Suzuki cross-coupling reaction of fluorobenzene with heterogeneous palladium catalysts

In this work, we accomplished for the first time the Suzuki cross-coupling reaction between fluorobenzene and phenylboronic acid with different heterogeneous catalysts and bases. The conversion values obtained are similar to those provided by homogeneous catalysts and activated aryl fluorides.     

Kinetics of the reaction of solvated electrons with fluorobenzene in liquid ammonia

The rate of disappearance of solvated electrons by reaction with fluorobenzene in ammonia is accelerated by small concentrations of methanol; it also has a “negative activation energy” depending on the methanol concentration. The kinetic data suggest an exothermic electron attachment-detachment equilibrium with the fluorobenzene followed by a slower reaction of the electron adduct with the proton donating methanol.     

Homolytic reactions of polyfluoroaromatic compounds V. The reaction of pentafluorophenyl radicals with fluorobenzene

The arylation of fluorobenzene with pentafluorophenyl radicals obtained by the reaction of the corresponding aniline with pentyl nitrite is described. The reaction involves attact at the 2t?-,3t?-and 4t?-positions. The composition of the mixture and the nature of its components were determined by ¹⁹F NMR spectroscopy and were confirmed by gas-liquid chromatography.     

Photodissociation dynamics of fluorobenzene

Photodissociation of both fluorobenzene and d(5)-fluorobenzene at 193 nm under collision-free conditions has been studied in separate experiments using multimass ion imaging techniques. HF and DF eliminations were found to be the major dissociation channels. Small amounts of photofragments, C(6)H(4)F and C(6)D(4)F, corresponding to H and D atom eliminations were also observed. Dissociation rate and fragment translational energy distribution suggest that HF (DF) and H (D) atom elimination reactions occur in the ground electronic state. The potential energy surface obtained from ab initio calculations indicates that the four-center reaction in the ground electronic state is the major dissociation mechanism for the HF and DF eliminations. A comparison with photodissociation of benzene has been made.     

Low-temperature dehalogenation of benzyl halides with atomic magnesium in the3P state

Low-temperature reactions of benzyl halides with magnesium in the³P state proceed according to the radical mechanism accompanied by abstraction of the halogen atom by the biradical magnesium atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 147–151, January, 1999.     

Photochemical reaction of magnesium tetraphenyl porphyrin with sulfur dioxide

<正>The photochemical reaction of magnesium tetraphenyl porphyrin(MgTPP) with sulfur dioxide(SO_2) was investigated in dichloromethane(CH_2Cl_2) by steady-state fluorescence,UV-vis absorption,MS,and XRD spectroscopic techniques.These spectra showed that under irradiation MgTPP reacted with SO_2 to form 1:1 molecular adduct at first step.During the process of keeping irradiation and maintaining the flow of SO_2,SO_2 was reduced into S~(2-) by MgTPP and the results were detected using MS and XRD techniques.Understanding the photochemical reaction of MgTPP with SO_2 is of key interest in elucidating fundamental photochemical reaction mechanisms associated with this class of chlorophyll in the presence of SO_2.     

Study of the reaction of polyester resins with magnesium oxide

The reaction of polyester resin and magnesium oxide, which is the basis of the thickening process of sheet-molding compound technology, has been characterized in a systematic study. The effect of reactant equivalency ratios, temperature, and added water on viscosity development have been determined. Excess amounts of magnesium oxide are necessary for thickening. Water increases the initial rate of thickening but reduces the overall level attained. A new thickening mechanism is proposed on the basis of a model study with polyester resin and sodium hydroxide.     

Novel palladium complex-catalyzed reaction of magnesium amides with allylic electrophiles

Conclusions A novel method has been described for the efficient formation of nitrogen-carbon bonds via the reaction of magnesium amides with functionalized nitrogen, oxygen, and sulfur-containing allylic derivatives, catalyzed by transition metal complexes. New high (molecular weight) unsaturated tertiary amines have been prepared.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 406–409, February, 1987.     

Selenophilic reaction of organolithium and magnesium reagents with phosphinoselenoic chlorides

The reaction of phosphinoselenoic chlorides 1 with various organolithium and magnesium reagents was studied. Sequential reaction of phosphinoselenoic chlorides 1 with organolithium and magnesium reagents and elemental selenium gave two types of products, phosphine selenides 2 and phosphinodiselenoic acid esters 3 . The esters 3 appeared to be formed via the selenophilic reaction of organolithium and magnesium reagents with the chlorides 1 . Molecular orbital calculations were carried out for model compounds H₂P(E)Cl (E = O, S and Se) to determine their electronic structures. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:185–191, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20091     

Low-temperature branching ratios for the reaction of state-prepared N2(+) with acetonitrile

In this work, the primary product branching ratio (BR) for the reaction of state-prepared nitrogen cation (N(2)(+)) with acetonitrile (CH(3)CN), a possible minor constituent of Titan's upper atmosphere, is reported. The ion-molecule reaction occurs in the collision region of the supersonic nozzle expansion that is characterized by a rotational temperature of 45 ± 5 K. A BR of 0.86 ± 0.01/0.14 ± 0.01 is obtained for the formation CH(2)CN(+) and the CH(3)CN(+) product ions, respectively. The reported BR overwhelmingly favors the formation of CH(2)CN(+) product channel and is consistent with a simple capture process that is accompanied by a nonresonant dissociative charge transfer reaction. The BRs are independent of the N(2) rotational levels excited. Apart from providing insights onto the dynamics of the title ion-molecule reaction, the reported BR represents the most accurate available low-temperature experimental measurement for the reaction useful to aid in the accurate modeling of Titan's nitrile chemistry.     

Catalytic asymmetric aza-Darzens reaction with a vaulted biphenanthrol magnesium phosphate salt

Conditions for a catalytic asymmetric aza-Darzens aziridine synthesis mediated by a vaulted biphenanthrol (VAPOL) magnesium phosphate salt is described. Using simple substrates, this methodology explores the scope and reactivity of a new magnesium catalyst for an aziridination reaction capable of building chirality and complexity simultaneously.     

Identification of intermediates in the reaction of 2-thenyl halides with magnesium

The reaction of 2-thenyl chloride with magnesium was shown by the ESR method to proceedvia the intermediate formation of radicals and radical ion pairs, whereas similar reactions of 2-thenyl bromide and iodide occur through the formation of free radicals only. Published inIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1556–1559, September, 2000.     

Catalytic oxidation of fluorobenzene by molecular oxygen

Kinetic and thermal-desorption methods have been applied to the oxidation of fluorobenzene by molecular oxygen. The catalytic oxidation mechanism for fluorobenzene is similar to that for benzene. A suggestion is made on why there is no fluoromaleic anhydride in the oxidation products from fluorobenzene.Translated from, Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 1, pp. 116–119, January–February, 1989.     

Theoretical studies of electrophilic substitutions in fluorobenzene

Results from an ab initio MO LCAO SCF study of the electronic structure of fluorobenzene are reported. A minimal basis set of contracted gaussian functions has been used to calculate the electrostatic molecular potential. The obtained isopotential maps indicate that fluorine has a para-directing effect in accordance with chemical evidence.     

Preparation of anhydrous magnesium chloride in a gas-solid reaction with ammonium carnallite

Dehydrated ammonium carnallite was synthesized with bischofite from salt lake and ammonium chloride solution in a 1:1 molar ratio of MgCl₂:NH₄Cl, dehydrated at 160°C for about 4 h. The yield was above 85%. The product was then mixed with solid-state ammonium chloride with a 1:4 mass ratio for the further dehydration at 410°C. The decomposition of NH₄Cl made a pressure of NH₃ at 30.5 kPa to prevent the hydrolysis of ammonium carnallite. The anhydration of magnesium chloride was achieved at 700°C. The results showed that anhydrous magnesium chloride contains magnesium oxide in an amount that was less than 0.1% by weight. XRD pattern and SEM micrograph showed a good dispersion of ammonium carnallite and anhydrous magnesium chloride crystals with well-distributed big grains, just enough to meet the need for the production of magnesium metal in the electrolysis process. __________ Translated from Chinese Journal of Applied Chemistry, 2005, 22(8) (in Chinese)     

Kinetic model for reaction of aspartic acid with magnesium carbonate in solution

A kinetic model has been developed for describing the non-catalytic liquid-solid reaction between aspartic acid and magnesium carbonate in solution, with parallel dissolution of aspartic acid particles. The effects of size distribution of both the aspartic acid and magnesium carbonate particles have been accounted for by using a population balance model. The parameters of the model have been estimated by fitting them to experimental data taken from literature.

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二茂镁的原位合成及其与羰基化合物的反应

研究了通过萘锂还原法制得的活性镁与环戊二烯原位合成环戊二烯基镁(Cp~2Mg)的方法。Cp~2Mg的存在是由它与醛酮反应生成富烯得到证实。此法产率高, 方法简单, 条件温和。     

The structural transformations of silicon phthalocyanine in reaction with magnesium and trimethylchlorosilane

The reaction of PcSi(OSiMe₃)₂ with Mg in the presence of Me₃SiCl at 20–100°C was shown to cause the phthalocyamine macrocycle contraction and give the silicon α,β,γ-triazatetrabenzocorrole macrocycle. The reaction proceeds in the polar donor solvents (THF, pyridine), but does not occur in aromatic hydrocarbons. The electronic and EPR spectra indicate that the silicon phthalocyanine mono- and dianions are active intermediate reaction products.