Alkyl Benzyl Research Articles

Orthopalladation of chelating aromatic compounds

Aromatic substrates possessing either nitrogen or sulfur ligands meta to one another have been found to undergo regiospecific orthometallation with lithium tetrachloropalladate. In some cases, this metallation has been found to be catalyzed by silica gel. This is the first report of the palladation of a phenethyl amine or a benzyl alkyl sulfide.

Studies of Unusual Amino Acids and Their Peptides. XII. The Chemistry of N-(Carboxymethyl)amino Acids. I. The Preparation, Properties, and Characterization of N-(Carboxymethyl)amino Acids and Their Esters

Abstract N-Carboxymethyl(Cm-)amino acids and their mono- and diesters were prepared by several routes, and their physical and chiroptical properties were compared with those of the parent amino acids and their esters. The isolation procedure was improved for the preparation of the free Cm-amino acids obtained from the corresponding amino acids and bromoacetic acid; the aimed-at compounds were also obtained by the catalytic hydrogenolysis of the dibenzyl esters. The isomeric pairs of monoalkyl esters of Cm-amino acids were similarly accessible via the benzyl alkyl esters. The diesters proved to be suitable for the GLC and MS analyses of Cm-amino acids. All the free Cm-l-amino acids and the dicyclohexylammonium salts of their N-ethylthiocarbonothioyl derivatives show positive Cotton effects at 200–225 nm and at 335–350 nm respectively in CD measurements; therefore, these correlations can be used for the configurational assignments of Cm-amino acids.

Formation of C–S Bond by the Elimination of Perfluorocarboxylic Acid

Abstract Thiirane was readily generated from 2-mercaptoethyl trifluoroacetate or pentafluoropropionate by the intramolecular elimination of the perfluorocarboxylic acid with triethylamine. Alkyl benzyl sulfides were also prepared from benzyl trifluoroacetate or pentafluoropropionate and alkanethiols by the intermolecular elimination of the perfluorocarboxylic acid

Fluoride ion promoted synthesis of alkyl phenyl ethers

Tetraethylammonium fluoride in dimethylformamide promotes the alkylation of phenols with alkyl iodides and benzyl chloride to provide good yields of alkyl phenyl ethers. A number of phenols have been investigated including examples of sterically hindered phenols, phenols containing anion stabilising groups, and intramolecularly hydrogen bonded phenols, the majority of which react smoothly and efficiently in the fluoride system.

Strong base-catalyzed thermal rearrangements of azines of benzyl alkyl ketones

Azines of benzyl alkyl ketones undergo cyclization in the presence of strong basic catalysts to give mixtures of compounds of the pyrrole and pyrazole series. The formation of pyrazole products probably proceeds via the scheme of the Fischer reaction taking into account the concept of a [3,3] sigmatropic shift. However, the presence of nitriles and hydrocarbons among the products of the reaction of pyrazole derivatives indicates the ambiguous character of the proposed scheme. The rearrangement of azines to pyrazole compounds probably proceeds through a step involving the formation of a carbanion, while the formation of nitriles and hydrocarbons can be explained by radical processes. The dependence of the ratio of the pyrolysis products (pyrrole/pyrazole) on the amount of catalyst and its basicity (LiH, NaH, KH, NaOH, KOH, PhOK, and CH3OK) makes it possible to assume that the occurrence of the reaction through a step involving a [3,3] shift is realized thermally and that small amounts of the catalyst promote the realization of this reaction pathway; however, a high percentage of the catalyst and the use of the most basic catalysts lead to an increase in the yields of the pyrazole products.

Ultraviolet absorption spectra of alkyl benzyl sulphides. Conformational analysis of alkyl aryl sulphides

The u.v. spectra of a series of alkyl benzyl sulphides are consistent with the presence of a band which arises from mixed charge-transfer and locally excited states of very weakly π-conjugated sulphide and aryl groups. The u.v. spectra of alkyl aryl sulphides (including thioanisole) are consistent with the presence of one preferred conformation in which the alkylthio group is partially twisted out of plane of the aryl ring. p–π Overlap is sufficiently reduced to allow d-orbital participation to be detected.

Dielectric properties of yeast cells: Effect of some ionic detergents on the plasma membranes

Dielectric measurements were made on suspensions of yeast cells treated with two homologous series of sodium alkyl (C8, C10, C12, C14) sulfonates and alkyl (C8, C10, C12, C14, C16, C18) benzyl dimethyl ammonium chlorides over a frequency range of 10 kHz to 100 MHz. Dielectric dispersions observed for the suspensions of intact yeast cells are found to be reduced by treatment with these detergents, the reduction being accompanied by a decrease in packed volume of the cells and by a leakage of intracellular compounds. The reduction of dielectric dispersions is considered to be caused by a decrease in volume of the cells in suspensions and an increase in conductivity of the cell membranes. An effect of the alkyl chain length of the detergents on the reduction of dielectric dispersions is also examined for these ionic detergents. The reducing effect shows the maximum at the alkyl chain, C14 for sodium alkyl sulfonates and at C16 for alkyl benzyl dimethyl ammonium chlorides. These results are consistent with hemolysis and bactericidal activity.

ELECTROREDUCTIVE ACYLATION OF BENZYL CHLORIDE AND RELATED COMPOUNDS WITH ACID CHLORIDES

Abstract The electroreduction of benzyl chloride and related compounds in the presence of acid chlorides gave alkyl benzyl ketones in moderate yields. The controlled potential electrolysis suggests that the electron transfer from the cathode to benzyl chloride yielding an anionic species is the initiation step of this reductive acylation.

Synthesis of 1-phenyl-3-methyl-4-alkyl-4-[N-methylbutyro(capro)lactyl]-5-pyrazolones

The corresponding hydrazones, which on heating are cyclized to give 1-phenyl-3-methyl-4-alkyl-(benzyl)-4-(2-oxopyrrolidinomethyl)- and 1-phenyl-3-methyl-4-alkyl(benzyl)-4-(N-methylcaprolactyl)pyrazolones, are formed in the reaction of alkyl(benzyl) (2-oxopyrrolidinomethyl)- and alkyl-(benzyl) (N-methylcaprolactyl)acetoacetic esters with phenylhydrazine.

Dichotomous ylide formation from an alkyl(benzyl)phosphonium salt leading to stereoselective alkene syntheses

Condensation reactions between the tributyl-(4-methoxy-2,6-dimethylbenzyl)phosphonium salt (1b) and several aryl alkyl ketones, in the presence of methylsulphinylmethanide ion, are shown to lead to mixtures of stilbene and styrene products, resulting from dichotomous ylide formation. By contrast, with p-anisaldehyde, the salt (1b) produces solely the stilbene (10), and condensation between the tributyl-(4-methoxybenzyl)phosphonium salt (8) and 4′-methoxyacetophenone produces only the stilbene (9). The olefin-forming reactions between (1b) and aryl alkyl ketones are completely stereoselective, leading to Z-stilbenes [e.g.(3)] and E-styrenes [e.g.(6)]. Explanations for the stereoselectivities are discussed.

The induced decomposition of t-butyl peroxide in solution. Part III. Decomposition of t-butyl peroxide in alkyl benzyl ethers; steric effects

Product and rate studies of the thermal decomposition of t-butyl peroxide in a series of alkyl benzyl ethers PhCH2·OR (R = Me, Et, Pri, But, or Ph) show little induced decomposition of the peroxide by the ether radical PhĊHOR, whereas in the case of the chloro-substituted ethers ArCH2·OR (Ar = 4-ClC6H4 or 3,4-Cl2C6H3, R = Me, Et, Pri, But, or Ph) induced decomposition does occur to widely varying degrees, showing marked steric influence by the group R.

Substituent effects in the hydrogenolysis of benzyl alcohol derivatives over palladium

A kinetic study of substituent effects in the liquid-phase hydrogenolysis of benzyl oxygen compounds has been made using carbon-supported palladium as the catalyst. The reaction is zero order in substrate and is progressively inhibited by its product. Proton catalysis is essential for the hydrogenolysis of benzyl alcohols and alkyl benzyl ethers. For the hydrogenolysis of benzyl alcohols and 2-aryl-3-methyl-2-butanols the effects of substituents in the aromatic ring may be expressed in terms of a Hammett-Yukawa relationship with ϱ = −0.37 and −1.43, respectively. α-Substituents retard the rate of hydrogenolysis of benzyl alcohol. The order of reactivity for different leaving groups is: OH, OAlkyl ⪡ OAryl < +OHAlkyl < +OH 2, OAc < OCOCF 3. It is concluded that the hydrogenolysis reaction involves hydride attack at the benzylic carbon displacing the leaving group as its anion. For primary alcohols an S N2 mechanism is operative, whereas tertiary alcohols show s N1 type character. The adsorbed state is discussed on the basis of deuterolysis experiments.

2-Alkyl-3-phenylcinchoninic acids and related products

E i g h t 2-alkyl-3-phenylcinchoninic (2-alkyl-3-phenyl-4quinolinecarboxylic acid) acids were prepared by the interaction of the requisite alkyl benzyl ketone with isatin under Pfitzinger conditions ( 5 ) as modified by Henze and Carroll (4). The literature had shown that for the first two members of the series, the methyl and ethyl benzyl ketones, condensation takes place with the methylene adjacent to the phenyl rather than the methylene of the alkyl group (2). Each cinchoninic acid was decarboxylated to the quinoline and converted without isolation to its picrate derivative. Each 2-alkyl-3-phenylcinchoninic acid was converted into the corresponding 6-alkyl-1 l-indeno[l,2-c]quinolin-ll-one ( I ) , from which its oxime derivative was prepared. Table I lists the data on the 2-alkyl-3-phenylcinchoninic acids and the picrates. Table I1 lists the data on the 6-alkyl-11-indeno [1.2,-c ]quinolin-l 1 -ones and oximes.

Alkyl benzyl ketones and hydantoin derivatives

Alkyl benzyl ketones and hydantoin derivatives

502. 海水中のウランの採取,(III)

A study was made of foam separation with various kinds of surface active agents and adsorption separation with metallic soaps and lauryl amine salts, for the purpose of concentrating trace amounts of U in various kinds of salt solutions and sea water. The optimum conditions were influenced by the chemical components of the solutions. The most effective methods brought to light were as follows:(1) Foam separation with lauryl amine acetate on neutral solutions of various salts, alkyl benzyl ammonium chloride on weak alkali solution, and lauryl betain on acidic solution of nitrate and sea-water.(2) Adsorption of U contained in sea-water by Fe, Ti and Zn soaps. In acidified sea water, was adsorbed by Mg, Ti and Ni soaps.(3) Adsorption of U in chloride, sulfate and nitrate solutions by Ca soap. U in sea water was adsorbed only when acidified.(4) Adsorption of U in the various salt solutions by lauryl amine phosphate.

Steroidal sulphur compounds. Part V. Configuration, conformation, and chiroptical properties of steroidal benzyl sulphoxides

Steroidal C-3 and C-6 benzyl sulphoxides of (R)-configuration at sulphur displayed negative Cotton effects below 220 nm. and positive Cotton effects in the range 229–236 nm. in ethanol. The Cotton effects are of greater amplitude and occur at longer wavelengths than those of the corresponding methyl sulphoxides, in analogy with the relation between dialkyl and alkyl benzyl ketones. Changes in conformational equilibria were probably not important in solvent-induced variations in amplitudes of the Cotton effects. Pyrolysis of (R)-3α-benzylsulphinyl-5α-cholestane gave 5α-cholest-2-ene regiospecifically.

The photochemistry of 1,2,3-triphenylaziridine

Photochemical behaviour of 1,2,3-triphenylaziridine has been investigated. Irradiation in alcoholic solvents induces a novel type of alcoholytic cleavage of the aziridine ring to give benzaldehyde acetals and N-benzylaniline. Competitively, fragmentation occurs to give rise to benzalaniline and phenylcarbene, the latter being trapped with alcohols as alkyl benzyl ethers. Photolysis in cyclohexene affords a 1,3-cycloaddition product, 1,2,3-triphenyloctahydroisoindole as a mixture of two stereoisomers.

Mechanistic Aspects of the Rearrangement and Elimination Reactions of α-Metalated Benzyl Alkyl Ethers

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMechanistic Aspects of the Rearrangement and Elimination Reactions of α-Metalated Benzyl Alkyl EthersPeter T. Lansbury, V. A. Pattison, J. D. Sidler, and J. B. BieberCite this: J. Am. Chem. Soc. 1966, 88, 1, 78–84Publication Date (Print):January 1, 1966Publication History Published online1 May 2002Published inissue 1 January 1966https://doi.org/10.1021/ja00953a016RIGHTS & PERMISSIONSArticle Views427Altmetric-Citations77LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (871 KB) Get e-Alerts Get e-Alerts

The α-Bromobenzyl Alkyl Ether as an Intermediate in the Reaction of Benzyl Alkyl Ethers with Free-Radical Reagents

The α-Bromobenzyl Alkyl Ether as an Intermediate in the Reaction of Benzyl Alkyl Ethers with Free-Radical Reagents

Nitration of models of lignin containing benzyl alcohol and alkyl benzyl ether groupings

1. Models of lignin-α-ethylveratryl alcohol (II), its methyl ether (VI), andα-ethyl-4-hydroxy-3-methoxy-benzyl alcohol methyl ether (V)-were nitrated with concentrated HNO3 in CCl4 and in dry ether. 2. In the nitration ofα-ethyl-4-hydroxy-3-methoxybenzyl alcohol methyl ether (V) the side chain in the para position relative to the phenolic hydroxyl is replaced by the nitro group with formation of 4,6 -dinitroguaiacol. 3. In the nitration ofα-ethylveratryl alcohol methyl ether (VI) the main factor determining the course of reaction is the molar ratio of the substance being nitrated and HNO3. With a 1∶ 3 ratio the nitro group enters the 6-position of the aromatic nucleus, with a 1∶6 ratio nitration of the nucleus is accompanied by the replacement of the benzyl ether grouping by a nitric ester grouping, and at ratios of 1∶9 and 1∶12 there are two cmpeting reactions: replacement of the side chain by a nitro group and the formation of the mononitro compound nitrate (IV) in the first case and the dinitro compound nitrate (IX) in the second. In the nitration ofα-ethylveratryl alcohol (II) with 6–12 molecular proportions of HNO3 the same, nitro compounds were obtained as in the nitration of (VI). 4. It may be supposed that a) the formation of nitric ester groupings in nitrolignin is due to the esterification of benzyl alcohol hydroxyls and the replacement of benzyl ether groupings by ester groupings, and b) the nitration of lignin with a considerable excess of nitric acid is accompanied by degradation with replacement of side chains containing benzyl alcohol or benzyl ether groupings by nitro groups.