Reaction of 2-acetylbenzothiazole with 2-formylbenzothiazole

Products of condensation of 2-acetylbenzothiazole with 2-formylbenzothiazole and other aldehydes of the heterocyclic series were obtained, and their structures and properties were investigated. It is shown that some of them react with acids or alkalis to give dyes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 644–648, May, 1982.     

Reaction of 2-Alkoxypropenals with 2-Mercaptoethanol

The reaction between 2-alkoxypropenals and 2-mercaptoethanol was studied at 20 and 60°C by means of ^1HNMR and GC-MS methods. Under kinetically controlled conditions (20°C, 7-30 days) with no catalyst the addition of 2-mercaptoethanol to 2-alkoxypropenals occurs along Markownikoff rule. The arising 2'-hydroxyethylthio-2-alkoxypropanal undergoes isomerization into the 2-hydroxy-3-alkoxy-3-methyl-1,4-oxathiane that at heating in the presence of catalytic amounts of acids is converted into 2-methyl-2-formyl-1,3-oxathiolane. The reaction of 2-alkoxypropenals with 2-mercaptoethanol at heating (60°C, 3 h) in the presence of acids affords 2-methyl-2,2'-bi(1,3-oxathiolane) even at 2-mercaptoethanol deficit. At the double excess of the latter the 2-methyl-2,2'-bi(1,3-oxathiolane) was obtained in quantitative yield. The presumable schemes of conversion of 2-hydroxy-3-alkoxy-3-methyl-1,4-oxathiane into 2-methyl-2-formyl-1,3-oxathiolane and 2-acetyl-1,3-oxathiolane are discussed.     

Reactions of 2-amino- and 2-hydrazinobenzimidazoles with 2-acyldimedones

The reaction of 2 formyldimedone with 2-amino- and 2-hydrazinobenzimidazoles at 20°C in ethanol gave 2-(2-benzimidazolyl)aminomethylene- and 2-[2-(2-benzimidazolyl)hydrazinomethylene]-5,5-dimethylcylohex-anediones, while this reaction carried out in ethanol at reflux in the presence of acid gave 2,2-dimethyl-4-oxo 1, 2, 3, 4-tetrahydroquinazolino(1, 2-a]benzimidazole and 1-(2-benzimidazolyl)-6, 6-dimethyl-4-oxo-4, S, 6, 7-tetrahydroindazole, respectively.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 247–252, February, 1996.     

Reaction of CH2Cl with O2

The elementary reaction of CH2Cl+O2 in gas phase was investigated by time-resolved FTIR emission spectroscopy. Vibrationally excited products CO (v·4), and CO2 (o3, v·7) were observed. The yield ratio of CO/CO2(o3) was 72.2§7. The reaction pathways were studied theoretically at QCISD//UB3LYP/6-311++G(d,p) level. In the beginning of the reaction, CH2Cl radical associated with O2 to form CH2ClOO, followed by removal of the Cl atom to yield another intermediate dioxirane CH2OO. Subsequently, a series of isomerization and decomposition of the CH2OO took place, yielding the ˉnal products of CO and CO2. The calculated result was in consistent with the experimental observation.     

Condensation of Cp2TiCI2 with Tetraamines

The synthesis of titanium polyamines from tetraamines is general and rapid. Systems utilizing equimolar quantities of reactants produce linear products, whereas tri- and tetra-substitution occurs when excess Cp₂TiCl₂ is used. The products exhibit moderate high-temperature stability but poor low-temperature stability, with degradation occurring via nonoxidative routes to ca. 200°C, and by oxidative routes in air at higher temperatures.     

Reactions of 2-Nitro- and 2-Bromo-2-nitroethenylphosphonates with Anthracene

Bis(2-chloroethyl) 2-nitro- and 2-bromo-2-nitroethenylphosphonates react with anthracene along two competing pathways: [4+2] cycloaddition and electrophilic substitution; in the case of the bromo derivative, the resulting products undergo dehydrobromination under the reaction conditions to form anthracene- and dihydroanthracene-containing nitroethenylphosphonates.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 5, 2005, pp. 729–733.Original Russian Text Copyright © 2005 by Anisimova, Kuzhaeva, Berkova, Deiko, Berestovitskaya.     

Fullerite with intercalated freon Ch2F2

Fullerite C₆₀ with intercalated CH₂F₂ (Freon-32) was prepared for the first time. The sample was studied by elemental analysis, X-ray powder diffraction, mass spectrometry, and IR spectroscopy. The composition of the sample was found to be (CH₂F₂)C₆₀. The sample had a face-centered cubic lattice with the lattice parameter (1.4284 nm) much larger than that of pure fullerite (1.416 nm). The gas released from the sample during heating in a vacuum to 450°C largely consisted of initial Freon (mass spectrometry data); no Freon destruction products were observed at this temperature. The C-F stretching vibration frequency (1058 cm^?1) was shifted in (CH₂F₂)C₆₀ by 30 cm^?1 toward lower wave numbers compared with the gas phase. The absorption bands at 1182 and 1428 cm^?1 (IR active modes (F _1u ) of high-symmetry (I _h ) C₆₀ molecules) did not change their positions in the intercalate.     

Chemiluminescent reaction of Al2 with F2

The reaction of Al₂ with F₂ is shown to proceed in a single collision to yield one AlF product in high Rydberg states and one in the ground state with a large cross section.     

Gas-phase reactions in plasmas of SF6 with O2: Reactions of F with SOF2 and SO2 and reactions of O with SOF2

The plasma chemistry of SF₆/O₂ mixtures is particularly complicated because of the large number of possible reactions. Over a wide range of conditions, products including SF₄, SOF₄, SOF₂, and SO₂F₂ can be formed but thre is considerable uncertainty about the major reactions which contribute to the formation of these species. In this work reactions of oxygen atoms with SOF₂ and fluorine atoms with SOF₂ and SO₂ have been studied in order to determine the principal sources of SO₂F₂ in these plasmas. Reactions were studied at 295 K in a gas flow reactor sampled by a mass spectrometer. No reaction could be detected between oxygen atoms and SOF₂, which for the conditions employed, means that the upper limit for the reaction rate coefficient is 1×10^–14 cm³ sec^–1. The reaction of fluorine atoms with SOF₂ was studied with the helium bath gas number density ranging from 3.1×10¹⁶ to 2.0×10¹⁷ cm^–3. Within this range the rate coefficient increased with increasing [He] from (4.1 to 10.8)×10^–14 cm³ sec^–1. SO₂ was found to react with fluorine atoms with a rate coefficient which appeared to be independent of the helium bath gas number density over the range given above. The possibility that this reaction occurred entirely on the walls of the reactor is discussed.     

Reaction of Cp2ZrCl2 with Inorganic Amides

The reactions of [η⁵‐Cp₂ZrCl₂] (Cp = η⁵‐C₅H₅) with [K(THF)_n][N(PPh₂)₂] (n = 1.25—1.5) and K[CH(PPh₂NSiMe₃)₂] are reported. The first reaction led to the monoamido complex [η⁵‐Cp₂Zr(Cl)N(PPh₂)₂] in which the {(Ph₂P)₂N}^— ligand — via a phosphorous and the nitrogen atom — is coordinated to the zirconium atom in a chelating (η²) fashion. Reaction of the potassium methanide compound, K{CH(PPh₂NSiMe₃)₂} with zirconocene dichloride yield the carbene‐like mono cyclopentadienyl complex [η⁵‐CpZr(Cl){C(PPh₂NSiMe₃)₂}]. The complex is formed by a salt metathesis and concomitant a cyclopentadiene extrusion.     

Reaction of 2-arylhydrazono-2-cyano-N-cyclohexylthioacetamides with halocarbonyl compounds

The reaction of arylhydrazonocyanothioacetamides containing an N-cyclohexyl fragment with chloroacetone, phenacyl bromide, ethyl chloroacetate, and chloroacetonitrile was investigated. It was shown that a substituent with a large steric effect in the thioamide group alters the direction of intramolecular cyclization of the thioimidate intermediate. In contrast to the Hantsch reaction, which usually leads to the formation of thiazoles under these conditions, the only products are 3-amino-4-arylhydrazono-4,5-dihydrothiophenes. Dedicated to Prof. Dr. E. Lukevics on his 70th birthday __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 22–33, January, 2007.     

2-Nitro-and 2-bromo-2-nitroethylphosphonates in the reaction with sodium azide

The reactions of phosphorylated 2-nitro-and 2-bromo-2-nitroethenes with sodium azide involve 1,3-dipolar cycloaddition to form triazoles, aziridines and isomeric vinyl azides. The latter products were isolated as a mixture of structural isomers. The structure of the obtained compounds was determined by IR and ¹H and ³¹P NMR spectroscopy.     

Gas phase reactions of SiF2 with F2 and Cl2

Reactions of SiF₂ radicals have been studied in a fast-flow system. Rate constants at 295 K of (4.7±0.3)×10⁻¹³ cm³ molecule⁻¹ s⁻¹ for the reaction of SiF₂ + F₂, and (5.1±0.6)×10⁻¹³ cm³ molecule⁻¹ s⁻¹ for SiF₂ + Cl₂ were obtained. No reaction was observed with O₂ and H₂. SiF₂ was detected by laser-induced fluorescence, and lifetime observations and an excitation spectrum are reported.     

Reaction of perfluoro-2-methylpent-2-ene with azoles

Perfluoro-2-methylpent-2-ene reacts with pyrazole, imidazole, 1,2,4-triazole, and benzotriazole to give products of the replacement of the vinylic fluorine atom. In the case of imidazole, the product of allylic fluorine substitution, 1,3-bisimidazolylperfluoro-2-methylpent-2-ene, is also formed. The structures of the products were confirmed by spectral data. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 835–837, April, 1997.     

Manganese catalysed asymmetric cis-dihydroxylation with H2O2

High turnover enantioselective alkene cis-dihydroxylation is achieved with H(2)O(2) catalysed by manganese based complexes containing chiral carboxylato ligands.     

Substitutive addition reactions of 2-alkylidenecyclanones with 2-alkylfurans

The reaction of 2-alkylidenecyclanones with 2-alkylfurans in an acid medium leads to the formation of substitutive addition products, 1-(2-cyclanon-1-yl)-2-(5-alkylfuryl)alkanes.     

Oxidation of 2-cyanoprop-2-enethioamides with hydrogen peroxide

Oxidation of (E)-3-aryl-2-cyanoprop-2-enethioamides with 32% H₂O₂ under mild conditions gave (E)-3-aryl-2-cyano-1-iminioprop-2-ene-1-sulfenates in 70–88% yields. Under the conditions of the Radziszewski reaction (H₂O₂, 10% aqueous KOH) or upon prolonged treatment with H₂O₂, (E)-3-aryl-2-cyanoprop-2-enethioamides underwent transformations leading to complex mixtures of oxidation products. In some cases, 3-aryloxirane-2,2-dicarboxamides were isolated from those mixtures in low yields (<20%). Treatment of 3-arylamino-2-cyanoprop-2-enethioamides with the system H₂O₂/KOH in ethanol afforded (arylaminomethylidene)malononitriles.