553-54-8Relevant articles and documents
Palladium-Catalyzed Silylation of Aryl Chlorides with Bulky Dialkoxydisilanes
Fukui, Keitaro,Saito, Hayate,Shimokawa, Jun,Yorimitsu, Hideki
supporting information, p. 1328 - 1332 (2020/08/13)
Arylsilanes bearing a bulky alkoxy group on the silicon were synthesized from aryl chlorides and dialkoxydisilanes under reaction conditions utilizing SingaCycle-A3 as a palladium precatalyst and lithium benzoate in wet DMA. This report proposes the first direct and catalytic method for introducing tert -butoxy- or 1-adamantyloxysilyl groups onto various aryl moieties through the silylation reaction.
New MALDI matrices based on lithium salts for the analysis of hydrocarbons and wax esters
Horká, Petra,Vrkoslav, Vladimír,Hanus, Robert,Pecková, Karolina,Cva?ka, Josef
, p. 628 - 638 (2014/07/22)
Lithium salts of organic aromatic acids (lithium benzoate, lithium salicylate, lithium vanillate, lithium 2,5-dimethoxybenzoate, lithium 2,5-dihydroxyterephthalate, lithium α-cyano-4-hydroxycinnamate and lithium sinapate) were synthesized and tested as potential matrices for the matrix-assisted laser desorption/ionization (MALDI)-mass spectrometry analysis of hydrocarbons and wax esters. The analytes were desorbed using nitrogen laser (337.1 nm) and ionized via the attachment of a lithium cation, yielding [M + Li]+ adducts. The sample preparation and the experimental conditions were optimized for each matrix using stearyl behenate and n-triacontane standards. The performance of the new matrices in terms of signal intensity and reproducibility, the mass range occupied by matrix ions and the laser power threshold were studied and compared with a previously recommended lithium 2,5-dihydroxybenzoate matrix (LiDHB) (Cvac?ka and Svatos?, Rapid Commun. Mass Spectrom. 2003, 17, 2203). Several of the new matrices performed better than LiDHB. Lithium vanillate offered a 2-3 times and 7-9 times higher signal for wax esters and hydrocarbons, respectively. Also, the signal reproducibility improved substantially, making this matrix a suitable candidate for imaging applications. In addition, the diffuse reflectance spectra and solubility of the synthesized compounds were investigated and discussed with respect to the compound's ability to serve as MALDI matrices. The applicability of selected matrices was tested on natural samples of wax esters and hydrocarbons. Copyright 2014 John Wiley & Sons, Ltd. Copyright
Method for producing, via organometallic compounds, organic intermediate products
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Page/Page column 4, (2008/06/13)
The present invention provides a process for preparing aryllithium compounds by reacting haloaliphatics with lithium metal to form a lithium alkyl and reacting the lithium alkyl with aromatic halogen compounds of formula (III) in a halogen-metal exchange reaction to form the corresponding lithium aromatics of formula (IV).
The reaction of n-butyllithium with benzoic acid: Is nucleophilic addition competitive with deprotonation?
Beak, Peter,Pfeifer, Lance A.
, p. 537 - 541 (2007/10/03)
An evaluation of a branching vs sequential mechanism for the reaction of benzoic acid with n-butyllithium favors the latter.
Proton affinities and aggregation states of lithium alkoxides, phenolates, enolates, β-dicarbonyl enolates, carboxylates, and amidates in tetrahydrofuran
Arnett, Edward M.,Moe, Kevin D.
, p. 7288 - 7293 (2007/10/02)
The proton affinities of the title compounds are represented by their heats of deprotonation, ΔHdep, through reactions with lithium bis(trimethylsilyl)amide, LiHMDS, in tetrahydrofuran at 25°C. Aggregation numbers of the parent acid and of its lithium salt at a concentration of 0.10 M were obtained by vapor-pressure osmometry at 37°C. Lithium phenolates were also studied by conductivity at 25°C. ΔHdeps for 27 oxygen, nitrogen, and carbon acids of varied types correlate fairly well (R = 0.95) with their published pKas in dimethyl sulfoxide although their degrees of aggregation in THF vary from one to over seven. In some cases, the ΔHdep of an acid is strongly dependent on the concentration ratio of LiHMDS to that of the acid's lithium salt at the time of measurement. Aggregation numbers determined by VPO in this report agree with available published values obtained by previous workers using several techniques. There is no obvious relationship between the aggregation number of the lithium salt and the basicity of the corresponding anion as represented by ΔHdep. This observation along with independent evidence for equilibria between monomers, dimers, tetramers, etc. for a number of compounds indicate that there are only small differences between the relative stabilities of different aggregation states. Conductance data for lithium p-nitrophenolate were treated by Wooster analysis, the results of which suggest equilibria between ion triplets, ion pairs, and free ions in THF. The conductance of LiHMDS in this solvent is surprisingly high, and this property was used to demonstrate an interaction between LiHMDS and lithium o-tert-butylphenolate.
Glycolate ester peracid precursors
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, (2008/06/13)
The invention provides novel bleaching compositions comprising peracid precursors with the general structure STR1 with R, R', R" and L as defined in the specification. Novel peracids and precursors are also herein disclosed. These peracid precursors provide new, proficient and cost-effective compounds for fabric bleaching.
Reduction of Sulfur Dioxide and Carbon Dioxide with Benzoin Carbanion. Oxygen Transfer from Products Formed by the Reduction of Sulfur Dioxide to 7,7,8,8-Tetracyanoquinodimethane
Akiyama, Fuminori
, p. 3951 - 3956 (2007/10/02)
A reaction of sulfur dioxide (SO2) with benzoin carbanion (the lithium salt of benzoin dianion, 1) in tetrahydrofuran (THF) gave a mixture of benzyl (2) and benzoin (3) in yields of 83 and 17 percent, respectively, irrespective of the reaction temperature between -78 and 25 deg C.The reaction of carbon dioxide (CO2) with 1 in THF gave a mixture of 2 and 3 accompanied by the formation of a small amount of lithium benzoate (4).The proportion of 2 in a mixture of 2 and 3 formed in the reaction of CO2 with 1 were 49, 30, and 20percent at -78, -22, and 25 deg C, respectively.The reaction of SO2 with 1 in the presence of 7,7,8,8-tetracyanoquinodimethane (TCNQ) gave oligomers of TCNQ with a yield of 60percent, in which some parts of the cyano groups were transformed to carboxylato groups.
