An <Emphasis Type="Italic">ab initio </Emphasis> Quantum-Chemical Study of C<Subscript>6</Subscript>H<Subscript>5</Subscript>S(O)CH<Subscript>3</Subscript> and C<Subscript>6</Subscript>H<Subscript>5</Subscript>S(O)CF<Subscript>3</Subscript>

The potential functions of internal rotation around the C -S bond in the C₆H₅S(O)CH₃ and C₆H₅S(O)CF₃ molecules were obtained by ab initio MP2(full)/6-31+G* calculations. The stationary points were identified by solving the vibrational problems. The structures in which the plane of the C -S-C bonds is approximately perpendicular to the benzene ring plane correspond to the energy minimum. The barriers to rotation around the C -S bond, corrected for the zero-point vibration energy, are 21.29 [C₆H₅S(O)CH₃] and 28.98 [C₆H₅S(O)CF₃] kJ mol⁻¹. The bond angles (deg) are as follows: 95.7 (CSC), 107.1 (C SO), 106.3 (C SO) in C₆H₅S(O)CH₃; 93.5 (CSC), 108.2 (C SO), 105.2 (C SO) in C₆H₅S(O)CF₃. The bond lengths are as follows (Å): 1.520 (S=O), 1.804 (C -S), 1.810 (C -S) in C₆H₅S(O)CH₃; 1.507 (S=O), 1.799 (C -S), 1.870 (C -S) in C₆H₅S(O)CF₃. According to the results of NBO calculations, the formally double S=O bond consists of a strongly polarized covalent σ bond (S→O) and an almost ionic bond. An increase in the S=O bond multiplicity relative to a single bond is mainly due to hyperconjugation by the mechanism n(O)→σ*(C -S) and n(O)→σ*(C -S) and, to a lesser extent, by interaction of the oxygen lone electron pairs with the Rydberg orbitals of the S atoms, characterized by a large contribution of the d component.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 1, 2005, pp. 96–104.Original Russian Text Copyright © 2005 by Bzhezovskii, Il’chenko, Chura, Gorb, Yagupol’skii.     

Heteroatomic derivatives of aziridine

The reaction of ethyleneimine with sulfenyl chlorides RSCl at –10 C in the presence of a hydrogen chloride acceptor (triethylamine) leads to the formation of N-organylthioaziridines . Compounds with R=n-C₅H₁₁, C₆H₅, o-O₂NC₆H₄ and C₆H₆CH₂ have been obtained by this method. and . have been synthesized analogously.The properties and IR spectra of these compounds have been studied. The action of methyl iodide on N-phenylthioaziridine leads to disproportionation of the molecule with the formation of diphenyl disulfide, -iodoethyltrimethylammonium iodide, and free iodine.For communication VI, see [I].     

Synthesis of Fullerene-Containing Sol-Gel Glasses

Macroscopically homogeneous and visually transparent fullerene-containing glasses are fabricated from sol-gel mixtures of aminated C₆₀ derivatives and tetraethyl orthosilicate (TEOS) through physical blending and chemical reaction. The aminated fullerenes are synthesized by the amination reactions of C₆₀ with 6-amino-1-hexanol, cyclohexylamine, 2-(2-aminoethoxy)ethanol, and 3-aminopropyltriethoxysilane at 100°C under nitrogen. The amination products are purified by filtration, precipitation, and column chromatography and are isolated in good to excellent yields (32–82%). Characterization by NMR, MS, and TGA analyses reveals that the aminated fullerenes possess molecular structures H _x C₆₀[NH(CH₂)₆OH] _x , H _x C₆₀(NH-cyclo-C₆H₁₁) _x , H _x C₆₀[NH(CH₂CH₂O)₂H] _x , and H _x C₆₀[NH(CH₂)₃Si(OCH₂CH₃)₃] _x . All the aminated fullerenes except 2 are completely soluble in aqueous alcoholic solutions of TEOS and can be incorporated into silica gel networks by sol-gel process in the absence or presence of drying-control chemical additives, giving crack-free monoliths of large sizes (up to 60 mm). Electronic absorption spectrum of the fullerene glass continuously red shifts with an increase in the C₆₀ content, suggesting the formation of fullerene nanoclusters in the sol-gel process. The fullerene glasses are thermally and optically stable, resisting continuous attack of strong laser pulses of 532 nm for a prolonged period of time without losing their optical limiting power.     

Neutral counterparts of the C2H7O+ isomers

The neutral counterparts of the C₂H₇O⁺ isomers CH₃O⁺ (H)CH₃, CH₃CH₂OH₂⁺ and $ {\rm C}_2 \,{\rm H}_4 \,\, \cdot \cdot \cdot \mathop {\rm H}\limits^ + \, \cdot \cdot \cdot {\rm OH}_2 $ were studied by neutralization-reionization mass spectrometry. Protonated dimethyl ether and its —O(D)⁺ analogue were produced by protonation (deuteration) of dimethyl ether and also generated as a fragment ion from (labeled) ionized CH₃OCH₂CH(OH)CH₃ by loss of CH₃CO?. It was observed that the dissociation characteristics of the ions and the stability of their neutral counterpart depended on the internal energy of the protonated ether ions. Stable neutral CH₃?(H)CH₃ was only produced from energy-rich ions. The classical protonated ethanol ion CH₃CH₂OH₂⁺ (a) was produced at threshold by the loss of CH₃CO?. from ionized butane-2,3-diol. Mixtures of a with the non-classical ion $ {\rm C}_2 \,{\rm H}_4 \,\, \cdot \cdot \cdot \mathop {\rm H}\limits^ + \, \cdot \cdot \cdot {\rm OH}_2 $ (b) were produced by reaction of C₂H₅⁺ ions with H₂O. As for the protonated ether, only high-energy a and/or b ions yielded stable hypervalent radicals. It is suggested that the stable C₂H₇?O radicals are Rydberg states.     

Methylene radical cation transfer from ionized oxirane to CH3SCH3 and C6H5SCH3 in the gas phase: Formation of sulphur distonic ions and/or insertion in a carbon–sulphur bond

The α-distonic sulphur-containing ion $ {}^ \cdot {\rm CH}_2 \mathop {\rm S}\limits^ + \left({{\rm CH}_3 } \right)_2 $ has been generated by transfer of CH from ionized oxirane to dimethyl thioether and distinguished from the molecular ion of ethyl methyl thioether by collision induced dissociation (CID) experiments. In particular, the α-distonic ion expels CH₂ to a minor extent following collision, whereas the molecular ion of ethyl methyl thioether does not undergo this reaction. The metastable C₃H₈S^+˙ ions formed by CH transfer to dimethyl thioether and ionization of ethyl methyl thioether decompose by competing losses of CH₃R˙, CH₄ and C₂H₄. The elimination of ethene is taken as evidence for isomerization of the α-distonic ion to the molecular ion of ethyl methyl thioether prior to spontaneous dissociation. Evidence for the formation of stable α-distonic sulphur-containing ions by transfer of CH from ionized oxirane to methyl phenyl thioether has not been obtained. The collision-induced and spontaneous reactions of the ions formed by CH transfer to methyl phenyl thioether indicate that a mixture of the radical cations of CH₃C₆H₄SCH₃, C₆H₅SCH₂CH₃ and C₆H₅CH₂SCH₃ is generated implying that attack on the phenyl group occurs in addition to a formal insertion of a methylene entity in a C? S bond.     

Synthesis and properties of polyamides and polyamidoesters based on bis-[N-alkyl-(or aryl-)aminomethyl]-phosphonic acids

Conclusions The activity of bis-[N-alkyl-(or aryl)-aminomethyl] phosphonic acids of the general formula (RNHCH₂)₂ in the interfacial polycondensation reaction with bisphenol A has been studied.In their activity the diamines studied can be placed in the following series: R=C₆H₅CH₂, C₄H₉, C₆H₅, C₃H₇.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 633–636, March, 1969.     

Influence of solvents on the parameters of the NMR spectra of Vinca alkaloids. V

Summary On the basis of the results of a study of the influence of various solvents on the parameters of the NMR spectra of some hydroxyindole alkaloids, the following characteristic values of for the protons have been found:a) for C₁₉-CH₃ in the allo bases is +0.18 ppm; b) in the epiallo bases it is +0.36 ppm; c) for CO₂CH₃ in the allo bases is +0.30 to +0.37 ppm; d) in the epiallo bases it is +0.19 ppm; and e) for the 11-OCH₃ group in the hydroxyindoles is +0.44 to +0.52 ppm.It has been established that in the epiallo bases benzene causes a diamagnetic shift, and in the allo bases a paramagnetic shift, of the H₁₉ signal. It is possible to perform a stereochemical identification of the hydroxyindole alkaloids on the basis of the value of for C₁₉-CH₃, CO₂CH₃, and H₁₉ protons.Analysis of the signals of the aromatic protons of vineridine in C₆D₆ solution and in a number of other solvents has permitted their assignments to be refined and a long-range (allyl) coupling of the H₁₇ and H₁₅ protons with an SSCC of 2.0 Hz that is characteristic of the epiallo alkaloids to be found. It has been shown that the change in the CSs of the protons of rings D and E of the hydroxyindole alkaloids and the indole alkaloid reserpinine as a result of the influence of various solvents mainly has a symbatic nature. The invariability of the SSCCs of the protons in the solvents investigated with the exception of solutions in TFA, shows that the conformations of rings C, D, and E in them do not change. The changes in the CSs and SSCCs of the protons in the alkaloids investigated in TFA are an indication of the isomerization of these compounds in the acid.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 360–368, May–June, 1977.     

Unimolecular reactions of isolated organic ions: The chemistry of the unsaturated oxonium ion \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm CH}_{\rm 2} = {\rm CHCH =}\mathop {{\rm OCH}_{\rm 3}}\limits^{\rm +} $\end{document}

The reactions of metastable $ {\rm CH}_{\rm 2} = {\rm CHCH =}\mathop {{\rm OCH}_{\rm 3}}\limits^{\rm +} $ oxonium ions generated by alkyl radical loss from ionized allylic alkenyl methyl ethers are reported and discussed. Three main reactions occur, corresponding to expulsion of H₂O, C₂H₄/CO and CH₂O. There is also a very minor amount of C₃H₆ elimination. The mechanisms of these processes have been probed by ²H- and ¹³C-labelling experiments. Special attention is given to the influence of isotope effects on the kinetic energy release accompanying loss of formaldehyde from ²H-labelled analogues of $ {\rm CH}_{\rm 2} = {\rm CHCH =}\mathop {{\rm OCH}_{\rm 3}}\limits^{\rm + } $. Suggestions for interpreting these reactions in terms of routes involving ion–neutral complexes are put forward.     

Mass-spectrometric determination of the 4-center configuration in trans-linked 1,4-dialkyldecahydroquinolol-4′s

Conclusions By studying molecular ion stabilities and values of the ratio (the [M-C₂H₅]⁺ results from 4-C₂H₅ group elimination), we have been led to 4-center configurations for the trans-linked 1-alkyl-4-ethyl(ethynyl)decahydroquinolol-4s (Alk=CH₃, C₂H₅, n-and i-C₃H₇).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1524–1529, July, 1976.     

Reactivity of the Unsaturated Triosmium Cluster [Os3(CO)8{Ph2PCH2P(Ph)C6H4}(μ-H)] with Thiols

The reaction of the unsaturated cluster [(-H)Os₃(CO)₈{Ph₂PCH₂P(Ph)C₆H₄}] 2 with C₂H₅SH, CH₃CH(CH₃)SH and C₆H₅SH are reported. The reaction of 2 with C₂H₅SH yields the new complexes [Os₃(CO)₈(-SC₂H₅)(¹-SC₂H₅){Ph₂PCH₂P(Ph)C₆H₄}(-H)] 9 and [Os₃(CO)₈)(SC₂H₅)(Ph₂PCH₂P)(Ph)C₆H₄}] 8 in 24 and 57% yields respectively and the known compound [(Os₃(CO)₈)(-SC₂H₅)(-dppm)(-H)] 7 in 5% yield. Compound 9, which exists as two isomers in solution, converts into 8 almost quantitatively in solution at 25°C and more rapidly in refluxing hexane. Compound8 reacts with H₂ at 110°C to give 7 in high yield (86%). Treatment of 2 with propane-2-thiol yields [Os₃(CO)₈{-SCH(CH₃)CH₃}{Ph₂PCH₂P(Ph)C₆H₄}] 10 and [(Os₃(CO)₈{-SCH(CH₃)CH₃}{¹-SCH(CH₃)CH₃}{Ph₂PCH₂P(Ph)C₆H₄}(-H)] 11 in 75 and 3% yields respectively while with C₆H₅SH, [(Os₃(CO)₈(-SC₆H₅)(-dppm)(-H)] 6 is obtained as the only product in 75% yield. In both 8 and 10, the thiolato ligand bridges the Os–Os edge which is also bridged by the metallated phenyl group. The new compounds have been characterized by elemental analyses and spectroscopic methods (IR, ¹H and ³¹P NMR). The molecular structures of 7, 8, 9 and 10 are reported as determined by X-ray diffraction studies.     

Zur Kenntnis der Organophosphorverbindungen. XV. Darstellung und Reaktionen von Trimethylsilylestern der Phosphinsäuren

On Organophosphorus Compounds. XV. Preparation and Reactions of Trimethylsilyl Esters of Phosphinic Acids Trimethylsilylesters of Phosphinic acids R₂P(X)YSi(CH₃)₃ (R ? CH₃, C₂H₅, C₃H₇, t?C₄H₉, C₆H₅; X, Y ? O, S) were prepared by 7 different methods as in some cases easily hydrolysable but thermally remarkably stable compounds. The properties and some reactions of these substances are reported, their structures confirmed by IR? as well as ¹H- and ³¹P-NMR-spectroscopy. Dimethylsilylen-bis(phosphinic acid esters) were obtained according to \documentclass{article}\pagestyle{empty}\begin{document}$ 2{\rm R}_{2} {\rm P(\rm X)\rm ONH}_{4} + {\rm R}_{\rm 2} {\rm SiCl}_{2} \to 2{\rm E NH}_{4} {\rm Cl + R}_{2} {\rm P(X) - O - SiR}_{2} - {\rm O - P(X)R}_{2} ({\rm R = CH}_{3};{\rm X = O,S}) $\end{document}.     

Radiolysis of p-benzoquinone solutions

The products of the continuous radiolysis of p-benzoquinone (Q) at different concentrations of H₂SO₄, Q and Cl^– are p-hydroquinone (H₂Q) and 2-hydroxy-p-benzoquinone (2-Q-OH). In the presence of some alcohols, a carbonyl compound is produced in addition to H₂Q and 2-Q-OH. The dependence of G values of the products on these factors is described. The material balance between G(-Q) and G(H₂Q)+G(2-Q-OH) is maintained. The experimental results indicate the occurrence of the following reaction: . By competition studies, it was possible to evaluate the rate coefficients for the following reactions: .     

Reactions of alkoxy and hydroxy radicals generated photochemically from hydroperoxide molecules

In the present work as well as HRO^. radicals were generated in the photochemical interaction of 1,2-benzanthracene with -ethyl phenyl hydroperoxide /HROOH/ in C₆H₆ and CCl₄ at 304 K. radicals were trapped by C₆H₆. The main reaction of HRO^. radicals is hydrogen abstraction from the hydroperoxide group of HROOH. Although OH radicals are less selective, the hydrogen abstraction is the main process during their interaction with aromatics in contrast to reactions in aqueous solutions, where addition to the benzene ring is the rate-determining process in CCl₄:

Decomposition kinetics of ozone complexes with toluene and its deuterated derivatives

Decomposition rate of O₃ complexes with aromatic hydrocarbons (ArX·O₃) in ArXO₃-ArX-CH₂Cl₂ system (ArX=C₆H₅CH₃, C₆H₅CD₃ and C₆D₅CD₃) is described by the equation:

Phosphine free diamino-diol based palladium catalysts and their application in Suzuki-Miyaura cross-coupling reactions

Inexpensive air and moisture stable diamino-diol ligands [(2-OH-C₁₀H₆)CH₂(μ-NC₄H₈N)CH₂(C₁₀H₆-2-OH)] (1) and [(5-^tBuC₆H₃-2-OH)CH₂(μ-NC₄H₈N)CH₂(5-^tBuC₆H₃-2-OH)] (2) were synthesized by reacting corresponding alcohols with formaldehyde and piperazine. Treatment of ligands 1 and 2 with Pd(OAc)₂ in 1:1 molar ratio afforded neutral palladium complexes [Pd{(OC₁₀H₆)CH₂(μ-NC₄H₈N)CH₂(C₁₀H₆O)}] (3) and [Pd{(5-^tBuC₆H₃-2-O)CH₂(μ-NC₄H₈N)CH₂(5-^tBuC₆H₃-2-O)}] (4) in good yield. The palladium complexes 3 and 4 are employed in Suzuki-Miyaura cross-coupling reactions between phenylboronic acid and several aryl chlorides or bromides. They are found to be competent homogeneous catalysts for a variety of substrates to afford the coupled products in good to excellent yields. The crystal structures of compounds 2 and 4 are also reported.     

Phytoecdysones ofSilene praemixta. II. Premixisterone

The structure of premixisterone (I) — a new ecdysteroid fromS. praemixta M. Pop. (Caryophyllaceae) — has been established. Compound (I) has the composition C₂₇H₄₄O₅, mp 110–112°C (from C₂H₅OH + H₂O), [] _D ²⁴ 0 ± 4° (c 0.85; MeOH), 202 nm (log 3.35), _max ^KBr 3415 cm^–1 (OH), 1710 cm^–1 (C=0), and does not contain the ⁷-6-keto grouping that is characteristic of natural ecdysteroids. The acetylation of (I) with (CH₃CO)₂ in Py gave the amorphous 3,22-diacetylpremixisterone (II), C₂₁H₄₈O₇. Compound (I) has the structure of 3,14,22R,25-tetrahydroxy-5-cholest-8-en-6-one. The IR, PMR, and mass spectra of (I) and (II) are given.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 797–799, November–December, 1979.     

Quantum-Chemical Study of Anisole Molecule

The potential functions of internal rotation around the C -O bond in the C₆H₅OCH₃ molecule were obtained by HF/6-31G(d), MP2(f)/6-31G(d), and B3LYP/6-31(d) calculations. Hartree-Fock calculations reveal a fourfold barrier to internal rotation around the C -O bond. The MP2 and B3LYP calculations reveal a twofold barrier with a height of 7.78 and 10.70 kJ mol^{- 1}, respectively (corrected for the zero vibration energy). The molecular geometries, first Koopmans ionization potentials, and dipole moments are reported. Calculations for liquid anisole in the self-consistent reactive field (SCRF) continual model give the results that only slightly differ from the results obtained for the isolated molecule in a vacuum. Within the framework of the Natural Bond Orbitals formalism, the following parameters were determined: energy, degree of hybridization, and population of oxygen lone electron pairs and energy of their interaction with antibonding ^* orbitals of the aromatic ring.     

The collisionally induced dissociation of allyl and 2-propenyl cations

Pure [CH₂CHCH₂]⁺ and \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm{CH}}_{\rm{3}} \mathop {\rm{C}}\limits^{\rm{ + }} = {\rm{CH}}_{\rm{2}} $\end{document} ions are generated only in metastable fragmentations of [CH₂?CHCH₂X]⁺˙, X=Cl, Br, I, and [CH₃CX?CH₂]⁺˙, X=Br, I, respectively. For ion source generated [C₃H₅]⁺ ions there is some structural interconversion. The structure characteristic feature of their collisional activation mass spectra is the ratio m/z 27 ([C₂H₃]⁺): m/z 26 ([C₂H₂]⁺˙). For \documentclass{article}\pagestyle{empty}\begin{document}$ {\rm{CH}}_{\rm{3}} \mathop {\rm{C}}\limits^{\rm{ + }} = {\rm{CH}}_{\rm{2}} $\end{document} the ratio is only weakly dependent upon the translational energy of the ion. For [CH₂CHCH₂]⁺, the ratio rises sharply as translational energy is reduced, from 0.9 at 8 kV to c. 3 at 1 kV. [CH₂CHCH₂]⁺ ions generated by charge reversal of [CH₂CHCH₂]^? show higher ratios, resulting from their lower average internal energy content. It must therefore be emphasized that [C₃H₅]⁺ ion structure assignments should only be made using reference data which apply to specific experimental conditions. [C₃H₅]⁺ daughter ion structures for a number of well-known fragmentations have been established. The heat of formation of the 2-propenyl cation was measured to be 969±5 kJ mol^?1. Labelling experiments show that at low internal energies, allyl cations do not undergo atom randomization in c. 1–2 μs; high internal energy ions of longer lifetime (c. 8 μs) show complete atom randomization. H^˙ atom loss from [¹³CH₃CH?CH₂]⁺˙ has been shown to generate [¹³CH₂CHCH₂]⁺ and \documentclass{article}\pagestyle{empty}\begin{document}$ {}^{{\rm{13}}}{\rm{CH}}_{\rm{2}} \mathop {\rm{C}}\limits^{\rm{ + }} - {\rm{CH}}_{\rm{3}} $\end{document} without any skeletal rearrangement.