Synthesis and properties of 1,3-dioxolanium salts (review)

Methods for the synthesis of 1,3-dioxolanium salts — a new class of carboxonium cations that are finding application in organic synthesis — and their structure and properties are examined.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 869–882, July, 1975.     

Synthesis and properties of 1,3-dioxanium salts (review)

Syntheses, structures, spectral characteristics, and chemical properties of 1,3-dioxanium salts are reviewed.Kuban State Technological University, Krasnodar 350072, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 291–316, March, 1999.     

Synthesis,structure, spectral properties,and electrochemistry of bis(crown ether) containing 1,3-distyrylbenzenes

The reaction of tetraethyl [1,3-phenylenedi(methylene)]bis(phosphonate) with formyl derivatives of benzocrown-ethers or formyl derivatives of o-dimethoxybenzene lead to high yield formation of the respectful bis(crown ether) containing 1,3-distyrylbenzenes or tetramethoxy-substituted 1,3-distyrenebenzenes. NMR spectra and quantum-chemical calculations showed the prevalence of unsymmetrical syn/anti,(syn,anti),syn/anti-conformations in 1,3-distyrylbenzenes. 1,3-Distyrylbenzenes absorb in shorter wavelength spectral region and have a weaker fluorescence than 1,4-distyrylbenzenes. The difficulty in the electrochemical reduction of 1,3-distyrylbenzenes comparing with 1,4-distyrylbenzenes is due to a less effective conjugation system in the metaderivatives.     

Synthesis,structure, and luminescent properties of two novel polynuclear complexes of 1,3-di(pyridin-2-yl)propane-1,3-dione

Two complexes, {[Cd₆(o-dppd)₂(μ²-Cl)₆(μ³-Cl)₂(DMF)₂(H₂O)₂Cl₂]·DMF·CH₃OH} _n (I) (DMF = N,N-dimethylformamide; o-dppdH = 1,3-di(pyridin-2-yl)propane-1,3-dione) and [Cu₄(o-dppd)₂(OAc)₄(OH)₂]·4H₂O (II), were synthesised and characterised by single-crystal X-ray diffraction, elemental analysis, IR, solid fluorescence and TGA. The results showed that complex I had a rodshaped polynuclear chain with hexacoordinating Cd atoms bridged by oxygen, μ²-Cl and μ³-Cl; complex II was a tetranuclear oligomer. In general, supramolecular architectures are constructed through hydrogen-bonding and π-π stacking interactions. I shows luminescence.     

Synthesis,reactions, and structures of 1,3- and 1,2-ditelluroles (review)

Data on methods for the synthesis of 1,3- and 1,2-di-telluroles and tetratellurofulvalenes and their reactions and structures are systematized and correlated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 291–304, March, 1991.     

Synthesis, structure, and properties of phosphorus-containing bis(amidrazones)

Previously unknown ethenylphosphonic derivatives of bis(amidrazones) were prepared. According to spectroscopic data and quantum-chemical calculations, these compounds exist as phosphonium salts of a symmetrical linear structure with trans arrangement of the amidrazone fragments. In alkaline solutions, they are unstable and decompose to form triarylphosphine oxides. In contrast to ordinary amidrazones, their phosphorus-containing derivatives do not tend to form complexes with transition metals.     

Synthesis, structure, and properties of chromium(III) sulfates

Reactions between CrO₃ and 50- are studied at temperatures up to the boiling point of the acid. Depending on the H₂SO₄ concentration and synthesis temperature, Cr₂(SO₄)₃, CrH(SO₄)₂, (H₃O)[Cr(SO₄)₂], Cr₂(SO₄)₃·H₂SO₄·4H₂O (gross formula), and (H₅O₂)[Cr(H₂O)₂(SO₄)₂], are obtained as identified reaction products in addition to the incompletely characterized chromic-sulfuric acid. The Cr^III-based sulfates are characterized by X-ray powder diffraction, thermogravimetric, and magnetic susceptibility measurements. The nuclear and magnetic structures of Cr₂(SO₄)₃ at are determined, the structure type of (H₃O)[Cr(SO₄)₂] is established, and the crystal structure of (H₅O₂)[Cr(H₂O)₂(SO₄)₂] is firmly stipulated. Magnetic susceptibility data suggest that the samples of CrH(SO₄)₂ are in a micro-crystalline rather than in an amorphous state. All Cr^III-based sulfates synthesized in this study appear to undergo paramagnetic-to-antiferromagnetic transitions at around .     

Dihydrothiophenes. Synthesis and properties (review)

The literature data on the methods of synthesis and properties of 2,3-dihydrothiophene and 2,5-dihydrothiophene have been correlated for the first time. A. N. Kosygin Moscow State Textile Academy, Moscow 117918, Russia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1299–1324, October, 1998.     

Synthesis, molecular structure, and polymerization reactivity of ethylenebis(1,3-dimethylcyclopentadienyl)zirconium dichloride

An ethylene-bridged zirconocene complex bearing methyl substituents only on the cyclopentadienyl carbons adjacent to bridge point, ethylenebis(1,3-dimethylcyclopentadienyl)zirconium dichloride (5) was synthesized. Crystal structure of 5 was determined. The complex, 5, when activated with MAO, shows better comonomer incorporation ability than [Ph₂C(Fluo)(Cp)]ZrCl₂ in the ethylene–norbornene copolymerization but it is not better than rac-Et(Ind)₂ZrCl₂ for the ethylene-1-hexene copolymerization in terms of activity and comonomer incorporation.     

Synthesis, crystal structure and magnetic properties of a novel manganese(II)-nitronyl nitroxide-azido(μ_(1,1) and μ_(1,3)) one-dimensional complex

A novel one-dimensional manganese(Ⅱ) complex containing nitronyl nitroxide radical [Mn2(IM2-py)2(Ac)2((μ1.1-N3)(μ1,3-N3) . EtOH]n was synthesized and characterized structurally and magnetically. It crystallizes in the monoclinic space group p21/n. Each Mn(Ⅱ) ion is six-coordinated in a distorted octahedral environment. The two N atoms of the nitronyl nitroxide radical and the two O atoms of acetate ligands are in the equatorial plane, whereas the two different azido bridging ligands are in trans axial position. Mn(Ⅱ) ions are linked by nitrogen atom of μ1,1-azido and oxygen atoms of two carboxy groups to form a Mn-Mn unit. Mn-Mn units are linked by azido ligands through u1,3 bridging style to form a one-dimensional chain. The compound is connected by the coordination bonds,π-π interactions and hydrogen bonds as a three-dimensional structure. Magnetic susceptibility data support that there are stronger antiferromagnetic interactions between the radical and Mn(Ⅱ) ion, weak antiferromagnetic inter     

Synthesis of heterocyclic compounds from cyclohexane-1,3-diones (review)

The literature data on the synthesis of partially hydrogenated heterocyclic compounds containing a 3-oxocyclohexene structural fragment condensed with five-, six-, or seven-membered oxygen-, nitrogen-, and sulfur-containing heterorings from cyclohexane-1,3-diones and their derivatives are examined in this review.     

Synthesis and properties of 2-oxooxazolopyridines (review)

Published data on the synthesis and properties of 2(3H)-oxooxazolo[4,5-b]-, 2(1H)-oxooxazolo[5,4-b]-, and 2(3H)-oxooxazolo[4,5-c]pyridines up to 1997 are reviewed.Riga Technical University, Riga, Latvia. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 168–183, February, 1999.     

Synthesis, structure and properties of molybdenum(0) bialkyne complexes

The reaction of Mo(NN)(CO)₄ (NN = bipyridine, phenathroline) with CH₃OOCCCCOOCH₃ (DMAC) gives Mo(NN)(CO)₄(DMAC)₂. An X-ray diffraction study of the product (NN = bipyridine) indicates that the two CO groups are cis to each other, while the two DMAC ligands are in trans arrangement, and are mutually perpendicular with each DMAC eclipsing and N---Mo---CO vector. In solution, the DMAC ligands appear to rotate about the Mo---DMAC bond as shown by the fluxional behavior in the NMR spectra of the products.     

Synthesis,characterization, and X-ray crystallographic structure of 1,3-dimethyl-2(3H)-imidazoleselone

The reaction of elemental Se with 1,3-dimethylimidazolium iodide in methanolic K₂CO₃ yields 1,3-dimethyl-2(3H)-imidazoleselone for which three addition products, two with bromine and one with iodomethane, have been synthesized and for which X-ray crystallographic analysis shows the structure to consist of a selenium-substituted planar heterocyclic ring with bond distances and angles significantly different from those noted for the previously reported sulfur analog [1,3-dimethyl-2(3H)-imidazolethione, dmit]. Crystal data: C₅H₈N₂Se, space group C mcm, M = 175.03, a = 8.625(3), b = 11.447(6), c = 6.900(4) Å, V = 681.24 ų, Z = 4, D_c = 1.707 g cm⁻³, D₀ = 1.68 g cm⁻³, λ = 0.71073 Å (Mo-K_α), μ = 5.35 mm⁻¹, R = 0.034, and R_w = 0.031.     

1,3-Benzothiazines (review)

Data on the methods for the synthesis of 1,3-benzothiazines and their derivatives and their chemical properties and physiological activity are correlated.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 291–308, April, 1979.     

Cyclometallated ruthenium(III) complexes: Synthesis,structure and properties

Reactions of Schiff bases (H₂apahR) derived from acetophenone and acid hydrazides, triethylamine and [Ru(PPh₃)₃Cl₂] (1:2:1 mole ratio) in methanol provide cyclometallated ruthenium(III) complexes of formula trans-[Ru(apahR)(PPh₃)₂Cl] in 74–81% yields. The complexes have been characterized by elemental analysis, magnetic susceptibility, spectroscopic (infrared, electronic and EPR) and electrochemical measurements. X-ray crystal structures of two representative complexes have been determined. In each complex, the metal centre is in distorted octahedral CNOClP₂ coordination sphere assembled by the C,N,O-donor meridionally spanning apahR^2?, the chloride and the two mutually trans-oriented PPh₃ molecules. All the complexes are one-electron paramagnetic (μ_eff. = 1.85–1.98 μ_B) and display rhombic EPR spectra in frozen (120 K) dichloromethane-toluene (1:1) solution. Electronic spectra of the complexes display several absorptions within 470–270 nm due to ligand-to-metal charge transfer and ligand centred transitions. The complexes are redox active and display a Ru(III) → Ru(II) reduction and a Ru(III) → Ru(IV) oxidation in the potential ranges ?0.66 to ?0.70 V and 0.75 to 0.80 V (vs. Ag/AgCl), respectively.     

Palladium(II) benzazolylformazanates: Synthesis,structure and optical properties

The Pd(II) complexes of 1-aryl-5-benzazolyl- and 1,5-dibenzimidazolylformazans are synthesized and characterized by UV and IR spectroscopy, mass spectrometry, and magnetochemical studies. The complexes exhibit the intense absorption in the near-IR spectral region (820–1020 nm). The interaction of the complexes with amines leads to the transformation into binuclear palladium formazanates, which absorb at 620–680 nm and whose structures were confirmed by X-ray diffraction analysis.     

Synthesis,complexing properties,and selectivity of bis(diphenylphosphorylmethyl) ethers of oligoethylene glycols. Crystal structure of 1,3-bis(diphenylphosphoryl)-2-oxapropane

A convenient method of synthesis of phosphoryl-substituted podands with dipehnylphosphorylmethyl end groups of the general formula Ph₂P(O)CH₂O(CH₂CH₂O)_nCH₂P(O)Ph₂ (Lⁿ, n = 0–6) is described. The stability constants of the complexes of the podands with alkali metal 2,4-dinitrophenolates were determined by conductometry. The ion-selective properties of the podands with respect to alkali and alkaline-earth metal cations were assessed by ionometry. The crystal structure of 1,3-bis(diphenylphosphoryl)-2-oxapropane was established by X-ray diffraction analysis.     

Synthesis, crystal structure and electrochemical properties of bis(ethylenedioxy)tetraselenafulvalene (BEDO-TSeF)

Bis(ethylenedioxy)tetraselenafulvalene (BEDO-TSeF) has been synthesized using elemental selenium as the only source of the selenium atoms, and its crystal structure and electrochemical properties are examined and compared with its sulfur analogues.