Benzindazoles from triketones of the indan series

In the reaction of 2-acetonyl-and 2-phenacyl-2-phenylindan-1, 3-diones with hydrazine hydrate, the five-membered ring of the indandione system isomerizes into a six-membered ring forming derivatives of 5-hydroxy-1H-benz[g]indazole. Derivatives of 3,4-(CO)-benzoylenepyridazine have been isolated as intermediates. The benzindazoles mentioned have been obtained by independent synthesis from the corresponding 2-acyl-1, 4-dihydroxynaphthalenes.For part I, see [1].     

Synthesis of triketones of the phosphonoacetyldiacylmethane series

A new approach to the synthesis of the triketones of triacylmethane series containing a (dimetoxyphosphoryl) acetyl group was developed based on the reaction of β-diketones with dimethyl chloroacetylenephosphonate.     

Heterogyclization of triketones of the 2-(3-oxopropyl)-cyclohexane-1,3-dione series

Triketones of the 2-(3-oxopropyl) cyclohexane-1,3-dione series have been shown for the first time to react with boron trifluoride etherate to give the novel 5-oxo-5,6,7,8-tetrahydrochromylium fluoroborates, which in turn react with ammonia to give 5-oxo-5,6,7,8-tetrahydroquinolines. These were also obtained directly from ammonium acetate and 2-(3-oxopropyl)cyclohexane-1,3-diones.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 915–918, July, 1985.     

Characteristics of heterocyclization of triketones of the 2-(3-oxopropyl)cyclohexane-1,3-dione series with hydroxylamine hydrochloride

A rearrangement that leads to the formation of mixtures of 2,4- and 2,3-diaryl-substituted 5-oxotetrahydroquinoline oximes was observed in the heterocyclization of oxo 1,5-diketones of the 2-(3-oxopropyl)cyclohexane-1,3-dione series, as well as in the recyclization of 5-oxotetrahydro-4H-chromenes, in the presence of excess hydroxylamine hydrochloride. It was established that the rearrangement proceeds only when electron-donor groups are present in the starting compounds.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 209–214, February, 1990.     

Synthesis of photoreactive polyimide having indan structure

Polyimide containing an indan unit and alkyl moiety with a high molecular weight was prepared from 5,7‐diamino‐1,1,4,6‐tetramethylindan and 3,3′,4,4′‐benzophenone tetracarboxylic dianhydride. This polyimide was amorphous and soluble in common organic solvents, such as tetrahydrofuran, chloroform, and cyclopentanone. Thermogravimetry of the polyimide showed good thermal stability, indicating that a 10% weight loss of the polyimide was observed at 500 °C in nitrogen. The glass‐transition temperature of the polyimide was not observed by DSC measurement between room temperature and 400 °C at a heating rate of 10 °C/min (Apparatus: DSC3100 MAC Science Co., Ltd.). Transparency of the polyimide at 365 nm was 80%. The polyimide acted as a photosensitive resist of negative type by UV radiation. The resist had a sensitivity of 31 mJ/cm² and a contrast of 2.3 when it was developed with cyclopentanone at room temperature. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 423–428, 2002     

四氢化萘热解中甲基茚满生成机理的密度泛函计算

采用量子化学密度泛函方法对四氢化萘热解过程中甲基茚满的生成机理进行计算。结果表明,热解产物甲基茚满的主要存在形式是1-甲基茚满;其主要生成反应途径是,首先通过自由基和四氢化萘间的氢转移反应生成β-四氢化萘基,然后β-四氢化萘基上的氢化芳环经缩环反应生成1-甲基茚满。提高温度能促进1-甲基茚满生成反应的进行,但对其生成反应路径没有太大影响。     

Syntheses based on aldehydes of the thiophene series

Summary The use of 2,5-thiophenedicarboxaldehyde monoacetal in synthesis makes it possible to prepare unsymmetrical bifunctional thiophene derivatives.This article is published in accordance with a resolution of the Conference of Chief Editors of Journals of the Academy of Sciences of the USSR, July 12, 1962, as a dissertation paper by V. I. Rogovik.     

New aspects of the mechanism for the thermal hydrocracking of indan and tetralin

Thermal cracking of indan and tetralin in the gas phase was carried out in a flow reactor at 500°C and 8 MPa pressure in the presence of hydrogen and nitrogen. The primary reactions are ring cracking and dehydrogenation, regardless of the nature of the second component. Ring cracking, however, is strongly enhanced by the presence of hydrogen. This enhancement becomes less significant with increasing concentration of the hydrocarbon in the gaseous reaction mixture and also with a decreasing ratio of hydrogen to hydrocarbon. At hydrocarbon concentrations larger than approximately 0.5 g·mol/L and H₂-to-HC molar ratios of 1 or lower, conversion rates are almost equal in hydrogen and in nitrogen. Ring cracking exhibits different kinetic behavior in nitrogen than in excess of hydrogen. This illustrates the occurrence of two complementary cracking mechanisms, each of which can dominate in certain concentration ranges. The H₂-initiated ring cracking is gradually transformed into a hydrogen-donor mechanism as the leading reaction scheme when the concentration of indan or tetralin is increased.     

Thermal hydrocracking of indan. Effects of the hydrogen pressure on thekinetics and Arrhenius parameters

The kinetics of the thermal hydrocracking of indan were investigatedin a high-pressure flow reactor at temperatures from 470 to 530°C, total pressures of up to 300 atm, and molar ratios from 3 to 40. The effect of the hydrogen pressure was reflected especially in a change of the experimental rate equations for the formation of toluene from r_T=k [indan]^0.5 [hydrogen] to r_T=k′ [indan] ^0.75[hydrogen]^0.75 with hydrogen partial pressureincreasing from 73 to 230 atm. The rate equation of n-propylbenzene remained constant at r_Pr=k″ [indan] [hydrogen]^1.5. Simultaneously the Arrheniusparameters of toluene changed significantly, while those of n-propylbenzene remained unchanged. The observed effect of the hydrogen pressure is explained as a change inthe rates of the intermediate reactions; it provides an excellent agreementbetween the theoretical and experimental data. It was found that the steady-state concentration of the hydrogen atoms, which act as chain carriers in the thermal hydrocracking, was much smaller than the thermodynamic equilibrium concentrations     

The reaction of vicinal triketones with cumulative phosphorus ylides. Synthesis of phosphoranylidenecyclobutanes

1,2,3-Indantrione ( 1 ), diphenylpropanetrione( 6 ), and alloxan ( 8 ) can be converted by reactions with ketenylidene-( 2a ) and thioketenylidenetriphenylphosphorane ( 2b ) into phosphoranylidenecyclobutanes ( 5 , 7 , and 9 ). The structures of the new cyclic compounds were confirmed on the basis of elemental analysis and spectral studies.     

Selective synthesis of cyclic peroxides from triketones and H2O2

A method for the assembly of tricyclic structures containing the peroxide, monoperoxyacetal, and acetal moieties was developed based on the acid-catalyzed reaction of β,δ-triketones with H(2)O(2). Tricyclic compounds are formed selectively in yields from 39% to 90% by the reactions with the use of large amounts of strong acids, such as H(2)SO(4), HClO(4), or HBF(4), which act both as the catalyst and as the co-solvent. The reaction is unusual in that, despite the diversity of possible peroxidation pathways giving cyclic compounds and oligomers, the reaction proceeds with high selectivity and produces tricyclic peroxides via the monoperoxidation of the carbonyl groups in the β-positions and the transformation of the δ-carbonyl group into the acetal one. The syntheses are scaled up to tens of grams, and the resulting peroxides can be easily isolated from the reaction mixture.     

Reaction of γ-pyrones with 1,3-bis(dicyanomethylene)indan

The condensation of -pyrones with 1,3-bis(dicyanomethylene)indan leads to the corresponding deeply colored 2-(pyran-4-ylidene)-1,3-bis(dicyanomethylene)indans. The reaction of the latter with primary aliphatic or aromatic amines leads to replacement of the pyran oxygen by an amino group. The resulting compounds are zwitterions and possesses dichroic properties. The IR and UV spectra, and also the dichroic spectra of the compounds obtained in a liquid crystal are given. A qualitative explanation of the nature of the absorption bands of these compounds in the visible region of the spectrum is presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 603–608, May, 1985.     

Plant-protection agents based on compounds of the pyridine series (review)

The principal derivatives of pyridine bases that display pesticide activity are examined. It is shown that the accessible oxygen-containing functional derivatives of pyridine are intermediates for the synthesis of a large number of promising plant-protection agents.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 579–587, May, 1989.     

Two-color resonantly enhanced multiphoton ionization and zero-kinetic-energy photoelectron spectroscopy of jet-cooled indan

We report studies of supersonically cooled indan using two-color resonantly enhanced multiphoton ionization and two-color zero-kinetic-energy photoelectron spectroscopy. With the aid of ab initio and density-functional calculations, vibrational modes of the first electronically excited state of the neutral species and those of the cation have been assigned, and the adiabatic ionization energy has been determined to be 68458 +/- 5 cm(-1). Similar to the ground state and the first electronically excited state of the neutral molecule, the ground state of the cation is also proven to be nonplanar, with an estimated barrier of 213 cm(-1) and a puckering angle of 15.0 degrees. These conclusions will be discussed in comparison with a previous study of an indan derivative 1,3-benzodioxole.     

Isostructural series of nine-coordinate chiral lanthanide complexes based on triazacyclononane

Nonadentate ligands based on triazacyclononane incorporating pyridyl-2-phosphinate groups form an isostructural series of complexes with Ln ions in the solid state and in solution. The Ln ion is effectively shielded from the solvent environment. Crystal structures reveal a rigid C(3)-symmetric tricapped trigonal-prismatic coordination geometry that is maintained in solution for the methyl and phenylphosphinate series, as shown by multinuclear NMR analysis. Variable-temperature measurements of the field dependence of the water proton relaxivity in gadolinium complexes indicate that these systems exclude solvent from the primary coordination environment and minimize the second sphere of solvation. The electronic relaxation time for the gadolinium methylphosphinate complex has been estimated to be 550 (±150) ps by EPR and NMR methods, compared to values of around 0.30-0.05 ps for the terbium-ytterbium series, deduced by analyzing the field dependence (4.7-16.5 T) of the (31)P NMR longitudinal relaxation times. Values are compared with analogous azacarboxylate ligand complexes, supporting a key role for donor atom polarizability in determining the electronic relaxation. Spectral emission behavior in solution of samarium, europium, terbium, and dysprosium complexes is compared, and the resolved RRR-Λ and SSS-Δ complexes show strong circularly polarized luminescence. The molecular quadratic hyperpolarizability ?β(HLS)? has been measured in solution using hyper-Raleigh light-scattering methods, for the whole series of lanthanide complexes of one ligand. The values of ?β(HLS)? reach a maximum around the center of the series and are not simply dependent on the number of f electrons, suggesting a dominant contribution from the octupolar rather than the dipolar term.