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Showing 1 to 20 of 83 for “"dialkyl"”.
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The Vulcanisation of Elastomers with Bis (Dialkyl) Thiophosphoryl Disulphides
Bis(diisopropyl)thiophosphoryl disulphide is used as a sulphur donor vulcanising system for cis-1,4-polyisoprene. It is shown that the network structure consists of polyand disulphidic crosslinks at early stages of cure, simplifying at optimum cure to monosulphidic crosslinks. Pendent accelerator …
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Preparation of N,N'-Dialkyl bis(diamino) diphenylmethanes and N,N'-Dialkyl bis(diamino) benzophenones: preparation of B-hydroxy sulfonamides and B-hydroxy sulfinamides
N,N'-Dimethyldiaminodiphenylmethanes and N,N'-dialkyldiaminobenzophenones were successfully prepared from the respective primary amines via alkylation of their methanesulfonamide derivatives. Initially N,N'-diaminodiphenylmethanes and N,N'-diaminobenzophenones were treated 0 with 2.2 equivalents of …
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Photobenzidine rearrangement: Photodecomposition of N.N'-dimethylhydrazoaromatics and 1,4-dialkyl-1,4-diphenyl-2-tetrazenes
Acid-catalyzed and thermal rearrangements of hydrazoaromatics have been well documented; however, little is known about light-2 induced benzidine rearrangements^ Weiss reported that azobenzene and aniline were formed in the photolysis of an alcoholic solution of hydrazobenzene with a mercury lamp. …
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Ring opening reactions of some dialkyl substituted 1, 3, 2-dioxathiolan-4-one-2-oxides
The synthesis and polymerisation under various conditions of a series of 1,3,2-dioxathiolan-4-one-2-oxides (α-hydroxy carboxylic acid anhydrosulphites) derived from disubstituted α-hydroxy alkanoic acids has been studied. In thermal decomposition reactions the length of the nalkyl group in methyl, …
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Synthesis, characterisation and coordination chemistry of novel N-alkyl- and N,N-dialkyl-N'-acylthioureas
A series of N-alkyl- and N,N-dialkyl-N'-acylthioureas are synthesised and characterised. The crystal structure of N-butyl-N'-benzoylthiourea indicates that an intramolecular hydrogen bond locks the potentially bidentate chelate moiety into a planar six-membered ring with an overall rod-like …
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The synthesis and thermal rearrangement of 2,5-Dialkyl-1,3,4- triphenyl-2,4-cyclopentadien-1-o1's
Three 2, 5-dialkyl-1, 3, 4-triphenyl-2, 4-cyclopentadien-1-ols and 2, 5-di(t-butyl)-1, 3-diphenyl-2, 4-cyclopentadien-1-ol were prepared from their precursor ketones using phenyllithium and Grignard reagent. In general, the phenyllithium reagent produced products faster and in better yield and …
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Study of the reaction of nitriles with dialkyl phosphites for synthesis of a-Amino-bis-phosphonates
<p>Amino bisphosphonate compounds are found in a vast array of products from water chelators to flame retardants to pharmaceuticals. Previous methods to synthesize these compounds involved the use of protic acids, which don’t provide ideal conditions for the starting materials containing acid …
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Synthesis, characterization and potential chromatographic separation of palladium and platinum complexes of N,N-Dialkyl-N'-Benzoylthioureas
A series of para-phenyl substituted N,N-dialkyl-N'-benzoylthioureas where para-phenyl substituents are H, Cl, Br, I, NO₂ and OCH₃ and alkyl chains are -CH₂CH₃, -(CH₂)₃CH₃ and and -CH₂C₆H₅ as well as their corresponding neutral bis complexes of type cis [ML₂] where M = Pd(II) and Pt(II) have been …
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Synthesis characterisation and chemistry of N-alkyl-and N,N-dialkyl-N'-acylthiourea platinum(II) and palladium(II) complexes
N-(n-butyl)-N-methyl-N'-benzoylthiourea and N-(n-butyl)-N-methyl-N'-naphthoylthiourea (HL) have been synthesised and characterised. These ligands react with K2PtCl4 to yield neutral square planar cis- [Pt(L-O,S)2] complexes. These complexes exist as mixture of EE, EZ and ZZ isomers.
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The Reconstruction of Climate in Beringia by analysis of Glycerol Dialkyl Glycerol Tetraether (GDGT) Distributions using High Performance Liquid Chromatography – Mass Spectrometry (HPLC-MS).
… spectrometric detection (HPLC-APCI-MS). Glycerol dialkyl glycerol tetraether (GDGT) ratios within the extracts were used to reconstruct sea surface temperatures (SSTs), mean air temperatures (MATs) and pH. Climatic and environmental parameters were successfully assessed and reconstructed using …
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Investigation of structure and permeability of surfaces modified with self-assembled monolayers
… the behavior of the interface. Two groups of dialkyl sulfides are prepared and studied: a purely hydrocarbon dialkyl sulfide with the structure CH₃(CH₂)₁₇S(CH₂)<sub>n</sub>CH₃, where n=7, 9, and 17, and a carboxylic acid containing dialkyl sulfide with the structure …
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Synthesis of N-alkyl-and N,N-dialkyl-N'-acyl- and N'-aroythioureas, and aspects of their co-ordination chemistry with Pt(II)and Pd(II)
The synthesis of simple, and also bipodal N-substituted N'-acyl- and N'-aroylthiourea ligands has been investigated, along with aspects of their co-ordination chemistry to Pt(II) and Pd(II). The ligands are commonly produced by reacting a secondary or primary amine with an acyl or aroyl …
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Determination of platinum, palladium and rhodium, in aqueous media by means of reversed phase-high performance liquid chromatography (RP-HPLC) after complexation with N,N-dialkyl-N'-acylthioureas
The complexes were successfully separated using conventional Reversed Phase-High Performance Liquid Chromatography (RP-HPLC) and a UV detector. A simple method of complexation of platinum(II) and palladium(II) in acidic, aqueous samples was developed. This method involves the mixing of excess …
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The relationship between urinary organophosphate pesticide residues and reproductive development among boys living in the rural Western Cape
… and oestradiol (E2)) and urinary levels of 3 dialkyl phosphates (organophosphate pesticide metabolites) including di-ethyl, di-methyl and di-methyl triphosphate (DEP, DMP and DMTP). Results: The median (interquartile range) of age and sum dialkyl phosphates of the school boys was 12 years …
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Kinetics and Mechanism of Syn, Alpha' Lithiation of Tertiary Benzamides
The reaction of N,N-dialkyl-2,4,6-triisopropylbenzamides with sec-butyllithium in cyclohexane yields a product in which metalation has occurred exclusively at the carbon adjacent to nitrogen and syn to the carbonyl group. Evidence obtained by nuclear magnetic reso- nance, freezing point depression …
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Synthetic and Mechanistic Investigation of Alpha-Amido Carbanions
… to nitrogen. The syntheses of ten different N,N-dialkyl amide systems are reported, five of which have been successfully substituted via an (alpha)-amido carbanionic intermediate.
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