Reaction of phenyl-containing N-substituted 1,3-oxazolidines and 1,3-oxazinanes with triammine(tricarbonyl)chromium

Russian Chemical Bulletin - New heterocyclic compounds with phenyl chromium tricarbonyl substituents were synthesized by the reaction of triammine(tricarbonyl)chromium with phenyl-substituted...     

Synthesis of New Bulky Bis(amidine) with the Conformationally Rigid meta-Phenylene Bridge and Its Dilithium Derivative [1,3-C6H4{NC(Ph)N(2,6-iso-Pr2C6H3)}2]Li2(TMEDA)2

Russian Journal of Coordination Chemistry - The reaction of 2,6-diisopropylaniline with m-phenylenedibenzimidoyl chloride 1,3-C6H4{N=C(Ph)Cl}2 in the presence of triethylamine in a toluene solution...     

Reactions of alkali metal diphenylmethanides [(3,5-Bu2t-2-MeO-C6H2)2CH]M (M = Li,K) with LnCl3. The synthesis and structure of the complex [(3,5-Bu2t-2-MeO-C6H2)2CH]2ScCl

Russian Chemical Bulletin - The outcome of the exchange reactions of alkali metal diphenylmethanides [(3,5-Bu2t-MeO-C6H2)2CH]M (M = Li (2), K (3)) with LnCl3 is determined by the nature of the...     

Application of the Molecular Invariom Model for the Study of Interactions Involving Fluorine Atoms in the { $${\text{Yb}}_{{\text{2}}}^{{{\text{II}}}}$$ (μ2-OCH(CF3)2)3(μ3-OCH(CF3)2)2YbIII(OCH(CF3)2)2(THF)(Et2O)} Complex

Russian Journal of Coordination Chemistry - The electron density distributions obtained by the quantum-chemical (density functional theory) calculations and molecular invariom model in the trimeric...     

Triphenylantimony(V) Catecholates of the Type (3-RS-4,6-DBCat)SbPh3-Catechol Thioether Derivatives: Structure,Electrochemical Properties,and Antiradical Activity

A new series of triphenylantimony(V) 3-alkylthio/arylthio-substituted 4,6-di-tert-butylcatecholates of the type (3-RS-4,6-DBCat)SbPh₃, where R = n-butyl (1), n-hexyl (2), n-octyl (3), cyclopentyl (4), cyclohexyl (5), benzyl (6), phenyl (7), and naphthyl-2 (8), were synthesized from the corresponding catechol thioethers and Ph₃SbBr₂ in the presence of a base. The crystal structures of 1, 2, 3, and 5 were determined by single-crystal X-ray analysis. The coordination polyhedron of 1–3 is better described as a tetragonal pyramid with a different degree of distortion, while that for 5- was a distorted trigonal bipyramid (τ = 0.014, 0.177, 0.26, 0.56, respectively). Complexes demonstrated different crystal packing of molecules. The electrochemical oxidation of the complexes involved the catecholate group as well as the thioether linker. The introduction of a thioether fragment into the aromatic ring of catechol ligand led to a shift in the potential of the “catechol/o-semiquinone” redox transition to the anodic region, which indicated the electron-withdrawing nature of the RS group. The radical scavenging activity of the complexes was determined in the reaction with DPPH radical.     

Sterically Hindered o‐Quinone Annulated with Dithiete: A Molecule Comprising Diolate and Dithiolate Coordination Sites

A new stable sterically hindered o‐quinone annelated with a 1,2‐dithiete ring was prepared by using mild conditions. The skeleton of the compound comprises diolate and dithiolate functions that have the potential to bind metals leading to the corresponding complexes. The reactivity of this compound as a ligand with respect to both coordination sites was studied. Reactions with metals indicate that the o‐quinone function is reduced in the first stage to give semiquinonate and catecholate complexes. The dithiolate coordination site was involved in the reaction in a few cases only after diolate was bound. A trinuclear manganese complex with coordination on both sites was obtained and characterized by EPR spectroscopy. The electrochemical study of this quinone fused with dithiete is reported.     

New potentially tridentate amidinate ligand {o-MeOC6H4NC(Ph)N(SiMe3)}?. Synthesis and molecular structures of amidinate complexes of lithium [{o-MeOC6H4NC(Ph)N(SiMe3)}Li]2 and yttrium [{o-MeOC6H4NC(Ph)N(SiMe3)}YCl2(THF)2]2

The reaction of lithium silylamide [??o-MeOC₆H₄N(SiMe₃)}Li(OEt₂)]₂ with 2 equiv. of benzonitrile in THF at ??20 °C affords the lithium derivative of the new tridentate amidinate ligand [{o-MeOC₆H₄NC(Ph)N(SiMe₃)}Li]₂. The X-ray diffraction study showed that this complex has a dimeric structure due to the coordination of the N atoms and the ether group of one amidinate ligand to different Li atoms. The reaction of anhydrous YCl₃ with the resulting complex in THF gives the monoamidinate complex [{o-MeOC₆H₄NC(Ph)N(SiMe₃)}YCl₂(THF)₂]₂ regardless of the reagent ratio. The latter has a dimeric structure in the crystalline state as a result of the presence of two ??₂-bridging Cl atoms that link Y atoms. The ether groups of the amidinate ligands are not involved in the metal-ligand interaction.     

Alkoxylation of 3,6-di-<Emphasis Type="Italic">tert</Emphasis>-butyl-1,2-benzoquinone. New bis-1,2-benzoquinones

Alkoxylation of 3,6-di-tert-butyl-1,2-benzoquinone with a number of diols, including propane-1,3-diol, butane-1,4-diol, di-, and triethylene glycols, and cyclohexane-1,4-diyldimethanol, was studied. Nine new 4-alkoxy-3,6-di-tert-butyl-1,2-benzoquinones were synthesized, four of which were bis-1,2-benzoquinones with different tethers (6–13 atoms) between the quinone fragments. Depending on the length of the chain between the hydroxy groups in glycols, bicyclic 4,5-disubstituted 3,6-di-tert-butyl-1,2-benzoquinones were formed or their stepwise alkoxylation occurred. The newly synthesized o-benzoquinone derivatives can be reduced with alkali metals to give radical anions and converted into semiquinone chelates with manganese carbonyl.     

Superelectrophilic activation of N-aryl amides of 3-arylpropynoic acids: synthesis of quinolin-2(1H)-one derivatives

The superelectrophilic activation of N-aryl amides of 3-arylpropynoic acids by Bronsted superacids (CF₃SO₃H, HSO₃F) or strong Lewis acids AlX₃ (X=Cl, Br) results in the formation of 4-aryl quinolin-2(1H)-ones in quantitative yields. The vinyl triflates or vinyl chlorides may be formed as additional reaction products. The investigated amides in reactions with benzene give 4,4-diaryl 3,4-dihydroquinolin-2-(1H)-ones under the superelectrophilic activation. 4-Aryl quinolin-2(1H)-ones in POCl₃ are converted into 4-aryl 2-chloroquinolines. 4-Fluorophenyl-4-phenyl 3,4-dihydroquinolin-2-(1H)-one give N-formylation products in a yield of 79% under the Vilsmeier–Haack reaction conditions.