Crystal and molecular structure of 2-(p-ethoxybenzylidene)-3-phenyl-5-ethoxycarbonyl-1,3,4-selenadiazoline

Leningrad Technological Institute and Institute of Heteroorganic Compounds. Translated from Zhurnal Strukturnoi Khimii, Vol. 33, No. 5, pp. 147–149, September–October, 1992.     

Formation of π-Allyl Palladium Complexes from Tertiary Alcohols

Reactions of 2-methyl-2-propanol, 2-methyl-2-butanol, 2-methyl-2-pentanol, 1-methyl-1-cyclohexanol, and 1-ethyl-1-cyclohexanol with palladium(II) tetraaqua complex in a perchloric acid medium give carbonyl and aromatic compounds, as well as the corresponding palladium -allyl complexes. The complexes were isolated from the reaction mixtures by way of formation of 2,2'-bipyridine complexes and characterized by the elemental analyses and ¹H and ¹³C NMR spectra. The main direction of transformation of acyclic alcohols is formation of complexes with no alkyl substituents at the central carbon atom of the allyl ligand; with cyclic alcohols, exocyclic complexes are formed.     

Role of Pd(0) particles in oxidation of lower olefins in the catalytic system Fe(III)_Pd/ZrO<Subscript>2</Subscript>

Oxidation of metallic Pd(0) particles applied onto an oxide support with Fe(III) ions in a concentration not exceeding 0.06 M at 70°C was studied. In contrast to palladium black, with the supported catalyst Pd/ZrO₂ Pd(II) is formed in the solution in the concentration corresponding to the thermodynamic equilibrium. With an increase in the initial Fe(III) concentration, the equilibrium yield of Pd(II) increases. The initial reaction rate grows with an increase in the weight of the initial Pd-containing catalyst and in the initial Fe(III) concentration. The revealed kinetic relationships of the dissolution of Pd(0) in the reaction with Fe(III) aqua ions allow a conclusion that, in oxidation of lower olefins C₂-C₄ in the catalytic system Fe(III)_Pd/ZrO₂ in aqueous solution, Pd(II) is regenerated in the catalytic cycle by oxidation of Pd(I) species, rather than of Pd(0), with Fe(III) aqua ions.     

New one-step procedure for the synthesis of 6H-chromeno[4,3-b]quinolines and 8a,9,14,14a-tetrahydro-8H-benzo[5,6]chromeno[4,3-b]quinolines

Schiff bases generated in situ from substituted anilines and 2-allyloxybenzaldehyde underwent acid-catalyzed intramolecular Diels-Alder reaction followed by dehydrogenation to give 6H-chromeno[4,3-b]-quinolines. Under analogous conditions, derivatives of 2-allyloxynaphthalene-1-carbaldehyde were converted into 8a,9,14,14a-tetrahydro-8H-benzo[5,6]chromeno[4,3-b]quinolines. Possible dehydrogenation mechanisms are discussed. Original Russian Text ? M.M. Tomashevskaya, O.A. Tomashenko, A.A. Tomashevskii, V.V. Sokolov, A.A. Potekhin, 2007, published in Zhurnal Organicheskoi Khimii, 2007, Vol. 43, No. 1, pp. 75–80.     

New chiral ligands: 1,4-diols prepared from (<Emphasis Type="Italic">S</Emphasis>)-1-phenylethanol

The stereochemistry of condensation of dilithiated 1-phenylethanol with various carbonyl compounds was investigated. In most cases the reaction proceeds nonstreoselectively, and only in the condensation with PhCOBu-t and 2,4-(MeO)₂C₆H₃COPh only one of the diastereomeric diols prevailed. It was shown by XRD analysis that in the prevailing diastereomeric diol the newly formed chiral carbinol center possessed the same configuration as the initial alcohol. The synthesized diols form homochiral dimers in the crystal lattice.     

Formation of palladium nanoparticles in olefin oxidation with iron(III) aqua ions in the presence of the Pd/ZrO2/SO4 metallic catalyst

The reactions of the Pd/ZrO₂/SO₄-catalyzed oxidation of ethylene, propene, and but-1-ene in a 0.1–1.5 M solution of perchloric acid with iron(III) aqua ions to carbonyl compounds, viz., acetaldehyde, acetone, and methyl ethyl ketone, respectively, were studied. The formation of palladium nanoparticles (5 nm) in solution on contact of the initial heterogeneous Pd/ZrO₂/SO₄ catalyst with perchloric acid was proved by transmission electron microscopy. The palladium nanoparticles are assumed to play the key role in olefin oxidation with the iron(III) aqua ions. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 627–632, April, 2006.     

Reactions of 2-(α-Haloalkyl)thiiranes with Nucleophilic Reagents: IV. Alkylation of Sulfonamides with 2-Chloromethylthiirane. Synthesis and Properties of 3-(Arylamino)thietanes

Alkylation of primary and secondary sulfonamides with 2-chloromethylthiirane in the presence of alkali gives the corresponding N-(thiiran-2-ylmethyl)- and/or N-(thietan-3-yl)sulfonamides. The selectivity of the process depends on the solvent: in water, thiirane-thietane rearrangement products are formed exclusively, while ethanol favors Ad-E reaction leading to thiiranylmethyl derivatives. A procedure has been proposed for the synthesis of 3-(arylamino)thietanes which undergo selective acylation at the nitrogen atom. The possibility for synthesizing analogous derivatives of thietane 1-oxide and thietane 1,1-dioxide is considered.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 7, 2005, pp. 1046–1057.Original Russian Text Copyright © 2005 by Sokolov, Butkevich, Yuskovets, Tomashevskii, Potekhin.