نتایج جستجو برای: tetra methyl ammonium hydroxide
تعداد نتایج: 156089 فیلتر نتایج به سال:
The anion of the title salt, (C(10)H(10)NO)[ZnBr(2)(C(10)H(8)NO)]·CH(3)OH, has its metal atom N,O-chelated by the deprotonated 2-methyl-8-hy-droxy-quinoline ligand. The hy-droxy unit of the cation is a hydrogen-bond donor to the alkoxide O atom of the tetra-hedrally coordinated anion, whereas the ammonium cation is a hydrogen-bond donor to the methano-lic O atom. In the crystal, adjacent ion pa...
In the title compound, CH(3)NH(3) (+)·BF(4) (-)·C(12)H(24)O(6), the methyl-ammonium cation makes three N-H⋯O hydrogen bonds to the 18-crown-6 mol-ecule. The -NH(3) (+) and -CH(3) groups of the cation adopt a staggered conformation. The F atoms of the tetra-fluoridoborate anion are disordered over two sets of sites in a 0.519 (11):0.481 (11) ratio. Weak C-H⋯F inter-actions occur in the crystal, ...
In the crystal structure of the title salt, C16H36N(+)·CH3BN(-), the tetra-n-butyl-ammonium cations and [BH3(CN)](-) anions are connected via weak C-H⋯N inter-actions, forming chains along the b-axis direction. The anion is almost linear with an N-C-B angle of 178.7 (2)°. The C-N-C angle values at the core of the tetra-n-butyl-ammonium cation range from 105.74 (11) to 111.35 (11)° with an avera...
Using chiral quaternary ammonium hydroxide as base, cycloetherification of linear achiral diarylheptanoid 5, by way of an intramolecular SNAr reaction, provides enantiomerically enriched cyclophane 6 in good to excellent yield.
Currently, the main limitation of Anion Exchange Membrane Fuel Cells is related to their low chemical stability under alkaline conditions due degradation quaternary ammonium-based head groups, which lowers transportation hydroxide ions as well. The knowledge intermolecular interaction various ammonium groups with key improving ion’s diffusivity and groups. Consequently, different anion exchange...
A novel method is presented for transesterification of fatty acid esters in phospholipids and triglycerides to benzyl esters while simultaneously recovering free fatty acids as methyl esters. Transesterification is catalyzed by 0.2 M (m-trifluoromethyl phenyl)trimethyl ammonium hydroxide in methylene chloride, 10% (v/v) benzyl alcohol, and 1% (w/v) potassium tert-butoxide, and is complete in 30...
A gas-liquid chromatographic procedure has been developed to quantitate dipicolinic acid in bacterial spores. The culture, washed from a plate, was hydrolyzed with acid containing the internal standard, pyridine-2,4-dicarboxylate, and then extracted into methyl isobutyl ketone. The internal standard and dipicolinic acid were then extracted into a small volume of trimethylphenylammonium hydroxid...
A novel, conformationally preorganized nonnucleosidic universal solid support for oligonucleotide synthesis was developed. The solid support featured two chemically equivalent hydroxy groups locked in syn-periplanar orientation and orthogonally protected with 4,4'-dimethoxytrityl and acetyl groups. The solid support was extensively tested in the preparation of oligonucleotides and their phospho...
Studies on the synthesis of a hydrothermally prepared 33% porosity xTiO2•(1-x)SiO 2 (x=0.0001-0.04) catalyst with different tetra-N- propylammonium hydroxide/tetraethylorthosilicate molar ratios show that tetra -N-propylammonium ratio = 0.5 provides maximum selectivity butanone-2 formation. The analysis data use synthesized in presence containing xTiO •(1-x)SiO obtained by hydrothermal reaction...
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