Me₄CH₂]⁺BF₄ ⁻ with bromine in CH₂Cl₂. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2712–2718, December, 2005.     

Alkyne-vinylidene coupling in the reactions of the alkyne complex Os3(μ-CO)(CO)9(μ3-Me3C2Me) with Me3SiC≡CR (R=Me, Bun). The structure and stereodynamic behavior of clusters Os3(CO)9{μ3-C(SiMe3)=C(Me)C=C(SiMe3)=C(Me)C=C(SiMe3)R} containing an osmacyclobutene moietycontaining an osmacyclobutene moiety

Reactions of the alkyne cluster Os₃(μ-CO)(CO)₉(μ₃-Me₃C₂Me) with alkynes Me₃SiC≡CR (R=Me, Buⁿ) in refluxing hexane result in the formation of clusters Os₃(CO)₉{μ₃-C(SiMe₃)=C(Me)C=C(SiMe₃)=C(Me)C=C(SiMe₃)R} (2a: R=Me;3a: R=Buⁿ). The dienediyl ligand in these complexes is formed by alkyne-vinylidene coupling, with vinylidene generated in the course of reaction from the alkyne molecule by the acetylene-vinylidene rearrangement involving a 1,2-shift of the Me₃Si group. The structure of cluster3a was determined by X-ray structural analysis. The dienediyl ligand is coordinated to three metal atoms of the cluster framework by two π-ethylene bonds with two osmium atoms and two σ-bonds with the third osmium atom with the formation of the osmacyclobutene moiety. The¹H and¹³C NMR study of¹³CO-enriched samples of clusters2a and3a revealed the stereochemical nonrigidity of these molecules due to the exchange of the hydrocarbon and carbonyl ligands.     

Functionalization of alkanes and cycloalkanes by superelectrophiles. 15. Carbonylation of cycloheptane,cyclooctane, and isomeric monoalkylcyclohexanes with CO in the presence of CBr4·2AlBr3 to form individual esters of tertiary carboxylic acids of the cyclohexane series

Cycloheptane, methylcyclohexane, cyclooctane, and ethylcyclohexane were selectively carbonylated with CO. The reactions of cycloalkanes with CO at –40 °C in the presence of the superelectrophilic system CBr₄·2AlBr₃ in CH₂Br₂ followed by treatment of the reaction mixtures with alcohols afforded esters of 1-methylcyclohexanecarboxylic acid (in the reactions of cycloheptane and methylcyclohexane) or esters of 1-ethylcyclohexanecarboxylic acid (in the reactions of cyclooctane and ethylcyclohexane) in 70—80% yields with respect to CBr₄·2AlBr₃. The reaction of 1,3-dimethylcyclohexane at –40 °C and the reactions of cyclooctane and ethylcyclohexane and at –20 °C proceeded nonselectively to form four isomeric esters C₈H₁₅COOR.     

Metallocenyl cations : IV. cymantrenyl carbenium ions containing two phosphine ligands

Cymantrene carbinols (I) with two phosphine ligands (PP) have been synthesized. Carbinols I (where PP is the chelate diphosphine Ph₂PCH₂CH₂PPh₂ or Ph₂PCH₂CH₂CH₂PPh₂) form the corresponding carbenium ions (II), stabilized by manganese, in the presence of CH₃COOH. The phosphorus atosm of the chelate diphosphine ligands become non-equivalent in the carbenium ions. IR spectra and ³P and ¹³C NMR spectra have been recorded, and the nature of the non-equivalence and of the structure of cymantrenyl carbenium ions are discussed. In the presence of CF₃COOH carbinols i (where PP = 2PMe₂(C₆H₄CH₃-p or 2PPH₂Me) are protonated at the metal atom.     

Photochemical substitution of benzene in the iron cyclohexadienyl complex [(η<Superscript>5</Superscript>-C<Subscript>6</Subscript>H<Subscript>7</Subscript>)Fe(η-C<Subscript>6</Subscript>H<Subscript>6</Subscript>)]<Superscript>+</Superscript>

The visible light irradiation of the [(η⁵-C₆H₇)Fe(η-C₆H₆)]⁺ cation (1) in acetonitrile resulted in the substitution of the benzene ligand to form the labile acetonitrile species [(η⁵-C₆H₇)Fe(MeCN)₃]⁺ (2). The reaction of 1 with Bu^tNC in MeCN produced the stable isonitrile complex [(η⁵-C₆H₇)Fe(Bu^tNC)₃]⁺ (3). The photochemical reaction of cation 1 with pentaphosphaferrocene Cp*Fe(η-cyclo-P₅) afforded the triple-decker cation with the bridging pentaphospholyl ligand, [(η⁵-C₆H₇)Fe(μ-η:η-cyclo-P₅)FeCp*]⁺ (4). The latter complex was also synthesized by the reaction of cation 2 with Cp*Fe(η-cyclo-P₅). The structure of the complex [3]PF₆ was established by X-ray diffraction. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2088–2091, November, 2007.