Quantum model of selective multiphoton processes: The role of external (field) and internal (anharmonic coupling) detunings

Quantum equations of motion describing the energy transfer dynamics via intramolecular anharmonic coupling are presented and solved numerically. Dynamical features of the average excitations of a homogeneous system (SF₆) and a heterogeneous system (H/W) are quantitatively discussed in terms of the intramolecular vibrational relaxation (IVR) rates. Possible mechanisms of surface-enhanced desorption via low-power laser radiation are proposed.This work was supported in part by the Office of Naval Research, the Air Force Office of Scientific Research (AFSC), United States Air Force, under Grant AFOSR-82-0046 and the National Science Foundation under Grant No. CHE-8022874Camille and Henry Dreyfus Teacher-Scholar (1975–82)     

Theoretical studies of atmospheric molecules: SCF and correlated energy levels for the NO2, NO 2 + and NO 2 − systems

SCF and MC-SCF/CI calculations were carried out on the low-lying electronic states of NO₂, NO ₂ ⁺ and NO ₂ ^– , using a double-zeta quality basis set of contracted Gaussian functions. The calculations were performed primarily at the equilibrium geometry (R _NO = 2.25 a_o, _ONO=134 °) of theX ² A ₁ state of NO₂. SCF calculations on NO ₂ ⁺ in a linear conformation were also performed. Results are presented and compared with experiment and other calculations.Research supported in part by Air Force Delivery Orders F33615-72-M-5015 and MIPR889474-00117 and Air Force Office of Scientific Research and in part by the United States Energy Research and Development Administration.     

Electrophilic 1,5-addition of acyl chlorides to the azocyclopropane system of spiro(1-pyrazoline-3,1′-cyclopropanes)

1-Pyrazolines1–4, which contain a spiro cyclopropane fragment at the adjacent azo group, react selectively with acetyl (benzoyl) chloride or acetic anhydride in the presence of AlCl₃ to give high yields of the corresponding 1-acyl-3-(2-chloroethyl)-2-pyrazolines5–8, adducts of electrophilic 1,5-addition of acyl chlorides to the conjugated azocyclopropane system.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1993–1996, November, 1994.This study was financially supported by the Russian Foundation for Basic Research (grant No. 94-03-08902).     

Acylation of spiro(1-pyrazoline-3,1′-cyclopropanes) to form 1-acyl-3-(2-chloroethyl)-2-pyrazolines and transformation of bicyclic 2-pyrazolines into 1,4,5,6-tetrahydropyridazines

Strained polycyclic spiro(1-pyrazoline-3,1-cyclopropanes) react with acetyl or benzoyl chlorides at 0–15 °C regioselectively to give in high yields corresponding 1-acyl-3-(2-chloro-ethyl)-2-pyrazolines. Under the same conditions 6-ethenyl-4,5-diazaspiro[2,4]hept-4-ene gives a mixture of two pyrazolines resulting from the acyl group attack directed at different nitrogen atoms. Bicyclic pyrazolines-2 obtained by acylation of the cycloaddition products of diazocyclopropane with 3,3-disubstituted cyclopropenes transform under the action of hydrogen chloride to 1,4,5,6-tetrahydropyridazines in high yields.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2208–2211, November, 1995.The work was carried out with financial support of the Russian Foundation for Basic Research (Grant No. 94-03-08902).     

1,3-Dipolar cycloaddition of diazocyclopropane to strained cycloalkenes and conjugated dienes to give spiro(1-pyrazoline-3,1′-cyclopropanes)

Polycyclic spiro(1-pyrazoline-3,1-cyclopropanes) were obtained in 32–70 % yields by the reaction of diazocyclopropane generatedin situ with 2-methyltricyclo[3.2.1.0^2,4]oct-6-ene, spiro[2,4]hepta-4,6-diene dimer, benzvalene, spiro[2,3]hex-1-ene, methyl 1-methylcyclopropene-3-carboxylate, buta-1,3-diene, and 2-methylbuta-1,3-diene.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2199–2202, November, 1995.This study was financially supported by the Russian Foundation for Basic Research (Grant No. 94-03-08902).     

Relaxation of laser induced transient plasmas in liquids

Transient plasma is induced in H₂O, D₂O, CS₂, optical glass, and Plexiglas by single pulses of aQ-switched neodymium laser in the power density range of 0.4 to 0.9 GW cm^–2. The relaxation times for the simple exponential decay of intensity of a white continuum emitted by all samples have been determined. Possible mechanisms of the formation and decay of the plasmas are discussed.With 2 FiguresThe experimental part of this work was performed at the University of Utah and was supported in part by the Directorate of Chemical Sciences, Air Force Office of Scientific Research under Grant AFOSR-69-1717-D.     

Synthesis of α-(perfluoroalkyl)-ω-(trialkylsilyl)alkanols

The synthesis of alkanols of the general formula R₃Si(CH₂)_nCH(OH)R_F (n = 1–3) is elaborated and their behavior under GC-MS is studied.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1516-1519, June, 1996.     

Decomposition of hexafluoropropylene oxide in a strong IR field

Multiphoton dissociation (MPD) of hexafluoropropylene oxide (HFPO) under focused CO₂-laser radiation was studied. A high-energy channel of HFPO decomposition was revealed. The dependences of the MPD yield and the ratio between various channels of HFPO decomposition on the laser radiation frequency in the range from 967.7 to 1090.0 cm^–1, the incident radiation energy, and the initial pressure of HFPO were obtained. A considerable contribution of thermal decomposition of HFPO occurring outside of the irradiated zone to the total yield of its decomposition was established. An explanation for the pressure dependence of the yield of HFPO decomposition was suggested.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2174–2180, November, 1995.The authors are grateful to the Russian Foundation for Basic Research for financial support of this work (Project No. 94-03-09059).     

Thermal decomposition of strained spiro(1-pyrazoline-3,1′-cyclopropanes)

Pyrolysis (320–370 °C) of polycyclic 1-pyrazolines1 and2, obtained by 1,3-dipolar cycloaddition of diazocyclopropane to 3,3-dimethylcyclopropene and spiro[2,3]hex-1-ene, yields complex mixtures of isomeric hydrocarbons, substituted methylenecyclopropanes being the main components. Pyrolysis of 6-ethenyl- (4) and 6-methoxy-6-methylcarbonyl-4,5-diazaspiro[2,4]hept-4-enes (6) at 310–320 °C proceeds more unambiguously to give vinyl- (18) and 1-methoxy-1-methylcarbonylspiropentanes (20) in 85 and 95 % yields with respect to the transformed pyrazolines. Dediazotization of pyrazoline3 obtained from diazocyclopropane and benzvalene requires more drastic conditions (–440 °C) and produces indane.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2203–2207, November, 1995.This study was financially supported by the Russian Foundation for Basic Research (Grant No. 94-03-08902).     

α-Cyclopropylalkyl cations of a spiro[2.4] heptane system

-Cyclopropylalkyl cations of a spiro[2.4]heptane system, which are possible intermediates in solvolytic reactions of the corresponding cyclopropylalkanol derivatives, have been generated from compounds of the spiro(indan-2,1-cyclopropane), spiro(indan-1,1-cyclo-propane), and spiro[acenaphthylene-1(2H),1-cyclopropane] classes under long life conditions (HSO{in3}F-SO{in2}FCl-CD{in2}Cl{in2}, –100 °C).Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2194–2198, December, 1994.This work was carried out with the financial support of the Russian Foundation for Basic Research (Project No. 93-03-4715).     

Quantum-chemical study of the molecular and electronic structure of 2,2′-dithiodi(2-methyl-2,3-dihydro-1,4-thiazino[2,3,4-i,j]quinolinium)

Conformational isomerism of 2,2-dithiodi(2-methyl-2,3-dihydro-1,4-thiazino[2,3,4-i,j]quinolinium) has been studied by semiempirical MNDO and AM1 methods. Six symmetrical and unsymmetrical stationary states have been found. Optimum intramolecular rotations around single bonds have been considered. The possibility of the inversion of the reaction centers in nucleophilic and electrophilic reactions depending on the conformational state of the molecule has been shown. The spatial structure of one of the conformers found is similar to that typical of (–)-cystine. The observed constancy of some geometric and electronic parameters makes it possible to study the principal physicochemical properties of dithiazinoquinolinium compounds by the most sophisticatedab initio methods using small model structures, which are constructed by taking into account the variability of other geometric parameters, as an example.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2359–2364, December, 1995.The work was supported by the Russian Foundation for Basic Research (Project No. 93-03-18400).     

Oxidation of organic compounds by ozone on a surface

Adamantanol was obtained by the ozonization of adamantane, at -78 ° C, adsorbed on silica gel. Ozone does not decompose on silica gel in the absence of a substrate.Ozonization of adamantane on silica gel is accompanied by chemiluntinescence in the IR region. The chemiluminescence quenching is of first-order with the effective rate constantk'. In the range from 0.4 to 5 mmol, k' depends linearly on the amount of adamantane adsorbed on the silica gel. The activation energy E_a = 9.97±1.89 kcal mol^–1 and the pre-exponential factorA = (2.76±0.52) - 10⁶ were calculated from the temperature dependence ofk'.Translated from Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 375–378, February, 1996.     

Synthesis of ω-(2-oxocyclododecyl)alkanoic acids by alkylation of cyclododecanone with ω-haloalkanoic esters under conditions of phase-transfer catalysis

(-(2-Oxocyclododecyl)alkanoic acids have been obtained by alkylation of cyclododecanone with alkyl 3-bromopropionate, 5-iodopentanoate, and 11 -bromoundecanoate under conditions of phase-transfer catalysis.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2521–2523, December, 1995.     

Stable σ-adducts of 4,6-dinitrotetrazolo[1,5-a]pyridine with alkoxide anions

The reaction of 2-chloro-3,5-dinitropyridine with two equivalents of KN₃ in the presence of ROH results in stable Meisenheimer-type -adducts of 4,6-dinitrotetra-zolo[1,5-a]pyridine with RO^– anions (R = H, Alk, Ph). The mechanism of -complex formation was suggested. The structure of the -adduct with R = Me was established by IR and NMR spectroscopy and by X-ray diffraction analysis.For the preliminary communication, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1278–1283, July, 1994.This work was supported by the Russian Foundation for Basic Research (project code 93-03-5329).     

Dichloromethyl tert-butyl ketone in the Darzens reaction

The condensation of dichloromethyl tert-butyl ketone (1) with benzaldehyde, para-bromobenzaldehyde, and 2,4-dichlorobenzaldehyde under conditions for the Darzens reaction gives 1-aryl-1-chloro-4,4-dimethyl-2,3-pentanediones (2–4). In the case of nitrobenzaldehydes, the reaction products are 1-aryl-2-chloro-1,2-epoxy-4,4-dimethylpentanones (5 and 6), which isomerize to -chloroketones (7 and 8) upon prolonged storage or heating at reflux in benzene.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Science Center, Russian Academy of Sciences, 420083 Kazan. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 2, pp. 438–441, February, 1992.     

Synthesis and biological activity of yuccagenin bisrhamnoside

The two hydroxyls of yuccagenin can be glycosylated by Koenigs-Knorr condensation with acetobromorhammose in dichloroethane in the presence of mercuric cyanide. The bisrhamnoside of yuccagenin markedly lowers the cholesterol and triglyceride content in blood serum of healthy animals and animals with experimental hyperlipidemia.Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 242–243, May–June, 2000.     

Polyfluorinated hydrazones in organic syntheses

The reaction of poly- and perfluoroaldehyde hydrazones with hydrazine hydrate was studied. A new preparative method for obtaining the hitherto inaccessibleN,N-unsubstituted bis-hydrazones of polyfluorinated -oxoaldehydes was developed based on this reaction.For Part 2, seeIzv. Akad. Nauk, Ser. Khim., 1995, 2465 [Russ. Chem. Bull, 1995,44, 2360 (Engl. Transl.)].Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2526–2527, December, 1995.This study was financially supported by the Russian Foundation for Basic Research (Grant No. 94-03-08548) and the International Science Foundation (Grant Nos. NDL 000 and NDL 300).     

One-step synthesis of the chelate oxides of bis(trialkylantimony) by an oxidative method

The chelate oxides of bis(trimethylantimony) (Me₃SbL¹)₂O (i = 1 or 2, L¹-acetylacetonate, L² - trifluoroacetylacetonate) and bis(triethylantimony) (Et₃SbL¹)₂O have been obtained in 79–85% yields by a one-step oxidation of trialkylantimony withtertbutylhydroperoxide in the presence of -diketones in benzene at 20 °C.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 154–155, January, 1995.This work was carried out with financial support from the Russian Foundation for Basic Research (Project No. 94-03-08846).     

Organomineral sorbents based on clinoptilolite-containing tuffs

The anion-exchange properties of a new organomineral sorbent obtained by modification of clinoptilolite-containing tuffs by polyhexamethyleneguanidine have been studied after different periods of storage (time after synthesis) and numbers of sorption-regeneration cycles. The sorbent can be used as a cation- and an anion-exchanger simultaneously. Selectivity coefficients (exchange constants) for F^–, SO₄ ^2–, and HPO₄ ^2– ionsvs. Cl^– ions on modified clinoptilolite-containing tuffs have been determined. The modification improves the mechanical properties of clinoptilolite tuffs.For part 1, see Ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1554–1556, September, 1994.     

Zur Kenntnis der gemeinsamen Einwirkung von elementarem Selen und gasförmigem Ammoniak bzw. Ethylenimin auf Ketone

Elemental sulfur reacts with ketones and gaseous ammonia at room temperature yielding thiazoline-3 in excellent yields. Under the same conditions elemental selenium does not react at all. Attempts using the known techniques which have been applied in improving the reactivity of slowly reacting ketones in thiazoline-3-synthesis have been unsuccessful (Exp. No. 1–17). The reaction of -halogenketones with sodiumhydrogenselenide to synthesize -hydroselenoketones gives only the original ketones and selenium in almost quantitative yields (No. 18–23). The same is observed with -haloketones and sodium ore magnesium-diselenides (No. 24–45). The explanation of these unexpected results is the strong reducing power of the hydrogenselenide (No. 46–52). Even -bromoketones with activated bromine (i.g. by phenyl groups) were reduced by sodiumhydrogensulfide giving red undefinite oils. However, -chloroketones give -mercaptoketones in excellent yields (No. 53–61). Hydrogenselenide reduces -mercaptoketones to sulfur and ketones in the presence of triethylamine (No. 62–67). Also the transformation of -selenocyanketones to ,-diketodisenides by alkali or the oxidative hydrolysis of selenium-BUNTE salts does not work and gives elementary selenium only. Studies about the concomitant reaction of elementary selenium and ethylenimine on ketones were continued (No. 68–82).