Reactions ofN-pentafluorophenylcarbonimidoyl dichloride with aromatic hydrocarbons in the presence of aluminum chloride

N-Pentafluorophenylcarbonimidoyl dichloride reacts with aromatic hydrocarbons (benzene, toluene, xylenes, and mesitylene) in the presence of AlCl₃ to give stableN-pentafluorophenylbenzimidoyl chlorides, which can further react with aromatic hydrocarbons to give azomethine derivatives. An increase in the number of methyl groups in the molecule of a hydrocarbon favors the reaction.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1605–1611, September, 1993.     

Reactions of stannyl carbamates with organochlorosilanes

Rapid and exothermic reactions of stannyl carbamates with organochlorosilanes result in cleavage of the Sn-O-C bond and afford silyl carbamates in a high yield.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 313–314, February, 1994.     

Reactions of cage metal siloxanes with functionalized organochlorosilanes

The reactions of [(2-acetoxyetoxy)methyl]dimethylchlorosilane and 1-acetoxy-2-(dimethylchlorosilylmethoxy)benzene with the cage phenylcopper and phenylmanganese siloxanes leads to the cleavage of the M—O—Si bond to give metal chlorides and six-unit cyclosiloxanes with an acetoxy group in the organic substituent at the silicon atom. Methanolysis of these acetoxy derivatives does not affect the ring structure and affords the corresponding polyhydric alcohols.     

Reactions of arylacetylenic compounds with arenes in the presence of aluminum halides

Conjugated arylacetylenic ketones and aldehydes, propargyl-type alcohols, and arylacetylenes reacted with arenes in the presence of AlBr₃ or AlCl₃ as catalyst to give substituted indenes. 3-Arylpropynoic acids under analogous conditions gave rise to 3,3-diarylindan-1-ones, while the corresponding methyl esters were converted into methyl 3,3-diarylprop-2-enoates. The key intermediates in the transformations of acetylenic ketones and aldehydes and propargyl-type alcohols into indene derivatives are resonance-stabilized propargyl—allenyl cations -C≡ C-C⁺ ? -C⁺=C=C which reacted with one of the resonance structures to give isomeric indenes, depending on the substituent nature.     

Reactions of oxalyl chloride with 1,2-cycloalkanediols in the presence of triethylamine

The relationship between the product patterns and the configurations of 1,2-cycloheptane- and 1,2-cyclooctanediols 9 in the cyclocondensations with oxalyl chloride in the presence of triethylamine at 0 degrees C has been shown analogous to that obtained for 1,2-disubstituted acyclic ethylene glycols 1: cis-1,2-cyclooctanediol (9f) produced the cyclic oxalate 14f as the major product, while trans-1,2-cycloheptanediol (9e) and trans-1,2-cyclooctanediol (9g) formed the cyclic carbonates 12e, g as the major products. On the other hand, the cyclic oxalates 14a-d were formed as the major products from 1,2-cyclopentane- and 1,2-cyclohexanediols regardless of the configuration. These results can be accounted for by assuming the boat-like transition states for cyclizations of the half esters of comparatively rigid five- and six-membered diols 9a--d. The cyclic oxalates 14a, c may be directly formed through the resulting tetrahedral intermediates from cis-diols (9a,c), and the cyclic carbonates 12a,c as the minor products after ring inversion of the tetrahedral intermediates. The tetrahedral intermediates from the trans-isomers 9b, d cannot undergo ring inversion, producing no traces of the cyclic carbonates 12b, d.     

Free-Radical copolymerization of N-vinylsuccinimide with butyl acrylate in the presence of zinc chloride and aluminum chloride

The free-radical copolymerization of N-vinylsuccinimide with butyl acrylate performed in dimethyl sulfoxide and benzyl alcohol in the presence of zinc chloride and aluminum chloride as complexing agents is studied. Under the given conditions, the reactivity ratios are determined. It is shown that zinc chloride influences the electron-density distribution only in butyl acrylate molecules. It is found that benzyl alcohol retards the total rate of polymerization. The character of the monomer-unit distribution in copolymer macromolecules is described.     

Functionalization of syndiotactic polystyrene with succinic anhydride in the presence of aluminum chloride

Syndiotactic polystyrene has been chemically modified with succinic anhydride by use of Friedel-Crafts acylation reaction in the presence of anhydrous aluminum chloride in carbon disulfide. The modified syndiotactic polystyrene containing -COCH₂CH₂COOH fragments in side phenyl rings, named succinoylated syndiotactic polystyrene (s-sPS), was characterized by FTIR and ¹H NMR spectroscopy. The effects of reaction conditions on the degree of succinoylation of s-sPS were investigated. In addition, the effects of incorporation of carboxyl groups into syndiotactic polystyrene on the thermal behavior were studied by differential scanning calorimetry in comparison with pure syndiotactic polystyrene. It was found that the crystallization temperature, melting temperature, and degree of crystallinity of the modified polymer decreased with increasing the degree of succinoylation, while the glass transition temperature increased.     

Bromination of 2-benzoylthiophene in the presence of excess aluminum chloride

Russian Chemical Bulletin -     

Ligand exchange reactions of ferrocene with phenanthrene or 9,10-dimethylphenanthrene in the presence of aluminum chloride and aluminum

Ligand exchange reactions between phenanthrene or 9,10-dimethylphenanthrene with ferrocene effected in the presence of AlCl₃-Al were carried out under a variety of conditions. With phenanthrene (I), hydrogenation at the C-9 and C-10 positions could take place during the reaction and the cationic products obtained were the η⁶-phenanthrene-η⁵-cyclopentadienyliron and η⁶-9,10-dihydro-phenanthrene-η⁵-cyclopentadienyliron moncations (II and III), and the η⁶-phenanthrene-$\text{trans}$-$\text{bis}$-η⁵-cyclopentadienyliron and η⁶-9,10-dihydrophenanthrene-$\text{trans}$-$\text{bis}$-η⁵-cyclopentadienyliron dications (IV and V). With 9,10-dimethylphenanthrene (VI), reactions carried out in refluxing cyclohexane gave the non-hydrogenated η⁶-9,10-dimethylphenanthrene-η⁵-cyclopentadienyliron monocation (VII) and η⁶-9,10-dimethylphenanthrene-$\text{trans}$-$\text{bis}$-η⁵-cyclopentadienyliron dication (VIII). When higher temperatures were used in an attempt to promote hydrogenation, decomposition predominated and no cationic product could be obtained. These finding are discussed and contrasted with previous results obtained from similar reactions using anthracene or 9,10-dimethylanthracene.     

Spectrofluorimetric determination of thallium in silicate rocks with rhodamine b in the presence of aluminum chloride

A sensitive spectrofluorimetric procedure with rhodamine B in the presence of aluminum chloride is given for determining submicrogram and microgram quantities of thallium in silicate rocks. Samples are decomposed with a mixture of hydrofluoric and nitric acids and then treated with hydrochloric acid. Thallium is extracted as its dithizonate with chloroform from an alkaline medium containing ascorbate, citrate, and cyanide and then back-extracted with dilute nitric acid. After destruction of the organic matter and treatment with bromine, hydrochloric acid, aluminum chloride, and rhodamine B, the

T001. Determination of thallium in U.S. Geological Survey standard rocks by different laboratories

Thallium (p.p.m.)		Method	Ref.
G-1	W-1
1.06	0.102	Neutron activation analysis	1
1.08	0.121, 0.116	Neutron activation analysis	2
1.3	0.17	Neutron activation analysis	3
1.3	0.11	Spectrographic	4
	0.105–0.110	Flameless atomic absorption spectroscopy	5
1.3a	0.13a		19
1.24b	0.110b		20
1.09 ± 0.01	0.110 ± 0.005	Spectrofluorimetric	Present method

a

Values given by Fleischer.

b

Average value given by Flanagan. fluorescence intensity of the benzene-extracted rhodamine B chlorothallate is measured. The limit of determination is approximately 0.01 p.p.m. for a 1.0-g sample. The thallium contents of U.S. Geological Survey standard rocks G-1 and W-1 were found to be 1.09 ± 0.01 and 0.110 ± 0.005 p.p.m., respectively.

     

Transformation of 1,1,3,3-tetramethyl-1,3-disilacyclobutane in presence of aluminum chloride

Conclusions The reaction of equimolar amounts of 1,1,3,3-tetramethyl-1,3-disilacyclobutane and aluminum chloride gives tetramethylsilane and a mixture of linear and cyclic silmethylene compounds.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 953–955, April, 1975.     

Mathematical modeling of the catalytic degradation of polystyrene in the presence of aluminum chloride

We model the effect of the catalyst AlCl₃ on polystyrene (PS). Detailed experimental studies were previously carried out on the effect of AlCl₃ on PS, as part of an effort to understand how to minimize the degradation of PS during the Friedel-Crafts alkylation performed to obtain a graft copolymer from immiscible blends of PS and a polyolefin (PO). In the present work three mathematical models for the catalytic degradation of PS are proposed, all of which consider that reaction starts with the elimination of a phenyl group from the PS chain, followed by either chain scission or a change in the chain structure. The models vary in the way they consider the strength of the main chain bonds, or the reactivity of modified PS chains. Kinetic parameters for each model are estimated. Although the three proposed models could be used to represent our own experimental data, one is more accurate. Experimental data from other authors are used to evaluate its capabilities. Based on the predictions of the better model, we discuss conditions to minimize PS scission, such as operating at low temperatures and AlCl₃ concentrations, and using short processing times.     

Action of bromine and tert-butyl chloride on methyl-2-furyl ketone in the presence of excess aluminum chloride

Summary Methyl 2-furyl ketone is brominated in the nucleus in the presence of 3 moles of aluminum chloride without solvent.